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61.
Meinhard von Gerkan Nikolaus Goetze Klaus Lenz Nicole Flores Martin Friedrich Jessica Last Udo Meyer Duc Tran Cong Marcus Bredt 《中国建筑装饰装修》2012,(4):238-239
穿过园林景观来访者可从四个方向进入博物馆。在正方形的建筑体中庭内,一座圆形的挑空大厅将入口层面于其上的三层展览空间连接起来。如同倒置的金字塔般,中庭向上呈阶梯状展开。来访者向外望去,仿佛"漂浮"于主题公园景观之上。盘旋上升的坡道作为极富表现力的空间元素,将人们吸引至建筑顶部,并且实现了展览空间与中庭的视线交流。由于展览空间全部安排在建筑的首层至三层,会议、科研中心,办公空间以 相似文献
62.
A key problem in traffic engineering is the optimization of the flow of vehicles through urban intersections by improving the timing policy of traffic signals. Current methods of signal control policy are based on the junction topography and prespecified static traffic volumes. However, the actual daily traffic volumes can be affected by many time‐dependent factors making a static policy hardly optimal. In this paper, we induce nonstationary predictive models of traffic flow by applying novel methods of time‐series data mining to the traffic sensors data collected from a signalized intersection in Jerusalem over a period of 3 years. Our methodology for modeling dynamic traffic volumes combines clustering and segmentation algorithms. The results of a case study based on real‐world traffic data demonstrate that a dynamic signal policy using the data mining approach can produce a decrease of about 33.7% in the total waiting time of drivers during 1 year, in comparison to the existing static traffic policy. The resulting savings for this junction only would be about 13,800 driving hours, which are worth of about $52,000 per annum in terms of Israeli economy. © 2011 Wiley Periodicals, Inc. 相似文献
63.
Frank B Whitfield T H Ly Nguyen John H Last 《Journal of the science of food and agriculture》1991,54(4):595-604
The effect of relative humidity and chlorophenol content on the fungal conversion of 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol to the corresponding chloroanisoles in fibreboard cartons was studied under temperature and humidity conditions similar to those that could occur in shipping containers during the transportation of packaged dried fruit. The conversion was studied in cartons manufactured from virgin Kraft fibreboard (total chlorophenol content 66 μg kg?1) and fibreboard prepared from recycled waste paper (total chlorophenol content 1375 μg kg?1). Positive correlations were established between both storage humidity and fungal population with chloroanisole production in the fibreboard. The concentration of the chloroanisoles in the packaged fruit increased with increasing relative humidity. The roles of relative humidity and chlorophenol content in fibreboard are discussed with respect to the development of chloroanisole-induced mustiness in packaged dried fruit. 相似文献
64.
A highly sensitive and reproducible liquid chromatography (LC) method for the determination of Amphotericin B in cerebrospinal fluid has been developed and validated. This LC-based method involves using nystatin as an internal standard and solid-phase extraction for sample preparation, followed by reversed-phase separation monitored by absorbance at 410 nm. The method has a limit of quantification of less than 1 ng ml-1 and excellent precision and accuracy, with both percentage relative standard deviation and percentage relative error less than 10%. The established linearity range was 1-10 ng ml-1 (r2 > 0.99). The extraction recovery of Amphotericin B from the cerebrospinal fluid is higher than 90% over the entire linear range. The method has been successfully employed for studying the penetration of Amphotericin B into the central nervous system in dogs and human. 相似文献
65.
We present a molecular dynamics (MD) simulation code for the exploration of extreme multielectron ionization and attosecond–femtosecond electron dynamics in elemental and molecular clusters driven by ultraintense (peak intensity IM = 10 15 –10 16 W cm−2), ultrafast (temporal pulse widths τ = 10–100 fs), near infrared (photon frequency 0.35 fs−1) laser fields. Validity conditions are presented for the applicability of classical MD simulations to high-energy electron dynamics, which rest on the localization of the wave packet and the distinguishability of identical particles. We also examine the cluster size domain for the applicability of the MD simulation code where the laser intensity is uniform inside the cluster. 相似文献
66.
The tryptophan (Trp) biosynthetic pathway leads to the production of many secondary metabolites with diverse functions, and its regulation is predicted to respond to the needs for both protein synthesis and secondary metabolism. We have tested the response of the Trp pathway enzymes and three other amino acid biosynthetic enzymes to starvation for aromatic amino acids, branched-chain amino acids, or methionine. The Trp pathway enzymes and cytosolic glutamine synthetase were induced under all of the amino acid starvation test conditions, whereas methionine synthase and acetolactate synthase were not. The mRNAs for two stress-inducible enzymes unrelated to amino acid biosynthesis and accumulation of the indolic phytoalexin camalexin were also induced by amino acid starvation. These results suggest that regulation of the Trp pathway enzymes under amino acid deprivation conditions is largely a stress response to allow for increased biosynthesis of secondary metabolites. Consistent with this hypothesis, treatments with the oxidative stress-inducing herbicide acifluorfen and the abiotic elicitor alpha-amino butyric acid induced responses similar to those induced by the amino acid starvation treatments. The role of salicylic acid in herbicide-mediated Trp and camalexin induction was investigated. 相似文献
67.
Maimon O. Last M. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》1997,27(1):23-33
A state of a discrete event stochastic system (DESS) can be represented by a tuple of time-varying discrete parameters. The authors have extended the theory of controlled discrete event systems developed by Ramadge, Wonham and other researchers to stochastic modeling and performance measurement. This work presents some important characteristics of the DESS model. The problem of making the most efficient use of information-processing resources (sensors, computer capacity, etc.) in a special class of controlled systems is stated in a new, two-stage format. The format is used to develop a heuristic solution procedure of the problem. Finally, we perform a brief discussion of the model applicability to real-life design of automatic supervisors 相似文献
68.
RJ Prineas K Goodman CL Soskolne G Buck M Feinleib J Last JS Andrews 《Canadian Metallurgical Quarterly》1998,8(8):482-489
PURPOSE: A survey to establish both the need and subject areas for a possible new set of ethics guidelines for epidemiologists was conducted among a random sample of 300 North American (Canada, Mexico, and United States) members of three major United States-based professional epidemiology organizations. METHODS: An 88% response rate revealed wide agreement on topics to be included in any new set of guidelines, but uncertainty prevailed about the need for new guidelines; 41% agreed that there was a need to develop a new set, 43% had no opinion, and 16% disagreed. RESULTS: There was almost no difference in preferences between men and women for topics to be included in a new set of guidelines, or between those aware or unaware of extant ethics guidelines in epidemiology. Fifty-four percent were aware of such guidelines and only 29% of these said they could describe the content of the guidelines. CONCLUSION: More needs to be done to evaluate the utility of ethics codes in epidemiology. 相似文献
69.
In this paper, the new method of measurements is presented for the technological control of the lithographic fabrication of high aspect ratio microstructures with complex side-wall profiles. The sampling procedure includes pouring polymer glue on a substrate with the microstructures and its hardening, sectioning the polymer matrix in the depth with planes parallel to the substrate and analysis of digital optical microscope images of the planes. The measured deviations the micro structure profiles in comparison with the designed geometry are used for the further optimization of the technological design of planar X-ray refractive lenses. 相似文献
70.
Since its inception in 1957 the BMA's annual film competition has fulfilled three roles--promoting the effective use of film and video in medical education, encouraging the production of high quality audiovisual material, and helping to increase the holdings of its film library. The BMA awards recognise programmes for their clinical accuracy, educational value and creative use of the medium. 相似文献