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1.
This article reports the findings of a scientometric analysis of nanoscale research in South Africa during the period 2000–2005. The ISI databases were identified as the most appropriate information platform for the objectives of the investigation and have been interrogated for the identification of South African authors publishing in the field. The article identifies trends over time, major institutional contributors, journals in which South African authors publish their research, international collaborators and performance in comparison to four comparator countries (India, Brazil, South Korea and Australia). The major findings of the investigation are as follows: nanoscale research in South Africa is driven by individual researchers interests up to date and it is in its early stages of development; the country’s nanoscale research is below what would one expect in light of its overall publication output; the country’s nano-research is distributed to a number of Universities with subcritical concentration of researchers.  相似文献   
2.
While surgical practices are increasingly reliant on a range of digital imaging technologies, the ability for clinicians to interact and manipulate these digital representations in the operating theatre using traditional touch based interaction devices is constrained by the need to maintain sterility. To overcome these concerns with sterility, a number of researchers are have been developing ways of enabling interaction in the operating theatre using touchless interaction techniques such as gesture and voice to allow clinicians control of the systems. While there have been important technical strides in the area, there has been little in the way of understanding the use of these touchless systems in practice. With this in mind we present a touchless system developed for use during vascular surgery. We deployed the system in the endovascular suite of a large hospital for use in the context of real procedures. We present findings from a study of the system in use focusing on how, with touchless interaction, the visual resources were embedded and made meaningful in the collaborative practices of surgery. In particular we discuss the importance of direct and dynamic control of the images by the clinicians in the context of talk and in the context of other artefact use as well as the work performed by members of the clinical team to make themselves sensable by the system. We discuss the broader implications of these findings for how we think about the design, evaluation and use of these systems.  相似文献   
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Scientific co-authorship of African researchers has become a fashionable topic in the recent scientometric literature. Researchers are investigating the effects, modes, dynamics and motives of collaboration in a continental research system which is in an embryonic stage and in different stages of development from country to country. In this article we attempt to provide some additional evidence by examining both patterns of collaboration at country and continental levels and the scientific disciplines emphasised. Our findings indicate that the continent’s research emphasises medical and natural resources disciplines to the detriment of disciplines supporting knowledge based economies and societies. Furthermore, we identify that the collaborative patterns in Africa are substantial higher than in the rest of the world. A number of questions related to research collaboration and its effects are raised.  相似文献   
5.
This article aims to provide scientometric evidence in order to confirm or refute the statement that the “rise in literalist religious thinking in the 1990s devastated science in the Islamic world by promoting the idea that all knowledge could be found in the Koran” published in a Special Report in the New Scientist and to map the literature related to fundamentalism over time and space during the last ten years. We find that despite the rise of fundamentalism, science was thriving in eight Islamic countries (Iran, Jordan, Indonesia, Egypt, Turkey, Malaysia, Morocco, and Pakistan) during the period and hence the statement is refuted. The mapping of the “fundamentalist” literature indicates that there are a constant number of articles per year (60 to 70) covering disciplines ranging from religion and sociology to political sciences and international relations. The center of research is revealed to be the Anglo-Saxon world with epicenter the USA. Finally, we identify that the debate of fundamentalism versus science is in an embryonic stage.  相似文献   
6.
This article introduces the Special Section, which explores the potential importance of positive emotions in our theory, research, and practice. The authors propose that the peripheral role that psychotherapy theory, research, and practice has allotted to the variable "positive emotion" can be understood in terms of the foundational axioms of our discipline. The authors argue that psychotherapy has implicitly adopted an attitude of caution and suspicion toward the potential therapeutic value of experiencing positive emotions, an all embracing attitude toward the therapeutic value of experiencing negative emotions, and an identity focused on healing psychological wounds at the expense of promoting psychological well-being. The authors trace the adoption of these axioms to Judeo-Christian ideas of human nature and to the identity formation process of psychotherapy, and the authors speculate on the sociopolitical forces that have promoted a shift in our theorizing in the last few decades. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
The HIV/AIDS pandemic is of international interest with the 2008 Nobel Prize in physiology or medicine having being awarded for the discovery of the virus that causes AIDS. South Africa has a particular interest in the field of HIV/AIDS research as it is the country with the largest number of HIV infections in the world and the issue has created a number of political and scientific debates. This investigation identifies the state of HIV/AIDS related research in South Africa vis-a-vis the rest of the world using evaluative scientometrics in order to inform relevant policy. South Africa is identified as producing an increasing number of HIV/AIDS related publications, making it one of the most prolific fields in the country. The rest of the world appears to have stabilized its research efforts after the development of highly active antiretroviral therapies. The USA is identified as the main producer of HIV/AIDS research while Europe appears to under-emphasise the issue. Comparison of the world??s most prolific universities with those in South Africa identifies that the latter has a fragmented system. A number of policy issues are discussed.  相似文献   
8.
We address the problem of routing connection-oriented traffic in wireless ad-hoc networks with energy efficiency. We outline the trade-offs that arise by the flexibility of wireless nodes to transmit at different power levels and define a framework for formulating the problem of session routing from the perspective of energy expenditure. A set of heuristics are developed for determining end-to-end unicast paths with sufficient bandwidth and transceiver resources, in which nodes use local information in order to select their transmission power and bandwidth allocation. We propose a set of metrics that associate each link transmission with a cost and consider both the cases of plentiful and limited bandwidth resources, the latter jointly with a set of channel allocation algorithms. Performance is measured through call blocking probability and average energy consumption and our detailed simulation model is used to evaluate the algorithms for a variety of networks.  相似文献   
9.
Solar cooking is often considered “a solution looking for a problem”. Solar cookers have long been presented as an interesting solution to the world's problem of dwindling fuel wood sources and other environmental problems associated with wood fuel demand for cooking. However, recent GTZ field work in South Africa showed different benefits instead: the use of solar cookers resulted in appreciable fuel and time savings as well as increased energy security for households using commercial fuels. These observations are based on field tests in South Africa that started in 1996 to investigate the social acceptability of solar cookers and to facilitate local production and commercialisation of the technology. Impact studies and use rate studies have been carried out by a number of different organisations since the inception of the project and although commercialisation of the technology has not been achieved to its fullest potential, impact studies indicate that solar cookers have a positive development impact on households through fuel-, energy- and time savings. The article aims to summarise the findings of the various studies and present an overview of use rates and impact data. A variety of factors influence solar cooker use rates, which in turn determine impacts. Some factors are related to the user, some to the environment in which the cooker is used and some to the cooker itself. Ultimately, the data shows that on average, only 17% of solar cooker owners do not use their stoves after purchase and that active solar cooker users utilise their stoves on average for 31% of their cooking incidences. Since the majority of solar stove buyers actually use their stoves and obtain real benefits, this suggests that that solar cookers are indeed not a solution looking for a problem but a solution worth promoting.  相似文献   
10.
The structuring of the petrochemical industry has been considered both as a single objective and as a multiobjective problem. Three objective functions have been considered: The maximization of the thermodynamic availability change, the minimization of the lost work and the minimization of the feedstock consumption. The first two objectives aim at structuring the industry for “optimum” energy utilization, while the third aims at the optimum utilization of raw materials. The single objective analysis provided three optimum structures that constitute bounds of the actual performance of the petrochemical industry. The multiobjective analysis on the other hand provides the process designer a set of alternative solutions and subjective criteria have to be used in order to select the “best”.  相似文献   
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