Qingyun Du

DESIGN AND IMPLEMENTATION OF A WEB INTERACTIVE THEMATIC CARTOGRAPHY METHOD BASED ON A WEB SERVICE CHAIN

There is a tendency toward the creation of thematic maps on the web in the ongoing development of cartographic technology. However, automatically creating maps through the web and creating interactive web maps are two challenges associated with this field. To solve these problems, a web thematic cartography method based on a web service chain is presented here. Automated cartography is performed through knowledge-based web cartographic services, and interacting with the services is possible. The method is implemented in the construction of a urban thematic atlas in Shenzhen, China that is dedicated to supporting decision making for urban planning and public participatory thematic map making on the web.

Research on designing ontologies for location-based services

With the far and wide applications of Location-Based Services (LBS), the call for more semantic and accurate services is emerging. From a semantic viewpoint, the major characteristic of, and challenge for, LBS is the fact that they serve as mediator between a possibly unknown user and possibly a priori unknown services. While some geographic information technology standards provide the basis for syntactic interoperability, they do not yet provide methods for dealing with problems of semantic heterogeneity. In this paper we design ontologies for LBS which are used for the identification and association of semantically corresponding concepts to overcome the semantic problems. In order to better understand the semantic content of the data in LBS, we analyze several elements both data and services involved. Then, we model these data and services in a way that captures their peculiarities and allows their sharing between users and services and exchange among different LBS, when desired. For this, we use the Protégé-OWL plug-in for creating hybrid hierarchy of ontologies to enhance the semantic content both the user information and the services have. To argue about the design choices and show their applicability, we present a simple example from a characteristic real world application.

The further development of legal cadastral domain model of China based on ontology

The cadastral plays a very important role in managing spatial and non-spatial legal real property information. And the legal aspect is the important component of the cadastral. And the success of a cadastral system is not dependent on its legal or technical sophistication, but whether it protects land rights adequately and permits those rights to be traded (where appropriate) efficiently, simply, quickly, securely and at low cost. However, the ambiguity of legal cadastral domain has been the major barrier to data integration and interoperability. This paper intends to optimize the concept model of legal cadastral domain based on the model established in my previous paper which can be a first step towards facilitate the effective interchange of cadastral information and the administration of land use. And the way expressing these conceptions and relationships between them was an object-oriented approach in ontology principles. The outcome of this paper is also a basic but better expression legal cadastral domain model of china.

Simulation on the effects of non-point source pollution in Qingjiang River basin based on SWAT model and GIS

Assessment of the pollution of water bodies from non-point sources (NPS) is a complex data-requiring and time-consuming task. The accuracy of NPS pollution models depends to a great extent on how well model input parameters describe the relevant characteristics of the watershed. It is assumed that promoting the precision of input parameters affects the simulation results of runoff, sediment and nutrients yield from the entire watershed. An integration of simulating model with GIS technique is one of the most efficient methods to NPS pollution quantified research at present. In this study, the basic database, which includes DEM, soil and landuse map, climate data, and land management data, were established for the study purpose using GIS. The generation and formation of non-point source pollution involves great uncertainty, and this uncertainty makes monitoring and controlling pollution very difficult. Understanding the main parameters that affect NPS pollution uncertainty is necessary to provide the basis for the planning and design of control measures. Based on the results of parameter sensitivity analysis, the sensitive parameters of Soil and Water Assessment Tool (SWAT) model were identified, and then model parameters related to stream flow and nutrient loadings were calibrated and validated by the observed value, and the simulation showed that the simulated values were reasonably comparable to the observed data, suggesting the validity of SWAT model. The spatial-temporal distribution features of NPS pollution in the Qingjiang River basin (a case study of this paper which is one main branch of Yangtze River basin in Three Gorges Project area) were revealed. NPS pollution mainly takes place in flood season. The critical risk areas of soil erosion were identified. Stream flow and nutrient loadings (including total nitrogen (TN) and total phosphorus (TP)) in Qingjiang River Basin were simulated. The surface runoff and nutrient yield results indicated that the average annual runoff and output of TN and TP provides better understanding on stream flow and nutrient loadings responding to variations of land use conditions, agricultural tillage operation and natural rainfall etc.

Research on land registration procedure ontology of China

Land registration is public act which is to record the state-owned land use right, collective land ownership, collective land use right and land mortgage, servitude, as well as other land rights required the registration according to laws and regulations onto land registering books. Land registration is one of the important government affairs , so it is very important to standardize, optimize and humanize the process of land registration. The management works of organization are realized through a variety of workflows. Process knowledge is in essence a kind of methodology knowledge and a system which including the core and the relational knowledge. In this paper, the ontology is introduced into the field of land registration and management, trying to optimize the flow of land registration, to promote the automation-building and intelligent Service of land registration affairs, to provide humanized and intelligent service for multi-types of users . This paper tries to build land registration procedure ontology by defining the land registration procedure ontologys key concepts which represent the kinds of processes of land registration and mapping the kinds of processes to OWL-S. The land registration procedure ontology shall be the start and the basis of the Web service.

Modeling the Dynamics of Urban Growth Using Multinomial Logistic Regression : A Case Study of Jiayu County, Hubei Province, China

Urban growth modeling, one of the most important aspects of land use and land cover change study, has attracted substantial attention because it helps to comprehend the mechanisms of land use change thus helps relevant policies made. This study applied multinomial logistic regression to model urban growth in the Jiayu county of Hubei province, China to discover the relationship between urban growth and the driving forces of which biophysical and social-economic factors are selected as independent variables. This type of regression is similar to binary logistic regression, but it is more general because the dependent variable is not restricted to two categories, as those previous studies did. The multinomial one can simulate the process of multiple land use competition between urban land, bare land, cultivated land and orchard land. Taking the land use type of Urban as reference category, parameters could be estimated with odds ratio. A probability map is generated from the model to predict where urban growth will occur as a result of the computation.

Augmented reality technology and application in aerodrome building

Paper discusses the function and meaning of AR in the aerodrome construction project. In the initial stages of the aerodrome building, it applies the advanced technology including 3S (RS, GIS and GPS) techniques, augmented reality, virtual reality and digital image processing techniques, and so on. Virtual image or other information that is created by the computer is superimposed with the surveying district which the observer stands is looking at. When the observer is moving in the district, the virtual information is changing correspondingly, just like the virtual information really exists in real environment. The observer can see the scene of aerodrome if he puts on clairvoyant HMD (head mounted display). If we have structural information of the aerodrome in database, AR can supply X-ray of the building just like pipeline, wire and framework in walls.

Resolution of spatial conflict between road networks based on the improved snake model

In the paper, the main method we discuss and improve relates to the snake model, which is used to displace the roads and resolve the conflict. A snake is an energy-minimizing spline guided by internal constraint forces and influenced by external enforcement. In the paper, the theory of snake model is illustrated in detail. Then, according to the demand of cartography, the snake model is improved as follows. First, the relationship between the parameters of snake and shape character of road is built up in order to keep the shape of displaced road better. Second, the propagation extent of external force in snake model is controlled to keep the accuracy of road position. Third, the power attribute of intersection point between roads is set to control the displacement of the intersection point and keep the topological relationship of roads. At last, the general thought of disposing the spatial conflict of road networks are brought forward by using the improved snake model. One experiment research is made in terms of the general thought, which represents that the roads are displaced and the spatial conflicts are solved well.

Research on open spatial information visualization system (OSIVS)

The software is now transferring from special system to open systems, which is easier to use and more self-adaptive. In this paper, the research on the an open visualization systems, Open Spatial Information Visualization System (OSIVS) is put forward. Firstly, by analyzing some existing open systems and concepts, the authors give the concept of Open Spatial Information Visualization System, and put forward some idea to build an OSIVS. Secondly, the authors describe a prototype system in details by analyzing an OSIVS developed by Institute of Geographical Sciences and Natural Resources Research. Finally, the conclusions are made on the research of OSIVS and its relationship to Self-adaptive Spatial Information System.