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Necessary and sufficient conditions are obtained for the realization of an m-variable positive real function (PRF) as the impedence function of a resistively-terminated ladder network of m lossless two-ports connected in cascade. Each two-port is a single-variable lossless ladder with all of its transmission zeros either at the origin or at finity. Conditions are also obtained when each of the two-ports is a Fujisawa-type lowpass ladder.  相似文献   
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The effect of solute Cu and Cu precipitates on the wear behavior of ferritic iron under an unlubricated condition was investigated. The specific wear rate of Cu-containing steel abruptly decreased up to 50 N of load, and then gradually decreased with further increased load. The specific wear rate of the as-quenched specimen, in which Cu was in a solid solution, was the lowest among all the specimens at low loads, and all specimens had almost the same specific wear rate at high loads. Subsurface observation showed that the hardness increments of all specimens decreased with increased depth below the worn surface. The as-quenched specimen had a relatively large depth of deformed region than the other specimens even though the increments in hardness were almost the same for all specimens at low loads. With the same hardness at an unworn state, the as-quenched and over-aged specimens exhibited a substantial increase in hardness and large deformed regions below the worn surfaces. This finding indicated that the enhancement in plastic deformation and work hardening led to the decrease in the specific wear rate of the as-quenched specimen at low loads and the improvement in the wear resistance of all specimens at high loads.  相似文献   
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This paper traces the transmission of Western science through the agricultural education sector during the British colonial administration of Malaya. This education system included three levels: elementary, intermediate and the school of agriculture. To understand the process by which Western science was transmitted in Malaya, Basalla’s model was adopted to clarify the vectors of Western science and the types of knowledge disseminated by these vectors, and to identify the mechanisms sustaining scientific research activities outside Europe. This paper shows that the transmission and the diffusion of Western science through education were highly centralised under the British colonial umbrella and closely associated with the agricultural economy.  相似文献   
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This study attempts to identify the factors perceived to be important in choosing an Institution of Higher Learning (IHL) for distance learning. One thousand five hundred questionnaires were distributed to the first year students in the social sciences distance learning programs and 980 valid responses were received of Malaysian public university. The results show that the top three factors influencing their preferred institution are qualification recognition IHL, future career advancement, and personal satisfaction. The results of this study provide insights to the IHL, employers and academics on the nature and relative importance of the factors perceived important for adult learners in the selection of their preferred IHL.  相似文献   
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ABSTRACT

Differences and similarities between table tennis and other racquet sports exist, but are not well documented in the literature, in spite of the relevance for talent identification. In this study we aimed at identifying the key characteristics of table tennis in comparison with tennis and badminton based upon a survey in coaches. A total of 177 licensed coaches from all across the world and with diverse professional backgrounds completed a survey on anthropometric measures, physical performance, and motor coordination skills. On a scale from 1 to 10, coaches indicated to what extent a talent characteristic was important for their sport. MANOVA identified key differences as well as similarities between all three racquet sports and a subsequent discriminant analysis allocated coaches correctly for table tennis, tennis, and badminton 81.01%, 55.6%, and 71.4% respectively. Our results show that table tennis and other racquet sport coaches are well aware of differences between the racquet sports and also the importance and value of testing and assortment of skill components. These findings can assist coaches in future talent orientation and transfer in racquet sports.  相似文献   
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Modern organized international badminton began with the founding of the International Badminton Federation (IBF) in 1934, consisting of nine founding member associations. The inaugural men’s Thomas Cup tournament began in 1948 when 10 countries took part. Malaya won the Cup four times in 1949, 1952, 1955, and 1967. When Indonesia took part in the tournament for the first time in 1957, there were 19 competing teams. Indonesia won the triannual tournament seven times from 1957 to 1979. Throughout the 11 Thomas Cup tournaments, only two Asian countries have won the Cup. The only European country, Denmark, qualified to play in the finals five times without a single win. Malaya (later known as Malaysia), Indonesia, and Denmark became leading Thomas Cup teams because they produced singles and doubles players that won many All-England Badminton Championship titles. The winners of these titles were generally considered the world champions. The key sources of information for this research consisted of the IBF annual statutes for listing of participating nations, tournament programmes, and rare specialized books on badminton and the Thomas Cup competition. English language newspapers such as the Singapore Free Press and the Straits Times published historical match results for checking the secondary data collected.  相似文献   
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INTRODUCTION In this paper, we present our work in the Strand Map Service (SMS), which provides concept map based browsing interfaces for resource discovery in a library independent manner within American Na- tional Science Digital Library (NSDL). As critical components of digital libraries, dis- covery systems provide interfaces that support user to search and browse for resources in digital libraries (Hall et al., 1999). The effectiveness of discovery systems has big impact on the…  相似文献   
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