The GIS GateWay

HTTP stands for Hypertext Transfer Protocol . It's a stateless, application ­layer protocol for communicating between distributed systems, and is the foundation of the modern web.  As a web developer/Mapper, we all must have a strong understanding of this protocol. HTTP allows for communication between a variety of hosts and clients and also supports a mixture of network configurations through the internet. it does not keep state between different message exchanges hence making itself a stateless protocol. The communication usually takes place over TCP/IP , but any reliable transport can be used. The default port for TCP/IP is 80, but other ports can also be used. The client sends a request to the server (host) and receives response just on his/her browser. The current version of the protocol is HTTP/1.1, which adds a few extra features to the previous 1.0 version. The most important of these, in my opinion, includes persistent connections, chunked transfer­-coding and fine­-g

WELCOME TO GIS WORLD BUILDING A GIS Application a)Waterfall method  1. Gathering requirements and specifications 2. Designing 3. Implementation 4. Testing 5. Adaptation Requirement analysis and specifications involve interaction among sponsors, users and developers of the software product. The purpose of requirement analysis is to produce a requirement document clearly specifying the agreed upon goals and the functionality of the proposed product as well as the constraint under which it will be operating. Design involves the generation of a design document to serve as a blue print for the proposed system. Developers and adaptors are usually involved in this process. Adaptors are involved in order to help assure that the design is consistent with a graceful evolution of the system. The design document often includes graphical depictions of system struc

GIS datasets formats Typical formats of data sets, which allow you to conveniently work with multiple information or map layers, include spatial and attribute data. Spatial data comes in the forms of raster and vector and is generally organized into so-called layers or thematic maps.   Raster data is digital image composed by rectangular grids or cells that contain numeric information from a defined range to characterize geographic features. Digital Elevation Model (DEM) is a form of raster data important in depicting a terrain. It provides crucial information on the topologies of a geographic span.      Vector or shapefile data is constructed as points, lines, and polygons to represent geographical features.   Attribute data is information used to describe characteristics of a locale . The data is organized in a table containing information linked to a spatial feature by a common identifier. This gives you details or certain types of information associated with each specific fe

WHAT A GIS PROFESSIONAL SHOULD KNOW   Having some competence in programming has become a critical requirement for many geospatial positions. The majority of GIS analyst level positions require some expertise in programming and application development.  So which languages should you learn for GIS programming?  Python is a popular scripting language in the GIS arena, especially for those wanting to work with ESRI desktop products. Learning Python is the way to go for scripting and creating tools inside of the ArcGIS framework.   C# is another recommended programming language that is relatively easy and intuitive to learn.  Learning .NET will also allow you to customize ArcGIS.  Using VBA is on the decline and  beyond ArcGIS 10 For web-based applications development,learn HTML, javascript, and CSS as a baseline.  Java, PHP, and ASP.NET are additional programming languages for more advance web development. Where to get started?  Learning the basic concepts of programm

What is GIS? it is a computer system designed to capture, store, manipulate, analyze, manage, and present all types of spatial or geographical data > data that has location. This is actually a question which everyone who doesn't know about GIS asks themselves. I have came across this quiz severally being asked by my friends. Below is a hierarchy kind of, steps to building your GIS career.   GIS Intern Almost every higher level (Technician, Analyst, etc.) position will require some hand-on job training.  The best way to achieve this is through an internship.  Internships are mostly low-paying, part-time jobs but they are the best way to get further GIS training and to develop your GIS skills in a real world setting.  Learning GIS out of a textbook is a great way to get started, but in reality, few GIS tasks are solved as neatly as the “follow steps 1-10” of your workbook.  Getting an internship has become more competitive in recent years.  To be a competitive can

Universal transverse Mercator In Kenya is the mostly used map projection due to its accuracy in conformality hence preserving the shape of the earth. Global Features of utm i)   20 latitudinal belts of 8 deg in the N-S directions labeled from C at 80 degrees South-72 degrees         South to X at 72 degrees North -84 degrees North .     Kenya in belt M and N (ii)  The  origin  of  longitude  is  the  central  meridian.  The  origin  of  latitude  is  the            equator (iii)  False northing is 0 m N but 10,000,000 m S  for southern hemisphere to avoid the          use of negative figures. (iv)  False easting is 500,000 m for each zone (v)  Scale factor at central meridian is 0.9996 (vi)  Latitude varies from 84 degrees north to 80 degrees south The reference ellipsoid used in Kenya is Arc Datum 1960, the following are features of utm in each Zone in Kenya. Zone 36, Longitude of central meridian 33 degrees East Latitudinal belt, N/M Reference ellipsoid for Kenya is

Remote Sensing is interesting alongside GIS analysis. They both collaborate when it comes to performing some functionalities. I produced my very first Map  from a layer-stacked satellite imagery bands using ERDAS  IMAGIN software for image analysis after which ArcGis desktop ArcMap assisted me in creating the map layout. Its beautiful  though not all features are classified. As some people say Learning is a continuous process, then keep learning new things every day.

Hi all, i read this somewhere and i found it good to share with you, especially my classmates. Hope you'll benefit. DISTORTION PROPERTIES IN MAP PROJECTIONS angles, areas, directions, shapes and distances become distorted when transformed from a curved surface to a plane all these properties cannot be kept undistorted in a single projection usually the distortion in one property will be kept to a minimum while other properties become very distorted 1. TISSOT'S INDICATRIX is a convenient way of showing distortion imagine a tiny circle drawn on the surface of the globe on the distorted map the circle will become an ellipse, squashed or stretched by the projection the size and shape of the Indicatrix will vary from one part of the map to another we use the Indicatrix to display the distorting effects of projections 2. CONFORMAL (ORTHOMORPHIC) a projection is conformal if the angles in the original features are preserved over small areas the shapes of object

MAP PROJECTIONS  A map projection is a systematic transformation of latitudes and longitudes of location on the surface of a sphere or an ellipse into locations on a plane surface. Re-projection- it is the transformation from one coordinate system to another coordinate system. Projecting the globe into a map is very essential for easy storage, retrieval and even transportation from one place to another since it can be folded. Today, I am going to just state the different types of projections being used across the whole world.   TYPES OF MAP PROJECTIONS  1. Planar projections- orthographic                                    -stereographic                                    -gnomonic 2.Conic projections  -Albers Equal area                                   -Lambert conformal conic projection 3.Cylindrical projections-Mercator projection                                         -Transverse Mercator                                          -Universal Transverse Mercator (U