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Adaptive inverse control of random vibration based on the filtered-X LMS algorithm

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 141-146页

作者： Yang Zhidong,Huang Qitao~(++),Han Junwei~§and Li Hongren~§National Key Laboratory of Robots Technique and System,Harbin Institute of Technology,Harbin 150080,China phd Candidate ~++ phd ~§Professor National Key Laboratory of Robots Technique and System Harbin Institute of Technology Harbin China

Random vibration control is aimed at reproducing the power spectral density （PSD） at specified control points. The classical frequency-spectrum equalization algorithm needs to compute the average of the multiple frequency response functions （FRFs）, which lengthens the control loop time in the equalization process. Likewise, the feedback control algorithm has a very slow convergence rate due to the small value of the feedback gain parameter to ensure stability of the system. To overcome these limitations, an adaptive inverse control of random vibrations based on the filtered-X least mean-square （LMS） algorithm is proposed. Furthermore, according to the description and iteration characteristics of random vibration tests in the frequency domain, the frequency domain LMS algorithm is adopted to refine the inverse characteristics of the FRF instead of the traditional time domain LMS algorithm. This inverse characteristic, which is called the impedance function of the system under control, is used to update the drive PSD directly. The test results indicated that in addition to successfully avoiding the instability problem that occurs during the iteration process, the adaptive control strategy minimizes the amount of time needed to obtain a short control loop and achieve equalization.

关键词： random vibration power spectral density frequency response function adaptive inverse control filtered-X LMS algorithm

New Concepts and Evidence Based Practice in Physiotherapy：Examples from Stroke Rehabilitation

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中国康复医学杂志 2011年第1期26卷 6-12页

作者： Langhammer Birgitta, RPT, phd Oslo University College and Sunnaas Rehabilitation Hospital

Objective:The purpose of this paper is to give an overview of new concepts and evidence based physiotherapy practice in stroke rehabilitation in the acute,post acute and chronic stage of stroke. Background:Historically physiotherapy has developed through the years from a focus on health,beauty,and equilibrium between spiritual,moral and physical powers,to a client centered service to people and populations to develop,to maintain and to restore maximum movement and functional ability throughout the lifespan. Still the health perspective is strong and divided into first,second and third prophylaxis. New concepts like Evidence Based Medicine,Evidence Based Practice,International Classification of Function and research within neurophysiology have had a deep impact on physiotherapy services,practice and education. The highest levels of documentation are Meta analyses and Randomised Controlled Trials,and today many of the physiotherapy methods used in rehabilitation of neurological conditions are tried out in different trials,bringing up-to date knowledge into practice. This paper focuses on rehabilitation of persons with stroke and physiotherapy methods in particular. Result:Physiotherapy in the acute stage improves motor function and enhances mobility. Rehabilitative efforts within the first few weeks as opposed to later favors better recovery. Type of physiotherapy in the acute stage is task oriented training with a focus on intensity and variability. Post acute therapy-based rehabilitation services targeted towards stroke patients living at home appear to improve independence in personal activities of daily living. In the chronic stage there is good evidence that aerobic exercise is beneficial for improving aerobic capacity in people with mild and moderate stroke. Progressive resistance strength training programmes reduce musculoskeletal impairment after stroke,without increasing tone or spasticity.

关键词：《中国康复医学杂志》期刊编辑部编辑工作

ALTERATION IN ENTEROCYTE GENE EXPRESSION MAY EXPLAIN STRUCTURAL AND FUNCTIONAL CHANGES FOLLOWING GLUTAMINE SUPPLEMENTED PARENTERAL NUTRITION

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Chinese Medical Sciences Journal 1999年第2期14卷 112-116页

作者： JiangZhuming,MD LiuYuewu,MD,phd MaYongxian,MD BaiManxi,MD,phd QiangBoqing,phd RobertSmith,MD DepartmentofSurgery PekingUnionMedicalCollegeHospitalBeijing100730 MolecularBiologyLaboratoryofChineseAcademyofMedicalSciences Beijing100730 JoslinDiabeticCenter DepartmentofSurgeryMassachusettsGeneralHospitalandBrighamandWomen＇sHospitalHarvardMedicalSchool

Following extensive bowel resection, the intestinal tract undergoes a variety of adaptive responses to enhance bowel function. The purpose of this study was to determine the effect of glutamine-supplemented parenteral nutrition on mucosal cellularity and gut function. In addition, enterocyte gene expression of two relevant systems was also characterized and related to the structural and functional changes that occurred. Male Wistar rats underwent a 60% small bowel resection and jugular vein catheterization and were randomized into two groups. The control group (n = 10) received a standard intravenous nutritional solution and the study group (n = 10) received a similar solution but enriched with alanylglutamine dipeptide. After 7 days blood was taken for amino acid analysis, and bowel was harvested to determine mucosal morphology and expression of mucosal cell glutaminase and IGF-I mRNA. Mesentery lymphnodes were cultured to determine the presence of bacteria and thus access bacteria translocation. Serum glutamine concentration and mucosal architecture were maintained in the study group compared to the controls. Seventy percent of lymphnodes were cultured positive in control vs. only 20% in the study group (P

关键词： Parenteral Nutrition Animals Dipeptides Enterocytes Gene Expression Glutaminase Ileum Insulin-Like Growth Factor I Intestinal Mucosa Intestine, Small Jejunum Male RNA, Messenger Rats Rats, Wistar Research Support, Non-U.S. Gov't

Carbohydrate Supplementation during Exercise：Does It Help？How Much is Too Much？

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中国运动医学杂志 2008年第4期27卷 518-527页

作者： Asker Jeukendrup, phd Human Performance Laboratory School of Sport and Exercise Sciences University of Birmingham Birmingham UNITED KINGDOM

KEY POINTS· Carbohydrate intake during exercise can delay the onset of fatigue and improve performance of prolonged exercise as well as exercise of shorter duration and greater intensity (e.g., continuous exercise lasting about 1h and intermittent high-intensity exercise), but the mechanisms by which performance is improved are different.

关键词：碳水化合物体育运动保健知识营养成分

JIPB in 2010-A More Reader-Friendly International Journal

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Journal of Integrative Plant Biology 2010年第1期52卷 2-3页

作者： Chun-Ming Liu, phd Editor-in-Chief, JIPB 机构不详

Online publication and online reading are gradually becoming routine for scientists and students. Most researchers now follow the scientific development in their expertise area through PubMed, Google Scholar, E-alert and Faculty 1000, etc. This in turn will bring changes to the way of scientific publishing. In JIPB＇s case, we have seen a sharp increase of the number of downloads and online subscriptions during the last couple of years, compared to a rather stable hardcopy subscription rate for the same period.

关键词： Reader In 2010 JIPB in 2010-A More Reader-Friendly International Journal

New perspectives on the prevention of myopia

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Eye Science 2011年第1期26卷 3-8页

作者： Fan Xiang MD Ian G. Morgan phd Mingguang He MD phd Department of Preventive Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou China ARC Centre of Excellence in Vision Science Research School of Biology College of Medicine Biology and the Environment Australian National University Canberra Australia

The high prevalence of myopia and its public health and clinical consequences make prevention of myopia a top *** approaches to prevention have been based on reducing accommodative load,and have generally been *** treatment with atropine eye-drops has produced clinically significant effects,.which are however of limited duration and suffer from potential *** addition,based on animal experimentation,.it is now clear that atropine blocks eye growth by mechanisms which do not involve accommodation..More generally,.experimentation on animal models of myopia has shown that accommodation is not im-portant for the control of eye growth,whereas exposure to hyperopic (growth-promoting) and myopic (growth-inhibit-ing) defocus is more *** epidemiological evi-dence has also questioned the importance of near work,al-though education is clearly *** suggests a preven-tive approach based on deliberately increasing the amount of myopic defocus a child is exposed to may be *** is also convincing evidence that children who spend more time outside are less likely to become myopic,which also suggests a quite non-invasive approach to *** new directions need to be pursued.

关键词：近视预防临床效果动物实验公众健康模型实验生长控制生长抑制

Diagnosis and treatment of gastroesophageal reflux disease in infants and children

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World Journal of Gastroenterology 1999年第5期5卷 375-382页

作者： Yvan Vandenplas(phd.,Academic Children’s Hospital,Free University of Brussels,Laarbeeklaan 101) Vrije Universiteit Brussel 比利时

Does A High-Carbohydrate Breakfast Improve Performance？

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中国运动医学杂志 2009年第1期28卷 88-96页

作者： Clyde Williams phd FACSM David Lamb FACSM

KEY POINTS·Fatigue during prolonged heavy exercise is often associated with low or depleted muscle glycogen stores and with lowered blood glucose.·Eating a high-carbohydrate meal 2-4 h before constant-pace exercise can improve endurance capacity (time to exhaustion) but may not be advantageous in time-trials,especially if sports drinks are consumed during the trials.·Contrary to earlier reports,there appear to be no adverse effects on endurance capacity of consuming well-formulated carbohydrate solutions within the hour before exercise.

关键词：运动医学锻炼习惯运动疲劳恢复措施体育运动

Diffraction of plane SV waves by a cavity in poroelastic half-space

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 29-46页

作者： Liang Jianwen and Liu Zhongxian Department of Civil Engineering, Tianjin University, Tianjin 300072, China Professor phd Candidate Department of Civil Engineering Tianjin University Tianjin China

This paper presents an indirect boundary integration equation method for diffraction of plane SV waves by a 2-D cavity in a poroelastic *** Green＇s functions of compressive and shear wave sources are derived based on Biot＇s theory. The scattered waves are constructed using fictitious wave sources close to the boundary of the cavity, and their magnitudes are determined by the boundary conditions. Verification of the accuracy is performed by：（1） checking the satisfaction extent of the boundary conditions, （2） comparing the degenerated solutions of a single-phased case with well- known solutions, and （3） examining the numerical stability of the solutions. The nature of diffraction of plane SV waves around a cavity in a poroelastic half-space is investigated by numerical examples.

关键词： poroelastic half-space cavity diffraction plane SV waves compressive wave source shear wave source Green's function pore pressure