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181.
S. Kidane L. Alexander R. Rajamani P. Starr M. Donath 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2008,46(4):295-322
One way of addressing traffic congestion is by efficiently utilizing the existing highway infrastructure. Narrow tilting vehicles that need a reduced width lane can be part of the solution if they can be designed to be safe, stable, and easy to operate. In this paper, a control system that stabilizes the tilt mode of such a vehicle without affecting the handling of the vehicle is proposed. This control system is a combination of two different types of control schemes known as steering tilt control (STC) and direct tilt control (DTC) systems. First, different existing variations of both STC and DTC systems are considered and their shortcomings analysed. Modified control schemes are then suggested to overcome the deficiencies. Then a new method of integrating these two control schemes that guarantees smooth switchover between the controllers as a function of vehicle velocity is proposed. The performance of the proposed STC, DTC, and integrated systems is evaluated by carrying out simulations for different operating conditions and some experimental work. The design of a second-generation narrow tilting vehicle on which the developed control system has been implemented is presented. 相似文献
182.
基于图论的列车运行径路分析与构造 总被引:2,自引:1,他引:1
采用图论及系统结构的分析方法,提出列车运行径路的表达、组织方法和列车运行径路的构造原理,方法。从而效清晰全面地表面路局列车运行径路,并使数据冗余尽可能的少。 相似文献
183.
周丽 《上海交通大学学报(哲学社会科学版)》2000,8(1):89-91,110
本文对企业研究与开发费用的现行会计处理方法,即全部费用化和部分资本化作了分析,并指出了这两种处理方法存在的缺点。提出了在知识经济时代,随着企业研究开发费用投入的不断增加,对研究开发费用的会计处理应采用全部资本化处理方法的观点。 相似文献
184.
THE CHARACTERISTICS OF ENDOGENOUS OUABAIN SECRETIONFROM CULTURED BOVINE ADRENOCORTICAL CELLS 总被引:2,自引:0,他引:2
Lü Zhuoren 《西安交通大学学报(英文版)》2000,12(1):31-33,49
Endogenousouabain(Eo)hasbeenconsideredasacirculatingfactorthatregulatesthebodyfluidvolumebalance,urinesodiumextractionandvaso-contrictivetone,whichplaysanimportantroleinpathogenesisofhypertensionandsomecardiovas-culardisorderst12.Sinceitwasdiscoveredandiden-tifiedbyHamlynin199lt,i,severallinesofevi-dencesindicatethattheadrenalcortexisthemajorsourceofEO.Thepurposeofthisstudyistocom-parethecharacteristicsofEOsecretionwiththewell-knownadrenocorticalhormonesaldosteroneandcortisol,determinetheeff… 相似文献
185.
Lü Yi 《西安交通大学学报(英文版)》2000,12(1):50-54,57
Thebileacidswereconfirmedasnonspecificcytotoxicsubstanceswhichplayveryimportantro1einpathophysiologyofextrahepaticcholesta-sis[la.Invitrostudieshadprovedthatthebileacidscouldcausechronicandacuteinjuryofpancreaticductalepitheliumactingasaninitiatorofpancre-atitist2i.Thepancreaticcancerisamajorworld-widepublichealthproblernandremainsasignifi-cantclinica1challenge.Atthetimeofdiagnosis,about7o%ofpancreaticcancerpatientsmanifestobstructivejaundicewhichcanresultinprogressiveliverdysfunctionandculmin… 相似文献
186.
As a means of transportation and as a form of physical activity, bicycling generates benefits to the bicyclist as well as
to the community as a whole. Bicycling now accounts for less than 1 percent of all trips for all purposes in the U.S., but
evidence from other western countries suggests that under the right conditions, bicycling levels can be significantly higher.
Indeed, the experiences of some U.S. cities suggest that it is possible to create conditions conducive to higher levels of
bicycling even in the U.S. However, the extent to which bicycle investments have contributed to bicycling levels in these
communities has not been rigorously assessed. The purpose of this study is to provide a better understanding of the determinants
of bicycle ownership and use as a basis for identifying ways to promote bicycling. A cross-sectional study of six cities was
designed to test the importance of bicycle infrastructure and other physical environment factors relative to individual factors
and social environment factors, using a nested logit model to examine ownership and use decisions jointly. The results show
strong effects of individual attitudes and physical and social environment factors on bicycle ownership and use. 相似文献
187.
Shore-based ship assistance is a topic that increasingly is attracting attention from the maritime community. Subjects such as shore-based pilotage and VTS are often discussed and there is technological and political pressure towards more extensive forms of such assistance. Perhaps less often mentioned, but not less important, is the human side of these subjects. The present paper examines two of the central concerns for the people who actually work within today’s VTS centers, namely communication and trust. The study consisted of a literature review, study visits, observations and interviews. Communication and trust are found to be closely related, and one main finding is that adapting one’s means of communication to the context can be a very powerful (and necessary) tool for the creation of trust. Another important result is that the ability of the shore-based operator to see the situation from the viewpoint of the crew is crucial for the creation and maintenance of trust. 相似文献
188.
189.
本文介绍了我院应用AM12(AVEVA Marine 12)软件进行海洋工程设计的背景及使用情况,分析了现有的电气建模方式与方法,并着重讨论了自主完成的电气建模优化方法与AM12软件电气设计相关的二次开发情况。 相似文献
190.
汽车动力总成三点式悬置系统的设计方法探讨 总被引:4,自引:1,他引:3
首先分析汽车动力总成一悬置系统的振动激励、质量矩阵、刚度矩阵各元素的特点及其相互关系,阐释了系统弹性解耦设计的理论基础和重要性。然后根据动力总成一悬置系统刚度矩阵各元素的解析表达式,应用V形悬置组的弹性解耦原理,论述了目前普遍应用的三点式悬置系统在弹性解耦设计方面的问题,提出了悬置布置设计匹配的有效方法。 相似文献