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  • Sotirios Thanos added an answer in Real Estate Economics:
    3
    What technique(s) of analysis can best be used to analyse the relationship between listing/asking price and sales price?
    I am particularly interested in knowing the causal relationship; that is, the prediction power of listing/asking price on sales price.
  • Stam Nicolis added an answer in Particle Physics:
    3
    Are there any characteristic energy scale for quarks?

    Pls Answer me.(Particle Physics People)

    Stam Nicolis

    Most of the mass of the quarks comes from their strong interactions, however; and quantum chromodynamics does have a, non-trivial, scale: it's not scale invariant, since the β-function isn't zero. The characteristic scale is known as Λ_QCD and is of the order of 200 MeV: http://www.int.washington.edu/PROGRAMS/12-2c/week1/hasenfratz_03.pdf

  • Azzam K Almosallami added an answer in General Relativity:
    99+
    Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Azzam K Almosallami

    Dear Erkki J. Brändas,

    You said;  Whatever you do, your STR infested analogue of GR will always give you a factor 2 off. Your work to derive GR results by incorrect scalings is wrong.

    Ok! 

    According to my equivalence principle a part of the rest mass of the free fall object changing to photons, these photon give the particle a kinetic energy to move in a velocity equals to relativistic escape velocity locally at any point in space in gravitational field equals to the gravitational potential at that point in space. The relativistic mass always equals to the rest mass, and in this case m0c is constant..no radiation. Globally there must be a redshift, gravitational redshift during the fall, and that refers to the uncertainty principle by changing the gravitational potential with changing the radius during the fall. When the particle localised at a certain point in space same as in Pond and Renka experiment in this the decrease in the speed is given according to the reciprocal of the Lorentz factor where according to my equivalence principle is depending on the gravitational potential R^-1=(1-GM/c^2r) and in this case the group velocity and phase velocity are equal (linear dispersion, while during the fall when the gravitational potential changing when changing the radius, in this case the decrease in the light speed and also in the relativistic escape velocity of the free fall object is depending on the reciprocal square of the Lorentz factor where R^-2=(1-GM/c^2r)^2, and this factor gives you the group velocity according to the uncertainty principle. This factor is responsible for light bending by gravity, the precession, Shiparo delay, Pioneer anomaly. Now review my paper relative to the exact solution of the Pioneer anomaly...it is exact solution http://vixra.org/abs/1109.0058 This solution is according to the Schwarzschild Geometry, but according to the Schwarzschild Geometry is not a solution...while it gives an exact solution...why? Because of that it is resulted in GR the energy-momentum problem!!!!!! Because proponents of GR want to keep on objectivity and continuity, and no problem if there is energy momentum problem in gravity. Macro world according to GR must move according to objectivity and continuity better than solving the energy-momentum problem in physics and better than unifying quantum and GR. 

    Now when the particle fall in the quantum Schwarzschild radius GM/c^2r in the black hole, all the rest mass of the particle will change to photons, and in this case the particle will move in the escape velocity equals to the speed of light in vacuum locally. Globally the redshift will cause to measure the speed of light to be zero.

    Now the relativistic escape velocity locally according to my equivalence principle is

    vescape=(2GM/r-G2M2/c2r2)0.5 , substitute the quantum Schwarzschild radius GM/c2r  in the equation of  the relativistic escape velocity, you get vescape=c locally. 

    Now if you review carefully the square of the reciprocal of the Lorentz factor R^2=(1-GM/c^2r)^2= 1-2GM/c^2r-G^2M^2/c^4r^2 This is exactly 1-v2escape/cWhich agree completely with my equivalence principle, and with my transformation.

    Now you can understand completely the gravitational time dilation and the gravitational redshift and how the uncertainty principle working and there is no any energy momentum problem and everything is conserved. Furthermore according to that, there is no need to dark matter/energy, and there are no infinities.

  • Truman P Young added an answer in Species:
    1
    Do endemic species that grow only in restricred areas and are there considered as Native species without human intervention ?

    Endemic species  or Native species in the challenge of the human intervention in all the areas espcially in virgin forest where the exploration is active.

    Truman P Young

    Your question in not clear. This sounds like the definition of 'native species', but I do not what 'without human intervention' has to do with it.

  • Tony Maine added an answer in Photovoltaic Systems:
    5
    PV vs CSP solar technologies?

    The energy demand has increased exponentially during the last decade and should reach 50 TWh in 2050. It is admitted that in the future, renewable energy sources should replace fossil fuels and reduce GHGs emissions which are responsible of climate change. The huge solar potential  is pushing investments toward CSP and PV technologies [1]. The two technologies are now in an open competition but PV is still leading with a comfortable ranking as a third source of Renewable energy. CSP technology still needs technical and economical improvement although it’s thermodynamically consistent.

    Tony Maine

    I don't think there are many commercial, profitable CSP installations in actual operation. I know a number are planned, but as Haddad states, the cost often puts the investors off before construction even starts. I think it's a shame because CSP has a lot going for it, but until the cost issue is solved it can't become mainstream. PV plus batteries will in my view remain comfortably in front because of cost and simplicity.

  • Mohamed A. Mohamed added an answer in Climate Data:
    3
    What is the best data center to download any country or city climatic data?

    I am looking for a data center that provides freely available daily climatic data (mainly precipitation and temperature) for Jordan and Syria. I need past observed data up to now that is manipulated, and if these could be downloadable , the higher the resolution would be the the better . Thanks for any suggestions.

    Mohamed A. Mohamed

    Dear Alham 

    please check this site you can find your answer

    http://rratlas.kacare.gov.sa/RRMMDataPortal/en/MapTool

    Or 

    http://www.worldatlas.com/

  • Ahmed Abdelraheem asked a question in HFSS:
    New
    What is the optimum height of a Floquet-Port over a periodic structure?

    In the process of simulating a periodic HIS, a Floquet-Port needs to be assigned at an appropriate height over the surface. How much is that height supposed to be? and how can I be so sure of the results if any small change in this height dramatically changes the results??

    Also, do I need to use PML?

    P.S.: I am using HFSS

  • Omar Bouattane added an answer in Coordination:
    2
    How to get onclick coordinate pixel value and location from an image and form a vector?

    I have to form a vector of some clicked pixels of an image, having information about x, y coordinates and pixel value. I get x,y coordinates and pixel value from image. But forming a vector for n number of pixel positions is difficult. I am not getting how to form a vector?

    kindly help me for this problem.

    Omar Bouattane

    For a given image sized (n xn) , when you clicked on a point (x,y) where :

    x and y are between 0 and n-1 , you can use the row major identifier ID= x*(n-1)+y to locate this point on a linear vector. thus the pixel value will correspond to the component value of this vector.

  • Geraldo Carvalho Jr added an answer in Pearl Millet:
    1
    Can anyone provide me with SAS commande to estimate GCA and SCA effects and their significance for line x tester design?

    I have data for line x tester pearl millet hybrids evaluated across 3 locations in alpha lattice. (2 testers, 18 lines =36 hybrids). I have measured 13 variables

    Geraldo Carvalho Jr

    Hi Inoussa email me that I can help you with that. 

    Thanks, 

    Geraldo

  • JinYu Zhang asked a question in Autophagosomes:
    New
    Could anyone tell me how to observe the double-membrane of autophagosome with Transmission Electron Microscopy?

    I am trying to observe autophagosome in the starved MEFs cell by TEM (600,000x), but  I have never seen the double-membrane of autophagosomes. I  only saw a lot of single-membrane vacuoles. Look like there are no any double-membrane autophagosome at all. I really appreciate If you could tell me how to treat cells, collect the cells and fix them to get better TEM image for double-membrane autophagosomes. 

  • Rudolf Ritt added an answer in Social Networks:
    6
    Do scientists tend to gain preferably informations which confirm their opinion and fade out contradictory statements?

    I heard (Süddeutsche Zeitung, February 6/7th 2016), that people like to sit in a "reverberation chamber", they are consuming only informations which confirm their opinions, because it feels good to be liked or confirmed.

    The social networks tend to strenghten this behavior, especially with the help of new filter systems, which gain new connections by evaluating the personal data of the user.

    Is this contradictory to objective thinking and having an open mind?

    What about the filtering systems of RG?

    Rudolf Ritt

    @ Keith Robert: you said it's prevalent in politics and religions, especialy in this cases it would be essential to see also other point of views in order to prevent radicalism and terrorism!

    @ Jan: I probably think, RG is a Social Network, of course with an other focus. I see no danger to get no neglects of our theories, I already had not only one for myself :)

    @ Mario: I share your opinions about the advantages of RG or platforms like this!

  • Bushra Ismaiel asked a question in ns-3:
    New
    Can any one suggest me whether i should use NS-3 or Matlab for simulation. Which one is easier for implementation of PCF mac protocol in WLAN?

    Kindly email me at bismaiel@gmail.com

  • Phil Barbonis added an answer in Innovation Management:
    6
    What hypotheses would you formulate when you think about the relationship between managerial competencies and innovation?

    What impressions do you have when you think about the relationship between managerial competencies and innovation?

    Phil Barbonis

    Your question is unclear. What kind of managers do you have in mind: accounting/finance, HR, Marketing, Strategy, R&D/Engineering? What kind of innovation do you have in mind? Organizational innovation? Process/product innovation? Different managers will have different competences, I would think. At the outset, I think accounting has to follow very specific rules (e.g., national accounting standards, or even GAAP) that may preclude innovation. R&D/Engineering would be expected to be innovation-driven if a firm is to survive. Then, a review of the literature could help you to formulate interesting hypotheses. Anyway, here is one for you to consider: H0: Managerial risk-taking (behaviour) by funding R&D could lead to disruptive innovations.

  • Mohamed A. Mohamed added an answer in Energy Consumption:
    3
    What are the methodologies used to address high energy consumption and increased carbon dioxide emission within ICT devices.?

    my research topic Virtualization of Computing Technologies for Reduced Energy Consumption and Co2 Emission

    research methodology

    Mohamed A. Mohamed

    The following paper can help you 

    A novel smart grid theory for optimal sizing of hybrid renewable energy systems

    doi:10.1016/j.solener.2015.11.016

  • José Eduardo Jorge added an answer in Cultural Communication:
    40
    Kung Hei Fat Choi! Are you, your country, town or community celebrating the New Chinese Lunar Year of the Fire Monkey?

    In 2007, we have started an ongoing research project on “Globalization of Holidays and the Calendar”. In the beginning, we were only interested in trying to understand the rapid spread of holidays that, as Halloween and St. Valentine, didn’t have any cultural tradition in Chinese communities but became an important economic asset as well as festivals mobilizing casinos, hotels, restaurants, then schools and associations, nowadays firmly installed in social networks exchanges. Thereafter, we have also started studying the diffusion of public and private festivities of the New Lunar Chinese Year along with the growing economic presence of China worldwide. We have been systematically inviting Master and PhD students to research the topic and I would like to appeal to your collaboration. Can you give us information, pictures, videos or any other documents regarding the diverse celebrations of the Chinese New Year in our country, town or local communities? If there aren’t any commemorations at all, can you explain the situation? What do you think about this clear globalization, industrialization and marketization of holidays that, in some cases relatively new, are being celebrated among other cultures and communities? Is there a main economic driven factor or there also are much more complex cultural and social elements?

    José Eduardo Jorge

    Dear Ivo:

    In recent years, Argentina has received an important migratory flow from China. The Chinese "colectividad" --as are called here the diverse immigrant "communities" that, since the late nineteenth century, shaped the current population of the country-- stands out for its strong presence in the business of small supermarkets, which are very popular for their low prices .There's also a popular "Chinatown" or "Barrio Chino"  in Buenos Aires, where New Year celebrations attract many locals and tourists. 

    + 4 more attachments

  • Rob Catlett added an answer in Economic Efficiency:
    2
    How can I evaluate economic efficiency of diagnostic tests? Are there application models?

    Does exist a model to compare different kind of diagnostic tests? I would like to compare only diagnostic tests, not health prevention plans.

    Rob Catlett

    I am not we (others and me) others understand your question.  I often hear of the difference between statistical significance and economic significance.  For example, when assessing a program's effectiveness, some researchers report a statistically significant increase from the pretest to the post test.  Using hypothetical data I created for this answer, let's say scores increase from a 35.5 percent correct to a 38.7 percent correct and that this is statistically significant at the 0.05 level.  However, some might say that spending $x million dollars is economically significant, or some might call it economically inefficient because the gains are nearly what were expected.  

    I suspect my answer will help you do describe what you are seeking, which very well could have nothing to do with my answer.  Regardless, I hope it helps.

    Rob

  • Dirk Enzmann added an answer in Exploratory Factor Analysis:
    6
    I have binary variables which I want to use in an exploratory factor analysis. I am using STATA vs13. and have tried tetrachoric correlation?

    I have 13 binary sleep variables which I want to use in an exploratory factor analysis to determine whether there are underlying latent variables explaining the correlations between variables. I understand that adjustments are required to the factor analysis process for binary variables. I have tried tetrachoric correlations but keep being told there is missing data in my tetrachoric matrix in STATA. Has anyone ever done this or come across the use of factor analysis with dichotomous variables? 

    Dirk Enzmann

    The quasi-continuous assumption is pivotal to estimate tetrachoric correlations: The tetrachoric correlation tries to estimate the correlation of two continuous variables artificially dichotomized (see the the MacCallum et al. (2002) article mentioned in my first reply.

    BTW: In addition to factor analysis, it may also be sensible to have a look at a Mokken scale analysis of your data, see -findit msp- in Stata. As you are seem to have missing values, additionally, you could have a look at -imputemok- (again, via -findit imputemok-).

    Best,

    Dirk

  • Ebrahim Sangsefidi asked a question in Abaqus:
    New
    How to model elastoplastic behavior of soils in ABAQUS?

    I need to know how can I provide input parameter of ABAQUS for modeling viscoelastic behaviour of soils. Is there any laboratory test for this matter?

  • Ali Karakaş added an answer in EFL:
    1
    Does anybody know of any studies that looked at the production/perception of /r/-liaison ('linking' /r/ and 'intrusive' /r/ by EFL learners?

    I'm interested in differences in the use of /r/-liaison between native speakers of non-rhotic English (e.g. RP) and the use of that phenomenon by EFL learners.

    Ali Karakaş

    Dear Jose,

    You might have a look the article on the /r/ sound by following the link below:

    https://www.researchgate.net/publication/271881229_WhichrAre_you_Using_as_an_English_Teacher_Rhotic_or_Non-Rhotic

    Hope you find it useful! 

    Ali. 

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: There are many obvious differences between North American English (NAE) and British English (BrE) /r/ phoneme, and a great majority of Turkish English teachers do not know which variant of the /r/ they are using. It must be noted that such a case easily confuses the students. The articulation and production of North American English-r is ambiguous. In terms of articulation and pronunciation, NAE is also referred as General American (GA), and BrE is accepted as Received Pronunciation (RP). The American-r phoneme, whose IPA sign is [x], which is a retroflex case of pronunciation, also called a flap, represents a very serious setback in teaching standard American pronunciation to Turks. As opposed to this, the BrE-r is a tap whose articulation is very close to Turkish-r word-initially and intervocalically.
      Full-text · Article · Dec 2012 · Procedia - Social and Behavioral Sciences
  • Tony Maine added an answer in Philosophy Of Science:
    4
    Under which conditions does new scientific knowledge enter the social sphere and become common sense?

    Can someone recommend me an article or book concerning this question? In different words: What are social acceptability conditions for scientific knowledge? I already scanned through Kuhns Structure of Scientific Revolutions but I somehow feel like he stays in the scientific ivory tower and does not discuss the question of how scientific revolutions influence the civil society, create social movements or change the behavior of people.

    Thanks!

    Tony Maine

    Laura, I looked at the abstracts of the papers Joyce suggested and while they are clearly thorough and well researched, don't in my view quite answer your question. I am more of the opinion of Renzo, that the conversion of scientific knowledge into common sense is rare, if not non-existent. Common sense is, I believe, a combination of countless facts learned during one's growing up, combined and 'cross indexed' via an extremely clever interconnection system in the brain. Not one scientific fact in sight! Only very recently have children had their hands on devices that go substantially beyond the pen-and-paper environment of the last few hundred years.  While the internal operation of tablets, phones and the like are based on extremely hard won technological progress, and exist close to the cutting edge of what is possible, it isn't clear to me that the uses to which these devices are being put in any way inspires the children using them to incorporate scientific knowledge into their day to day activities. If only it did!

    Going back some hundreds of years, consider the discoveries of great scientists like Newton, Galileo, Copernicus, Kepler and their peers. The laws of motion (at non-relativistic speeds) were well understood and used to make accurate predictions of moving bodies on earth and in space. But to what degree has such knowledge been formally incorporated into society? We already knew how to throw and catch things, which involves calculations that only now are being matched by simple AI/robotic devices. And as far as Einstein, Planck, Minkowski and their peers are concerrned - forget it!!

  • James Carrillo added an answer in Dioxygenases:
    9
    How can I determine a cofactor for an inactive enzyme?

     I am having issues restoring activity to an extradiol dioxygenase that I am studying.  It is a recombinant form of a Rhizobium enzyme, expressed with a N-terminal 6xHistag in E. coli BL21 cells.  I suspect that the Histag is somehow responsible for inactivity and I am in the process of cleaving it using thrombin.  

         I can't help but thinking that I am overlooking the fact that a cofactor is required by the enzyme.  The same enzyme has been shown to work using the cell lysate and although my goal is to be using purified protein I can't even get the cell lysate to work.  It is my understanding that LB media is supplemented enough to provide minute amounts of possible cofactors for growth.  Additionally I supplemented the LB media with 1mMFeCl2 (ferrous iron binding site on enzyme) and still no activity.  Previous work on this enzyme involved growing in YEM broth, which I can't imagine making a big difference.

    Would using YEM media over LB make any difference in activity of my enzyme?

    How does one usually determine which cofactor is required for an enzyme?  Besides looking for conserved metal binding domains is it a good idea to create a cofactor "cocktail" and use that to determine activity?

    Thank you for any words of advice.

    James Carrillo

    I don't have the purified enzyme from Rhizobium....I may be able to dig up the particular strain of Rhizobium in the freezer but that wouldn't help.  It is possible for me to do ICP-MS but I doubt that would help either because my enzyme is not active.

    Is it unlikely that the cell culture and pure protein requires a metal cofactor to be present all through cell growth, translation, and purification?  I assume that it is sufficient to provide the cofactor in the assay mixture...I've been using a small amount of Ferrous sulfate (100uM) and aspartic acid because the substrate chelates iron.

    I think ferrous sulfate is doing the trick, still working on confirming that though...

  • Alireza NikSejel asked a question in Zoning:
    New
    In the seismogenic zone of crust there is a increase of peripheral resistance Proportional to the depth, why??

    hi everyone

    in the seismogenic zone of crust there is a increase of peripheral resistance Proportional to the depth, why?? 

    what about the seismogenic zone beneath the moho in the mantle??? 

  • Endang Wahyu Pamungkas added an answer in Computer Science:
    2
    What are the hottest research areas in computer science?

    can someone tell me research areas in computer science.

    Endang Wahyu Pamungkas

    Yes I agree with Mr. Harry Achsan. Now, I interesed in Machine Learning for Information Retrieval.

  • Dmitry Zhdanov added an answer in Structural Dynamics:
    2
    How to find the torsional vulnerability of a 2-storey building based on center of resistance?

    This 2 storey building's layout is attached in the attachments. Here the architect wants to remove the column C (in the ground floor) and add a wall only from C to D. So this wall exist in the ground floor only. Based on this information, how do we check the torsional vulnerability for the whole building based on the center of resistance?  

    Dmitry Zhdanov

    The idea to build another wall in order to minimize the torsional effects on the building suggested by George is pretty good. But i think its better to construct it in the same direction (along x axis) at the opposite side of building (see pic). In this way the center of mass and the center of rigidity will be rather close to each other.

  • Parijat Ray added an answer in Chlorides:
    2
    Can anyone advise me on the reaction conditions of methacrylol chloride with alcohol?

    I want to prepare acrylic monomers from alcohols by reacting with methacrylol chloride. Can anyone provide me the reaction conditions or suggest me any literature where I can find that? Thanks in advance

    Parijat Ray

    Thanks Steven for the help. I m grateful.

  • Cole Peters added an answer in Western Blot:
    7
    Can anyone help with a problem with actin immunoprecipitation?
    I did IP by mouse monoclonal actin antibody to check protein X under cytoskeleton inhibitor treatment and found that cytoskeleton inhibitor can decrease the interaction between actin and protein X. But when I used protein X antibody to do IP and checked the actin under the same treatment, I got the opposite results that mean cytoskeleton inhibitor can decrease the interaction between actin and protein X.

    I repeated several times and got the same results. I used the IP lysis buffer containing 1%TritonX-100,150mM NaCL, 10mMTris PH7.4, 1mM EDTA PH8.0, 1mM EGTA PH8.0, 0.2mM sodium orthovanadate, 0.5% NP-40,100 x cocktail protease Inhibitor. Can anyone explain why the results are opposite and tell me what I can do to solve this problem? And I don’t know if I can do IP by crosslinking and which crosslinker I should choose. Thank you very very much for your answer.
    Cole Peters

    What actin antibody did you use for IP? Im looking for a good control IP Ab

  • Louis Brassard added an answer in Philosophy of Social Science:
    25
    Praxis versus academic noises?

    Karl Marx states in "Theses on Feuerbach" that "The philosophers have only interpreted the world in various ways; the point, however, is to change it." (Thesis Eleven) I must admit that I'm all the more persuaded by that statement as time goes by. When was the last time you heard voices of conviction and righteousness oozed out from academia and how often do you see an academician get his/her hands dirty?

    If you want to get you hands dirty, here's a link:

    https://www.change.org/p/researchgate-researchgate-violation-of-freedom-of-speech-and-scientific-freedom

    Hm, I guess this post so far has not been qualified as a question. So let me ask this: what do you think of Marx's Thesis Eleven in "Theses on Feuerbach"?

    Louis Brassard

    Carmen,

    Yes the responsibility is diffuse and except for the small criminals, and the leaders on the looser side of a war, nobody is responsible in the cog world.  Everybody follow order , it was said by all the accused in the Nuremberg tribunal.  Everybody due his duties in our societies and nothing more.  Diffusion of responsibility, separation of the tasks is not a conspiracy but the most efficient way to organized large scale hiearchical societies and that since at least 60000 years.  A good example of this diffuse responsibility mind set is the reaction of the public to someone lying unconscious on the sidewalk.  In a village or small town everybody stop and try to do something.  In big city everyboddy continue walking and pretend to have seen nothing.  If nobody care then there is something wrong with this guy but there is so many people around why should it be me.

  • Malur Srinivasan added an answer in Mechanical Engineering:
    5
    When cooling a nodular iron (or any steel) roller with water,considering the Leidenfrost effect, what is more important: volume or velocity?

    Steel mill roller used to shape the steel.

    Malur Srinivasan

    https://en.wikipedia.org/wiki/Leidenfrost_effect#Heat_transfer_correlations

    If you look at the correlation developed by Hsu and Westchester (reference 10 in the abovementioned source) you will find that the heat transfer coefficient under Leidenfrost effect is directly proportional to the mass flow rate of cooling water. The latter in turn is directly proportional to volumetric flow rate which is a function of the velocity. The question is : are you looking for increase or decrease heat transfer? Increase in water flow rate will result in faster cooling of the roll. This may however bring in the risk of martensite formation and possibility of roll cracking. Decrease in water flow rate may avoid this problem but give rise to rolls being too hot with attendant production problems. This suggests that an acceptable mass flow rate will have to arrived at based on these considerations.

  • William F. Hansen added an answer in Agronomy:
    11
    Can i estimate the water table with an total station or another measuring instrument?

    A florestal inventory was conducted in 42 plots of 5-25 meters, distributed in seven lines going through three compartments, in order: 1) A floodable plain forest in a organic soil; 2) Intermediary assembly located in a soil with a steep slope; and 3) a dry forest located in the highest place, with poor white sand soil.

    For now, i intend to evaluate the water table variation to perform multivariate analyses involving plant community and soil water content. Initially, would be interesting install 42 piezometers, 1 per plot, but this would be very difficult and expensive to perform.

    Therefor, i have thought in install a minimum number of piezometers per area (compartiment) and estimate the water table variation of the other plots by the use of a total station or another measuring instrument.

    I would appreciate to know if this methodology would be valid, and if there is any article that could support this idea.

    William F. Hansen

    The Hobo is self contained unit, and it's transducer measures pressure of the water above its installation, plus the air pressure, so the readings may need to be corrected by barometric pressure. The technology may have figured out a way to correct without the barometric pressure.  Ask the company.  If it needs to be corrected, just buy an extra unit and keep it in the air, or they may have one for use in the air.  One barometric detector is probably enough for your entire study area.  Perhaps the instructions for the Hobo are on the website.  If the newborn city's is close enough, that might work, but check with Hobo representative or materials.  When you lower you Hobo to a specific depth of below the permanent water table depth, it will log the depth changes with time and as indicated if not automatic, the air pressure will need to be corrected.  This is relatively easy in Excel.  Each time unit has its full water plus air pressure, and you just subtract out the air pressure to end up with the water pressure that yields depth.  

    I just started the Researchgate, so I am still learning what it can do.  I will try to get into your map when I am on a normal computer.  I just bought a 23 inch high definition monitor, so at may help.  I have become quite good at reading and understanding the ground and try to decipher the story it has for me.  I have become interested in your study in a far off land, and am glad I can help you out, and perhaps I will have time to check in with you.  I would have a lot to learn on differences at or below the equator.

  • Sandra L. Arlinghaus added an answer in Google Earth:
    3
    Between landsat and google earth images which one can give better results with regards to fine scale disturbance studies?

    topic is one fine scale disturbance of woody vegetation in savanna ecosystems 

    Sandra L. Arlinghaus

    When using Google Earth images over time, be careful, because the images from earlier versions may not align properly if overlain on contemporary images of the same location.