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中国力学大会-2021+1

作者： Yang Liu cheng Yang Pingzhang Zhou Jianbin du School of Aerospace Engineering Tsinghua University School of Aerospace Engineering Beijing Institute of Technology

In this paper,a simple and efficient topology optimization method is *** basic idea consists in exploring a combination of density method together with level-set description to form a new optimization *** to level-set description,solutions show clear and smooth boundaries that are deemed more mechanically ***,the checkerboarding issue,usually paired with element description,can be ***,the filter scheme to tackle with this problem becomes unnecessary and the design space can be further *** ingredient of material interpolation with penalty is utilized here and the merit of it is that the update information(***) becomes more distinguished with penalization,which drives the optimization process converging to solid-void solutions *** ordinary differential equation(OdE) that established form optimal criteria builds relationship between level-set description and update information,and the structural updating procedure can be efficiently performed by solving the OdE.A regularization scheme for the levelset is introduced to enhance topological variation ability and address topological evolution defects,which helps in delivering reasonable and well-posed topological *** regularization strategy is a simple linear scaling manner and can be very effective and *** types of optimization problem including compliance minimization,eigenfrequency maximization and heat resistance are *** 2d and 3d benchmark examples in comparison with the widely accepted SIMP method are tested to validate the proposed *** contrast,solutions resulted from the proposed method show advantageous structural representations and better objective function values under specified *** addition,several other numerical examples considering algorithm parameter influences and some extensions are discussed to systematically demonstrate characteristics of the proposed method.

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Hepatitis C Virus-induced upregulation of miR-155 promotes hepatocarcinogenesis by activating Wnt signaling

Hepatitis C Virus-induced upregulation of miR-155 promotes h...

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第十二次全国医学遗传学学术会议

作者： Yiliang Zhang Wei Wei Na cheng Shuhan Sun department of Medical Genetics Secondary military medicine university

Background & Aims:Hepatitis C virus(HCV) infection usually induces chronic hepatic inflammation,which favors the initiation and progression of hepatocellular carcinoma. Moreover,microRNA-155(miR-155) plays an important role in regulating both inflammation and ***,little is known about whether and how miR-155 provides the link between inflammation and *** & Results:In this study,we found that miR-155 levels were markedly increased in patients infected with ***-155 transcription was regulated by NF-κB,and p300 increased NF-κB-dependent miR-155 *** overexpression of miR-155 significantly inhibited hepatocyte apoptosis and promoted cell proliferation,whereas miR-155 inhibition induced G0/G1 *** miR-155 resulted in nuclear accumulation ofβ-catenin and a concomitant increase in cyclin d1,c-myc and survivin. Gain-of-function and loss-of-function studies demonstrated that miR-155 promoted hepatocyte proliferation and tumorigenesis by increasing Wnt signaling in vitro and in vivo,and dKK1(Wnt pathway inhibitor) overexpression inhibited the biological role of miR-155 in ***, adenomatous polyposis coli(APC),which negatively regulates Wnt signaling,was identified as the direct and functional target of ***:HCV-induced miR-155 expression promotes hepatocyte proliferation and tumorigenesis by activating Wnt *** present study provides a better understanding of the relationship between inflammation and tumorigenesis, and thus may be helpful in the development of effective diagnosis and treatment strategies against HCV-HCC.

关键词： HCV HCC miR-155 Wnt Apc.

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Identification of antioxidant activity of two new aromatic ring butyrolactone derivatives from dictamnus dasycarpus Turcz

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Chinese Journal of Natural Medicines 2016年第11期14卷 876-880页

作者： GUO Li-Na PEI Yue-Hu XIE Fei-Xiang LIU Lei CONG Huan CUI Hong-Xia WANG Xiao-Li LI Wen-Jing JIAN Bai-Yu LIU Ji-cheng School of Pharmacy Qiqihar Medical University School of Traditional Chinese Medicine Shenyang Pharmaceutical University

The present study carried out a phytochemical investigation on the root barks of dictamnus dasycarpus Turcz, leading to the isolation and characterization of two new aromatic ring butyrolactone derivatives, dasycarpusphenol acid A(1) and dasycarpusphenol acid B(2). Their structures were elucidated by using spectroscopic techniques and HR-FAB-MS. Compounds 1 and 2 exhibited antioxidant activity, with their IC_(50) values being 28.95 and 41.76 mg·mL^(-1),respectively.

关键词： dasycarpusphenol acid A dasycarpusphenol acid B dictamnus dasycarpus Antioxidant activity

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氮肥和容器深度对栓皮栎容器苗生长、根系结构及养分贮存的影响

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林业科学 2016年第4期52卷 21-29页

作者：程中倩李国雷北京林业大学省部共建森林培育与保护教育部重点实验室城乡生态环境北京实验室北京100083

【目的】氮肥施用量或容器深度可有效调控苗木质量,本研究同时采用2种措施培育容器苗,探讨2种措施对苗木质量提升的叠加效应,为丰富苗木质量调控措施提供参考。【方法】以1年生栓皮栎容器苗为试验材料,采用双因素完全随机试验设计,设置... 详细信息

【目的】氮肥施用量或容器深度可有效调控苗木质量,本研究同时采用2种措施培育容器苗,探讨2种措施对苗木质量提升的叠加效应,为丰富苗木质量调控措施提供参考。【方法】以1年生栓皮栎容器苗为试验材料,采用双因素完全随机试验设计,设置2个施肥水平(100 mg N·株^(-1))及2个容器深度(25,36 cm),通过测定第1年生长季末栓皮栎苗高、地径、生物量、养分浓度以及不同径级根系体积、表面积、长度。【结果】施氮肥与容器长度交互效应对根氮浓度和中等径级根系(2~3 mm)的根体积、表面积显著,25 mg N-36 cm组合有利于中等根系径级生长,100 mg N-36 cm组合有利于根系氮浓度提高,这表明交互效应对地下部分的影响大于地上,2种措施交互作用通过影响根系来调控苗木质量。主效应表明,充足施肥量有利于地径生长、根氮和钾浓度提高;容器长度对根系结构的影响较施氮量显著,深容器可促进根系径级为3~4 mm的根系发育,否则造成窝根;长容器可促进苗高生长、茎生物量积累以及茎氮浓度提高。【结论】苗木生长、养分、根系结构对施氮量与容器深度的交互效应与主效应响应规律证实2种措施相结合调控苗木质量的必要性。主根发达树种栓皮栎容器苗最佳组合为100 mg N和36 cm深的容器。

关键词：容器苗氮肥容器深度根系结构苗木生长养分浓度

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频谱分解及地质模型反演新方法在滩坝砂沉积特征及发育模式研究中的应用

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中国石油大学学报（自然科学版） 2013年第3期37卷 37-43页

作者：郭建卿林承焰中国石油大学地球科学与技术学院山东青岛266580

基于研究区三维高精度地震资料,根据地震沉积学原理,利用频谱分解、地震反演等岩性地球物理技术,并结合地质、测井、录井资料,对博兴油田沙四上亚段滩坝砂储层进行有效预测。结果表明:30 Hz为最佳调谐频率值;沙四上中部砂体最发育,沉积... 详细信息

基于研究区三维高精度地震资料,根据地震沉积学原理,利用频谱分解、地震反演等岩性地球物理技术,并结合地质、测井、录井资料,对博兴油田沙四上亚段滩坝砂储层进行有效预测。结果表明:30 Hz为最佳调谐频率值;沙四上中部砂体最发育,沉积特征较为显著;滩坝砂经历了一次明显'湖退砂进'的沉积演化过程;研究区滩坝砂沉积模式呈湖退进积'坝'砂沉积为主,湖进退积'滩'砂、浅湖泥沉积为主的特征;滩坝砂沉积主要控制因素为水动力作用和古地形条件等。

关键词：滩坝砂频谱分解地震反演单频切片储层预测

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Societal response to challenges of global change and human sustainable development

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Chinese Science Bulletin 2013年第21期58卷 3161-3168页

作者： XU GuanHua GE QuanSheng GONG Peng FANG XiuQi cheng BangBo HE Bin LUO Yong XU Bing Ministry of Science and Technology the People's Republic of China Institute of Geographical Science and Resource Research Chinese Academy of Sciences Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University College of Geography and Remote Sensing Beijing Normal University College of Global Change and Earth System Science Beijing Normal University College of Environmental Science and Engineering Tsinghua University

It is now widely accepted that carbon emission from human activities is an important driving force in global warming, and global change has a deep impact on sustainable development of human society. To meet the challenges of global change, the international community has reached a consensus that developed countries take strict actions in emission reduction, whereas developing countries take spontaneous efforts in reducing emissions under the guiding principle of common but differentiated responsibilities, with an agreed goal to restrict global surface temperature increase due to human activities to within 2℃ of pre-industrial levels. However, there is no clear pathway to reach this goal. A number of related questions must be addressed on principles to be followed, research emphasis and policy measures. Here we argue that response policies to address global change issues must be based on balanced development at regional and international levels, and on advancements in science and technology. This requires consideration of harmony not only between humans and nature but also within human societies, to properly deal with the relationship between global change and sustainable development. We must make equal efforts toward carbon emission reduction and carbon sequestration, and toward mitigation and adaptation. There should be more research support to reduce uncertainties in our understanding of global change. Addressing the challenges of global change creates great opportunities for the development of human society. This will facilitate transformation of energy use structure, improve and restore ecological functioning of the earth environment, transform production modes and ways of living in human society, and promote harmonic and balanced development at regional and international levels.

关键词：人类可持续发展人类社会全球变化全球气候变化国际社会人类活动均衡发展发展中国家

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可见光车灯信号发送控制装置

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光学精密工程 2020年第12期28卷 2710-2718页

作者：邓健志程小辉桂林理工大学信息科学与工程学院广西桂林541004 桂林理工大学广西嵌入式技术与智能系统重点实验室广西桂林541004

针对车联网中的通信需求,本文提出了一种即插即用的可见光车灯信号发送控制装置。装置利用车灯低压直流供电线路进行信号传输,并通过车灯发送可见光通信信号。装置前级将接收的输入信号,由高速开关电路控制线路的供电通断,从而将通信信... 详细信息

针对车联网中的通信需求,本文提出了一种即插即用的可见光车灯信号发送控制装置。装置利用车灯低压直流供电线路进行信号传输,并通过车灯发送可见光通信信号。装置前级将接收的输入信号,由高速开关电路控制线路的供电通断,从而将通信信号传导至后级并由后级控制LEd车灯发送可见光信号。通过推导和实验选用电容作为线路储能器件,并采用2FSK调制和Modbus协议建立前后级间通信。实验证明装置可以利用线路实现最快不低于4 Mb/s的信号传输,并通过可见光车灯控制地锁的实验模型,进一步验证了该装置接收信号并通过低压直流供电线路控制车灯发送可见光信号的功能。本设计为利用直流供电线路传输信息并点亮的LEd灯实现可见光通信,提供了参考设计模型。

关键词：直流电力线通信可见光通信 LEd通信车地通信车联网

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深冻结井筒内层钢板高强钢筋混凝土复合井壁试验研究

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岩石力学与工程学报 2008年第1期27卷 153-160页

作者：姚直书程桦荣传新安徽理工大学土木工程系安徽淮南232001

针对600～800 m特厚表土层中冻结井筒的支护难题,根据约束混凝土原理,提出合理的解决途径是采用内层钢板高强钢筋混凝土复合冻结井壁结构。通过模型试验,对该种井壁结构的应力、变形和强度特性进行深入研究,结果表明:由于内层钢板筒的... 详细信息

针对600～800 m特厚表土层中冻结井筒的支护难题,根据约束混凝土原理,提出合理的解决途径是采用内层钢板高强钢筋混凝土复合冻结井壁结构。通过模型试验,对该种井壁结构的应力、变形和强度特性进行深入研究,结果表明:由于内层钢板筒的约束作用,井壁结构中混凝土处于三轴受压应力状态下,其变形能力和抗压强度都得到较大程度的提高,井壁破坏时,内缘混凝土的环向应变可达-4 000με,表现出较好的延性特性,改善了高强混凝土的脆性缺陷。如将目前现场使用的现浇高强钢筋混凝土冻结井壁改为内层钢板高强钢筋混凝土复合结构形式,则井壁承载能力可大大提高,可合理地解决特厚表土层中冻结井筒的支护难题。影响该种井壁极限承载力大小的因素依次为混凝土抗压强度、厚径比、内层钢板厚度和配筋率,其中提高混凝土强度对井壁承载力影响非常显著,如将混凝土强度提高10 MPa,则井壁承载力将提高约13.8%。而增大配筋率对井壁承载力影响甚微,所以,在实际工程应用中,为经济合理设计井壁,只需配置单外排钢筋。最后,根据理论分析和试验结果推导出该种井壁承载力的计算公式,从而为该种井壁结构的工程应用提供设计依据。

关键词：采矿工程特厚表土层冻结井壁内层钢板筒高强钢筋混凝土模型试验

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Complexity Reduction of the Received Signal in the Presence of Multipath

Complexity Reduction of the Received Signal in the Presence ...

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第37届中国控制会议

作者： Kai Wang Lan cheng Xinying Xu dengao Li College of Electronical and Power Engineering Taiyuan University of Technology College of Big data Taiyuan University of Technology

Multipath elimination is one of the main research topics in high-precision positioning systems. Existing multipath elimination algorithms are affected by the received signal data size to a large extent in terms of algorithm complexity. The conventional signal size reduction method based on auto-correlation function is influenced not only by sample frequency but also by coherent interval. Furthermore, it also limits the multipath elimination algorithms that can be used in post processing. To address these problems, three signal reduction algorithms, canonical components（CC）-based method, principle component（PC）-based method and the combination method of CC and PC, are analyzed comprehensively from the prospective of relative energy error and signal size. To improve the real-time performance of the PC method, the fast-PC method is proposed. Meanwhile, the suggested correlation number and correlation spacing are also discussed in this paper. The simulation results show that the combination method of CC and PC outperforms other methods and can reduce the signal size efficiently, which means that it can offer a smaller size source signal for the multipath elimination algorithms used in the post processing.

关键词： Multipath elimination Canonical components Principal components Relative energy error

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Responses of ground-dwelling spiders to four hedgerow species on sloped agricultural fields in Southwest China

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Progress in Natural Science:Materials International 2009年第3期19卷 337-346页

作者： Yuhong Wu a, Qingnian Cai b, Chaowen Lin c, Yibing Chenc, Yuying Lid, Xu cheng b,* a College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China b College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, China c Institute of Soils and Fertilizers, Sichuan Academy of Agricultural Sciences, chengdu 610066, China d College of Life Science and Technology, Nanyang Normal University, Nanyang 473061, China College of Resources and Environmental Sciences China Agricultural University Beijing 100193 China College of Agriculture and Biotechnology China Agricultural University Beijing 100193 China Institute of Soils and Fertilizers Sichuan Academy of Agricultural Sciences Chengdu 610066 China College of Life Science and Technology Nanyang Normal University Nanyang 473061 China

Spiders are important predators in agroecosystems and contribute to the control of agricultural pest populations. Habitat manage- ment such as the creation of new semi-natural habitats around or within fields enhances spider abundance and species diversity. Using pitfall traps, we investigated the effects of four hedgerow plant species, which serve as undisturbed and permanent semi-natural habitats, on ground-dwelling spider activity density (a parameter of population density and relative activity) and species richness. Samples were collected over two winter wheat and two summer maize growing seasons during 2005-2007 in trial field 1 (slope gradient of 20%) and field 2 (slope gradient of 12%) at the Ziyang Experimental Site in Sichuan Province, China. The hedgerow species evaluated were Amorpha fruticosa (field 1), Vetiveria zizanioides (field 1), Eulaliopsis binata (field 2), and Medicago sativa (field 2). Compared to control plots, hedgerow plots had significantly higher activity density and species richness of ground-dwelling spiders within strips in both fields 1 and 2 during the wheat growing season. The presence of hedgerow strips did not augment the activity density and species richness of ground-dwelling spiders within the crop fields during the wheat or maize growing seasons. The ground-dwelling spider activity density within hedgerow strips was significantly higher in the Vetiveria than in the Amorpha plots and in the Medicago than in the Eulaliopsis plots, and the species richness was significantly higher in the Vetiveria than in the Amorpha plots during the wheat season. Our results suggest that hedgerows may serve as important overwintering sites for ground-dwelling spiders during the wheat growing season. In addition, the diversification of agroecosystems by using hedgerow strips may be a viable strategy for maintaining ground-dwelling spider populations in agricultural areas. However, ground-dwelling spiders did not move into adjacent crop fields; the

关键词： Activity density Araneae Ground-dwelling Hedgerow Pitfall trapping Species richness

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