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Questions related to Geography
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Climate at polar regions
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Yes, it is true. It is due to obliquity of earth's axis to the earth's orbital plane. As a result, sun appears to describe a sine curve along earth's equator. When sun is in the south of the equator, winter nights are long in the northern hemisphere and days in the southern hemisphere.
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Satellites to measure sea surface wind speed can take different data, But for the monitoring of land surface wind speeds.
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Active Radars are the sensors that can be used for evaluation offshore wind speed .
Altimeters provide the wind speed.
Scatterometers provide wind speed and direction (using the CMOD algorithms)
Synthetic Aperture Radars can provide wind speed if you know the direction (and vice versa). Some solutions based on Fourier transforms or wavelet transform allows to obtain wind speeds and directions
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Hello
I would like to know if any simple bioclimatic index has been proposed (as Humidex or Heat Index for mixing the effect of temperature and humidity) to include the deleterious effect of strong winds when T > 37°C or so. I know that some indices already include the cooling effect of strong winds (as net effective temperature) when T is low but I am rather interested by the warming effect of winds. I add that I am looking for a synthetic index (not as complex as UTCI for example).
Thank you in advance
Vincent
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Dear Vincent Moron
The most simple and enough  accurate Index you need was developped by Baruch Givoni "The Index of Thermal Stress" ITS  # 5.6 and #16.1,c (The building Bioclimatic Chart).
.See in his book "Man Climate and Architecture" Applied Science Publishers - London 1976 Reprinted 1901
Take into account that certainly you must consider that no "acceptable discomfort" will you found under the sun, but in the shade properly dressed. Then the formulation is much simple if direct solar radiation is not considered.
Then you need to evaluate which is the acceptable E/Emax value you need according to the sweat rate Inex of humidity. Certainly no Comfort will be found at 37 degC, But you can define the (also) acceptable low metabolic rate...
If you are interested in the way I use it, please write to my email  
Milo E.  Hoffman <mhoffman@tx.technion.ac.il> you will be welcomed 
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In india interstate migration is there but lack of proper data and methodology. plz guide this issue
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Respected  Shinde
“Migration is a form of geographical mobility or special mobility between one geographical unit and another, generally involving a chanh=ge in residence from place of origin or place of departure to the place of destination or place of arrival”
In my opinion three fold study is important to study any migration (intra an interstate both which can be further divided into rural to rural, rural to urban, urban to urban and urban to rural as per census of India definition)
(1) On the area/region experiencing in migration
(2) On the area experiencing out migration
(3) On the migrants themselves (one will have to deal male and female differently because for former Economic reason and for later marriage is an important factor for migration)
In actual we try to analyze it through statistics which only useful for trend analysis. The census of India provides statistics on this aspect ( interstate) (http://censusindia.gov.in/Census_And_You/migrations.aspx.). the data can be purchased in electronic form from the headquarter:
Office of The Registrar General and Census Commissioner, India, 2/A, Man Singh Road, New Delhi -110011 (INDIA), Tel. Nos: . +91-11-23070629, 23381623,23381917, 23384816, Fax No : +91-11-23383145, E-mailID(s): rgoffice.rgi@nic.in.
Following reports may solve your problem
Regards
Zaheen
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I have converted a landsat tm to polygons using raster to polygon tools of arctoolboxs. But I get some irregular and square polygons. Can I get some square polygons and its size is equal to the pixel of tm imagery? Thank you.
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Hello
ArcGIS can not directly convert raster toVector, the conversion tool is based on pixel values,
you can digitizing your image with editing tools, or binarize the image ( to 0 and 1) with classification, and in this case you made the conversion.
good luck
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I need its exact meaning
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Dear Subir,
Oro- is an element, from the greek, that makes up names with meaning of 'mountain'.
Orotemperate is a thermotype from temperate climates.
Thermotypes clasification are: infra-, thermo-, meso-, supra-, oro-, cryo-,
Have a happy New Year.
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Can any one post table on field capacity/available water holding capacity of different types of soils?
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THANK YOU VERY MUCH SIR FOR YOUR GUIDANCE.COULD YOU SUGGEST SOME LIGHT WEIGHTED REFERENCE ON THIS TOPIC
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I am planning to conduct a study in tropical logged-over forest catchment. What the best method can be used for the measurement?
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Dear Mr. Khalit,
I am not sure what your precise objectives are but obviously am entering a very ambitious project. First and foremost you have to make a careful site selection and try and find a test site to carry out this. I was involved in such a project. You have to be sure that the catchment is an almost-closed system where you can study colluvial, alluvial and fluvial sediment input prior and after have logged the area within the project. Is this what you are aiming at or am I on the wrong scent?
Best regards
Harald G. Dill
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I am working on Pedestrian areas. In fact I want to find parameters that use to investigate feasibility of changing a street to pedestrian area. Parameters should be spatial. 
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Hi,
as a Urban designer, I recommend you browse through these two books, namely te conclusions paragraphs of each chapter, to find best parameters ( you have to decide based on cultural / planning habits of your region of interest):
1 WHYTE, W.: Social life of small urban spaces. Washington: Conservation Foundation.
2 GEHL, J.: Life between buildings: Using public space
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In my PC, when I go to install it, a note is coming "Run time error 339" and "Component THREE32.OCX or one of its dependencies not correctly registered" 
Please provide me usefull techniques to solve this problem.
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Respected Aher Sir, 
I already downloaded from that site but there is problem related to files, which is already stated in my question.
If possible, please send the original version of full software via e-mail, 
Thank you. 
Can anyone suggest remote sensing data for detecting and tracing the accurate path of rivers and stream ?
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I going to write a paper related to precise mapping of stream and rivers from RS data. Also, if anybody is willing to do a contribution as a co-author for the same task, kindly inform me.   
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An alternative approach would be to use LiDAR (or photogrammetry) to build a DEM and then model your river network over the surface. In many environments water in streams is obscured by vegetation and cannot be detected directly by RS. Moreover in arid environments stream courses can be intermittent, so the effectiveness of the optical / radar approaches will depend on capturing data at the right time. We have compared a stream network derived from a DEM modelling approach to a network derived from conventional manual photogrammetric interpretation over the same area and found remarkable agreement in the results (sorry, unpublished). True, the LiDAR DEM approach is a model of the environment, although so too are networks derived from other means. The best approach will depend on the environment, scale and accuracy you are aiming to achieve together with your budget. Hope this helps.
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In a recent paper (>5-6 years ago), I remember seeing a paleogeographic reconstruction of South America (it looked something like the attached link, but for South America) during the period it was isolated from other land masses (either the Eocene, Oligocene, or Miocene). However, when I went to try to find the figure again, I could not locate it. All of the paleogeographic maps of South America I have seen either focus on the northwestern corner of the continent or Patagonia. I was wondering if anyone knew of any papers that had presented similar maps of South America during this time period.
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Most of Christophers Scotese impressive maps and datasets are available for free, check https://www.researchgate.net/profile/Christopher_Scotese3
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Hello every body.
I'm researching about methods for indoor navigation, for example why-finding correct route to exit  by an agent in a building & I need some good references about this topic.
Thank you for your answers. 
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Perhaps read about ikeGPS – point at a wall, and it measures the perimeter, area, etc. 
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I am interested to work on geospatial mining. 
Preferably geographic images.
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When someone working on geomorphology of two rivers in the same watershed wants to know the absolute age of the rivers under study, what exactly is meant by the 'age of river'? Does it mean 'age of its channel' through which the water flows (which obviously varies from head to mouth) or the age of entire valley in which the river channel is situated? or these two are the same? or something else? What are the advanced techniques to determine the age of the earth? For the sake of making the question clear, two .kmz files of two rivers, the Ganga River and the Son River of the same basin (the Ganga Basin) are attached here.
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You can make a good approximation of the absolute age of a "river" by determining the absolute age of the deepest river deposits in the specific basin.
In the case you have two rivers and you want to determine the relative age, you can also use the ages of the deposits. Additionaly you can evaluate the possible lithology of  each river-branch. For example, you will have entirely different lithology of the deposits, if the source rock is different.
I hope I helped you
Regards
Ioannis Alexandridis 
How we can perform the Landslides Zonation Mopping using Remote Sensing Data?
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Is there any advance DEM for modelling of landslide ?
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Hi Sainath, Yes there is. You need SAR platforms for this and perform interferometry of the SAR stereocouples to produce an interferogram. This geodetic method uses two or more synthetic aperture radar (SAR) images to generate maps of surface deformation or digital elevation, using differences in the phase of the waves returning to the satellite or aircraft. The technique can potentially measure centimetre-scale changes in deformation over spans of days to years. It has applications for geophysical monitoring of natural hazards, for example earthquakes, volcanoes and landslides, and in structural engineering, in particular monitoring of subsidence and structural stability. You should preferable do the observations with an airplane acquiring the stereocouple, because you need high spatial resolution as well, at least for local landslides. Cheers, good luck and success, Frank
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I am currently designing an Honours option course entitled Space, Place and Sensory Perception (see brief synopsis below), start date Jan 2015. I’ve spent a good few months amassing references and identifying case studies/practical exercises but I am well aware that there will be things out there that I’ve missed that would perhaps prove to be more useful than that which I have already found.
Does anyone have any suggestions? Eventually I plan to share the course outline with the Sensory Studies network.
The course aims to show how the senses – sight, touch, taste, hearing and smell - play a vital role in shaping the way we interact with, and attune ourselves to, the world around us. It will focus on understanding these everyday sensory worlds and their variation across various historical and geographical contexts. In so doing, it hopes to demonstrate to the students that sensory perception is as much a social, cultural and political practice as it is a physical or biological function working through a range of topics such as silence and noise, darkness and light, pleasure and disgust, immersion and distance,  atmosphere and affect. The course will attempt to be as sensorially engaging as possible in its pedagogy and to this end a series of immersive tutorials will run alongside the lectures providing numerous opportunities for students to physically explore their senses.
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Make sure that your reading list includes at least some of the later works of Reginald Golledge, an Australian behavioral geographer who lost his eyesight (but not his vision, as he liked to remark) at mid-career and wrote extensively on the experience.  Works by Chinese geographer Yi-Fu Tuan may also be useful, particularly Space and Place (1977), Landscapes of Fear (1979), and Escapism (1998).  Good luck with the course--it sounds quite interesting and useful.
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Water sampling method.  
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It is really difficult to provide a simple answer to your question. The answer depends a lot on the goals of your work. We know that water quality in a lake can vary spatially and with depth. If you need to characterize this spatial variation, then you must sample the lake at several locations and at multiple depths. The answer also depends a lot on the size of the lake. Small lakes in the range from a few to maybe 100 ha may only need to be sampled in one or a small number of locations. Available funds for water quality characterization will play an important role as well. Here in New York State in the US, we have a lake water quality characterization program in which samples are collected monthly at two depths---one meter below the surface, and from just below the top of the hypolimnion. Samples are always collected in the same location within the lake so that water quality trends over time can be detected. If your lakes show seasonal stratification, then water quality above and below the thermocline can be quite different. At a minimum, seasonal changes are usually tracked, which means at least four times per year in a northern temperate climate. Seasonality may be quite different in your location in India. I hope this information helps, and good look with your work.
Mapping waste indicators: have you examined papers which reveal spatial patterns of waste indicators in your country/region?
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Few environmental reports provide a spatial analysis of waste indicators through various scales within a country (rural locality- city-county-development region-country) and such studies are not quite widespread in literature . https://www.researchgate.net/publication/261296953_Geography_of_waste_as_a_new_approach_in_waste_management_study?ev=prf_pub Do you think that environmental authorities should be obliged to provide maps concerning municipal waste indicators for all administrative territorial units in a country? What implications would have a such initiative?
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I have some experience with waste management.  Fascinating idea, mapping wastes.  Would be very useful and interesting.  Seems like it would raise numerous questions we may not be prepared to answer.  Which wastes are going where?  Why?  For how long?  Consequences?  How do and how should distribution and management of different waste streams (industrial, municipal, household, agricultural,...) differ?  In the US most waste management regulation and monitoring is done at the state level.  One would think the available data could be assembled to generate maps.  I have seen some reports for specific kinds of wastes (e.g., coal ash) prepared by organizations and activists with specific interests, but I have not seen a compilation for multiple kinds of wastes.  Also, experience shows there is considerable illegal, illicit, reckless, or clandestine waste disposal that is unknown to the state authorities until discovered by accident, and often, even when discovered, it is not reported to regulators.  Mapping unknown wastes disposal practices and sites could only be extrapolated from the number and types of illicit sites discovered, which I think has been done to a limited extent by some US states.  I think I recall some presentations by state waste regulators on numbers and locations of illicit waste dumps, and they have data for permitted waste disposal facilities.  Perhaps you would want to contact some state waste agencies in US.  Unfortunately, government budget cuts in environmental agencies in US have constrained ability of those agencies to collect, track and provide such information in recent years.  Nevertheless, it would seem a place to start.  
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It seems that there are few papers recently using this concept, I wonder why.
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The term "Socialbrache" has been introduced in the 1970s both by social and landscape geographers to explain the then happening change in rural areas: More and more agricultural land was abandonned or signficantly underused. It turned out that the main motives for these changes were changes in the occupation of the villagers: Were they formerly full-time or part-time farmers their attitude towards agriculture changed with increasing occupation outside agriculture (e.g. in manufacturing). As a result, more and more land was not used properly.
In most west European countries this process has ended for several reasons: Existing farmers seek land, environmental protection schemes incl. subsidies allow for underusing, and part-time farming is established.
However, I have no idea about the East European countries: I can imagine that migration to cities, search for occupation outside the primary sector, and the reduced necessity to produce food for subsistence introduced these processes.
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I'm teaching a class to a group of mostly ecologists on climate change X ecology and I want to cover some data sources they might use. I've found good sources on gridded data, GCMs, RCMs, but not yet a nice resource introducing various networks of weather station data and considerations such as biases, inhomogeneities, etc...  I'm not concerned whether the resource is peer reviewed, book, or web, as long as it is good.  Thanks!
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Again, I think Karl provides good overviews of the potential biases in these kinds of data sets.
For SNOTEL use this the attached file
How can we determine the impact of tourism on a waste management system from a city or rural region?
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Tourism may be a significant factor in local waste management plans in case of touristic regions across the world. What methods and tools should be applied in order to outline these complex implications? Please share your thoughts, papers, reports etc.
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Greetings, although the following paper is not fully related to waste management per se, it proposes a risk-assessment based model to manage sustainable tourism development with a focus on water-based resources and their quality. An empirical study with impact measures was conducted.
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I came across the Geodesign framework by Carl Steinitz
Steinitz, C. (2012). A Framework for Geodesign: Changing Geography by Design (p. 224). ESRI Press.
and was wondering if there are examples where this framework was applied on the regional scale.
Looking forward to hear your opinion and examples.
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Hello Alexander Please go through these points may helpful to you,
GeoDesign involves three activity spaces: the work environment (where designers do their work), the design tools (the tools designers use to do their work), and supportive workflows (how designers do their work). Having one of these out of sync can impede the design process.
Work Environment—Today's work environment used by geo-based design professionals involves the field, the desktop, connection to enterprise servers and databases, the use of document management systems, collaborative environments (both inside and outside the enterprise), and interaction with outside agencies and organizations.
Design Tools—Geo-based designers use a variety of tools to assist them as they create their designs. Probably the most frequently used tool, or type of tool, is the drawing tool. The particular type of drawing tool depends on the designer's domain and whether the designer is working in 2D or 3D space.
Supportive Workflows—Most geo-based workflows, at least at a detailed level, are domain specific. Three workflows pertaining to the use of geographic information stand out, however, as being predominantly genetic: one related to land-use change; one related to the design, construction, and management of built facilities; and one related to the use of 2D CAD.
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Copyright issues are a secondary concern as their principal application will fall under the terms of 'fair use'
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GMT - Generic Mapping Tools is an open source program that can be used for generating simple (and more complex) maps and also includes/provides links to databases for various kinds of geographic objects (rivers, boundaries, lakes, roads, cities, relief etc.).
Has often been used in Wikipedia and for some languages there is a special GMT map-making tutorial, see e.g. http://de.wikipedia.org/wiki/Wikipedia:Kartenwerkstatt/Hilfe/GMT. Or see here for the original tutorial: http://www.soest.hawaii.edu/gmt/gmt/pdf/GMT_Tutorial.pdf .
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In South Africa an 'semi-independent' board is legislated to determine municipal boundaries. A set criteria or factors are legislated to be considered. With no weighting applied to these. Is it the same in other countries and what factors do other countries consider?
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You may find it interesting to read the research by Bruno S. Frey on Functional Overlapping Competing Jurisdictions (FOCJ). He makes the case that municipal and regional boundaries should be based on functional criteria (e.g. where do people go for specialized medical treatment or to the opera) versus traditional geographic boundaries that often ignore these functional preferences.
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Theories of Practice: Shove "vs" Schatzki.
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This is difficult to answer because Elizabeth Shove did not purposefully develop a theory of practice. In fact, her work strongly builds on the theoretical framework that Schatzki developed. Shove, however, clearly strives to make practice theory easier to communicate, which resulted in a different treatment of materiality and the elements of practices. Whereas Schatzki talks of the linkages of practices - understanding, rules, teleoaffectivity - Shove conceives them as elements, namely meaning, competences, and material. Material is here treated as an element to simplify matters. In contrast Schatzki talks of material arrangements which are in mutually constitutive relationship with social practices.
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I am writing to overcome a problem that I am facing while using data. I am willing to use the optimal fingerprinting method and the problem pops up when I want to use the downscaled historical data of CORDEX as I want to use the historical simulations of CMIP5 including ALL, NAT and GHG forcing but as I have noticed the only forcing of historical that has been downscaled is ALL . Would you mind telling me if other forcings of historical (NAT, GHG) and control run data are to be used as they are (not downscaled), and if I can simultaneously use downscaled historical ALL (CORDEX) with historical (NAT, GHG) of CMIP5 which have not been downscaled? If the case is that these should all be downscaled to be used, would you please lead me to the right track of how to downscale them to be used with historical ALL (CORDEX).
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Hi Tofigh,  I am not an expert in this process, but doing spatial analysis all comes down to similar problems-missing data. Would using the average of both controls work?
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Greetings, I'm curious that can anyone help me getting an idea for model selection?
I was preparing data with BASINS 4 & Arcgis to use the SWAT model in non-US region. However, I found out that soil data that I can afford is poor with it's quality and doesn't fulfill the basic requirements of SWAT. Most of the soil properties have to be filled with prediction refer to document, "Estimating generalized soil-water characteristics from texture"(Saxton et al, 1986). I know it's a good reference, but what I have to deal with is the soil on the opposite side of globe. I don't feel right using the predicted value which can be assured by no one. This kinda bothers me becuz as I understand, SWAT is quite much dedicated with soil property.(However some say it is just an minor uncertainty and tolerable, but it's not convincing to me....)
This led me to consider adopting HSPF, which is regarded to be lumped model relative to SWAT. According to papers that I read, I could have conclude that outcome of HSPF is trustworthy as long as it's calibrated, even if it's inherent with lump concepts(Brannan et al, 2004; Saleh & Du, 2004; Singh et al, 2005; Xie & Lian,2013;).
I know both models are widely used and proved, but I can't make decision since I'm not so much proficient with models. I'm just a model user, not a modeler yet.
Which would you recommend from below two choices?
1. Choose HSPF since there's no major defect issue with input data.
2. Choose SWAT despite of imprecise input data(soil property) since the structure and concept of model is more "physical based" and well distributed.
Thank you in advance.
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@Dr. Randhir/ Hi, Dr. Randhir.
Soil data which I have can fulfill the parameters required by HSPF with very little supplements, but it's not even close to fullfill SWAT's. It troubles me because I already have once evaluated that SWAT might be more appropriate as the watershed has rural landscape.
Maybe I should check out with FAO database and find out if there were some individual field study has been done. If it doesn't work, I might just pick HSPF and put effort optimizing Ftable with HEC-RAS since there are many small hydraulic structure in stream channel.
Thanks for your advice, have a nice day!
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Geophysical scientists, GIS scientists and geography Scientists. 
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Yes. Contact me at 9915144244 or ubsday@gmail.com
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Greetings, International Development Advisor, currently in the field.  So, this issue is a bit pressing as I am providing support for Primary Health Care clinics.  A simple Python script works in the ArcMAP Python Window, but not in the Field Calculator.  I have attached a screen capture.  I'm trying SQL layer definitions as a workaround.  Thanks!  
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I think the problem is with the encoding of strings.
You seem to get this error when you use %loadpy bar.py:
and bar.py has at the top of the file:
# coding: utf-8
or
# -*- coding: utf-8 -*-
I assume your python interpreter is doing  %loadpy bar.py somewhere
possible fixes:
1) Change/update you python interpreter! As this issue seems to have been fixed (see links above)
2) Try writing your function as a python file, foo.py. Then running from the terminal "python foo.py"  to see if you get the same error! I suspect that might work.
3) Remove the # -*- coding: utf-8 -*- from the top of appropriate files.
Cheers,
Jack
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In his 1970 article "Social processes and spatial form: An analysis of the conceptual problems of urban planning", (from book: Social Justice and the City) David Harvey discusses the two lens (sociology and geography) for analyzing city problems, arguing that the gap has not been bridged between them. Essentially, accusing urban analyses to resort either to "space-less social science" or "space-centered geography". 
Is this still true? If not, what leading frameworks can I seek to explore the bridging of this gap between the said theoretical perspectives of the urban?
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Beginning in the 1990s, the social sciences experienced a so called spatial turn (influenced by the French theory like from Foucault or Lefebvre). Also critical geographers tried to bridge the gap you mention… You can try with David Harvey itself (2008: The Right to the City); Don Mitchell (2003: The Right to the City: Social Justice and the Fight for Public Space), or Clive Barnett (2014: What Do Cities Have to Do with Democracy?), among others…
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Hi all, I have multiple images of different Min, Max, mean and standard deviation values. As parametric classifiers do not take images of different ranges, how do I get make these images equivalent and prepare them for classification? Thanks!
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Hi 
(X - min(X)) / (max(X) - min(X))
X = image 
This is the simplest form of data normalization.
Good Luck!
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My name is Sydwell, I am doing second level in Geography, I urge anyone with information to assist me. THANK YOU.
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William is right. I would also mention the opportunities to analyze spatial data and get some indicators that could help you to make some important decisions related to location. Some examples might be the Nearest Neighbor index, or the Local Moran's index.   
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I am PhD student at University of Pretoria. Could you please assist me with tutorials for analyzing LULC changes for my study area using ArcGIS?  I do not have basic knowledge for GIS and Remote Sensing. Please email the tutorials to maggiemunthali2004@yahoo.com
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Dear fellows,
    I will to compute land surface temperature(LST) from landsat etm imagery. Can the Landsat 7 ETM+ SLC-off data be used to compute land surface temperature because  these products have data gaps ? thanks
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Dear Xuegang Chen
you can also use Modis MOD 11 product :  MOD11C2 or  MOD11C3 for Land Surface Temperature 
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Would this device "Spectrum Techniques Universal Computer Spectrometer UCS30" be able to tell me how many becquerels per kilogram of say sea water or honey? Or is that something that could only be "assumed" be calculation with this device?
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Jason,
A spectrometer describes the wavelengths present in a source - in a manner analogous to a prism expanding a source of light into its component colours. And note, the UCS30 is just the pulse amplifier and shaper - it does not include the scintillator head - which is rather critical.
(it would be like buying a camera, but without lenses)
If you want to measure the level of radioactivity in a material, you will need a calibrated Geiger counter, not a spectrometer.
(generally, the resolution refers to the device's ability to discriminate between wavelengths/energies of a photon. So for any combined detector and amplifier there is a lower bound for the difference in energies that it can tell apart - the better the system, the more finely it can discriminate between two energy sources)
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The White Paper on Transport (2011) has set as an objective to reach buy 2030 an essentially CO2 free urban freight distribution in major cities. What are in your opinion the most promising research alleys one should focus on to reach asuch an objective? Should we concentrate on technologY? Regulation? Stakeholder involvement? Innovative policy formulations? And who should we involve in the research? Why?
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Environmental issues are complex problems, which necessarily means a multi-factorial approach. We need work with scientists as well as with decision-makers, with stakeholders as well as with the civil society - all at once.
We cannot -and should not- maximise or think in terms of priorities or second best, f.i., here. We need work with all the factors altogether. This is what the complexity of the issue involves.
The trouble, though, is that we were never before prepared to think and work in such terms at a global and local level at the same time. This poses a magnificent challenge to humanity as a while. What this means is that we need absolutely change our mindset. Otherwise, we may fail... and collapse.
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So far definitions of fractals are mainly from mathematical point of view for the purpose of generating fractal sets or patterns, either strictly or statistically; see illustrations below (Figure 1 for strict fractals, while Figure 2 for statistical fractals; Fig. 4 for fractals emerged from big data):
Big data are likely to show fractal because of the underlying heterogeneity and diversity. I re-defined fractal as a set or pattern in which the scaling pattern of far more small things than large ones recurs multiple times, at least twice with ht-index being 3. I show below how geographic forms or patterns generated from twitter geolocation data bear the same scaling property as the generative fractal snowflake.
Jiang B. and Yin J. (2014), Ht-index for quantifying the fractal or scaling structure of geographic features, Annals of the Association of American Geographers, 104(3), 530–541, Preprint:
Jiang B. (2015), Head/tail breaks for visualization of city structure and dynamics, Cities, 43, 69-77, Preprint:
The new definition of fractals enables us to see the fractals emerged from big data. The answer to the question seems obvious. Yes, we need the new definition. BUT, some of my colleagues argued that the newly defined fractals are not fractal anymore, because they do not follow power laws.
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Dear Oscar Sotolongo-Grau, Many thanks for your comments!
You are right that Benoit Mandelbrot defined fractal based on fractal dimension or power laws. This definition is too strict for big data. Following this definition, a set of data values that do not follow a power law but a lognormal distribution is not fractal. However, this set is fractal according to the new definition, since there are far more small values than large ones.
Mandelbrot himself said that “For me, the most important instrument... is the eye. It sees similarities before a formula has been created to identify them.” I believe that the new definition captures fairly well human intuitions on fractal or scaling patterns.
Mandelbrot shifted his thinking from strict fractals such as Cantor set and Koch curve to statistical fractals such as coastlines. To some extent, I further relaxed his definition (on power laws) towards heavy tailed distributions in general. 
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I would like to know more about examples of integration of geospatial technologies into the geography curriculum. Would you offer some insights concerning best topics, skills, activities, etc.? What are the challenges facing the use of geospatial technologies in geography classes and how to overcome them?Other useful insights 
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Dear Mohammed,
starting with the new curricula 2016 in Baden-Württemberg (one of the 16 countries in the federal state of Germany, each has its one curricula), spatial technologies are a own topic and are no more integrated as methods in several topics.
Here is an example: In the 2004 curricula, there were for each class several subject specific methods announced, that should be taught. In class 7 & 8 students should use GIS and analyse satellite images, but there are also seven other methods students should use. It is the same in class 9 & 10, GIS is just one of seven subject specific methods. After the subject specific methods have been named, the subject specific topics are listed, e. g. atmospheric processes, dynamic lithosphere, worldwide mobility …)
In the new curricula upvalues digital geomedia. In class 7 & 8, digital geomedia is a own standard (orientation with digital geomedia) just like “global weather- und climate processes” or “phenomena’s of global urbanization”. However, you could argue, that GPS could also be understood and used by students in grade 5 & 6.
If and how spatial technologies are used in lessons depends very much on the teacher. If he/she knows how to handle satellite images and do analyses with infrared photography and how to use GIS and the school has the necessary equipment, then spatial technologies are part of the geography lessons. But in most schools there are one or more PC-rooms that are shared by all classes, so you have to reserve the PC-room each week and most teachers never learned how to do satellite image analyses or use a GIS. Mostly, webGIS are used to gather information, but this could also be done with maps, you do not need a webGIS. Tools like buffer or heatmaps are seldom used.
Lately, there have been a lot of PhD-Thesis on this topic referring to the situation Germany. So I think you should find articles in international journals.
I hope I could help you. All the best,
Thomas
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I am trying to delineate agriculture tile drainage in Midwest. I wonder if anyone has come across with GIS and sub-surface remote sensing techniques to detect tiles/objects buried in shallow depth of soil. Does anyone have any suggestions as to what type of remote sensing can be used to detect subsurface features? I can think of GPR (ground penetrating radar). Any other suggestions would be appreciated.
Thanks in advance !
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You might look at our use of UAV-based thermal imaging described in the following article: 
How is the human-environment-system “oasis” taught in your culture or country?
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The human-environment-system “oasis“ is a classical topic in geography lessons at university and at school. However there seem to be differences in the way this topic is taught: <ul><li>The hydrological basics of different forms of oases, man-made oases, alterations in the land-use in oases in the last decades, the “classical” oasis …</li> <li>with the use of satellite-images, models, drawings of representative cross sections, pictures, travel reports, statistics, maps, …</li> </ul><p><br />What are the indispensable elements? <br />Maybe you also can compare today’s situation with former times?</p> <p>Thank you very much, kind redards.</p>
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Dear Thomas, I agree with Volker that your topic is "the typical phenomena of an oasis when teaching themes in geographical education." My starting point is "Why fertile soil (oasis) is in the middle of desert?". And the second one "Why do people live in a desert?" I think the open topic is biomes and the climate in the Earth. I used climate graphs and schemas of tree vegetation in the parallel zones of Berlin's Technical University. Pupils could find deserts and strange little area (oases) in the middle of the areas. And the next question "What is a source of water?" Yes, an artesian basin/water. I explained my pupils why water of artesian bores goes up, close to the surface of desert. In an oasis everything revolves around the water. Is it reasonable to use irrigation in the place? Pupils should realise that evaporation is very high and danger for soil (minerals leave in the soil, salinization). The people in oases make barters among the places and it is important to cross over the desert. The people use camels which are adapted to the extreme dry climate. They move between oases and the edges of deserts. Another questions: Which food staff did the people produce in the oasis? And next questions How to navigate cross the desert? How to survive in the desert, out of oasis?  I must say I represent the view of Central European individual about Africa ;-)  Best regards, Jaroslav
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H2O is subtracted from the rest of major element oxides in weathering potential index (Richei, 1943) . What is the reason for that? Is it due to sharp increase of combined water with progressive weathering?
On the other hand, water is not substracted in the Miura Index (Miura 1973) 
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H2O is very mobile during weathering, it not only is a chemical component of rock, but an important media that causes the weathering, it can be imput into the weathering system through fall, like CO2, but unlike the other oxides (e.g., SiO2).
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I would like to know what good x-y coordinate system would translate to a given longitude-latitude from the perspective of earth's axis.
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I'm afraid it isn't as simple as the Pythagorean formula that some suggest above, because the distance has to be determined over a 3D Earth. Also, latitude and longitude aren't distance units, but angles.
I haven't checked the formulas, but I believe P. Ciren above has it right. I think the equations given are for a spherical model of the Earth - please correct me if I'm wrong.
I know that the equations would differ depending on whether you're using a spherical or ellipsoidal model for the Earth. If you need extreme accuracy, you probably want to use the ellipsoidal equations. Latitude points taken from the GPS system are "geodetic", not "geocentric" (see https://en.wikipedia.org/wiki/Latitude#Geodetic_and_geocentric_latitudes), and they refer to the WGS84 datum, which uses an ellipsoid rather than a sphere to model the Earth.
For most day-to-day applications, the difference in values you'd get using the spherical vs. ellipsoidal calculations are negligible. But, I thought I'd mention it since it wasn't yet mentioned in the answers :)
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I can create a line feature class of contours from a raster surface in ArcMap but I do not know how to create a 3D surface layer.
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Dear all
My question looks simple. What is the exact  meaning  of DEM resolution and relationship between it and the real pixel size of a map and topographic map scale?
For example when a DEM is derived from a contour layer with 10 m intervals so what is that resolution?
Totally, are there any relation? 
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The resolution of a DEM commonly refers to its horizontal (x-y) resolution, meaning a 25m-resolution DEM has a real pixel size of 25x25m, where one elevation value is assigned to each pixel. There is no direct relation to the contour intervals used to derive the DEM (that would refer to the DEM's vertical resolution, which is rarely provided).
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Contour lines are an important for studying locations of see level in Pleistocene, where these locations changed several times.
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thanks Mr Hyder, I,ll try to do>
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A) Inspiration:
1."Does causality involve contiguity"-from Mario Bunge in his book: "Causality and Modern Science"
2. Torsten Hägerstrand and his Time Geography
B) Context: urban sprawl/spatial multipliers
C) Main assumption: the central business district is known and is stable in time and geographic space
D) Question breakdown: Can the trajectory of urban growth be determined (e.g. centrifugal forces radiating from the CBD) if patterns of spatial contiguity are identifiable?
E) Empirical source: spatial contiguity is analyzed through images of the land mass (e.g. remotely-accessed).
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It's important to note that the "third revised edition" of Mario Bunge's book was published in 1979, and is simply a slightly revised version of the second (1963) edition. The philosophy of causation has come a long way since then; two major works are Wesley Salmon, Causality and explanation. New York, NY: Oxford University Press (1998), and Nancy Cartwright, Hunting causes and using them. Cambridge, UK: Cambridge University Press (2007). See the attached paper for a more extensive bibliography and a discussion of the methods that can be used to demonstrate causation.
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Can anyone please help me. I don't know what the Problem is: I downloaded Sentinel 1 data (Level 1 S SLC) and opened them in the sentinel 1 toolbox. But when I add them in the window for the InSAR coregistration, I don't have any layers to select for the master image and the toolbox always reports the problem: "Operator 'CreateInSARStackOp': Value for 'Slave Bands' is invalid". What is the Problem? Do I have to preprocess the SLC's?
I allready debursted them, but that also doesn't help.
Thank you for your advices!
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I had the same problem with Sentinel 1 Toolbox. You can use NEST, it does not have this problem.
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Looking for co-authors interested in using the various ranking systems (Gravelius, Horton, Strahler, Botanical, Horsfield, Tokunaga, etc.) applicable rivers catchement (Case study Jijila river, Dogrogea, Romania). Article highlights the disadvantages and advantages of each model. I want to implement a model (with application in geography, biology, neurology) to comprise aspects of the existing ranking models. I'm open to ideas from all those interested.
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I'm interested.
I did some work on this and I can share sources and results.
Thanks
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 I am working on land cover raster. I want to calculate predominant land type category (majority) for each county. How to execute this?
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Except for the zonal statistic you can split the raster data into smaller raster data by county map. Then check the attribute table.
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With neoliberal policies can there be affordable housing for the poor?
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In india, the affordability of housing for the poor is still a question which cannot be answered, but to a certain extent the housing scenario is being influenced by neoliberal policies
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I am really new in this field and would require some help from you guys.
Anybody willing to throw some light? It doesn't matter which software to use. I want to have a quick start and build my confidence in it first.
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You might use glm with family=binomial using as covariates the proportions of the neighbours, which you could extract from you shp file (if your spatial objects are poliginals) using the function poly2nb.
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I'm doing my thesis about biogeography as a discipline of geography.
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Dear Ivan. I used to study at the Department of Biogeography, Faculty of Geography, Moscow State University. If you are interested I could provide direct contacts of English-speaking staff members of this department who might help you with your request better than anyone. Regards, Andrey.
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Since 2011, the waters of Lake Baringo have been rising. Many buildings are destroyed and tens of thousands of people have been displaced. There is no convincing explanation for this phenomenon, but a number of possibilities: tectonic movement, deforestation + heavy rains & run-off, previous siltation of the lakes due to deforestation ... Does anyone know who might be interested in researching this? The RAE Trust (raetrust.org) has 30 years of data that might be useful.
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@ Justin Roborg-Söndergaard: We have just recently carried out a qualitative study focusing on small-scale farmers who have their livelihood bases in the riparian land around Lake Naivasha. We currently compare and analyse data from 2011-2014 and hope to be able to contribute to the topic soon. 
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Do you consider geopolitics as a part or related field of political geography, or perhaps a doctrine instead of scientific discipline?
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Since the days of Ratzel political geography is about the study of state. It varied from study of state as an organism to state as an area, to study of spatial political phenomena. Things changed when Peter J Taylor came who under the "world systems theory" changed the nature of political geography completely. Now state is viewed as an ideology and global economy as the reality (prior to Taylor, state acted as the ultimate reality in political geography). Although under globalisation, state is not same but analysis of political and economic phenomena (say impacts of neo-liberalism) is very much studied at the unit of state.
Geopolitics, on the other hand, as it came into existence in Germany was the study of space from the perspective of state. "Space" was focus. Now things have changed and we are talking about "critical geopolitics".
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We are working with Gobhola cave in Swaziland, which might be the longest granite cave in the world. We know that the granite landscape in the area might be very old. Does anyone know anything about the geomorphological history of the granite landscape round Mbabane in NW Swaziland?
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I am going to introduce you to the most " UNLOVED " Theory in Geology,
and Geo-Physics. It is a combined theory of growth and expansion of
planets.
In one of the prior answers above it stated the age of the granite as being
3029 E 6 years which is roughly 2/3 of the total age of approximately
4544.4 million years. So this begs the questions, why was it buried
deeply under the later accumulated sediments for so long ? Why is it
"suddenly" now exposed at the surface? What happened to all of that sediment?
Where do you put thousands to millions of cubic kilometers of materials
that had to be removed without it just simply coming back and
recovering the granite?
In short, what changed in the evolution of the surface features of Planet
Earth that allowed granite to become exposed in numerous locations
on all the continents, when it is so old, and it was buried for such a long time
protecting it from erosion ?
The answer comes in the limited age of the ocean floors. The oldest
sections of the ocean floors are between 180 million, and 230 million years
old while the oldest pieces of continents can be in excess of 4,000 million
years old. So, why are the ocean floors so young, and why are small
pieces of the continents so very old, and yet they are " just now "
being exposed to the erosion associated with all surface features ?
For roughly 4300 million years the planet gained mass, and materials from
space which successively buried prior layers deeper and deeper, but
about 200 million years ago things inside the Earth began to really heat
up, and materials inside the Earth began, or accelerated their lateral
and vertical movements resulting is segregation, and stratification
where the lighter materials migrate toward the surface, and expand,
while the denser materials move toward the core, and compress.
Since the Earth is made up of 80 % lighter materials, and 20 %
denser materials, there is more growth and expansion internally
than there is compression and densification in the core, so the process
of growth and expansion is gradually accelerating.
The by products of this change in radius and volume is an increase in
the surface area of the planet that allowed the water to pour off the
continents into the newly forming ocean basins. There is a new and
significant difference in elevation between the bottom of the ocean
floors, and the now high and dry continents. There is now some-
where to put all of the thousands to millions of cubic kilometers
of materials that are now eroding off the continents, and
creating new layers to cover the basalt ocean floors.
The erosion and removal of the materials off the continents allows
differential vertical movements of continents that were previously
very restricted in their vertical and horizontal motions, including
spreading laterally to increase the continents surface area is
areas too close to spreading ridges ( The Basin and Range of the
western US ) .
In stead of iso-static equilibrium ( Plate Tectonics ), you now have
iso-dynamic quasi-equilibrium ( Growth and Expansion ). The surface
features of the Earth are constantly in motion and seeking to
eliminate the the differences in vertical and horizontal differences
in mass, pressures and internal, and external forces.
The trouble is that everything is in motion and is changing, so the
results we have now are an instantaneous picture of what it is like now.
It was different in the past, and it will be different in the future.
So Geology is a record of the sequences of changes in the surface features
of the earth due to vertical and horizontal changes in elevations and
distances caused by differential growth and expansion of this
particular Rocky planet as it matures and increases in its overall
dimensions.
The very late ( current ) acceleration in the vertical differences in
the planets surface features, has allowed features buried inside
the Earth for over 3,000 to over 4,000 million years to be
exposed at the surface due to the accelerating erosion and
deposition processes, that were not previously possible in the
prior more static conditions.
My personal theory is that Earth has entered into a transitionary
phase of growth and expansion that will change the planet
from a Rocky Planet, toward a Gas Giant planet.
It is in my opinion an answer as to why the Earth has been able
to have surface life in its oceans and on its land for about the
last 630 million years, and still stay within a surface life
sustaining temperature, and atmospheric pressure range
for such an incredibly long time.
The growth and expansion thins the atmosphere, and the oceans,
it also elevates the land , and it helps keep cooling medium like
glaciers, snow fields and ice fields active and in flux as the
rates of the various changes oscillate in speed and intensity.
In short we owe our existence to a growing and expanding planet.
With out it the temperature maximum of 26 C around 95
million years ago would not have been a peak, it would have
been just a point on a temperature chart that might
have rivaled the temperatures on Venus. ( molten Lead )
When you are enjoying you granite, look up, and think about the
5 to 10 km of materials that were removed by erosion just so
you could look at the nice boulders.
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Need to be more involve in my area of interest
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In Entrepreneurship research Australian Centre for Entrepreneurship Research (ACER) conference is prominent. This year conference is suppose to be held in Sydney. Apart from it, BABSON and Academy of Management are really significant. See this link...
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In my previous question I suggested using the Research Gate platform to launch large-scale spatio temporal comparative researches.
The following is the description of one of the problems of pressing importance for humanitarian and educational sectors.
For the last several decades there has been a gradual loss in quality of education on all its levels . We can observe that our universities are progressively turning into entertaining institutions, where students parties, musical and sport activities are valued higher than studying in a library or working on painstaking calculations.
In 1998 Vladimir Arnold (1937 – 2010), one of the greatest mathematicians of our times, in his article “Mathematical Innumeracy Scarier Than Inquisition Fires” (newspaper “Izvestia”, Moscow) stated that the power players didn’t need all the people to be able to think and analyze, only “cogs in machines,” serving their interests and business processes. He also wrote that American students didn’t know how to sum up simple fractions. Most of them sum up numerator and denominators of one simple fraction with the ones of the other, i.e. as they did it, 1/2+ 1/3 according to their understand is equal to 2/5 . Vladimir Arnold pointed out that with this kind of education, students can’t think, prove and reason – they are easy to turn into a crowd, to be easily manipulated by cunning politicians because they don’t usually understand causes and effects of political acts. I would add, for myself, that this process is quite understandable and expected because computers, internet and consumer society lifestyle (with its continuous rush for more and newer commodities we are induced to regard as a healthy behavior) have wiped off young people’s skills in elementary logic and eagerness to study hard. And this is exactly what the consumer economics and its bosses, the owners of international businesses and local magnates, need.
I recall a funny incident that happened in Kharkov (Ukraine). One Biology student was asked what “two squared” was. He answered that it was the number 2 inscribed into a square.
The level and the scale of education and intellectual decline described can be easily measured with the help of the Research Gate platform. It could be appropriate to test students’ logic abilities, instead of guess-the-answer tests which have taken over all the universities within the framework of Bologna Process which victorious march on the territories of former Soviet states. Many people can remember the fact that Soviet education system was one of the best in the world. I have therefore suggested the following tests:
1. In a Nikolai Bogdanov-Belsky (1868-1945) painting “Oral accounting at Rachinsky's People's school”(1895) one could see boys in a village school at a mental arithmetic lesson. Their teacher, Sergei Rachinsky (1833-1902), the school headmaster and also a professor at the Moscow University in the 1860s, offered the children the following exercise to do a mental calculation (http://commons.wikimedia.org/wiki/File:BogdanovBelsky_UstnySchet.jpg?uselang=ru):
(10 х 10 + 11 х 11 + 12 х 12 + 13 х 13 + 14 х 14) / 365 = ?
(there is no provision here on Research Gate to write square of the numbers,thats why I have writen through multiplication of the numbers )
19th century peasant children with basted shoes (“lapti”) were able to solve such task mentally. This year, in September, this very exercise was given to the senior high school pupils and the first year students of a university with major in Physics and Technology in Kyiv (the capital of Ukraine) and no one could solve it.
2. Exercise of a famous mathematician Johann Carl Friedrich Gauss (1777–1855): to calculate mentally the sum of the first one hundred positive integers:
1+2+3+4+…+100 = ?
3. Albrecht Dürer’s (1471-1528) magic square (http://en.wikipedia.org/wiki/Magic_square)
The German Renaissance painter was amazed by the mathematical properties of the magic square, which were described in Europe firstly in Spanish (the 1280s) and Italian (14th century) manuscripts. He used the image of the square as a detail for in his Melancholia I painting , which was drawn in 1514, and included the numbers 15 and 14 in his magic square:
16 3 2 13
5 10 11 8
9 6 7 12
4 15 14 1
Ask your students to find regularities in this magic square. In case this exercise seems hard, you can offer them Lo Shu (2200 BC) square, a simpler variant of magic square of the third order (minimal non-trivial case):
4 9 2
3 5 7
8 1 6
4. Summing up of simple fractions.
According to Vladimir Arnold’s popular articles, in the era of computers and Internet, this test becomes an absolute obstacle for more and more students all over the world. Any exercises of the following type will be appropriate at this part:
3/7 + 7/3 = ? and 5/6 + 7/15=?
I think these four tests will be enough. All of them are for logical skills, unlike the tests created under Bologna Process.
Dear colleagues, professors and teachers,
You can offer these tasks to the students at your colleges and universities and share the results here, at the Research Gate platform, so that we all can see the landscape of the wretchedness and misery resulted from neoliberal economics and globalization.
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I agree that "For the last several decades there has been a gradual loss in quality of education on all its levels". I think that this decadence is a characteristic fruit of the "moral relativism" that dominates without limits in the university and in most of the modern society. The lack of respect for the absolute values, produces in many a lack of interest in any other knowledge quest. Many are living behind "bread and circus" and so are very prone to irresponsible consumism and hedonism. This has been denounced many times by Popes of the twentieth century and by many other brilliant minds (e.g. Solzhenitsyn, Hans Urs von Balthasar, Dietrich von Hildebrand, Jean Daniélou, Warren H. Carroll, Carlos A. Sacheri, Julio Menvielle, Leonardo Castellani, Alfredo Sáenz and Tatiana Goricheva) but the Media ridicule or ignores their advises.
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try Mendeley Desktop at http://www.mendeley.com/features/ : organise documents/ references with plugins to work with MS words and web browsers
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Required for excursion.
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Hi.
I can send you the maps in question via Dropbox to your e-mail, probably this afternoon...
Best regards from the Canaries,
Rubén
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If you are considering the diaspora in relation to the source region, one issue would definitely be the role of remittances in reconfiguring the distribution of wealth. Relevant reference in this respect are Rigg 2006 "Land, farming, livelihoods and poverty" in World Development, or de Haas 2010 "Migrations and Development". I would also add the influence of culture and social practices learned outside, carried back by return migrants, on the source society and environment.
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Most of the literature I have read using gravity modeling or some variation thereof gives little information about how they determined the value of their Beta. I am interested in hearing from those who have insight into how to estimate this value, in cases with and without real data on the travel behavior of clients.
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In our article we made a theoretical model of spatial interactions in my city - Krakow, for cyclists. We used distance decay function counted for Montreal though, but in our research exact numbers didn't play so important role - we knew polish function wouldn't be so different.
However if you want to model flows as precise as you can, you should estimate it empirically. I just want to say, that you should consider that different purposes of travels have different distance decay function (and beta parameter) - e.g. we are tend to go further/longer to work, then to cinema. This is quiet new concept. [you have some examples here:
1) Access to Destinations:
How Close is Close Enough?
Estimating Accurate Distance Decay Functions
for Multiple Modes and Different Purposes
2)Beyond the Quarter Mile: Examining Travel Distances by Walking and
Cycling, Montréal, Canada.
They were fitting distance decay curves to empirical values].
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I am doing my PHD about some active faults in Mongolia by Paleoseismolgy method. The temperature in this country is about -30 to -40°C in winter. We opened a trenches and we saw cryoturbation deformations associated with seismic deformations. I have no experience in this topic and I appreciate your expertise.
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Hello,
In my opinion it looks like moraine deposit and ice wedge.
I couldn't see a tectonic deformation in those photos.
But it's almost pure that a glacier is formed this territory in recent period.
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Supercontinents grouped the crust in a single mass several times in the Earth's history: this allows to suspect that this is a configuration of minimum energy for the Earth. Why thence they do fail to survive and start to break?
Is the additional energy needed to break supercontinents provided by an internal source or it is due to gravitational perturbations?
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A good synopsis on the subject of supercontinent cycles, including mantle processes related to formation and breakup was published by Nance and colleagues (2013), see here:
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E.g. definitions/meanings/perceptions/expectations/etc. from a geographers, ecologists, historians, artists, etc. point of view (patterns and processes, scenery, cutural or political factors, etc.)?
Thanks already in advance!
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A colleague suggested abook collecting many definitions of landscape (by architects, artists, biologists, ecologists, philosophers, geographers, jurists, writers, semiotics experts, sociologists, historians, urban and landscape planners)... unfortunately in Italian language!
Franco Zagari, 2006 - "Questo è paesaggio: 48 definizioni"
Grandi tascabili di architettura - Gruppo Mancosu editore, Roma
ISBN-13: 978-8887017427 (Amazon; http://www.unilibro.it/).
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i want to explore the usefulness of satellite Remote Sensing for monitoring desertification
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There isn't a 250 m thermal product in MODIS; however, there are techniques where you can fuse both MODIS and Landsat products to get better spatial and temporal resolution.
See this article.
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Study area: India Maharashtra, drought prone area in western Maharashtra.
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Rahul,
If you are interested in drought in terms of rainfall deficit use the Standardised Precipitation Index (SPI).
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I'm interesting in know the periods during the Miocene where the Balearic Islands could have been submerged and, the periods (before the Messinian) where the islands could have been connected to the Iberian Peninsula.
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I suggest to contact directly to Tonyo Alcover (jaalcoverimedea.uib-csic.es) the most upstanding palaentologist on the Balearics at present. Cheers,
Javier
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The main problem of Post-Soviet science is connected with its weak "visibility" that leads to its weak global competitiveness. Very weak growth rates of publication activities of the Post-Soviet countries are noted. In these countries, publication activities of scientists in the journals that are included into the Web of Science and SCOPUS databases are by no means stimulated.
On the SCIMAGO platform, by means of the operator «Compare», I generated graphics on dynamics of publications by Russian and Ukrainian scientists in comparison with the total publication activity in Iran and Turkey (graph).
It is well known that Iran and Turkey implemented stimulating measures aimed at supporting the publication activities of their scientists many years ago. About ten years ago in Turkey a reward of $100 to $300 US dollars was offered for one SCI- publication, depending on the impact factor of the journal. In Iran for one such publication, a reward ranging from 300 to 500 Euros is currently offered by the State University. Besides, they have government grants for the support of such publication activities (up to 20,000 Euros for approximately ten publications). This explains the reason why in 2012 Iran bypasses Russia in total publication activities (graph).
I’m interested in the examples of stimulating measures that are being granted by different countries in the form of publication micro-grants. Generalization of these measures would allow to adapt them for the conditions of Post Soviet countries, where in many fields of knowledge their is absence of publication practice of results of researches in internationally recognized journals.
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Publications can only be stimulated by taking all financial care by sponsors or institute/research organization to publish good papers in reputed journals
None should ever be forced to write a paper. If lured with some gains especially financial gains/ promotion quality will be compromised
Best example is Medical Council of India asking 2/4 paper for promoting /exempting 1 year for promoting.
This has seen emergence of Journals that publish paper after payment and with in a day with out even adequate peer reviewing
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An impetuous rush behind the publications according to the phrase “publish or perish ” which is warmed up by money , can lead to a large-scale falsifications of research results, this is observed in China (Jane Qiu. Publish or Perish in China//Nature. – 2010. – Vol. 453, 14 January) (see also discussion: Tek Jung Mahat “ Issue of Plagiarism in scientific writings”). Very often, we observe the exaggerated research fronts which are warmed up by interests of the big capital, inaccessible clusters of high-impact journal in which authors quote each other(see also discussion: Janos Toth “Authors citation cartel ”). At the present time, when the processes of production, analysis and dissemination of scientific knowledge is under the control of neo-liberal forces , we are not capable to control the quality of this knowledge. It seems that the existing paradigm of formal scientific communications which originates from the 17th century exhausted itself. This gave an origin to a new paradigm in scientific communications -«Liquid publications». What is your opinion about the prospects of liquid publications? Will they be supported by the scientific community in the near time?
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Could you perhaps elaborate on "liquid publication" or link to some resources? What I found on the web is rather abstract and describes only the goals. These goals -- faster publication, collaborative research, better credit attribution -- are in my opinion easy to agree to. I'd be interested how these goals should be reached in practice.
It's like saying "everybody should earn more money". The interesting question is how that's to be achieved and what could be the effects, wanted and unwanted.
How can I create random points weighted by population density within a city?
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I want to create random points weighted by population density within a city. However, in ArcGIS when I perform "create random points" the constraining feature class should ONLY be polygon or line. How can I create random points weighted by a population density (raster) layer?
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Here's some R code to achieve what you're after. It reads in an ESRI raster, takes a random sample of n cells weighted by the raster's values, and exports the resulting points and corresponding population densities as an ESRI shapefile. It requires the raster package and its dependencies. You'll also need GDAL installed on your system. I've attached the code as well, in case there are encoding errors with copy/pasting. I've also added detail to the comments here as per @Tyler's request. (It's a shame we can't style these answers for clarity...) First, the code without comments: install.packages('raster') library(raster) r <- raster('path/to/raster') # note forward slashes in path, not backslashes n <- 1000 cells <- sample(x=seq_len(ncell(r)), size=n, prob=values(r)) d <- data.frame(popdens=values(r)[cells]) coords <- xyFromCell(r, cells, spatial=TRUE) # NB: CRS here is WGS84... you can get the appropriate proj4 string from www.spatialreference.org pts <- SpatialPointsDataFrame(coords, d, proj4string=CRS('+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs')) writeOGR(pts, '.', 'randpts', 'ESRI Shapefile') Now, with comments to explain what's going on: install.packages('raster') library(raster) ## Create dummy raster (see commented line below for reading in true data) # This creates a 10000 x 100 matrix of random uniform numbers between 0 and 1000. r <- raster(matrix(runif(1000000, 0, 1000), ncol=100)) # r <- raster('path/to/raster') # note forward slashes in path, not backslashes ## Random sample of n raster cells, weighted by pop density (i.e. weighted by the values of the raster). # Here, we take a sample of size n from the numbers 1 through 1,000,000 (seq_len(ncell(r)) produces a vector of the integers from 1 to the number of cells of r), where the probability weights of each of those numbers is equal to the values of r, i.e. our dummy population density data. n <- 1000 cells <- sample(x=seq_len(ncell(r)), size=n, prob=values(r)) # We then create a data.frame with a single column, popdens, which contains just the pop density for the sampled cells. values(r)[cells] subsets the vector of pop densities, values(r), to just those values that correspond to the sampled cells. d <- data.frame(popdens=values(r)[cells]) ## Extract lat & lon of the chosen cells and return as a SpatialPoints object # The xyFromCell function identifies the cell-center coordinates for given cells (in this case, cells, the cell numbers of the sampled cells) of the raster object (in this case r, our raster of pop densities). Setting spatial=TRUE returns the object as a SpatialPoints object, which facilitates writing out to a shapefile. coords <- xyFromCell(r, cells, spatial=TRUE) ## combine coords with data to create SpatialPointsDataFrame object # NB: CRS here is WGS84... you can get appropriate proj4 string from www.spatialreference.org pts <- SpatialPointsDataFrame(coords, d, proj4string=CRS('+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs')) ## write out to ESRI shapefile # requires gdal installed on system writeOGR(pts, '.', 'testpopdens', 'ESRI Shapefile')
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Mapping is about abstracting and representing spatial objects in a simplified way that we mere mortals can be able to interpret. Cartographers then use cartograms and other tools to create beautiful maps. The quality of such maps could in some ways be used to define the identity of the mapper as would an artistic masterpiece. GIS provides the necessary tools to aid the cartographer in this quest, but as we all know, it provides more than just tools for mapping as it provides ways of interacting with data in wonderful ways. My take is that GIS Mapping as posted is more than a means of creating an identity ... it allows that but much much more.
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Galleria forests are mostly associated along the river shores and are best seen in Amazon basin.
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there are gret diversity of galleria forest in Brazil, not necessarily is need include in tropical rain forest, they can be occur in subtropical forests and another types of vegetation like " savanas formation" in Brazil called Cerrados.
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We are discussing if the growing of urbanized areas can be recovered by natural areas and in what proportion?
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The freely available tools help in downloading the images which are not of high resolution. So the question is "How can we download the 1 m resolution images from Google Earth?
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You can't. First of all GE images are only RGB renderings, so you are not looking to true DNs of the original images. The NIR band also is not available at all, and the original 2m spatial resolution is also a bit reduced. I'm not considering license that also adds a few strong limitiations of use for those images. In brief, they are not usable for remote sensing applications, but are still interesting for object recognition and visual applications at large scale (e.g. pattern recognition and computer vision methods)
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I have a 2D system, you can think of it as a 2D sheet. There is a formation of ridges in this sheet when it is given a constant in-plane pressure. I want to model the ridge dynamics. Is there any model, equation or theory for the ridge formation?
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Maybe you could find some soft from cig,  for the ridge dynamics, a rheologic model is a good try.
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Sometimes, I want to use a map from Google Maps or a similar website, but it may contain many names that I do not need or may not contain some names required. Also, the map size (especially in Google Maps) may be unsuitable. I need a software that helps me draw the map and edit it (add the pace names required along with the suitable size). Many online tools were tried but the result is not that level I desire.
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How can land use change reveal the frequency and magnitude of natural hazards occurrences? I want to find the relation between these two. I need also some methodology to evaluate a possible relationship.
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Morphometric analysis of a drainage basin is very much important for general evaluation of the river system, but with changing time from quantative revolution towards microw level spatial investigation where it play a very general to Neglect able role.
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It depends on the scoop of your study. It is true that, in much of the hydrological works, morphometry is just a background but it is of real importance in geomorpohlogical works.
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The DEM resolution can be medium resolution (20~100m). 
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For India Cartosat DEM is availble in http://bhuvan.nrsc.gov.in/
For Global, GOTOPO 30, GMTED and IFSAR Alaska also available in addition to SRTM and ASTER,  in http://earthexplorer.usgs.gov/
What do you demand of spatial data?
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Besides positional, temporal and thematic accuracy, logical consistency, data formats and actuality, applications often have further demands or requirements on spatial data. As an example: for indoor routing based on a CityGML or IFC dataset you would want a door-object to always connect two room-objects (or a room to the outdoor environment). Another example: for flood simulation objects (like buildings or infrastructure) should not ‘fly’ over ground. Do you have examples from your field of research, where you have to check spatial data (perhaps even laboriously) for such topological demands or other demands beyond what is usually meant by data quality?
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Probably a very accurate geometrically corrected data is useful for census.
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I think there is a need to examine the relationship between agricultural intensification and soil pollution or soil fertility decrease. Focus should also be directed to if land fragmentation contributes to more soil pollution? A hypothesis is that, in order to increase the production, smallholder farmers will input more fertilizer and chemicals on land. This is a very important starting point for recent agricultural policies in China.
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Intensification leads generally to increased risk of soil degradation. Consequently, soil biota, water holding capacity, and ability to keep nutrients decrease, i.e. Soil fertility may decrease.  Use of chemicals and mineral fertilisers and decrease of organic matter input ( or lowering of organic residues by more intensive use of produced biomass) leads to further degradation, especially of soil structure. In order to keep fertility, these processes need to be avoided or mitigated. Important is especially sufficient input of organic matter of appropriate quality. 
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I need some full waveform experimental LIDAR data.
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There is some sample data here http://rapidlasso.com/pulsewaves/
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I want to make geographic transformation of WRF-ARW results to lat-lon projection like with UPP tool of WRF-NMM. I search for linux scripts or tools similar to UPP.
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hi, you can use the open source software GDAL (http://www.gdal.org/)
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I am trying to show change in land cover using landsat mss tm etm+ and high resolution images. I know that it is a must to perform atmospheric correction in multi temporal data to classify and detect change. Is it possible to perform atmospheric correction of landsat tm etm+ and high resolution images. If it is possible, then how?
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I want to calculate the density of different phenomena in landscape (let's say river density or cave density etc.). There is always a question of what radius should be used. Are there any recommendations for that? I was told about one possible solution with a calculation of autocorrelation (http://video.arcgis.com/watch/401/performing-proper-density-analysis). Does anyone have any (other) experiences, solutions?
Thanks for any suggestion!
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Dear Rok,
the determination of a search radius for point, line or kernel density estimation depends always on your research question and the feature distribution. If your example with caves has an archaeological background the walking distance (maximum per day) would be a possibility.
Another possibility would be (as you suggested yourself) to use spatial statistics. This can be for example Incremental Spatial Autocorrelation or you could also use a factor on the standard deviation on the feature distance.
Best regards,
Felix
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My research focuses on the Alexander von Humboldt atlas pittoresque du voyage: "Vues des Cordillères". I am interested in the history and uses of "atlas", and how the concept "atlas" plus "pittoresque" set up a new way of travelling in an artistic manner in the nineteenth-century, encouraging the connection between artists and scientists.
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Thanks!
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I usually digitize maps by creating a shapefile. Now I want to digitize by creating a coverage. I have tried several times but failed. Please help me.
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Olá pessoal. Eu uso um software brasileiro GIS SPRING desenvolvido pelo INPE, Eu não uso do Arc. GIS. Caso seja imagem TM você poderia realizar um classificação automática mais não é o seu caso
Atte
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My institution is considering buying it for our in-house library, but we're hesitant because there are no reviews on Amazon yet. We're particularly interested in how well mathematical and statistical techniques are explained for people outside of math and meteorology (e.g. Geography, sustainability science). I appreciate your comments.
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I deleted my question, such that there is now no interference.
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I am a new learner of remote sensing. I am working with ERDAS Emagine 9.2. I want to know if it is important to make an atmospheric correction of an image before analysis. What procedure should I maintain to perform atmospheric correction? What are the advantages of atmospheric correction? I would like to understand its accuracy.
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Well, thats a big topic. I'll start from the end:
1) You can measure the accuracy only with ground reference measurements at the time when the image was taken. But normally you can expect at least an improvement.
2) With atmospheric correction methods you correct your image from atmospheric disturbances like path radiance, scattering and sky irradiance.
3) If you have only a single image and no multitemporal aquisitions an atmospheric correction is only necessary if the image is very hazy. This is because normally all pixel values are influenced to the same degree and you can achieve good results with all standard classification methods.
4) There are different methods to correct the images. Empirical methods are Dork object substraction (Chavez 1988) or the empirical line method (for this you will need some reference data). More physically based models are so called "radiative transfer models" (Lowtran, modtran). If you are lucky your Erdas license includes also the ATCOR module with which you can apply this models.
Have a look in this paper, it gives a good overview:
SONG, C., WOODCOCK, C. E., SETO, K. C., LENNEY, M. P. & MACOMBER, S. A. (2001): Classification and Change Detection Using Landsat TM Data - When and How to Correct Atmospheric Effects? Remote Sensing of Environment, 75, S. 230-244.
I hope I could answer your question!
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ArcGIS Desktop
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Dear Shunshun,
It is not really hard to learn ArcGIS. It depends on your willing and patience. It does not mean that GIS is complicated, but you can use it in your field of knowledge step by step. The link below includes a 60 days free trial after creating a global ESRI account. Then, you can accomplish the modules and getting started with ArcGIS through the following wensites:
The free trial is here:
Good luck.
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What motivates you to continue with scientific research? Is it money, reputation, competition, your institution rules, your wish to search for facts, that you want to serve the humanity, because it's your job, or for other reasons? For the universities in third world countries how can we motivate scientific research in your opinion?
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As mentioned only motivated persons can produce and published scientific research in the academic environment. It is a hard job to produce regularly novelty, with enough contribution for the scientific community, impact in the society or industry, and present it in a way that is interesting for the other researchers and for the publishers.
In my opinion, who is really motivated by money usually stay far away of the universities as they do not pay (also cannot) the hours of work you need to achieve (and I underline again here) high levels of novelty, contribution significance and interesting work.
The universities give the scientific environment, the scientific nets, the equipments (labs), the assistants, the computers and software, libraries, inside culture and knowledge, and so on. This is very expensive to build and keeping it along generations as well as maintaining a permanent improvement, beside the serious teaching contribution for which is possible to a university to stay alive within reasonable costs.
I know very few about the universities in third world. Anyway, would recommend to check the payments (are they receiving a dignified wage, i.e. a full-time job must allow to keep a family with kids at university) , to check the number of hours of teaching duties (a very good university lesson is also a hard job, which require preparation, adaptation and a lot of energy which must be balanced between research and teaching) , to check the working conditions given at university, check if they have freedom to study the problems they want or they consider the most important (one must believe in the importance of the work being doing), check the mentioned tolerance to failures, and to check for the access given to the international scientific community as well as to the society.
Universities should invest some of their budget in inviting senior recognized scientists to stay for some periods, to evaluate the environment , transmit experience and their way of working in the field. Young talented future candidates will enrich a lot contacting recognized scientists that are interested in working with these junior fellows.
Of course, with globalization many of sharing opportunities are being closed by the extreme competition and commercialization. Many available knowledge where in the past easily passed from university to university, but not nowadays.
Also, removing responsibility of seniors on preparing future generations to replace them as a natural event when they retire is doing damage. Of course, retirement income should also be a dignified.
Finally, this express only an opinion at this moment which can be changed with discussion and reflection, but hope contribute for the discussion in this very complex subject.
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There have been so many kinds of conceptions about ecosystem stability. What’s the representative connotation of the stability of desert ecosystems, and which essential indicators can be used to reflect their stability in general?
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Hi,
This paper by David Tilman mentions some of the indicators. Kindly have a look.
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In Vanuatu a village is usually defined as a group of dwellings who usually do things together, have one village head such as a villa.
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In India, from colonial heritage village is used in two meanings. First is that of the smallest unit for revenue collection in the countryside. It includes both settlement (basti) and land demarcated as belonging to the resident of the settlement. Village also mean a settlement. It is distinguished from urban settlement in terms of economic activity (predominance of primary activities) and population size. It has a village council (gram sabha) and an elected village head (gram pradhan).
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Mapping out of slums in cities.
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The identification of slums requires work in three dimensions i.e. legal, spatial and social. Tax/Revenue department can help to deal with legal dimension; spatial dimension can be dealt with RS/GIS datasets for indentifying infrastructural facilities/ connectivity (here I fully agree with Saif Uddin). To meet with social dimension, local groups/communities may be approached to get their feedback about slums in a certain area/territory. Therefore, identification of slums is not 100% automated process. It requires empirical study as well.
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Does anyone know how to make in GIS software (Quantum GIS or ArcGIS) parallels and meridians appear on the extreme limits of a polygon? <br />
I was on the sidelines latitude and longitude. How to make the GIS program to appear?<br />
I will put a photo so you know what I want to do.
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Hi Ana-Maria:
I think you can use Print Composer tools in QGIS.
look at Extents dialog to configure how to how them. I hope you find it usefull
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An agronomist colleague and I are looking for known sites to test a field reconnaissance methodology for rapid verification, so we are looking for sites for which local "dark earths" have been verified as being anthropogenic in origin.
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Thank you once again, Wenceslau. I sent Dr. Neves a message last night, but these contacts in Rondonia may be better able to help me in the time that I have left here. I did not know about Zimpel before, but will try to contact him here. I had intended to talk to UNIR archaeologists, so this provides a more specific person to contact.
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For some geographical methods, a city center location in the form of coordinates is needed: e.g. when examining an area within a 5km radius around the city center, or when calculating the distance from the city center.
But where is the city center? I have seen multiple studies in Australia use the General Post Office of a city as its center point, while in Japan the city hall or city office seems to be used. In most cases, these are also the coordinates given by Wikipedia on the respective city entry pages.
However, I have not been able to find much information regarding why the General Post Office or city hall is chosen. The Australian Bureau of Statistics responded to this question by stating there are no "official city centres", and they didn't know of any government office that could provide such data.
Is there any research into this topic, or information how this matter is handled in Australia, Japan or other countries? Thanks in advance for your help!
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Näyhä et al. have located city centers by the most populous 1x1 km grid cell.
See Näyhä et. al. (2013). Body mass index and overweight in relation to residence distance and population density: experience from the Northern Finland birth cohort 1966. BMC Public Health 13:938.
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Mountain areas are under increasing pressure to innovate in order to find strategies to emerge out of development standstills, to endogenously increase attractiveness and competitiveness, and to increase resilience in the face of global change.
The issues of the future are rarely considered in research as well as in government discussion on Alpine resources. Debates have usually focused on the past in order to uncover social-ecological processes or histories of Alpine communities. These studies have shown how during the centuries, Alpine people have been able to adapt to changing conditions while maintaining the well-being of the community and managing the landscape in a sustainable way.
Recent fast driving forces are creating new scenarios for living spaces and new values, such as those related to ecosystem services, that have not been investigated previously.
Through the implementation of instruments of policy planning (see i.e. common agricultural policy and rural development plans), paths of innovation both in government and technologies may foster opportunities for futurability of Alpine communities but also counterproductive actions, threatening their identity.
We aim to investigate the most relevant questions that, if answered, would have the greatest impact on resilience and futurability of social-ecological systems of the Alps.
In particular we are interested to learn how it could make relevant a collective management, as many of the Alpine resources are considered by law as commons.
We hope to gather some questions also during two workshops we are organising (one in Trento, 30-31 may 2014 see https://sites.google.com/site/memoriadelleregole/evento-maggio-2014 and the other at ForumAlpinum at Mid September 2014 see http://www.forumalpinum.org/).
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Have a look at our paper on commons in Tyrol, Austria that have managed the transition from peasant farming to tourism well without much help or interference from the outside.
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Working on a project with contour lines and I wonder if there is a ways to calculate the  metric distance between two contour lines. 
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Thank you Nicolas! I'll try that.