• 제목/요약/키워드: Relaxation Method

검색결과 960건 처리시간 0.024초

3차원 비길로틴 자재절단문제의 라그랑지안 완화 해법 (A Lagrangean Relaxation Method of Three-Dimensional Nonguillotine Cutting-Stock Problem)

  • 김상열;박순달
    • 대한산업공학회지
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    • 제22권4호
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    • pp.741-751
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    • 1996
  • The three dimensional cutting-stock problem is to maximize the total value of pieces which are smaller cubics-cut from a original cubic stock. This paper suggests a method to maximize the total value of different size cut pieces using the orthogonal non-guillotine cut technique. We first formulated a zero-one integer programming, then developed a Lagrangeon relaxation method far the problem. The solutions were given by using a brunch-end-bound technique associates with Lagrangean relaxation, which guarantees an optimal solution.

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The dynamic relaxation method using new formulation for fictitious mass and damping

  • Rezaiee-Pajand, M.;Alamatian, J.
    • Structural Engineering and Mechanics
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    • 제34권1호
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    • pp.109-133
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    • 2010
  • This paper addresses the modified Dynamic Relaxation algorithm, called mdDR by minimizing displacement error between two successive iterations. In the mdDR method, new relationships for fictitious mass and damping are presented. The results obtained from linear and nonlinear structural analysis, either by finite element or finite difference techniques; demonstrate the potential ability of the proposed scheme compared to the conventional DR algorithm. It is shown that the mdDR improves the convergence rate of Dynamic Relaxation method without any additional calculations, so that, the cost and computational time are decreased. Simplicity, high efficiency and automatic operations are the main merits of the proposed technique.

사무직 근로자에 대한 운동요법과 이완요법이 스트레스 반응으로 카테콜라민과 심박수에 미치는 영향 (Streets of Relaxation Therapy and Exercise Therapy on Catecholamine and Heart Rate Response for Job Stress of White Color Workers)

  • 김인흥
    • 기본간호학회지
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    • 제6권2호
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    • pp.240-254
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    • 1999
  • The purpose of this study was to investigate the effect of exercise therapy and relaxation therapy on catecholamine and heart rate in people in white color jobs and to determine this information the effectiveness of applied exercise therapy and relaxation therapy as a nursing intervention method for stress patients. The subjects were divided into an exercise therapy group, a relaxation therapy group, and control group and the research design was a nonequivalent control group pretest-post test design(exercise therapy : n= 12, relaxation therapy : n=12, control group, the group without any treatment in exercise on relaxation therapy : n=12), The subjects in the exercise therapy group were given a particular intensity for each kp during 30min, bicycle ergometer which is using an LX PE training system before & after 4weeks of training. The exercise therapy that was used was Astrard load method which tested absolute exercise load of heart rate before & after four weeks, and resting heart rate was tested for exercise and relaxation therapy before, after four weeks, and at eight weeks. The results of each kp & absolute exercise load were calculated with the target rate formula(maximal heart rate-rest heart rate) x exercise intensity(%) + rest heart rate so the subjects could continue 60-70% exercise intensity for exercise therapy over eight weeks. The relaxation therapy subjects were trained using a modified Jacobson's relaxation technique for eight weeks. The exercise and relaxation therapy were trained at the following intensity for eight weeks(3times/week, 30min/day) to see changes in catecholamine & heart rates. After eight weeks, statistical analysis of exercise & relaxation therapy were carried out Two-way ANOVA and multiple range test(SNK : Student Newman Keul) were used. The results are as follows : 1. The change of epinephrine & norepinephrine in the exercise therapy, relaxation therapy, and control group was statistically significant at the .05 level after four weeks & eight weeks. Also, exercise therapy was statistically significant at .05 level over that of the control group after 4weeks. 2. The change of heart rate in relaxation therapy was statistically significant at the .05 level, and was statistically significant at the .05 level over that of the exercise therapy and control group. In conclusion, it is obvious that exercise therapy and relaxation therapy should be one of the most effective stress treatment and desirable nursing interventions methods for job stress in people in white color jobs.

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ACCELERATION OF ONE-PARAMETER RELAXATION METHODS FOR SINGULAR SADDLE POINT PROBLEMS

  • Yun, Jae Heon
    • 대한수학회지
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    • 제53권3호
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    • pp.691-707
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    • 2016
  • In this paper, we first introduce two one-parameter relaxation (OPR) iterative methods for solving singular saddle point problems whose semi-convergence rate can be accelerated by using scaled preconditioners. Next we present formulas for finding their optimal parameters which yield the best semi-convergence rate. Lastly, numerical experiments are provided to examine the efficiency of the OPR methods with scaled preconditioners by comparing their performance with the parameterized Uzawa method with optimal parameters.

Numerical Solution of Nonlinear Diffusion in One Dimensional Porous Medium Using Hybrid SOR Method

  • Jackel Vui Lung, Chew;Elayaraja, Aruchunan;Andang, Sunarto;Jumat, Sulaiman
    • Kyungpook Mathematical Journal
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    • 제62권4호
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    • pp.699-713
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    • 2022
  • This paper proposes a hybrid successive over-relaxation iterative method for the numerical solution of a nonlinear diffusion in a one-dimensional porous medium. The considered mathematical model is discretized using a computational complexity reduction scheme called half-sweep finite differences. The local truncation error and the analysis of the stability of the scheme are discussed. The proposed iterative method, which uses explicit group technique and modified successive over-relaxation, is formulated systematically. This method improves the efficiency of obtaining the solution in terms of total iterations and program elapsed time. The accuracy of the proposed method, which is measured using the magnitude of absolute errors, is promising. Numerical convergence tests of the proposed method are also provided. Some numerical experiments are delivered using initial-boundary value problems to show the superiority of the proposed method against some existing numerical methods.

동적이완법을 이용한 후좌굴 해석법의 Hybrid 구조물의 적용성 평가 (A Study on the Post-Buckling Analysis of Spatial Structures Using Dynamic Relaxation Method)

  • 이경수;이상주;한상을
    • 한국공간구조학회:학술대회논문집
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    • 한국공간구조학회 2006년도 춘계 학술발표회 논문집 제3권1호(통권3호)
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    • pp.58-65
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    • 2006
  • 대공간 구조 시스템의 대변형 거동 산정법으로 최근 동적이완법의 적용에 대한 연구가 진행되고 있다. 동적이완법에서는 접선 강성 매트릭스의 수식 계산이 필요하지 않고, 단지 벡터량을 이용함으로써 해로 수렴하며, 전체 계산 과정에서 강성 매트릭스는 필요하지 않다. 동적이완법의 이점을 평가하기 위해 많은 대공간 구조 시스템에 대해 적용하였고, 이는 대공간 구조 시스템의 후좌굴 거동을 추적하는데 있어서 동적이완법 사용의 타당성을 규명할 수 있다.

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유한요소법을 이용한 지반 공동 및 이완영역 모사에 관한 연구 (A Study on Simulation of Cavity and Relaxation Zone Using Finite Element Method)

  • 유승경;김주봉;한중근;홍기권;윤중만;이강일
    • 한국지반신소재학회논문집
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    • 제16권4호
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    • pp.67-74
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    • 2017
  • 지반 공동 발생으로 인한 지반함몰 사고를 미연에 방지하기 위해서는 발생된 공동 주변 지반의 이완영역에 대한 역학적 특성 평가와 더불어 이에 상응하는 적합한 보강 대책을 신속히 수립하는 것이 필요하다. 본 논문에서는 지중 공동 주변의 이완영역 발생에 대한 메커니즘 분석을 위해 유한요소 수치해석을 실시하였다. 수치해석에서는 지중 공동과 이완영역을 모사하기 위해 강제변위법을 적용하였으며, 수치해석 결과는 실내모형실험을 수행한 기존 연구 결과를 이용하여 검증하였다. 유한요소 수치해석 결과로부터 토사 유실로 인한 공동 주변 지반의 간극비 분포 특성을 파악하였으며, 전단응력 감소 특성을 분석하여 이완영역의 범위를 정량적으로 제시하였다.

한국인의 이완(Relaxation) 개념에 관한 연구 (A Study on Koream Concepts of Relaxation)

  • 박정숙
    • 대한간호
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    • 제31권2호
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    • pp.70-85
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    • 1992
  • Relaxation technique is an independent nursing intervention used in various stressful situations. The concept of relaxation must be explored for the meaning given by the people in their traditional thought and philosophy. Korean relaxation technique, wanting to become culturally acceptable and effective, is learning to recognize and develop Korean concepts, experiences, and musics of relaxation. This study was aimed at discovering Korean concepts, experiences and musics of relaxation and contributing the development of the relaxation technique for Korean people. The subjects were 59 mursing students, 39 hospitalized patients, 61 housewives, 21 rural residents and 16 researchers. Data were collected from September 4th to October 24th, 1991 by interviews or questionaires. The data analysis was done by qualitative research method, and validity assured by conformation of the concept and category by 2nursing scientists who had written a Master's thesis on the relaxation technique. The results of the study were summerized as follows; 1. The meaning of the relaxation concept; From 298 statements, 107 concepts were extracted and then 5 categories "Physical domain", "Psychological domain", "Complex domain", "Situation", and "environment" were organized. 'Don't have discomforts, 'don't have muscle tension', 'don't have energy(him in Korean)', 'don't have activities' subcategories were included in "Physical domain". 'Don't have anxiey', 'feel good', 'emotional stability', 'don't have wordly thoughts', 'feel one's brain muddled', 'loss of desire' subcategories were included in "physical domain" 'Comfort body and mind', 'don't have tension of body and mind', 'be sagged' 'liveliness of thoughts' subcategories were included in "Complex domain". 'Rest', 'sleep', 'others' subcategories were included in "Situation domain". And 'quite environment' & 'comfortable environment' subcategories were included in "Environmental domain". 2. The experiences of the relaxation; From 151 statements, 59 experiences were extracted. And then 9 categories-at rest after physical activities, after problem solving, fancy, bathing in the bed, situation, rest, particular time, others-were organized. 3. The musics of the relaxation; From 229 statements, 108 musics were extracted. and the 9 categories- Western classical music, semi classical music, Korean song, Korean popular classical music, song, western popular sonhg, hymn, characteristics of music, others - were organized. In conclusion, There are some differences between Korean concepts, experiences and musics of relasation and western concepts, experiences and musics of relaxation.

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압력 파형을 이용한 좌심실 확장 이완율의 실시간 추정 (Real Time Estimation of the Left Ventricular Diastolic Relaxation Rate using Intraventricular Pressure Waveform)

  • 천홍구;김희찬;손대원
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1997년도 추계학술대회
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    • pp.415-419
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    • 1997
  • The left ventricular relaxation rate is used as a golden standard which describes the left ventricular diastolic unction. So far, to get the rate of relaxation one should calculate the data after full recording, that is, off-line method. Therefore one cannot get the rate of relaxation in real-time while changing loading condition or infusing drug. But real time monitoring of the relaxation rate is necessary while changing loading condition or infusing drug to control the mechanics of heart and to get more information. We propose a new criterion to get the left ventricular relaxation rate and a real time algorithm. By comparison, it was turned out that our criterion outperforms others criterion.

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초단파 레이저 조사시 티슈 열완화 시간 분석 (Analysis of Thermal Relaxation Time of Tissues Subject to Pulsed Laser Irradiation)

  • 김경한;이제훈;서정
    • 한국레이저가공학회지
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    • 제12권2호
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    • pp.17-25
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    • 2009
  • Two methodologies for predicting thermal relaxation time of tissue subjected to pulsed laser irradiation is introduced by the calculation the optical penetration depth and by the investigation of the temperature diffusion behavior. First approach is that both x-axial and y-axial thermal relaxation times are predicted and they are superposed to achieve the thermal relaxation time (${\tau}_1$) for two-dimensional square tissue model. Another approach to achieve thermal relaxation time (${\tau}_2$) is measuring the time required for local temperature drop until $e^{-1}$ of the maximum laser induced heating.

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