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51.
Nikonovas A Harrison AJ Hoult S Sammut D 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2004,218(2):121-126
Most attempts to measure forces developed by the human hand have been implemented by placing force sensors on the object of interaction. Other researchers have placed sensors just on the subject's fingertips. In this paper, a system is described that measures forces over the entire hand using thin-film sensors and associated electronics. This system was developed by the authors and is able to obtain force readings from up to 60 thin-film sensors at rates of up to 400 samples/s per sensor. The sensors can be placed anywhere on the palm and/or fingers of the hand. The sensor readings, together with a video stream containing information about hand posture, are logged into a portable computer using a multiplexer, analogue-to-digital converter and software developed for the purpose. The system has been successfully used to measure forces involved in a range of everyday tasks such as driving a vehicle, lifting saucepans and hitting a golf ball. In the latter case, results are compared with those from an instrumented golf club. Future applications include the assessment of hand strength following disease, trauma or surgery, and to enable quantitative ergonomic investigations. 相似文献
52.
Due to natural or man-made disasters, the evacuation of a whole region or city may become necessary. Apart from private traffic, the emergency services also need to consider transit-dependent evacuees which have to be transported from collection points to secure shelters outside the endangered region with the help of a bus fleet. We consider a simplified version of the arising bus evacuation problem (BEP), which is a vehicle scheduling problem that aims at minimizing the network clearance time, i.e., the time needed until the last person is brought to safety. In this paper, we consider an adjustable robust formulation without recourse for the BEP, the robust bus evacuation problem (RBEP), in which the exact numbers of evacuees are not known in advance. Instead, a set of likely scenarios is known. After some reckoning time, this uncertainty is eliminated and planners are given exact figures. The problem is to decide for each bus, if it is better to send it right away—using uncertain information on the evacuees—or to wait until the the scenario becomes known. We present a mixed-integer linear programming formulation for the RBEP and discuss solution approaches; in particular, we present a tabu search framework for finding heuristic solutions of acceptable quality within short computation time. In computational experiments using both randomly generated instances and the real-world scenario of evacuating the city of Kaiserslautern, Germany, we compare our solution approaches. 相似文献
53.
A general theory of thin-wire multiturn loop antennas is presented. For convenience the windings of the loop are considered to form a circular helix. An integral equation is derived and solved numerically for the current distribution on the antenna. The antenna impedance, efficiency, and pattern are obtained. 相似文献
54.
The letter reports an alternative approach to the realisation of long, low-attenuation, high-strength single-mode optical fibres suitable for high bit-rate transmission over long distances in adverse environments. We show that low attenuation (less than 0.45 dB km) can be achieved in combination with high proof-test levels (1% ? 2% strain) in fibre lengths greater than 5 km, using natural fused-quartz tubing, and report a 15 km fibre having an attenuation of 0.44 dB km which survived a proof test at 1% strain. 相似文献
55.
Bob Scannell 《电子与电脑》2011,(4)
精密的工业制程对于马达与相关机械有效而且一致性运作的依赖日益提高.在机械中的失衡、缺陷、松散、以及其它异常现象通常都会转换成振动,而接着就是失去精密度与安全性的考虑.假如不加以处理的话,除了性能与安全的问题之外,当设备需要脱机修理时,生产力的损失将会变得无可避免. 相似文献
56.
Straits-Tr?ster Kristy A.; Brancu Mira; Goodale Bob; Pacelli Sheryl; Wilmer Charlotte; Simmons Erin M.; Kudler Harold 《Canadian Metallurgical Quarterly》2011,3(3):283
Meeting the mental health needs of Veterans returning from recent deployment requires the coordinated effort of partnerships across Department of Defense (DoD), Department of Veterans Affairs (VA), and state and local communities. Although the proportion of Veterans of Iraq and Afghanistan who have accessed VA health care has grown, the majority of these new combat Veterans have yet to present for VA care. The stigma associated with reporting a deployment-related mental health problem may be one factor in this, but access to treatment may also be an important concern among the one third of American Veterans who live in rural or highly rural areas. As these Veterans are more likely to present to a primary care, faith-based or mental health provider in their own community, partnerships between community providers, DoD, and VA are of critical importance in ensuring appropriate care, regardless of treatment setting. In an effort to improve services and access to services, especially to rural Veterans, an educational public health initiative was created to educate community providers about military culture, deployment-related mental health issues, VA resources, and evidence-based treatments. We describe the development, dissemination and evaluation of this initiative, as well as lessons learned for future similar endeavors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
57.
2,1,3‐Benzothiadiazole‐5,6‐Dicarboxylic Imide – A Versatile Building Block for Additive‐ and Annealing‐Free Processing of Organic Solar Cells with Efficiencies Exceeding 8% 下载免费PDF全文
58.
59.
Bob Hiebert 《电子产品世界》2006,(1):67
实时频谱分析正在多种应用中得到运用,从锁相环和压控振荡器等部件一直到电路板和系统.随着RF渗透到万物之中,部件的开发者们将需要从他们的PL上和VCO中找出尖峰或者毛刺,而且还需要确保器件在电路板级参考设计中能正常工作.RF(射频)除了无所不在之外,在本质上还是一种瞬态过程,因此便带来对实时频谱分析工具的需求. 相似文献
60.
综述了能促进消费者健康和社会安宁的纺织品的最新的技术发展.介绍了种种创新的纺织品.社会的变革和发展趋势愈来愈强调生活环境、休闲娱乐、通信以及交通等的健康与安宁的重要性.最近的技术发展增加了使纺织品获得新性能的可能性,并直接关系到使用者的健康和生活环境.纺织品作为一种柔性材料,具有悬垂性好、弹性好、易变形、强度较高、较好的染色吸附性以及其他后处理特性,可以由多种原料制成,并具有多种功能. 相似文献