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Non-probabilistic solutions of imprecisely defined fractional-order diffusion equations

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Chinese Physics B 2014年第12期23卷 14-20页

作者： s.Chakraverty smita Tapaswini Department of Mathematics National Institute of Technology RourkelaOdisha–769 008 India

The fractional diffusion equation is one of the most important partial differential equations（PDEs） to model problems in mathematical physics. These PDEs are more practical when those are combined with uncertainties. Accordingly, this paper investigates the numerical solution of a non-probabilistic viz. fuzzy fractional-order diffusion equation subjected to various external forces. A fuzzy diffusion equation having fractional order 0 〈 α≤ 1 with fuzzy initial condition is taken into consideration. Fuzziness appearing in the initial conditions is modelled through convex normalized triangular and Gaussian fuzzy numbers. A new computational technique is proposed based on double parametric form of fuzzy numbers to handle the fuzzy fractional diffusion equation. Using the single parametric form of fuzzy numbers, the original fuzzy diffusion equation is converted first into an interval-based fuzzy differential equation. Next, this equation is transformed into crisp form by using the proposed double parametric form of fuzzy numbers. Finally, the same is solved by Adomian decomposition method（ADM） symbolically to obtain the uncertain bounds of the solution. Computed results are depicted in terms of plots. Results obtained by the proposed method are compared with the existing results in special cases.

关键词： double parametric form of fuzzy number fuzzy fractional diffusion equation ADM

Approaches to antiretroviral therapy in China

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Cell Research 2005年第Z1期15卷 895-902页

作者： Bruce l GIllIAM Robert R REDFIElD Division of Clinical Care and Research Institute of Human Virology University of Maryland Baltimore MD 21201 USA

China has recognized the threat of HIV to its population and responded with a national antiretroviral treatment (ART) program. However, high ART failure rates and the spread of resistance within populations are important realities to consider when developing and managing ART programs in China and worldwide. Concepts which will define treatment success and local and national programmatic goals are 1) access to ART, 2) durability of ART at the patient level, 3) scalability of treatment modalities, and the 4) sustainability of the program at the community or national level. In the face of limited resources, China must also consider when to start ARV therapy, which agents to use, when to switch them, and how to treat highly experienced patients with drug resistance. The optimal ARV regimen to start with is changing frequently with the introduction of new agents and the presentation of new data. Currently, a regimen including tenofovir, emtricitabine or lamivudine and a nonnucleoside reverse transcriptase inhibitor appears to have optimal characteristics to treat HIV/AIDs in China. However, critical to all of these choices is the evaluation of programs implemented to insure wide scale success. China has wisely begun this process of evaluating the perfor- mance of local programs through systematic monitoring and evaluation of treatment outcomes. This will allow regi- mens and programs that work to be expanded, and programs with high failure rates to be eliminated. In the end, evidence based data supporting treatment strategies will allow China to successfully confront its AIDs epidemic early and prevent its tragic consequences

关键词： antiretroviral therapy scalability HIV/AIDs.

Necessity and adequacy of near-source factors for not-so-tall fixed-base buildings

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Earthquake Engineering and Engineering Vibration 2015年第1期14卷 13-26页

作者： Cenk Alhan Melih sürmeli Department of Civil Engineering Istanbul University Avc?lar Campus Department of Civil Engineering Istanbul Kültür University Atak?y Campus

Nonlinear response history analyses and use of strong ground motion data including near-field effects has become a common practice in both performance based design of tall buildings and design of base-isolated buildings. On the other hand, ordinary buildings are commonly analysed via response spectrum analysis following the rules of conventional seismic codes, most of which do not take near-field effects into account. This study evaluates the necessity and the adequacy of near-source factors for ordinary fixed-base buildings that are not specifically classified as tall, by comparing dynamic responses of 3, 8, and 15-story benchmark buildings obtained via （1） linear time history analyses using 220 record components from 13 historical earthquakes and 45 synthetic earthquake records of different magnitudes and fault distances and （2） response spectrum analyses in accordance with the Turkish Earthquake Code 2007 -representing seismic codes not taking near-field effects into account- and the Uniform Building Code 1997 which takes near-field effects into account via near-source factors that amplify design response spectrum. It is shown that near-source factors are crucial for the safe design of not-so-tall ordinary fixed-base buildings but those defined in UBC97 may still not be adequate for those located in the vicinity of the fault.

关键词： near-field effects near-source factors low-rise buildings mid-rise buildings

Neumann＇s method for boundary problems of thin elastic shells

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Applied Mathematics and Mechanics(English Edition) 2017年第4期38卷 543-556页

作者： Y. s. NEUsTADT Department of Civil Engineering Samara State Architectural and Building University Samara 443001 Russia

The possibility of using Neumann＇s method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the distribution space. The convergence of Neumann＇s method is proven for the shells with holes when the boundary of the domain is not completely fixed. The numerical implementation of Neumann＇s method normally requires significant time before any reliable results can be achieved. This paper suggests a way to improve the convergence of the process, and allows for parallel computing and evaluation during the calculations.

关键词： boundary problem thin elastic shell theory Neumann's method variational principle Korn's inequality distribution embedding theorem Green tensor

Male mate choice as differential investment in contest competition is affected by female ornament expression

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Current Zoology 2018年第3期64卷 335-344页

作者： stacey l. WEIss Matthew DUBIN Department of Biology University of Puget Sound 1500 N. Warner Street No. 1088 Tacoma WA 98418-1088 USA

High male mating effort and high variation in female quality select for male mate choice, which may be expressed as differential investment of reproductive effort based on female value. Male reproductive effort includes investment in direct contest competition with rival males for access to females, yet variation in male-male contest behavior is rarely examined in the context of male mate choice. We examine such male response to variation in female body size, reproductive state, and female-specific ornamentation in the striped plateau lizard, sceloporus virgatus. We housed lizards in trios of 2 size-matched males and one female for 5 days, such that all 3 lizards were physi- cally isolated and the males could see the female but not each other. We then placed males simultaneously into the female＇s cage and scored the interaction. Male-male aggression was not significantly affected by female body size, reproductive state, nor ornament color, but was influenced by ornament size which reliably signals the phenotypic quality of the female and her off- spring. In the presence of larger-ornamented females, males engaged in more male-male aggressive display behavior more quickly, and performed fewer high-intensity contact behaviors but were equally likely to escalate to this riskier level of fighting. Our data suggest that males adjust their energetic investment during intrasexual competitive interactions in response to variation in the contested female which, assuming males gain direct or indirect benefits from their strategic allocation of reproductive effort, fits the modern understanding of male mate choice.

关键词： aggression female-specific ornaments intrasexual competition lizards resource quality sexual selection

Beyond dichotomies in species and speciation

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National science Review 2022年第12期9卷 15-17页

作者： Jeffrey l.Feder Patrik Nosil Department of Biological sciences University of Notre Dame Centre d'Ecologie Fonctionnelle et Evolutive University MontpellierCNRS EPHE IRD

speciation is not as mysterious as D arwin once described it [1].Nevertheless,important questions *** discussed by Wu[2] and highlighted in a series of papers in National science Review (NsR),these issues equate with imposing dichotomous perspectives on speciation,when the nature of species and the processes creating them can complicate discrete categorization.

关键词： DIVERGENCE EVOlUTION ADAPTATION INVERsIONs CONTINUUM RACE

Assessing the reproductive health of men with occupational exposures

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Asian Journal of Andrology 2014年第1期16卷 23-30页

作者： steven M schrader Katherine l Marlow Centers for Disease Control and Prevention National Institute for Occupational Safety and Health Division of Applied Research and Technology Cincinnati OH USA.

The earliest report linking environmental （occupational） exposure to adverse human male reproductive effects dates back to1775 when an English physician, Percival Pott, reported a high incidence of scrotal cancer in chimney sweeps. This observation led to safety regulations in the form of bathing requirements for these workers. The fact that male-mediated reproductive harm in humans may be a result of toxicant exposures did not become firmly established until relatively recently, when lancranjan studied lead-exposed workers in Romania in 1975, and later in 1977, when Whorton examined the effects of dibromochloropropane （DBCP） on male workers in California. since these discoveries, several additional human reproductive toxicants have been identified through the convergence of laboratory and observational findings. Many research gaps remain, as the pool of potential human exposures with undetermined effects on male reproduction is vast. This review provides an overview of methods used to study the effects of exposures on male reproduction and their reproductive health, with a primary emphasis on the implementation and interpretation of human studies. Emphasis will be on occupational exposures, although much of the information is also useful in assessing environmental studies, occupational exposures are usually much higher and better defined.

关键词： accessory glands endocrine epidemiology semen sexual function sperm testis toxicology

X-ray scattering from liquid interfaces

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Nuclear science and Techniques 2006年第6期17卷 322-333页

作者： lI Ming Mark l. sCHlOssMAN Beijing National laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China Departments of Physics and Chemistry University of Illinois at Chicago 845 W. Taylor St Chicago IL 60607 USA

synchrotron radiation X-ray scattering is a useful tool for structural characterization of liquid interfaces. specular reflectivity provides precise measurement of the interfacial widths and of the ordering of surfactants adsorbed to these interfaces. Diffuse scattering gives information on phase transitions and domain formation in surfactant monolayers and on interfacial fluctuations confined by and coupled across fluidic films.

关键词： X-射线散射液体界面同步加速器反射率

Comparison of Reynolds Averaged Navier-stokes Based simulation and large-eddy simulation for One Isothermal swirling Flow

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Journal of Thermal science 2012年第2期21卷 154-161页

作者： sφren Knudsen Kr Department of Energy Technology Pontoppidanstrde 101 9220 Aalborg Denmark

The flow structure of one isothermal swirling case in the sydney swirl flame database was studied using two numerical methods. Results from the Reynolds-averaged Navier-stokes (RANs) approach and large eddy simulation (lEs) were compared with experimental measurements. The simulations were applied in two different Cartesian grids which were investigated by a grid independence study for RANs and a post-estimator for lEs. The RNG k-ε turbulence model was used in RANs and dynamic smagorinsky-lilly model was used as the sub-grid scale model in lEs. A validation study and cross comparison of ensemble average and root mean square (RMs) results showed lEs outperforms RANs statistic results. Flow field results indicated that both approaches could capture dominant flow structures, like vortex breakdown (VB), and precessing vortex core (PVC). streamlines indicate that the formation mechanisms of VB deducted from the two methods were different. The vorticity field was also studied using a velocity gradient based method. This research gained in-depth understanding of isothermal swirling flow.

关键词： large eddy simulation vortex breakdown vorticity field coherent structure