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Dynamic multimedia stream adaptation and rate control for heterogeneous networks

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j.urnal of Zhej.ang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 63-69页

作者： SZWABE Andrzej.SCHORR Andreas HAUCK Franz j. KASSLER Andreas j. Poznan University of Technology Poznan 60-965 Poland University of Ulm Ulm 89069 Germany University of Karlstad Karlstad SE-65188 Sweden

Dynamic adaptation of multimedia content is seen as an important feature of next generation networks and pervasive systems enabling terminals and applications to adapt to changes in e.g. context, access network, and available Quality-of-Service(QoS) due to mobility of users, devices or sessions. We present the architecture of a multimedia stream adaptation service which enables communication between terminals having heterogeneous hardware and software capabilities and served by heterogeneous networks. The service runs on special content adaptation nodes which can be placed at any location within the network. The flexible structure of our architecture allows using a variety of different adaptation engines. A generic transcoding engine is used to change the codec of streams. An MPEG-21 Digital Item Adaptation (DIA) based transformation engine allows adj.sting the data rate of scalable media streams. An intelligent decision-taking engine implements adaptive flow control which takes into account current network QoS parameters and congestion information. Measurements demonstrate the quality gains achieved through adaptive congestion control mechanisms under conditions typical for a heterogeneous network.

关键词： Stream adaptation, Quality-of-Service (QoS), Heterogeneous networks, Rate control, MPEG-21 DIA

Blood rheology and aging

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j.urnal of Geriatric Cardiology 2013年第3期10卷 291-301页

作者： Michael j. Simmonds Herbert j. Meiselman Oguz K. Baskurt Heart Foundation Research Centre Griffith Health Institute Griffith University Gold Coast QLD 4222 Australia Department of Physiology and Biophysics Keck School of Medicine University of Southern California Los Angeles CA 9033 USA Koc University School of Medicine Istanbul Turkey

The flow properties of blood play significant roles in tissue perfusion by contributing to hydrodynamic resistance in blood vessels. These properties are influenced by pathophysiological processes, thereby increasing the clinical relevance of blood rheology information. There is well-established clinical evidence for impaired blood fluidity in humans of advanced age, including enhanced plasma and whole blood viscosity, impaired red blood cell (RBC) deformability and enhanced RBC aggregation. Increased plasma fibrinogen concentration is a common finding in many studies owing to the pro-inflammatory condition of aged individuals;this finding of increased fibrinogen concen-tration explains the higher plasma viscosity and RBC aggregation in elderly subj.cts. Enhanced oxidant stress in advanced age is also known to contribute to altered blood fluidity, with RBC deformability being an important determinant of blood viscosity. Several studies have shown that physical activity may improve the hemorheological picture in elderly subj.cts, yet well-designed observational and mechanistic studies are required to determine the specific effects of regular exercise on hemorheological parameters in healthy and older individuals.

关键词： Aggregation Deformability Elderly Erythrocyte Red blood cell Viscosity

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

Outcomes after robot-assisted laparoscopic radical prostatectomy

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Asian j.urnal of Andrology 2009年第1期11卷 94-99页

作者： Declan G. Murphy Benj.min j. Challacombe Anthony j. Costello The Urology Centre Guy＇s ＆ St. Thomas ＇NHS Foundation Trust London SE1 9RT UK Department of Urology Royal Melbourne Hospital Melbourne VIC 3054 Australia

Robot-assisted laparoscopic radical prostatectomy （RALRP） using the da Vinci surgical system is now in widespread use in many countries where economic conditions allow the installation of this expensive technology. Controversy has surrounded the procedure since it was first performed in 2000, with many critics highlighting the lack of evidence to support its use. However, despite the lack of level I evidence, many large studies of patients have confirmed that the procedure is feasible and safe, with low morbidity. Available longer-term oncological data seem to show that outcomes from the robotic approach at least match those of traditional open radical prostatectomy. Functional outcomes also seem satisfactory, although randomized controlled trials are lacking. This paper reviews the current status of RALRP with respect to perioperative data and complications and oncologic and functional outcomes.

关键词： da Vinci laparoscopic outcomes prostate cancer radical prostatectomy robotic

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