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  2. geothermal detection, you can use thermal based images from satellites, many product offer this, you can search any images with infrared bands. something like this ; http://www.asiageospatialforum.org/2011/proceeding/pps/Mona%20Natalia_AGF.pdf many research papers talk bout this topic if you want to compare, then simply using multi temporal images, happy learning
  3. if you bootcamp it then its more than enough IMO if you plan to virutalize it in mac for example parallels then that is not enough. why dont you upgrade the ram to 8 gig. ram is cheap nowadays anyway.
  4. If you are referring to the simple "dehaze" options in Erdas, then you shouldn't expect perfection. Depending on the source and particulate, some haze cannot be removed. If you are referring to atmospheric correction of Level 2A, then you should be using Sen2Cor. http://step.esa.int/main/third-party-plugins-2/sen2cor/
  5. Yesterday
  6. @3dbu @stuart1974 I'm starting out in a beginner GIS class and I want to use the free boot camp option for using windows on my mac. Do you think having 1.3 GHz Intel Core i5 + 4GB 1600 MHz DDR3 of processing power and memory is ok?
  7. Thanks! I'll have a look on it.
  8. Hello! I am new to the GIS world and as such have very limited knowledge of image analysis. My interest lies in identifying geothemal springs and mapping them. Large springs like Grand Prismatic Springs in Yellowstone can be observed on thermal imagery as seen in the attachment below (red arrow on the left). It creates a reproducible thermal "fingerprint" year after year. Does anyone have any suggestions regarding how to best scan/detect these thermal "fingerprints" over a large area. Is there software that will automatically compare images for these "fingerprints"? Perhaps something like this automatic landslide detection that compares images and indicates the probability of a Geothermal spring? Any guidance would be greatly appreciated! Ivan
  9. Check the Script of multi ring buffer: """---------------------------------------------------------------------------------- Tool Name: Multiple Ring Buffer Source Name: MultiRingBuffer.py Author: Environmental Systems Research Institute Inc. Required Arguments: An input feature class or feature layer An output feature class A set of distances (multiple set of double values) Optional Arguments: The name of the field to contain the distance values (default="distance") Option to have the output dissolved (default="ALL") Description: Creates a set of buffers for the set of input features. The buffers are defined using a set of variable distances. The resulting feature class has the merged buffer polygons with or without overlapping polygons maintained as separate features. ----------------------------------------------------------------------------------""" import arcpy import os import locale # Define message constants so they may be translated easily msgBuffRings = arcpy.GetIDMessage(86149) # "Buffering distance " msgMergeRings = arcpy.GetIDMessage(86150) # "Merging rings..." msgDissolve = arcpy.GetIDMessage(86151) # "Dissolving overlapping boundaries..." def initiate_multi_buffer(): """Gather arguments and set up for createMultiBuffers""" # Get the input argument values in_features = arcpy.GetParameterAsText(0) output = arcpy.GetParameterAsText(1) distances = arcpy.GetParameter(2) unit = arcpy.GetParameterAsText(3) if unit.lower() == 'default': unit = '' field_name = checkfieldname(arcpy.GetParameterAsText(4), os.path.dirname(output)) dissolve_type = arcpy.GetParameterAsText(5) outside_polygons = arcpy.GetParameterAsText(6) if outside_polygons.lower() == 'true': side_type = 'OUTSIDE_ONLY' else: side_type = '' create_multi_buffers(in_features, output, distances, unit, field_name, dissolve_type, side_type) def checkfieldname(field_name, workspace): """Validate field name on the workspace as needed""" if field_name in ['#', '']: return "distance" else: out_name = arcpy.ValidateFieldName(field_name, workspace) out_name = out_name.replace(' ', '_') if out_name != field_name: arcpy.AddIDMessage('WARNING', 648, out_name) return out_name def lower_license_union(feature_classes): """If Union is not licensed for more than 2 inputs at a time, perform Unions in batches""" union_fc = None tmp_fc = arcpy.Union_analysis( feature_classes[0:2], arcpy.CreateUniqueName('union', arcpy.env.scratchGDB))[0] for fc in feature_classes[2:]: if union_fc: tmp_fc = union_fc union_fc = arcpy.Union_analysis( [tmp_fc, fc], arcpy.CreateUniqueName('union', arcpy.env.scratchGDB))[0] # Delete intermediate data once used by next Union try: arcpy.Delete_management(tmp_fc) except arcpy.ExecuteError: # Don't fail for a delete issue pass return union_fc def create_multi_buffers(in_features, output, distances, unit, field_name, dissolve_type, side_type): """Main multiple ring buffer routine""" # Establish place holders for data cleanup buffer_list = [] union_fc = None try: # Loop through each distance creating a new layer and then buffering the input. # Set the step progressor if there are > 1 rings if len(distances) > 1: arcpy.SetProgressor('step', '', 0, len(distances)) step_progressor = True else: arcpy.SetProgressor('default') step_progressor = False # Buffer the input for each buffer distance. If the field_name is different than # the default, add a new field and calculate the proper value for dist in distances: if step_progressor: arcpy.SetProgressorPosition() arcpy.SetProgressorLabel(msgBuffRings + '{}...'.format(dist)) buf_distance = '{} {}'.format(dist, unit) buf_output = arcpy.Buffer_analysis(in_features, arcpy.CreateUniqueName('buffer', arcpy.env.scratchGDB), buf_distance, side_type, '', dissolve_type)[0] buffer_list.append(buf_output) if field_name.lower() != 'buff_dist': arcpy.AddField_management(buf_output, field_name, 'double') arcpy.CalculateField_management(buf_output, field_name, dist, 'PYTHON') arcpy.ResetProgressor() arcpy.SetProgressor('default') arcpy.SetProgressorLabel(msgMergeRings) if dissolve_type == 'ALL': # Set up the expression and codeblock variables for CalculateField to ensure # the distance field is populated properly expression = 'pullDistance({}, '.format(distances) for fc in buffer_list: expression += '!FID_{}!, '.format(os.path.basename(fc)) expression = expression[:-2] + ')' # If we have a full license then Union all feature classes at once, otherwise # Union the feature classes 2 at a time if arcpy.ProductInfo().upper() in ['ARCINFO', 'ARCSERVER'] or len(buffer_list) < 3: union_fc = arcpy.Union_analysis(buffer_list, arcpy.CreateUniqueName('union', arcpy.env.scratchGDB))[0] codeblock = '''def pullDistance(distL, *fids): return min([i for i, j in zip(distL, fids) if j != -1])''' else: union_fc = lower_license_union(buffer_list) codeblock = '''def pullDistance(distL, *fids): return min([i for i, j in zip(distL, fids) if j == 1])''' arcpy.CalculateField_management(union_fc, field_name, expression, 'PYTHON', codeblock) # Complete the final Dissolve arcpy.SetProgressorLabel(msgDissolve) if dissolve_type.upper() == 'ALL': arcpy.Dissolve_management(union_fc, output, field_name) else: # Reverse the order of the inputs so the features are appended from # largest to smallest buffer features. buffer_list.reverse() template = buffer_list[0] sr = (arcpy.env.outputCoordinateSystem or arcpy.Describe(template).spatialreference) arcpy.CreateFeatureclass_management(os.path.dirname(output), os.path.basename(output), 'POLYGON', template, 'SAME_AS_TEMPLATE', 'SAME_AS_TEMPLATE', sr) for fc in buffer_list: arcpy.Append_management(fc, output, 'NO_TEST') if arcpy.ListFields(output, 'buff_dist'): # Remove duplicate field arcpy.DeleteField_management(output, 'buff_dist') # Set the default symbology params = arcpy.GetParameterInfo() if len(params) > 0: params[1].symbology = os.path.join(arcpy.GetInstallInfo()['InstallDir'], "arctoolbox\\templates\\layers\\multipleringbuffer.lyr") except arcpy.ExecuteError: arcpy.AddError(arcpy.GetMessages(2)) except Exception as err: arcpy.AddError(err) finally: if buffer_list: for fc in buffer_list: try: arcpy.Delete_management(fc) except arcpy.ExecuteError: # Don't fail for a delete issue pass if union_fc: try: arcpy.Delete_management(union_fc) except arcpy.ExecuteError: # Don't fail for a delete issue pass if __name__ == '__main__': initiate_multi_buffer()
  10. Many thanks, Lurker, I'll give it a try!
  11. If you are talking about the google maps layer then the answer is no as its a cached with the labels already added I believe. If its imagery layers, then yes. Just use the aerial layer and not the hybrid layer. Google terrain layers do not have labeling as well.
  12. Hi all, I need some help with python code and buffer in ArcGIS: A set of polygons (all in one featureclass, circular shapes) should get several buffers (e.g. 40 times). Each feature gets a different buffer distance, it is stored in corresponding field in attribute table. So the first buffer distance is taken from value in table, the following are calculated by "buffer*i", "i" is counting from 1 to 40. For example: If first feature has the value 400 metres, first buffer for that feature would be 400 metres, 2nd 800 metres, 3rd 1200 metres,.... (measured from the origin shape). I had two attempts, both are not working the way I like: import arcpy arcpy.env.workspace = r"R:\Base.gdb" fc = "export" fieldname = "Buffer" i = 1 while i <= 40: outName = fc+"_" + str(i) dist = (fieldname)*i arcpy.Buffer_analysis(fc, outName, dist) i = i+1 Result: First Buffer OK, then abortion, because cannot find fieldname "BufferBuffer" (sure, multiplication of fieldname, but how to calculate with value and not with the name?). import arcpy arcpy.env.workspace = r"R:\Base.gdb" fc = "export" fieldname = "Buffer" cursor = arcpy.SearchCursor(fc) row = cursor.next() i = 1 while i <= 40: outName = fc+"_" + str(i) dist = row.getValue(fieldname)*i arcpy.Buffer_analysis(fc, outName, dist) i = i+1 Result: No Abortion, but all buffers are calculated based on one value from first feature in attribute table, not the corresponding. In case of using QGis, there are some plugins for multiple buffer, but they work just with static values. Maybe it's just a short fix in code, who could help me?
  13. what level for your data? do you mean you try to run atmospheric correction and failed? please describe what you refer as "fail" what did you do?
  14. Could you give me some advice how to do radiometric/atmospheric correction in ENVI ? Thanks
  15. Dear all Could you give me some advice to improve Sentinel-2A image look better? I would like to remove some hazed and make them clear looking. I try a lot in ENVI and Erdas, but fail. thank all of you in advance
  16. silahkan, selamet bergabung
  17. the best bet if you find free data programs, you submit a research and get the data, I saw once Tandem-X offer this programs. for now, a completely free DEM data stuck in 30 m resolution, anyone have another update maybe? hey tandem-x have a general proposal programs, maybe you can try it : https://tandemx-science.dlr.de/ scroll down
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  19. Hi, I am searching for DEM source for south east asia (Vietnam, Laos, Cambodia). Problem is that I need a better accuracy than 1 arc/sec, so SRTM / Aster is a nogo. This is for a non commercial simulation project. It would be great if someone could someone point me to a good source. Thanks, CH66
  20. Aggregated Indices Randomization Method (AIRM) Analytic hierarchy process (AHP) Analytic network process (ANP) Best worst method (BWM) Characteristic Objects METhod (COMET) Choosing By Advantages (CBA) Data envelopment analysis Decision EXpert (DEX) Disaggregation – Aggregation Approaches (UTA*, UTAII, UTADIS) Dominance-based rough set approach (DRSA) ELECTRE (Outranking) Evaluation Based on Distance from Average Solution (EDAS) Evidential reasoning approach (ER) Goal programming (GP) Grey relational analysis (GRA) Inner product of vectors (IPV) Measuring Attractiveness by a categorical Based Evaluation Technique (MACBETH) Multi-Attribute Global Inference of Quality (MAGIQ) Multi-attribute utility theory (MAUT) Multi-attribute value theory (MAVT) New Approach to Appraisal (NATA) Nonstructural Fuzzy Decision Support System (NSFDSS) Potentially All Pairwise RanKings of all possible Alternatives (PAPRIKA) PROMETHEE (Outranking) Stochastic Multicriteria Acceptability Analysis (SMAA) Superiority and inferiority ranking method (SIR method) Technique for the Order of Prioritisation by Similarity to Ideal Solution (TOPSIS) Value analysis (VA) Value engineering (VE) VIKOR method Fuzzy VIKOR method Weighted product model (WPM) Weighted sum model (WSM) Rembrandt method Wikipedia is still the easiest source. Try Google for more.
  21. I am planning for a study to use UAV and CIR images for mapping the beetle infested trees in the forests of British Columbia, Canada. Does anybody have any experience regarding what cameras should I use for this purpose. I am aiming to be able to capture images at the range of 500 to 1000 nm wave length. Thanks in advance

    Hossam

  22. salam kenal semuanya, ijin gabung suhu lurker Teknik lingkungan upnyk 2011
  23. welcome back
  24. An old user coming back
  25. hi I want to know all multi criteria decision making methods(like AHP, Fuzzy set, ANP and etc) which presented until now. please can who list all of them to me and introduce me to a source about each one If possible? or a good book, review article in this subject.
  26. Earlier
  27. thanks every one gislover
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