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Geographic Information System has made great progress in theory and technology in recent 60 years. The application field of GIS has expanded to all aspects of society, and the social influence is increas‐ able growing. The architecture, development mode and service mode of GIS have undergone profound changes. In order to promote the further development of GISystem, this paper focused on the following three issues based on summarizing the three meanings of “S” in “GIS”, namely “System” “Science” and “Service”, and the fruitful achievements of “GIS” in recent 60 years. The first issue is how to un‐ derstand GISystem. This issue should be analyzed from two aspects, and one is to discuss the connotation of geographic information system through analyzing the three key words (namely system, information and geographic) of GIS. The other one is to analyze the relationship between GIS and map, computer mapping and map database. This paper holds the idea that GIS originates from and goes beyond map, computer map‐ ping and map database. It should be considered that GIS has the characteristics of equipment. The second issue is how does GIS evolve. This issue focuses on the social demand background, technical background and discipline background of the development and evolution from “Geographic Information System” to “Geographic Information Service”. It also focuses on the main manifestations of the development and evo‐ lution of GIS from the aspects of application field, expansion of data resources and functions, architecture, development mode and service mode. The third issue is where will the future development of GIS go. We discussed that the limit application domain expansion of GIS and point out that the future development of GIS must face the urgent needs of national economic construction and national defense construction. Based on the analysis and comparison of three existing GISystem service modes, we consider that the “hybrid” technology system of “grid integration” and “elastic cloud” is the best choice for GISystem service mode. Finally, this paper puts forward six key technical problems that must be solved in the implementation of “hybrid” spatiotemporal big data platform technology based on “grid integration” and “elastic cloud”and designs the application mode of “spatiotemporal big data platform”. [ABSTRACT FROM AUTHOR]

The construction of space⁃based information service system integrating positioning, navigation, timing, remote sensing and communication (PNTRC) will provide a powerful guarantee for cross⁃border realtime communication, global tracking of moving targets, and rapid response to disasters. It also puts forward new requirements for efficient network communications, especially satellite routing planning algorithms. In order to optimize the communication link and reduce the time delay, this paper makes full use of the advantages of direct view between spatial grids and high coding calculation efficiency, and pro⁃ poses a satellite grid space grid computing method. This paper introduces the GeoSOT⁃3D grid subdivision model and applies it to the aerospace, proposes an aerospace grid index big table, and develops a set of satellite visibility analysis and inter⁃satellite routing planning by querying the grid visibility look⁃up table. In order to verify the feasibility and applicability of the proposed algorithm, based on the coding generation principle and visualization of the aerospace grid coordinate test platform, a global grid index big table is established. Three sets of verification work are carried out after simulating the 90/15/2 Walker constellation, including grid big table experiment, inter⁃satellite calculation efficiency experiment, and inter⁃satellite route planning experiment. The experiments verify the feasibility of the inter⁃satellite link calculation and application process in terms of organization, storage, calculation and planning. The efficiency of grid visibility analysis to determine whether the satellite connection grid code is negative is 2.2 times higher than the traditional algorithm, and the efficiency of the visibility analysis based on the pre⁃established universal visibility table is 20.9 times higher than the traditional algorithm. The efficiency of grid ⁃ based inter⁃satellite routing planning is improved by nearly 25 times under the shortest distance constraint, and approximately 20 times under the minimum hop count constraint. Through theoretical analysis and experimental verification, it is initially shown that the algorithm is feasible and efficient. We hope that the proposed algorithm can be used in emergency communications, disaster warning, maritime rescue, etc., and also contribute to the construction of satellite Internet. [ABSTRACT FROM AUTHOR]

[Objective] According to the requirement of climate, soil topography and other environmental factors for the growth and development of red-centered kiwifruit, the index system of regionalization by the soil data, terrain data and meteorological data from 1971 to 2017 at 24 stations around Wangcang county was established to provide a reference for the development layout of Wangcang red-centered kiwifruit industry and fill in the gap of local research. [Method] Based on the GIS technology and the 1.250000 DEM data which were fd to perform grid estimation and spatial analysis on the red-centered kiwifruit regionalization indirom the National Basic Geographic Information Center, a small grid computing model was establishecators, and the planting suitabilities of red-centered kiwifruit in Wangcang county were divided into three regions' unsuitable area, sub-suitable area and suitable area. [Result] The suitable area for red-centered kiwifruit planting covered 208. 53 square kilometers and mainly concentrated in the diagonal line of Mengzi town, Yingcui town and Zhengyuan town in the northeast of Wangcang county, the south Nonjian town, Hualong town in the east side of the east-west trough valley region and other regions; The sub-suitable area for red-centered kiwifruit planting covered 597. 15 square kilometers and mainly concentrated in the southern Wangcang county around the most suitable area. [Conclusion] The three ecological factors of climate, soil and topography were synthetically considered in the paper. The local reality of Wangcang county was fully combined, and the obtained detailed and intuitive results could be showed by adopting the index classification method and provide a valuable reference for the local government, decision-making departments and enterprises to plan and manage the development of red kiwifruit industry. [ABSTRACT FROM AUTHOR]

In order to take full advantage of expanding land use/cover vector data, quickly mine the underlying information of features changes? and further provide the technical support and decisionmaking basis for the scientific management and overall planning of land resource? an accurate approach and efficient tool to compute and generate land use/cover change transfer matrix from multiple attributes or aspects of features are proposed in this paper. Firstly, the formal definition of general transfer matrix (GTM) is given and its basic characteristics and information implications are summarized. Secondly, the main problems and the corresponding solutions during its computation and generation process are discussed, whose four steps, namely data pre-processing, feature matching, change detection and matrix production are also explained in detail. Finally, the visible software tool developed by the integrated secondary development is described briefly. It is concluded that the proposed approach and the related tool can greatly enhance the accuracy and flexibility of GTM vectorized computation and generation, and effectively overcome the shortcomings of manual processing such as low efficiency, long cycle, error-prone and difficult to check, as well as the limilations of the commonly used grid computing methods such as low accuracy, single results and inaccurate and comprehensive reflection of the change and transfer of land use/cover elements in different attributes. [ABSTRACT FROM AUTHOR]

To solve the problem that nodes can easily suffer from various attacks during the process of coverage optimization, this paper discussed reliable coverage technology on the basis of the trust management system framework, and proposed a reliable coverage algorithm based on grid trust value. The algorithm performed the reliability screening and rotation scheduling on nodes, and the coverage based on the credibility of grid point by the way of parallel coverage. After discussing the value of the trust threshold, the paper found that it had a significant influence on the security of whole coverage area and the coverage quality. By comparing the new algorithm with traditional single coverage algorithms, the algorithm can improve the security and network lifetime effectively. Simulation experiments show the effectiveness of this algorithm and reflect the correctness of the analysis. [ABSTRACT FROM AUTHOR]

In order to observe and analyze the space of mutual electromagnetic interference from different aspects and perspectives, this paper took advantage of the characteristics of the boundaries of the isosurface to divide the radars mutual electromagnetic interference space. It measured the degree of the radars mutual electromagnetic interference by energy flux density and interference margin in the warship formation. And it used a progressive grid sampling extremum octree to reconstruct the isosurface quickly. It employed the differential display mode of the isosurface to create a real-time interactive 3D chart with a top view, a front view and a side view, while displaying the simulation results of the radars mutual interference in the warship formation dynamically. This paper simulated 6 ships with 16 single-pulse radars to interfere each other. The result shows this method is feasible and effective. It can be applied to the real-time 3D visual simulation of the electromagnetic environment of the electromagnetic interference in the large scene. It can also be used in the 3D visual simulation of the UAV radar electromagnetic interference research and prevention. [ABSTRACT FROM AUTHOR]

Uncertainty for dynamic grid resource service, a quantitative analysis resources quality of service (QoS) of multiple resources co-allocation reservation strategy is presented in the paper. Based on the analysis of grid job QoS metrics running on the resources, the model obtain the QoS satisfaction quantification, normalization method and establish functional relationship between resource services QoS and reserved capacity. Additionally, the essay works out a balanced load multiple resources nodes co-allocation reservation strategy through the analysis of the relationship between the resource price and reserved capacity in the task cost constrains under the background of the market economy. The validity of the model and its algorithm are presented theoretically. The performance of the proposed strategy was simulated in a large-scale grid simulation system using the real task load of the practical grid system. The results show that the proposed co-reservation strategy outperforms traditional reservation strategy in terms of acceptance of task number, resource utilization and task delinquencies. [ABSTRACT FROM AUTHOR]

In order to enjoy location-based services without leaking the users' location information to untrusted location service provider, k-anonymous location privacy protection had been well studied. However, for the original k-anonymity algorithm, all users' location privacy would be leaked when the centralized anonymizer was controlled by hackers, and the network load was very heavy when making k-nearest neighbor inquiries; for the SpaceTwist algorithm, it could not guarantee k-anonymity. This paper proposed an incremental KNN query algorithm based on the grid of latitude-longitude for location privacy protection, it came from the classical k-anonymity algorithm hybridized with the SpaceTwist algorithm, using the grids of latitude-longitude instead of the precise coordinates reported to centralized anonymizer, and thus it could solve the above problems. Experiments show that the algorithm can save the network traffic between the anonymizer and the location service provider's servers. [ABSTRACT FROM AUTHOR]

In order to enhance the probability of common keys in neighbor nodes, reduce wireless sensor networks resource cost and further enhance connectivity of wireless sensor networks (WSNs), this paper proposed a key management scheme using matrix deployment and communication key for wireless sensor networks. It used way of 3 x 3 matrix to distribute the keys so as to the neighbor nodes have q common keys. In square grid using matrix deployment could enhance the threshold of common keys and reduce redundancy keys in each of node. Theoretic studies and figures of simulation show that the proposed scheme not only provides better performance in connectivity and security, but also obtains up to 100% reduction in the number keys. [ABSTRACT FROM AUTHOR]