• Title/Summary/Keyword: Taylor effect

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The Effects of CPM (Continuous Passive Motion) on Hand Function and Muscular Strength for Patients with Stroke (CPM (Continuous Passive Motion) 사용이 뇌졸중 환자의 손 기능과 근력향상에 미치는 영향)

  • Jeong, In-Seon
    • Therapeutic Science for Rehabilitation
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    • v.3 no.2
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    • pp.71-81
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    • 2014
  • Objective: The purpose of this study is to ob serve effects of CPM(Continuous Passive Motion) on hand functional and upper-extremity muscular strength rehabilitation for stroke patients. Method: Objects of this study, three patients have the symptoms of hemiplegia due to stroke. These are acute patients, within a 18 months after treatment and correspond in Brunnstrom stage 4~6. This study used single subject (A-B) design for three patients with a stroke and the effect of CPM was measured using Jebsen-Taylor hand function test, Purdue Pegboard test, hand muscular strength test. They received CPM for 3 weeks, 2 per day, 30 minutes for each, total 30 times. Results: Two patients' results of fingertip grip test in hand strength measurements did not change. Results of Jebsen-Taylor hand function test, Purdue Pegboard test and other hand muscular strength test were improved. To validate statistical results nonparametric statistical method, Wilcoxon signed ranks test was performed. P-Values are greater than 0.05 so difference between be fore and after treatment is not statistically significant result. Conclusion: Despite of limitation of short program period and fewer participants, CPM which has been conducted for stroke patients showed the effect on improvement of hand function and muscle strength. This study shows that CPM which is mainly used to treate lower-extremity rehabilitation can be use to improve performance of hand function and strength for patients with stroke.

Effect of Gas- and Liquid-injection Methods on Formation of Bubble and Liquid Slug at Merging Micro T-junction (마이크로 T자형 합류지점에서 기체 및 액체의 주입 방법이 기포 및 액체 슬러그 생성에 미치는 영향)

  • Lee, Jun Kyoung;Lee, Chi Young
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.40 no.4
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    • pp.227-236
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    • 2016
  • In the present experimental study, the effect of gas- and liquid-injected methods on the formation of bubble and liquid slug at the merging micro T-junction of a square microchannel with dimensions $600{\mu}m{\times}600{\mu}m$ was investigated. Nitrogen and water were used as test fluids. The superficial velocities of the liquid and gas were in the range of 0.05 - 1 m/s, and 0.1 - 1 m/s, respectively, where the Taylor flow was observed. The bubble length, liquid slug length, bubble velocity, and bubble generation frequency were measured by analyzing the images captured using a high-speed camera. Under similar inlet superficial velocity conditions, in the case of gas injection to the main channel at the merging T-junction (T_gas-liquid), the lengths of the bubble and liquid slug were longer, and the bubble generation frequency was lower than in the case of liquid injection to the main channel at the merging T-junction (T_liquid-gas). On the other hand, in both cases, the bubble velocity was almost the same. The previous correlation proposed using experimental data for T_liquid-gas had predicted the present experimental data of bubble length, bubble velocity, liquid slug length, and bubble generation frequency for T_gas-liquid to be ~24%, ~9%, ~39%, ~55%, respectively.

Trends in Treatment with and Mechanism of Moxibustion in Cancer Patients: A Review (암 환자에 대한 구법의 치료와 메커니즘에 대한 최신 국내외 연구 현황)

  • Yoon, Hae-chang;Kang, Ji-young;Kim, Jun-young;Joung, Jin-yong;Son, Chang-gue;Lee, Nam-heon;Cho, Jung-hyo
    • The Journal of Internal Korean Medicine
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    • v.36 no.3
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    • pp.361-379
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    • 2015
  • Objectives This study aims to review and summarize existing evidence on moxibustion treatment for cancer patients. Methods Literature published until May 2015 in international journals were searched on PubMed, CAJ (CNKI-Medicine), NDSL (National discovery for science leaders), Sage Journal, ScienceDirect, Taylor&Francis Online (HSS), and Wiley Interscience (including Blackwell); and articles in Korean journals were searched on Korean Studies Information Service System (KISS), DBPIA, E-Article, KSI e-book, New article, Korea Institute of Science and Technology Information (KISTI), and Kyobo scholar. Results We analyzed 65 relevant studies. The number of studies conducted annually has increased and most are conducted in Korea and China. Moxibustion decreases the side effects of palliative treatment, thereby synergizing with anticancer treatment; it also improves the immune system, reduces tumor factors, and relieves symptoms. The mechanism of moxibustion is multi-fold: thermo, chemo, aero and kinetic. Only the kinetic effect is not significant. It also needs a complement to moxibustion because of harmful smoke. Conclusions Thus, the effect and mechanism of moxibustion in cancer patients was reviewed. There is an unmet need to develop a model of moxibustion and test it based on Korean medicine.

The Effects of Fatigue on Cognitive Performance in Police Officers and Staff During a Forward Rotating Shift Pattern

  • Taylor, Yvonne;Merat, Natasha;Jamson, Samantha
    • Safety and Health at Work
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    • v.10 no.1
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    • pp.67-74
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    • 2019
  • Background: Few studies have examined the effects of a forward rotating shift pattern on police employee performance and well-being. This study sought to compare sleep duration, cognitive performance, and vigilance at the start and end of each shift within a three-shift, forward rotating shift pattern, common in United Kingdom police forces. Methods: Twenty-three police employee participants were recruited from North Yorkshire Police (mean age, 43 years). The participants were all working the same, 10-day, forward rotating shift pattern. No other exclusion criteria were stipulated. Sleep data were gathered using both actigraphy and self-reported methods; cognitive performance and vigilance were assessed using a customized test battery, comprising five tests: motor praxis task, visual object learning task, NBACK, digital symbol substitution task, and psychomotor vigilance test. Statistical comparisons were conducted, taking into account the shift type, shift number, and the start and end of each shift worked. Results: Sleep duration was found to be significantly reduced after night shifts. Results showed a significant main effect of shift type in the visual object learning task and NBACK task and also a significant main effect of start/end in the digital symbol substitution task, along with a number of significant interactions. Conclusion: The results of the tests indicated that learning and practice effects may have an effect on results of some of the tests. However, it is also possible that due to the fast rotating nature of the shift pattern, participants did not adjust to any particular shift; hence, their performance in the cognitive and vigilance tests did not suffer significantly as a result of this particular shift pattern.

Exploring precise deposition and influence mechanism for micro-scale serpentine structure fiber

  • Wang, Han;Ou, Weicheng;Zhong, Huiyu;He, Jingfan;Wang, Zuyong;Cai, Nian;Chen, XinDu;Xue, Zengxi;Liao, Jianxiang;Zhan, Daohua;Yao, Jingsong;Wu, Peixuan
    • Advances in nano research
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    • v.12 no.2
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    • pp.151-165
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    • 2022
  • Micro-scale serpentine structure fibers are widely used as flexible sensor in the manufacturing of micro-nano flexible electronic devices because of their outstanding non-linear mechanical properties and organizational flexibility. The use of melt electrowriting (MEW) technology, combined with the axial bending effect of the Taylor cone jet in the process, can achieve the micro-scale serpentine structure fibers. Due to the interference of the process parameters, it is still challenging to achieve the precise deposition of micro-scale and high-consistency serpentine structure fibers. In this paper, the micro-scale serpentine structure fiber is produced by MEW combined with axial bending effect. Based on the controlled deposition of MEW, applied voltage, collector speed, nozzle height and nozzle diameter are adjusted to achieve the precise deposition of micro-scale serpentine structure fibers with different morphologies in a single motion dimension. Finally, the influence mechanism of the above four parameters on the precise deposition of micro-scale serpentine fibers is explored.

The effects of Graphene Oxide flakes on the mechanical properties of cement mortar

  • Kim, Boksun;Taylor, Lawrence;Troy, Andrew;McArthur, Matthew;Ptaszynska, Monika
    • Computers and Concrete
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    • v.21 no.3
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    • pp.261-267
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    • 2018
  • This paper discusses a study of cement mortar reinforced with Graphene Oxide (GO) flakes carried out at the University of Plymouth. Over 60 specimens were prepared and tested to obtain the tensile, compressive and flexural strengths of cement mortar with/without 0.5% GO flakes by weight of cement. The dispersion of the GO flakes and the effect of the use of polycarboxylate ether superplasticizer (0.2% by weight of cement) on the material strength are discussed. Images of the particle sizes of GO are presented from the transmission electron microscopy analysis. In addition, the images from the field emission scanning electron microscope analysis are also presented to show the difference of the microscopic structure of cement mortar with/without GO. The results of the strength tests are presented. It is shown that the inclusion of the GO flakes in general led to positive results, which suggest that GO improved the tensile, compressive and flexural strengths of cement mortar.

General equations for free vibrations of thick doubly curved sandwich panels with compressible and incompressible core using higher order shear deformation theory

  • Nasihatgozar, M.;Khalili, S.M.R.;Fard, K. Malekzadeh
    • Steel and Composite Structures
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    • v.24 no.2
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    • pp.151-176
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    • 2017
  • This paper deals with general equations of motion for free vibration analysis response of thick three-layer doubly curved sandwich panels (DCSP) under simply supported boundary conditions (BCs) using higher order shear deformation theory. In this model, the face sheets are orthotropic laminated composite that follow the first order shear deformation theory (FSDT) based on Rissners-Mindlin (RM) kinematics field. The core is made of orthotropic material and its in-plane transverse displacements are modeled using the third order of the Taylor's series extension. It provides the potentiality for considering both compressible and incompressible cores. To find these equations and boundary conditions, Hamilton's principle is used. Also, the effect of trapezoidal shape factor for cross-section of curved panel element ($1{\pm}z/R$) is considered. The natural frequency parameters of DCSP are obtained using Galerkin Method. Convergence studies are performed with the appropriate formulas in general form for three-layer sandwich plate, cylindrical and spherical shells (both deep and shallow). The influences of core stiffness, ratio of core to face sheets thickness and radii of curvatures are investigated. Finally, for the first time, an optimum range for the core to face sheet stiffness ratio by considering the existence of in-plane stress which significantly affects the natural frequencies of DCSP are presented.

Experimental Study on the Vortex Flow in a Concentric Annulus with a Rotating Inner Cylinder

  • Kim, Young-Ju;Hwang, Young-Kyu
    • Journal of Mechanical Science and Technology
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    • v.17 no.4
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    • pp.562-570
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    • 2003
  • This experimental study concerns the characteristics of vortex flow in a concentric annulus with a diameter ratio of 0.52, whose outer cylinder is stationary and inner one is rotating. Pressure losses and skin friction coefficients have been measured for fully developed flows of water and of 0.4% aqueous solution of sodium carboxymethyl cellulose (CMC), respectively, when the inner cylinder rotates at the speed of 0~600 rpm. Also, the visualization of vortex flows has been performed to observe the unstable waves. The results of present study reveal the relation of the bulk flow Reynolds number Re and Rossby number Ro with respect to the skin friction coefficients. In somehow, they show the existence of flow instability mechanism. The effect of rotation on the skin friction coefficient is significantly dependent on the flow regime. The change of skin friction coefficient corresponding to the variation of rotating speed is large for the laminar flow regime, whereas it becomes smaller as Re increases for the transitional flow regime and. then, it gradually approach to zero for the turbulent flow regime. Consequently, the critical (bulk flow) Reynolds number Re$\_$c/ decreases as the rotational speed increases. Thus, the rotation of the inner cylinder promotes the onset of transition due to the excitation of Taylor vortices.

Analysis of Flexible Media Using ALE Finite Element Method (ALE 유한요소법을 이용한 유연매체의 거동해석)

  • Jee, Jung-Geun;Jang, Yong-Hoon;Park, No-Cheol;Park, Young-Pil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.247-250
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    • 2007
  • Flexible media such as the paper, the film, etc. are thin, light and very flexible. They behave in geometrically nonlinear. Any of small force makes large deformation. So we must including aerodynamic effect when its behavior is predicted. Thus, it becomes fully coupled fluid-structure interaction(FSI) problem. In FSI problems, where the fluid mesh near the structure undergoes large deformations and becomes unacceptably distorted, which drive the time step to a very small value for explicit calculations, the arbitrary Lagrangian-Eulerian(ALE) methods or rezoning are used to create a new undistorted mesh for the fluid domain, which allows the calculations to continue. In this paper, FE sheet model considering geometric nonlinearity is formulated to simulate the behavior of the flexible media. Aerodynamic force to the media by surrounding air is calculated by solving the incompressible Navier-Stokes equations. Q2Q1(Taylor-Hood) element which means biquadratic for velocity and bilinear for pressure is used for fluid domain. Q2Q1 element satisfies LBB condition and any stabilization technique is not needed. In this paper, cantilevered sheet in the viscous incompressible Navier-Stokes flow is simulated to check the mesh motion and numerical integration scheme, and then falling paper in the air is simulated and the effects of some representative parameters are investigated.

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Uncertainty Assessment using Monte Carlo Simulation in Net Thrust Measurement at AETF

  • Lee, Bo-Hwa;Lee, Kyung-Jae;Yang, In-Young;Yang, Soo-Seok;Lee, Dae-Sung
    • International Journal of Aeronautical and Space Sciences
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    • v.8 no.2
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    • pp.126-131
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    • 2007
  • In this paper, Monte Carlo Simulation (MCS) method was used as an uncertainty assessment tool for air flow, net thrust measurement. Uuncertainty sources of the net thrust measurement were analyzed, and the probability distribution characteristics of each source were discussed. Detailed MCS methodology was described including the effect of the number of simulation. Compared to the conventional sensitivity coefficient method, the MCS method has advantage in the uncertainty assessment. The MCS is comparatively simple, convenient and accurate, especially for complex or nonlinear measurement modeling equations. The uncertainty assessment result by MCS was compared with that of the conventional sensitivity coefficient method, and each method gave different result. The uncertainties in the net thrust measurement by the MCS and the conventional sensitivity coefficient method were 0.906% and 1.209%, respectively. It was concluded that the first order Taylor expansion in the conventional sensitivity coefficient method and the nonlinearity of model equation caused the difference. It was noted that the uncertainty assessment method should be selected carefully according to the mathematical characteristics of the model equation of the measurement.