Monday, May 28, 2012

3D Ground-Water Flow Modeling Based on GIS




3D Ground-Water Flow Modeling Based on GIS




The geographical information system (GIS) has provided effective tools to capture, store, manage, analyze, and express spatial information. Gradually, the research region has included the dynamical mechanism and the spatial-time characteristics of the geography process, transmission mechanisms, uncertainty (multi-solutions), predictability, and so on. Correspondingly, GIS modeling is one of the hotspots of current GIS research. The paper is the embodiment of GIS modeling methods applied to geo-simulation research. Also, it provides the model support for the management of groundwater resources. In this paper, the methods for constructing the ground-water conceptual model through a 3D stratum model are discussed. Firstly, the constructing method of Delaunay triangulation with constraint conditions is proposed, which is suitable to the ground-water flow simulation. Then stratum (or aquifer) multi-DEMs are completed. Based on the multi-DEMs, the Su-Xi-Chan hydrogeological conceptual model is reconstructed by irregular Tri-prism. In order to prevent dispersed irregular tri-prism voxels from disunity, the spatial index mechanism is established for the groundwater model. 


Finally, the 3D groundwater simulation model is integrated with GIS, which can provide data for 3D numerical simulation. The results indicate that the integration of 3D GIS and geo-analysis model is convenient and can accelerate the process simulation of geoscience.


Sunday, May 20, 2012

Applied Geographical Information System (GIS)


GIS application "The importance of system architecture design"

Business requirements include, but are a variety of business workflow and Web services for managing a business. There needs to be clarified at an early stage of the planning process of these workflows and services. Workflow and service made it clear here is the foundation of the subsequent steps of the planning process. Estimated the amount of processing at the peak of workflow and business services, design load of the system (server processing time, network traffic, etc.) must be predicted on the basis of it. Load caused by processing of these will be basic information for the network infrastructure required to determine the appropriate specifications and hardware requirements (performance requirements and processing power). Develop a project to introduce to procure the necessary technology. In this project in addition to budget and schedule to determine the various interim targets to complete the project. When you begin the design work and implementation work, you must have prior approval. At that time, as a result of an investment (budget), and then decide whether to approve based on whether the benefits brought about and how the business funds (schedule) a predetermined period of time. Can plan appropriate, the introduction of system risk is reduced. To ensure a successful project, you do not will have to build a system that meets the business requirements were investigated. By setting a goal for the intermediate to clarify the indicators of system performance, the performance goes up in stages, concrete verification plan, You can certainly reduce the risk of introduction. Plan is a gradual process tailored to the rapidly changing technology. To actually plan, you need to consider the evolution of technology and changing business needs. In addition, you must to be carried out to ensure that project tasks on schedule and within budget provided an effective change management process is responsive, was decided.
Distributed computing environment, must be designed to meet the requirements (productivity) performance of the user. Most inferior performance by the "weakness", the performance of the entire system would be constrained in the system. Thus it is important it is, in accordance with the system architecture design process is to determine the balanced hardware solutions. Is to procure equipment and network hardware load balancing system based on the model, you can achieve maximum system performance at minimal cost.

Conditions for building a high-performance GIS is not just hardware. You need to design a business workflow to optimize the productivity of the client (simple maps), that can efficiently manage large spatial processing of the load. In addition, designing a geo-database to meet the performance requirements and usability of the system to the authenticator, and then select a data source. In addition, the operational components of the platform (servers, workstations, storage) when you select, you will need to secure the performance can be processed in a reasonable service response time of peak load by the business workflow. In addition, it is also important to design a system architecture taking into account the limitations of distributed communication network bandwidth requirements and overall performance. In other words, you must select the solution architecture and technology infrastructure, such as a shared resource can be saved. System architecture design is the foundation for building a highly productive environment.

The best way to promote a smooth introduction to understand the technology first, to quantify the user requirements, on it, is to select a software technology that suits the purpose, to deploy the appropriate hardware. If you ignore the initial step, after all, it does not have to fix it later; you will need a tremendous cost. Cost of change will increase more rapidly as can be seen from Figure right, the introduction of advance.

Saturday, May 19, 2012

Why need GIS for System Design


Why need GIS for System Design and Architecture

The purpose of this document is to share how to design a system for rapid deployment of appropriate and (GIS) Geographic Information Systems technology. How to design this system, which consists of guidelines for the provision of the necessary hardware specific business requirements, the selection of the best software, the use of a data source that is configured properly, and to improve user productivity. This document will focus on the (GIS to function without problems even when the peak load during operation) performance and scalability of the system. Topic is also an important feature and software (GIS needs of the user) analysis of business requirements, we are not deeply touched. In "Thinking about GIS" Thinking about GIS book by Dr. Roger Tomlinson, known as the father of GIS, GIS framework of a comprehensive plan has proven already been introduced. To design the system architecture, you will need to identify the software for GIS information to clarify the necessary information to generate their results.

System architecture design is the process was invented by Esri work for a successful operation in the enterprise GIS. In this process, with an understanding of information technology existing, and proposes a concrete hardware and network solutions based on the needs and expected (user) the current business needs. To determine the optimal hardware solutions, all application requirements, data sources, human resources, these will be an important element (see Figure). Experience from the initial implementation of GIS, the importance of understanding the relationship between the load requirements and can be recognized. In other words, from the user's workflow business requirements, the need for deriving the load on the infrastructure of the underlying hardware and network will be recognized. Among them, investigate the business needs of the GIS, on made it clear (architectural patterns of applications and data) Workflow general business, establishing a process to determine the technology solution for production GIS according to the method of system architectural design will be.