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Distributed localization using mobile beacons in wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2007年第4期14卷 7-12页

作者： KUANG xing-hong Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 China College of Engineering Science and Technology Shanghai FisheriesUniversity Shanghai 200090 China

A new distributed node localization algorithm named mobile beacons-improved particle filter （MB-IPF） was proposed. In the algorithm, the mobile nodes equipped with globe position system （GPS） move around in the wireless sensor network （WSN） field based on the Gauss-Markov mobility model, and periodically broadcast the beacon messages Each unknown node estimates its location in a fully distributed mode based on the received mobile beacons. The localization algorithm is based on the IPF and several refinements, including the proposed weighted centroid algorithm, the residual resampling algorithm, and the markov chain monte carlo （MCMC） method etc., which were also introduced for performance improvement. The simulation results show that our proposed algorithm is efficient for most applications.

关键词： Keywords wireless wensor network node localization,mobile beacons MB-IPF algorithm

Deviating from the nanorod shape： Shape-dependent plasmonic properties of silver nanorice and nanocarrot structures

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Frontiers of physics 2016年第2期11卷 45-55页

作者： hong-Yan Liang hong Wei hong-xing Xu Center for Nanoscience and Nanotechnology School of Physics and Technology and Institute for Advanced Studies Wuhan University Wuhan 430072 China Institute of Physics Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics Beijing 100190 China

Noble metallic nanostructures exhibit special optical properties resulting from excitation of surface plasmons. Among the various metallic nanostructures, nanorods have attracted particular attention because of their unique and intriguing shape-dependent plasmonic properties. Nanorods can sup- port transverse and longitudinal plasmon modes, the latter ones depending strongly on the aspect ratio of the nanorod. These modes can be routinely tuned from the visible to the near-infrared spectral regions. Although nanorods have been investigated extensively, there are few studies de- voted to nanostructures deviating from the nanorod shape. This review provides an overview of recent progress in the development of two kinds of novel quasi-one-dimensional silver nanostruc- tures, nanorice and nanocarrot, including their syntheses, crystalline characterizations, plasmonic property analyses, and performance in plasmonic sensing applications.

关键词： electron energy loss spectroscopy (EELS) localized surface plasmon resonance (LSPR),multipolar longitudinal plasmon mode nanocarrot nanorice plasmonic sensing

Recent Progress on COS-derived Polymers

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Chinese Journal of Polymer Science 2019年第10期37卷 951-958,I0002页

作者： Cheng-Jian Zhang xing-hong Zhang Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education) Department of Polymer Science & Engineering Zhejiang University

The synthesis of sulfur-containing polymer, a very promising functional material, has made a great progress in the past several years. This review is focused on the very recent advances in poly(monothiocarbonate)s derived from carbonyl sulfide(COS) and epoxides including biomass-derived epoxides. Of significance, metal-free catalyst systems, including triethyl borane/Lewis base pair and thiourea/Lewis base pair are developed for the alternating copolymerization of COS with epoxides. Thereof, the thiourea/Lewis base pair is highly active to the copolymerization of COS with epoxide in a living manner. Moreover, a series of crystalline poly(monothiocarbonate)s are presented, including the copolymers derived from COS with oxetane, ethylene oxide, enantiopure epichlorohydrin, and achiral mesoepoxides via enantioselective copolymerization. Based on these COS/epoxide copolymerization process, a variety of COS-based block copolymers with well-defined structure are presented.

关键词： Carbonyl sulfide Epoxide Copolymerization Poly(monothiocarbonate)

Maximum modulus principle estimates for one dimensional fractional diffusion equation

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 466-478页

作者： ZHU Lin RUI hong-xing School of Mathematics and Computer Science Ningxia University School of Mathematics Shandong University

We present scheme I for solving one-dimensional fractional diffusion equation with variable coefficients based on the maximum modulus principle and two Grunwald approxima- tions. Scheme II is obtained by using classic Crank-Nicolson approximations in order to improve the time convergence. Schemes are proved to be unconditionally stable and second-order accuracy in spatial grid size for the problem with order of fractional derivative belonging to [（√17- 1）/2, 2] using the maximum modulus principle. A numerical example is given to confirm the theoretical analysis result.

关键词： the maximum modulus principle the Griinwald approximation finite difference scheme frac-tional diffusion equation numerical analysis.

Organocatalytic polymerization

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Science China Chemistry 2019年第9期62卷 1087-1089页

作者： Cheng-Jian Zhang xing-hong Zhang Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education) Department of Polymer Science and EngineeringZhejiang University

Organocatalysis, defined as the use of small organic molecules for catalyzing chemical transformations, can be traced back more than a century and has become a thriving area over the past 20 years.

关键词： Organocatalytic polymerization organic molecules catalyzing chemical transformations

Dual cooperative organocatalysts for one-pot synthesis of polyester-polythiocarbonate block copolymers from multiple monomers

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Science China Chemistry 2020年第12期63卷 1807-1814页

作者： Cheng-Jian Zhang Xun Zhang xing-hong Zhang Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of EducationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

The sequential arrangement of multiple monomer units in a polymer chain remains a major challenge in synthetic *** we describe a versatile route to the novel polyester-polythiocarbonate block copolymer from commercially available lactones, epoxides, and carbonyl sulfide(COS). A bicomponent organocatalyst combining triazabicyclodecene(TBD) with triethyl borane(TEB) generates two types of tunable active sites, i.e., TBD-capped alcohol via hydrogen bond and TEB-capped alcohol via O→B coordination bond, which can successively catalyze ring-opening polymerization of lactones and ring-opening copolymerization of COS and epoxides from mixed monomers in one pot. Because of the reversible activated propagating anions and fast activity exchange between the active and dormant species, all of the polymer chains are enchained with both polyester and polythiocarbonate blocks. Kinetic determination quantitatively confirms the proposed mechanism. This method enables diverse lactones and epoxides to form sulfur-containing block copolymers with readily tunable structures.

关键词： block copolymer polyester polythiocarbonate organocatalysis polymer synthesis

Gravitational field around black hole induces photonic spin-orbit interaction that twists light

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Frontiers of physics 2017年第5期12卷 87-90页

作者： Deng Pan hong-xing Xu School of Physics and Technology Wuhan University Wuhan 430072 China

The spin-orbit interaction （SOI） of light has been intensively studied in nanophotonics because it enables sensitive control of photons＇ spin degree of freedom and thereby the trajectories of the photons, which is useful for applications such as signal encoding and routing. A recent study [Phys. Rev. Lett. 117, 166803 （2016）] showed that the SOI of photons manifests in the presence of a gradient in the permittivity of the medium through which the photons propagate; this enhances the scattering of circularly polarized light and results in the photons propagating along twisted trajectories. Here we theoretically predict that, because of the equivalence between an inhomogeneous dielectric medium and a gravitational field demonstrated in transformation optics, a significant SOI is induced onto circularly polarized light passing by the gravitational lens of a black hole. This leads to： i） the photons to propagate along chiral trajectories if the size of the black hole is smaller than the wavelength of the incident photons; ii） the resulting image of the gravitational lens to manifest an azimuthal rotation because of these chiral trajectories. The findings open for a way to probe for and discover subwavelength-size black holes using circularly polarized light.

关键词： spin-orbit interation black hole gravitational lens optical angular momentum

Effect of Mn Content on Microstructure and Cryogenic Mechanical Properties of a 7%Ni Steel

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Acta Metallurgica Sinica(English Letters) 2018年第7期31卷 699-705页

作者： hong-Wei Cao xing-hong Luo Guo-Feng Zhan Shi Liu School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China CAS Key Laboratory of Nuclear Materials and SafetyAssessment Institute of Metal ResearchChinese Academyof SciencesShenyang 110016China Research and Development Center of Wuhan Iron and Steel(Group)Corp Wuhan 430080China

The effect of Mn content on the microstructure and cryogenic mechanical properties of a 7% Ni steel was investigated within the Mn content range from 0.13% to 0.36%. The microstructure of the steel as determined by optical microscopy, scanning electron microscopy, transmission electron microscopy, electron backscattering diffraction and X-ray diffraction was presented, and the low-temperature mechanical properties were given. The size of prior austenite grain did not change a lot as Mn content increased. Film-like reversed austenite, having high stability, was found mainly in the specimens with lower Mn content; however, in the specimen with the highest Mn content, the role of Mn was not obvious in stabilizing reversed austenite. Besides, with increasing Mn content, the amount of reversed austenite at grain boundaries gradually decreased. The variable Mn content had a significant effect on cryogenic toughness~ but not apparent on cryogenic tensile strength or yield strength. An excellent combination of cryogenic tensile and impact properties was obtained when Mn content of steel was 0.13%.

关键词： 7% Ni steel Mn content Microstructure Reversed austenite Cryogenic mechanical properties

契合新质生产力要素的城乡规划学高质量教学体系建构策略研究

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黑龙江教育(高教研究与评估) 2025年第1期 4-7页

作者：强欢欢王兴鸿南京林业大学江苏南京210037 南京大学建筑规划设计研究院有限公司江苏南京210093

面对全球经济格局、社会环境及新技术的快速变革,高等教育正在寻求突破。城乡规划学作为关键学科,其教学体系的优化与重构,关乎城乡规划行业的创新与进步。在洞察新质生产力要素的基础上,系统探讨新质劳动者、新质劳动资料及新质劳动对... 详细信息

面对全球经济格局、社会环境及新技术的快速变革,高等教育正在寻求突破。城乡规划学作为关键学科,其教学体系的优化与重构,关乎城乡规划行业的创新与进步。在洞察新质生产力要素的基础上,系统探讨新质劳动者、新质劳动资料及新质劳动对象在城乡规划学教学体系中的关键作用与拓展方向,提出三大创新策略:一是建立以学生综合素质提升为基石,师资队伍优化为动力,管理效能提升为保障的多维度新质劳动者体系;二是整合多元化思想交流促创新,前沿技术深度融合强实践,高质量评价体系保成效的多层次新质劳动资料;三是实施宏观战略引领方向,中观学科交叉融合控制,微观教学实践落地的多角度新质劳动对象拓展,以期为城乡规划学教学体系改革和城乡规划产业的全要素生产率提升提供强有力的学术支撑。

关键词：新质生产力城乡规划学高质量发展教学体系建构