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排序方式: 共有4153条查询结果,搜索用时 15 毫秒
71.
如今,社会对提高建筑节能效果的呼声越来越高,而且很多时候建筑节能总是伴随着一些高科技材料或设备的应用。本文就针对节能建筑利用玻璃幕墙遮阳技术的应用和作用效果以及玻璃幕墙施工管理需要注意的地方,做了简要探讨。 相似文献
72.
Electric Vehicles (EVs) have been suggested as alternatives to conventional vehicles for reducing petrol consumption and carbon dioxide (CO2) emissions. When a large number of EVs connect to the grid, they can cause a large amount of power loss. Where to install multiple charge stations in the grid, so as to mitigate losses caused by EVs when providing energy to those EVs, is becoming vitally important. In this paper, a distribution test-network model is described. A new analytical method is proposed, using the stations’ cooperation in terms of optimal active and reactive power dispatch as well as power flow analysis for locating the optimal placement of charge stations, so as to reduce power losses. This method is compared with the previously developed current density method for single charge stations using system simulation results. It was demonstrated that the methods proposed in this paper are more accurate than the current density method, and that 17% of the average active power loss can be saved for three different types of load profile. In addition, 27% of the average active power loss was saved by installing two charge stations rather than no charge stations in the test-line. It is shown that this could represent a 2.6% annual yield above inflation for investing in installing and running such charge stations. 相似文献
73.
David Wilcox 《Costume》2014,48(1):21-45
This paper describes the cut and construction of the doublet and hose worn as underdress to the robes and insignia of the Knights of the Most Noble Order of the Garter at the English Court under Charles II. This example belonged to Charles Stuart, sixth Duke of Lennox and third Duke of Richmond (1639–1672), who was created a knight of the Garter in 1661. It is interesting on several counts: the dominant textile is a very pure cloth of silver; the elaborate hose are constructed with reference to earlier seventeenth-century models; the garments exemplify Charles II’s understanding of the importance of ceremony to successful kingship. The suit was conserved for an exhibition at the National Museum of Scotland in Edinburgh and the essay gives some account of discoveries made through this process. In addition, the garments are placed in the context of late seventeenth- century dress. 相似文献
74.
A total of 286 lactic acid bacteria isolated from goat’s dairy products in northwest of Argentina were characterized. Lactobacilli (38%) and cocci (62%) were identified according to morphological, physiological, and relevant technological properties. L. plantarum (14%) and Enterococcus (34%) were the predominant species. S. thermophilus, Pediococcus and L. plantarum were the highest acid producers. Eight strains of L. fermentum produced bacteriocins or metabolites similar to bacteriocins. The API-ZYM test was applied to 39 isolates. Eight strains were selected from their both technological properties and enzymatic activities for use as starter or adjunct culture in the manufacture of artisanal goat cheeses. 相似文献
75.
For several decades, the treatment of central nervous system (CNS) disorders such as, for instance, Alzheimer’s disease (AD), Huntington’s disease (HD), and Parkinson’s disease (PD) represented an important challenge due to the difficulty in delivering drug molecules and imaging agents to the brain. Two strategies have been developed aimed at achieving the efficient delivery of drugs to the brain: invasive (e.g., temporary osmotic Blood Brain Barrier (BBB) opening, direct local delivery of nanoparticles with encapsulated CNS drugs etc.) and noninvasive approaches. As a part of the noninvasive approach among systemic delivery of drug molecules across BBB using nanocarriers, dendrimers represent promising therapeutics agents per se or nanocarriers of CNS drugs and for gene therapies. This original review emphasizes and analyzes the use of dendrimers as promising systems in the treatment of AD and PD, ischemia/reperfusion injury, neuroinflammation including cerebral palsy, neurological injury after cardiac surgery and particularly after hypothermic circulatory arrest, and for retinal degeneration purposes. 相似文献
76.
An integrated technique that embeds civilized swarm optimization (CSO) and Powell’s pattern search (PPS) method is proposed to search economic dispatch of combined heat and power (CHP) dispatch problem. In the proposed technique, CSO is selected as global search technique and PPS is undertaken as a local search technique. Civilized swarm optimization is having attributes of particle swarm optimization (PSO) and society civilization algorithm (SCA). In CSO, mutually interacting societies forms the civilization. The positions of society particles are updated through the guidance of own leader along with their best positions. The best performing particle of CSO is further improved by PPS method based on a certain set criterion. The PPS method is based on the conjugate search direction method and does not require the gradient or Hessian matrix of the function to be optimized. The CHP dispatch problem has a mutual dependency of demand and heat-power capacity of generating units, so it requires an effective constraint handling strategy. In this work, variable reduction strategy with exterior penalty method is applied to satisfy equality constraints. The proposed technique is tested on five CHP test systems considering valve-point loading effect, prohibited operating zones constraint, and transmission losses. The obtained results are compared to the results reported in the literature and found satisfactory. Further, for verification of statistical performance of the proposed technique, t-test and Wilcoxon signed rank test is also performed. 相似文献
77.
78.
《Food Control》2014
During validation and verification of the system for the proper implementation of HACCP principles, it is essential to rely on microbiological data. Considerable science research has been carried out during the last twenty years on sampling and testing of carcasses for hygiene criteria. This includes the preferable indicator microorganisms to be used, in order to indicate the general hygiene of slaughtering procedures, the evaluation of microbiological data gathered and the sampling methods. Furthermore, European Union (EU) and the United States have adopted the procedures for HACCP validation and verification in their legislation. The aim of this review is to demonstrate the relevant modern trends in this field of food science. In conclusion, microbiological data based on the indicators should be interpreted only to assess general trends in the hygiene process of the operator in order to take corrective action. Microbiological results, obtained only at the end of the slaughtering process, do not provide information on the cause of the problem. Therefore, ‘process-based’ microbiological criteria which are based on values measured at various stages of the process, including final carcass values, should be used. Finally, in order to implement an adequate monitoring system, non-destructive techniques of carcass sampling could be used instead of excision. The microbial recovery may be lower, but it is proportional to the excision recovery and therefore, non-destructive techniques, like swabbing with sponges, could be a practical sampling method for the estimation of indicators during the slaughtering procedure and hygiene evaluation. 相似文献
79.
80.
Yung-Ting Chuang 《Telematics and Informatics》2017,34(2):640-656
Education is one of the most important elements in our lives, as it provides a direct gain in knowledge. Thus, in order to provide better academic achievement, more and more instructors are adapting collaborative learning to their classes. However, two major problems lurk behind collaborative learning. First, it is difficult to apply collaborative learning because students tend to engage passively with traditional lectures. As a result, interactive technologies such as clickers have been applied to increase interactive learning and raise the rate of interaction. Nevertheless, these interactive technologies still have some limitations, such as limited mobility, high costs, setup issues, technical difficulties, and little support of higher-order thinking skills. Second, recently there has been an increasing number of EMI (English as Medium of Instruction) courses added to university course offerings in countries where English is not the first language. The goal of these courses is to support university internationalization and address the global status of English. However, it is even harder to achieve in-class interaction in large EMI lecture courses. In addition, some studies argue that EMI courses might affect the overall learning of course content because of students’ poor lecture comprehension and passive engagement in class.In order to address the limitations of interactive technologies, encourage more collaborative learning, facilitate greater in-class interaction in large lecture courses, and resolve students’ poor lecture comprehension in EMI courses, the author introduces MEMIS (Mobile-Supported English-Medium Instruction System), which includes both a T&S (Teachers & Students) mobile app and an EMI pedagogical method. The author first provides detailed implementation and all the features of the T&S mobile app, which improves students’ perceptions of classroom participation and in-class interaction. Then the author explains how she develops her EMI pedagogy such that it utilizes the features of the T&S mobile app to: 1) increase students’ overall learning in her EMI course, 2) develop students’ construction of knowledge and higher-order thinking, and 3) achieve all six cognitive processes from Bloom’s revised taxonomy. The author adapts a quasi-experimental design, statistically analyzes the effectiveness of both exam scores and final grades between a control group and an experimental group, and then asks students to evaluate their experiences and provide feedback about MEMIS. Based on both statistical results and students’ overall feedback, the author confirms that MEMIS is an effective approach that improves lecture comprehension, encourages more class engagement, promotes collaborative learning, and achieves better learning outcomes. 相似文献