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Two Labdane Diterpenes from Leonurus heterophyllus

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Chinese Chemical Letters 2006年第10期17卷 1321-1324页

作者： xian ZHANG Guo Ping peng School of Pharmacy Shanghai University of Traditional Chinese Medicine Shanghai 201203 Botanical Refinement Engineering Research Center Nanjing University-of Traditional Chinese Medicine Nanjing 210029

Two new labdane diterpenoids named heteronone A （1） and heteronone B （2） were isolated from the aerial parts of Leonurus heterophyllus Sweet. Their structures were established by various spectroscopic means, and t... 详细信息

关键词： Labdane diterpenes leonurus heterophyllus Sweet. X-ray diffraction analysis

Projected changes in Köppen-Trewartha climate zones under 1.5-4℃global warming targets over mid-high latitudes of Northern Asia using an ensemble of RegCM4 simulations

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Advances in Climate Change Research 2024年第2期15卷 185-196页

作者： jie WU Xue-jie GAO xian-Bing TANG Filippo GIORGI School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China The Abdus Salam International Centre for Theoretical Physics Trieste 34100Italy

Mid-high latitude Northern Asia is one of the most vulnerable and sensitive areas to global warming,but relatively less studied *** used an ensemble of a regional climate model(RegCM4)projections to assess future changes in surface air temperature,precipitation and Köppen-Trewartha(K-T)climate types in Northern Asia under the 1.5-4℃global warming ***4 is driven by five CMIP5 global models over an East Asia domain at a grid spacing of 25 *** of the present day(1986-2005)simulations shows that the ensembles of RegCM4(ensR)and driving GCMs(ensG)reproduce the major characters of the observed temperature,precipitation and K-T climate zones reasonably *** and more realistic spatial detail is found in RegCM4 compared to the driving GCMs.A general warming and overall increases in precipitation are projected over the region,with these changes being more pronounced at higher warming *** projected warming by ensR shows different spatial patterns,and is in general lower,compared to ensG in most months of the year,while the percentage increases of precipitation are maximum during the cold *** future changes in K-T climate zones are characterized by a substantial expansion of Dc(temperature oceanic)and retreat of Ec(sub-arctic continental)over the region,reaching∼20%under the 4℃warming *** most notable change in climate types in ensR is found over Japan(∼60%),followed by Southern Siberia,Mongolia,and the Korean Peninsula(∼40%).The largest change in the K-T climate types is found when increasing from 2 to 3℃.The results will help to better assess the impacts of climate change and in implementation of appropriate adaptation measures over the region.

关键词： Mid-high latitudes of Northern Asia Köppen climate zones Global warming targets Regional climate model

Distributed Gradient Tracking Methods with Finite Data Rates

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Journal of Systems Science & Complexity 2021年第5期34卷 1927-1952页

作者： MA Xiaoyu YI peng CHEN jie Department of Control Science and Engineering Tongji UniversityShanghai 200082China. Shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai 200082China

This paper studies the distributed optimization problem over an undirected connected graph subject to digital communications with a finite data rate,where each agent holds a strongly convex and smooth cost *** agents need to cooperatively minimize the average of all agents’cost *** agent builds an encoder/decoder pair that produces transmitted messages to its neighbors with a finite-level uniform quantizer,and recovers its neighbors’states by a recursive decoder with received quantized *** the adaptive encoder/decoder scheme with the gradient tracking method,the authors propose a distributed quantized *** authors prove that the optimization can be achieved at a linear rate,even when agents communicate at 1-bit data *** examples are also conducted to illustrate theoretical results.

关键词： Distributed optimization gradient tracking method quantization

A Novel Text Retrieval Algorithm for Public Crisis Cases

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Chinese Journal of Electronics 2019年第4期28卷 712-717页

作者： peng Yan WANG jie JIAO Lulin School of Management Capital Normal University

Public crisis has the characteristics of suddenness and uncertainty, and it is necessary to combine the knowledge with the experience of other similar situations to make decisions effectively and *** work combines artificial intelligent theory with information technology and brings case-based reasoning to build models consisting of the features of public crisis. We explore the case-representation approach and build a case-based retrieval algorithm. Combining the specificness of Case-based reasoning(CBR) technology in the monitoring of public crisis events, a new case retrieval algorithm for public crisis cases, named as Combined multi-similarity with set of simi-larity matching algorithm based on sememe(CMSBS), is proposed to analyze the cases with high similarity to current *** CMSBS algorithm considers the structural and semantic similarities between two public crisis cases comprehensively. Simulation experiments are performed to validate the representation method of the knowledge,and the simulation results demonstrate that the CMSBS algorithm has superior performance in the average number of matching cases and matching accuracy rate and can work well in providing reference cases for subsequent events.

关键词： Knowledge representation Case retrieval Public crisis Case-based reasoning

Failure mechanism and influencing factors of cement sheath integrity under alternating pressure

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Petroleum Science 2023年第4期20卷 2413-2427页

作者： Kuan-Hai Deng Nian-Tao Zhou Yuan-Hua Lin Yan-xian Wu jie Chen Chang Shu peng-Fei Xie State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Southwest Petroleum University) ChengduSichuan610500China Engineering Technology Research Institute PetroChina Xinjiang Oilfield CompanyKaramayXinjiang834000China CNPC Xibu Drilling Engineering Company Limited UrumqiXinjiang830000China Engineering Technology Research Institute PetroChina Southwest Oil&Gas Field CompanyChengduSichuan610066China

The failure of cement sheath integrity can be easily caused by alternating pressure during large-scale multistage hydraulic fracturing in shale-gas *** elastic-plastic mechanical model of casing-cement sheath-formation(CSF)system under alternating pressure is established based on the Mohr-Coulomb criterion and thick-walled cylinder theory,and it has been solved by MATLAB programming combining global optimization algorithm with Global *** failure mechanism of cement sheath integrity is investigated,by which it can be seen that the formation of interface debonding is mainly related to the plastic strain accumulation,and there is a risk of interface debonding under alternating pressure,once the cement sheath enters plasticity whether in shallow or deep well *** matching relationship between the mechanical parameters(elastic modulus and Poisson's ratio)of cement sheath and its integrity failure under alternating pressure in whole well sections is studied,by which it has been found there is a“critical range”in the Poisson's ratio of cement *** the Poisson's ratio is below the“critical range”,there is a positive correlation between the yield internal pressure of cement sheath(SYP)and its elastic ***,when the Poisson's ratio is above the“critical range”,there is a negative *** elastic modulus of cement sheath is closely related to its Poisson's ratio,and restricts each *** and reasonable matching between mechanical parameters of cement sheath and CSF system under different working conditions can not only reduce the cost,but also protect the cement sheath integrity.

关键词： Casing-cement sheath-formation system Mechanical model Matching relationship Cement sheath integrity Critical range Mechanical parameters

Neurons-system-like structured SnS_(2)/CNTs composite for high-performance sodium-ion battery anode

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Rare Metals 2021年第6期40卷 1383-1390页

作者： Ling Zhu Xue-xian Yang Yan-Hong xiang peng Kong xian-Wen Wu School of Physics and Electromechanical Engineering Jishou UniversityJishou 416000China School of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China

Sodium-ion batteries(SIBs)have attracted significant attention with respect to renewable energy power generation systems because of the abundant reserves of sodium on ***,anode materials are presently limited by low energy density,poor rate performance and inferior cycling *** recent years,tin disulfide(SnS_(2))with a particular layered structure has been considered as a promising anode material for SIBs due to its high theoretical capacity and low ***,a nervoussystem-like structured SnS_(2)/CNTs composite was successfully synthesized via a hydrothermal *** SnS_(2)sheets were strung with carbon nanotubes(CNTs)to form a hierarchical porous structure,which is effective for electrolyte diffusion and electronic *** large distance of the(001)plane(0.5899 nm)of SnS_(2)favors Na+insertion-extraction *** from these structural characteristics,SnS_(2)/CNTs electrodes exhibit high specific capacity,excellent rate performance and superior cycling stability.A high charge capacity of 642 mAh·g^(-1)was released at 0.2 A·g^(-1),and then,a high reversible capacity of 427 mAh·g^(-1)was retained after 100 *** charged at 2 A·g^(-1),the SnS_(2)/CNTS electrode maintained a capacity of 282 mAh·g^(-1).The nervous-system-like structure of the SnS_(2)/CNTs composite provides a novel strategy for the development of SIBs with high electrochemical performance.

关键词： SnS_(2)/CNTs Sodium-ion batteries Anode Composite Rate capability

Multi-instance learning for software quality estimation in object-oriented systems:a case study

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第2期11卷 130-138页

作者： peng HUANG jie ZHU Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China

We investigate a problem of object-oriented (OO) software quality estimation from a multi-instance (MI) perspective. In detail,each set of classes that have an inheritance relation,named 'class hierarchy',is regarded as a bag,while each class in the set is regarded as an instance. The learning task in this study is to estimate the label of unseen bags,i.e.,the fault-proneness of untested class hierarchies. A fault-prone class hierarchy contains at least one fault-prone (negative) class,while a non-fault-prone (positive) one has no negative class. Based on the modification records (MRs) of the previous project releases and OO software metrics,the fault-proneness of an untested class hierarchy can be predicted. Several selected MI learning algorithms were evalu-ated on five datasets collected from an industrial software project. Among the MI learning algorithms investigated in the ex-periments,the kernel method using a dedicated MI-kernel was better than the others in accurately and correctly predicting the fault-proneness of the class hierarchies. In addition,when compared to a supervised support vector machine (SVM) algorithm,the MI-kernel method still had a competitive performance with much less cost.

关键词： Object-oriented (OO) software Multi-instance (MI) learning Software quality estimation Kernel methods

Simulation of non-Newtonian (Power-law) fluid flow past a row of square cylinders

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Science China(Physics,Mechanics & Astronomy) 2011年第4期54卷 703-710页

作者： ZHOU ZhiQiang peng jie Department of Engineering Mechanics Tsinghua University Beijing 100084 China

The power-law fluid flow past a row of uniform placed square cylinders is investigated using the Lattice Boltzmann method (LBM).The flow is assumed to be two-dimensional and *** relaxation time is assumed to be shear-dependent and determined by using a variable parameter related to the local shear *** effects of both shear-thinning/shear-thickening property and the cylinder spacing on the confluence of the jets are mainly *** bifurcation diagrams of the flow are obtained,which include confluences of double and quadruple *** results show that both the first and second pitchfork bifurcations are advanced due to the effect of the shear-thinning property,and postponed due to the shear-thickening property.

关键词： power-law fluid pitchfork bifurcation Lattice Boltzmann method

The Crystallization Behavior Regulating Nature of Hydrogen Bonds Interaction on Polyamide 6,6 by Poly(vinyl pyrrolidone)

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Chinese Journal of Polymer Science 2023年第3期41卷 394-404,I0008页

作者： Yang Liu Li peng jie-Long Lin Yong Zhou Du-Jin Wang Charles C.Han xian-Bo Huang Xia Dong National-certified Enterprise Technology Center Kingfa Science and Technology Co.LTD.Guangzhou 510663China CAS Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBejing 100190China University of Chinese Academy of Sciences Beijing 100049China

The crystallization behavior of polyamide 6,6(PA66) under complex flow field is of great importance for its final mechanical ***(vinyl pyrrolidone)(PVP) was applied as crystallization modifying agency to improve processability of *** regulation nature on hydrogen bonds(H-bonds) interaction of PVP was studied upon cooling *** revealed by in situ FTIR,the sample with 5 wt% PVP displays decreased enthalpy change(ΔH) for both the generation of H-bonds and the transition of H-bonds from “disordered” to “ordered” state,which illustrates the molecular mechanism for the regulation of crystallzation ***,2D-WAXD is applied to reveal the evolution of microstructure for sample under external injection *** orientation factor(f_(H)) decreases obviously with the addition of PVP,because the relaxation of chain segments is promoted as well the crystallization is *** above crystallization and microstructure changes during the processing provokes the improvement of processability without the apparent sacrifice of mechanical properties.

关键词： Polyamide 66 Poly(vinyl pyrrolidone) Hydrogen bonds interaction