다수 수요시점을 가진 선박 일정 문제에 관한 연구

기도형,박순달 한국경영과학회 1989 한국경영과학회 학술대회논문집 Vol.- No.1

The ship scheduling problem with multiple demand time points is to determine the optimal ship scheduling under the condition which a demand place has sveral demand time points for a planning horizon. The objective of this thesis is to develope a heuristic algorithm which, given demand place, time points and quantity, minimizes total cost of chartering transportation units. In this thesis, first the problem is transformed into the network form in consideration of time condition. Next, m-longest paths are obtained by PERT/CPM algorithm, then the scheduling is determined by using m-longest paths.

심물리학적 방법을 이용한 여성의 안락 동작범위

기도형,Kee, Do-Hyung 대한인간공학회 2002 大韓人間工學會誌 Vol.21 No.1

This study aims to provide joint angles of comfort for females, based on the psychophysical scaling method. Ten female subjects participated in the experiment for measuring perceived discomfort for varying joint motions. The subjects were instructed to maintain given joint motions for a minute, and to rate their perceived discomfort for the motions during a minute's rest by using the free modulus method of the magnitude estimation. Joint angles of comfort were calculated from the regression equations based on the experimental results, in which levels of joint motions were used as independent variables and perceived discomforts as dependent variables. The results showed that joint angles of comfort for the joint motions investigated were much smaller than full range of motions for corresponding joint motions. The ratios of joint angle of comfort to its range motion for the hip were found to be smallest of all joint motions dealt with in this study, and those for the neck were the largest. In addition, comfortable joint angles for females were much smaller than those for males. It is recommended that when designing or evaluating workplaces ergonomically, different comfortable joint angles should be applied according to workers' or population's gender.

어깨 및 팔 동작 부하 측정을 위한 관찰적 기법 비교

기도형 대한안전경영과학회 2024 대한안전경영과학회지 Vol.26 No.2

This study aims to compare six observational methods for assessing arm- and hand-intensive tasks, based on literature review. The comparison was conducted in viewpoints of body regions, force/external load, motion repetition, other factors including static posture, coupling, duration/break, pace, temperature, precision task, and final risk or exposure level. The number of risk factors assessed was more, and assessment procedure was more complex than the observational methods for assessing whole-body postural loads such as Ovako Working Posture Analysis System(OWAS), Rapid Upper Limb Assessment(RULA), and Rapid Entire Body Assessment(REBA). Due to these, the intra- and inter-reliabilities were not high. A past study showed that while Hand Arm Risk Assessment Method(HARM) identified the smallest proportion of the work tasks as high risk, Strain Index(SI) and Quick Exposure Check(QEC) hand/wrist were the most rigorous with classifying most work tasks as high risk. This study showed that depending on the observational technique compared, the evaluation factors, risk or exposure level, and evaluation results were different, making it necessary to select a technique appropriate for the characteristics of the work being assessed.

심물리학적 방법을 이용한 정적 관절 동작에 대한 여성의 지각 불편도

기도형 대한산업공학회 2003 산업공학 Vol.16 No.1

외부 부하와 반복에 따른 팔 동작의 심물리학적 자세 부하

기도형 대한산업공학회 2004 산업공학 Vol.17 No.2

손목 동작의 반복과 외부 부하에 따른 심물리학적 부하

기도형 한국안전학회 2004 한국안전학회지 Vol.19 No.4

This study investigated effect of arm posture, repetition of wrist motion and external load on perceived discomfort. The arm postures were controlled by shoulder flexion, elbow flexion, and wrist motions such as flexion, extension, radial deviation and ulnar deviation. An experiment was conducted to measure discomfort scores for experimental treatments using the magnitude estimation, in which the L16 orthogonal array was adopted for reducing the size of experiment. The results showed that while the effect of the shoulder flexion, repetition of wrist motion and external load was statistically significant at α = 0.05 or 0.10, that of the elbow and wrist motions was not. Discomfort ratings increased linearly as levels of wrist repetition and external load increased. This implies that the existing posture classification schemes such as OWAS, RULA, which do not properly consider effect of motion repetition and external load, may underestimate postural load. Based on the regression equation for wrist repetition and external load, isocomfort region indicating the region within which discomfort scores were expected to be the same was proposed. It is recommended that when assessing risk of postures or developing new posture classification schemes, motion repetition and external load as well as posture itself be fully taken into consideration for precisely evaluating postural stress.

작업 자세 부하 평가를 위한 자세 분류 체계의 연구 현황 : 관측법을 중심으로 Focused on the Observational Methods

기도형 한국산업안전학회 2000 한국안전학회지 Vol.15 No.4

This study aims to review and assess the existing postural classification schemes used for evaluating postural loads in industry. The schemes can be classified into three categories: self-report, observational and instrument-based techniques depending upon how to record working postures. Of the three techniques, this study was mainly focused on the observational methods. The observational technique is most widely used in the industrial sites because it does not interfere with work, and is easy and simple to use and cost-effective without requiring the use of expensive equipment for estimating the angular deviation of a body segment from the neutral position. In spite of the usefulness and applicability, the techniques have some problems: 1) The existing observational techniques lack the consistency in the class limits of the motion categories in each body segment; 2) Most of them do not provide the post-analysis criteria needed to judge whether or not any posture is acceptable in view point of the postural load; and 3) They can not precisely evaluate the postural load for a given posture because the external loads and dynamic factors including acceleration, moment and force were not taken into consideration.

작업영역의 해석적 생성을 위한 2자유도 동작의 동작범위 측정

기도형 대한인간공학회 1996 大韓人間工學會誌 Vol.15 No.2

To generate workspace analytically using the robot kinematics, data on range of human joints motion, especially range of two degrees of freedom motion, are needed. However, these data have not been investigated up to now. Therefore, in this research, we are to investigate an interaction effect of motions with two degrees of freedom occurred simultaneously at the shoulder, virtual hip(L5/S1) and hip joints, respectively, for 47 young male students. When motion with two degrees of freedom occurred at a joint such as shoulder, virtual hip and hip joints, it was found from the results of ANOVA that the action of a degree of freedom motion may either decrease or increase the effective functioning of the other degree of freedom motion. In other words, the shoulder flexion was decreased as the shoulder was adducted or abducted to $60^{\circ}C$or abducted from $60^{\circ}C$to maximum degree of abduction, while the shoulder flexion increased as the joint was abducted from $60^{\circ}C$ to $60^{\circ}C$ The flexion was decreased as the virtual hip was bent laterally at the virtual hip joint, and also did as the hip was adducted or abducted from the neutral position. It is expected that workspace can be generated more precisely based the data on the range of two degrees of joint motion measured in this study.

Magnitude estimation을 이용한 앉은 자세에서의 인체관절의 불편도측정

기도형,신승헌,김형수 대한산업공학회 1997 대한산업공학회 춘계학술대회논문집 Vol.1997 No.4

유럽연합, 영국 및 미국의 주방 기기 안전 기준 관련 법령 및 규격 조사

기도형,황상돈,송영웅,박현근,Kee, Do-Hyung,Hwang, Sang-Don,Song, Young-Woong,Park, Hyun-Geun 대한안전경영과학회 2017 대한안전경영과학회지 Vol.19 No.2

The purpose of this study is to investigate EU, UK and USA's laws and standards related to safety criteria for commercial kitchen machines. The study was based on literature survey and web surfing. The results revealed that EU has relevant directives by kitchen machines and harmonized standards according to the directives. The directives and harmonized standards are translated into the laws and standards of EU member countries, respectively. The kitchen facility relevant legal systems of UK and USA do not prescribe the safety devices or measures, but only the basic health and safety requirements. The requirements were forcefully implemented through the certificate systems such as CE(Confommite European), UL(Underwriters Laboratories), etc. Only products with CE, UL or NRTL(ationally Recognized Testing Laboratory) certificate marking can be placed on the market of EU and USA, or put into service. For achieving the certificates, all requirements regulated in the relevant standards should be met. The standards of UK and USA were presented by kitchen machines or by standards themselves, respectively. Safety devices required by the standards were also summarized by kitchen machines and their risk factors.