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41.
This study was initiated to examine the feasibility of providing multimedia mail, in particular video mail, on the existing World Wide Web platform. In this instance, the Web browser will act as the user agent of the mailing system. With this, users will be able to compose, send and read video mail directly on the Web. This paper examines a number of possible system architectures that can be employed for the development of video mail. Based on the following key issues: portability of system, flexibility of system, Internet standard support, security and authentication, and message compression and storage, a final architecture was selected to build video mail. The approach taken is that the system will be interfaced to the Web using a standard HyperText Transfer Protocol (HTTP) server and a standard Web browser. This is achieved through the use of Common Gateway Interface (CGI) programs and forms which reside in a standard HTTP server to provide the functionality of video mail, and a separate mail server for the storage and management of messages. This will cause the HTTP server to behave as if it is an electronic mail (E-mail) system. Video mail has been successfully implemented at the School of Applied Science, Nanyang Technological University, Singapore. The development work has been carried out on a Sun SPARC5 workstation and the Typhoon relational database system was used to construct the mail server. All software codes were written in C or C++. A video capturing application used in conjunction with a SunVideo card has been developed for video and audio recording. The paper also addresses implementation issues pertaining to the use of CGI programs, mail server development, and video and audio management.  相似文献   
42.
New inorganic–organic hybrid structures based on metal complexes have become of increasing interest over the last few decades in the search for new materials. Many different polypyridyl metal complexes have been investigated. Recently, a strong increase in interest regarding 2,2′:6′,2″‐terpyridine has been observed. In particular, octahedral bis‐2,2′:6′,2″‐terpyridine metal complexes offer the advantages of increased symmetry and, in the case of ruthenium(III )/ruthenium(II ) complexation, an entrance to a directed complexation technique. Apart from the combination with polymeric systems, ordered inorganic–organic structures on surfaces are becoming better understood concurrently with the development of sophisticated nanotechnology characterization techniques. There are many ongoing efforts that include terpyridine complex structures, especially concerning photophysical processes such as solar light to energy conversion. This review deals with the incorporation of terpyridine complexes into polymeric structures such as poly(ethylene glycol), poly(styrene), dendrimers, biomacromolecules, micelles, and resins, as well as the combination of terpyridine complexes with surfaces for electrocatalytic, photophysical, and self‐assembly purposes.  相似文献   
43.
Imaging of edges to nanometer resolution using a novel non-contact technique is presented. This technique relies on positioning an optical beam to the edge, and simultaneously scanning, and measuring differential changes in off-specular scatter. Data may be used to calculate the radius at the edge to high accuracy. The experimental apparatus is capable of producing diffraction images of features on surfaces arising from processes used in sample preparation. Images of the cleaved edge of an optical fiber, an Au pad on Si, and cleaved quartz measured on this apparatus are presented. This technique could also be utilized to analyze cleaved laser diodes, micro-optics, MEMS devices, and diamond cutting tools.  相似文献   
44.
This review summarizes the results obtained in a research programme sponsored by the Ministry of Interior of the FRG on fundamental principles of a structural design code for heat exchanging components in nuclear process heat plants. Materials selection and design data, methods for dimensioning and the limitation of stress, strain, creep fatigue and buckling as well as environmental effects are discussed.  相似文献   
45.
The structure of the metalloproteinase and hemorrhagic toxin atrolysin C form d (EC 3.4.24.42), from the venom of the western diamondback rattlesnake Crotalus atrox, has been determined to atomic resolution by x-ray crystallographic methods. This study illuminates the nature of inhibitor binding with natural (< Glu-Asn-Trp, where < Glu is pyroglutamic acid) and synthetic (SCH 47890) ligands. The primary specificity pocket is exceptionally deep; the nature of inhibitor and productive substrate binding is discussed. Insights gained from the study of these complexes facilitate the design of potential drugs to treat diseases where matrix metalloproteinases have been implicated, e.g., arthritis and tumor metastasis.  相似文献   
46.
Outlier detection research has been seeing many new algorithms every year that often appear to be only slightly different from existing methods along with some experiments that show them to “clearly outperform” the others. However, few approaches come along with a clear analysis of existing methods and a solid theoretical differentiation. Here, we provide a formalized method of analysis to allow for a theoretical comparison and generalization of many existing methods. Our unified view improves understanding of the shared properties and of the differences of outlier detection models. By abstracting the notion of locality from the classic distance-based notion, our framework facilitates the construction of abstract methods for many special data types that are usually handled with specialized algorithms. In particular, spatial neighborhood can be seen as a special case of locality. Here we therefore compare and generalize approaches to spatial outlier detection in a detailed manner. We also discuss temporal data like video streams, or graph data such as community networks. Since we reproduce results of specialized approaches with our general framework, and even improve upon them, our framework provides reasonable baselines to evaluate the true merits of specialized approaches. At the same time, seeing spatial outlier detection as a special case of local outlier detection, opens up new potentials for analysis and advancement of methods.  相似文献   
47.
Electropolymerization represents a suitable and well‐established approach for the assembly of polymer structures, in particular with regard to the formation of thin, insoluble films. Utilization of monomers that are functionalized with metal complex units allows the combination of structural and functional benefits of polymers and metal moieties. Since a broad range of both electropolymerizable monomers and metal complexes are available, various structures and, thus, applications are possible. Recent developments in the field of synthesis and potential applications of metal‐functionalized polymers obtained via electropolymerization are presented, highlighting the significant advances in this field of research.  相似文献   
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The WWW has become one of the most important media for sharing information. Web information provides another emerging and important avenue and source of competitive intelligence (CI) for companies. CI is critical for companies to stay competitive in the marketplace. Apart from business users, there are other types of CI users such as technical users, casual users, news awareness users and others who would like to be kept informed on the latest development of their interested areas over the WWW. To discover web information, CI users need to constantly monitor certain web sites and web pages for related information. However, the dynamic nature of the web has made such monitoring task complicated and time-consuming. This paper proposes a web monitoring system, WebMon, to help users monitor specified web pages for latest changes and updates in information. Four monitoring functions including date monitoring, keywords monitoring, link monitoring and portion monitoring are supported by the system. The performance of these monitoring functions is also evaluated.  相似文献   
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