• 제목/요약/키워드: single equation

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물리치료사의 환자 운반 시 작업 부하 분석에 NIOSH 들기 공식 적용: 사례연구 (Application of NIOSH Lifting Equation to Analysis of Workload for Patients Transferring by Physical Therapist: a Case Study)

  • 이인희
    • The Journal of Korean Physical Therapy
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    • 제21권3호
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    • pp.119-124
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    • 2009
  • Purpose: The National Institute for Occupational Safety and Health (NIOSH) lifting equation (NLE) is a useful tool to ergonomically analyze a workload. The NLE has high reliability and it can assess tasks by analyzing the work process. The purpose of this case study was to try using the NLE to analyze the workload of transferring patients by physical therapists in the hospital setting. Methods: We observed a physical therapist (PT) transferring patients from a wheelchair to a tilt table and a therapeutic table in one day. Two types of patient transferring methods were evaluated; (1) the manual single person method of stand, pivot and transfer, and (2) manual two person lifting under the thigh and grasping the waist for totally dependent patients. Results: The NIOSH lifting indexes of a person grasping the waist during the manual two person lifting were 5.52~4.48 according to the patient's weight. The NIOSH lifting indexes were 3.34 and 4.48 for the tasks performed by the manual single person method. Conclusion: Because transferring patients is not done very frequently, patients transferring tasks by a PT are not included as one of the musculoskeletal disorder related risky work criteria of the Korea Ministry of Labor. But the NIOSH lifting indexes of a person grasping the waist during the manual two person lifting and the manual single person method were over the NIOSH recommended weight limit threshold.

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금융시장 전염 동적 검정 (Dynamic analysis of financial market contagion)

  • 이희수;김태윤
    • 응용통계연구
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    • 제29권1호
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    • pp.75-83
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    • 2016
  • 본 연구에서는 금융시장 통합화에 따른 금융 시장 전염을 생물학적 전염개념에 기초하여 분석하는 검정 방법론을 제시하였다. 금융 시장 통합화를 측정하기 위하여 U-통계량을 사용하였고, 금융 시장 전염 검정을 위하여 단일방정식 오차수정 모형을 중심으로 잠재 요인모형, 분위수 회귀모형과 런검정을 사용하였다. 시뮬레이션결과 단일방정식 오차수정 모형이 자기상관을 갖는 오차항을 포함한 선형 회귀모형에서 비교적 높은 수준의 적합도를 일관성 있게 보여 주고 있다.

Estimation Model and Vertical Distribution of Leaf Biomass in Pinus sylvestris var. mongolica Plantations

  • Liu, Zhaogang;Jin, Guangze;Kim, Ji Hong
    • 한국산림과학회지
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    • 제98권5호
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    • pp.576-583
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    • 2009
  • Based on the stem analysis and biomass measurement of 36 trees and 1,576 branches in Pinus sylvestris var. mongolica (Mongolian pine) plantations of Northeast China, this study was conducted to develop estimation model equation for leaf biomass of a single tree and branch, to examine the vertical distribution of leaf biomass in the crown, and to evaluate the proportional ratios of biomass by tree parts, stem, branch, and leaf. The results indicated that DBH and crown length were quite appropriate to estimate leaf biomass. The biomass of single branch was highly correlated with branch collar diameter and relative height of branch in the crown, but not much with stand density, site quality, and tree height. Weibull distribution function would have been appropriate to express vertical distribution of leaf biomass. The shape parameters from 29 sample trees out of 36 were less than 3.6, indicating that vertical distribution of leaf biomass in the crown was displayed by bell-shaped curve, a little inclined toward positive side. Apparent correlationship was obtained between leaf biomass and branch biomass having resulted in linear function equation. The stem biomass occupied around 80% and branch and leaf made up about 20% of total biomass in a single tree. As the level of tree class was increased from class I to class V, the proportion of the stem biomass to total biomass was gradually increased, but that of branch and leaf became decreased.

단일 이종접합 구조에서의 2차원 전자개스(2DEG)의 수치적 연산을 위한 양자역학적 분석 (Quantum Mechanical Analysis for the Numerical Calculation of Two-Diemensional Electron Gas(2DEG) in Single-Heterojunction Structures)

  • 황광철;김진욱;원창섭;안형근;한득영
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제49권10호
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    • pp.564-569
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    • 2000
  • This paper analyzed single AlGaAs/GaAa heterojunction energy band structures by solving Schr dinger's equation and Poisson's equation self-consistently. Four different concentrations, positively ionized donors, holes in the valence band, free electrons in the conduction band and 2DEG are taken into account for the whole system. 2DEG from both of the structures are obtained and compared with the date available in the literatures. Differential capacitances are also calculated from the concentration profiles obtained to prove the validity of the single AlGaAs/GaAs system. Finally, theoretical predictions for both of 2DEGs and the capacitances show good agreement with the experimental data referred in this study. It has only an error of les than 10 percent.

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OSCILLATION AND ASYMPTOTIC BEHAVIOR FOR DELAY DIFFERENTIAL EQUATIONS

  • Choi, Sung-Kyu;Koo, Nam-Jip;Ryu, Hyun-Sook
    • Journal of applied mathematics & informatics
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    • 제7권2호
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    • pp.641-652
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    • 2000
  • In this paper we will survey the recent results about oscillation and asymptotic behavior for the linear differential equation with a single delay x'9t)+p(t)x(t-r)=0, $t\geqt_1$.

난류조건에서의 점착성 유사 이군집 응집 모형 적용성 평가 (Evaluation of the Two Class Population Balance Equation for Predicting the Bimodal Flocculation of Cohesive Sediments in Turbulent Flow)

  • 이병준
    • 한국수자원학회논문집
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    • 제48권3호
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    • pp.233-243
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    • 2015
  • 이군집 응집현상은 수자원환경에서 점착성 유사가 결합-해체의 과정을 통해 응집핵-응집체의 이군집 입자크기분포 (Biomodal Floc Size Distribution)를 형성하는 일련의 과정을 의미한다. 본 연구는 저난류 및 고난류 두 가지 조건에서 수행한 응집-침전관 실험결과를 바탕으로 이군집 응집모형(TCPBE: Two Class Population Balance Equation)의 적용성을 단일군집 응집모형(SCPBE: Single Class Population Balance Equation) 및 다군집 응집모형(MCPBE: Multi Class Population Balance Equation)과 비교 평가하였다. 기존 SCPBE에 비하여, TCPBE는 응집핵-응집체의 상호작용 및 침강속도차에 따른 응집 기작을 모의할 수 있었다. 또한, 3개의 연립미분방정식을 가진 TCPBE는 30개 미분방정식을 가진 다군집 응집모형(MCPBE: Multi Class Population Balance Equation)과 대등한 모의 결과를 나타내었다. 따라서 TCPBE는 이군집 응집현상을 모의 할 수 있는 가장 단순한 모델로 검증되었고, 향후 수자원환경이나 수처리 공정에 다양하게 적용할 수 있으리라 판단된다.

제조담배의 연기희석에 미치는 재료품과 궐련 물성 연구 I. 제조담배의 연기희석율과 팁 흡인저항에 미치는 팁페이파 및 필터권지 기공도의 영향 (Study on cigarette ventilation with cigarette materials and the properties of cigarettes 1. Effect of tipping paper permeability and plugwrap porosity on the cigarette pressure drop and ventilation)

  • 김성한;오영일;이영택;박태무
    • 한국연초학회지
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    • 제10권1호
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    • pp.83-91
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    • 1988
  • The effects of tipping paper permeability and plugwrap porosity on the ventilation and the pressure drop of cigarettes have been studied and the results obtained were as follows. 1. The single and the multiple regression equation to estimate tip ventilation were establised. In the equations, the observed values of the tip ventilation with the varieties the plugwrap porosity were content with them by the single regression equation. 2. As based on the statistical consideration of the above equation, the deviation of the observed tip ventilation versus the tipping paper permeability were higher than them to the plugwrap porosity. 3. The regression equations to calculate pressure drop ratio and the total ventilation rate in filter tip from the tea ventilation were obtained. According to the equation, the observed values of the pressure drop ratio were significantly similar to them calculated. 4. It was found that the equations could be applied to the calculation of the ventilation of cigarettes using the mechanical and micro laser perforation tipping paper as well as the electrically perforated tipping paper of this Study.

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A PARAMETRIC SCHEME FOR THE NUMERICAL SOLUTION OF THE BOUSSINESQ EQUATION

  • Bratsos, A.G.
    • Journal of applied mathematics & informatics
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    • 제8권1호
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    • pp.45-57
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    • 2001
  • A parametric scheme is proposed for the numerical solution of the nonlinear Boussinesq equation. The numerical method is developed by approximating the time and the space partical derivatives by finite-difference re placements and the nonlinear term by an appropriate linearized scheme. The resulting finite-difference method is analyzed for local truncation error and stability. The results of a number of numerical experiments are given for both the single and the double-soliton wave. AMS Mathematics Subject Classification : 65J15, 47H17, 49D15.

STABILITY OF THE MULTI-JENSEN EQUATION

  • Prager, Wolfgang;Schwaiger, Jens
    • 대한수학회보
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    • 제45권1호
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    • pp.133-142
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    • 2008
  • Given an $m{\in}\mathbb{N}$ and two vector spaces V and W, a function f : $V^m{\rightarrow}W$ is called multi-Jensen if it satisfies Jensen's equation in each variable separately. In this paper we unify these m Jensen equations to obtain a single functional equation for f and prove its stability in the sense of Hyers-Ulam, using the so-called direct method.

A PREDICTOR-CORRECTOR SCHEME FOR THE NUMERICAL SOLUTION OF THE BOUSSINESQ EQUATION

  • Ismail, M.S.;Bratsos, A.G.
    • Journal of applied mathematics & informatics
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    • 제13권1_2호
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    • pp.11-27
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    • 2003
  • A fourth order in time and second order in space scheme using a finite-difference method is developed for the non-linear Boussinesq equation. For the solution of the resulting non-linear system a predictor-corrector pair is proposed. The method is analyzed for local truncation error and stability. The results of a number of numerical experiments for both the single and the double-soliton waves are given.