손 힘 사용 측정 FSA 시스템의 성능 평가

정기효,유희천,권오채,Jung, Ki-Hyo,You, Hee-Cheon,Kwon, O-Chae 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.2

The FSA(Force Sensitive Application) system measures hand force by using force resistance sensors. Compared to conventional hand force measurement systems such as Lafayette hand dynamometer and Jamar hydraulic hand dynamometer, the FSA system can be applied to analyze use of hand forces while the hand is manipulating objects for a task, However, the measurement performance of the FSA system has not been objectively evaluated. The present study tested the FSA system in terms of stability, repeatability, accuracy, and linearity. It is shown that the FSA system has good stability (CV$\leq$0.02) and linearity($R^2$=0.82), but has low repeatability(CV=$0.11{\sim}0.19$) and accuracy(22% of underevaluation on average). This performance result indicates that measurements from the FSA system should be used for relative comparison rather than for absolute comparison.

Design Structure Matrix를 활용한 인체측정학적 제품설계 방법: 컴퓨터 워크스테이션 설계 적용

정기효,권오채,유희천,Jung, Ki-Hyo,Kwon, O-Chae,You, Hee-Cheon 대한인간공학회 2007 大韓人間工學會誌 Vol.26 No.3

Design equations for anthropometric product design are developed by considering the geometrical relationships of design dimensions and anthropometric dimensions. The present study applied the design structure matrix (DSM) method to the development of design equations for a computer workstation, and compared design values from the design equations with corresponding design values of ergonomic recommendations and existing products. The relationships between design dimensions (e.g., legroom and worktable) were analyzed by a DSM, and then the application order of design equations (e.g., seatpan, backrest, armrest, legroom, and worktable in descending order) was determined. Next, design equations were developed by analyzing the geometric relationships between computer workstation design dimensions and anthropometric dimensions. Finally, design values for a computer workstation were determined by considering a standard posture defined and representative human models (5th, 50th, 95th %ile). The design values calculated using the design equations were similar with those of ergonomic recommendations found in literature and two commercial products measured in the study; however, some design values (e.g., seatpan height) were different due to discrepancy in standard posture. The DSM method would be utilized to systematically analyze the relationships between design dimensions for anthropometric product design.

인체측정학적 설계를 위한 대표인체모델 생성 기법의 평가: 격자 기법

정기효,유희천,Jung, Ki-Hyo,You, Hee-Cheon 대한인간공학회 2007 大韓人間工學會誌 Vol.26 No.1

Representative human models (RHMs), a group of digital human models which represent the people of the target population within a designated percentage (e.g., 95%), are used for ergonomic design and evaluation in virtual environments. The present study evaluated the grid approach, a RHM generation method, in terms of accommodation percentage. RHMs generated from the grid approach dramatically decreased the accommodation percentage of the target population as the number of anthropometric dimensions under consideration increased. For example, the accommodation percentages by RHMs generated by the grid approach were 95% for 3 key dimensions (selected among 10 anthropometric dimensions), 45% for 5 dimensions, and 10% for 10 dimensions. A standardized multiple regression analysis found that this decreasing accommodation percentage was caused by low correlations between key dimensions and other dimensions. The accommodation evaluation process used in the present study is applicable to evaluation of other RHM generation methods.

기업이미지와 경영성과에 대한 시장지향성의 영향: 중소 이노비즈와 비이노비즈 기업의 조절효과

정기한 ( Ki Han Chung ),정경효 ( Kyeong Hyo Jung ),신재익 ( Jae Ik Shin ) 한국생산성학회 2013 生産性論集 Vol.27 No.1

The purpose of this study is to investigate the relationship among market orientation, company image, and business performance of small manufacturing enterprises in Korea. The results show that information dissemination and information responsiveness of market orientation positively affect company image except information generation. Information dissemination positively affects business performance except information generation and information responsiveness. However, information responsiveness indirectly affects business performance. Company image positively affects business performance. The moderating effects of Inno-Biz firms between market orientation and business performance are not significant. Therefore, it is identified that the role of market orientation is very important to enhance company image and business performance of small manufacturing enterprises. For this, managers should make efforts to build effective market orientation as organizational culture to improve innovativeness, company image, and business performance.

시장지향성, 기업이미지, 경영성과 간의 영향관계

정경효(Keong Hyo Jung),정기한(Ki Han Chung) 한국창업학회 2012 한국창업학회지 Vol.7 No.2

The purpose of this study is to investigate the relationship among market orientation, company image, and business performance of small manufacturing enterprises in Korea. The results show that information dissemination and information responsiveness of market orientation affect positively company image except information generation. Information dissemination affects positively business performance except information generation and information responsiveness. However, information responsiveness affects indirectly business performance. Company image affects positively business performance. Therefore, it is identified that the role of market orientation is very important to enhance company image and business performance of small manufacturing enterprises. For this, managers should make efforts to build effective market orientation as organizational culture to improve company image and business performance.

근골격계질환 예방관리 프로그램에 대한 구조 분석 및 실무자 요구 사항 조사

정기효,이상기,권오채,유희천,김대성,Jung, Ki-Hyo,Lee, Sang-Ki,Kwon, O-Chae,You, Hee-Cheon,Kim, Dae-Seong 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.3

The KOSHA codes H-31 and H-30 provide general guidelines to establish a prevention program for work-related musculoskeletal disorders(WMSD). Understanding of the components and practitioner needs for a WMSD prevention program is necessary for effective revision and implementation of the KOSHA codes. The present study established a comprehensive structure for a WMSD prevention program and surveyed practitioner needs for the KOSHA codes. The comprehensive prevention program structure, consisting of 7 parts(organization, education, risk management, medical management, program evaluation, and record keeping) and 90 items, was constructed by analyzing WMSD prevention guidelines published by various government agencies such as KOSHA, OSHA and NIOSH. Next, 20 practitioners, from four industry sectors(auto manufacturing, auto part manufacturing, shipbuilding, and machinery), working in a safety and health department or labor union, were interviewed to collect opinions for the KOSHA codes in terms of relevance, government support, and additional information needed. Guidelines of the KOSHA codes requiring modifications and government supports were identified, which can be used to revise the KOSHA codes and to establish a government policy to promote the implementation of the KOSHA codes. Lastly, the survey revealed that integrated, customized, quantitative, and case information for WMSD prevention is additionally needed, which can be used as design guidelines for a WMSD prevention program manual for practitioners.

장갑 설계 적용을 위한 손동작에 따른 손체표의 길이변화 분석

권오채,선미선,정기효,이민정,연수민,유희천,김희은,Kwon, O-Chae,Sun, Mee-Sun,Jung, Ki-Hyo,Lee, Min-Jeong,Yeon, Soo-Min,You, Hee-Cheon,Kim, Hee-Eun 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.4

A glove design which reflects the changes in hand surface by hand motion can reduce the undesirable effects of use of gloves on hand performance. The present study examined changes in hand length dimensions due to hand motion and identified significant factors affecting the length changes. Recruiting 120 males and females in their 20s and 30s having various hand lengths, this study measured 10 hand length dimensions, defined at 2 hand areas(phalangeal and metacarpal areas) for 5 digits, when the hand is stretched and in fist, and then calculated the percentage of length increase for each dimension. ANOVA and simple-effect analyses showed the length change percentages were mainly different depending on digit and hand area: 111-127% at the phalangeal area and 112-116% at the metacarpal area. The length change percentages of the index, middle, ring, and little fingers in the phalangeal area ascended in order and showed a high correlation(r = 0.94)with the ranges of motion of the fingers.

앉은 자세에서 힘 수준에 따른 상지관절 동작별 최대 수용 반복 빈도수 분석

권오채,유희천,정기효,Kwon, O-Chae,You, Hee-Cheon,Jung, Ki-Hyo 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.2

Evaluation of repetitiveness for upper extremity intensive tasks is essential to determine the level of risk for upper extremity musculoskeletal disorders at the workplace. However, experimental data available to establish the acceptable levels of repetitiveness for various postures and forces is lacking. The present study examined the maximum acceptable frequencies(MAFs; motions/min.) of shoulder, elbow, wrist, and index finger motions at different forces(1kgf and 4kgf for shoulder, elbow, and wrist; 0.25kgf and 1 kgf for index finger) in sitting. Seventeen right-handed males in 20s without having any history musculoskeletal disorders participated in the MAF experiment. The participants determined their MAFs for the upper extremity motions by using the self-adjustment method and their work pulse(increase in heart rate; beats/min.) and rating of perceived exertion(RPE) were measured when working at MAF. The MAFs of elbow, wrist, and index finger motions for each force level were about 2, 3, and 6 times the corresponding MAF(9 at the high force and 24 at the low force) of shoulder motion and the MAFs at the low force increased about 2 times those at the high force. The work pulses of elbow, wrist, and index finger motions for each force level were 70%, 50%, and 30% of the corresponding work pulse(17 at the high force and 12 at the low force) of shoulder motion and the work pulses at the low force were about 70 % of those at the high force. Lastly, the RPEs of the upper extremity regions were about level 3(moderate) or below.

손동작에 따른 손체표 길이 변화를 적용한 장갑 설계 평가

권오채,선미선,정기효,이민정,연수민,유희천,김희은,Kwon, O-Chae,Sun, Mee-Sun,Jung, Ki-Hyo,Lee, Min-Jeong,Yeon, Soo-Min,You, Hee-Cheon,Kim, Hee-Eun 대한인간공학회 2005 大韓人間工學會誌 Vol.24 No.4

Use of a glove made of materials with a low elasticity decreases the performance of the hand such as agility, dexterity, range of motion, and grip strength. The present study examined if the adverse effects of a low-elastic glove can be reduced by a design which accommodates the changes of hand surface lengths by hand motion. Two glove designs which provide patches of elastic cloth and pleats at the finger joints and knuckle were developed by considering the hand surface length changes, and then compared with two conditions(bare hand and conventional glove design that does not consider the dynamic characteristics of the hand dimensions) in terms of completion time in peg board insertion task, maximum grip strength, discomfort in hand motion, discomfort in force exertion, and overall discomfort by 24 right-handed participants. The test results confirmed that wearing of a glove significantly reduced the agility and grip strength capability of the hand and indicated that the novel designs were effective to lessen the performance decreases compared to the conventional design. Also, of the glove designs, the pleat glove design was found most preferred for both better hand performance and less subjective discomfort.

공학교육, 엔지니어링 하우스, 산학협력, 기존공학교육, 공학교육인증

이원섭(Won Sup Lee),정기효Ki Hyo Jung),장준호(Joon Ho Chang),장수영(Soo Young Chang),전치혁(Chi Hyuck Jun),정무영(Moo Young Jung),한성호(Sung Ho Han) 한국공학교육학회 2008 공학교육연구 Vol.11 No.4

기업은 시장경쟁력 향상에 중요한 혁신제품개발을 위해 다각적으로 노력하고 있으나, 국내 대학은 혁신제품개발 전문인력 양성을 위한 교육과정 체계가 미흡하다. 본 연구는 혁신제품개발 교육과정 개발에 활용될 수 있는 교육주제, 교육방식, 그리고 산학연계방식에 대해 학생과 실무자의 요구사항을 파악하고자 하였다. 문헌조사를 통해 7개 부문(기획, 타당성 분석, concept 개발, 제품 설계, 제조 공정 설계, 생산, 윤리와 법)의 46개 제품개발 교육주제가 선정되었다. 제품개발 관련 과목 수강생(53명)과 관련업무 종사자(36명)를 대상으로 선정된 교육주제의 선호도(학생)/중요도(실무자), 교육방식 및 산학연계방식에 대한 의견이 조사되었다. 설문 분석 결과, 7개 교육 부문에 대해 학생은 균형 있는 교육을 선호하는 반면 실무자는 기획과 concept 개발 부문이 상대적으로 중요하게 교육되어야 한다고 응답하였으며, 교육주제들 중 6가지(제품개발전략, 고객요구조사, 시장조사, concept 창출 방법, 디자인 idea 생성방법, 인간공학 디자인)에 대해 학생과 실무자가 공통적으로 선호 혹은 중요시하는 것으로 파악되었다. 또한, 학생은 다양한 교육방식(이론, 토론, 발표, 실습, 사례연구)의 균형 있는 운영을 선호하며 각 교육방식에 대한 요구사항을 제시하였다. 마지막으로 산학연계방식에 대해 학생은 산업체와의 연계를 통한 실무학습 기회를 희망하였으며, 실무자는 학교와 산업체가 상호 혜택을 제공할 수 있는 방안들을 제시하였다. 본 연구에서 파악된 학생과 실무자의 요구사항은 혁신제품개발 전문인력 양성을 위한 교과과정 개발 시 유용하게 활용될 수 있을 것이다. Companies have been making considerable efforts to develop innovative products for better competitiveness in the market, however, the education curriculum for innovative product development (IPD) in domestic universities needs has not been well developed. The present study was intended to identify the needs of students and practitioners regarding teaching subjects, pedagogical methods, and industry-academia collaboration that can be reflected in the development of IPD education curriculum. Through a literature survey 46 IPD teaching subjects of 7 categories (planning, feasibility analysis, concept development, product design, manufacturing process design, production, and ethics & law) were selected. Opinions on the preferences and importances of the teaching subjects, pedagogical methods, and industry-academia collaboration were collected from 53 college students who took courses of product development and 36 practitioners working in product development. While the students preferred the balanced teaching of all the subject categories, the practitioners suggested planning and concept development be taught with high importance; 6 subjects (product development strategy, customer needs identification, market research, concept generation method, design ideation method, and ergonomic design) received high ratings of preference and importance. The students preferred the mix of various pedagogical methods (lecture, discussion, presentation, practice, and case study) and provided needs on each pedagogical method. Lastly, the students wanted an opportunity of learning through industry-academia collaboration and the practitioners provided ideas for mutual benefits between industry and academia. The needs of students and practitioners identified in the study can be effectively applied to develop a better IPD education curriculum.