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Factors Affecting Distribution of Vegetation Types on Abandoned Cropland in the Hilly-Gullied Loess Plateau Region of China

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Pedosphere 2008年第1期18卷 24-33页

作者： j.AO j.-Ying j. TZANOPOULOS P. XOFIS j. MITCHLEY Institute of Soil and Water Conservation Northwest Sci-Technology University of Agriculture and Forestry Yangling Shaanxi 712100 (China) Centre for Agro-Environmental Research Department of Agriculture The University of Reading Barley Gate PO Box237 Reading RG6 6.4 R (UK) Imperial College London Department of Agricultural Sciences Wye Campus Wye Ashford Kent TN25 5AH (UK) nstitute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling Shaanxi 712100 (China)

A study was conducted in the forest-steppe region of the Loess Plateau to provide insight into the factors affecting the process of vegetation establishment,and to provide recommendations for the selection of indigenous species in order to speed up the succession process and to allow the establishment of vegetation more resistant to soil *** distinctive vegetation types were identified,and their distribution was affected not only by the time since abandonment but also by other environmental factors,mainly soil water and total P in the upper soil *** of the vegetation types,dominated by Artemisia scoparia,formed the early successional stage after abandonment while the other three types formed later successional stages with their distribution determined by the soil water content and total *** can be concluded that the selection of appropriate species for introduction to accelerate succession should be determined by the local conditions and especially the total P concentration and soil water content.

关键词： abandoned cropland Loess Plateau soil erosion vegetation variation

A Bayesian Network Approach for Offshore Risk Analysis Through Linguistic Variables

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China Ocean Engineering 2007年第3期21卷 371-388页

作者： Ren j. Wang j. j.nkinson I. Xu D. L. Yang j. B. School of Engineering Liverpool John Moores University Liverpool L 3 3 AF UK Manchester Business School The University of Manchester Manchester M 60 1 QD UK

This paper presents a new approach for offshore risk analysis that is capable of dealing with linguistic probabilities in Bayesian networks （ BNs）. In this paper, linguistic probabilities are used to describe occurrence likelihood of hazardous events that may cause possible accidents in offshore operations. In order to use fuzzy information, an f-weighted valuation function is proposed to transform linguistic j.dgements into crisp probability distributions which can be easily put into a BN to model causal relationships among risk factors. The use of linguistic variables makes it easier for human experts to express their knowledge, and the transformation of linguistic j.dgements into crisp probabilities can significantly save the cost of computation, modifying and maintaining a BN model. The flexibility of the method allows for multiple forms of information to be used to quantify model relationships, including formally assessed expert opinion when quantitative data are lacking, or when only qualitative or vague statements can be made. The model is a modular representation of uncertain knowledge caused due to randomness, vagueness and ignorance. This makes the risk analysis of offshore engineering systems more functional and easier in many assessment contexts. Specifically, the proposed f-weighted valuation function takes into account not only the dominating values, but also the a-level values that are ignored by conventional valuation methods. A case study of the collision risk between a Floating Production, Storage and Off-loading （FPSO） unit and the anthorised vessels due to human elements during operation is used to illustrate the application of the proposed model.

关键词： Risk analysis fiweighted valuation function Bayesian networks fuzzy number linguistic probability off-shore engineering systems

The j.int Control of Variable Speed and On-Ramp Metering for Urban Expressway

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j.urnal of Systems Engineering and Electronics 2001年第3期12卷 25-30页

作者： Ma, j. Liu, X. Rong, j. Li, Z. Transportation Research Center Beijing Polytechnic University Beijing 100022 China

The traffic performance of urban expressway is subj.ct to non-recurring and recurring events, which may cause heavy congestion and vehicles long queuing on ramps. The low performance may bring more traffic delay to the whole network of urban road. This paper presents a new method, the j.int control of variable speed control and on-ramp metering, which attempts to improve the level of traffic operations on urban expressway. By analyzing traffic flow on urban expressway, an optimum control strategy of variable speed and on-ramp metering is established in the paper.

关键词： Function evaluation Highway traffic control Intelligent control Mathematical models Motor transportation Parameter estimation Ramp generators Speed control

Improved conservative level set method for free surface flow simulation

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j.urnal of Hydrodynamics 2014年第2期26卷 316-325页

作者：赵兰浩毛佳刘晓青 BAI Xin WILLIAMS j. j. R. College of Water Conservancy and Hydropower Engineering Hohai University School of Engineering and Materials Science Queen Mary University of London

By coupling the standard and the conservative level set methods, an improved conservative level set method is proposed to capture the free surface smoothly with excellent mass conservation properties. The improvement lies in the fact that the surface normal is computed from a signed distance function instead of the Heaviside function. Comparing with the conservative level set method, the inevitable numerical discretization errors to point the surface normal in arbitrary directions could be eliminated, and the instability of the numerical solution could be improved efficiently. The advantage is clear in the straightforward combination of the standard level set and the conservative level set and a little effort is taken in coding compared with other coupled methods. The present method is validated with several well-known benchmark problems, including the 2-D Zalesak＇s disk rotating, the 3-D sphere stretching in deformation vortex and the dam break flow simulation. The results are shown to be in good agreement with the published experimental data and numerical results.

关键词： flee surface flow improved conservative level set mass conservation

On the Bloch Constant for K-Quasiconformal Mappings in Several Complex Variables

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Acta Mathematica Sinica,English Series 2001年第2期17卷 237-242页

作者： j. Y. GAMALIEL Department of Mathematics. Nanj.ng Normal University. Nanj.ng 210097. P. R. China

We study the Bloch constant for K-quasiconformal holomorphic mappings of the unit ball B of Cn into Cn. The final result we prove in this paper is: If f is a K-quasiconformal holomorphic mapping of B into Cn such that det（f’（0））=1, then f（B） contains a schlicht ball of radius at least （CnK）1-n integral from n=0 to 1(（1+t）n-1/（1-t）2 exp{-（n+1）t/（1-t）}dt, where Cn>1 is a constant depending on n only, and Cn→101/2 as n→∞.

关键词： K-quasiconformal mapping Bloch constant

Context-dependency in medicine:how neuronal excitability influences the impact of dopamine on cognition

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Neural Regeneration Research 2025年第11期20卷 3225-3226页

作者： Mahboubeh Ahmadi Nahid Rouhi j.vad Mirnaj.fi-Zadeh Bechara j.Saab Department of Physiology Faculty of Medical SciencesTarbiat Modares UniversityTehranIran Mobio Interactive Pte.Ltd. SingaporeRepublic of Singapore

Dopamine,often termed the"feel-good"neurotransmitter,plays a crucial role in myriad physiological and psychological brain *** dopamine is primarily associated with pleasure,reward,and motivation,its effects can be quite complex;and this complexity is further compounded when examining how dopamine functions in typical versus disease-affected neural *** pa rticula r,epilepsy,characte rized by heightened brain excitability,is linked to cognitive dysfunction,and dopamine is implicated in elements of both its pathology and *** has been successful in describing the synaptic abnormalities believed to contribute to memory issues in epilepsy,aiding in the search for effective therapies for what persists as a maj.r medical issue.

关键词： dopamine epilepsy primarily

Brain-penetrating neurotrophic factor mimetics: HER-096 as a disease-modifying therapy for Parkinson’s disease

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Neural Regeneration Research 2025年第4期20卷 1094-1095页

作者： Natalia Kulesskaya Kira M.Holmström Henri j.Huttunen Herantis Pharma Plc EspooFinland

Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A maj.r unmet need in the field of central nervous system diseases is disease-modifying *** for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,*** that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.

关键词： diseases treatment therapeutic

Regulation of Power Conversion in Fuel Cells

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Chemical Research in Chinese Universities 2004年第4期20卷 466-469页

作者： ZHANG j. K. Scott School of Chemical Engineering & Advanced Materials University of Newcastle upon Tyne Newcastle upon TyneSchool of Chemical Engineering & Advanced Materials University of Newcastle upon Tyne Newcastle upon Tyne NE1 7RU UK NE1 7RU UK

Here we report a regulation about power conversion in fuel cells. This regulation is expressed as that total power produced by fuel cells is always proportional to the square of the potential difference between the \{equilibrium\} potential and work potential. With this regulation we deduced fuel cell performance equation which can describe the potential *** current performance curves, namely, polarization curves of fuel cells with three power source parameters: equilibrium potential E_0; internal resistance R; and power conversion coefficient K. The concept of the power conversion coefficient is a new criterion to evaluate and compare the characteristics and capacity of different fuel cells. The calculated values obtained with this equation agree with practical performance of different types of fuel cells.

关键词： Fuel cell Power conversion coefficient Internal resistance Performance Potential

Leader-following consensus control for networked multi-teleoperator systems with interval time-varying communication delays

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Chinese Physics B 2013年第7期22卷 96-103页

作者： M. j. Park S. M. Lee j. W. Son O. M. Kwon E. j. Cha School of Electrical Engineering Chungbuk National University School of Electronic Engineering Daegu University Division of IT-Convergence Daegu Gyeongbuk Institute of Science & Technology Department of Biomedical Engineering School of MedicineChungbuk National University

We study the leader-following consensus stability and stabilization of networked multi-teleoperator systems with interval time-varying communication delays. With the construction of a suitable Lyapunov–Krasovskii functional and the utilization of the reciprocally convex approach, novel delay-dependent consensus stability and stabilization conditions for the systems are established in terms of linear matrix inequalities, which can easily be solved by various effective optimization algorithms. One illustrative example is given to illustrate the effectiveness of the proposed methods.

关键词： multi-teleoperator systems interval time-varying delay leader–following consensus problem Lyapunov method