Geospatial Information Resources Research Articles

Accuracy assessment of quasi-seamless hydrographic separation models in Malaysian waters

The hydrographic survey reduction using ellipsoid has been available since the advent of the global navigation satellite system (GNSS), with a potential to streamline operation and enhance bathymetric output. Spatially continuous separation surfaces connecting a chart datum (CD) to a geodetic ellipsoid is required for this technique. Universiti Teknologi Malaysia (UTM) has invented a new quasi-seamless separation model for Malaysian waters, known as the Malaysian Vertical Separation (MyVSEP) model, through semi-empirical models to capture the spatial variability of a tidal datum between coastal and offshore areas. A continuous vertical datum is established to develop MyVSEP models by combining the coastal and offshore datasets. The coastal datasets referred to the vertical reference point computed from coastal tide gauges, while the offshore datasets referred to the vertical reference surfaces derived from satellite altimetry. Mean sea level (MSL) or mean sea surface (MSS), mean dynamic topography (MDT), lowest astronomical tide (LAT), and highest astronomical tide (HAT) are the vertical datums involved in developing the continuous MyVSEP model. However, the integration of the vertical datum has only been conducted over the Peninsular Malaysia region. For Sabah and Sarawak, datum integration cannot be implemented due to the limitation of coastal datasets. The assessment of the integrated vertical datum with coastal tide gauges is discussed in this study. The finding shows that the root mean square error (RMSE) agreement between the integrated Universiti Teknologi Malaysia 2020 (iUTM20) model and coastal tide gauges yields below 2.0 cm. The iUTM20 lowest astronomical tide and highest astronomical tide models also show significant improvement compared to the altimetric-derived tidal models, which recorded the root mean square error agreement with coastal tide gauges of 1.8 cm and 2.0 cm, respectively. The development of a continuous vertical separation model for the Ellipsoidally Referenced Surveying technique indirectly optimizes marine geospatial information resources, especially for the National Hydrographic Centre in Malaysia.

A Theoretical Proposition for Spatial Data Infrastructure On-Going Improvement

The past three decades have seen technology become ubiquitous and impact on many fields academically and in professional practice. In geo-information, data acquisition and management have manifested through technologies such as global positioning systems, remote sensing, geographical information systems, unmanned aerial vehicles and improved photogrammetric processes. With all these improved technological capabilities, geospatial data collection, processing and dissemination have become possible in greater proportions. To reap from this technological boom, the geospatial information community has come up with a pervasive and network enabling concept called spatial data infrastructure (SDI). Over the years, several countries have embraced the SDI concept to shape policy, build and share geospatial information resources. Some levels of successes have been reported in number of developed countries while developing countries have struggled. For instance, in 2010, SDI state of play assessment results of nine African countries averaged 30.70 over 56 or 0.55 while the SDI readiness index of the same countries averaged 0.50 on an index scale of 0 to 1 in 2016. The 2010 and 2016 assessments concluded that in African countries, SDI development was slow. To address the problem of slow SDI development in Africa, this paper proposes an on-going improvement theoretical approach anchored on the theory of constraints.

DESIGN AND IMPLEMENTATION OF CROWDSOURCING BASED CHINA'S NATIONAL PUBLIC GEOSPATIAL INFORMATION COLLECTION SYSTEM

Abstract. As the basis of public geospatial information service, geospatial information data with wide coverage, strong timeliness, rich content and high positioning accuracy is the key infrastructure of geospatial infrastructure for building smart cities and digital China. How to collect and update massive geospatial information resources fast and efficiently has always been the bottleneck for the rapid development of surveying and mapping geospatial information science and technology and industries, and the construction of China's national spatial data infrastructure. At present, the mainstream of geospatial data collecting and updating in China is that the government and enterprise employ professional engineers to for this work, but the problems of professional and complex data processing process, data management level by level, closed and off-line data update mode lead to a relatively slow update rate and poor data actuality, which seriously restricted the applications of geospatial information service in the fields of government decision-making, planning and construction, resource and environment monitoring, and emergency response. The contributions to the geospatial information data from the public community has also been ignored. This paper addresses the issues of low efficiency on data collection and update occurring in China's national geospatial information service platform, proposing a solution for public geospatial data collection and update based on crowdsourcing. The key technologies of data collection, storage, reviews and publication are studied, and the basic technical process of online data update for the government and the public users is designed. In order to verify the effectiveness and practicality of the mode discussed above, a prototype system is developed by expanding China's national geospatial information service platform, which fulfilled data online collection and reviewing, such as POIs, roads, and residential areas. The system can provide new methods and reference ideas for the collection and update of spatial data for the national geospatial information public service platform. It is a useful supplement to the current spatial data collection and update, and has important significances.

Applying Geospatial Information and Services Capabilities Beyond the Battlespace

While geospatial information resources have traditionally imparted situational awareness in the battlespace, the past twenty years has witnessed broad adoption in other defense environments as well. This paper describes the major catalysts spurring broader investment and use of geospatial information and services (GI&S) beyond the battlespace and into a parallel defense installation mission area known as basingspace. Furthermore, the paper details how the benefits of GI&S for delivering shared situational awareness in both battlespace and basingspace has the National Guard poised to exploit geospatial technologies in a more strategic manner. This paper presents a concise history of how social and technical factors influenced the diffusion of applied geospatial technologies within the defense sector and the potential for greater unity of geospatial efforts for the Department of Defense and the nation.

DEVELOPING A CLOUD-BASED ONLINE GEOSPATIAL INFORMATION SHARING AND GEOPROCESSING PLATFORM TO FACILITATE COLLABORATIVE EDUCATION AND RESEARCH

Efficient online discovering and applying geospatial information resources (GIRs) is critical in Earth Science domain as while for cross-disciplinary applications. However, to achieve it is challenging due to the heterogeneity, complexity and privacy of online GIRs. In this article, GeoSquare, a collaborative online geospatial information sharing and geoprocessing platform, was developed to tackle this problem. Specifically, (1) GIRs registration and multi-view query functions allow users to publish and discover GIRs more effectively. (2) Online geoprocessing and real-time execution status checking help users process data and conduct analysis without pre-installation of cumbersome professional tools on their own machines. (3) A service chain orchestration function enables domain experts to contribute and share their domain knowledge with community members through workflow modeling. (4) User inventory management allows registered users to collect and manage their own GIRs, monitor their execution status, and track their own geoprocessing histories. Besides, to enhance the flexibility and capacity of GeoSquare, distributed storage and cloud computing technologies are employed. To support interactive teaching and training, GeoSquare adopts the rich internet application (RIA) technology to create user-friendly graphical user interface (GUI). Results show that GeoSquare can integrate and foster collaboration between dispersed GIRs, computing resources and people. Subsequently, educators and researchers can share and exchange resources in an efficient and harmonious way.

DEVELOPING A CLOUD-BASED ONLINE GEOSPATIAL INFORMATION SHARING AND GEOPROCESSING PLATFORM TO FACILITATE COLLABORATIVE EDUCATION AND RESEARCH

Abstract. Efficient online discovering and applying geospatial information resources (GIRs) is critical in Earth Science domain as while for cross-disciplinary applications. However, to achieve it is challenging due to the heterogeneity, complexity and privacy of online GIRs. In this article, GeoSquare, a collaborative online geospatial information sharing and geoprocessing platform, was developed to tackle this problem. Specifically, (1) GIRs registration and multi-view query functions allow users to publish and discover GIRs more effectively. (2) Online geoprocessing and real-time execution status checking help users process data and conduct analysis without pre-installation of cumbersome professional tools on their own machines. (3) A service chain orchestration function enables domain experts to contribute and share their domain knowledge with community members through workflow modeling. (4) User inventory management allows registered users to collect and manage their own GIRs, monitor their execution status, and track their own geoprocessing histories. Besides, to enhance the flexibility and capacity of GeoSquare, distributed storage and cloud computing technologies are employed. To support interactive teaching and training, GeoSquare adopts the rich internet application (RIA) technology to create user-friendly graphical user interface (GUI). Results show that GeoSquare can integrate and foster collaboration between dispersed GIRs, computing resources and people. Subsequently, educators and researchers can share and exchange resources in an efficient and harmonious way.

BORDERLESS GEOSPATIAL WEB (BOLEGWEB)

The effective access and use of geospatial information (GI) resources acquires a critical value of importance in modern knowledge based society. Standard web services defined by Open Geospatial Consortium (OGC) are frequently used within the implementations of spatial data infrastructures (SDIs) to facilitate discovery and use of geospatial data. This data is stored in databases located in a layer, called the invisible web, thus are ignored by search engines. SDI uses a catalogue (discovery) service for the web as a gateway to the GI world through the metadata defined by ISO standards, which are structurally diverse to OGC metadata. Therefore, a crosswalk needs to be implemented to bridge the OGC resources discovered on mainstream web with those documented by metadata in an SDI to enrich its information extent. A public global wide and user friendly portal of OGC resources available on the web ensures and enhances the use of GI within a multidisciplinary context and bridges the geospatial web from the end-user perspective, thus opens its borders to everybody. <br><br> Project “Crosswalking the layers of geospatial information resources to enable a borderless geospatial web” with the acronym BOLEGWEB is ongoing as a postdoctoral research project at the Faculty of Geodesy, University of Zagreb in Croatia (http://bolegweb.geof.unizg.hr/). The research leading to the results of the project has received funding from the European Union Seventh Framework Programme (FP7 2007-2013) under Marie Curie FP7-PEOPLE-2011-COFUND. The project started in the November 2014 and is planned to be finished by the end of 2016. This paper provides an overview of the project, research questions and methodology, so far achieved results and future steps.

BORDERLESS GEOSPATIAL WEB (BOLEGWEB)

Abstract. The effective access and use of geospatial information (GI) resources acquires a critical value of importance in modern knowledge based society. Standard web services defined by Open Geospatial Consortium (OGC) are frequently used within the implementations of spatial data infrastructures (SDIs) to facilitate discovery and use of geospatial data. This data is stored in databases located in a layer, called the invisible web, thus are ignored by search engines. SDI uses a catalogue (discovery) service for the web as a gateway to the GI world through the metadata defined by ISO standards, which are structurally diverse to OGC metadata. Therefore, a crosswalk needs to be implemented to bridge the OGC resources discovered on mainstream web with those documented by metadata in an SDI to enrich its information extent. A public global wide and user friendly portal of OGC resources available on the web ensures and enhances the use of GI within a multidisciplinary context and bridges the geospatial web from the end-user perspective, thus opens its borders to everybody. Project “Crosswalking the layers of geospatial information resources to enable a borderless geospatial web” with the acronym BOLEGWEB is ongoing as a postdoctoral research project at the Faculty of Geodesy, University of Zagreb in Croatia (http://bolegweb.geof.unizg.hr/). The research leading to the results of the project has received funding from the European Union Seventh Framework Programme (FP7 2007-2013) under Marie Curie FP7-PEOPLE-2011-COFUND. The project started in the November 2014 and is planned to be finished by the end of 2016. This paper provides an overview of the project, research questions and methodology, so far achieved results and future steps.

An integrated geospatial information service system for disaster management in China

The Chinese Government and citizens face enormous challenges of disaster management as widespread devastation, economic damages, and loss of human lives caused by increasing natural disasters. Disaster management requires a complicated iterative process that includes disaster monitoring, early detection, forecasting, loss assessment, and efficient analysis of disaster reduction. Each task typically involves the use of technologists and multiple geospatial information resources, including sensors, data sources, models, geo-tools, software packages, and computing resources. However, most existing disaster management systems operate in a typical passive data-centric mode, where resources cannot be fully utilized. This impediment is partially being addressed by the increasingly complex application requirements and the growing availability of diverse resources. In this paper, we summarize and analyze the practical problems experienced by the National Disaster Reduction Application System of China. To address the issues of data-centric, centralized, isolated solutions, we propose a novel Focusing Service Mechanism, which is capable of scheduling and allocating for optimum utilization of multiple resources, to dynamically generate collaborative and on-demand disaster information services. We also demonstrate the design and implementation of the Integrated Disaster Information Service System (IDISS). Through the service strategies of Virtualizing, Wrapping, and Integrating, disaster-related resources are constructed into services in the IDISS. These services are dynamically aggregated into focusing service chains, for diverse disaster management tasks. Actual applications illustrate that the proposed service system can significantly improve the capability of disaster management in China.

An approach for heterogeneous and loosely coupled geospatial data distributed computing

Most GIS (Geographic Information System) applications tend to have heterogeneous and autonomous geospatial information resources, and the availability of these local resources is unpredictable and dynamic under a distributed computing environment. In order to make use of these local resources together to solve larger geospatial information processing problems that are related to an overall situation, in this paper, with the support of peer-to-peer computing technologies, we propose a geospatial data distributed computing mechanism that involves loosely coupled geospatial resource directories and a term named as Equivalent Distributed Program of global geospatial queries to solve geospatial distributed computing problems under heterogeneous GIS environments. First, a geospatial query process schema for distributed computing as well as a method for equivalent transformation from a global geospatial query to distributed local queries at SQL (Structured Query Language) level to solve the coordinating problem among heterogeneous resources are presented. Second, peer-to-peer technologies are used to maintain a loosely coupled network environment that consists of autonomous geospatial information resources, thus to achieve decentralized and consistent synchronization among global geospatial resource directories, and to carry out distributed transaction management of local queries. Finally, based on the developed prototype system, example applications of simple and complex geospatial data distributed queries are presented to illustrate the procedure of global geospatial information processing.

Performance Issues of GML Vector Data on Wireless Access Networks

With regarding to web GIS, Open Geospatial Consortium promotes Web Feature Service allowing a client to retrieve geospatial data encoded in GML which is a modeling language to encode the semantics, syntax and schema of geospatial information resources. Even though GML provides benefits for geographic description, it is too heavy for mobile devices to process. In order to address the issue, this paper evaluates a GML service with a WFS server and GML viewers. Through this paper, we analyze properties of GML geospatial data and effects on wireless environments.