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Wearable monitors criterion validity for energy expenditure in sedentary and light activities

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journal of Sport and Health Science 2017年第1期6卷 103-110页

作者： Florez-Pregonero Alberto Meckes nathanael Buman Mathew Barbara e.Ainsworth Departamento de Formación Facultad de EducaciónPontificia Universidad JaverianaBogotaDistrito Capital 11001000Colombia Department of exercise and Sport Science School of Behavioral and Applied SciencesAzuza Pacific UniversityAzuzaCA 91702USA School of Nutrition and Health Promotion Arizona State UniversityPhoenixAZ 85004USA

Background: Wearable monitors(WMs) are used to estimate the time spent in sedentary behaviors(SBs) and light-intensity physical activities(lPAs) and their associated energy cost; however, the accuracy of WMs in measuring behaviors on the lower end of the intensity spectrum is unclear. The aim of this study was to assess the validity of 3 WMs(Acti Graph GT3X+; activ PAl, and Sense Wear 2) in estimating the intensity of SB and lPA in adults as compared with the criterion measure of oxygen uptake(VO_2) measured by indirect ***: Sixteen participants(age: 25.38 ± 8.58 years) wore the ActiG raph GT3X+, activP Al, and SenseW ear 2 devices during 7 sedentary-to-light activities. VO_2(ml/kg/min) was estimated by means of a portable gas analyzer, Oxycon Mobile(Carefusion, Yorba linda, CA, USA). All data were transformed into metabolic equivalents and analyzed using mean percentage error, equivalence plots, Bland-Altman plots, kappa statistics, and sensitivity/***: Mean percentage error was lowest for the activ PAl for SB(14.9%) and lPA(9.3%) compared with other WMs, which were >21.2%.None of the WMs fell within the equivalency range of ±10% of the criterion mean value. Bland-Altman plots revealed narrower levels of agreement with all WMs for SB than for lPA. Kappa statistics were low for all WMs, and sensitivity and specificity varied by WM ***: None of the WMs tested in this study were equivalent with the criterion measure(VO_2) in estimating sedentary-to-light activities;however, the activ PAl had greater overall accuracy in measuring SB and lPA than did the Acti Graph and Sense Wear 2 monitors.

关键词： Accelerometers Accuracy low intensity Metabolic estimations Objective measurement Sedentary behaviors

Fish embryo and juvenile size under hypoxia in the mouth- brooding African cichlid Pseudocrenilabrus multicolor

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Current Zoology 2012年第3期58卷 401-412页

作者： e.e. ReARDON l.j. CHAPMAN Department of Biology McGill University 1205 Dr. Penfield Ave Montreal Quebec H3A 1B 1 Canada Wildlife Conservation Society 2300 Southern Boulevard Bronx NY 10460 USA

We used a field survey and a laboratory rearing experiment to （a） examine response （size and survival） to life-long hypoxia in offspring of the African maternal mouth-brooding cichlid Pseudocrenilabrus multicolor victoriae （Seegers） and （b） explore the degree to which developmental response can be environmentaUy-induced. embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen （DO） concentrations. In the laboratory, first generation （F1） broods of low-DO origin were reared under high or low DO. Brooding period was quantified for the mothers; and egg size, egg metabolic rate and juvenile size-at-release were quantified in their （F2） offspring. The F2 offspring were split and grown for 3 months post-release under high or low DO, and juvenile size and survival were quantified. In the field survey, across stages, embryos from low-DO field populations were shorter and weighed less than embryos from high-DO populations. In the laboratory experi- ment, F2 eggs and juveniles-at-release from mother＇s mouth did not differ in mass, length, survival regardless of development DO environment. However, juveniles diverged in size after leaving mother＇s mouth, exhibiting smaller size when grown under low DO. Size differences in embryo size across field populations and divergence in embryo size after release from the mother＇s mouth support predictions for smaller body size under hypoxia. There was no evidence for negative effects on survival of juveniles after 3 months. Brooding period was 16% shorter in females reared under low DO suggesting that hypoxia may accelerate embryo de- velopment. This work provides insights into how bearer fishes respond to hypoxic stress relative to fishes with no post-spawning parental care; a shorter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under hypoxia in brooding fishes [Current Zoology 58 （3）： 401-412, 2012].

关键词： African cichlid lake Victoria life-history Parental care Dissolved oxygen

Numerical studies towards practical large-eddy simulation

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journal of Thermal Science 2007年第4期16卷 328-336页

作者： j.Boudet j.Caro l.Shao e.lév(?)que lMFA laboratoire

large-eddy simulation developments and validations are presented for an improved simulation of turbulent internal flows. Numerical methods are proposed according to two competing criteria： numerical qualities （precision and spectral characteristics）, and adaptability to complex configurations. First, methods are tested on academic test-cases, in order to abridge with fundamental studies. Consistent results are obtained using adaptable finite volume method, with higher order advection fluxes, implicit grid filtering and ＂low-cost＂ shear-improved Smagorinsky model. This analysis particularly focuses on mean flow, fluctuations, two-point correlations and spectra. Moreover, it is shown that exponential averaging is a promising tool for leS implementation in complex geometry with deterministic unsteadiness. Finally, adaptability of the method is demonstrated by application to a configuration representative of blade-tip clearance flow in a turbomachine.

关键词： leS adaptable methods validation

GUIDeD WAVeS IN MUlTIlAYeReD PlATeS: AN IMPROVeD ORTHOGONAl POlYNOMIAl APPROACH

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Acta Mechanica Solida Sinica 2014年第5期27卷 542-550页

作者： jiangong Yu j.e.lefebvre l.elmaimouni School of Mechanical and Power engineering Henan Polytechnic University Department of Civil engineering University of Siegen Univ lille Nord de France F-59000 Lille France UVHC IEMN-DOAE F-59313 Valenciennes Cedex 9 France CNRS UMR 8520 F-59650 Villeneuve d’Ascq France eRSITA Faculte Polydisciplinaire d’Ouarzazate Univ. Ibn Zohr 45000 Ouarzazate Morocco lMTI Faculte des Sciences d’Agadir Universite Ibn Zohr BP 28/S Agadir Morocco

Conventional orthogonal polynomial approach can solve the multilayered plate only when the material properties of two adjacent layers do not change significantly. This paper de- veloped an improved orthogonal polynomial approach to solve wave propagation in multilayered plates with very dissimilar material properties. Through numerical comparisons among the exact solution, the results from the conventional polynomial approach and from the improved poly- nomial approach, the validity of the improved polynomial approach is illustrated. Finally, it is shown that the conventional polynomial approach can not yield correct continuous normal stress profiles. The improved orthogonul polynomial approach has overcome this drawback.

关键词： multilayered plate orthogonal polynomial dispersion curves stress profiles

estimating long-term K-12 student homelessness after a catastrophic flood disaster

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Resilient Cities and Structures 2023年第2期2卷 82-92页

作者： Ram Krishna Mazumder SAmin enderami nathanael Rosenheim elaina j.Sutley Michelle Stanley Michelle Meyer Arcadis U.S.Inc United States Department of Civil Environmental and Architectural EngineeringUniversity of KansasUnited States Department of landscape Architecture and Urban Planning Texas A&M UniversityUnited States

Despite efforts to end homelessness in the United States,student homelessness is gradually growing over the past *** creates physical and psychological disadvantages for students and often disrupts school *** suggests that students who experience prolonged dislocation and school disruption after a dis-aster are primarily from low-income households and under-resourced *** study develops a framework to predict post-disaster trajectories for kindergarten through high school(K-12)students faced with a major disaster;the framework includes an estimation on the households with children who recover and those who experience long-term *** the National Center for education Statistics school attendance boundaries,resi-dential housing inventory,and *** data,the framework first identifies students within school boundaries and links schools to students to *** framework then estimates dislocation induced by the disaster sce-nario and tracks the stage of post-disaster housing for each dislocated *** recovery of dislocated students is predicted using a multi-state Markov chain model,which captures the sequences that households transition through the four stages of post-disaster housing(i.e.,emergency shelter,temporary shelter,temporary housing,and permanent housing)based on the social vulnerability of the ***,the framework predicts the number of students experiencing long-term homelessness and maps the students back to their pre-disaster *** proposed framework is exemplified for the case of Hurricane Matthew-induced flooding in lumberton,North *** highlight the disparate outcomes households with children face after major disasters and can be used to aid decision-making to reduce future disaster impacts on students.

关键词： Housing recovery Vacancy Recovery sequence Relocation Social vulnerability

ＣＯＭＰＬＥＸＩＴＹＯＦＬＡＲＧＥＴＩＭＥＢＥＨＡＶＩＯＵＲＯＦＥＶＯＬＵＴＩＯＮＥＱＵＡＴＩＯＮＳＷＩＴＨＢＯＵＮＤＥＤＤＡＴＡ

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Chinese Annals of Mathematics,Series B 2002年第2期23卷 293-310页

作者： j.l.VZQUeZ e.ZUAZUA Departamento de Matematicas Universidad AutonomaDepartamento de Matematica AplicadaUniversidadComplutense 28049MadridSpain28040 M

The authors study the asymptotic behaviour of solutions of the heat equation and a number of evolution equations using scaling techniques. It is proved that in the framework of bounded data stabilization need not occur and the general asymptotic behaviour is complex. This behaviour reflects for large times, even on compact sets, the complexity of the initial data at infinity.

关键词： Asymptotic behaviour Scaling Omega-limit Heat equation Hyperbolic conservation laws

Fully Kinetic, electromagnetic Particle-in-Cell Simulations of Plasma Microturbulence

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Communications in Computational Physics 2007年第4期2卷 684-722页

作者： j.l.V.lewandowski l.e.Zakharov Plasma Physics laboratory Princeton UniversityP.O.Box 451PrincetonNJ 08543USA.

A novel numerical method,based on physical intuition,for particle-in-cell simulations of electromagnetic plasma microturbulence with fully kinetic ion and electron dynamics is *** method is based on the observation that,for lowfrequency modes of interest[ω/ω_(ci)≪1,ωis the typical mode frequency andωci is the ion cyclotron frequency]the impact of particles that have velocities larger than the resonant velocity,v^(r)∼ω/k_(||)(k_(||) is the typical parallel wavenumber)is negligibly small(this is especially true for the electrons).Therefore it is natural to analytically segregate the electron response into an adiabatic response and a nonadiabatic response and to numerically resolve only the latter:this approach is termed the splitting ***,the exact separation between adiabatic and nonadiabatic responses implies that a set of coupled,nonlinear elliptic equations has to be solved;in this paper an iterative technique based on the multigrid method is used to resolve the apparent numerical *** is shown that the splitting scheme allows for clean,noise-free simulations of electromagnetic drift waves and ion temperature gradient(ITG)*** is also shown that the advantage of noise-free kinetic simulations translates into better energy conservation properties.

关键词： Plasma micro-turbulence particle-in-cell simulation multigrid solver.

Sediment Pollution Assessment of Abandoned Residential Developments Using Remote Sensing and GIS

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Pedosphere 2013年第1期23卷 39-47页

作者： j.D.WeRTS e.A.MIKHAIlOVA C.j.POST j.l.SHARP Department of Forestry and Natural Resources Clemson University 261 Lehotsky HallClemson SC 29634 (USA) Department of Mathematical Sciences Clemson University 234 Barre HallClemson SC 29634 (USA)

The current economic crisis has left numerous residential developments in the southeastern United States in various stages of construction. Many of them are currently graded and essentially abandoned, creating a major source of sediment runoff to waterways. Residential development locations with significant bare soil areas were identified through classification of landsat 5 TM satellite imagery and subsequently verified from high-resolution county aerial photographs. The revised universal soil loss equation (RUSle) was used in a geographic information system (GIS) as a tool for prioritizing identified locations on the basis of potential soil loss assuming the worst case scenario of a completely unmaintained site. Initial GIS identification indicated 301 sites with a total bare soil area of 2 378 ha over three counties in Upstate South Carolina. A random sample of 153 sites was visited over 17 days and assessed using a mobile GIS, global positioning system (GPS), and digital camera for field validation. Results indicated that 78% (119) of the sites were classified correctly (residential construction sites in varying stages of completion); 88% of identified areas were less than 25% built compared to the previous year; 48% were categorized as moderate to severe problems. Abandoned and unfinished developments in Upstate South Carolina may represent a major source of sediment pollution to streams. Well-maintained erosion control devices may be useful in preventing offsite sedimentation.

关键词： classification construction erosion RUSle soil loss

ReITeRATeD HOMOGeNIZATION OF NONlINeAR MONOTONe OPeRATORS

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Chinese Annals of Mathematics,Series B 2001年第1期22卷 1-12页

作者： j.l.lIONS D.lUKKASSeN l.e.PeRSSON P.WAll CollegedeFrance 3rued＇Ulm75231Pariscedex05France NarvikInstituteofTechnologyandNorutTechnologyltd. N-8505NarvikNorway DepartmentofMathematics LuleaUniversityofTechnologyS-97187LuleaSweden

In this paper, the authors study reiterated homogenization of nonlinear equations of the form --div(a(x, x/ε x/ε, Duε) = f, where a is periodic in the first two arguments and monotone in the third. It is proved that ue converges weakly in W1,P(Ω) (and even in some multiscale sense), as ε→ 0 to the solution uo of a limit problem. Moreover, an explicit expression for the limit problem is given. The main results were also stated in [15]. This article presents the complete proofs of these results.

关键词： Homogenization Nonlinear monotone operators Nonlinear equation