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An approach for machining distortion measurements and evaluation of thin-walled blades with small datum

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Chinese Journal of Aeronautics 2016年第6期29卷 1806-1814页

作者： Yu Jianhua chen Zhitong Jiang Zepeng School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China AVIC Commercial Aircraft Engine Manufacturing Co. Ltd.Shanghai 201306China Co-Innovation Center for Advanced Aero-Engine Beijing 100083China

Inspection techniques for aero-engine blades are a hot topic in industry. Since these blades have a sculptured surface and a small datum, measurement results may deviate from an actual position. There are few proper approaches compensating for non-uniform distribution errors that are within specified tolerance ranges. This study aimed to develop a meshing structure measuring approach for the distortion of blades via non-contact optical 3D scanning. A rough measurement and a registration procedure are initially adopted to rectify the coordinate system of a blade, which avoids the initial coordinate system errors caused by the small datum. A measurement path with meshing structure is then unfolded on the blade surface. For non-uniform distribution errors, the meshing structure measurement is more visual and clear than the traditional constant height curves method. All measuring points take only 7 min to complete, and the distribution of error is directly and accurately presented by the meshing structure. This study provides a basis for future research on distortion control and error compensation.

关键词： Free surface Machining distortion Optical testing Thin-walled workpiece Turbine blades

A NEW STATISTICAL APPROACH FOR THE ANALYSIS OF UNCERTAIN SYSTEMS

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Journal of Systems Science & Complexity 2009年第1期22卷 1-34页

作者： Xinjia chen Kemin ZHOU Jorge ARAVENA Department of Electrical Engineering Southern University Baton Rouge LA 70813 USA. Department of Electrical and Computer Engineering Louisiana State University Baton Rouge LA 70803 USA.

This paper addresses the issues of conservativeness and computational complexity of probabilistie robustness analysis. The authors solve both issues by defining a new sampling strategy and robustness measure. The new measure is shown to be much less conservative than the existing one. The new sampling strategy enables the definition of efficient hierarchical sample reuse algorithms that reduce significantly the computational complexity and make it independent of the dimension of the uncertainty space. Moreover, the authors show that there exists a one to one correspondence between the new and the existing robustness measures and provide a computationally simple algorithm to derive one from the other.

关键词： Computational complexity randomized algorithms risk analysis robustness analysis uncertain system.

Mechanical behavior of segment rebar of shield tunnel in construction stage

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 888-899页

作者： Jun-sheng chen Hai-hong MO Department of Civil Engineering South China University of Technology Guang＇zhou 510640 China State Key Laboratory of Subtropical Building Science South China University of Technology Guang＇zhou 510640 China

In this paper, a 3D finite element （FE） program ADINA was applied to analyzing a tunnel with 9 segment tings. The loads acting on these segment tings included the squeezing action of tail brush of shield machine under attitude deflection, the jacking forces, the grouting pressure and the soil pressure. The analyses focused on the rebar stress in two statuses：（1） normal construction status without shield machine squeezing; （2） squeezing action induced by shield machine under attitude deflection. The analyses indicated that the rebar stress was evidently affected by the construction loads. In different construction status, the rebar stress ranges from -80 MPa to 50 MPa, and the rebar is in elastic status. Even some cracks appear on segments, the stress of segment rebar is still at a low level. It is helpful to incorporate a certain quantity of steel fiber to improve the anti-crack and shock resistance performance.

关键词： Shield tunnel Construction Segment Rebar Finite element (FE) analysis

A modified multi-objective particle swarm optimization approach and its application to the design of a deepwater composite riser

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Acta Mechanica Sinica 2018年第2期34卷 275-284页

作者： Y.Zheng J.chen Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

A modified multi-objective particle swarm optimization method is proposed for obtaining Pareto-optimal solutions effectively. Different from traditional multiobjective particle swarm optimization methods, Kriging meta-models and the trapezoid index are introduced and integrated with the traditional one. Kriging meta-models are built to match expensive or black-box functions. By applying Kriging meta-models, function evaluation numbers are decreased and the boundary Pareto-optimal solutions are identified rapidly. For bi-objective optimization problems, the trapezoid index is calculated as the sum of the trapezoid’s area formed by the Pareto-optimal solutions and one objective axis. It can serve as a measure whether the Pareto-optimal solutions converge to the Pareto front. Illustrative examples indicate that to obtain Paretooptimal solutions, the method proposed needs fewer function evaluations than the traditional multi-objective particle swarm optimization method and the non-dominated sorting genetic algorithm II method, and both the accuracy and the computational efficiency are improved. The proposed method is also applied to the design of a deepwater composite riser example in which the structural performances are calculated by numerical analysis. The design aim was to enhance the tension strength and minimize the cost. Under the buckling constraint, the optimal trade-off of tensile strength and material volume is obtained. The results demonstrated that the proposed method can effec tively deal with multi-objective optimizations with black-box functions.

关键词： Multi-objective particle swarm optimization Kriging meta-model Trapezoid index Deepwater composite riser

Numerical study of soil-rock mixture:Generation of random aggregate structure

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Science China(Technological Sciences) 2018年第3期61卷 359-369页

作者： chen Li YANG YongTao ZHENG Hong State Key Laboratory of Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Key Laboratory of Urban Security and Disaster Engineering Ministry of Education Beijing University of Technology

The soil-rock mixture(SRM) is highly heterogeneous. Before carrying out numerical analysis,a structure model should be generated. A reliable way to obtain such structure is by generating random aggregate structure based on random sequential addition(RSA). The classical RSA is neither efficient nor robust since valid positions to place new inclusions are formulated by trial, which involves repetitive overlapping tests. In this paper, the algorithm of Entrance block between block A and B(EAB)is synergized with background mesh to redesign RSA so that permissible positions to place new inclusions can be predicted,resulting in dramatic improvement in efficiency and robustness.

关键词： soil-rock mixture(SRM) random aggregate structure(RAS) random sequential addition(RSA) EAB algorithm background mesh

Finite-Time Synchronization of Complex Networks With Intermittent Couplings and Neutral-Type Delays

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IEEE/CAA Journal of Automatica Sinica 2023年第10期10卷 2026-2028页

作者： Engang Tian Yi Zou Hongtian chen School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China

Dear Editor, This letter focuses on the finite-time synchronization(FTS) of neutral-type complex networks with intermittent couplings. Different from most of the existing references concerning neutral-type systems,a delay-independent dynamical event-triggering controller is considered, operating the same way as the intermittent coupling and excluding the Zeno behavior naturally.

关键词： neutral letter concerning

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Activation of pyroptosis by specific organelle-targeting photodynamic therapy to amplify immunogenic cell death for anti-tumor immunotherapy

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Bioactive Materials 2023年第7期25卷 580-593页

作者： Shuang Zeng chen chen Liuwei Zhang Xiaosheng Liu Ming Qian Hongyan Cui Jingyun Wang Qixian chen Xiaojun Peng School of Bioengineering Dalian University of Technology2 Linggong RoadHi-tech ZoneDalian116024China State Key Laboratory of Fine Chemicals Dalian University of Technology2 Linggong RoadHi-tech ZoneDalian116024China

Pyroptosis,a unique lytic programmed cell death,inspired tempting implications as potent anti-tumor strategy in pertinent to its potentials in stimulating anti-tumor immunity for eradication of primary tumors and ***,rare therapeutics have been reported to successfully stimulate *** view of the intimate participation of reactive oxygen species(ROS)in stimulating pyroptosis,we attempted to devise a spectrum of well-defined subcellular organelle(including mitochondria,lysosomes and endoplasmic reticulum)-targeting photosensitizers with the aim of precisely localizing ROS(produced from photosensitizers)at the subcellular compartments and explore their potentials in urging pyroptosis and immunogenic cell death(ICD).The subsequent investigations revealed varied degrees of pyroptosis upon photodynamic therapy(PDT)towards cancerous cells,as supported by not only observation of the distinctive morphological and mechanistic characteristics of pyroptosis,but for the first-time explicit validation from comprehensive RNA-Seq ***,in vivo anti-tumor PDT could exert eradication of the primary tumors,more importantly suppressed the distant tumor and metastatic tumor growth through an abscopal effect,approving the acquirement of specific anti-tumor immunity as a consequence of ***,pyroptosis was concluded unprecedently by our proposed organelles-targeting PDT strategy and explicitly delineated with molecular insights into its occurrence and the consequent ICD.

关键词： Pyroptosis Tumor Photodynamic therapy Immunogenic cell death Subcellular targeting

Host-Guest Chemistry and Nonlinear Optical Behaviors of Aluminum Molecular Rings

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Chinese Journal of Chemistry 2024年第21期42卷 2581-2588页

作者： Yi-Bo chen cheng-Yang Zhang Dan Luo Ran-Qi chen Jian Zhang Shu-Mei chen Wei-Hui Fang College of Chemistry Fuzhou UniversityFuzhouFujian350108 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian350002 China Fujian College University of Chinese Academy of SciencesNo.155 Yangqiao West RoadFuzhouFujian350002 China

Macrocyclic compounds are of great interest for their ability to capture guest molecules into their *** particular,host-guest interaction plays a crucial role in the formation of supramolecular ***,two host-guest supramolecular compounds,[Al_(8)(OH)_(8)(L)_(16)]·2HL(HL@AlOC-166,HL=4-Iodobenzoic acid)and[Al_(8)(OH)_(8)(L)_(8)(L1)_(8)]·2DMF(DMF@AlOC-166,HL1=isoamyl alcohol),are acquired by introducing different types of guest components based on the internal pore cavities of the aluminum molecular ring[Al_(8)(OH)_(8)(L)_(16)](AlOC-166).The inclusion of these guests is attributed to the presence of abundant hydrophilic OH serving as the hydrogen bond donors inward the ring ***-guest compounds usually exhibit superior nonlinear optical(NLO)response due to the existence of guest molecules that could change symmetry,dipole moments,charge distributions,***,the AlOC-166 achieved the best NLO results,although it had no guest molecules inside its molecular ring,which breaks the traditional *** reason for this trend can be explained by the difference in intermolecular force rather than intramolecular interaction,mainly related to the amount and strength ofπ···πand C—I···πinteractions in different *** work investigates the effect of host-guest interaction on NLO,representing a new perspective for designing optical limiting materials.

关键词： Host-guest chemistry Noncovalent interaction Nonlinear optical Aluminum molecular ring

Leafhopper salivary carboxylesterase suppresses JA-Ile synthesis to facilitate initial arbovirus transmission in rice phloem

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Plant Communications 2024年第9期5卷 116-135页

作者： Yunhua Chi Hongxiang Zhang Siyu chen Yu cheng Xiaofeng Zhang Dongsheng Jia Qian chen Hongyan chen Taiyun Wei Vector-borne Virus Research Center Fujian Province Key Laboratory of Plant VirologyInstitute of Plant VirologyFujian Agriculture and Forestry UniversityFuzhouFujian 350002China

Plant jasmonoyl-L-isoleucine(JA-Ile)is a major defense signal against insect feeding,but whether or how insect salivary effectors suppress JA-Ile synthesis and thus facilitate viral transmission in the plant phloem remains *** carboxylesterases(CarEs)are the third major family of detoxification ***,we identify a new leafhopper CarE,CarE10,that is specifically expressed in salivary glands and is secreted into the rice phloem as a saliva *** CarE10 directly binds to rice jasmonate resistant 1(JAR1)and promotes its degradation by the proteasome ***,the direct association of CarE10 with JAR1 clearly impairs JAR1 enzyme activity for conversion of JA to JA-Ile in an in vitro JAIle synthesis system.A devastating rice reovirus activates and promotes the co-secretion of virions and CarE10 via virus-induced vesicles into the saliva-storing salivary cavities of the leafhopper vector and ultimately into the rice phloem to establish initial ***,a virus-mediated increase in CarE10 secretion or overexpression of CarE10 in transgenic rice plants causes reduced levels of JAR1 and thus suppresses JA-Ile synthesis,promoting host attractiveness to insect vectors and facilitating initial viral *** findings provide insight into how the insect salivary protein CarE10 suppresses host JA-Ile synthesis to promote initial virus transmission in the rice phloem.

关键词： leafhopper salivary protein CarE10 JAR1 degradation JA-Ile synthesis rice phloem initial viral transmission