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Center of Gravity Estimation Using a Reaction board Instrumented With Fiber bragg Gratings

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Photonic Sensors 2018年第1期8卷 1-6页

作者： Rui OLIVEIRA Paulo RORIZ Manuel b. MARQUES Orlando FRAZAO INESC TEC Rua do Campo Alegre 687 4150-179 Porto Portugal CIDESD-ISMAI-Institute University of Maia (ISMAl) Av. Carlos Oliveira Campos Castelo da Maia 4475-690 MaiaPortugal Department of Physics and Astronomy Faculty of Sciences University of Porto Rua do Campo Alegre 687 4169-007Porto Portugal

The purpose of the present work is to construct a reaction board based on fiber bragg gratings （FbGs） that could be used for estimation of the 2D coordinates of the projection of center of gravity （CG） of an object. The apparatus is consisted of a rigid equilateral triangular board mounted on three supports at the vertices, two of which have cantilevers instrumented with FbGs. When an object of known weight is placed on the board, the bending strain of the cantilevers is measured by a proportional wavelength shift of the FbGs. Applying the equilibrium conditions of a rigid body and proper calibration procedures, the wavelength shift is used to estimate the vertical reaction forces and moments of force at the supports and the coordinates of the object＇s CG projection on the board. This method can be used on a regular basis to estimate the CG of the human body or objects with complex geometry and density distribution. An example is provided for the estimation of the CG projection coordinates of two orthopaedic femur bone models, one intact, and the other with a hip stem implant encased. The clinical implications of changing the normal CG location by means of a prosthesis have been discussed.

关键词： Optical fiber sensors fiber bragg gratings cantilever center of gravity hip prosthesis

Comparison of Cox Model Methods in A Low-dimensional Setting with Few Events

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Genomics, Proteomics & bioinformatics 2016年第4期14卷 235-243页

作者： Francisco M. Ojeda Christian Miiller Daniela bornigen David-Alexandre Tregouet Arne Schillert Matthias Heinig Tanja Zeller Renate b. Schnabel Department of General and Interventional Cardiology University Heart Center Hamburg-Eppendorf 20246 Hamburg Germany German Center for Cardiovascular Research (DZHK) Hamburg |Kiel| Luebeck Germany Sorbonne Universites University Pierre et Marie Curie Paris 06 Institut National pour la Sante et la Recherche Medicale (INSERM) Unite Mixte de Recherche en Sante (UMR_S) 1166 F-75013 Paris France Institute for Cardiometaholism and Nutrition (ICAN) F-75013 Paris France Institut fur Medizinische biometrie und Statistik Universitat zu Lubeck Universitatsklinikum Schleswig-Holstein Campus Lubeck 23562 Lubeck Germany Institute of Computational biology German Research Center for Environmental Health Helmholtz Zentrum Munchen 85764 Neuherberg Germany

Prognostic models based on survival data frequently make use of the Cox proportional hazards model. Developing reliable Cox models with few events relative to the number of predictors can be challenging, even in low-dimensional datasets, with a much larger number of observations than variables. In such a setting we examined the performance of methods used to estimate a Cox model, including （i） full model using all available predictors and estimated by standard techniques, （ii） backward elimination （bE）, （iii） ridge regression, （iv） least absolute shrinkage and selection operator （lasso）, and （v） elastic net. based on a prospective cohort of patients with manifest coronary artery disease （CAD）, we performed a simulation study to compare the predictive accuracy, calibration, and discrimination of these approaches, Candidate predictors for incident cardiovascular events we used included clinical variables, biomarkers, and a selection of genetic variants associated with CAD. The penalized methods, i.e., ridge, lasso, and elastic net, showed a comparable performance, in terms of predictive accuracy, calibration, and discrimination, and outperformed bE and the full model. Excessive shrinkage was observed in some cases for the penalized methods, mostly on the simulation scenarios having the lowest ratio of a number of events to the number of variables. We conclude that in similar settings, these three penalized methods can be used interchangeably. The full model and backward elimination are not recommended in rare event scenarios.

关键词： Proportional hazards regression Penalized regression Events per variable Coronary artery disease

Increasing prevalence of asthma and allergy in beijing pre-school children: Is exclusive breastfeeding for more than 6 months protective?

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Chinese Science bulletin 2013年第25期58卷 4190-4202页

作者： QU Fang WESCHLER Louise b. SUNDELL Jan ZHANG YinPing Department of building Science Tsinghua University

This study evaluated the prevalence and risk factors for asthma,allergy and related symptoms;and breastfeeding patterns and durations for 5479 beijing children aged 3–*** of children in randomly selected kindergartens wrote responses to a questionnaire used *** study aimed to evaluate trends in the prevalence of asthma and related illnesses,and to determine whether"more"breastfeeding,defined as exclusive,>6 months,was associated with reduced *** has increased in this age group between 1990 and 2011,with the steepest increase in the last 2–3 *** the total,14.2%(779)children were breastfed exclusively for>6 *** efficacy of"more"breastfeeding was tested in a subset with two strong risk factors,positive family history(for asthma and/or allergy)and male gender."More"breastfeeding was found to be significantly protective(aOR 0.42,Pbset against Doctor-diagnosed asthma(D-asthma).Protection that did not reach statistical significance was also found for this subset against Wheeze ever,Cough at night,Rhinitis ever,Doctor-diagnosed rhinitis(D-rhinitis)and *** greatest protective effects were found for girls with no family history of asthma or allergy,reaching statistical significance for Wheeze ever(aOR 0.48,Pbreastfeeding was not consistently associated with either a protective or risk effect for Eczema.

关键词：母乳喂养保护作用学前儿童患病率哮喘过敏北京风险因素

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加拉帕戈斯群岛同域达尔文雀种群的进化动态(英文)

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动物学报 2004年第6期50卷 936-941页

作者： b.Rosemary GRANT Department of Ecology and Evolutionary biology Princeton UniversityPrincetonNew Jersey 08544USA

本文主要论述物种形成的三个阶段 :建群、线形分异和生殖隔离。首先介绍一项通过时间产生分异的调查 ,然后检测种群间基因交流的障碍 ,最后描述一个自然事件从而分析建群过程。本项工作是在加拉帕戈斯群岛中的达芬梅杰岛上长期研究达尔... 详细信息

本文主要论述物种形成的三个阶段 :建群、线形分异和生殖隔离。首先介绍一项通过时间产生分异的调查 ,然后检测种群间基因交流的障碍 ,最后描述一个自然事件从而分析建群过程。本项工作是在加拉帕戈斯群岛中的达芬梅杰岛上长期研究达尔文雀进化工作的一部分 ,研究组成员由格兰特、笔者和其他同事组成。岛上发生适应辐射的时间并不长 ,现存的 1 4种达尔文雀由 2 0 0或 3 0 0万年前的一个祖先分化而成。极端的年间气候波动改变了达尔文雀的生态条件和食物供给。达尔文雀种群受到这些变化的影响 ,通过重复的进化反应 ,发生了自然选择。通过 3 0年的积累 ,中地雀 (Ｇｅｏｓｐｉｚａｆｏｒｔｉｓ)和仙人掌地雀 (Ｇ .ｓｃａｎｄｅｎｓ)种群的体型大小和喙部形状发生了显著的变化。达尔文雀的鸣叫是在幼鸟时期通过学习而形成的 ,类似于印痕过程 ,鸣叫对保持种间的生殖隔离起着一定的作用。但是在一些特殊的生态条件下 ,生殖隔离可以被由于错误印痕所形成的鸣叫而冲破 ,导致种间杂交和基因渗入 ,当然 ,这种情况非常罕见。自然选择可以使基因流从一个物种流动到另一个物种从而增加变异。 1 983年 ,大地雀 (Ｇ .ｍａｇｎｉｒｏｓｔｒｉｓ)在达芬梅杰岛上建群。最初岛上只有拥有共同亲鸟的 2只雄鸟和

关键词：达尔文生殖隔离种群进化加拉帕戈斯群岛物种形成自然选择生态条件种间杂交近亲繁殖

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磁场对液体-微伸缩固体介面波传播的影响

应用数学和力学 2011年第5期32卷 563-569页

作者： b.辛格政府学院研究生院数学系

在一个传播理想的非粘性液体半空间,和一个传播理想的微伸缩弹性固体半空间之间,研究介面处纵波的反射和透射.在两个半空间中,满足介面处必需的边界条件下,得到控制方程的适当解,是一组以不同反射和透射波振幅比表示的5个非齐次方程.以... 详细信息

在一个传播理想的非粘性液体半空间,和一个传播理想的微伸缩弹性固体半空间之间,研究介面处纵波的反射和透射.在两个半空间中,满足介面处必需的边界条件下,得到控制方程的适当解,是一组以不同反射和透射波振幅比表示的5个非齐次方程.以水和铝-环氧树脂合成材料介面为实际例子,用Gauss消除法的Fortran程序求解方程组.考虑存在和不存在外加横向磁场两种情况,在某些入射角范围内,计算振幅比的数值解.最后用图形给出横向磁场对不同反射和透射波振幅比的影响.

关键词：微伸缩波的传播反射和透射磁场

荧光读取多层CD光盘(CDLROM)的研制原理

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感光科学与光化学 2003年第4期21卷 285-295页

作者： b.I.Shapiro 俄罗斯国家照相化学设计研究院科研中心

本文研究了在卤化银光敏层的基础上构建多层CD盘的原理,研制了将影像中的银转化为产生荧光产物的方法,从而在应用荧光读取信息时可极大地提高其信噪比.研究后作者得出结论,传统的卤化银照相术能在制造多层光盘CDLROM中得到应用.

关键词：多层光盘CDLROM 荧光读取卤化银光敏层信噪比

荷兰花卉业的成功因素:产业链内的合作和新技术的运用(英文)

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北京林业大学学报 2004年第S1期26卷 4-9页

作者： Peter b. Visser 西班牙瓦伦西亚大学地中海农林复合体研究所瓦伦西亚46022

荷兰的鲜花和观赏植物现在销售到全世界。这些产品或由荷兰生产 ,或由他国进口通过荷兰著名花卉拍卖行而进入市场。荷兰花卉产业以其生产链之良好组织为特色 ,并以研究、育种、生产和国内外贸易为其支撑。为了在国际化、分散化的花卉贸... 详细信息

荷兰的鲜花和观赏植物现在销售到全世界。这些产品或由荷兰生产 ,或由他国进口通过荷兰著名花卉拍卖行而进入市场。荷兰花卉产业以其生产链之良好组织为特色 ,并以研究、育种、生产和国内外贸易为其支撑。为了在国际化、分散化的花卉贸易新发展趋势中及在与热带国家花卉生产竞争中保持领先地位 ,有关部门仍致力于加强生产链 ,保证产品之优异品质 ,运用现代物流和电子商业贸易以及新型育种工程等适应性协作措施。文中提出在有关部门中加强内部协作和在公司中应用遗传工程作为育种手段之必要性。最后 ,提供了几项遗传工程在花卉育种之成功例证。

关键词：产业链新技术例证

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互联网资源的评价与利用

国外社会科学 2002年第6期 105-106页

作者： b.格伦 b.吉纳丹

互联网是一种新的资源.许多教师目前仍然在摸索网络资源利用的方法.对高校的英语教师的调查发现,对互联网资源的利用有人赞同,也有人反对.

关键词：限制检索互联网资源网络资源图书出版物网站布尔逻辑

CONTROL OF STRONG SHOCK—TURbULENT bOUNDARY LAYER INTERACTION IN RECTANGULAR CHANNELS

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Chinese Journal of Aeronautics 1992年第1期 5-11页

作者： He Z W, Li F b (Nanjing Aeronautical Institute, Nanjing, 210016)

Under initial conditions of Ma= 1.63 and δ= 5.65mm, the controlling techniquesof strong shock-turbulent boundary layer interactions in rectangular channels are investigatedsystematically in this paper. It is found that for an effective improvement on boundarylayer parameters and reducing the turbulence level of flow downstream ofshock-boundary layer interaction, the bleed mass flow G = 2～2.5%, and the width of suctionslot W/δ= 0.88 and its position of L / δ= 1.77 are the most suitable values amongthe G, W /δ, L/ δand b studied. Experiments reveal that for improving the steadyand dynamic characteristics of flow in the channels it is necessary for channels with highvalue of bto control effectively the strong shock-boundary layer interaction.

关键词： CONTROL OF STRONG SHOCK TURbULENT bOUNDARY LAYER INTERACTION IN RECTANGULAR CHANNELS