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21.
通信瓶颈下的实时并行任务分配研究   总被引:1,自引:0,他引:1  
提出了实时并行任务粒度划分的具体设计方法,采用了系统内通信迟延最小的约束条件进行多处理器上的任务分配,解决了高速实时信号处理中的数据通信瓶颈问题。在自行设计的超立方体结构的通用信号处理机上,实现了空时二维自适应信号处理和SAR实时成像,显著减小了数据通信迟延,提高了并行效率和性价比。  相似文献   
22.
嵌入式实时操作系统μC/OS-Ⅱ在C8051F020上的移植   总被引:2,自引:0,他引:2  
通过对嵌入式实时操作系统应用背景的分析,论述了在嵌入式控制系统中采用嵌入式实时操作系统的必要性.简略介绍了源代码开放的嵌入式实时操作系统μC/OS-Ⅱ及微控制器C8051F020的特点,重点阐述了μC/OS-Ⅱ在以微控制器C8051F020为运行平台的移植.对μC/OS-Ⅱ的移植条件及各个组成模块进行说明,讨论了移植过程中遇到的问题,并对需要编写的底层硬件的相关函数进行了深入细致的分析,提出了相应的示意性代码.在此基础上,根据实际系统的要求优化改进了原有的任务堆栈结构.  相似文献   
23.
张家桂 《控制与决策》1994,9(6):459-463
本文提出励磁电流可自动控制的他励式双高调速系统设计方案。系统在提升特别是在下放重物时,具有较硬的机械性;在负载10-100%的变化范围内,可实现最大偏差Δnmax/nmin100%≤10%,调速范围D≥10;在满载运行条件下,可节约电能80%以上。  相似文献   
24.
Two important elements in problem solving are the abilities to encode relevant task features and to combine multiple actions to achieve the goal. The authors investigated these 2 elements in a task in which gorillas (Gorilla gorilla) and orangutans (Pongo pygmaeus) had to use a tool to retrieve an out-of-reach reward. Subjects were able to select tools of an appropriate length to reach the reward even when the position of the reward and tools were not simultaneously visible. When presented with tools that were too short to retrieve the reward, subjects were more likely to refuse to use them than when tools were the appropriate length. Subjects were proficient at using tools in sequence to retrieve the reward. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
25.
This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, results revealed strong and negative correlations between relationship conflict, team performance, and team member satisfaction. In contrast to what has been suggested in both academic research and introductory textbooks, however, results also revealed strong and negative (instead of the predicted positive) correlations between task conflict, team performance, and team member satisfaction. As predicted, conflict had stronger negative relations with team performance in highly complex (decision making, project, mixed) than in less complex (production) tasks. Finally, task conflict was less negatively related to team performance when task conflict and relationship conflict were weakly, rather than strongly, correlated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
It has been reported that it is harder to switch to a strong, well-practiced task from a weaker, less-practiced task than vice versa. Three experiments replicated this surprising asymmetry and investigated how it is affected by a reduction in interference between tasks. Experiment 1 progressively delayed the onset of the stimulus attribute associated with the stronger task. Experiments 2 and 3 separated the response sets of the tasks. Both manipulations reduced, without eliminating, interference of the stronger with the weaker task but reversed the asymmetry of switch costs, resulting in a larger cost of switching to the weaker task. The results are interpreted in terms of a model of the interactions between control input, task strength, and task priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
多部件设备维修问题研究及遗传算法求解   总被引:1,自引:0,他引:1  
合理组织设备维修,缩短设备维修时间是生产运营管理的一个重要环节。本文探讨了多部件设备维修的有效组织问题。考虑到维修工人对拆分后设备的不同部分具有不同的维修效率,提出了一种基于维修时间优化的决策方法,将其与经典指派方法进行了比较;进一步地,对这一NP-hard问题设计了遗传算法,通过数值例子讨论了其求解有效性。  相似文献   
28.
炼油化工企业的生产装置是一个连续的、有机的整体,调度生产作业计划是确保生产优化、平稳、有序的基础。先介绍中国国内生产调度计划软件的发展情况,接着论述中国石化股份公司长岭分公司引进AspenTech公司的生产调度系统Aspen Orion及二次开发过程,就其技术与经验以飨同行。  相似文献   
29.
Skill and risk taking are argued to be independent and to require different remedial programs. However, it is possible to contend that skill-based training could be associated with an increase, a decrease, or no change in risk-taking behavior. In 3 experiments, the authors examined the influence of a skill-based training program (hazard perception) on the risk-taking behavior of car drivers (using video-based driving simulations). Experiment 1 demonstrated a decrease in risk taking for novice drivers. In Experiment 2, the authors examined the possibilities that the skills training might operate through either a nonspecific reduction in risk taking or a specific improvement in hazard perception. Evidence supported the latter. These findings were replicated in a more ecological context in Experiment 3, which compared advanced and nonadvanced police drivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
The main purpose of the study reported here was to investigate the relative importance of complexity of syllable structure and task differences in measuring phonological awareness in low-literacy adults. This study is a replication of a study with children conducted by S. A. Stahl and B. A. Murray (1994). Results indicated that the complexity of syllable structure did indeed better describe the construct of phonological awareness in low-literacy adults. At the same time, the authors also found some differences in the pattern of literacy acquisition for their Spanish adults in comparison with child literacy acquisition in English. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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