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Hello, I am considering to by a LIDAR + drone for vegetation studies. I am not an expert in active remote senisng/LIDAR sensors, but I do optical remote sensing.
I had a look to the DJI Matrice 300 with the Zemuse L1 LIDAR, but I cannot find any information regarding the number of points per square metre. I asked the supplier for my country, but he could not asnswer either.
Does anyone know this information, or any other dron portable lidar sensor suitable for forestry/agriculture studies?
Thanks
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the points per sqm is a function of flight elevation above and will also be affected by the attitude of the drone. Specific to the question you asked, look at
they state Over 30 minutes, at a speed of 10m/s, a flight altitude of 100 m, with a side overlap rate of 20%, point cloud density > 200 points/m2.
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Right now I am studying GRAVSOFT for geoid modeling to use it in my thesis, I tried to read the manual but it was not explaining the GUI Python version (it is explaining the Fortran version), so that I am still confused to understand the software clearly. I would like to understand clearly which data I have to use for determination geoid modeling and the steps (step by step) of doing that using GRAVSOFT programs.
please provide me any documents or any files that can let me understand all the programs inside the GRAVSOFT interface specifically for creating geoid modeling.
Thanks in advance and your comments are appreciated
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Anas Sharafeldin Mohamed Osman GEOCOL and GEOGRID for gross-error detection.
Good luck
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Given the two following patterns: the left or the right, which one is more beautiful than another?
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Left.
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What is space? Is it what is conceived by Newton or by Leibniz? Both Newtonian and Leibnizian views of space are framed under the mechanistic thinking of Descartes back to the 17th century. Christopher Alexander in his life's work - The Nature of Order conceived and developed a brilliant new view of space: space is neither lifeless nor neutral, but a living structure capable of being more living or less living. This new view of space has some far-reaching implications. It implies that we make space or our built environment better, smarter, or more sustainable, or more livable, or more resilient. More importantly, it implies that goodness of space is a matter of fact rather than an opinion. In this paper, we attempted to provide empirical evidence space indeed has different degree of beauty or life:
By asking this question, what I really wanted to know how long it will take for us to adopt Alexandrine view of space. Benoit Mandelbrot said Euclidean shapes are cold and dry, but nature, traditional buildings and artifacts are full of living structures, as noted by Christopher Alexander.
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As an architect it's the biggest question
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Do you have this geotechnical program?
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Try to contact the Kansas Geological Survey.
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I'm looking for some case studies (preferably newer ones) using Geomatics Engineering ( GIS is more favorable) in sustainable development. I'll be thankful if anybody can help me with some e-books, articles etc.
Regards,
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We are pleased to invite You to the third conference in Geodesy, Geomatics and Engineering, which will take place at Gdańsk University of Technology, Poland, on the 22-25 of June 2017. Our mission is to provide a highly acclaimed conference forum for researchers to contribute their research results.
BGC is organized by the Gdańsk University of Technology, Faculty of Civil & Environmental Engineering and the University of Warmia and Mazury in Olsztyn, Faculty of Geodesy, Geospatial & Civil Engineering and Poland (Gdansk) Section C Chapter IEEE.
The conference proceedings of the 2016 BALTIC GEODETIC CONGRESS (BGC GEOMATICS) are indexed in Web of Science: webofknowledge.com
BGC ORGANIZING COMMITTEE
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Congratulations on your BGC 2017 Congress. I will certainly follow your updates.
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Hello,
Just for contextualization my research is about an inter-row plantation guidance for precision agricultural application. The approach chosen goes throw the use of 2D point-cloud information from a LIDAR laser scanner and its posterior processing and filtering. The final result is a reference centered between the two row plantation, which will be used in the control algorithm. 
Lately, I am searching for related works, because I want to know the state of the art on the subject of interest, nevertheless I am not finding anything relevant. What I mean with anything relevant, is that all works found are about row crop guidance for small plants like, for example, soy crop, but my work is focused in bigger plants, like coffee, olive or citrus tree. 
From this I restate my question: How is the state of the art on inter-row plantation guidance for plants like trees cultivars? Any reference will be of great help.
Thanks
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Hi! I suggest you to take a look at this paper: "A tracked mobile robotic lab for monitoring the plants volume and health". 
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Least square adjusment programme
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Hi, 
you could try out also goGPS: http://www.gogps-project.org/
We have been developing it since 2007, and it includes several positioning strategies, including epoch-by-epoch least squares adjustment and Kalman filtered solutions.
There is a more complete (but more "research-oriented") version in MATLAB and a version with less options (but more apt to be used in production) in Java.
We can provide support (as time allows!) through support@gogps-project.org and/or GitHub issues system (https://github.com/goGPS-Project/goGPS_MATLAB/issues?utf8=%E2%9C%93&q=is%3Aissue%20is%3Aclosed%20).
Feel free to contact me if you have any question!
Eugenio
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The ground tracks of a single satellite cross each other after a certain time. At the intersection of two ground tracks (called crossover) the altimeter system allows to observe the sea surface twice. If the sea surface would not change, the sea surface heights derived from measurements of both ground tracks should be identical. In reality, the difference of sea surface heights (the so called crossover differences) do not vanish due to errors of the orbital height
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Hi Doha,
the main contributions to crossover differences used to be orbit errors. For Geosat and the ERS-satellites crossover adjustment/crossover height minimization was used to constrain the orbit solutions. However, not only the orbit errors are minimized but also long-wavelength sea level signals.  Nowadays, with much more tracking data, greatly improved gravity field models and better dynamical modelling it is not used any further.   A commonly used alternative method is to adjust the ERS/Envisat data to Topex/Jason data. If you use ERS (and Envisat) data you might want to check  whether  crossover adjustment (or something else) has been used for the specific orbit model.
Hope that helps, Saskia
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I have the data containing the GPS coordinates of the vessel across the Bay of Fundy and need to use the latitude and longitude to estimate the tidal heights at those points. I also need to plot these heights at the recorded time intervals.
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This could be done in GIS such as ARCMAP.  The tidal heights per time of day and location are well known or could be computed.  Then once you compute the tidal heights for each location by time, you just select the times the vessel is at each location and that could be plotted or mapped in various ways in ARCMAP.
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Does anyone know how to find shape factor of a semicircle section.
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Dear Motwani
Do you mean is 'shape functions' in the numerical models?
best regards
Panji
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I'm researching methods to transport horizontal and vertical coordinates of the surface plan for underground, in engineering works (tunnels). I know the methods of Weissbach, bobs (wires, optic and laser) and use of deTaylor-Hobson spheres, is there any additional methods? And what about recommendations? Thanks in advance.
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RTK-GPS and Total station, yes. Find the attached file for more details.
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We have an Infragram Point & Shoot camera (a modified Mobius Action Camera whose low-pass filter was replaced by a red filter; http://publiclab.org/wiki/infragram-point-shoot). For this modified camera, the "B" channel should be NIR. So, the "R" channel should be "red+NIR" and the "G" channel should be "green+NIR". We took a photo of leaves together with a Labsphere white panel. From the DN values of the three channels, how to calculate the reflectance values of NIR, red and green regions, respectively? How to calculate NDVI from the photo? Many thanks!
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Thanks a lot for your answer!
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Is there a program converted the EGM96 spherical harmonic coefficient set to their ellipsoidal harmonic coefficient counterpart?
I'm looking for a program to converted spherical harmonic coefficient (EGM96 or EGM2008) set to their ellipsoidal harmonic coefficient .
To develop this synthetic set of coefficients
Or how to get ellipsoidal harmonic coefficient of any EGM
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Dear Abdel
Please access to this link to get more information about EGM96 and EGM2008 http://earth-info.nga.mil/GandG/wgs84/gravitymod/index.html
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I have been trying to search for topography (DEM) data, came across the GTOPO30 data set, and the website https://lta.cr.usgs.gov/
but still I am unable to get the data-set.
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Thank you all I now have the data
For indian domain (-10 S to +40N and 60E TO 100 E)
the file name is E060N40.dem
Now trying to find a way to read binary data.
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Levelling, misclosure, total length.
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You may approach the accuracy issue as a leveling network adjustment problem using least squares solution. Then you will end up with several statistical parameters to qualify your results such as the variance component and the residual per each estimated point in your leveling network.
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I am looking for the best way to extract information on settlement areas using only Landsat 8.
I have read that NDBI is not as accurate because of some noise from vegetation and soil. The IBI technique also seems rather long.
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Around 1991, Les. Worral has informed us that "more than 80% of data used by
managers and decision makers is related geographically". Back then, at the very early days of world wide web (WWW), with the absence of smartphones and Location Based Services (LBS) such news signified the important contribution of geograpfical thinking and relationships of data used by decision and policy makers. Today, after 23 years of major advances of internet with cloud computing and using real-time web-gis servers and geospatial modules, with availability of qualitative Open-Source software and web-services, is it possible to estimate the geographical relation of data used by managers and decision makers at a global scale? Is there existant such a research approach?
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Again it is a good research question. Although, it may be difficult to quantify the exact percentage of data being used by managers and decision makers that it is related geographically today without empirical studies. Please see this report.
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Where do you classify engineering surveying, for instance?
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I think Photogrammetry is a very important branch, especially taking into account developments within Unmanned Aerial Systems (UAS). In my view, image measurements will be a very important part of future surveying profession.
Another important branch is laser scanning.