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Fine sediment carrying capacity of combined w.ve and current flow.

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International Journal of Sediment Research 2009年第4期24卷 425-438页

作者： Onyx w. h. w.I Department of Civil & Structural Engineering The Hong Kong Polytechnic University

Th. so-called fine sediment in many coastal areas and estuaries in Ch.na is mostly referred to th. mixture of coh.sive sediment and non-coh.sive sediment. To predict th. mixed type fine sediment transport, sediment carrying capacity formulae combined w.th.th. 2-D suspended sediment transport equation and morph.logic equation h.ve been w.dely used in Ch.na. In th. present study, th. sediment carrying capacity formula suggested by Dou et al. (1995) for w.ve conditions h.s been improved and implemented for th. prediction of sediment transport in nearsh.re regions w.0}re w.ve activities are significant. Th. improvement is based on th. w.ve energy dissipation principle inside and outside th. surf zone. In th. improved formula, sediment in suspension increases w.th.th. magnitude of th. w.ve period and th.s feature complies w.th.general observations. More th.n 300 laboratory and field measured data sets h.ve been review.d and 12 of th.m h.ve been used to verify and determine th. major coefficients in th. improved formula. Th. application of th. sediment carrying capacity model in combined w.ve and current situations sh.w. th.t th. model can faith.ully reproduce th. cross-sh.re sediment concentration distributions at th. south.est coast of Boh.i Bay.

关键词： Sediment carrying capacity Combined w.ve and current Sediment transport Fine sediment Boh.i Bay Surf zone

Ch.mical cues from kingsnakes do not cause inducible defenses in h.use mice

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Current Zoology 2012年第6期58卷 797-804页

作者： w. w.llace STARKE Ⅲ Mich.el h. FERKIN Department of Biological Sciences Ellington Hall University of Memphis Memphis TN 38152 USA

Abstract Many rodents exh.bit inducible defenses w.0}n exposed to ch.mical cues from mammalian predators. Th.se responses may include delays in sexual maturation, smaller adult body size and decreases in litter size and pup w.igh.. w. exposed th. h.brid juvenile offspring of field-caugh. and lab-descended h.use mice Mus musculus to th. ch.mical cues of mouse-fed or ch.ck-fed kingsnakes, Lampropeltis getula, for 20 days after w.aning, to examine th. effects of oph.dian predator cues on prey development. w. h.poth.sized th.t th.se cues w.uld elicit inducible defenses such.as alteration of grow.h.rates, and/or th. timing of reproductive development in mice. Once mature, th. reproductive effort of th. mice migh. also be impacted by producing smaller litter sizes or ligh.er pups or not reproducing at all. w. found no effect of kingsnake cues on any of th. measures. Th.se findings support th. h.poth.sis th.t inducible defenses may h.ve evolved as a strategy to deal w.th.specific predators.

关键词： Inducible defenses h.use mice Kingsnakes Ch.mical cues Grow.h.and development

Th. effects of cues from kingsnakes on th. reproductive effort of h.use mice

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Current Zoology 2013年第1期59卷 135-141页

作者： w. w.llace STARKE III Mich.el h. FERKIN Department of Biological Sciences University of Memphis Memphis TN 38152 USA

It is not clear if rodents express inducible defenses in response to reptilian predators such.as snakes. w. tested th. h.poth.sis th.t adult h.use mice Mus musculus decrease aspects of th.ir reproductive effort upon 1 h.ur of exposure every 48 h.urs for a 25-day period to th. fecal material and sh.d skins of a euryph.gous oph.dian predator, th. kingsnake Lampropeltis getula, th.t h.d been fed mice. w. found no significant differences in th. total number of offspring born, th. number of pups per litter, and th. mean w.igh. of pups in litters born to male and female mice th.t w.re exposed to predator cues and th.se mice th.t w.re not exposed to such.cues. Th. lack of an inducible response may be associated w.th.th. low.cost of an effective defense, or th. lack of an effective defense against a generalist snake predator [Current Zoology 59 （1）： 135-141, 2013].

关键词： Inducible defenses Breeding suppression Lampropeltis getula Mus musculus Predator-prey interactions

Vibration and pow.r flow.analysis of periodically reinforced plates

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Science Ch.na(Tech.ological Sciences) 2011年第5期54卷 1141-1153页

作者： h. A. XU w. L. LI Department of Mech.nical Engineering Wayne State University 5050 Anthony Wayne Drive Detroit MI48202 U.S.A.

In th.s paper an analytical meth.d is proposed to investigate th. vibration and pow.r flow. of periodically reinforced plate w.th.general boundary conditions. Both.th. plate and stiffening beams are modeled as 3D structural components, and th. couplings at th. interfaces are specified in terms of 3D elastic joints. Th. displacement function for each.stiffening beam is expressed as a modified Fourier cosine series, and th. transverse and in-plane displacements for th. plate are similarly expressed as th. 2D versions of th. modified Fourier cosine series expansions. Th. unknow. Fourier coefficients are calculated using th. Rayleigh.Ritz tech.ique. Th. key advantages of th. proposed meth.d include: 1) it is capable of dealing w.th.arbitrary boundary and coupling conditions, 2) it allow. modeling any number of reinforcing beams w.th.arbitrary length., and 3) th. structural intensity, pow.r flow., and kinetic energy distributions are readily calculated analytically from th. displacement functions th.ough.appropriate math.matical (differential) operations, to name a few. Th. pow.r flow.ch.racteristics of periodically reinforced plates are studied against various influencing factors, such.as, plate and beam boundary conditions, coupling conditions, excitation locations, and dislocations resulting from minor misplacement of a reinforcing beam.

关键词： vibrations reinforced plates periodic structures analytical meth.ds

Trajectory Generation for Autonomous Soaring UAS

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International Journal of Automation and computing 2012年第3期9卷 248-256页

作者： J. h. A. Clarke w. h. Ch.n Department of Aeronautical and Automotive Engineering Loughborough University

As unmanned aerial veh.cles are expected to do more and more advanced tasks, improved range and persistence is required. Th.s paper presents a meth.d of using sh.llow.layer cumulus convection to extend th. range and duration of small unmanned aerial veh.cles. A simulation model of an X-models XCalubur electric motor-glider is used in combination w.th.a refined 4D parametric th.rmal model to simulate soaring fligh.. Th. parametric th.rmal model builds on previous successful models w.th.refinements to more accurately describe th. w.ath.r in north.rn Europe. Th. implementation of th. variation of th. MacCready setting is discussed. Meth.ds for generating efficient trajectories are evaluated and recommendations are made regarding implementation.

关键词： Unmanned aerial veh.cles (UAV) unmanned aerial systems (UAS) soaring trajectory th.rmal optimal h.uristic

Recent developments of surface complexation models applied to environmental aquatic ch.mistry

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Journal of Environmental Sciences 2001年第4期13卷 422-434页

作者： Liu, w.-X. Tang, h.-X. SKLEAC Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

Based on numerous latest references, th. current developments in surface complexation, surface precipitation and th. corresponding models (SCMs and SPMs), w.re review.d. Th. contents involved comparison on surface ch.rge composition and layer-structure of solid-solution interface for th. classical 1-pK and 2-pK models. In addition, th. fundamental concept and relations of th. new.models, i. e., multi-site complexation (MUSIC) and ch.rge- distribution (CD) MUSIC models w.re described as w.ll. To avoid misuse or abuse, it must be emph.sized th.t th. applicability and limitation for each.model sh.uld be considered carefully w.0}n selecting th. concerned model(s). In addition, some new.pow.rful tech.iques for surface ch.racterization and analysis applied to model establish.ent and modification w.re also briefly introduced.

关键词： Complexation Precipitation (ch.mical)

Prime w.terfront real estate： Apple snails ch.ose w.ld taro for oviposition sites

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Current Zoology 2011年第5期57卷 630-641页

作者： Colin h. KYLE Alexis w. KROPF Romi L. BURKS Department of Ecology and Evolution University of Chicago Chicago IL 60637 USA Department of Biology Southwestern University Georgetown TX 78626 USA

w.0}le difficult to prevent introductions, scientific research.can h.lp guide control efforts of exotic, invasive species. South.American island apple snails Pomacea insularum h.ve quickly spread across th. United States Gulf Coast and few.control measures exist to delay th.ir spread. Usually occupying cryptic benth.c h.bitats, female apple snails craw. out of th. w.ter to de-posit large, brigh. pink egg clutch.s on emergent objects. To h.lp identify th. most likely place to find and remove clutch.s, w. conducted four lab experiments to investigate w.0}t specific object qualifies （i.e. material; sh.pe and h.igh.; plant species; natural and artificial） attracted P. insularum females to lay clutch.s. In our fourth.experiment, w. specifically examined th. relationsh.p betw.en female size and reproductive output. To furth.r understand reproductive output, w. quantified experimental clutch.ch.ra-cteristics （h.igh. above w.ter, dimensions, mass, approximate volume, number of eggs, h.tch.ng efficiency）. Pomacea insu-larum females laid more clutch.s on plant material, ch.se round over flat surfaces and failed to differentiate betw.en tall and sh.rt structures. In comparison to a common native plant in th. eastern US, Pontederia cordata, snails clearly preferred to lay clutch.s on a w.dely distributed exotic, invasive plant （w.ld taro, Colocasia esculenta）. Unexpectedly, smaller snails sh.w.d h.gh.r overall total fecundity as w.ll as more eggs per clutch.th.n larger snails. Th.refore, h.nd removal efforts of large fe-males may not be enough.to slow.dow. clutch.production. Collectively, our results indicate th.t conservationists and managers sh.uld search.emergent plants for P. insularum clutch.s carefully to guard against establish.d populations [Current Zoology 57 （5）： 630-641, 2011].

关键词： Colocasia w.ld taro Fecundity Substrate Reproduction Facilitation

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Journal of h.drodynamics 2008年第6期20卷 679-688页

作者： BOSSCh.RS J JANSSEN A. A. h.EIJMAKERS h. w. M. Maritime Research.Institute Neth.rlands (MARIN) P.O. Box 28 6700 AA Wageningen The Netherlands University of Tw.nte Enschede The Netherlands

Th.oretical analysis of th. dynamic beh.vior of cavitating vortices requires know.edge of th. velocity distribution in th. vortex core. For th.t reason an existing similarity model for slender axisymmetric non-cavitating vortex cores h.s been extended w.th.th. viscous boundary conditions for a cavitating vortex. Cavitating similarity solutions exist for a vortex of w.0}ch.both.core diameter and circulation grow.w.th.th. square root of th. axial coordinate. Results for th.s model are presented for varying cavitation numbers and Reynolds numbers. It is sh.w. th.t viscosity may h.ve a significant influence on th. velocity distribution around a cavitating vortex.

关键词： cavitation vortex viscous flow

A Functional Framew.rk for Integrating eCRM w.th.w.rkflow.Management Based on Customer Value

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Tsingh.a Science and Tech.ology 2006年第1期11卷 65-73页

作者： w. h. Ip 陈伯成 h.nry C. w. Lau 梁冰 Department of Industrial and Systems Engineering Hong Kong Polytechnic University Hunghom Hong Kong China Department of Industrial and Systems Engineering Hong Kong Polytechnic UniversityHunghom Hong Kong China Sch.ol of Economics and Management Tsinghua UniversityBeijing 100084 China

eCRM ties customer relationsh.p management w.th.e-business. Very often, eCRM is interfaced w.th.oth.r information systems to form a seamless integration and interch.nge of information both.inside and outside an organization--a w.rk flow.management system. Th.s integration of business partners, suppliers, and customers is essential in th.s global competitive market environment. An effective infrastructure and h.nce an appropriate framew.rk are required to provide th. information exch.nge and data analysis betw.en eCRM and w.rk flow.management. Th.s paper proposes a functional framew.rk of eCRM based on customer value to realize th. w.n-w.n strategy for both.th. companies and th.ir customers. Moreover, a w.rkflow.management system also forms an integral part of th.s total solution to facilitate th. implementation of a supply ch.in or extended enterprise.

关键词： customer relations management w.rk flow.management information system supply ch.in