Land potential appraisal for urban land reserve based on GIS：

With the rapid urbanization, land banking has become an important means for rational land use and land configuration optimizing. Rational urban land reserve and supply plan are keys for an urban land banking. GIS has been used to model urban growth, growth at the ruralurban fringe specifically. This paper identifies that the urban land banking potential can be evaluated based on RS and GIS technology. 10 indicators were chosen in the integrated index system. As a case of Metropolitan area in Chongqing, urban land banking potential was evaluated based on RS and GIS technology. With GIS, two steps can help to finish potential analysis of land banking. One is goal driven process, such as the process of planning and definition; the other step is datadriven process, such as the process of Manipulating. The results are used to establish the current land banking plan.      

Services oriented architecture of foundation data platform of digital city

Digital city, a large complex system, is comprised many subsystem of different fields. It involves common field data, flexible field processes, seamless intra-organization and inter-organization collaborations, and increasing connectivity and interoperability between distributed or decentralized systems. All above these are involved Foundation Data of Digital city. To promote the sustainable development of Digital City, this paper investigates to the construction of Foundation Data Platform (FDP) from the view of the architecture. The paper introduces the conceptions, characteristics and underlying problems of the FDP, and discusses the key issues of the architecture paradigms what FDP might adopted via comparing Object-Oriented Architecture (OOA), Component-Based Architecture (CBA), and Service-based Architecture (SBA). The Process Embedded Service-Oriented Architecture (SOA), one of the recent SOA Application Architecture is introduced. The results indicate that the Process Embedded SOA could promote the sustainable development of Digital City and accommodate the dynamic development environments of different fields which constantly changes requirements.     

An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available，and able to support on-line scaling without interrupting service. To support more client’s queries without downtime and degrading the response time，more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use，i.e.，we decrease the number of data copy by reusing te backup data. Also，our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An efficient selectivity estimation method for spatial query optimization with topological relationships

Many commercial database systems maintain histograms to summarize the contents of relations and permit the efficient estimation of query result sizes and the access plan cost. In spatial database systems,most spatial query predicates are consisted of topological relationships between spatial objects,and it is very important to estimate the selectivity of those predicates for spatial query optimizer. In this paper, we propose a selectivity estimation scheme for spatial topological predicates based on the multidimensional histogram and the transformation scheme. Proposed scheme applies two-partition strategy on transformed object space to generate spatial histogram and estimates the selectivity of topological predicates based on the topological characteristics of the transformed space. Proposed scheme provides a way for estimating the selectivity without too much memory space usage and additional I/Os in most spatial query optimizers.     

Density-based clustering method in the moving object database

With the rapid advance of wireless communication, tracking the positions of the moving objects is becoming increasingly feasible and necessary. Because a large number of people use mobile phones, we must handle a large moving object database as well as the following problems. How can we provide the customers with high quality service, that means, how can we deal with so many enquiries within as less time as possible? Because of the large number of data, the gap between CPU speed and the size of main memory has increasing considerably. One way to reduce the time to handle enquiries is to reduce the I/O number between the buffer and the secondary storage. An effective clustering of the objects can minimize the I/O cost between them. In this paper, according to the characteristic of the moving object database, we analyze the objects in buffer, according to their mappiigs in the two-dimension coordiiate, and then develop a density-based clustering method to effectively reorganize the clusters. This new mechanism leads to the less cost of the I/O operation and the more efficient response to enquiries.     

A recovery method using recently updated record information in shared-nothing spatial database cluster

A shared-nothing spatial database cluster is system that provides continuous service even if some system failure happens in any node. So,an efficient recovery of system failure is very important. Generally,the existing method recovers the failed node by using both cluster log and local log. This method,however,cause several problems that increase communication cost and size of cluster log. This paper proposes novel recovery method using recently updated record information in shared-nothing spatial database cluster. The proposed technique utilizes update information of records and pointers of actual data. This makes a reduction of log size and communication cost. Consequently,this reduces reccvery time of failed node due to less processing of update operations.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents. A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented,low cost and adapt to all kinds of mobile nework system.     

Version based spatial record management techniques for spatial database management system

The search operation of spatial data was a principal operation in existent spatial database management system, but the update operation of spatial data such as tracking are occurring frequently in the spatial database management system recently. So, necessity of concurrency improvement among transactions is increasing. In general database management system, many techniques have been studied to solve concurrency problem of transaction. Among them, multi-version algorithm does to minimize interference among transactions. However, to apply existent multi-version algorithm to improve concurrency of transaction to spatial database management system, the waste of storage happens because it must store entire version for spatial record even if only aspatial data of spatial record is changed. This paper has proposed the record management techniques to manage separating aspatial data version and spatial data version to decrease waste of storage for record version and improve concurrency among transactions.     

Operator scheduling strategy for LBS-based intelligent transportation system

With the development of location technologies, advanced LBS-based ITS increasingly requires the capability of database technologies to manage the continuously arrived vehicles' location, traffic jam and other interrelated information of large amounts of traffic in the following years. And some burst arrival stream data will challenge the real-time performance and the allocation of limited resource. However, choosing a desirable database operator scheduling strategy can significantly improve the performance of the system. The path capability strategy was chosen and improved as ITS' operator scheduling strategy to meet the real-time response and the minimal memory requirement of the system.     

Land potential appraisal for urban land reserve based on GIS: A case of metropolitan area in Chongqing

With the rapid urbanization, land banking has become an important means for rational land use and land configuration optimizing. Rational urban land reserve and supply plan are keys for an urban land banking. GIS has been used to model urban growth, growth at the rural-urban fringe specifically. This paper identifies that the urban land banking potential can be evaluated based on RS and GIS technology. 10 indicators were chosen in the integrated index system. As a case of Metropolitan area in Chongqing, urban land banking potential was evaluated based on RS and GIS technology. With GIS, two steps can help to finish potential analysis of land banking. One is goal driven process, such as the process of planning and definition; the other step is data-driven process, such as the process of Manipulating. The results are used to establish the current land banking plan.