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871.
Numerous privacy-preserving issues have emerged along with the fast development of the Internet of Things. In addressing privacy protection problems in Wireless Sensor Networks(WSN), secure multi-party computation is considered vital, where obtaining the Euclidian distance between two nodes with no disclosure of either side’s secrets has become the focus of location-privacy-related applications. This paper proposes a novel Privacy-Preserving Scalar Product Protocol(PPSPP) for wireless sensor networks. Based on PPSPP, we then propose a Homomorphic-Encryption-based Euclidean Distance Protocol(HEEDP) without third parties. This protocol can achieve secure distance computation between two sensor nodes. Correctness proofs of PPSPP and HEEDP are provided, followed by security validation and analysis. Performance evaluations via comparisons among similar protocols demonstrate that HEEDP is superior; it is most efficient in terms of both communication and computation on a wide range of data types, especially in wireless sensor networks. 相似文献
872.
HAN Tao LU XiaoChun WANG Xue RAO YongNan ZOU DeCai YANG JianFei & WU YangYang National Time Service Center Xi'an China Key Laboratory of Precision Navigation Timing Technology Chinese Academy of Sciences Graduate University of the Chinese Academy of Sciences Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the interoperability with the existing ones necessitates the study of the assessment algorithm of this idea.In this paper,an assessment algorithm for interoperability comprehensive benefits based on the differential equation dynamical system is discussed.There are two important aspects in GNSS tha... 相似文献
873.
FAN QiuBo College of Mathematics Physics Xuzhou Institute of Technology Xuzhou China 《中国科学:物理学 力学 天文学(英文版)》2011,(3)
We demonstrate that an arbitrary Bell state can be achieved in a two qubit anisotropic Heisenberg XY chain via Lyapunov control. During the whole process, we only need to apply an external field along a given direction to a single qubit. This control strategy is effective for all initial states in the four-dimensional Hilbert space where the target state is asymptotically stable. The effects of imperfections on the fidelity for the target state such as Gaussian leakage of local control and localized dephasi... 相似文献
874.
WANG QianXin & XU TianHe School of Information Physics Geomatics Engineering Central South University Changsha China Geodesy Department Xi'an Research Institute of Surveying Mapping Xi'an 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
The truncation error and propagation error are analyzed for velocity determination through differential GPS carrier phase observations,and an approach for the choice of the best number of points for the central difference method is developed.In order to overcome the disadvantages of existing GPS velocity determination methods,a new velocity determination algorithm is presented,based on combining carrier phase and Doppler observations.The basic idea is that two types of observation are combined by adding the... 相似文献
875.
将Mg粉、Zr粉和B粉按比例混合获得Mg1-xZrxB2(x=5%10%和20%),压制成型后,在流通氩气的条件下于800℃烧结2h.利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)分析烧结后样品的显微结构和化学组成,采用差热分析(DTA)观察Zr掺杂对MgB2分解温度的影响,并用物性测试仪(PPMS)测试样品的超... 相似文献
876.
XU ShangJin WU ZhengFei & DENG YunPing College of Mathematics Information Science Guangxi University Nanning 《中国科学A辑(英文版)》2009,(2)
A graph is said to be s-arc-regular if its full automorphism group acts regularly on the set of its s-arcs. In this paper, we investigate connected cubic s-arc-regular Cayley graphs of finite nonabelian simple groups. Two suffcient and necessary conditions for such graphs to be 1- or 2-arc-regular are given and based on the conditions, several infinite families of 1-or 2-arc-regular cubic Cayley graphs of alternating groups are constructed. 相似文献
877.
We study the medium modified fragmentation function in high-energy heavy-ion collisions. We show that the ACSX and QW formalisms are equivalent to each other in the high-Q2 limit in both theoretical and numerical aspects. 相似文献
878.
QI GuoPeng JIANG Feng SUN XueWen & ZHAO SuoQi School of Chemical Engineering Tianjin University Tianjin China State key Laboratory of Heavy Oil Processing Petroleum University of China Beijing China 《中国科学:化学》2010,(5)
The isotope exchange method was employed to investigate the catalytic mechanism of ionic liquid in alkylation of benzenes with olefins.It is proposed that alkylation was induced by the Lewis acid AlCl3 which attracted π electrons of 1-dodecene to shift toward 1-carbon,thus forming a carbonium ion.The carbonium ion further reacted with benzenes to form a complex.Due to unstabilit of the complex,a deuterated ring proton was transferred into an electronegative 1-carbon of the side chain to substitute for the A... 相似文献
879.
Editorial Office of Acta Physico-Chimica Sinica 《物理化学学报》2020,36(9):2003059-0
正功能纳米材料是化学、物理、生物和材料科学多学科交叉的前沿,是纳米科技发展的基础。功能纳米材料集中体现了小尺寸、精准控制、高集成度和强相互作用等现代科学技术发展的特点,是将量子力学效应工程化或技术化的最好载体之一,呈现独特的光、电、磁、机械和催化等性质,在物理、生物、化学和材料学领域中都有广泛的研究和应用前景。 相似文献
880.
通过测量不同工艺条件下玻璃绝缘子中的气孔率和最大气泡直径,以及观察底盘表面的玻璃飞溅情况,研究了熔封气氛、熔封温度、熔封时间、氧化膜类型和厚度对玻璃绝缘子中气孔率和玻璃飞溅的影响.结果表明,玻璃绝缘子中气孔率与可伐合金底盘表面的飞溅程度有一定的关系.可伐合金表面Fe3O4氧化物与玻璃中SiO2发生化学反应是玻璃绝缘子中气泡的一个重要来源,也是引起玻璃飞溅的因素.熔封气氛和氧化膜厚度对气孔率和玻璃飞溅影响最大.推荐的工艺条件是在可伐合金表面生成厚度约1μm的FeO氧化膜,然后与玻坯在950~980℃工厂条件的气氛中熔封30~40 min. 相似文献