The identification of the real-world geographic location of an object

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22
votes
3answers
8k views

Best GIS system for high performance web application - PostGIS vs MongoDB

I am working on a web/mobile application based on location data. Since i am already familiar with MongoDB, i found the geospatial indexing of mongo is quite suitable for my needs. As i am mainly ...
19
votes
1answer
4k views

Trilateration algorithm for n amount of points

I need to find algorithm that can calculate centroid A (aka gravity center, geometric center, center of mass) from the figure where circles T1,T2,T3,T4,T5,..,Tn intersect AND length of line R from ...
15
votes
9answers
3k views

How can I determine the location of a visitor to my website?

If I want to provide a website with location appropriate content, what ways can I use to find the visitor's rough location using their IP or header information?
14
votes
5answers
10k views

Is a Country/State/City Database available?

I asked this question Stack Overflow but I was informed that I would get a better to this question here because it's not related to programming. I am creating a directory which uses locations to ...
13
votes
6answers
2k views

What algorithm should I use for wifi geolocation?

School Pickup Use Case (update) It might be helpful to go into a more concrete use case instead of the original backyard example below. Local law enforcement has started cracking down on use text ...
12
votes
2answers
415 views

Propose a new location for Watch Tower using Viewshed Analysis

I want to suggest location for new watch tower in a forest area, but i am confused , on what criteria i can propose a best location. If i am taking DEM , slope and distance from existing tower , ...
11
votes
3answers
2k views

Calculating the distance between a point and a virtual line of two lat/lngs

Please refer to the example and corresponding image. I would like to achieve the following: provide two locations (lat/lng), which are shown below as A and B. From this, a virtual line would be drawn ...
11
votes
1answer
576 views

How much sense does it make to average (lat,lon) samples in order to increase 2D accuracy of a GPS location?

Several GPS applications, like this one, or this one, acquire multiple (lat,lon) samples of a given location, assuming that the GPS unit is not moving, and then take an average of the samples in order ...
10
votes
2answers
105 views

Where does one ask “Where is …?”?

On a fairly regular basis at my place of work we get inquiries of the form "where is Lake Potato?" or "where is Poppingstone Creek?" or... The questions come from co-workers, the general public and ...
9
votes
3answers
6k views

How to generate random locations nearby my location?

I am trying to create random locations nearby my location. What i want is to create random latitude/longitude pairs inside a 200 meters circle surrounding my location. This is the formula i came up ...
9
votes
1answer
96 views

How To Understand Geological Directions?

I was reading a "Guide to Some Minerals and Rocks in Indiana," which was published in the 1950s, and in it there were these bewildering directions: "Bluff along Mud Pine Creek 1.5 miles west of ...
8
votes
3answers
1k views

What GPS device do I need for vehicle tracking?

I am a programmer with no connection to Geographic information, except that I work on application which uses google maps. So here is my problem. I need some device, which I will be able to set in a ...
8
votes
4answers
3k views

How does WiFiSLAM work?

Apple recently acquired WifiSlam. How does their technology work? Their website doesn't go into much detail. Allow your smartphone to pinpoint its location (and the location of your friends) ...
8
votes
4answers
507 views

Geolocation database of beaches

Anyone know where or how to obtain a database of worldwide beaches? Required fields are: name latitude longitude coastline aspect (if possible) Alternatively, is there a way to query Google Maps ...
7
votes
11answers
2k views

Logging GPS and Accelerometer Data - Device Suggestion?

I am looking for a device that can track my location (lat,long) and speed all day long. Perhaps, I need GPS and accelerometer data bundled together. What I want to do is to log my daily activities. I ...
7
votes
2answers
229 views

Is there a GIS to locate exact opposite locations on earth?

I was wandering if there was a GIS that offers to locate the exact opposite location of key locations (countries, even cities ?) on earth ?
7
votes
5answers
232 views

What technique is used to acquire client location?

So far I know how to grab the client location to a application or web application by using the users geolocation or GPS location. I remember the possibility of finding the users approximate location ...
6
votes
1answer
95 views

Dividing the world space to geographic sub-space

I am trying to divide the world space to geographic sub-space from "general" to "specific" locations and without using latitude and longitude information. That is, I am trying to think about the world ...
6
votes
1answer
593 views

Open source location allocation modelling

I'm looking for open source tools for location allocation modelling (eg planning public health facilities). Preferably in a GIS environment. I know GRASS somewhat, but v.net.alloc doesn't seem to ...
5
votes
1answer
573 views

Where can I find High Quality Road Network Information

I am carrying out a research on how complex city road networks get and I need to get accurate map information. I started with openstreetmaps however I ran into a couple of issues: some of the dumps ...
4
votes
4answers
2k views

Calculate distance of point from an arc/polyline

Using Postgres/PostGIS, I am trying to query the database for the closest arc to a particular GPS point. Each Arc is made up of two nodes that are GPS points on a map. Is there a way I could query ...
4
votes
3answers
273 views

EPSG geotiff code and crs us48

I am trying to create a geotiff and the software (raster design) is asking for a code that I thought was EPSG code. however while trying to find out what epsg = us48 I noticed that the dialog actually ...
4
votes
1answer
579 views

Probability of iOS/Android device location accuracy

I'm working with Android and iOS apps that report location. Both iOS and Android can derive location from a combination of cell tower triangulation, visible wifi access points, and assisted GPS. The ...
4
votes
0answers
222 views

Translate Orientation from Sensor data to Geo location

I am tracking a device that might loose GPS signal then and there. And when the GPS signal is too low, I should use the accelerometer and Gyroscope sensors data to guess which way they should have ...
3
votes
1answer
184 views

Worldwide places reachable by sea/ocean

I'm looking for a list of all populated places(not just big cities/ports) on the world that reside on sea/ocean. The list should contain the place name, latitude and longitude. Does something like ...
3
votes
1answer
651 views

How to calculate midpoint given north/south latitude and east/west longitude?

First, sorry if this questions sound very simple. I am very new to GIS. Given four values of north/south latitude, east/west longitude how to calculate the center point that is correct for all cases ...
3
votes
2answers
90 views

Where can I find a map with the location of towns and cities in Southern Sudan?

For a project I have some name of towns and cities in the Southern part of Sudan, the region South Kordofan. Many of these towns I can't find on Google Maps, but I need to know their location. ...
3
votes
1answer
101 views

Looking for HowTos or Examples of Presentation Platforms targeting Management/Clients

Any good ideas about using Google Earth to present self contained geospatial data&app to a client or senior management? The broader issue being explored here is that many of our clients are not ...
3
votes
1answer
101 views

Mastering Geo Locators in ArcGIS 10.2

We just moved from 10.0 to 10.2 and woke up to the wonderful news that all our geolocators are broke and need to be recreated. Most were made in 9.3. This is fine, but the locator building process has ...
3
votes
1answer
99 views

Is there a way to get the method how the location was processed?

Experimenting with the W3C Geolocation API. Is there a way to get the method how the location was processed? I mean GPS, IP, Cell IDs etc. I didn't find any object properties doing that. Thanks!
2
votes
3answers
373 views

GPS and GIS for real time monitoring of an object

How is it possible to store coordinate of object in server in real time using feasible hardware ( can be used by student) GPS into database and retrived in real time?? What are the names of ...
2
votes
1answer
252 views

Why does Updating Location of ArcSDE Feature using ArcObjects .NET give Error HRESULT E_FAIL has been returned from call to COM component?

I have been able to connect to an Enterprise GeoDatabase, retrieve features from it and update attributes. However I am having problems accessing and then updating the shape property of a feature. ...
2
votes
1answer
379 views

Openstreetmap - retrieve nearby big cities for a given location

I was wondering how I can retrieve places near a given location? For example, if I pass the osm API the location "Paris" is it possible to retrieve all the main biggest cities around Paris within a ...
2
votes
2answers
672 views

Reading MODIS L1B into ENVI

I am working with MODIS Terra (and simultaneous ASTER) Level 1B swath data using ENVI and am having one of these "this should be easy" questions about the most direct way to get to geo-referenced ...
2
votes
0answers
119 views

Geolocate stores inside a mall?

OpenStreetMap lists the malls in Albuquerque, but not the stores inside these malls. Using the in-mall map/directory, wouldn't it be easy to add stores inside the mall? Is anyone doing this? ...
1
vote
4answers
340 views

Offline Python or C++ library for plotting locations on map?

I'd like to plot locations using longitude and latitude coordinates using Python or C++, is there a good library for such a task? I know that matplotlib is an option, I'm wondering if there are any ...
1
vote
1answer
733 views

add a feature in openlayers using lonlat from geolocation

I'm trying to add a feature in a openlayer's vector layer using the lonlat that came from the HTML5's geolocation API. Combining tutorials for the geolocation and this demo I created the following ...
1
vote
1answer
209 views

What is the best database for an online Android location app?

I am working on Android app for locating food places in my city. Using Google Map v2 api. App shows user his current location, and the closest food spots around him. I want to store location ...
1
vote
1answer
196 views

Android GPS: average location resolution time

What is the average location resolution time on a SmartPhone(Android) GPS? Assumptions : The user is under the open sky.
1
vote
1answer
74 views

How to convert distance into latitude + longitude [duplicate]

I have start point (latitude) I know direction, lets say strictly north, and I want to calculate latitude which is 100 meters above the start point. The same for longitude. I believe there should be ...
1
vote
2answers
308 views

Geo IP database for Brazil?

I am looking for a database that offers good accuracy for obtaining region from an IP address? Or, if this question is too fuzzy: Which one is (possibly) the most accurate? Note: I only need a ...
1
vote
1answer
149 views

I would like to show points moving on a map by date

I would like to create a map where i can see points moving. I have table of points for example with a date column, A 01/01/2012 B 02/01/2012 C 03/01/2012 D 04/01/2012 E 05/01/2012 F 06/01/2012 I ...
1
vote
0answers
9 views

Locating Wlan accesspoints-how? [closed]

Having a Netbook I would like to map routers geographically-how? Starting from scratch. Thanks a lot for your suggestions!
1
vote
1answer
59 views

What sub-meter geolocation solutions exist and how can I integrate them into a web and mobile mapping workflow?

I am the manager of seven water systems. What I am trying to do is map out every meter and valve on to a map and then my workers can have the maps on their iPhones so when they have to go fix a water ...
1
vote
0answers
57 views

Which geo-location available in Twitter data should I use?

I am extracting twitter location on my side.Few tweets has perfect location but in most cases additional details are available (i.e. Country,bounding_box,poly lines etc) So confused regarding ...
1
vote
0answers
184 views

How to add Points to a jvectormap in Miller Projection [closed]

On jvectormap you can pull down a map of map of austria. I want to be able to plot points (using WGS84 coordinates) onto that map. The map has this information inside: "projection": {"type": ...
1
vote
0answers
50 views

Best Source for Consumer Data for direct contact [closed]

Parcel data is fairly easy to consume within a map; it gives you name and address information. Are there any map based contact information providers? Does anyone provide a service that is consumable ...
0
votes
2answers
205 views

Socket Server to receive GPS location data

I am working on a web application which receives data sent from trackers via TCP Packets containing location information. Up until this point we have been working with dummy data within the mysql ...
0
votes
2answers
237 views

Spatial databases in location based search

I'm developing a location based application in which i was in the plan of dividing the globe into grids and when the client requests information, will create a table or similar data model which will ...
0
votes
2answers
71 views

Definite way to confirm a geocode as correct

So you tested few geocoding services for the same street address. You got results varying by 0.7 to 3 kilometers. How can you tell which geocoding service was more right, other than letting your user ...