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Chinese Journal of Chemical Engineering 2020年第1期28卷 23-32页

作者： Weishu Wang Yihan Liao Youzhi Yan Bingchao Zhao Tao Wang Shanshan Shangguan North China University of Water Resources and Electric Power Zhengzhou 450045China

To develop an appropriate Falling film evaporation device for organic fluid cogeneration, a numerical study on the gas–liquid two-phase counter-current flow characteristics of R113 inside a vertical tube under different structural conditions was conducted using the Fluent software. The effects of the tube length, tube diameter, and annular gap on the Falling film flow characteristics were determined, respectively. The results indicated that under a certain spray density, the Falling film thickness in the region of the steady section was almost constant with different structural parameters for the tube diameter, tube length, and annular gap. In addition, a smaller tube diameter resulted in a steadier film flow. When the tube diameter decreased to a specific value, the film thickness showed a uniform distribution along the wall surface. This indicated that a best Falling tube diameter exists. Meanwhile, the film fluctuation was enhanced with an increase in the tube length. When the tube length was greater than 1.2 m, the Falling film splashed and could not completely wet the wall surface. The film fluctuation was enhanced by decreasing the annular gap, and the film could not be formed when the annular gap was smaller than 1.2 mm.

关键词： Falling film Numerical simulation R113

Residence time distribution of high viscosity fluids Falling film flow down outside of industrial-scale vertical wavy wall: Experimental investigation and CFD prediction

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Chinese Journal of Chemical Engineering 2019年第7期27卷 1586-1594页

作者： Shichang Chen Lihao Zhang Yongjun Wang Xianming Zhang Wenxing Chen National Engineering Laboratory for Textile Fiber Materials and Processing Technology (Zhejiang) Zhejiang Sci-Tech University

The flow behavior of gravity-driven Falling film of non-conductive high viscosity polymer fluids on an industrial-scale vertical wavy wall was investigated in terms of film thickness and residence time distribution by numerical simulation and experiment.Falling film flow of high viscosity fluids was found to be steady on a vertical wavy wall in the presence of the large film thickness.The comparison between numerical simulation and experiment for the film thickness both in crest and trough of wavy wall showed good agreement.The simulation results of average residence time of Falling film flow with different viscous fluids were also consistent with the experimental results.This work provides the initial insights of how to evaluate and optimize the Falling film flow system of polymer fluid.

关键词： Falling film flow High viscosity polymer fluid Residence time distribution Film thickness Numerical simulation

Heat transfer characteristics of molten plastics in a vertical Falling film reactor

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Chinese Journal of Chemical Engineering 2019年第5期27卷 1015-1020页

作者： Zechen Jin Lijie Yin Dezhen Chen Yuanjie Jia Jun Yuan Boyang Yu Thermal and Environmental Engineering Institute Tongji UniversityShanghai 200093China Shanghai Municipal Engineering Design Institute (Group) Co. LtdShanghai 200092China

The heat transfer efficiency during the pyrolysis process is a key factor to be considered in the design of pyrolysis reactors. In this study, the average apparent heat transfer characteristics of molten plastic pyrolysis in a vertical Falling film reactor were explored by experiments and numerical simulation and the apparent heat transfer coefficients were determined. In addition, the temperature distribution and the thickness of the liquid film in the reactor were predicted and the influences of pyrolysis temperatures on the average apparent heat transfer coefficients were discussed.

关键词： Molten plastic Heat transfer Pyrolysis Vertical Falling film reactor

Tough Situations Due to Falling Ship Dismantling Quantity and Prices——Industry Economic Performance in 2018

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船舶经济贸易 2019年第6期 62-64页

作者：无 China National Shiprecycling Association (CNSA)

The 34th meeting of the 18th Central Leading Group on Deepening Reform adopted the Implementation Plan on Banning the Entry of Foreign Waste and Promoting the Reform of Solid Waste Import Management System in April 20... 详细信息

关键词： Falling Ship Dismantling Quantity Prices Industry Economic Performance

Influence of Proxies on the Reported Frequency of Falls, Fear of Falling and Activity Restriction in Older People

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Health 2014年第12期6卷 1512-1521页

作者： Elise Mendes da Costa Isabelle Godin Thierry Pepersack Michèle Dramaix Yves Coppieters Martine Bantuelle Alain Levêque Educa-Santé Non-Profit Organisation Charleroi Belgium Geriatrics Erasme University Hospital Université Libre de Bruxelles (U.L.B.) Bruxelles Belgium Research Centre in Epidemiology Biostatistics and Clinical Research School of Public Health Université Libre de Bruxelles (U.L.B.) Bruxelles Belgium Research Centre in Social Approaches to Health School of Public Health Université Libre de Bruxelles (U.L.B.) Bruxelles Belgium

Introduction: In older populations, the help of a third person may be necessary for a certain number of individuals in order to fill in questionnaires. The influence of this assistance on the collected information can raise questions, among others concerning the concordance between the information provided by the persons themselves and by their proxies, or the introduction of a potential bias. Our study’s objective is to examine, among older people, the differences in the reported frequency of falls, fear of Falling and activity restriction due to fear of Falling, according to the fact that people had filled in a questionnaire with or without the help of a third person. Methods: The data used come from the secondary analysis of a cross-sectional survey using a self-administered questionnaire and conducted in 2006 in a Belgian semi-rural town among non-institutionalised persons aged 65 years and over. Results: Among the 501 questionnaires, 16.4% were filled in with the help of another person. In bivariate analysis, the persons who needed help reported fall history, fear of Falling and activity restriction significantly more often. In multivariable analysis, when considering concurrently the covariates (sex, age, living alone and fall history for fear of Falling and for activity restriction), the influence of having received help to fill in the survey was only significant for activity restriction. Conclusion: Our study shows that it is important to know whether or not a person has received help to fill in a questionnaire. This can actually influence the reported frequency of certain outcomes, even, for activity restriction, when considering simultaneously the effect of other covariates. Given the current and future ageing of our populations, it seems that more extensive exploration is needed of the influence of proxies on the collected information about falls, fear of Falling and activity restriction among older people.

关键词： Accidental Falls Fear of Falling Activity Restriction Proxies Older People

Learning Based Falling Detection Using Multiple Doppler Sensors

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Advances in Internet of Things 2013年第2期3卷 33-43页

作者： Shoichiro Tomii Tomoaki Ohtsuki Graduate School of Science and Technology Keio University Yokohama Japan

Automated Falling detection is one of the important tasks in this ageing society. Such systems are supposed to have little interference on daily life. Doppler sensors have come to the front as useful?devices to detect human activity without using any wearable sensors. The conventional Doppler sensor based Falling detection mechanism uses the features of only one sensor. This paper presents Falling detection using multiple Doppler sensors. The resulting data from sensors are combined or selected to find out the Falling event. The combination method, using three sensors, shows 95.5% accuracy of Falling detection. Moreover, this method compensates the drawbacks of mono Doppler sensor which encounters problems when detecting movement orthogonal to irradiation directions.

关键词： Falling Detection Doppler Sensor Cepstrum Analysis SVM k-NN

Observation on the Risk of Falling and Self-efficacy in Elderly Patients with Hip Fracture

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Journal of Clinical and Nursing Research 2019年第4期3卷 5-8页

作者： Zongyou Mou Ke Song Jinquan Guo Department of Joint Surgery Dezhou People’s Hospital1751 Xinhu RoadDezhouShandong253014China

Objectives:To study the risk of Falling and self-efficacy in elderly patients with hip fracture.Methodology:Forty elderly patients with hip fractures that were caused by Falling were admitted into our hospital from April 2018 to April 2019,and were enrolled into this study.All patients were assessed by using the Morse Fall Scale(MFS)and Falls Efficacy Scale(FES).The basic situation of the patients with hip fractures caused by Falling and the scores of MFS and FES before and after Falling were evaluated.Results:Results showed that the number of patients with femoral neck fractures accounted for 70%out of all patients,and the number of patients with intertrochanteric fractures accounted for the remaining 30%of the patients.The number of patients with academic qualification below primary school is 16,the number of patients with middle high school education is 11 and the number of patients with high school education and above is 13.Slipping is the cause of hip fracture that accounted for the most in patients,followed by outing activities,whereas least patients with hip fractures was caused by Falling in nursing home.There were 29 patients’who used crutches or walking aids and this number was more than that of those who required the devices.After the MFS and FES analyses,the results(scores of MFS and FES)showed that the risk before the fall was lower.In contrast,the risk of fracture and post-surgery after the fall was greatly increased.Conclusion:The elderly patients with hip fractures were found to have increased risk of Falling and thus,these patients require good care.

关键词： elderly hip fracture risk of Falling selfefficacy

Developed Numerical Simulation of Falling and Moving Objects in Viscous Fluids under the Action of a Reynolds Lubrication Theory and Low Reynolds Numbers

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Open Journal of Fluid Dynamics 2020年第1期10卷 8-30页

作者： Seema Paul Jesper Oppelstrup Department of Scientific Computing Royal Institute of Technology Stockholm Sweden Department of Sustainable Development Environmental Science and Engineering Royal Institute of Technology Stockholm Sweden

The development work focuses on the numerical simulations of free body movement in viscous fluid. The aim is to make the simulation of very slow motion of the small body in viscous fluid. We developed bodies’ immersed dynamics simulations in viscous fluid by seeking numerical solutions for appropriate field variables. We developed the methods for vertically and spherically cylindrical objects’ motions, the forces on bodies close to a plane stationary wall are computed from the velocity and pressure fields using the Stokes equation through COMSOL Multiphysics finite element software. The Navier-Stokes equation is reduced to Stokes equation there is independence of time which means object will have an effect only on the motion and the slightly compressible flow assumption is made in order to obtain smooth solution numerically. The forces on an object in slightly compressible Stokes flow have been exerted on the Falling objects. The resulting forces have compared with analytical results from the Reynolds Lubrication Theory, and achieved significant results from the development method in Matlab and achieved significant numerical simulations in COMSOL. In addition, an investigation has been made to an object swimming at low Reynolds number. At low Reynolds number moving is possible when object scale is small and flow pattern is slow and sticky. We have developed a system for a thin two-dimensional (2D) worm-like object wiggle that is passing a wave along its centreline and its motion has simulated by the Ordinary Differential Equations (ODE) system and by the Arbitrary Lagrangian-Eulerian (ALE) moving mesh technology. The development method result shows that it is possible for the small object to have a motion from one position to another through small amplitudes and wavelengths in viscous fluid.

关键词： Slightly Compressible Stokes Equation Reynolds Lubrication Theory Falling and Moving Objects Moving Mesh Low Reynold Swimming

COSMIC DUST FROM CHANGZHOUGOU FORMATION IN JIXIAN AREA AND ITS Falling AGE

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Chinese Science Bulletin 1991年第21期36卷 1816-1819页

作者：李增慧马来斌 Tianjin Institute of Geology and Mineral Resources Tianjin 300170PRC

Ⅰ. GEOLOGICAL SETTINGS OF SAMPLING LOCALITY The sampling locality is in Changzhougou Village on the northern North China Platform. In the late Precambrian, this area seriously sank. Changzhougou Formation overlies un... 详细信息

关键词： cosmic dust fusion-type from meteorite Falling age ~40Ar/~39Ar age spectrum

Physical Activation of Elderly and the Decrease of Falling Risk

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Health 2014年第11期6卷 1116-1123页

作者： Martha Ornelas Verónica Benavides Juan F. Aguirre Gabriel Gastélum Judith M. Rodríguez-Villalobos Faculty of Physical Culture Sciences Autonomous University of Chihuahua Chihuahua México

A Physical Activation Program was designed and implemented with a particular emphasis in recovering of motor independence, and in an indirect manner;the increase of activities was carried out in a social context in such a way that it allowed isolated elderly to develop their ability to perform daily activities diminishing the burden on their caregivers. 30 people were randomly selected: 15 subjects in the experimental group and 15 in the control group;7 women and 8 men each group. Subjects aged between 60 - 84 years with a mean age of 78 years and a standard deviation of 6.5 were applied in a three-month Physical Activation Program with a 45-min daily sessions. Results obtained showed that physical activity in elderly, systematically improved their amplitude and joint mobility which impact directly and indirectly their quality of life, reducing their risk of Falling.

关键词： Physical Activation Older Adult Risk of Falling Joint Mobility