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Robust location algorithm for NLOS environments

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Journal of Systems Engineering and Electronics 2008年第4期19卷 812-818页

作者： huang Jiyan Wan qun Dept of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

One of the main problems facing accurate location in wireless communication systems is non-line-of- sight （NLOS） propagation. Traditional location algorithms are based on classical techniques under minimizing a least-squares objective function and it loses optimality when the NLOS error distribution deviates from Gaussian distribution. An effective location algorithm based on a robust objective function is proposed to mitigate NLOS errors. The proposed method does not require the prior knowledge of the NLOS error distribution and can give a closed-form solution. A comparison is performed in different NLOS environments between the proposed algorithm and two additional ones （LS method and Chan＇s method with an NLOS correction）. The proposed algorithm clearly outperforms the other two.

关键词： wireless location time-of-arrival non-line-of-sight robust objective function

Variable stiffness design of redundantly actuated planar rotational parallel mechanisms

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Chinese Journal of Aeronautics 2017年第2期30卷 818-826页

作者： Li Kangkang Jiang Hongzhou Cui Zuo huang qun School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

Redundantly actuated planar rotational parallel mechanisms（RAPRPMs） adapt to the requirements of robots under different working conditions by changing the antagonistic internal force to tune their *** geometrical parameters of the mechanism impact the performances of modulating *** expressions relating stiffness and geometrical parameters of the mechanism were formulated to obtain the necessary conditions of variable stiffness.A novel method of variable stiffness design was presented to optimize the geometrical parameters of the *** stiffness variation with the internal force was *** dynamic change of stiffness with the dynamic location of the mechanism was minimized,and the robustness of stiffness during the motion of the mechanism was *** new approach to variable stiffness design can enable off-line planning of the internal force to avoid the difficulties of on-line control of the internal force.

关键词： Internal force Parallel mechanisms Redundantly actuated Robustness Variable stiffness

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某应急酒店刚性连体结构抗震设计要点及分析

山西建筑 2025年第4期51卷 47-53页

作者：揭智渊董永贤黄群杨小勇杭州千城建筑设计集团股份有限公司浙江杭州310000 五洲工程顾问集团有限公司浙江杭州310000 汉嘉设计集团股份有限公司浙江杭州310000

浙江某应急酒店项目由A,B两座塔楼通过顶部大跨连廊连接,连廊采用钢桁架结构形式,净跨约34.5 m,该项目结构因多项“不规则”而为超限结构。为达成预定的抗震性能目标,对结构的各“不规则”项采取了有针对性的设计加强策略。采用YJK和PM... 详细信息

浙江某应急酒店项目由A,B两座塔楼通过顶部大跨连廊连接,连廊采用钢桁架结构形式,净跨约34.5 m,该项目结构因多项“不规则”而为超限结构。为达成预定的抗震性能目标,对结构的各“不规则”项采取了有针对性的设计加强策略。采用YJK和PMSAP两种计算分析软件,对连体结构进行对比,通过性能化设计和动力弹塑性时程分析,探究结构在设防地震及罕遇地震条件下的响应特性。再针对连廊部分,进行舒适度及温度应力等专项分析。基于计算与分析结果,针对结构核心关键部位以及结构薄弱部位实施有效加强策略,达到既定的抗震性能化设计目标,确保了结构的安全与可靠。

关键词：超限连体结构刚性连接抗震性能化设计弹塑性时程分析钢连廊专项分析

Transport of velocity alignment particles in random obstacles

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Chinese Physics B 2018年第8期27卷 164-169页

作者： Wei-jing Zhu Xiao-qun huang Bao-quan Ail Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal University Basic Teaching Department Neusoft Institute Guangdong

We numerically investigate the trapping behaviors of aligning particles in two-dimensional （2D） random obstacles system. Under the circumstances of the effective diffusion rate and the average velocity tend to zero, particles are in trapped state. In this paper, we examine how the system parameters affect the trapping behaviors. At the large self-propelled speed, the ability of nematic particles escape from trapping state is enhancing rapidly, in the meanwhile the polar and free particles are still in trapped state. For the small rotation diffusion coefficient, the polar particles circle around （like vortices） the obstacles and here particles are in trapped state. Interestingly, only the partial nematic particles are trapped in the confined direction and additional particles remain flowing. In the free case, the disorder particle-particle collisions impede the motion in each other＇s directions, leading the free particles to be trapped. At the large rotation diffusion coefficient, the ordered motion of aligning particles disappear, particles fill the sample evenly and are self-trapped around obstacles. As the particles approach the trapping density due to the crowding effect the particles become so dense that they impede each other＇s motion. With the increasing number of obstacles, the trajectories of particles are blocked by obstacles, which obstruct the movement of particles. It is worth noting that when the number of the obstacles are large enough, once the particles are trapped, the system is permanently absorbed into a trapped state.

关键词： Brownian motion self-propelled particles stochastic processes

Heat Treatment of Cold-Rolled Low-Carbon Si-Mn Dual Phase Steels

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Journal of Iron and Steel Research International 2010年第1期17卷 54-58页

作者： LUO Juan-juan SHI Wen huang qun-fei LI Lin Material Science and Engineering College Shanghai University Shanghai 200072 China

The effects of overageing （OA） and vanadium addition on microstructure and properties of cold-rolled lowcarbon Si-Mn dual phase （DP） steel sheets are studied. The results show that the microstructure and mechanical properties of DP steels are greatly affected by OA temperature. When OA is done at low temperatures （473 -- 573 K）, the elongation rate increases sharply while both the yield strength and tensile strength decrease significantly, When OA is done at high temperatures （〉573 K）, the elongation does not further increase, but the yield strength increases and tensile strength decreases, which deteriorates the mechanical properties of the steel. The results also show that both the strength and the tempering stability can be significantly improved by vanadium microalloying. Finally, the optimum OA temperature for the traditional steel appears to be around 523 K, while it is around 573 K for the V-containing steel, resulting in the best overall mechanical properties.

关键词： dual phase steel overageing microstructure mechanical property vanadium

Syntheses, Structures and Photoluminescence of Two New Europium（III） Coordination Polymers

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Chinese Journal of Structural Chemistry 2012年第8期31卷 1067-1074页

作者： LI Min huang qun-Zeng FENG Yu-Quan SHI Heng-Zhen Department of Chemistry Henan Institute of EducationZhengzhou 450046China College of Chemistry and Pharmacy Engineering Nanyang Normal UniversityNanyang 473061China

Two new europium （Ⅲ） coordination polymers formulated as Eu2（H20）a（ox）4]· （CsH6N）2-2H20 （1） and Eu2（ad）3（H20）4]＇0.25H20 （2）（H20x = oxalic acid, H2ad = adipic acid） have been synthesized from the self-assembly of lanthanide ions Eu^3＋ with flexible oxalic and adipic acid ligands, respectively. Structural analyses revealed that complex 1 exhibits three-dimensional metalorganic frameworks, and 2 has intricate two-dimensional interpenetrated metal-organic networks. In addition, the photoluminescent properties of complexes 1 and 2 were discussed in detail, which shows strong red emission, corresponding to ^5Do →^7F？ transition of Eu^3＋ ions.

关键词： coordination polymer lanthanide photoluminescence

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The role of flavonoids in mitigating food originated heterocyclic aromatic amines that concerns human wellness

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Food Science and Human Wellness 2023年第4期12卷 975-985页

作者： Hui Teng Hongting Deng Chang Zhang Hui Cao qun huang Lei Chen College of Food Science and Technology Guangdong Ocean UniversityGuangdong Provincial Key Laboratory of Aquatic Product Processing and SafetyGuangdong Province Engineering Laboratory for Marine Biological ProductsGuangdong Provincial Engineering Technology Research Center of SeafoodKey Laboratory of Advanced Processing of Aquatic Product of Guangdong Higher Education InstitutionZhanjiang 524088China Faculty of Food Science and Technology University of VigoVigo 36310Spain Meat Processing Key Laboratory of Sichuan Province School of Food and Biological EngineeringChengdu UniversityChengdu 610106China

Meat products are an important part in our daily diet,providing valuable nutrients for the human ***,heating processes cause the meat to become more appetizing with changes in texture,appearance,flavor,and chemical properties by the altering of protein structure and other *** one kind of cooking-induced contaminants,heterocyclic aromatic amines(HAAs)are widely present in protein aceous food products with strong carcinogenic and mutagenic *** order to promote the safety of traditional meat products,this review focused on the formation,metabolism,biological monitoring and inhibitory mechanism of *** overview of the formation pathways,hazards,and control methods of HAAs during food processing in recent years was studied,aiming to provide some valuable information for exploring effective methods to inhibit the production of associated hazards during food *** selection of different types of flavonoids to explore their effects on the formation of HAAs in an actual barbecue system can provide theoretical reference for effectively controlling the formation of HAAs and reducing their harm to human health.

关键词： Heterocyclic aromatic amines Flavonoids Hazardous control Precursors

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Biological Effects of Low Energy N^+ Beams Implantation on Calluses of Autotetraploid Rice

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Journal of Integrative Agriculture 2013年第11期12卷 2045-2055页

作者： ZHAO Shuai-peng huang qun-ce LIANG Qiu-xia ZHANG Shu-gen JIAO Zhen huang Wei-zhou Province Key Laboratory of Ion Beam Bioengineering College of Physics and EngineeringZhengzhou University Qingdao Yuance Biological Technology Co.Ltd.

Calluses of two autotetraploid rice （DPR （4） and Zijing （4）） were implanted with 30 KeV N＋beams at doses ranging from 1.0×1015 to 9.0×1015 ions cm-2. The differentiation rates of calluses, the concentration of malondialdehyde （MDA）, the activities of superoxide dismutase （SOD）, catalase （CAT） and peroxidase （POD）, and the change of esterase （EST） spectrum were measured and analyzed on the calluses stage. The results showed that differentiation rates of calluses under 3.0×1015 ions cm-2 （（46.12±2.01）%） were higher than the other treatment groups in DPR （4）, and those of Zijing （4） were similar under the doses of 1.0×1015, 3.0×1015 and 5.0×1015 ions cm-2 （（40.55±2.74）, （37.77±3.04） and （34.56±2.65）%） and were higher than that of 7.0×1015 and 9.0×1015 ions cm-2. When the doses were 3.0×1015 and 5.0×1015 ions cm-2, the activities of SOD, POD and CAT were notably enhanced, and the accumulation of MDA content was markedly alleviated in the implanted calluses of two materials, as well as the activity of EST was increased by the additional isforms DPR （4）. Whereas the anti-oxidative systems and enzymes spectrum of EST were destroyed seriously, the accumulation of MDA was signiifcantly aggravated, also the differentiation rate of calluses reduced sharply and almost closed to zero when the implantation doses were 7.0×1015 and 9.0×1015 ions cm-2. It suggested that the proper dose of ion implantation effectively maintained the normal membrane structure and metabolism, and it would be also a feasible approach for autotetraploid rice to improve its genetic characteristics at calluses stage. Additionally, the differences of the radiation resistance between DPR （4） and Zijing （4） could be related to the different genotypes.

关键词： ion beams peroxidase (POD) superoxide dismutase (SOD) catalase (CAT) esterase (EST) malondialdehyde(MDA) autotetraploid rice

Introduction to the Special Issue on Modeling of Heterogeneous Materials

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 1-3页

作者： Lisheng Liu Xihua Chu Xinhua Yang Jianzhong Chen qun huang Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics Wuhan University of TechnologyWuhan430070China School of Civil Engineering Wuhan UniversityWuhan430070China School of Civil Engineering and Mechanics Huazhong University of Science and TechnologyWuhan430070China

In order to make up for the shortcomings of homogeneous materials and meet the needs of industry development,heterogeneous materials have been increasingly applied in aviation,automobile,bridge and other *** materials refer to advanced materials with non-uniform *** adjusting the structure or composition of heterogeneous materials,their performance may change in a specific direction to adapt to different environments and achieve special *** achieve wide applications of homogeneous materials,it is very important to be able to predict the performance and material response of heterogeneous *** method is a basic and important method to accomplish this *** methods for studying heterogeneous materials include finite element method(FEM),molecular dynamics(MD),peridynamics(PD)and so on.

关键词： materials. method shortcomings