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Theory and method of mechanism system design

Huijun ZOU, Qinghua LIANG, Qing ZHANG

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 399-411 doi: 10.1007/s11465-010-0116-8

摘要： Conceptual design is the most critical and creative phase of design. Recently, increasing attention has been directed to supporting conceptual-level computer aided creative design and its theories and methodologies. Specifically, for conceptual design of mechanical products, this paper presents a novel function solving model for mechanical product design and highlights the importance of systematic synthesis to achieve creative design. Then it builds a framework as a function-effect-process-action- mechanisms (FEPAM) mapping process, which enables creative design on the basis of conceiving different action schemes. After that, several key points are elaborated including 1) representing and decomposition methods of functions and motion behaviors; 2) action scheme representing method based on network plan techniques; and 3) variation and creation methods based on action scheme transformations.

关键词： mechanism system creative design     process model     function solving model     process action procedure     mechanisms knowledge base     principle of mechanism system composition    

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Discovery of cryptolepine derivatives as novel promising agents against phytopathogenic bacteria

《化学科学与工程前沿（英文）》 2023年 第17卷 第2期   页码 156-166 doi: 10.1007/s11705-022-2196-5

摘要： To ensure the production of food crops, a series of cryptolepine derivatives were synthesised, after which their antibacterial activities and mechanism of action against three plant pathogens were investigated. Our bioassay results indicated that most of the target compounds displayed potent inhibitory effects against Xanthomonas oryzae (X. oryzae) and Xanthomonas axonopodis pv. citri (X. axonopodis pv. c.). Remarkably, compound 9 exhibited the best in vitro antibacterial activity against X. oryzae, with a minimum inhibitory concentration (MIC) value of 0.78 μg·mL–1. Compound 2 exhibited the best in vitro antibacterial activity against X. axonopodis pv. c., with an MIC value of 0.39 μg·mL–1. These activities were superior to those of copper quinolate (MIC = 6.25, 25 μg·mL–1) and thiodiazole copper (MIC = 100, 200 μg·mL–1) against X. oryzae and X. axonopodis pv. c. In vivo experiments demonstrated the promising applicability of compound 9 for the control of rice bacterial infections. Furthermore, compound 9 was selected as a candidate to conduct preliminary analyses of the antibacterial mechanisms of cryptolepine derivatives. Scanning electron microscopy and transmission electron microscopy observations, extracellular polysaccharide production, biofilm formation, transcriptomic, quantitative reverse transcription-polymerase chain reaction analyses, and molecular docking assays were performed. Collectively, our findings demonstrated that compound 9 might act via multifarious mechanisms to down-regulate virulence factors and cause cell death.

关键词： cryptolepine derivatives     phytopathogenic bacteria     antibacterial activity     mechanism of action    

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Evaluation of 1,4-naphthoquinone derivatives as antibacterial agents: activity and mechanistic studies

《环境科学与工程前沿（英文）》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1631-2

摘要：

● All 1,4-naphthoquinone hybrids exhibited significant antimicrobial activity.

关键词： 1     4-naphthoquinone derivatives     Antibacterial     Action mechanism     RecA    

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Influence of construction-induced damage on the degradation of freeze–thawed lightweight cellular concrete

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 781-792 doi: 10.1007/s11709-021-0733-9

摘要： During the construction of lightweight cellular concrete (LCC), material damage frequently occurs, causing the degradation and deterioration of the mechanical performance, durability, and subgrade quality of LCC. The construction-induced damage can be more significant than those from the service environment of LCC, such as freeze–thaw (F–T) action in cold regions. However, the effect of construction-induced damage on LCC during F–T cycles is often ignored and the deterioration mechanisms are not yet clarified. In this study, we investigated the factors causing damage during construction using a sample preparation method established to simulate the damage in the laboratory setting. We conducted F–T cycle tests and microstructural characterization to study the effect of microstructural damage on the overall strength of LCC with different water contents under F–T actions. We established the relationship between the pore-area ratio and F–T cycle times, pore-area ratio, and strength, as well as the F–T cycle times and strength under different damage forms. The damage evolution is provided with the rationality of the damage equation, verified by comparing the measured and predicted damage variables. This study would serve as a guide for the construction and performance of LCC in cold regions.

关键词： lightweight cellular concrete     construction-induced damage     freeze-thaw action     microstructure     degradation mechanism    

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View-invariant human action recognition via robust locally adaptive multi-view learning

Jia-geng FENG,Jun XIAO

《信息与电子工程前沿（英文）》 2015年 第16卷 第11期   页码 917-920 doi: 10.1631/FITEE.1500080

摘要： Human action recognition is currently one of the most active research areas in computer vision. It has been widely used in many applications, such as intelligent surveillance, perceptual interface, and content-based video retrieval. However, some extrinsic factors are barriers for the development of action recognition; e.g., human actions may be observed from arbitrary camera viewpoints in realistic scene. Thus, view-invariant analysis becomes important for action recognition algorithms, and a number of researchers have paid much attention to this issue. In this paper, we present a multi-view learning approach to recognize human actions from different views. As most existing multi-view learning algorithms often suffer from the problem of lacking data adaptiveness in the nearest neighborhood graph construction procedure, a robust locally adaptive multi-view learning algorithm based on learning multiple local L1-graphs is proposed. Moreover, an efficient iterative optimization method is proposed to solve the proposed objective function. Experiments on three public view-invariant action recognition datasets, i.e., ViHASi, IXMAS, and WVU, demonstrate data adaptiveness, effectiveness, and efficiency of our algorithm. More importantly, when the feature dimension is correctly selected (i.e.,>60), the proposed algorithm stably outperforms state-of-the-art counterparts and obtains about 6% improvement in recognition accuracy on the three datasets.

关键词： View-invariant     Action recognition     Multi-view learning     L1-norm     Local learning    

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China released the Action Plan on Prevention and Control of Soil Pollution

Fang Zhang,Guanghe Li

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0867-5

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Effect of mineral additives and permeability reducing admixtures having different action mechanisms on

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1277-1291 doi: 10.1007/s11709-021-1752-2

摘要： In this paper, the effect of usage of the permeability reducing admixture (PRA) having different action mechanisms on hardened state properties of cementitious systems containing mineral additives is examined. For this aim, three commercial PRAs were used during investigation. The effective parameters in the first and third PRAs were air-entraining and high-rate air-entraining, respectively. The second one contained the insoluble calcium carbonate residue and had a small amount of the air-entraining property. Mortar mixes with binary and ternary cementitious systems were prepared by partially replacing cement with fly ash and metakaolin. The hardened state properties of mortar mixtures such as compressive strength, ultrasonic pulse velocity, water absorption, drying shrinkage and freeze–thaw resistance were investigated. The ternary cement-based mixture having both fly ash and metakaolin was selected as the most successful mineral-additive bearing mix in regard to hardened state properties. In this sense, PRA-B, with both insoluble residues and a small amount of air-entraining properties, showed the best performance among the mixtures containing PRA. The combined use of mineral additive and PRA had a more positive effect on the properties of the mixes.

关键词： cementitious system     mineral additive     permeability reducing admixture     mechanical properties     durability performance    

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青蒿素——一种从中药中发现的神奇药物 Review

王继刚, 徐承超, 王彦钧, 李玉洁, 廖福龙, 姜廷良, 屠呦呦

《工程（英文）》 2019年 第5卷 第1期   页码 32-39 doi: 10.1016/j.eng.2018.11.011

摘要：

青蒿素及其衍生物是治疗疟疾最重要且最具影响力的一类药物。自20世纪70年代初发现青蒿素以来，国际上在研究这种非凡的植物化学药物及探明其独特的化学和药理特性方面取得了巨大进展。现今，虽然青蒿素及其衍生物仍然是抗疟的支柱药物，它们的持续应用和发展也面临许多挑战。这些挑战包括青蒿素治疗疟疾过程中出现的耐药现象以及青蒿素在其它疾病中的应用。在这篇综述中，我们描述了青蒿素类药物的早期发现和发展过程、应用现状以及未来的发展前景。另外，我们总结了当前的青蒿素机制研究情况并提出了我们自己的看法，同时强调了机制研究对于青蒿素类药物在抗疟以及其它疾病治疗中的重要性。

关键词： 青蒿     作用机制     疟疾     抗癌    

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Study on the action of resistin-induced human umbilical vein endothelial cell dysfunction

LI Zhizhen, LI Fangping, YAN Li, LI Feng, LI Yan, CHENG Hua, FU Zuzhi

《医学前沿（英文）》 2007年 第1卷 第2期   页码 196-199 doi: 10.1007/s11684-007-0037-z

摘要： The aim of this paper was to investigate the effects of resistin on human umbilical vein endothelial cells (HUVECs), and to explore its role and mechanism of action in atherosclerosis. HUVECs were incubated with recombinant human resistin (0, 50, 100 ng/mL) for 24 h. ICAM-1, VCAM-1 and reactive oxygen species (ROS) were assayed by flow cytometer. ET-1, eNOS and iNOS mRNA expression were measured by semi-quantitative RT-PCR. Incubation of HUVECs with resistin resulted in an increase in ICAM-1 expression and ET-1 mRNA expression. However, resistin had no effect on VCAM-1 expression and ROS release. eNOS and iNOS mRNA expression were not altered by resistin stimulation. Adipokine resistin exerted a direct effect in promoting HUVEC dysfunction by promoting ICAM-1 and ET-1 expression. These data suggest that adipocyteendothelium cross-talk might play an important role in the pathogenesis of cardiovascular disease in diabetes mellitus.

关键词： endothelial     resistin stimulation     Incubation     pathogenesis     dysfunction    

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Emerging contaminant control: From science to action

《环境科学与工程前沿（英文）》 2022年 第16卷 第6期 doi: 10.1007/s11783-022-1559-y

摘要： Since the concept of emerging contaminants (ECs) was first proposed in 2001, the global scientific research of ECs has developed rapidly. In the past decades, great progress has been achieved in the scientific research of ECs in China, including the establishment of EC analysis method system, the evaluation of the pollution status, pollution characteristics and environmental risk of ECs in typical regions of China, and establishment of EC control technology system. Continuous progress in scientific research of ECs promoted China’s action on EC control. It is planned that the environmental risk of ECs will be generally controlled by 2035 in China. Priority ECs should be screened for environmental management. Although great efforts have been made, the EC control in China still faces tremendous challenges. It is necessary to bridge the gap between scientific research and decision-making management. Based on the science and technology study, various measures such as engineering, policy management and public participation should be combinedly adopted for EC control.

关键词： Emerging contaminants     Priority pollutants     PPCPs     POPs     Control policy    

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Study of the mechanics of progressive collapse of FPB isolated beam-pier substructures

Jingcai ZHANG; Yong DING; Xinchun GUAN

《结构与土木工程前沿（英文）》 2022年 第16卷 第6期   页码 718-728 doi: 10.1007/s11709-022-0815-3

摘要： The horizontal stiffness of the isolated layer is reduced substantially by a friction pendulum bearing (FPB) toprotectthe structure from potential damages caused by earthquakes. However, horizontal stiffness is essential to progressive collapse resistance of structures. This paper presents a simplified model to assess the progressive collapse response of beam-pier substructure isolated by FPB. Progressive collapse resistance by flexural action of the beam and additional resistance owing to the horizontal restraining force was achieved. The influences of the equivalent radius and friction coefficient of the FPB, the applied axial force on the FPB, and span-depth ratio of the beam on the additional resistance were investigated. Simulations were conducted to verify the proposed model. The results show that progressive collapse resistance provided by horizontal restraining can be reduced as large as 46% and 88% during compressive arching action (CAA) and catenary action (CA), respectively. The equivalent radius of the FPB shows limited effect on the progressive collapse response of FPB isolated structures, but friction coefficient and applied axial force, as well as depth ratio of the beam, show significant influences on the additional progressive collapse resistance capacity. Finite element method (FEM) results are in good agreement with the result obtained by the proposed method.

关键词： friction pendulum bearing     progressive collapse     horizontal stiffness     compressive arching action     catenary action    

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中国工程院推出“院士行动”计划

《中国工程科学》 1999年 第1卷 第1期   页码 107-107

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“互联网 +”行动计划的政策体系研究

陈磊,王柏村,黄思翰,姚磊,边大成,范鑫

《中国工程科学》 2020年 第22卷 第4期   页码 131-138 doi: 10.15302/J-SSCAE-2020.04.003

摘要：

“互联网 +”行动计划对推动我国产业升级和经济高质量发展具有重要意义，随着“互联网 +”迈向深度发展阶段、关联技术不断升级、新模式和新业态持续涌现，亟需总结发展现状并梳理面临的问题，以促进相应政策体系的调整完善。本文系统梳理国家、地方层面推进“互联网 +”的政策和规划以明晰当前政策发展现状，凝练“互联网 +”政策供给的主要问题，包括政策文件碎片化现象突出、地方政策文件同质化情况普遍、宏观政策的配套措施不具体、阶段性评估机制缺失。研究提出，在后续推进“互联网 +”发展的政策方面，需要健全“互联网 +”政策制定的系统化机制、完善高效协同的“互联网 +”政策推进工作机制、丰富对“互联网 +”行动的财政税收金融支持方式、建立“互联网 +”法律法规和标准规范体系。相关研究可为我国“互联网 +”行动计划的政策研究提供参考。

关键词： 互联网 +     政策体系     政策供给     完善措施    

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吖啶– 核定位序列偶联构建的高活性抗菌肽 Artical

Wei Zhang,Xiaoli Yang,Jingjing Song,Xin Zheng,Jianbo Chen,Panpan Ma,Bangzhi Zhang,Rui Wang

《工程（英文）》 2015年 第1卷 第4期   页码 500-505 doi: 10.15302/J-ENG-2015106

摘要：

多重耐药菌的出现迫切需要发现具有新作用机制的抗生素。在本研究中，笔者将疏水的吖啶分子连接到核定位序列 (NLS) 的N末端合成了一种新型的抗菌药物Acr3-NLS。为了进 一步提高该试剂的抗菌活性，笔者将两个单体Acr3-NLS分子通过二硫键连接合成了二聚体(Acr3-NLS)2。结果显示，与NLS相比，Acr3-NLS，特别是(Acr3-NLS)2，对革兰阴性菌和革兰阳性菌表现出显著的抗菌活性。随后，其作用机制的研究表明，Acr3-NLS 和(Acr3-NLS)2 可通过细胞膜破坏方式和DNA 结合方式杀死细菌。作用于细胞膜和细胞内DNA的双靶点抑杀机制可以降低细菌对Acr3-NLS 和(Acr3-NLS)2 产生耐药性的风险。总之， 本研究提供了一种新的策略，可用于设计具有双重作用机制的高效抗菌药物。

关键词： 吖啶     核定位序列     共轭连接     抗菌活性     作用机制    

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Initiation and propagation laws of the glass cracks in specimens subjected to normal loading under the action

WAN Zhen-ping, LIU Ya-jun, TANG Yong, YE Bang-yan

《机械工程前沿（英文）》 2006年 第1卷 第2期   页码 194-198 doi: 10.1007/s11465-005-0011-x

摘要： With more and more applications of glass in advanced fields of science, the demand for glass machining precision has increased greatly. More and more attention is being paid to glass cutting because precise glass parts with various shapes can be obtained at high efficiency and low cost. To improve the machining precision of part surfaces and to facilitate tool design and cutting parameter selection, the initiation and propagation laws of glass cracks in specimens subjected to normal loading by symmetric wedges were investigated. Research results show that initiation and propagation laws are the same with interior symmetric wedge angles of 30o-120o, while the laws are different with interior symmetric wedge angles equal to or more than "e150o. The relationship between medial crack length and normal loading was also investigated when specimens were indented by symmetrical wedges with interior angles of 30o-120o.

关键词： different     30o-120o     relationship     initiation     cutting parameter    

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标题 作者 时间 类型 操作

Theory and method of mechanism system design

Huijun ZOU, Qinghua LIANG, Qing ZHANG

期刊论文

Discovery of cryptolepine derivatives as novel promising agents against phytopathogenic bacteria

期刊论文

Evaluation of 1,4-naphthoquinone derivatives as antibacterial agents: activity and mechanistic studies

期刊论文

Influence of construction-induced damage on the degradation of freeze–thawed lightweight cellular concrete

期刊论文

View-invariant human action recognition via robust locally adaptive multi-view learning

Jia-geng FENG,Jun XIAO

期刊论文

China released the Action Plan on Prevention and Control of Soil Pollution

Fang Zhang,Guanghe Li

期刊论文

Effect of mineral additives and permeability reducing admixtures having different action mechanisms on

期刊论文

青蒿素——一种从中药中发现的神奇药物

王继刚, 徐承超, 王彦钧, 李玉洁, 廖福龙, 姜廷良, 屠呦呦

期刊论文

Study on the action of resistin-induced human umbilical vein endothelial cell dysfunction

LI Zhizhen, LI Fangping, YAN Li, LI Feng, LI Yan, CHENG Hua, FU Zuzhi

期刊论文

Emerging contaminant control: From science to action

期刊论文

Study of the mechanics of progressive collapse of FPB isolated beam-pier substructures

Jingcai ZHANG; Yong DING; Xinchun GUAN

期刊论文

中国工程院推出“院士行动”计划

期刊论文

“互联网 +”行动计划的政策体系研究

陈磊,王柏村,黄思翰,姚磊,边大成,范鑫

期刊论文

吖啶– 核定位序列偶联构建的高活性抗菌肽

Wei Zhang,Xiaoli Yang,Jingjing Song,Xin Zheng,Jianbo Chen,Panpan Ma,Bangzhi Zhang,Rui Wang

期刊论文

Initiation and propagation laws of the glass cracks in specimens subjected to normal loading under the action

WAN Zhen-ping, LIU Ya-jun, TANG Yong, YE Bang-yan

期刊论文