In order to support users to search and browse for various resources, digital libraries are composed of discovery systems which provide user interface and information retrieve system. Recent researches in Information ...In order to support users to search and browse for various resources, digital libraries are composed of discovery systems which provide user interface and information retrieve system. Recent researches in Information Retrieval have investi- gated different techniques through improving precision and recall to enhance the effectiveness of discovery system in digital libraries. In this paper, we present our work to enhance discovery system effectiveness with a different approach, through resource discovery based on visual knowledge navigation. In our Strand Map Services project under National Science Digital Library, we introduce the visual resource discovery system called conceptual browsing interfaces, to help educators and learners to locate, comprehend and use educational resources in digital libraries. The paper begins with a short introduction of the Strand Map Services. Then we illustrate the service architecture, the design and implementation of its major components. We will focus our discussion of how the visualization system of the Strand Map Services supports the visual knowledge navigation for distributed digital libraries. This includes the knowledge acquisition of the conceptual browsing interfaces, different knowledge representa- tions in the system perspective and user interface perspective, visualization system modules, algorithm and Web services inte- gration to use visual knowledge navigation to enhance resource discovery in digital libraries.展开更多
Wireless radio spectrum is an important resource that allows for increased business development, throtigh the provision of services using wireless networking infrastructures. Since radio spectrum is limited, an optima...Wireless radio spectrum is an important resource that allows for increased business development, throtigh the provision of services using wireless networking infrastructures. Since radio spectrum is limited, an optimal utilization of it is required, by adopting advanced spectrum management methods. The current transition from analogue to digital terrestrial television may act as a unique opportunity, in order to reallocate this valuable spectrum resource. After the transition, a part of the traditional analogue television spectrum bands will be completely released, allowing for the use of this spectrum by sophisticated wireless systems. Furthermore, digital terrestrial television interleaves spectrum bands in order to avoid possible interference between adjacent channels used by broadcasting stations, thus leaving spectrum holes exploited by novel wireless networks, namely unlicensed secondary systems. In this context, this article investigates business and marketing development issues, arising by utilizing released and interleaved television spectrum bands展开更多
文摘In order to support users to search and browse for various resources, digital libraries are composed of discovery systems which provide user interface and information retrieve system. Recent researches in Information Retrieval have investi- gated different techniques through improving precision and recall to enhance the effectiveness of discovery system in digital libraries. In this paper, we present our work to enhance discovery system effectiveness with a different approach, through resource discovery based on visual knowledge navigation. In our Strand Map Services project under National Science Digital Library, we introduce the visual resource discovery system called conceptual browsing interfaces, to help educators and learners to locate, comprehend and use educational resources in digital libraries. The paper begins with a short introduction of the Strand Map Services. Then we illustrate the service architecture, the design and implementation of its major components. We will focus our discussion of how the visualization system of the Strand Map Services supports the visual knowledge navigation for distributed digital libraries. This includes the knowledge acquisition of the conceptual browsing interfaces, different knowledge representa- tions in the system perspective and user interface perspective, visualization system modules, algorithm and Web services inte- gration to use visual knowledge navigation to enhance resource discovery in digital libraries.
文摘Wireless radio spectrum is an important resource that allows for increased business development, throtigh the provision of services using wireless networking infrastructures. Since radio spectrum is limited, an optimal utilization of it is required, by adopting advanced spectrum management methods. The current transition from analogue to digital terrestrial television may act as a unique opportunity, in order to reallocate this valuable spectrum resource. After the transition, a part of the traditional analogue television spectrum bands will be completely released, allowing for the use of this spectrum by sophisticated wireless systems. Furthermore, digital terrestrial television interleaves spectrum bands in order to avoid possible interference between adjacent channels used by broadcasting stations, thus leaving spectrum holes exploited by novel wireless networks, namely unlicensed secondary systems. In this context, this article investigates business and marketing development issues, arising by utilizing released and interleaved television spectrum bands