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排序方式: 共有607条查询结果,搜索用时 781 毫秒
61.
高性能IPv6路由器的设计与实现对我国把握下一代互联网发展的先机,保障信息产业的健康和可持续发展具有重要的意义.在分析了高性能IPv6网络驱动子系统的软件结构与实时操作系统VxWorks网络驱动程序模型END的基础上,设计与实现了支持IPv6/v4双协议栈的增强型网络驱动子系统.该驱动子系统能很好地满足高性能IPv6路由器对网络驱动值系统的要求. 相似文献
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63.
Studies on supply chain complexity mainly use the static and dynamic complexity distinction. While static complexity describes the structure of the supply chain, the number and the variety of its components and strengths of interactions between these; the dynamic complexity represents the uncertainty in the supply chain and involves the aspects of time and randomness. This distinction is also valid when classifying the drivers of supply chain complexity according to the way they are generated. Supply chain complexity drivers (e.g., number/variety of suppliers, number/variety of customers, number/variety of interactions, conflicting policies, demand amplification, differing/conflicting/non-synchronized decisions and actions, incompatible IT systems) play a significant and varying role in dealing with complexity of the different types of supply chains (e.g., food, chemical, electronics, automotive). 相似文献
64.
内核安全维系着应用程序的正常运行,而内核错误却仍被周期性地发现,且多数错误是由模块加载机制将存在问题的设备驱动引入内核所致.基于UVM编译器基础架构,提出FPSFI驱动错误运行时隔离机制,使驱动错误隔离机制分解为涉敏函数注册、驱动错误定位与检测函数的插装等三个模块,有效地阻止了由内核API完整性缺失所导致的权限非法提升以及内存空间被多次释放等常见驱动错误.相比于之前的方法,FPSFI将错误分析与定位实现在编译器后端,减少了人工添加检测代码的工作量,而检测函数的单独实现与编译,使得隔离机制对内核接口的依赖程度有所降低.基于Linux平台的测试结果表明,FPSFI能够有效阻止两类典型的驱动错误;FPSFI对后端编译器改动所造成的时间开销比为18.7%;对网络模块的压力测试结果显示,FPSFI不会显著影响CPU利用率以及TCP吞吐量,UDP吞吐量下降17%. 相似文献
65.
The objective of this paper is to describe and interpret the results from a public opinion poll about elderly drivers to provide useful information regarding future challenges related to elderly drivers. The introduction describes demographic developments, factors affecting elderly drivers, crash rates of elderly drivers and characteristics of crashes of elderly drivers. This information is used to provide a context to interpret the results of the public opinion poll. A total of 1238 drivers completed the interview, which required an average of approximately 15 min per respondent. It was administered by telephone to a random sample of Canadian drivers by Opinion Search Inc., in September 2007. Criteria for inclusion were having a valid driver's license and having driven in the past 30 days. Data were weighted according to region, gender and age to avoid bias. Univariate frequency distributions, their 95% confidence intervals and Chi-square statistics were calculated taking account of the stratified and weighted sampling design. Also, multivariate logistic regression was performed, accounting for the design effects of the used sampling design. Lower levels of concern about the issue of elderly drivers were found among the public at large and especially among elderly drivers. While general support for actions to protect elderly drivers was high, elderly drivers were less supportive for a measure requiring them to complete training to maintain their driving privileges. The results from this survey are contrasted against what is known from the literature about the issue of elderly drivers and conclusions regarding future challenges are drawn. 相似文献
66.
As the population of America ages, psychologists will be treating more older adults who are, or are at risk of becoming, impaired drivers. Consequently, psychologists will need to address the issue of driving impairment with many of their patients. Although psychologists should generally respect the autonomy of patients to determine the direction and nature of treatment, their concern for patient and public welfare caused by driving impairments may sometimes override respect for patient autonomy. This article suggests ways to protect patient and public welfare while minimizing the infringement on patient autonomy. Relevant clinical features and a decision making process are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
结合图像调焦系统的实际应用需求,提出一种基于OMAP(Open Multimedia Application Plant)处理器的图像调焦系统方案,给出了处理器与触摸显示屏的接口硬件设计,分析了在Linux系统下的接口驱动开发,讨论了实际应用中存在的图像分辨率变换及触点窗口形成两个关键问题,将输入的图像数据及对焦窗口成比例显示在液晶屏上。在自动选择的对焦窗口不满足要求时,使用触摸屏来重新调整对焦窗口,从而实现人工参与对焦窗口的快速选择及调整,满足了特定领域对图像调焦系统的特殊要求。 相似文献
68.
直流调速系统的双闭环自适应控制 总被引:1,自引:0,他引:1
应用Narendra自适应方案,构造了直流电机的双闭环调速系统。仿真结果表明,该设计方案对于克服因各种因素引起的被控制对象参数的变化所造成系统动态性能的变化具有满意的效果。 相似文献
69.
Johan Stiens Frdric Devisch Maarten Kuijk 《Journal of the Society for Information Display》2002,10(4):375-380
A possible solution for decreasing the ac power dissipation in PMLCD driving is to use an RLC resonant‐drive approach. The achievable power savings depends on several parameters: the LCD material properties, the display size, the frame refresh rate, the driver‐IC technology, etc. A good knowledge of the different parameters is crucial to determining how much power can potentially be saved with resonant driving. In this paper, the influence of these parameters is theoretically derived. Using the essential formulas, a resonant‐driver IC for a 48 × 100 TN‐PMLCD was designed and experimentally verified: a power savings of 45% was obtained. 相似文献
70.
Dorothy J. Begg John D. Langley Rebecca L. Brookland Shanthi Ameratunga Pauline Gulliver 《Accident; analysis and prevention》2014