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Does foraging mode affect metabolic responses to feeding？ A study of pygopodid lizards

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current Zoology 2013年第5期59卷 618-625页

作者： Michael WALL Michael b. THOMPSOn Richard SHInE School of biological Sciences A08 University of Sydney NSW 2006 Australia current address: 4940 Anza St. #4 San Francisco CA 94121 USA

Foraging mode （ambush vs. active） profoundly affects many aspects of organismal biology, including metabolic rates and their relationship with food intake. Previous studies on snakes suggest that ambushers tend to have lower standard metabolic rates （SMR） and higher energetic costs of digestion and assimilation of prey （specific dynamic action, or SDA） than do active foragers. However, phylogenetic considerations may be at least partly responsible for such patterns, as foraging mode is strongly conserved evolutionarily and most SDA studies have focused on species from only two lineages of ambush foragers （pythonid and viperid snakes） and one lineage of active foragers （colubrid snakes）. We sought to deconfound the effects of phylogeny and foraging mode, investigating SMR and SDA in two closely related pygopodid lizards, the common scaly-foot Pygopus lepidopo- dus （active forager） and burton＇s legless lizard Lialis burtonis （ambush forager）. consistent with the pattern seen in snakes, L. burtonis exhibits a significantly lower SMR and a higher SDA than does P lepidopodus. The magnitude of SDA in L. burtonis is comparable to that of some pythons and vipers, providing yet more evidence for the remarkable convergence between this species and ambush-foraging snakes [current Zoology 59 （5）： 618-625, 2013].

关键词： Ecology Metabolic rates Reptile Specific dynamic action

Investigation of the Influence of Free convection on the Heat Transfer of cylinders with Different Aspect Ratios

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Journal of Thermal Science 2001年第1期10卷 58-63页

作者： c.Henselowsky H.c.Kuhlmann 等 ZARMUniversityofbremen AmFallturmD－28359BremenGermany ZARMUniversityofbremen AmFallturmD－28359Brem

The heat transfer from an electrically heated cylinder (wire) of finite length to the surrounding fluid can be divided into heat radiation, conduction and convection. A technical application of these cylinders with typical dimensions of 1-2 mm length and a few micrometers diameter is the *** systematic study should clarify the influence of the convection to three dimensional heat transfer of cylinders. For this aim it is planned to investigate Reynolds numbers below Re = 1 (creeping flow). For this reason measurements should be done under 1g in the earth laboratory and also under microgravity (μg) conditions. comparisons of these measurements under otherwise same conditions allows to distinguish between the pure convection heat transfer and the contributions due to conduction and other effects. For measarements under μg the Drop Tower bremen can be used as research facility. Due to the fast response of convection to changes in the gravity conditions the Drop Tower is an ideal and cost efficient experimental tool. The experimental setup is build to operate at velocity range of 0-l m/s which includes the whole range of convection from pure free convection at 0 m/s over mixed convection up to pure forced convection at velocities above about 0.15 m/s. This velocity region corresponds to a range of the Reynolds number of Re = 0 - 0.18 for a cylinder of 5 μ m diameter at Tf= 140℃ in air at an ambient temperature of about 21℃.

关键词： thermal anemometry hot-wire microgravity free convection hat transfer.

An improved optimal elemental method for updating finite element models

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Earthquake Engineering and Engineering Vibration 2004年第1期3卷 67-74页

作者：段忠东 Spencer b.F. 闫桂荣欧进萍 School of civil Engineering Harbin Institute of Technology Department of civil and Environmental Engineering University of Illinois at Urbana-Champaign

The optimal matrix method and optimal elemental method used to update finite element models may not provide accurate *** situation occurs when the test modal model is incomplete,as is often the case in *** improved optimal elemental method is presented that defines a new objective function,and as a byproduct,circumvents the need for mass normalized modal shapes,which are also not readily available in *** solve the group of nonlinear equations created by the improved optimal method,the Lagrange multiplier method and Matlab function fmincon are *** deal with actual complex structures, the float-encoding genetic algorithm(FGA)is introduced to enhance the capability of the improved *** examples,a 7- degree of freedom(DOF)mass-spring system and a 53-DOF planar frame,respectively,are updated using the improved method. The example results demonstrate the advantages of the improved method over existing optimal methods,and show that the genetic algorithm is an effective way to update the models used for actual complex structures.

关键词： model updating optimal elemental method Lagrangc multiplier method genetic algorithm

Localized States of an Excess Electron in an Ionic cluster

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communications in Theoretical Physics 2013年第12期60卷 738-746页

作者： K.V.Grigorishin b.I.Lev boholyubov Institute for Theoretical Physics of the national Academy of Sciences of Ukraine

A theory of an electron affinity for an ionic cluster is proposed both in a quasiclassical approach and with quantization of a polarization electric field in a nanopartiele. A critical size of the cluster regarding in formation of an electron＇s autolocalized state, dependencies of energy and radius of a polaron on a cluster＇s size are obtained by a variational method. It has been found that binding energy of the electron in the cluster depends on a eluster＇s radius but a radius of electron＇s auto-localization does not depend on the cluster＇s radius and it equals to the polaron radius in a corresponding infinity crystal. A bound state of the electron in a cluster is possible only if the duster＇s radius is more than the polaron radius.

关键词： cluster polaron autolocalization phonon comfinement

A four parameter cubic equation of state with temperature dependent covolume parameter

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chinese Journal of chemical Engineering 2019年第5期27卷 1132-1148页

作者： Pradnya n.P.Ghoderao Vishwanath H. Dalvi Mohan narayan Department of Physics Institute of Chemical TechnologyMumbai 400019India Department of chemical Engineering Institute of Chemical TechnologyMumbai 400019India

A four-parameter, Ghoderao–Dalvi–narayan 2 cubic equation of state(GDn2 cEOS), is presented which incorporates the following: 1. The experimental value of the critical compressibility factor has been used as a fixed input parameter for calculations;2. All the parameters(a, b, c, d) of cEOS are temperature dependent functions in the subcritical region and are temperature independent functions in the supercritical region and;3. A new α function is introduced with two compound specific parameters which are estimated by matching saturated vapor pressure at two fixed temperature points Tr= 0.5, 0.7. Our formalism enables us to cast three of the four parameters of the cEOS as a function of the remaining parameter. The proposed cEOS is used to predict properties of 334 pure compounds, including saturated vapor pressure and liquid density, compressed liquid density, heat capacities at the constant pressure and volume, enthalpy of vaporization, sound velocity. To calculate thermodynamic properties of a pure compound, the present cEOS require the critical temperature, the critical pressure, the Pitzer’s acentric factor, the critical compressibility factor, and two parameters of the alpha function. The saturated liquid density predictions for pure fluids are very accurate when compared with GDn1(Ghoderao–Dalvi–narayan 1),MPR(Modified Peng–Robinson), and PT(Patel–Teja) equations of state. Unlike MPR EOS, the proposed temperature dependent covolume parameter b in the present work satisfies all the constraints mentioned in the literature to avoid thermodynamic inconsistencies at the extreme temperature and pressure. Using van der Waals one-fluid mixing rule, the present cEOS is further used to predict bubble pressure and the vapor mole fraction of binary mixtures.

关键词： Phase equilibria Thermodynamic properties Vapor-liquid equilibria The cubic equation of state covolume parameter Supercritical region

classical Electromagnetic Field Theory in the Presence of Magnetic Sources

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chinese Physics Letters 2003年第3期20卷 321-324页

作者： Li Kang chen Wen-Jun carlos M. naón Department of Physics Hangzhou Teacher's College Hangzhou 310036 Department of Physics Zhejiang University Hangzhou 310027 Instituto de Física La Plata Departamento de Física Facultad de Ciencias Exactas Universidad Nacional de La Plata CC 67 1900 La Plata Argentina

Using two new well-defined four-dimensional potential vectors, we formulate the classical Maxwell field theory in a form which has manifest Lorentz covariance and SO(2) duality symmetry in the presence of magnetic sources. We set up a consistent Lagrangian for the theory. Then from the action principle we obtain both Maxwell's equation and the equation of motion of a dyon moving in the electromagnetic field.

关键词： Maxwell equations

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小剂量化疗对骨髓增生异常综合征的作用

国外医学（输血及血液学分册） 1993年第5期16卷 299-300页

作者： Aul c Gattermann n 杨清宇

小剂量化疗的基本原理用小剂量化疗医治骨髓增生异常综合征(MDS),主要根据两种考虑:第一,MDS患者年龄较大,不能很好耐受强烈诱导化疗,大约50%MDS病人用强烈治疗诱导失败的原因是由于骨髓增生抑制引起的感染或出血。但是大家认为,若减少... 详细信息

小剂量化疗的基本原理用小剂量化疗医治骨髓增生异常综合征(MDS),主要根据两种考虑:第一,MDS患者年龄较大,不能很好耐受强烈诱导化疗,大约50%MDS病人用强烈治疗诱导失败的原因是由于骨髓增生抑制引起的感染或出血。但是大家认为,若减少细胞毒药物的剂量即可增进其实用价值,它可以停止或至少延迟MDS的进展。其次,用小剂量化疗医治MDS系依据在体外某些药物如Ara-c、阿克拉霉素、5-氮杂胞苷(5-azacytidine)、6-硫鸟嘌呤等,具有促进髓系白血病细胞分化成熟的能力。

关键词：药物疗法骨髓增生异常

Measurement and engineering application of adsorbed water content in fine-grained soils

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Journal of central South University 2021年第5期28卷 1555-1569页

作者： ZHAnG Rui XIAO Yu-peng WU Meng-li ZHEnG Jian-long MILKOS b c national Engineering Laboratory of Highway Maintenance Technology Changsha University of Science&TechnologyChangsha 410114China School of Traffic and Transportation Engineering Changsha University of Science&TechnologyChangsha 410114China

In this paper,the content and density of adsorbed water in fine-grained soil are *** to the test results,the calculation method of compaction degree of the solid-phase and void ration of soil is *** kinds of fine-grained soils from different regions in china were selected,and the adsorbed water content and density of four kinds of fine-grained soils were determined by thermogravimetry and volumetric flask ***,SEM and XRD experiments were used to analyze the differences in the ability of each soil sample to absorb *** order to study the compression characteristics of adsorbed water,four saturated soil samples were tested by consolidation *** results show that the desorption temperature range of the adsorbed water and its density were equal to 100−115℃and 1.30 g/cm^(3),*** water plays a positive role in keeping the compressibility of fine-grained soil at a low rate when it has high water ***,adsorbed water can be a stable parameter and is difficult to discharge during the operation period of *** settlement of fine-grained soil embankment is predicted by engineering example,and compared with the result of conventional calculation *** results show that it is more close to the field monitoring results by using the improved void ratio of soil as the parameter.

关键词： adsorbed water volumetric flask method thermogravimetric analysis method void ratio settlement

Enhanced Trust based Access control for Multi-cloud Environment

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computers, Materials & continua 2021年第12期69卷 3079-3093页

作者： n.R.Rejin Paul D.Paul Raj Technology PuduvoyalGummidipoondi601206India R M D Engineering college KavaraipettaiGummidipoondi601206India

Security is an essential part of the cloud *** ensuring the security of the data being communicated to and from the cloud server,a significant parameter called trust was ***-based security played a vital role in ensuring that the communication between cloud users and service providers remained unadulterated and *** most cloud-based data distribution environments,emphasis is placed on accepting trusted client users’requests,but the cloud servers’integrity is seldom *** paper designs a trust-based access control model based on user and server characteristics in a multi-cloud environment to address this *** proposed methodology consists of data encryption using cyclic Shift Transposition Algorithm and trust-based access control *** this trust-based access control mechanism framework,trust values are assigned to cloud users using direct trust *** direct trust degree is estimated based on the following metrics:success and failure rate of interactions,service satisfaction index,and dishonesty *** addition to this,trust values are assigned to cloud servers based on the metrics:server load,service rejection rate,and service access *** role-based Access control policy of each user is modified based on his trust *** the server fails to meet the minimum trust level,then another suitable server will be *** proposed system is found to outperform other existing systems in a multi-cloud environment.

关键词： cloud computing trust access control cloud service provider cloud data user cSTA