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排序方式: 共有400条查询结果,搜索用时 15 毫秒
81.
82.
Carl Gunther Bauer 《世界建筑导报》2010,25(1)
项目地点:博茨瓦纳吉瓦宁项目类型:其他开工日期:2006年8月该项目获2005年豪瑞可持续建筑大奖赛非洲中东地区提名奖 相似文献
83.
This paper addresses the issues of post-measurement processing of data collected in a power quality assessment study. Three broad types of post-measurement processing objectives are considered: to enhance accuracy; to estimate data; and to reduce the volume of the collected data. The methods used to enhance accuracy are bad data identification and rejection. Averaging is discussed as a method to “filter” measurement error. The methods used for data estimation are state estimation techniques in both the time and frequency domain. The methods used to reduce the volume of the collected data are based on the calculation of marginal and conditional probabilities and expectations. The integrated use of these techniques in an instrumentation system for power quality assessment is discussed. The main suggested application is for the measurement of harmonics 相似文献
84.
85.
FM Uckun Y Yanishevski N Tumer B Waurzyniak Y Messinger LM Chelstrom EA Lisowski O Ek T Zeren H Wendorf MC Langlie JD Irvin DE Myers GB Fuller W Evans R Gunther 《Canadian Metallurgical Quarterly》1997,3(3):325-337
Withdrawal responses to mechanical and thermal stimuli applied to the plantar surface of the hindpaw were measured before and after bone damage. In separate groups of rats the bone was injured by scraping the periosteum of the tibia, drilling a hole through the tibia, aspirating bone marrow, or drilling a hole through the calcaneus. Scraping the periosteum did not alter withdrawal responses to the mechanical stimuli, or evoke nocifensive behavior. In contrast, secondary mechanical hyperalgesia and allodynia, and cold allodynia were observed after a hole was drilled through the tibia or calcaneus and after aspiration of bone marrow. The secondary hyperalgesia peaked at 2 h after injury. Drilling a hole through the calcaneus permitted primary hyperalgesia to be easily quantified. Primary hyperalgesia lasted up to 24 h after injury. Nocifensive behavior characterized by a lifting and guarding of the damaged limb was also observed after a hole was drilled through the tibia or calcaneus. Drilling a hole through the tibia or calcaneus should be a useful experimental model for investigating the mechanisms underlying bone pain. 相似文献
86.
A recent meta-analysis of alcohol treatment outcome research concluded that educational lectures and films are an ineffective treatment modality in the treatment of persons with alcohol-related problems. This paper suggests several reasons why educational lectures and films are likely to be ineffective with alcohol misusers. Possible explanations include (a) the inability of alcoholics to appreciate and utilize (presented) information because of the cognitive deficits associated with chronic alcohol misuse, (b) the presentation of inaccurate or misleading information about alcoholism through lectures and films (i.e., unitary disease concept, faulty conceptualizations of denial), and (c) conventional alcoholism education which may undermine an individual's belief in her/his ability to make a complete and successful recovery from chemical dependence. Treatment implications and suggestions for further research are briefly discussed. 相似文献
87.
Danny De Schreye Bern Martens Gunther Sablon Maurice Bruynooghe 《Journal of Automated Reasoning》1991,7(3):337-358
We present a technique for the compilation of bottom-up and mixed logic derivations into PROLOG-programs. It is obtained as an extension of a program transformation technique called Compiling Control. We illustrate its applications in three different domains: solving numerical problems, integrity checking in deductive databases and theorem proving. The aim is to obtain efficient PROLOG programs for problems in which a non-top-down control is most appropriate.Work partly supported by ESPRIT BRA COMPULOG (project 3012).Supported by the Belgian I.W.O.N.L.-I.R.S.I.A. under contract number 5203. Author for correspondence.Supported by the Belgian National Fund for Scientific Research. 相似文献
88.
A leaner version of traditional capacity planning can help one hones system performance without inflating schedules or delaying time to market. It provides an approach to assessing application scalability that matches management requirement to keep a tight rein on project schedules. 相似文献
89.
A self-referencing technique compensating for fiber losses and source fluctuations in reflective air-gap intensity-based optical fiber sensors is described. A dielectric multilayer short-wave-pass filter is fabricated onto or attached to the output end face of the lead-in-lead-out multimode fiber. The incoming broadband light from a white light or a light-emitting diode is partially reflected at the filter. The transmitted light through the filter projects onto a mirror. The light returning from the reflecting mirror is recoupled into the lead-in-lead-out fiber. These two reflections from the filter and the reflecting mirror are spectrally separated at the detector end. The power ratio of these two reflections is insensitive to source fluctuations and fiber-bending loss. However, because the second optical signal depends on the air-gap separation between the end face of the lead-in-lead-out fiber and the reflecting mirror, the ratio provides the information on the air-gap length. A resolution of 0.13 μm has been obtained over a microdisplacement measurement range of 0-254 μm. The sensor is shown to be insensitive to both fiber-bending losses and variations in source power. Based on this approach, a fiber-strain sensor was fabricated with a multilayer interference filter directly fabricated on the end face of the fiber. A resolution of 13.4 microstrain was obtained over a measurement range of 0-20,000 microstrain with a gauge length of 10 mm. The split-spectrum method is also incorporated into a diaphragm displacement-based pressure sensor with a demonstrated resolution of 450 Pa over a measurement range of 0-0.8 MPa. 相似文献
90.
Dieter Wittmann Rainer Radtke Jochen Zeil Gunther Lübke Wittko Francke 《Journal of chemical ecology》1990,16(2):631-641
The nest of the stingless bee,Trigona (Tetragonisca) angustula, is guarded by bees positioned in the nest entrance and others hovering in front of it. Hovering guard bees track returning foragers sideways along the last 10 cm in front of the nest, but intercept and incapacitate nest intruders by clinging with mandibles to wings and legs. When attacked by the cleptobiotic stingless beeLestrimelitta limao, the colony strengthens its aerial defense with hundreds of additional hoverers. To test our hypothesis that this reaction is due to interspecific chemical communication based on kairomone effects, we presented synthetic cephalic volatiles of both species at the nest entrance and counted the number of bees leaving the nest and taking up hovering positions. We conclude that guard bees recognizeL. limao by the major terpenoids of their volatile cephalic secretions, geranial, neral (=citral) and 6-methyl-5-hepten-2-one; other components may fine-tune this recognition. The effect of chemical stimuli is not significantly enhanced by combination with a dummy ofL. limao. Guard bees, we hypothesize, respond to this kairomone by secreting a species specific alarm pheromone; a major component of this pheromone, benzaldehyde, recruits additional bees to defend the nest. 相似文献