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21.
设计一种音频设备的上位机控制系统,实现对多台音频设备的集中和远程控制。为了保证上位机在与设备通信的同时,能及时响应前台界面的用户操作,引入了多线程技术。同时,音频设备具有经常被持续、快速调节同一参数的特点,为解决在此情况下由于硬件通信速度有限而导致的设备滞后响应上位机用户操作的问题,设计了一种冗余命令剔除机制。该机制不仅有效地减少了通信占用的资源,而且更好地保证了用户对设备调节控制的实时性。  相似文献   
22.
In this paper we present a word-level model checking method that attempts to speed up safety property checking of industrial netlists. Our aim is to construct an algorithm that allows us to check both bounded and unbounded properties using standard bit-level model checking methods as back-end decision procedures, while incurring minimum runtime penalties for designs that are unsuited to our analysis. We do this by combining modifications of several previously known techniques into a static abstraction algorithm which is guaranteed to produce bit-level netlists that are as small or smaller than the original bitblasted designs. We evaluate our algorithm on several challenging hardware components.  相似文献   
23.
Motorcycle protective clothing can be uncomfortably hot during summer, and this experiment was designed to evaluate the physiological significance of that burden. Twelve males participated in four, 90-min trials (cycling 30 W) across three environments (25, 30, 35 °C [all 40% relative humidity]). Clothing was modified between full and minimal injury protection. Both ensembles were tested at 25 °C, with only the more protective ensemble investigated at 30 and 35 °C. At 35 °C, auditory canal temperature rose at 0.02 °C min?1 (SD 0.005), deviating from all other trials (p < 0.05). The thresholds for moderate (>38.5 °C) and profound hyperthermia (>40.0 °C) were predicted to occur within 105 min (SD 20.6) and 180 min (SD 33.0), respectively. Profound hyperthermia might eventuate in ~10 h at 30 °C, but should not occur at 25 °C. These outcomes demonstrate a need to enhance the heat dissipation capabilities of motorcycle clothing designed for summer use in hot climates, but without compromising impact protection.

Practitioner’s Summary:

Motorcycle protective clothing can be uncomfortably hot during summer. This experiment was designed to evaluate the physiological significance of this burden across climatic states. In the heat, moderate (>38.5 °C) and profound hyperthermia (>40.0 °C) were predicted to occur within 105 and 180 min, respectively.  相似文献   

24.
在目标检测与提取中,传统的蛇模型和基于活动轮廓的局部区域检测方法受到初始条件或者自身的收敛性约束的影响,不仅时间花费多,而且不具备鲁棒性。本文提出一种基于C V模型的变分水平集的目标检测与提取方法,通过大量实验验证,在花费时间和鲁棒性上得到了显著的改善。  相似文献   
25.
Genetic adaptive state estimation   总被引:1,自引:0,他引:1  
A genetic algorithm (GA) uses the principles of evolution, natural selection, and genetics to offer a method for parallel search of complex spaces. This paper describes a GA that can perform on-line adaptive state estimation for linear and nonlinear systems. First, it shows how to construct a genetic adaptive state estimator where a GA evolves the model in a state estimator in real time so that the state estimation error is driven to zero. Next, several examples are used to illustrate the operation and performance of the genetic adaptive state estimator. Its performance is compared to that of the conventional adaptive Luenberger observer for two linear system examples. Next, a genetic adaptive state estimator is used to predict when surge and stall occur in a nonlinear jet engine. Our main conclusion is that the genetic adaptive state estimator has the potential to offer higher performance estimators for nonlinear systems over current methods.  相似文献   
26.
This paper proposes a design methodology for very small databases for the purpose of being hosted by portable devices. Three main differences w.r.t. the traditional design methodologies are introduced: first, the main mobility issues are considered along with data distribution; second, context awareness is included in the data design issues to allow full exploitation of context-sensitive application functionalities; and third, the peculiarities of the storage device  (ss) are taken into account by introducing a logistic phase after the usual conceptual and logical phases. The three aspects together determine the VSDB ambient which is the set of personal and environmental characteristics determining the portion of data that must be stored on the portable device. This paper details the design methodology in its conceptual, logical and logistic phases.  相似文献   
27.
针对军校培养的硕士研究生到基层任职比例逐年增大,为进一步提高研究生培养质量,通过对学院已毕业的硕士研究生在基层部队任职情况的调研,分析了硕士研究生在基层部队任职中暴露出的问题和原因,提出了加强思想政治教育、增强培养的针对性以及与部队开展联合培养等建议.  相似文献   
28.
王启姣 《红水河》2012,31(2):63-65,74
金鸡滩2号机组在运行中出现了油压装置压油泵频繁打油,受油器下游侧端盖与挡油环、端盖与小轴相互碰刮的异常运行情况,文章对此异常情况进行了分析并介绍了故障的排查处理过程,对类似机组的相同故障处理有借鉴作用。  相似文献   
29.
Chen JY  Barnes MJ 《Ergonomics》2012,55(9):1043-1058
A military targeting environment was simulated to examine the effects of an intelligent route-planning agent RoboLeader, which could support dynamic robot re-tasking based on battlefield developments, on the performance of robotics operators. We manipulated the level of assistance (LOAs) provided by RoboLeader as well as the presence of a visualisation tool that provided feedback to the participants on their primary task (target encapsulation) performance. Results showed that the participants' primary task benefited from RoboLeader on all LOAs conditions compared to manual performance; however, visualisation had little effect. Frequent video gamers demonstrated significantly better situation awareness of the mission environment than did infrequent gamers. Those participants with higher spatial ability performed better on a secondary target detection task than did those with lower spatial ability. Finally, participants' workload assessments were significantly lower when they were assisted by RoboLeader than when they performed the target entrapment task manually. Practitioner Summary: This study demonstrated the utility of an intelligent agent for enhancing robotics operators' supervisory control performance as well as reducing their workload during a complex urban scenario involving moving targets. The results furthered the understanding of the interplay among level-of-autonomy, multitasking performance and individual differences in military tasking environments.  相似文献   
30.
以自动化立体仓库的现有设备为基础,提出一些可以提高立体仓库自动化水平的优化措施,在满足正常生产需求的条件下达到了减少仓储储位10%的核心目标.Flexsim仿真模型的运行结果表明:采用优化措施之后比当前运作情况下的单体包仓库最大利用率提高12.36%,多体包仓库平均利用率提高5.32%,整板仓库平均利用率提高1.27%,且工厂对安全存货的需求不受影响.  相似文献   
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