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41.
通过对嵌入式系统定义及嵌入式技术特点的阐述,说明了ARM嵌入式技术的优势。结合嵌入式技术在虫害测报系统中的具体应用实例,说明了运用ARM嵌入式系统的必要性、有效性以及必然趋势。  相似文献   
42.
针对高校科研能力评估过程中存在的多因素、高非线性特点,经典评估模型主观性较强,导致模型评估准确性不高的问题,提出基于协同智能水滴算法IWD和粗糙集块神经网络RBNN的高校科研能力评估模型。首先,引入智能水滴算法,并针对传统智能水滴算法固定旁域搜索范围不利于提升算法搜索效率的问题,提出一种局部空间自动缩放算法LSAS,该算法根据当前种群最优个体,自动调整下一步搜索空间大小,对进化过程进行指导,提高算法的进化效率;其次,基于粗糙集理论对高校科研能力数据进行特征预处理,简化数据计算量;最后,对块神经网络和粗糙集参数进行编码,并对高校科研能力模型进行评估。仿真结果表明,此评估模型具有较高的准确性和较快的计算效率。  相似文献   
43.
Charging coordination of large‐population autonomous plug‐in electric vehicles (PEVs) in the power grid can be formulated as a class of constrained optimization problems. To overcome the computational complexity, a game‐based method is proposed for the charging problems of the PEV population, which is composed of homogeneous subpopulations, such that individuals update their best charging strategies simultaneously with respect to a common electricity price determined by the total demand. To mitigate the oscillation behavior caused by the greedy behavior for the cheap electricity by individuals, a deviation cost is introduced to penalize against the deviation of the individual strategy from the average value of the homogeneous subpopulation. By adopting a proper deviation cost and following a best strategy update mechanism, the game systems may converge to the socially optimal valley‐fill Nash equilibrium. Simulation examples are studied to illustrate the results.  相似文献   
44.
与Native应用相比,移动web应用能很好地解决目前Native操作系统割裂的问题,将为产业链各方带来全新的平等竞争机会,引导移动互联网产业链的新模式发展。本文首先介绍了HTML5移动web应用的发展概况,然后分析了基于HTML5移动web应用相关技术标准的发展情况,随后对基于HTML5的移动web应用及终端的技术实现方案进行了分析,最后对全文内容进行了总结,从HTML5移动web应用、技术标准及终端的发展趋势进行了展望。  相似文献   
45.
针对在C++程序设计课程教学中存在的问题,结合对自主-合作教学模式的研究,提出以自主学习教学模式贯穿教学始终;案例驱动的精讲与泛读相结合;手写程序与机器调试相结合;自主学习与合作学习相结合的教学新思路。并阐述了上述方法在教学改革实践中的具体应用及效果。  相似文献   
46.
对开源无线传感器网络操作系统MansOS体系结构、核心技术及关键特性进行了分析,与TinyOS、Contiki、Mantis等无线传感器网络操作系统进行了对比研究,阐述了MansOS应用开发所涉及的开发环境构建、程序设计、调试与测试等技术,供应用和研究MansOS作参考.  相似文献   
47.
本文介绍了实时内核的中断机制,研究了μC/OS-III为缩短中断关闭时间做出的改进。通过对比μc/OS—II以及μC/OS—III的中断管理办法,分析μC/OS—III在哪些方面作出了改进。这些改进使得μC/OS—III的实时性能得到显著提升,使得μC/OS—III的中断关闭时间大大缩短。  相似文献   
48.
ABSTRACT

Information technology organizations within most corporations are spending significant time and resources securing IT infrastructure. This increased need for security is driven by a number of factors. These factors include increased dependency on the Internet, financial and legal liability, protection of personal identity information and sensitive corporate data, increased numbers and age of legacy systems with limited vendor support, deploying complex systems, and new regulations governing corporate transactions. There a number of technologies on the market today that can mitigate most of these security factors. However, managers in IT organizations need to identify potential future threats and security technologies to assess and potentially mitigate risk through the deployment of those technologies. This article investigates three areas critical to the successful deployment and securing of information technology.  相似文献   
49.
In commercial networks, user nodes operating on batteries are assumed to be selfish to consume their resources (i.e., bandwidth and power) solely maximizing their own benefits (e.g., the received signal-to-noise ratios (SNRs) and datarates). In this paper, a cooperative game theoretical framework is proposed to jointly perform the bandwidth and power allocation for selfish cooperative relay networks. To ensure a fair and efficient resource sharing between two selfish user nodes, we assume that either node can act as a source as well as a potential relay for each other and either node is willing to seek cooperative relaying only if the datarate achieved through cooperation is not lower than that achieved through noncooperation (i.e., direct transmission) by consuming the same amount of bandwidth and power resource. Define the cooperative strategy of a node as the number of bandwidth and power that it is willing to contribute for relaying purpose. The two node joint bandwidth and power allocation (JBPA) problem can then be formulated as a cooperative game. Since the Nash bargaining solution (NBS) to the JBPA game (JBPAG) is computationally difficult to obtain, we divide it into two subgames, i.e., the bandwidth allocation game (BAG) and the power allocation game (PAG). We prove that both the subgames have unique NBS. And then the suboptimal NBS to the JBPAG can be achieved by solving the BAG and PAG sequentially. Simulation results show that the proposed cooperative game scheme is efficient in that the performance loss of the NBS result to that of the maximal overall data-rate scheme is small while the maximal-rate scheme is unfair. The simulation results also show that the NBS result is fair in that both nodes could experience better performance than they work independently and the degree of cooperation of a node only depends on how much contribution its partner can make to improve its own performance.  相似文献   
50.
The opportunistic cooperation schemes,where only the "best" relay is selected to forward the message,have been widely investigated recently for their good performance in terms of outage probability.However,the unfair selections of relays may cause unbalance power consumptions among relays,which reduces the lifetime of energy constrained networks.In this paper,we introduce a novel concept of outage priority based fairness(OPF),aiming at improving the selection fairness among relays appropriately without outage performance deterioration.Then,a cooperation scheme is proposed to meet this concept,and corresponding theoretical analysis is also provided.Afterward,based on OPF,the achievable upper bound of the fairness is derived,and an optimal cross-layer designed scheme is also provided to achieve the bound.Numerical simulations are carried out finally,which not only validate the theoretical analysis,but also show that taking advantages of the proposed schemes,the fairness among all relays,as well as the network lifetime,can be greatly improved without any loss of outage performance,especially in high SNR regime.  相似文献   
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