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Integration of uniform design and quantum-behaved particle swarm optimization to the robust design for a railway vehicle suspension system under different wheel conicities and wheel rolling radii

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Acta Mechanica Sinica 2017年第5期33卷 963-980页

作者： Yung-chang cheng cheng-Kang Lee Department of Mechanical and Automation Engineering Kaohsiung First University of Science and Technology Department of Industrial Engineering and Management Cheng Shiu University

This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspension system. Based on the new nonlinear creep model derived from combining Hertz contact theory, Kalker's linear theory and a heuristic nonlinear creep model, the modeling and dynamic analysis of a 24 degree-of-freedom railway vehicle system were investigated. The Lyapunov indirect method was used to examine the effects of suspension parameters, wheel conicities and wheel rolling radii on critical hunting speeds. Generally, the critical hunting speeds of a vehicle system resulting from worn wheels with different wheel rolling radii are lower than those of a vehicle system having original wheels without different wheel rolling radii. Because of worn wheels, the critical hunting speed of a running railway vehicle substantially declines over the long term. For safety reasons, it is necessary to design the suspension system parameters to increase the robustness of the system and decrease the sensitive of wheel noises. By applying UD and QPSO, the nominal-the-best signal-to-noise ratio of the system was increased from -48.17 to -34.05 dB. The rate of improvement was 29.31%. This study has demonstrated that the integration of UD and QPSO can successfully reveal the optimal solution of suspension parameters for solving the robust design problem of a railway vehicle suspension system.

关键词： Speed-dependent nonlinear creep model Quantum-behaved particle swarm optimization Uniform design Wheel rolling radius Hunting stability

Structural biology revolution led by technical breakthroughs in cryo-electron microscopy

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Chinese Physics B 2018年第5期27卷 49-58页

作者： chang-cheng Yin Department of Biophysics College of Basic Medicine Peking University Health Science Center Peking University Beijing 100191 China

Recent technical breakthroughs in cryo-electron microscopy（cryo-EM） revolutionized structural biology, which led to the 2017 Nobel Prize in chemistry being awarded to three scientists, Jacques Dubochet, Joachim Frank, and Richard Henderson, who made groundbreaking contributions to the development of cryo-EM. In this review, I will give a comprehensive review of the developmental history of cryo-EM, the technical aspects of the breakthrough in cryo-EM leading to the structural biology revolution, including electron microscopy, image recording devices and image processing algorithms,and the major scientific achievements by Chinese researchers employing cryo-EM, covering protein complexes involved in or related to gene expression and regulation, protein synthesis and degradation, membrane proteins, immunity, and ***, I will give a perspective outlook on the development of cryo-EM in the future.

关键词： cryo-electron microscopy (cryo-EM) structural biology protein molecular machinery

Transcriptome analysis in the beet webworm, Spoladea recurvalis （Lepidoptera： Crambidae）

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Insect Science 2018年第1期25卷 33-44页

作者： Jian-cheng chang Srinivasan Ramasamy A VRDC - The World Vegetable Center Shanhua Tainan Taiwan China

The beet webworm, Spoladea recurvalis Fabricius, is a destructive pest on vegetable crops in tropics and subtropics; its main host plant is amaranth. It has become imperative to develop non-chemical methods to control S. recurvalis on amaranth. However, the lack of molecular information about this species has hindered the development of novel pest management strategies. In this study, high-throughput RNA sequencing covering de novo sequence assemblies, functional annotation of transcripts, gene function classification and enrichment was performed on S. recurvalis. Illumina sequencing generated a total of 120 435 transcript contigs ranging from 201 to 22 729 bases with a mean length of 688 bases. The assembled transcripts were subjected to Basic Local Alignment Search Tool- X （BLASTX） to obtain the annotations against non-redundant, Swiss-Prot, Clusters of Orthologous Groups （COG） and Kyoto Encyclopedia of Genes and Genomes （KEGG） protein databases. A subset of 58 225 transcript sequences returned hits from known proteins in the National Center for Biotechnology Information database, and the majority of the transcript sequences had the highest number of hits for Danausplexippus （50.43%）. A total of 1217 Gene Ontology-level 3 annotations were assigned to 51 805 transcripts, while 39 650 transcripts were predicted as functional protein-coding genes in the COG database and 20 037 transcripts were enriched to KEGG pathways. We identified 40 putative genes related to pheromone production and reception in S. recurvalis, with the expression of one gene between 0.29 and 1141.79 fragments per kilo base per million （FPKM） reads. The transcriptome sequence of S. recurvalis is a first step toward offering a comprehensive genomic resource which would enable better understanding of molecular mechanisms to enable development of effective pest management practices for this species.

关键词： pheromone protein-coding genes putative genes Spoladea recurvalis transcriptome

Anatomizing the Ocean's Role in Maintaining the Pacific Decadal Variability

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Advances in Atmospheric Sciences 2014年第3期31卷 611-623页

作者： Jia-Yuh YU cheng-Wei chang Department of Atmospheric Sciences Chinese Culture University Graduate Institute of Earth Science Chinese Culture University

ABSTRACT The role of ocean dynamics in maintaining the Pacific Decadal Variability （PDV） was investigated based on simulation results from the Parallel Ocean Program （POP） ocean general circulation model developed at the Los Alamos National Laboratory （LANL）. A long-term control simulation of the LANL-POP model forced by a reconstructed coupled wind stress field over the period 1949-2001 showed that the ocean model not only simulates a reasonable climatology, but also produces a climate variability pattem very similar to observed PDV. In the Equatorial Pacific （EP） region, the decadal warming is confined in the thin surface layer. Beneath the surface, a strong compensating cooling, accompanied by a basin-wide-scale overturning circulation in opposition to the mean flow, occurs in the thermocline layer. In the North Pacific （NP） region, the decadal variability nonetheless exhibits a relatively monotonous pattern, characterized by the dominance of anomalous cooling and eastward flows. A term balance analysis of the perturbation heat budget equation was conducted to highlight the ocean＇s role in main- taining the PDV-like variability over the EP and NP regions. The analyses showed that strong oceanic adjustment must occur in the equatorial thermocline in association with the anomalous overturning circulation in order to maintain the PDV-like variability, including a flattening of the equatorial thermocline slpoe and an enhancement of the upper ocean＇s stratification （stability）, as the climate shifts from a colder regime toward a warmer one. On the other hand, the oceanic response in the extratropical region seems to be confined to the surface layer, without much participation from the subsurface oceanic dynamics.

关键词： Pacific decadal variability term balance analysis perturbation heat budget equation

Effect of sintering parameters on the microstructure and thermal conductivity of diamond/Cu composites prepared by high pressure and high temperature infiltration

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 180-186页

作者： Hui Chen cheng-chang Jia Shang-jie Li School of Materials Science and Engineering University of Science and Technology Beijing Shenzhen Haimingrun Industrial Co. Ltd.

Pure Cu composites reinforced with diamond particles were fabricated by a high pressure and high temperature （HPHT） infiltration technique. Their microstructural evolution and thermal conductivity were presented as a function of sintering parameters （temperature, pressure, and time）. The improvement in interfacial bonding strength and the maximum thermM conductivity of 750 W/（m.K） were achieved at the optimal sintering parameters of 1200℃, 6 GPa and 10 min. It is found that the thermal conductivity of the composites depends strongly on sintering pressure. When the sintering pressure is above 6 GPa, the diamond skeleton is detected, which greatly contributes to the excellent thermal conductivity.

关键词： metallic matrix composites particle reinforced composites copper diamonds infiltration microstructuralevolution thermal conductivity

Lithiation-enhanced charge transfer and sliding strength at the silicon-graphene interface:A first-principles study

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Acta Mechanica Solida Sinica 2017年第3期30卷 254-262页

作者： cheng chang Xiaoyan Li Zhiping Xu Huajian Gao Applied Mechanics Laboratory Department of Engineering Mechanics Center for Nano and Micro MechanicsCenter for Advanced Mechanics and Materials Tsinghua University School of Engineering Brown University

The application of silicon as ultrahigh capacity electrodes in lithiumion batteries has been limited by a number of mechanical degradation mechanisms including fracture, delamination and plastic ratcheting, as a result of its large volumetric change during lithiation and delithiation. Graphene coating is one feasible technique to mitigate the mechanical degradation of Si anode and improve its conductivity. In this paper, first-principles calculations are performed to study the atomic structure, charge transfer and sliding strength of the interface between lithiated silicon and graphene. Our results show that Li atoms segre- gate at the （lithiated） Si-graphene interface preferentially, donating electrons to graphene and enhancing the interfacial sliding resistance. Moreover, the interfacial cohesion and sliding strength can be further enhanced by introducing single-vacancy defects into graphene. These findings provide insights that can guide the design of stable and efficient anodes of silicon/graphene hybrids for energy storage applications.

关键词： Lithium-ion batteries Silicon anode Graphene coating Interracial sliding strength First-principles calculations

Synchro-control of Twin-rudder with Cloud Model

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International Journal of Automation and computing 2012年第1期9卷 98-104页

作者： Sheng Liu Xu-cheng chang College of Automation Harbin Engineering UniversityHarbin 150001PRC

In ships having two rudders, an angle error exists if there is a difference in structural and electrical parameters in two steering gear systems. Such an error also results in reduced efficiency of ship maneuverability during navigation. For the sake of reducing the angle error, a synchro-ballistic control approach based on cloud model is proposed in this paper. First, the mechanism model of steering gear system is introduced. Second, the structure of synchro-control system of twin-rudder is proposed based on the master-slave control strategy. Third, synchro-ballistic controller based on cloud model is designed to solve the nonlinearity and uncertainty of system. Finally, the designed controller is tested via simulation under two different situations. The simulated results demonstrate that this method is simple and has stronger robustness against the variation of states and parameters of plants. Hence, the validity and reliability of the method is proved for synchro-control of two rudders, which is a significant engineering application.

关键词： Ship steering steering gear twin-rudder synchro-ballistic cloud model.

On the CR Poincaré–Lelong Equation, Yamabe Steady Solitons and Structures of Complete Noncompact Sasakian Manifolds

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Acta Mathematica Sinica,English Series 2018年第8期34卷 1313-1344页

作者： Der Chen chang Shu cheng chang Ying Bo HAN Chien LIN Department of Mathematics and Statistics Georgetown University Washington D. C. 20057 USA Graduate Institute of Applied Science and Engineering Fu Jen Catholic University Taipei 242 Taiwan China Yau Mathematical Sciences Center Tsinghua University Beijing 100084 P. R. China School of Mathematics and Statistics Xinyang Normal University Xinyang 464000 P. R. China Department of Mathematics National Tsing Hua University Hsinchu 30013 Taiwan China

In this paper, we solve the so-called CR Poincare-Lelong equation by solving the CR Poisson equation on a complete noncompact CR （2n ＋ 1）-manifold with nonegative pseudohermitian bisectional curvature tensors and vanishing torsion which is an odd dimensional counterpart of Kahler geometry. With applications of this solution plus the CR Liouvelle property, we study the structures of complete noncompact Sasakian manifolds and CR Yamabe steady solitons.

关键词： CR Poisson equation CR Poincare-Lelong equation CR Yamabe solitons

Guest Editorial:Intelligent Video Surveillance and Related Technologies

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Journal of Electronic Science and Technology 2017年第2期15卷 113-114页

作者： Chung-Lin Huang cheng-chang Lien I-cheng chang Chih-Yang Lin Asia University "Chung-Hua University" Dong Hwa University Yuan-Ze University

Due to the increasing demand for developing a secure and smart living environment, the intelligent video surveillance technology has attracted considerable attention. Building an automatic, reliable, secure, and intelligent video surveillance system has spawned large research projects and triggered many popular research topics in several international conferences and workshops recently. This special issue of Journal of ElecWonic Science and Technology （JEST） aims to present recent advances in video surveillance systems which address the observation of people in an environment, leading to a real-time description of their actions and interactions.

关键词： is for been Guest Editorial Intelligent Video Surveillance and Related Technologies of in body that