RFID读写器功率的自适应调节策略

射频识别(RFID)读写器一般以恒定功率工作,会导致电能的不必要消耗。针对该问题,提出一种基于模糊控制理论的RFID读写器功率自适应调节策略,在前后2次读取RFID标签数差值的基础上,采用相应模糊控制算法动态改变RFID读写器的输出功率,从而优化输出。仿真测试结果表明,该策略能明显降低读写器的能耗。     

带可变事故切除时间的暂态稳定约束最优潮流计算

在暂态稳定约束最优潮流（OTS）研究的基础上,提出了电力系统事故切除时间为变量的暂态稳定约束最优潮流（OPF-TSCC）模型.根据约束转换方法,建立了OPF-TSCC对应的一类广义半无限优化（GSIP）;基于GSIP现有理论和算法,提出了求解GSIP的一类新算法.电力系统数值仿真结果验证了所提出的模型和算法的有效性.新模型还可用于求解系统故障的临界切除时间（CCT）.     

基于类别分布差异和特征熵的维吾尔语文本特征选择

文本特征选择是在文本自动分类中最重要的一个环节。为了更好地解决维吾尔文文本分类中特征空间的高维性和文档表示向量的稀疏性问题, 提出一种基于特征的类别分布差异和信息熵的维吾尔文文本特征选择方法。该方法不仅要考虑特征在类别间的分布情况, 而且也要考虑特征在类别内的分布情况。采用本方法对维吾尔文文本语料进行了分类实验, 并与一些传统的特征选择方法进行了比较。从结果来看, 本方法在所选特征数更少的情况下, 达到了比其他方法更高的分类MacroF1值853%, 比传统的IG和CHI等方法在MacroF1值上分别高出了43%和61%。     

Effects of virtual presence and learning outcome using low-end virtual reality systems

Low-cost technology is essential to integrate Virtual Reality (VR) into educative institutions around the world. However, low-cost technology usually refers to low-end technology, which may compromise the level of immersion of the VR system. This study evaluates whether low-end and high-end VR systems achieve a comparable learning outcome regardless their immersion level. We also analyze the relationship between virtual presence and the learning outcome arising from a VR educational experience. An evaluation with 42 participants was conducted. We measured learning outcome and virtual presence under three different configurations, namely: a desktop computer, a low-end VR system, and a high-end VR system. The impact of simulator sickness was also analyzed. Results revealed a lower learning outcome in the less immersive configuration (i.e. desktop) and a similar learning outcome in both low-end and high-end VR systems. Even though low-end VR systems are less immersive and produce a lower level of virtual presence than high-end VR systems, the results support the use of low-end VR systems for educative applications.     

Efficient inter-domain traffic engineering with transit-edge hierarchical routing

The relentless growth of Internet, which has resulted in the increase of routing table sizes, requires consideration and new direction to address Internet scalability and resiliency. A possible direction is to move away from the flat legacy Internet routing to hierarchical routing, and introduce two-level hierarchical routing between edge networks and across transit networks. In this way, there is also an opportunity to separate the routing locator from the terminal identifier, to better manage IP mobility and mitigate important routing security issues. In this paper, we study the extended traffic engineering capabilities arising in a transit-edge hierarchical routing, focusing on those multi-homed edge networks (e.g., Cloud/content providers) that aim at increasing their Internet resiliency experience. We model the interaction between distant independent edge networks exchanging large traffic volumes using game theory, with the goal of seeking efficient edge-to-edge load-balancing solutions. The proposed traffic engineering framework relies on a non-cooperative potential game, built upon locator and path ranking costs, that indicates efficient equilibrium solution for the edge-to-edge load-balancing coordination problem. Simulations on real instances show that in comparison to the available standard protocols such as BGP and LISP, we can achieve a much higher degree of resiliency and stability.¹     

一类线性差分方程的动力学

本文给出了一类线性差分方程的充分条件,应用该条件解决了此线性差分方程解的收敛性、有界性等问题.     

基于云模型的多粒度彩色图像分割

图像信息中存在的不确定性问题会影响图像的分割效果.为此,提出一种基于粒计算和云模型的彩色图像分割算法.研究多粒度认知模型,在HSV颜色空间中利用云模型构建彩色图像的信息粒,进行多粒度、多层次的云粒合成,实现彩色图像分割.实验结果表明,与PCNN算法和K均值算法相比,该算法的分割效果较好.     

Lithiation and magnesiation of R5Sn3 (R = Y and Gd) alloys

The lithiation and magnesiation of binary R₅Sn₃ (R = Y and Gd) phases has been studied by XRD, SEM, EPMA and electrochemical methods. The formation of R₅Sn₃Li_x and R₅Sn₃Mg_x ternary hexagonal phases as the results of insertion of Li/Mg into octahedral voids were observed during the first stage of electrochemical lithiation and magnesiation respectively. During the second stage of the electrochemical lithiation and magnesiation is the decomposition of the hexagonal phase into new phases and substitution of tin atoms by Li/Mg are observed.     

Wearable fitness technology: A structural investigation into acceptance and perceived fitness outcomes

Wearable fitness technologies (WFT) track physical activity, such as steps taken, calories burned and workout intensity, through a device that is typically worn at all times. While the market for WFT devices continues to grow, current theoretical understanding of adoption is lacking. Thus, in an attempt to extend the Technology Acceptance Model (TAM), the current study employs a structural equation model to increase current understanding of wearable technology use. Further, to better understand the outcome of WFT use, the current study examines the relationship among health related outcomes of WFT use such as overall exercise behavior and perceptions of health. Results support the TAM and WFT use was significantly related to perceived health outcomes.     

基于混沌遗传算法的干道协调控制相位差优化

以城市交通干道的延误时间最小化为研究目标,通过对应用于交通干道协调控制相位差优化的遗传算法和混沌优化算法的研究分析,并结合两者的优点,提出一种基于Logistic映射的混沌遗传优化算法,进而得到各个路口的最佳相位差,并将新算法与已有算法进行对比仿真实验,实验结果证实了该方法在收敛性和优化效果上都得到了提高.