• 제목/요약/키워드: compliance characteristics

검색결과 470건 처리시간 0.029초

유전 알고리듬을 이용한 토션빔 현가장치의 기구학적 최적설계 (Kinematic Optimum Design of a Torsion-Beam Suspension Using Genetic Algorithms)

  • 옥진규;백운경;손정현
    • 한국자동차공학회논문집
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    • 제14권1호
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    • pp.25-30
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    • 2006
  • This study is about an optimum design to improve the kinematic and compliance characteristics of a torsion-beam suspension system. The kinematic and compliance characteristics of an initial design of the suspension was obtained through a roll-mode analysis. The objective function was set to minimize within design constraints. The coordinates of the connecting point between the torsion-beam and the trailing arm were treated as design parameters. Since the torsion-beam suspension has large nonlinear effects due to kinematic and elastic motion, Genetic Algorithms were employed for the optimal design. The optimized results were verified through a double-lane change simulation using the full vehicle model.

유한요소법과 가진시험법을 이용한 다기능 5축 복합가공기의 동특성 해석 및 동적 컴플라이언스 평가에 관한 연구 (A Study on Analysis of Dynamic Characteristics and Evaluation of Dynamic Compliance of a 5-Axis Multi-tasking Machine Tool by Using F.E.M and Exciter Test)

  • 장성현;최영휴;하종식
    • 한국공작기계학회논문집
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    • 제18권2호
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    • pp.162-169
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    • 2009
  • This paper describes a study on dynamic characteristics analysis and dynamic compliance evaluation of a 5-axis multi-tasking machine tool of ram-head type. Structural dynamics analysis and evaluation are necessary to machine tool design and development to secure good machine tool performance against tough and harsh machining conditions. In this study, natural frequencies and corresponding vibration modes of the machine tool structure were analyzed by using both F.E.M. modal analysis and impulse hammer test. Furthermore, dynamic compliance of the machine tool was analyzed by using F.E.M. and also measured by using a hydraulic exciter test. Both the theoretical analysis and experimental test results showed good agreement with each other.

준-순간 하중에 의한 초기재령 콘크리트의 순간 및 크리프 컴플라이언스 함수 (Instantaneous Compliance and Creep Compliance functions of Early-Age Concrete under Quasi-Instantaneous Loading)

  • 오병환;최성철;박호
    • 콘크리트학회논문집
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    • 제17권1호
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    • pp.11-18
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    • 2005
  • 온도 및 수분의 변화로 인하여 초기재령 콘크리트에서 발생하는 응력을 합리적으로 예측하기 위해서는 초기재령 콘크리트의 경화특성을 실제적으로 표현할 수 있는 컴플라이언스 함수가 필요하다. 그러나, 기존의 컴플라이언스 함수는 경화된 콘크리트의 데이터로부터 도출되어 초기재령 콘크리트의 특성을 합리적으로 표현하지 있지 않다. 또한 탄성 컴플라이언스를 측정하는 기존의 실험에서는 하중도달시간이 존재하므로 탄성 컴플라이언스와 크리프 컴플라이언스의 구분이 모호해지며 탄성 컴플라이언스에 크리프의 영향이 존재하는 문제점이 있다. 본 연구에서는 먼저 순간 컴플라이언스 함수를 실제적으로 추정할 수 있는 실험적 방법론을 제시하였다. 제시된 실험적 방법론을 이용하여 다양한 하중도달시간과 재령에 대하여 준-순간 컴플라이언스를 실험적으로 측정하여 순간 컴플라이언스를 제시하였다. 또한 초기재령 콘크리트에 대하여 크리프 실험을 수행하였다. 이로부터 고체화 이론에 기초하여 콘크리트의 컴플라이언 함수를 표현하는 B3 모델을 초기재령 콘크리트에 합리적으로 적용될 수 있도록 수정하여 제시하였다. 따라서 본 연구에서 제안된 컴플라이언스 함수는 초기재령 콘크리트의 시간에 따른 응력을 합리적으로 평가하는데 유용하게 활용될 수 있을 것으로 사료된다.

SA508-3재의 제하컴플라이언스법과 하중비해석을 이용한 파괴저항곡선 평가 (J-R Curve Characterization by Load Ratio Analysis and Unloading Compliance Method for SA508 C-3 steel)

  • 임만배;차귀준;윤한기;안원기
    • 한국해양공학회지
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    • 제12권1호
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    • pp.65-75
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    • 1998
  • The fracture resistance curve is one of most important and design techniques employed in nuclear pressure vessel structures. This study is to evaluate the J-R curve characteristics for the SA508C-3 by the unloading compliance method and load rato analysis. The effect of strain aging for the exponential correlation of the J-R curve in this metal are investigated at room temperature, 20$0^{\circ}C$ and 30$0^{\circ}C$. The load ratio analysis method can evaluate the J-R curve by using the simple tension load-displacement curve only without the repeat of the unloading and loading. Therefore, the analysis by the proposed load ratio method has a merit, in comparison with the unloading compliance method, which can measure the crack length without the precision measurement equipment.

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초음파 모터를 사용한 DD 매니퓰레이터의 컴플라이언스 제어 (Compliance Control of DD Manipulator using Ultrasonic Motor)

  • 김동옥;신덕;김원배;성도생;김영동
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1996년도 창립기념 전력전자학술발표회 논문집
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    • pp.47-51
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    • 1996
  • In this paper, we propose a method for compliance control of a SCARA type 2-freedom direct drive(DD) manipulator. Each joint of the manipulator is driven by a travelling ultrasonic motor(USM). The travelling USM has good some characteristics over conventional servo motors such as compact size, light weight, silent motion, high torque and high speed response. By controlling the elasticity and viscosity of robot joints, a robot can work in compliance with external environment. we control the elastic coefficient and the viscous coefficient of joint by adjusting the phase difference of the motor power. And we contemplate transient response of USM with adjusting the elastic coefficient and the viscous coefficient. To use the result, we can control the robot to reach its goal with compliance motion. It remains for further research to develop the impedance control of USM.

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Sub-modeling을 이용한 end-to-end 문합의 비선형 해석 (Nonlinear Analysis of End-to-End Anastomosis Using Sub-modeling)

  • 한근조;안성찬;심재준
    • 한국정밀공학회지
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    • 제20권2호
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    • pp.192-198
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    • 2003
  • A finite element analysis of end-to-end artery/PTFE anastomosis has been presented in this study to evaluate the distribution of compliance and stresses in the vicinity of the anastomosis due to any mismatch in compliance characteristics. The artery wall was assumed to be made of linear isotropic material in this simplified model and a nonlinear analysis and convergency study with respect to increasing meshed element numbers were performed with a mean artery pressure loading of the artery-PTFE model. Also, sub-modeling method was Introduced to progress the accuracy of the finite element analysis. The results are as follow : 1. A hypercompliant zone on the artery side was observed around 4.Omm from the anastomosis and a high hoop stresses in the wall of artery and PTFE was dominant. 2. An artery displays large deformation so that nonlinear analysis and sub-modeling method was used. 3. An anastomosis with the thinner thickness and larger diameter PTFE (B type) could reduce the compliance disagreement.

일부 대학생이 지각한 신종인플루엔자 A (H1N1)의 지식, 태도 및 예방행위 실천도와의 관계 (Perceived Knowledge, Attitude, and Compliance with Preventive Behavior on Influenza A (H1N1) by University Students)

  • 최정실;양남영
    • 성인간호학회지
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    • 제22권3호
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    • pp.250-259
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    • 2010
  • Purpose: This study was examined to identify the relationship among knowledge, attitude, and compliance with preventive behavior on influenza A (H1N1) by University students. Methods: The sample consisted of 101 students. The data were collected from August to September 2009 and analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and stepwise multiple regression. Results: The mean scores of knowledge ($11.89{\pm}1.39$), attitude ($30.16{\pm}2.87$), and compliance with preventive behavior ($22.35{\pm}3.51$) on influenza A (H1N1) were above the average. The level of knowledge was not significantly different regardless of characteristics. Students' attitude differed according to gender (p<.001), and plan to seasonal influenza vaccination for this year (p=.007). Compliance with preventive behavior was significantly different according to experience of seasonal influenza vaccination during last year (p=.010), experience of obtained information about influenza A (H1N1) (p=.037). Significant correlations were found between knowledge and compliance with preventive behavior (p<.001), attitude and compliance with preventive behavior (p<.001). Knowledge and attitude was a predictor of compliance with preventive behavior (23.4%). Conclusion : These findings indicate that perceived knowledge and attitude may be necessary to improve compliance with preventive behavior on influenza A (H1N1) among university students. The results of the study can be utilized in educational programs about preventing the occurrence of influenza among university students.

Associations Between Compliance With Non-pharmaceutical Interventions and Social-distancing Policies in Korea During the COVID-19 Pandemic

  • Hwang, Yu Seong;Jo, Heui Sug
    • Journal of Preventive Medicine and Public Health
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    • 제54권4호
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    • pp.230-237
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    • 2021
  • Objectives: This study explored changes in individuals' behavior in response to social distancing (SD) levels and the "no gatherings of more than 5 people" (NGM5) rule in Korea during the coronavirus disease 2019 (COVID-19) pandemic. Methods: Using survey data from the COVID-19 Behavior Tracker, exploratory factor analysis extracted 3 preventive factors: maintenance of personal hygiene, avoiding going out, and avoiding meeting people. Each factor was used as a dependent variable. The chisquare test was used to compare differences in distributions between categorical variables, while binary logistic regression was performed to identify factors associated with high compliance with measures to prevent transmission. Results: In men, all 3 factors were significantly associated with lower compliance. Younger age groups were associated with lower compliance with maintenance of personal hygiene and avoiding meeting people. Employment status was significantly associated with avoiding going out and avoiding meeting people. Residence in the capital area was significantly associated with higher compliance with personal hygiene and avoiding venturing out. Increasing SD levels were associated with personal hygiene, avoiding going out, and avoiding meeting people. The NGM5 policy was not significantly associated with compliance. Conclusions: SD levels, gender, age, employment status, and region had explanatory power for compliance with non-pharmaceutical interventions (NPIs). Strengthening social campaigns to inspire voluntary compliance with NPIs, especially focused on men, younger people, full-time workers, and residents of the capital area is recommended. Simultaneously, efforts need to be made to segment SD measures into substrategies with detailed guidance at each level.

당뇨병 환자의 당뇨병 조절과 식사요법 실천 관련요인과의 상관성 (Interrelationship between Diabetic Control and Related Factors of Dietary Compliance in Diabetic Patients)

  • 최지은;서정숙
    • 대한영양사협회학술지
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    • 제11권2호
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    • pp.137-146
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    • 2005
  • This study was carried out to investigate the relationship between diabetic control and related factors of the practice of diet therapy which affects mostly diabetic patients’ dietary compliance. A questionnaire survey was conducted on 128 diabetic patients who had visited Internal medicine endocrinology clinic at University Medical Center of Daegu area. The questionnaires including clinical characteristics, meal regularity and food intake which shows dietary compliance, intrinsic barriers to the practice of diet therapy and knowledge of diet therapy were asked and analyzed. The factor which affects HbA1c was intrinsic barriers and HbA1c became higher as the level of intrinsic barriers was increasing. The education on diet therapy had no influence on the intrinsic barriers, but the level of knowledge on diet therapy was shown higher in the educated patients. The above results suggest that the practice of diet therapy should be leaded to develop behavioral aspects through resonable motivation on dietary compliance along with removing intrinsic barriers rather than simply providing information.

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노인 고혈압 환자의 저염식이 이행, 나트륨 섭취 및 짠 맛에 대한 기호도 (Compliance with a Low-Salt Diet, Sodium Intake, and Preferred Salty Taste in the Hypertensive Elderly)

  • 이영희;김현경;권경희
    • 한국보건간호학회지
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    • 제24권2호
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    • pp.311-322
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    • 2010
  • Purpose: This study aimed to examine the compliance to a low-salt diet, sodium intake, and preferred salty taste in elderly patients with hypertension. Methods: A cross-sectional descriptive design was used. Participants were 105 elderly patients with hypertension living in a rural area. The compliance with a low-salt diet, sodium intake, and preferred salty taste, blood pressure, body mass index, and waist circumference were measured, and compared according to the general characteristics and the levels of blood pressure. Descriptive statistics, $X^2$-test, t-test, and ANOVA were used for data analysis. Results: compliance with a low-salt diet was marginally elevated. Sodium intake was relatively high and the main sources were seasonings and vegetables. The participants tended to prefer high levels of salt. Sodium intake was significantly higher the hypertensive individuals (stage I and II) compared to prehypertensive subjects on a normal maintenance diet. Sodium intake from vegetables was also significantly different between the two groups. Conclusion: Nursing intervention for hypertensive elderly patients should include strategies to decrease sodium intake.