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排序方式: 共有5381条查询结果,搜索用时 343 毫秒
1.
针对云计算应用于无线传感器网络(Wireless Sensor Network,WSN)时延敏感型业务时存在的高传输时延问题,提出了一种WSN低功耗低时延路径式协同计算方法。该方法基于一种云雾网络架构开展研究,该架构利用汇聚节点组成雾计算层;在数据传输过程中基于雾计算层的计算能力分步骤完成任务计算,降低任务处理时延;由于汇聚节点计算能力较弱,时延降低将导致能耗增加,WSN工作寿命减短,为此提出能耗约束下的任务映射策略,并利用离散二进制粒子群优化(Binary Particle Swarm Optimization,BPSO)算法解决能耗约束下的时延优化问题。仿真结果表明,在相同的能耗约束下,对比其他算法,基于BPSO算法得出的映射方案能有效降低业务处理时延,满足时延敏感型业务的需求。 相似文献
2.
Alawiya Reslan Juliano G. Haddad Liadrine Moukendza Koundi Philippe Desprs Jean-Loup Bascands Gilles Gadea 《International journal of molecular sciences》2021,22(5)
Mosquito-borne Zika virus (ZIKV) became a real threat to human health due to the lack of vaccine and effective antiviral treatment. The virus has recently been responsible for a global outbreak leading to millions of infected cases. ZIKV complications were highlighted in adults with Guillain–Barré syndrome and in newborns with increasing numbers of congenital disorders ranging from mild developmental delays to fatal conditions. The ability of ZIKV to establish a long-term infection in diverse organs including the kidneys has been recently documented but the consequences of such a viral infection are still debated. Our study aimed to determine whether the efficiency of ZIKV growth in kidney cells relates to glucose concentration. Human kidney HK-2 cells were infected with different ZIKV strains in presence of normal and high glucose concentrations. Virological assays showed a decrease in viral replication without modifying entry steps (viral binding, internalization, fusion) under high glucose conditions. This decrease replication was associated with a lower virus progeny and increased cell viability when compared to ZIKV-infected HK-2 cells in normal glucose concentration. In conclusion, we showed for the first time that an elevated glucose level influences ZIKV replication level with an effect on kidney cell survival. 相似文献
3.
Journal of Computer Science and Technology - DOACROSS loops are significant parts in many important scientific and engineering applications, which are generally exploited pipeline/wave-front... 相似文献
4.
Evidence suggests that transient visual information, such as animations, may be more challenging to learn than static visualizations. However, when a procedural-manipulative task is involved, our evolved embodied cognition seems to reverse this transitory challenge. Hence, for object manipulative tasks, instructional animations may be more suitable than statics. We investigated this argument further by comparing animations with statics using a Lego task shown to university students, by examining three potential moderators of effectiveness: (a) the environment of manipulation (virtual or physical), (b) the quality of visual information (focused or unfocused), and (c) the presence of hands (no hands or with hands). In Experiment 1 we found an advantage of animation over statics, and no differences among the environments. In Experiment 2, we again observed an animation advantage, a small advantage of focused static information compared to unfocused static information, and a positive effect of not showing the hands. 相似文献
5.
嵌入式RTOS中任务优先级反转问题研究 总被引:1,自引:0,他引:1
针对嵌入式实时系统任务调度策略的特点,任务在运行的时候可能被更高优先级的任务中断。分析了嵌入式RTOS中的最高就绪任务的查找算法,指出该调度算法存在的不同优先级的反转问题,并且针对这一问题进行研究,给出了相应的优先级继承方案。较好地解决了RTOS中任务调度中的优先级的反转问题。 相似文献
6.
A real-time distributed database system (RTDDBS) must maintain the consistency constraints of objects and must also guarantee
the time constraints imposed by each request arriving at the system. Such a time constraint of a request is usually defined
as a deadline period, which means that the request must be serviced on or before its time constraint. Servicing these requests
may incur I/O costs, control-message transferring costs or data-message transferring costs. As a result, in our work, we first
present a mathematical model that considers all these costs. Using this cost model, our objective is to service all the requests
on or before their respective deadline periods and minimize the total servicing cost. To this end, from theoretical standpoint, we design
a dynamic object replication algorithm, referred to as Real-time distributed dynamic Window Mechanism (RDDWM), that adapts to the random patterns of read-write requests. Using competitive analysis, from practical perspective,
we study the performance of RDDWM algorithm under two different extreme conditions, i.e., when the deadline period of each
request is sufficiently long and when the deadline period of each request is very short. Several illustrative examples are
provided for the ease of understanding.
Recommended by: Ashfaq Khokhar 相似文献
7.
介绍了文档数据库Lotus Domino/Notes的特点.对其文档处理的核心,即Notes文档的ID构成机制作了系统剖析.并在此基础上分析了如何在文档复制中运用ID的不同组件以及如何运用API程序访问文档ID等。 相似文献
8.
介绍了一种日常参数智能控制器的研制及研制过程中的几个重要问题的解决方法。特别是用于城市照明及美化城市的彩灯的开、关时间智能控制方面,给出了依据当地绝对时间、经度、纬度进行昼夜时间计算的方法,使之在不接光电传感器情况下可跟踪季节的昼夜变化。控制系统采用89C2051单片机,配有时钟日历芯片DS12887,系统体积小、功能强、可靠性高。 相似文献
9.
分析了河北冶金近期行业发展特别关注的几个问题:钢铁生产发展过快;产业结构缺陷,资源供应和环境压力。同时,文章从分析国内外市场形势和国家宏观政策形势入手,提出了河北冶金工业对产品结构调整,工艺装备调整和组织结构调整的必要性,任务和需注意的问题。 相似文献
10.
McIntyre Christa K.; Marriott Lisa K.; Gold Paul E. 《Canadian Metallurgical Quarterly》2003,117(2):320
The present experiment examined the relationship between release of acetylcholine (ACh) in the amygdala and performance on a hippocampus-dependent spatial working memory task. Using in vivo microdialysis, the authors measured ACh release in rats during testing on a spontaneous alternation task. Amygdala ACh release was positively correlated with performance on the hippocampus-dependent task. These findings suggest that activation of the amygdala promotes processing in other neural systems important for learning and memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献