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A novel method of constructing high-dimensional digital chaotic systems on finite-state automata

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Chinese Physics B 2020年第9期29卷 233-243页

作者： Jun Zheng Han-ping hu School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Image Information Processing and Intelligent Control Ministry of EducationWuhan 430074China

When chaotic systems are implemented on finite precision machines, it will lead to the problem of dynamical degradation. Aiming at this problem, most previous related works have been proposed to improve the dynamical degradation of low-dimensional chaotic maps. This paper presents a novel method to construct high-dimensional digital chaotic systems in the domain of finite computing precision. The model is proposed by coupling a high-dimensional digital system with a continuous chaotic system. A rigorous proof is given that the controlled digital system is chaotic in the sense of Devaney's definition of chaos. Numerical experimental results for different high-dimensional digital systems indicate that the proposed method can overcome the degradation problem and construct high-dimensional digital chaos with complicated dynamical properties. Based on the construction method, a kind of pseudorandom number generator (PRNG) is also proposed as an application.

关键词： high-dimensional digital chaotic system dynamical degradation anti-control pseudorandom number generator

Biomass Components and Environmental Controls in Ningxia Grasslands

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Journal of Integrative Agriculture 2012年第12期11卷 2079-2087页

作者： WANG Kai-bo LI jian-ping SHANGGUAN Zhou-ping State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences School of Agriculture Ningxia University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences

Grassland plays an important role in the global carbon cycle and climate regulation. However, there are still large uncertainties in grassland carbon pool and also its role in global carbon cycle due to the lack of measured grassland biomass at regional scale or global scale with a unified survey method, particular for below-ground biomass. The present study, based on a total of 44 grassland sampling plots with 220 quadrats across Ningxia, investigated the characteristics of above-ground biomass （AGB）, below-ground biomass （BGB）, litter biomass （LB）, total biomass （TB） and root：shoot ratios （R：S） for six predominantly grassland types, and their relationships with climatic factors. AGB, BGB, LB and TB varied markedly across different grassland types, the median value ranging from 28.2-692.6 g m-2 for AGB, 130.4-2 036.6 g m-： for BGB, 9.2-82.3 g m2 for LB, and 168.0-2 681.3 g m-： for TB. R：S showed less variation with median values from 3.2 to 5.3 （excluding marshy meadow）. The different grassland types showed similar patterns of biomass allocation, with more than 70% BGB for all types. There is evidence of strong positive effects associated with mean annual precipitation （MAP） and negative effects associated with mean annual temperature （MAT） on AGB, BGB, and LB, although both factors have the opposite effect on R：S.

关键词： grasslands above-ground biomass (AGB) below-ground biomass (BGB) root:shoot ratios (R:S) mean annual precipitation (MAP) mean annual temperature (MAT)

Research on the fracture behavior of PBX under static tension

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Defence Technology（防务技术） 2014年第2期10卷 154-160页

作者： hu GUO Jing-run LUO ping-an SHI jian-guo XU Institute of Systems Engineering China Academy of Engineering Physics

The fracture behavior of polymer-bonded explosive(PBX) seriously affects the safety and reliability of weapon *** effects of interface debonding and initial meso-damage on the fracture behavior of PBX under quasi-static tension are studied using numerical method.A twodimensional representative volume element(RVE) is established based on Voronoi model in which the component contents could be regulated and the particles are randomly distributed.A nonlinear damage model of polymer matrix relative to matrix depth between particles is *** results show that the simulated strain-stress relation is coincident with experiment *** is found that interface debonding leads to the nucleation and propagation of meso-cracks,and a main crack approximately perpendicular to the loading direction is generated *** interface debonding tends to occur in the interface perpendicular to the loading *** seems to be a phenomenon that strain softening and hardening alternatively appear around peak stress of stress and strain *** is shown that the initial damages of intragranular and interfacial cracks both decrease the modulus and failure stress,and the main crack tends to propagate toward the initial meso-cracks.

关键词：拉伸断裂行为 PBX 准静态界面裂纹损伤模型峰值应力裂纹传播武器系统

Formation Mechanism and Binding Energy for Equilateral Triangle Structure of He3+ Cluster

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Communications in Theoretical Physics 2002年第5期38卷 597-600页

作者： GOU Qing-Quan ZHANG jian-ping LI ping Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China Department of Physics Leshan Teacher's College Leshan 614000 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The formation mechanism for the equilateral triangle structure of the He3+ cluster is proposed. The curveof the total energy versus the internuclear distance R for this structure has been calculated by the method of a modifiedarrangement channel quantum mechanics. The result shows that the curve has a minimal -7.81373 a.u at 1 = 1.55 *** binding energy of He3+ with respect to He+He+ +He was calculated to be 0.1064 a.u. (about 2.89 eV). This meansthat the He3+ cluster may be formed in the equilateral triangle structure stably by the interaction of He+ with two heliumatoms.

关键词： He3+ cluster, binding energy, equilateral triangle structure

The neuroscience of pain,addiction,and anesthesia

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Zoological Research 2024年第3期45卷 709-710页

作者： Ji hu ping Zheng School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Medical Neurobiology Institutes of Brain ScienceMOE Frontier Center for Brain ScienceDepartment of Neurology of Zhongshan HospitalFudan UniversityShanghai 200032China

Researchers and clinicians have long been interested in the mechanisms of pain,anesthesia,and *** International Association for the Study of Pain(IASP)defines pain as an unpleasant sensory and emotional experience associated with,or resembling that associated with,actual or potential tissue damage(Raja et al.,2020).Drug addiction refers to a condition of reliance that develops from regular drug consumption,which may lead to withdrawal symptoms when use is *** involves the complete loss of consciousness induced by an inhaled or intravenous anesthetic(Tosello et al.,2022).In this special collection,Zoological Research presents research findings focused on pain,addiction,and anesthesia.

关键词： anesthesia damage

Enhanced Mechanical Properties of Poly(arylene sulfide sulfone)Membrane by Co-electrospinning with Poly(m-xylene adipamide)

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Chinese Journal of Polymer Science 2020年第1期38卷 63-71,I0007页

作者： Lu Chen Xin-Lin Tuo Xi-Chuan Fan Chun-Jie Xie Bao-hua Guo jian Yu ping hu Zhao-Xia Guo Key Laboratory of Advanced Materials (Ministry of Education) Department of Chemical Engineering Tsinghua University

The mechanical properties of poly(arylene sulfide sulfone)(PASS) electrospun membrane were significantly enhanced by coelectrospinning with semi-aromatic nylon poly(m-xylene adipamide)(MXD6), another engineering plastic with high thermal stability and good mechanical properties. The tensile strength of PASS membrane increased with increased incorporation of MXD6, and was tripled when 20%MXD6 was incorporated. The mechanism of the mechanical property improvement is the existence of hydrogen bonding interaction between PASS and MXD6 and between adjacent fibers at the intersections. Thermal properties of the PASS/MXD6 membranes were evaluated by differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA), which showed that the membranes could be stably utilized up to180 °C without any change in appearance and without decomposition. Contact angle measurements of all the membranes showed hydrophobic character. To demonstrate the potential applications of PASS/MXD6 blend membranes, their oil absorption capacities were evaluated with three oils of different viscosities, which proved that the PASS/MXD6 membranes are better absorbents than commercial non-woven polypropylene fibers. Therefore, PASS/MXD6 fibrous membranes produced by electrospinning have a great potential in practical applications.

关键词： Electrospinning Mechanical properties PASS MXD6 Oil absorption

An Efficient Method for the Synthesis of Acyl-diazenes Using NaNO_2/NaHSO_4·H_2O

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Chinese Chemical Letters 2003年第7期14卷 677-680页

作者： jian ping LI ping LIU Yu Lu WANG College of Chemistry&Environmental Science Henan Normal UniversityXinxiang 453002 Key Laboratory of Environmental Science and Technology of High Education of Henan Province Xinxiang 453002

An efficient and convenient method for the synthesis of acyl-diazenes is reported. Ten acyl-diazenes have been synthesized from acylhydrazines in excellent yields under mild conditions. There are eight new substances... 详细信息

关键词： Acyl-diazenes acylhydrazines NaNO2/NaHSO4H2O.

VARIATION IN FLOW AND SEDIMENT OF DASHA RIVER AND INFLUENCE OF huMAN ACTIVITIES ON IT IN SOUTHWEST REGION OF ANhuI PROVINCE

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Chinese Geographical Science 2006年第2期16卷 109-115页

作者： CHEN Bao-ping ZHANG jian-chun State Key Laboratory of Estuarine and Coastal Research East China Normal Un＆ersity Shanghai 200062 P. R. China Department of Geography Chizhou Teachers College of A nhui Province Chizhou 247000 P. R. China School of humanities Hangzhou Teachers College Hangzhou 310036 P. R. China

Soil and water loss is now a major environmental problem in many areas of China, especially in the area of the Dabie Mountain, Anhui Province, which results in environmental degradation and does harm to the people＇s life and production there. Based on the observational records from the Dasha River, the authors analyze the character of the variation in flow and sediment in different flood and dry seasons from 1970 to 2000. The result shows that human activities had significantly reduced the sediment discharge and sediment module, and increased the runoff in low-water seasons since the 1980s. The average contribution rate ofhnman activities to decreasing sediment was 65.67%, and at the same period the contribution rate of runoff and rainfall was about 34.33%. Therefore, it is necessary to take the biological and engineering measures to solve the problem of soil and water loss in the Dasha River watershed.

关键词： river flow sediment discharge human activities effect Dasha River southwest of Anhui Province

NUMERICAL SIMULATION FOR THE SIMPLE SHEAR TEST IN AMORPHOUS GLASSY POLYMERS

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Acta Mechanica Solida Sinica 1999年第1期12卷 36-42页

作者： hu ping Wang Demin Jilin Univ Technol Inst Automobile Panel Forming Technol Changchun 130025 Peoples R China Jilin Univ Technol Dept Appl Mech Changchun 130025 Peoples R China

In this paper , a driving stress finite element method ofelastic-plastic large deformation based on implicit time integratingalgorithm and an eight-chain molecular network model is used for thenumerical simulation of the simple shear test ofpolycarbonate(PC)materials. The simulated results are compared withexperimental ones. The strain localiztaion propagation for the shearband deforma- tion for simple shear deformation is investigatednumerically. The effects of microstructure parameters in the model onstrain softening and orientation hardening of the PC are discussed indetail.

关键词： driving stress finite element method eight-chain molecular network model polycarbonate