Logistics refers to the actual process of planning, executing and controlling raw materials or final products from the place of origin to the place of use. Logistics services specifically include order management, transportation, warehousing, loading and unloading, distribution, customs declaration, return processing, information service and proliferation business. Obviously, the choice of goods transportation path and warehouse address involves how to deal with a large number of spatial data and attribute data to shorten logistics time and reduce costs. Geographic information system (hereinafter referred to as GIS) not only has the functions of collecting, inputting, editing, storing, managing, analyzing, querying, outputting and displaying spatial data, but also provides scientific basis for system users to predict, monitor, plan, manage and make decisions. It can be seen that the application of GIS in logistics distribution system can greatly strengthen the overall control and management of logistics process and realize efficient and high-quality logistics distribution service. This paper will discuss the application of GIS in logistics distribution in the following parts.

2 the integration of modern logistics and GIS

1) development of geographic information system

Geographic information system (GIS) is a new frontier science which integrates computer science, geography, information science and other disciplines, and can be used as a basic platform in various fields. This integration is the application, integration and cross-infiltration of various processing processes of information, and it is the process of realizing the digitalization of various information.

In GIS, spatial information and attribute information are inseparable whole, they describe two sides of geographical entities respectively, and are organized with geographical entities as the main line. Spatial information also includes the geometric relationship between spatial elements, which enables GIS to support spatial query and spatial analysis that ordinary management information systems cannot support, thus facilitating planning and decision-making. Now the rise of WebGIS makes it used as a tool for information query and information analysis in more and more commercial fields [3], and GIS technology itself has been integrated into the general models of these commercial fields (such as the network analysis module of ARC/INFO), so the application of GIS technology in various commercial fields has been developing in depth and breadth. In fact, GIS technology can be applied to all areas involving geographical distribution.

2) the development of logistics

With the development of economic globalization, logistics is developing rapidly in the direction of modernization. Logistics modernization not only means logistics means (logistics facilities, equipment, etc. ) and logistics technology have reached or approached the advanced level in the world, and it also refers to scientific logistics management (including logistics organization, logistics planning, logistics transportation scheme selection, economic index determination, etc. ) [4].

As an advanced organization and management technology, modern logistics has been regarded as an important "third profit source" for enterprises besides reducing material consumption and improving labor productivity [5]. It can reduce circulation cost, shorten circulation time, integrate enterprise value chain, extend enterprise control ability, accelerate enterprise capital turnover and create new profits for enterprises.

Especially in the e-commerce environment, suppliers must comprehensively, accurately and dynamically grasp the product flow direction scattered in various transit warehouses, dealers, retailers and various transportation links throughout the country, and make production and sales plans accordingly, and adjust market strategies in time. Therefore, the development of e-commerce has further promoted the rapid rise of modern logistics industry.

Then, if GIS technology is integrated into the process of logistics distribution, it will be easier to deal with the transportation, warehousing, loading and unloading, distribution and other links in logistics distribution (as shown in figure 1), and the problems involved in transportation route selection, warehouse location, warehouse capacity setting, reasonable loading and unloading strategy, transportation vehicle scheduling, distribution route selection and so on will be effectively managed and analyzed, thus meeting the requirements of modern logistics. In fact, with the development of e-commerce, logistics and GIS itself, GIS technology will become an indispensable part of the whole logistics management.

Figure 1 Logistics Distribution Process

Design of Logistics Distribution System Based on GIS

3. 1 demand analysis

Taking the logistics and distribution process of a city as an example, the demand of logistics and distribution system based on GIS mainly focuses on the following aspects:

1), and determine the customer's geographical location and vehicle route through the detailed address string provided by the customer;

2) Reasonable editing of vehicle routes (such as creation, deletion and modification) and customer delivery sequencing can be realized through GIS-based query and map representation;

3) Use specific map symbols to represent the geographical location of customers on the map, as well as different types of customers (such as ordinary customers and member customers, corporate customers and individual customers, etc. ) represented by different symbols;

4) Display the attribute information of the customer symbol through the query function of GIS or click on the map customer symbol, and you can edit the attribute;

5) Query the customer's location and surrounding environment on the map to find potential customers;

6) calling GIS through the business system to display the numerical information of various related operation results of the business system in a graphical way;

7) Based on the comprehensive evaluation model and GIS query, the distribution area can be split and merged;

3.2 the overall structure of the system

A logistics distribution system based on GIS is designed. The system adopts object-oriented spatial data model and spatial database based on relational database to realize seamless data integration. Spatial data index adopts spatial data index structure based on improved R-tree, and attribute data index adopts B+ tree data structure. Network data transmission adopts a three-layer structure model, which is developed by Java Applet. It has platform independence and good security, making it possible to store, analyze and enjoy massive spatial data. The system network structure diagram is as follows:

Fig. 2 System network structure diagram

3.3 System model design

From the above analysis, the logistics distribution system based on GIS should integrate the following main models: facility positioning model, vehicle routing model, distribution area division model, distribution set model and customer distribution sequencing model.

1) facility location model. Used to determine the location of one or more facilities. In the logistics system, the warehouse and the transportation route * * * together constitute the logistics network, and the warehouse is at the node of the network, which determines the route. How to set up multiple warehouses in a given area, the location of each warehouse, the scale of each warehouse and the logistics relationship between warehouses can be easily solved by using this model.

2) Vehicle path model. It is used to solve the problem of how to reduce the logistics operation cost and ensure the service quality in the transportation of goods with one starting point and multiple destinations.

3) Network logistics mode. It is used to solve the problem of finding the most effective distribution route, that is, the layout of logistics outlets. If the goods are transported from N warehouses to M stores, and each store has a fixed demand, then it is necessary to determine which warehouse to pick up the goods and send them to that store, with the lowest transportation cost. It also includes deciding how many cars to use, the route of each car, etc.

4) Distribution area division model. According to the similarity of each element, all or part of the elements on the same layer are divided into several groups to solve the problem of determining the scope of service and sales market. If a company wants to set up X distribution points, it is required that these distribution points should cover a certain area, and the number of customers in each distribution point should be roughly equal.

5) Spatial query model. For example, you can query the number of distribution points within a certain radius centered on a commercial network, so as to judge which distribution center is the nearest and prepare for arranging distribution.

4 system function realization

Then, the logistics distribution system based on GIS can realize the following main functions:

1) Vehicle and cargo tracking: Using GPS and electronic map, the actual position of vehicles or cargo can be displayed in real time, the status of vehicles and cargo can be inquired, and reasonable scheduling and management can be carried out.

2) Provide traffic route planning and navigation.

Plan the traffic route, so that the display can show the designed route on the electronic map, and at the same time show the running path and method of the car.

3) Information query

Inquire about major buildings, transport vehicles, customers, etc. Within the scope of delivery. Query data can be displayed in the form of words, languages and images, and its location can be displayed on the electronic map.

4) Simulation and decision-making

For example, we can use long-term customer, vehicle, order and geographic data to build a model, simulate the layout of logistics network, and establish a decision support system to provide more effective and intuitive decision-making basis.

5 concluding remarks

Nowadays, with the re-emergence of e-commerce and the development of economic globalization, the logistics industry has increasingly become a hot spot [6]. Although it is still in its infancy, it is undoubtedly a useful attempt to establish a logistics distribution system based on GIS, which can efficiently process spatial and attribute data and will surely be the future development trend.

Take the exam and contribute.

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2. Some Problems in the Development of Modern Logistics in China "Scientific Management of Railway Materials" 200 1. 1 p2.

3. Qu et al. Application of network geographic information system in earthquake research. Journal of Seismology 2002. 1p9 1.

4. Ye Jiegang's Theoretical Exploration on Logistics Issues Contemporary Economic Science 2001.1P 51~ 56;

5. Chen Hanlin Computer Weekly "Information Technology Makes Logistics Goods Smooth" 200 1.37, p14;

6. Lan and Shen Jiahong's Analysis of Circulation Problems under E-commerce. China Circulation Economy 2001.1p10 ~1/