Architecture of GIS

GIS architecture encompasses the overall design and organization of a Geographic Information System (GIS).
The components of GIS architecture include hardware, software, data, people, and methods.
The architecture determines how these components interact and work together to create an efficient GIS system.
There are two main types of GIS architecture: client-server and web-based architecture.
In client-server architecture, GIS software runs on a server and is accessed by users through client computers.
The server is responsible for data storage, processing, and analysis, while the client is responsible for data visualization and user interaction.
Multiple users can work on the same dataset simultaneously, making it ideal for collaborative work.
In web-based architecture, the GIS software is accessed through a web browser, eliminating the need to install software on local machines.
The GIS data and software are stored on a server and accessed through a web interface, making it ideal for remote work and data sharing.
The hardware component of GIS architecture includes computer systems, storage devices, and input/output devices required to run and manage the GIS system.
The GIS software is the core component of the GIS architecture that enables users to capture, manage, analyze, and visualize geographic data.
The data component of GIS architecture includes various types of spatial and non-spatial data required to create and analyze maps.
The people component of GIS architecture includes GIS professionals, stakeholders, and end-users who use and maintain the GIS system.
The methods component of GIS architecture refers to the various techniques, procedures, and tools used to create, manipulate, analyze, and visualize geographic data.
The GIS architecture provides a framework for integrating the hardware, software, data, people, and methods to create a functional and efficient GIS system that meets the needs of the stakeholders.

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Accuracy Assessment

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History of GIS

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Development and scope of Environmental Geography and Recent concepts in environmental Geography

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Supervised Classification

Image Classification in Remote Sensing Image classification in remote sensing involves categorizing pixels in an image into thematic classes to produce a map. This process is essential for land use and land cover mapping, environmental studies, and resource management. The two primary methods for classification are Supervised and Unsupervised Classification . Here's a breakdown of these methods and the key stages of image classification. 1. Types of Classification Supervised Classification In supervised classification, the analyst manually defines classes of interest (known as information classes ), such as "water," "urban," or "vegetation," and identifies training areas —sections of the image that are representative of these classes. Using these training areas, the algorithm learns the spectral characteristics of each class and applies them to classify the entire image. When to Use Supervised Classification: - You have prior knowledge about the c...

Change Detection

Change detection is the process of finding differences on the Earth's surface over time by comparing satellite images of the same area taken on different dates . After supervised classification , two classified maps (e.g., Year-1 and Year-2) are compared to identify land use / land cover changes . Goal To detect where , what , and how much change has occurred To monitor urban growth, deforestation, floods, agriculture, etc. Basic Concept Forest → Forest = No change Forest → Urban = Change detected Key Terminologies Multi-temporal images : Images of the same area at different times Post-classification comparison : Comparing two classified maps Change matrix : Table showing class-to-class change Change / No-change : Whether land cover remains same or different Main Methods Post-classification comparison – Most common and easy Image differencing – Subtract pixel values Image ratioing – Divide pixel values Deep learning methods – Advanced AI-based detection Examples Agricult...

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