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General Decay for a Thermoelastic Problem of a Microbeam with Gurtin-Pipkin Thermal Law

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 426-440页

作者： dong-qin chen Wen-jun LIU zhi-jing chen School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

In this paper,we study the well-posedness and the asymptotic stability of a one-dimensional thermoelastic microbeam system,where the heat conduction is given by Gurtin-Pipkin thermal *** first establish the well-posedness of the system by using the semigroup arguments and Lumer-Phillips *** then obtain an explicit and general formula for the energy decay rates through perturbed energy method and some properties of the convex functions.

关键词： microbeam system Gurtin-Pipkin thermal law well-posedness general decay

Structural Safety Assessment for FLNG-LNGC System During Offloading Operation Scenario

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China Ocean Engineering 2017年第2期31卷 192-201页

作者： HU zhi-qiang ZHANG dong-wei ZHAO dong-ya chen Gang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China Marine Design & Research Institute of China Shanghai 200240 China Nantong COSCO KHI Ship Engineering Co. Ltd Nantung 226005 China

The crashworthiness of the cargo containment systems （CCSs） of a floating liquid natural gas （FLNG） and the side structures in side-by-side offioading operations scenario are studied in this paper. An FLNG vessel is exposed to potential threats from collisions with a liquid natural gas carrier （LNGC） during the offioading operations, which has been confirmed by a model test of FLNG-LNGC side-by-side offioading operations. A nonlinear finite element code LS-DYNA is used to simulate the collision scenarios during the offioading operations. Finite element models of an FLNG vessel and an LNGC are established for the purpose of this study, including a detailed LNG cargo containment system in the FLNG side model. Based on the parameters obtained from the model test and potential dangerous accidents, typical collision scenarios are defined to conduct a comprehensive study. To evaluate the safety of the FLNG vessel, a limit state is proposed based on the structural responses of the LNG CCS. The different characteristics of the structural responses for the primary structural components, energy dissipation and collision forces are obtained for various scenarios. Deformation of the inner hull is found to have a great effect on the responses of the LNG CCS, with approximately 160 mm deformation corresponding to the limit state. Densely arranged web frames can absorb over 35% of the collision energy and be proved to greatly enhance the crashwo- rthiness of the FLNG side structures.

关键词： collision FLNG LNGC numerical simulation model test side-by-side offioading cargo containment system

Science Letters:A synthetic Toll-like receptor 2 ligand decreases allergic immune responses in a mouse rhinitis model sensitized to mite allergen

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 279-285页

作者： cheng ZHOU Xiao-dong KANG zhi chen Institute of Infectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Experimental Animal Center School of Medicine Hangzhou Teacher＇s College Hangzhou 310018 China

It has been proposed that activation of Toll-like receptors （TLRs） plays crucial roles in the polarization of adaptive immune responses. A synthetic Toll-like receptor 2 （TLR2） ligand, Pam3CSK4, has been reported to modulate the balance of Th1/Th2 responses. We evaluated the modulation effect of Pam3CSK4 on allergic immune response in a mouse rhinitis model sensitized to house dust mite allergen （HDM）. Mice were sensitized and challenged with Dermatophagoidesfarinae allergen （Der f）, and then the allergic mice were treated by Pam3CSK4. Nasal allergic symptoms and eosinophils were scored. Der f-specific cytokine responses were examined in the splenocytes and bronchoalveolar lavage fluid （BALF）. Serum level of total IgE was also detected. After establishing a mouse allergic rhinitis model with HDM, we have showed that Pam3CSK4 treatment not only ameliorated the nasal allergic symptoms remarkably but also decreased the eosinophils and total inflammation cells in BALF significantly. Analysis of cytokine profile found that IFN-7 released from either BALF or stimulated splenocytes increased markedly in Pam3CSK4-treated mice, while IL-13 decreased significantly. Moreover, serum level of total IgE was significantly lower in Pam3CSK4-treated mice than in the untreated. Thus, in an allergic rhinitis mouse model developed with HDM, Pam3CSK4 was shown to exhibit an antiallergic effect, indicating its potential application in allergic diseases.

关键词： Toll-like receptor 2 (TLR2) Ligand Allergic immune response Mite allergen

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嵌入式系统的需求描述综述

软件学报 2025年第1期36卷 27-46页

作者：陈小红刘少彬金芝上海市高可信计算重点实验室(华东师范大学) 高可信软件技术教育部重点实验室(北京大学) 北京大学计算机学院

随着嵌入式系统的广泛应用,其需求正变得越来越复杂,需求分析成为嵌入式系统开发的关键阶段,如何准确地建模和描述需求成为首要问题.系统地调研嵌入式系统的需求描述,并进行全面的比较分析,以便更深入地理解嵌入式系统需求的核心关注点... 详细信息

随着嵌入式系统的广泛应用,其需求正变得越来越复杂,需求分析成为嵌入式系统开发的关键阶段,如何准确地建模和描述需求成为首要问题.系统地调研嵌入式系统的需求描述,并进行全面的比较分析,以便更深入地理解嵌入式系统需求的核心关注点.首先采用系统化文献综述方法,对1979年1月–2023年11月间发表的相关文献进行识别、筛选、汇总和分析.通过自动检索和滚雪球等检索过程,筛选出150篇与主题密切相关的文献,力求文献综述的全面性.其次,从需求描述关注点、需求描述维度、需求分析要素等方面,分析现有嵌入式需求描述语言的表达能力.最后,总结现有嵌入式系统软件需求描述所面临的挑战,并针对嵌入式软件智能合成任务,提出对嵌入式系统需求描述方法表达能力的要求.

关键词：嵌入式系统需求描述需求描述语言需求分析系统需求

Surface micro-arrays enhancing electromagnetic interference shielding of polydimethylsiloxane/multiwalled carbon nanotubes nanocomposites

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Nano Research 2025年第1期18卷 508-519页

作者： Ke Jiang zhi chen Ji Yu chen Zheng Shan Huang Ming Wang Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Mechanics Civil Engineering and ArchitecturesNorthwestern Polytechnical UniversityXi’an 710072China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Herein,the electromagnetic shielding performance of surface concave-convex(SC)and zig-zag micro-arrays was studied by using a simulation prediction and a three-dimensional(3D)printing custom ***,surface stripe concaveconvex(SSC)and surface cylindrical concave-convex(SCC)micro-arrays with or without zig-zag micro-arrays are designed,and their shielding performance is simulated in multi-bands(C-,X-band).The multiwalled carbon nanotubes/polydimethylsiloxane composites(MWCNT/PDMS)with different SC structures and different electrical conductivity are molded in acrylonitrile-butadiene-styrene copolymer(ABS)molds which are printed by a 3D *** results show that the electromagnetic interference shielding effectiveness(EMI SE)of the samples can be enhanced by constructing the SC micro-arrays with zig-zag micro-arrays,and improving with the increase of conductivity and *** addition,the shielding mechanism of the SC-MWCNT/PDMS composites is investigated and discussed by an electromagnetic simulation.

关键词： surface micro-arrays electrical properties electromagnetic interference(EMI)shielding three-dimensional(3D)printing

Experimental and theoretical analysis of equilibrium segregation and radiation-induced segregation of Cr at grain boundariesin a reduced activation ferritic/martensitic(RAFM)steel

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Journal of Iron and Steel Research International 2021年第4期28卷 445-452页

作者： Li-dong Xia Hao chen zhi-gang Yang Chi Zhang Key Laboratory of Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Helium ion irradiation at 350℃was performed to study equilibrium segregation and radiation-induced segregation(RIS)of Cr at grain boundaries in reduced activation ferritic/martensitic *** concentration at grain boundary was measured by scanning transmission electron microscopy with an energy-dispersive *** measured Cr concentration at grain boundaries in heat treated zone was 11.7 and 12.8 wt.%in irradiated zone,respectively,which matched well to the calculated results from Mclean and modified Perk *** segregation and RIS of Cr mechanisms were theoretically *** analysis indicates that as temperature rises,equilibrium Cr segregation decreases monotoni-cally,while RIS of Cr has a bell-shape profile,which increases first and then *** is also shown that at low and high temperatures,equilibrium segregation of Cr is higher than that of RIS;at intermediate temperatures,equilibrium Cr segregation is lower than RIS.

关键词： Reduced activation ferritic/martensitic steel Equilibrium Cr segregation Radiation-induced segregation Grain boundary Rate theory Mclean equation

A deep reinforcement learning(DRL)based approach for well-testing interpretation to evaluate reservoir parameters

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Petroleum Science 2022年第1期19卷 264-278页

作者： Peng dong zhi-Ming chen Xin-Wei Liao Wei Yu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing(CUP)Beijing102249China University of Texas at Austin Austin78731TexasUSA

Parameter inversions in oil/gas reservoirs based on well test interpretations are of great significance in oil/gas *** well test interpretations based on artificial intelligence are the most promising to solve the problem of non-unique *** this work,a new deep reinforcement learning(DRL)based approach is proposed for automatic curve matching for well test interpretation,by using the double deep Q-network(DDQN).The DDQN algorithms are applied to train agents for automatic parameter tuning in three conventional well-testing *** addition,to alleviate the dimensional disaster problem of parameter space,an asynchronous parameter adjustment strategy is used to train the ***,field applications are carried out by using the new DRL *** show that step number required for the DDQN to complete the curve matching is the least among,when comparing the naive deep Q-network(naive DQN)and deep Q-network(DQN).We also show that DDQN can improve the robustness of curve matching in comparison with supervised machine learning *** DDQN algorithm to perform 100 curve matching tests on three traditional well test models,the results show that the mean relative error of the parameters is 7.58%for the homogeneous model,10.66%for the radial composite model,and 12.79%for the dual porosity *** the actual field application,it is found that a good curve fitting can be obtained with only 30 steps of parameter adjustment.

关键词： Well testing Deep reinforcement learning Automatic interpretation Parameter evaluation

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苯酐轻组份对合成DOP质量影响的研究

天津化工 2003年第5期17卷 46-47页

作者：吴军石志博陈东山东齐鲁增塑剂股份有限公司山东淄博255411

精苯酐中适量苯酐轻组份的加入 ,对邻苯二甲酸二辛酯 (DOP)产品的APHA色值和体积电阻系数没有影响 ,但会影响纯度。

关键词：苯酐轻组份邻苯二甲酸二辛酯

High-strength Ti-Al-V-Zr cast alloys designed using α and β cluster formulas

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China Foundry 2023年第1期20卷 23-28页

作者： zhi-hao Zhu Yu-han Liu zhi-peng chen Tian-yu Liu Shuang Zhang Dan-dan dong Chuang dong Key Laboratory for Materials Modification by Laser Ionand Electron Beams and School of Materials Science and EngineeringDalian University of TechnologyDalian 116024LiaoningChina State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang Research Institute of Foundry Co.Ltd.Shenyang 110022China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028LiaoningChina College of Physical Science and Technology Dalian UniversityDalian 116622LiaoningChina

Ti-Al-V-Zr quaternary titanium alloys were designed followingα-{[Al-Ti12](AlTi2)}17-n+β-{[Al-Ti12Zr2](V3)}n,where n=1-7(the number ofβunits),on the basis of the dual-cluster formula of popular Ti-6Al-4V *** an alloying strategy aims at strengthening the alloy via Zr and V co-alloying in theβ-Ti unit,based on the originalβformula[Al-Ti14](V2Ti)of Ti-6Al-4V *** microstructures of the as-cast alloys by copper-mold suction-casting change from pureα(n=1)toα+α’martensite(n=7).When n is 6,Ti-5.6Al-6.8V-8.1Zr alloy reaches the highest ultimate tensile strength of 1,293 MPa and yield strength of 1,097 MPa,at the expense of a low elongation of 2%,mainly due to the presence of a large amount of acicularα’*** specific strength far exceeds that of Ti-6Al-4V alloy by 35%.

关键词： titanium alloy cluster-plus-glue-atom model composition design microstructure mechanical properties