GIS is a technology-guided multi-technology intersecting information space science, a computer system that collects, stores, processes and reproduces geographic information data (including graphical and non-graphical data, geometric data and attribute data) , which and can answer a series of questions. therefore, it must be technology-oriented. GIS constantly equips and develops itself with new technologies and methods,which pays attention to data acquisition, data modeling, accuracy of data and reliability of system answers to questions, data volume, data access and confidentiality, data analysis, user interface, cost and benefit, life span of GIS system and organization of GIS system work. These technical problems will be improved with the continuous progress of related disciplines, software and hardware means. At the same time, GIS is an application-oriented information industry, that is, GIS is also application-oriented, besides its basic and public welfare characteristics, serving scientific research and benefiting mankind, which also has a broad market of practical application and value creation. The application of GIS can penetrate into various fields and institutions, forming such as resource GIS, disaster monitoring and prevention GIS, agriculture, forestry, animal husbandry and fishery GIS, etc. The continuous development of GIS depends not only on the basic disciplines of geography, statistics and surveying, but also on the progress and achievements of computer software technology, aerospace technology, remote sensing technology and artificial intelligence and expert system technology. It is located at the edge of Geoscience and technological science, but it is essentially an integral part of information science.
With the development and perfection of GIS theory and the increase of people’s demand for spatial information, in order to make the sustainable development of GIS system, it is necessary to make GIS develop towards integration and intellectualization, which includes the following aspects:
Combination of graphics data and attribute data: at first, graphics and attribute data are completely separated; then, they are connected through internal connection; thirdly, they are mixed; finally, they are completely combined. The requirement of future GIS is to integrate them completely.
Combination of GIS and RS: Remote sensing is an important data source and data update means of GIS. On the contrary, GIS is the auxiliary information of data processing in remote sensing, which is used for automatic extraction of semantic and non-semantic information. Possible ways of combining GIS and RS include: separate but parallel integration (different user interfaces, different tool libraries and different databases), surface seamless integration (the same user interface, different tool libraries and different databases) and overall integration (the same user interface, tool libraries and databases). What the future requires is a holistic combination.
The combination of GIS and GPS and CCD technology: GPS is a global positioning system, the three-dimensional coordinates of any point on the ground can be measured directly with GPS receiver. The combination of GPS and GIS can realize electronic navigation for traffic management, public security detection, automatic navigation, and real-time updating of GIS. If combined with real-time CCD camera and image processing, real-time GIS operation system can be formed for automatic monitoring and management of highway and railway line conditions, as well as operational command system.
The combination of GIS and Expert System: Because GIS is a spatial information system based on geographic data, it must have the function of automatically collecting and processing data, and be able to intelligently analyze and use data, provide scientific decision-making consultation, and answer all kinds of complex questions that users may ask. From this point of view, GIS and ES are combined to form an intelligent and highly integrated GIS system.
Based on the above analysis, in order to get an ideal GIS system, the following main problems need to be solved theoretically by GIS:
1) Methodological issues in GIS design and implementation
Due to the lack of strict engineering management and good analysis and design method support, the reliability and maintainability of GIS software system is poor. This is a problem that people have been trying to solve for a long time, but it has not yet been solved.
2) GIS functional issues
At present, GIS, which is mainly composed of data acquisition, storage, management and query and retrieval functions, can not fully meet the requirements of social and regional sustainable development in spatial analysis, prediction, decision support and other aspects, directly affecting the application efficiency and vitality of GIS.
3) Problems with the management and operation of multimedia GIS
In a hybrid system where multiple data types coexist, how to realize the random operation and effective management of various types of data is a prominent problem in the new era of information media diversification, which is more complicated than the operation and management of a single map database.
4) Deep processing of GIS geographic information
The current GIS is far from playing its role in providing conclusive thematic maps and datasets, which involves the deep processing of GIS geographic information. The result of this deep processing can be a conclusive thematic map or a concluding thematic data set. Both forms are necessary, the former provides conclusive graphical information, the latter provides conclusive digital information, and the deep-processed conclusive results are more direct and beneficial to the user.
5) Spatial information visualization technology and virtual reality technology (VR)
Visualization technology has far surpassed the traditional level of symbolization and visual variable representation, and has entered the stage of exploring visual effects and improving visual tools functions under dynamic, spatiotemporal transformation, multi-dimensional interactive map conditions, and its focus is It is necessary to present the environment and things that are often difficult to imagine and approach in a dynamic and intuitive way. The research on GIS visualization mainly focuses on the following aspects: using animation technology to make dynamic maps, which can be used for visual analysis of phenomena or concepts involving time and space changes; simulate the terrain environment with VR technology, and truly reproduce the landscape for interactive observation and analysis to improve the cognitive effect on the terrain environment; check the uncertainty and reliability of spatial data, visualize abstract data with graphic display technology, and discover the law; graphic design and interactive means for map design and editing, visual map design (such as map color visual design); visualization technology for visual perception and spatial cognitive theory research.
In recent years, GIS technology has developed rapidly, and its main driving force comes from the increasing demands placed on GIS in an increasingly wide range of applications. On the other hand, the rapid development of computer science provides advanced tools and tools for GIS, many new technologies in the computer field, such as object-oriented technology, 3D technology, image processing and artificial intelligence technology, can be directly applied to GIS. in. The following is a brief introduction to several hot research areas in current GIS research.
1) Object-oriented technology research in GIS
Object-oriented method provides a way for people to describe the real world directly by computer, the application of object-oriented technology in GIS, that is, object-oriented GIS, has become the development direction of GIS. This is because spatial information is more complex and cumbersome than the one-dimensional information processed by traditional database, object-oriented method provides an intuitive, clear structure and orderly method for describing complex spatial information, so it is highly valued.
Object-oriented GIS has the following advantages over traditional GIS:
All the objects are encapsulated in the form of objects rather than stored in the form of complex relations, so that the organizational structure of the system is good and clear.
Based on the object, the concept of hierarchy is eliminated.
Object-oriented general-special structure and whole-part structure enable GIS to directly define and deal with complex terrain types.
According to the idea of object-oriented Late-binding, users can define their own data types and spatial operation methods on existing abstract data types and spatial operation boxes to enhance the development and extensibility of the system.
Object-oriented user interface based on icon, which is convenient for users to operate and use. Object-oriented GIS also has some problems to be further studied:
The operation of large objects is still limited by hardware conditions.
The independence and granularity of objects;
The problem of object-oriented data structure, which supports dynamic topology and composite object representation, is the unification of vector and raster data.
2) Space Time System
Traditional geographic information systems only consider the spatial characteristics of the features, ignoring their temporal characteristics. In many application fields, such as environmental detection, earthquake rescue, weather forecasting, etc., spatial objects change with time, and this dynamic change law plays an important role in the solution process. In the past, GIS ignores the tense mainly because of the limitations of hardware and software conditions, as well as technical reasons. In recent years, research on the temporal characteristics of GIS has become very active, the so-called “space-time system.” Usually, the time dimension of GIS is divided into processing time dimension and effective time dimension, processing time is also called database time or system time, which refers to the time when processing occurs in GIS; the effective time is also called the event time or actual time, which refers to the time when the event occurs in the actual application field. The spatio-temporal system mainly studies the spatio-temporal model, the representation, storage, operation, query and spatio-temporal analysis of spatio-temporal data. The current popular practice is to extend the existing data model, such as adding time in the tuple of the relational model and introducing the time attribute in the object model. How to solve a series of problems from representation to analysis on the basis of this expansion remains to be further studied.
3) GIMS-Geographic Information Modeling System
The spatial analysis function of general GIS is far from enough for most application problems, because these fields have their own unique special models, at present, most of the general GIS solve this problem by providing secondary development tools and environments, but the main problem of secondary development tools is that it is too difficult for ordinary users. The key to the successful application of GIS in the special field is to support the establishment of a unique spatial analysis model in this field. The research trend of GIMS is: the application of object-oriented technology in GIS, object-oriented technology describes the objective world with object (encapsulation of entity attributes and operations), object class structure (classification and assembly structure), and communication between objects, which provides a structured way to describe complex three-dimensional space; user modeling interface based on icon (Icon). Objects and spatial analysis operations in the process of modeling are presented to users in the form of icons. Users can also customize icons. Users define, select and operate icons to complete the definition and verification of the model. This method is much more convenient and intuitive than macro language such as AML, the integration of GIS with other models and knowledge bases is a very practical problem faced by many application fields, that is, how to couple models and knowledge bases outside of GIS with GIS into an organic whole.
4) Research on 3D Geographic Information System
Three-dimensional GIS is the basic requirement of GIS in many application fields. At present, most of the GIS provides some relatively simple three-dimensional display and operation functions, but there is still a big gap with the true three-dimensional representation and analysis. True three-dimensional GIS must support true three-dimensional vector and raster data model and three-dimensional spatial database based on it, and solve the problem of three-dimensional spatial operation and analysis. The main research directions include: the research of three-dimensional data structure, including the effective storage of data, the representation of data state and the visualization of data; the generation and management of three-dimensional data; the three-dimensional display of geographical data, including the operation of three-dimensional data, surface processing, raster image, holographic image display, hierarchical processing, etc.
With the development of computer and information technology, GIS is changing rapidly. The development of GIS in the next 10 years is summarized in the following aspects.
1) GIS networking
For the development of GIS, computer network technology is an important technology to play a qualitative role. Its development has made many difficult things to accomplish in the past, for example, network technology makes the database geographically distributed. In this way, each database can be locally produced, updated, maintained and managed, and the network makes these Locally distributed databases can be connected to each other for shared use. High-speed data transfer enables fast data transfer between databases. The development of the World Wide Web provides an effective and feasible way for GIS data to be published, published, accessed and queried on a larger scale. The use of web browsers is visually convenient for people who provide and use geographic data. Geographic data can not only search according to geographical location, special content, production organization, use price, etc., but can also directly perform various spatial operations of data on the Internet, and use various models provided by the network to simulate and directly generate new data results, realize the new concept mode of “network is computer” really. Although the development speed of network technology is amazing, there are still some limitations in the application of GIS, mainly as the transmission of geographic data: at present, there are still some limitations on the network transmission of GIS data, since the data of GIS usually has a large capacity, the capability of network broadband is not satisfactory enough in the process of large-scale data transmission in the long-distance distance, which will be the network technology bottleneck in the development of GIS; the development of GIS network software: network technology has brought more potential to the development of GIS technology, but so far, the industry of GIS software has not fully brought these potential into play, many technologies in the field of GIS are still in the stage of research and experiment, and there is still a certain distance to achieve commercialization and practicality. The effective use of network technology in GIS: the development of technology can only have real value when it brings benefits to people, network technology has great potential, but how to use it effectively in the GIS field, fully and properly exert its potential is still a problem that people need to explore.
2) GIS standardization
The next 5-10 years will be the main time for Standardization in the field of GIS. With the development of GIS, it can be used in various fields, people are constantly aware that the necessary standardization of software, hardware, data and other elements can achieve more effective and extensive use of GIS. The standardization of GIS will be carried out at various levels in the international, national, provincial, municipal, county and institutional scope, its contents may include various components of GIS, various operation processes, various data types, software and hardware systems, etc. The true realization of standardization will enable people to share information and resources on the basis of a common understanding.
3) Data commercialization
In Western society, the life cycle of computer hardware equipment is usually 3-5 years, and the life cycle of computer software is generally 7-15 years, the life cycle of geographic data is decades. The development, update and maintenance of geographic data is time-consuming and laborious, which has been counted in the GIS community that the cost ratio of GIS hardware, software and data is 1:10:100, so how to produce and maintain geographic data more effectively will be one of the main challenges facing GIS in the future. One of the main purposes of GIS generation is to better manage and process spatial information, the GIS spatial analysis function actually uses existing data to generate new data, so the data is the operation object of the entire GIS. Without data, there is no information system, if the data problem can be solved, the information system will be meaningful and valuable before it can actually run.
4) System specialization
Currently, GIS software and systems are still independent as a whole. Many software provides comprehensive GIS functionality that can be used in any department that requires GIS, without specific domain limitations; from the perspective of using GIS institutions, many organizations only need some functions in GIS software, at present, GIS software settings require users to purchase the entire software together when purchasing GIS systems. First of all, considering the users of GIS, GIS may not exist as an independent system in the organization, but as a part of the whole management and operation system of the organization, the various functions of GIS will be integrated into a more direct system with the professional field. Secondly, considering the industrial development of GIS, the various functions provided by the current GIS software will be integrated with various professional software systems for common development. The componentization of software is a precursor to this trend, and it also prepares for the specialization of GIS software. In future applications, GIS may exist as an essential part.
5) GIS enterpriseization
The development of GIS networking makes it more effective to communicate, exchange and share various resources among different departments within the organization. Enterprises and organizations can make overall arrangements and plans for the use of GIS in enterprises from a higher level, which is called “Enterprise GIS”. Enterprise-based GIS has higher requirements for technology and management personnel, which requires continuous technical and management training for personnel.
6) GIS globalization
The development of network technology has narrowed the world space and made the relationship between people closer; the development of the world economy is also requiring people to establish a more stable and harmonious environment. In this environment, GIS is increasingly becoming an effective tool to help people understand the natural conditions and social changes in which they live and depend. At present, countries all over the world are actively developing and using GIS, formulating policies on geographic information, and implementing national GIS projects, for example, the World Bank and other international credit organizations require GIS to be used in their projects to assist decision-making. The standardization of GIS will promote its promotion and use in the international arena, the International Standards Organization has specially standardized and implemented geospatial technology from all aspects.
7) GIS popularization
Not only has GIS been more and more valued on the international stage, but it has also changed people’s lives subtly in people’s daily lives. In the past, people needed to use maps to orient, locate, and navigate, and now the maps are already stored in the database; the best route from one location to another is easily accessible using the GIS system; in a new place, you don’t need to find restaurants, hotels, entertainment centers, shopping centers, banks, tourist attractions, etc. GIS is the best guide.