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Spatial Data Infrastructure - Science topic

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Dear Researchers,
We are trying to implement semantic Geospatial data infrastructure and want to use OWL files with Geonetwork.
Any hint on how to link ontology files with Geonetwork will be greatly appreciated.
Thank you very much for your time.
Regards
Ali Madad
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Dear Researcher,
Please refer to the below links for GeoNetwork Metadata plugins @ OWL Resources. I think this might be helpful.
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Dear all!
I would like to suggest you take the survey "NSDI FOR YOU AND YOUR COUNTRY":
The results of this survey will help me to research the issues of the implementation of NSDI and get an overview of this policy.
I will be very grateful for your help, cooperation and sharing!
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Indeed, good start
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As you probably know the concepts of Spatial Data Infrastructure (SDI), National SDI (NSDI), Urban SDI, Gloabl SDI (GSDI). The question I have is that how we handle the relationship between NSDI and Urban SDI. You know there is resolution/detail/purpose difference between NSDI and Urban SDI. However, there has to be coherency between NSDI and urban SDI to continue the services of central government and local government. Please describe and give me some resources about how to bridge NSDI and urban SDI to provide interoperability.
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We need to look into complete landscape in an ecosystem
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Spatial Data Infrastructure (SDI) or Geographical Data Infrastructure (GII) is known for sometimes for providing the need for spatial science research as well as many other purposes in science and practice. I am looking forward to the further explanation on the question around - how does the contemporary topic of "Research Data Infrastructure" on spatial science will make a difference in regard to "SDI or GII"?
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Spatial Data Infrastructures provide a platform that offers an interaction between spatial data, with networks, standards and policies. This framework can be used to develop institutional arrangements, legal and political tools, social resources to facilitate the integration of spatial data and its maximum potential use. To do this, there must be a channel involving data providers, resellers and users, helping to interact with technical, policy and standards tools to coordinate and use the data correctly. SDI offers minimization of costs and time when integrating data from multiple sources. However, this has not yet been achieved. More research is needed to achieve efficient data integration in the context of the SDI project; the results can assist in the development of technical, political, institutional and management tools. When this is achieved, data integration will facilitate sustainability.
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Dear Prof Edson Augusto Melanda,
Old version of WEKA means? Ver 3.0?
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After the geometric correction, i am obtaining negative values in remote sensing reflectance (Rrs). Can someone explain the reason for it? Is there any scientific significance for negative values in Rrs? 
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Hi Srinivas,
Which atmospheric model have you used ? for which images ?
If you have a very low radiance value (i.e. pixels in shade), then the atmospheric model you use could not be able to model the reflectance accurately and you can get some negative reflectance values. It just means for those pixels, the results are unreliable and therefore should be excluded.
I got the same problem with SPOT4 images, negatives values in few pixels in Red band and very high values (saturated pixels) in NIR band, we have excluded the negative values , see fig.8 in my paper:
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It is very common that people describe the resolution in their orientation maps using the pixel/step size value used during mapping.  This is fine when the pixel/step size value is larger than the lateral spatial resolution for that measurement but what could happen if one decreases the step/pixel size value well below the spatial resolution for instance when analyzing ultrafine grained materials? Would this be correct or would such a measurement make sense?
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Yes, I think it would still make sense, one would just have to be careful in analysis to not equate x and y distances with z distances (in a DEM, for example). If I'm understanding you correctly, this situation is actually very common - DEMs are frequently at much higher vertical/pixel resolution (e.g., single feet or meters) than they are at horizontal resolution (e.g., 30m cells).
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       When we want to do classifying in the choropleth map, the first question is to determine the number of classes. And the rule 2^n<=x<=2^(n+1) is usually to determine the number of classes. I.e. if there is 70 cities in a region ( i.e. a state), if we want to detect the pattern of population distribution in these cities, we could divide these cities into 6 classes using the above rule. Details: 2^6=64, 2^(6+1)=128, and 64<70<128, so the best number of classes is 6. That is n=6, x=70 (the count of cities).
      I forget who first put forward this rule. Can anyone help me to provide the reference about this rule?
Thank you very much!
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City sizes are heavy tailed or right skewed, so the best classification method is head/tail breaks, with which both number of classes and class intervals are automatically determined - "the data speaks for itself". As you can see from the following image, to the left is the result of the head/tail breaks, while to the right is the result of the natural breaks. Obviously, the left reflects the underlying scaling pattern of far more small cities than large ones.
Jiang B. (2013), Head/tail breaks: A new classification scheme for data with a heavy-tailed distribution, The Professional Geographer, 65 (3), 482 – 494.
Jiang B. (2015), Head/tail breaks for visualization of city structure and dynamics, Cities, 43, 69-77.
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As I am digitizing polygons in 10.2 ArcGIS, sometimes the vertices are getting deleted automatically and also it does not close as it should by clicking on the last vertex. 
2. The final product has an altered shape that it takes on its own.
3. Even while editing vertices as I add a new vertex it deletes the previous one.
4. Also, I tried converting from lines to polygon. That also does not match exactly.
I am frustrated. Any help would be appreciated. 
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Thank you for replies. It was because I had not defined spatial reference frame. Defined it and now it is working.
Though that was not a problem with earlier versions.
Thanks again.
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In developing countries, it is difficult to find mentor/supervisor for PhD students who want to pursue their research(s) in new areas such as VGI, SDI, Spatial Data Mining, Spatial Agriculture, m-governance and crowd sourcing etc. The reasons include brain drain. Therefore, to reduce digital divide in a sense, researchers/scholars/institution who can contribute to advise students especially of developing countries voluntarily are requested to help out.
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Yes, there are volunteers to be advisors if not supervisors for PhD students in developing countries. I agree with this statement and also @ Prof.Olena Dubovyk, @ Pro. John Jennings and @Prof.João Paulo Hespanha answers all are very nice one.
Thanks Prof.Asmat Ali for your valuable question please. 
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3D Cadastre Discussion 1:
Hi everyone, I am starting a discussion on various topics on 3D cadastre. Each week I will post a new discussion topic, but you are welcome to comment on previous topics as well. The aim of these discussions is to share ideas on individual or jurisdictional experiences in 3D cadastre. For each discussion topic, once there are a fair number of responses, I will summarise them to close off the topic.
The first topic to kick off: why do we need a 3D cadastral database? Are we better off with the current arrangements of 3D plans stored in a 2D database or is there a distinct advantage in investing in a database that is able to store 3D objects? Please share your thoughts.
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This question could be turned around to “Why not?” Queensland is not the most urbanised place in the world, but has thousands of 3D parcels registered in the Cadastre. Looking at a small area of the Brisbane CBD, there are over a thousand 3D parcels, but only about 600 2D parcels.
A database would always be considered whenever a collection of many thousand objects needs to be recorded and maintained. The question then is “Is a separate 3D DCDB database the best approach, or a single DCDB for 2D and 3D parcels?” Further questions arise then: “how much detail is needed? and “how do we visualise the 3D parcels” etc.
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I am looking for papers and/or descriptions on how one can establish a national level satellite archive with support for pixel level extraction (querying) as well as full imagery. We are looking at depositing national level (+400.000 km2) satellite imagery from Sentinel 2 and Landsat 8 as well as relevant in-situ data for further analysis. This is on an idea level now, but to consider if it could be done it is necessary to look at experiences on how this theoretically could be done.
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We are currently investigating the effect of open topographic data in The Netherlands and like to compare our findings with results from other countries
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I think Norway & US, Sir.
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Thanks.
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One research direction out of many is accessibility issues of geoportals
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Please give me your ideas, how social innovation and social validation could contribute to SDI building.
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@Karel Charvat good to see you here.
Indeed SDIs have social dimension because at the end of the day these are meant to deliver benefits to social communities. Local knowledge that will come though social groups would help not only to validate the specific needs of an SDI and its rationale for a particular region and but also to fetch innovations from the region itself.
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Data Size : approx 50 tb, users: approx 50 users with desktops connected to each other, currently no server hardware.
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Hi
You can use a PostGIS database cluster and use Slony PostgreSQL product for replication ( http://slony.info/ ) You need a server operating sistem and hardware to make data available to the clients. For that amount of data I think you will need a server
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I modeled urban growth in a city for 4 different scenarios. How to optimize the results of the modeled land use in (say) 2025 and choose a best one? Basically, I want to evaluate the scenarios quantitatively. I have the city master plan demand for 2025. Is it good just to compare the results with the master plan map or we can adopt any other method?
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Dear Chitrini,
I think that you should carefully differentiate two types of scenarios:
1. Exploratory scenarios (what could happen?)
2. Normative scenarios (what is your desired future?)
As far as I understand, you have developed 4 exploratory scenarios and you have one plan, which could be seen as a normative scenarios. Comparing both products can obviously be useful, but please keep in mind that the master plan has been developed by someone with some kind of exploratory scenario (probably a Business As Usual) in mind. As such, you are comparing apples and pears. An explanation of the method that I have used can be found in:
Kok, K., van Vliet, Bärlund, I., M., Dubel, A., Sendzimir, J. 2011. Combining participative backcasting and explorative scenario development: Experiences from the SCENES project. Technological Forecasting and Social Change 78(5): 835-851.
I hope this is helpful!
Kasper
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Is "planning as a science" a real problem? How can we build a scientific approach to planning?
Town planning and regional planning are normally considered as techniques of public administrations, or as a part of the architecture (urban design). The Italian concept of Urbanistica at the same time means both analysis and planning, both at local and territorial level, and not only urban land use. Don't worry, I Know that in Italy (but not only here) theory and practices are very different. I think we must develop the scientific aspect of planning (as in urbanistica concept), using carrying capacity, urban metabolism, ecological footprint and so on. That is to say we need the planning as an autonomous science, capable of studying the anthropic transformations and of directing technical applications. Many people do not agree with this statement, notwithstanding, just one example, the UE European Green Capital Award. In ECGA we really find applied these concepts. Land use and rights to property seem to be untouchable (all do remember Garret Hardin, but few Elinor Olstrom). Every nation has a specific view of planning in laws and in practices. Every one has his definition for planning (urban-, social-, physical-, rational-, comprehensive- planning, aménagement du territoire, urbanisme, stadtplanung, raumplanung, urbanistica and so on). So it is nearly impossible to compare plans, choices and technical regulations on zoning and land use, and also assess the environmental impacts. Is it also a problem of Spatial Data Infrastructures?
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Hola Luca!
Chile como caso de planificacion es un mal ejemplo, muy malo. Planificacion territorial no existe, solo urbana, limitada al area urbana de las ciudades. Hay supuestamente 3 niveles de planificacion, que coinciden con los 3 niveles administrativos: PRDU (Plan regional de desarrollo urbano), PRI (Plan Intercomunal) que agrupa varias comunas, y el PRC (Plan Regulador Comunal). Tambien hay algunos planes menores que se llaman Seccionales.
Luego en el resto de AL la situacion cambia mucho, desde paises con regimenes de planificacion bastante desarrollados, a otros casos donde practicamente no existe planificacion. Diria que el denominador comun es una necesidad de mejores capacidades tecnicas en la mayoria de los paises de AL, agravado por procesos de urbanizacion muy rapidos. Volviendo a tu pregunta original, lo de la una nueva ciencia urbana que comentabamos esta todavia a añoz luz de la planificacion "cotidiana"... el soporte "cientifico" con que se estructuran las decisiones es en la mayoria de los casos muy pobre...
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Could you compare WFS and KML standards? What are the advantages and disadvantages of both?
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I'm not sure that we can compare KML and WFS.
KML is a format just like GML, JSON, CityGML, Shapefile, etc, but WFS is a service. For example WFS outputformat can be GML, Shapefile, JSON, CSV and so on, I assume also KML is possible.
We can compare KML vs GML, JSON, CSV, Shapefile and other formats.
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I want to know how I can fill the data gaps in Landsat SLC off data using Erdas 9.3 software. I tried the ArcGIS extension tool, but it removes the data gap portion and thus distorting the geometry of the Image.
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Hi plz find attached gmd model if u need more in more info regarding gap filling fell free to ask
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I'm looking for the geodata for Bangladesh. Looking for some suggestions.
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Thanks for the information.