• 제목/요약/키워드: Physical workload

검색결과 162건 처리시간 0.025초

전투기 AESA 레이더 운용모드의 최적 계층구조 설계 방법론 (Optimal Hierarchical Design Methodology for AESA Radar Operating Modes of a Fighter)

  • 김흥섭;김성호;장우석;설현주
    • 산업경영시스템학회지
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    • 제46권4호
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    • pp.281-293
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    • 2023
  • This study addresses the optimal design methodology for switching between active electronically scanned array (AESA) radar operating modes to easily select the necessary information to reduce pilots' cognitive load and physical workload in situations where diverse and complex information is continuously provided. This study presents a procedure for defining a hidden Markov chain model (HMM) for modeling operating mode changes based on time series data on the operating modes of the AESA radar used by pilots while performing mission scenarios with inherent uncertainty. Furthermore, based on a transition probability matrix (TPM) of the HMM, this study presents a mathematical programming model for proposing the optimal structural design of AESA radar operating modes considering the manipulation method of a hands on throttle-and-stick (HOTAS). Fighter pilots select and activate the menu key for an AESA radar operation mode by manipulating the HOTAS's rotary and toggle controllers. Therefore, this study presents an optimization problem to propose the optimal structural design of the menu keys so that the pilot can easily change the menu keys to suit the operational environment.

치과위생사의 소진과 직무만족도 및 이직의도의 관련성 (Analysis of the Correlation of Burnout, Job Satisfaction and Turnover of Dental Hygienists)

  • 이병호;김정술
    • 한국콘텐츠학회논문지
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    • 제10권11호
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    • pp.217-227
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    • 2010
  • 부산, 울산 및 경남지역 소재 치과병의원에 근무하는 275명의 치과위생사를 대상으로 소진, 이직과 직무만족도에 관한 상관관계를 조사한 본 연구에서 얻은 결론은 다음과 같다. 1. 치과위생사의 업무와 관련된 소진 정도는 신체적 탈진감 3.41, 직업효능감 감소 2.77, 감정적 고갈 2.76순이었고, 전체 소진 평균은 2.61로 조사되었다. 2. 소진의 하위영역 중 감정적 고갈이 직무만족도에 가장 큰 영향을 미쳤으며, 직업효능감 감소, 신체적 탈진감 순으로 조사되었으며, 모든 요인들은 음의 상관관계로 나타나 소진이 낮을수록 직무만족도가 높은 것으로 나타났다. 3. 직무만족도의 하위영역 중 의사소통, 업무요구량, 자율성, 조직의 합리성, 장래성 순으로 이직의도에 영향을 미치는 것으로 조사되었으며, 모든 요인들은 음의 상관관계로 나타나 직무만족도가 낮을수록 이직의도가 높은 것으로 조사되었다.

거리환경미화원의 근골격계 증상의 특징 및 인간공학적 평가 (Ergonomic Workload Evaluation and Musculo-skeletal Symptomatic Features of Street Cleaners)

  • 이향기;명준표;정은희;정혜선;구정완
    • 대한인간공학회지
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    • 제26권4호
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    • pp.147-152
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    • 2007
  • The aim of this study was to evaluate the musculo-skeletal symptomatic features of municipal sanitation workers and to compare differences of the musculo-skeletal symptoms by work types. We conducted descriptive cross-sectional survey concerning the musculo-skeletal symptomatic features of 315 street cleaners in Seoul and GyeongGi Province, Korea, during 2 weeks of September 2006. Questionnaires were consisted of general characteristics, occupational characteristics and musculo-skeletal symptoms. And we observed their works and evaluated their movement and posture by REBA. For work types, tools and subjective physical work loading, there were statistical difference whether or not NIOSH symptom positive on upper limb. Musculo-skeletal symptoms on upper limb were claimed from 43.2% of street cleaners, more than in 32.4% of cleaners. Musculo-skeletal symptoms on upper limb were reported higher in the group who felt their subjective physical work loading severe than in the otherwise group. The REBA results were over 'high risk stage' in street cleaners. Street cleaners had more repetitive motions than solid waste collectors on upper limbs. Works according to the criteria of musculoskeletal burdened work by the Ministry of Labor results were over 'high risk stage' of No. 2 and No. 4 in street cleaners. We found that street cleaners complained musculo-skeletal symptoms on upper limb more than solid waste collectors. This study suggests that it is necessary for street cleaners to carry out the prevention program of musculo-skeletal diseases. For street cleaner, the measure plans such as job rotation, automatic street sweepers, reducing work hours are helpful in preventing musculoskeletal symptoms on the upper limb.

가상화 환경에서 부하균형을 위한 가상머신 동적 재배치 (Dynamic Relocation of Virtual Machines for Load Balancing in Virtualization Environment)

  • 사성일;하창수;박찬익
    • 한국정보과학회논문지:시스템및이론
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    • 제35권12호
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    • pp.568-575
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    • 2008
  • 서버 가상화 기술에 의한 서버 통합은 효율적인 자원 사용에 따른 비용적인 장점이 있다. 그러나 하나의 물리적 장치에 여러 개의 서버가 가상머신으로 함께 동작함으로써 더욱 복잡한 부하특성을 가지게 되었다. 따라서 이를 해결하기 위한 효율적인 자원관리 방법이 요구된다. 이러한 문제에 대한 해결방법으로 제안된 것이 가상머신 이동(live migration)[1,2]을 이용한 가상머신 동적 재배치 기법이다[3,4]. 본 논문은 가상머신 동적 재배치 알고리즘에 있어서 각 자원요소(CPU, network I/O, memory)들의 활용률을 다차원 공간상에서 분석하여 조율함으로써 서버통합의 자원 효율성을 증가시키는 방법(Server consolidation optimizing algorithm)을 제안하고 있다. 실험을 위해서 여러 대의 통합서버와 수많은 서비스를 생성하여야 하는 어려움이 있기 때문에 본 논문에서는 기업환경에서의 서버 가상화 프로젝트 경험을 바탕으로 서버의 부하변화와 유사한 패턴의 모니터링 데이타들을 정의하여 수치적인 시뮬레이션을 통해 sandpiper[3]와 SCOA 알고리즘의 부하 균형에 대한 효율성을 비교하였다.

최대 산소소모량 평가에 있어서 자전거 에르고미터를 이용한 최대하부하검사방법의 타당도 (Validity on Submaximal Load Tests Using Cycle Ergometer in Evaluation of Maximum Oxygen Consumption Volume)

  • 강동묵;박용균;이용환;설진곤
    • 한국산업보건학회지
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    • 제16권2호
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    • pp.145-151
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    • 2006
  • Because of the limitations of maximal load tests for $VO_2max$, submaximal tests using cycle ergometer are used for field study in general. This study was conducted to evaluate validity of various submaximal tests using cycle ergometer. This study had been conducted during May to June 2005, which subjects were 15 males and 15 females in twenties. Experiment was performed with restrictive conditions which regulated ambient temperature, noise, and entrance restriction. Submaximal load test protocols including YMCA Protocol (YP), ${\AA}strand$-Rhyming Protocol (ARP), Relative heart ratio Protocol (RP), and Ramp test Protocol (RP) were compared with maximal load test which used gas mask analyser using Bruce Protocol. All submaximal load tests were highly related with maximal load test (Spearman's correlation coefficient > 0.60) with statistical significancy. The highest correlation coefficient with maximal test was found in RP. Three submaximal test results except RP were significantly different with maximal test results (Wilcoxon rank test). All submaximal tests had high validity. The reason why RP had highest validity might be that it represents Korean physical strength and individual differences better than the others. RP using cycle ergometer would make easy to study for physical capacity evaluation and field workload estimation.

일부 치위생과 학생의 스트레스원과 대처방식에 관한 연구 (A study on the stressors and coping patterns of some dental hygiene students)

  • 박일순;이선희
    • 한국치위생학회지
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    • 제8권4호
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    • pp.251-263
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    • 2008
  • Purpose : The purpose of this study was to examine the stressors and coping patterns of dental hygiene students in a bid to boost the efficiency of guidance and counseling. Subjects and Method : The subjects in this study were 359 dental hygiene students from some colleges. After a survey was conducted, the collected data were analyzed with SPSS 13.0 program. Statistical data on frequency and percentage were obtained, and ANOVA and t-test were utilized. Findings : 1. The dental hygiene students investigated suffered the most stress with excessive workload, and anxiety about the national examination was the greatest stressor. Among the areas of stressors, school life put the most pressure on them(3.25). 2. The most dominant way for the dental hygiene students to handle stress was talking with friends(4.32). Out of the areas of stress-coping patterns, mental coping was most prevalent(2.94), and the least common stress-coping area was physical coping(2.23). 3. As for the relationship between the place where they were raised and stress-coping styles, physical coping and direct coping were more widespread among the students who were brought up in large urban communities than the others. Conclusion : As the dental hygiene students were different in stress-coping styles according to the place where they were grown, educators who nurture dental hygienists should offer customized education and counseling in consideration of where students were brought up.

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포도 수확 작업의 작업특성에 따른 손목과 팔꿈치 각도 영향 분석 (The Effects of Work Characteristics of Grapes-harvesting Tasks on the Wrist and Elbow Angles)

  • 김지혜;이인석
    • 대한인간공학회지
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    • 제36권5호
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    • pp.589-599
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    • 2017
  • Objective: The objective of this study was to measure the upper-limb motions and postures of grapes-harvesting tasks using electrical goniometers and analyze the upper-limb motions in a kinematic way to assess the risk of musculoskeletal disorders. Background: Grapes farmers are exposed to various risk factors of musculoskeletal disorders (MSDs) such as repetitive upper-limb motions, non-neutral postures, and manual handling of heavy items. The farmers have to use scissors repetitively while harvesting grapes with their being arms elevated over the shoulder height, which presumed to increase the physical workload. It has been reported that the grapes farmers feel the harvesting task as the one of the hardest work in cultivating grapes. We tried measure the wrist and elbow angles while the farmers were carrying out harvesting tasks to understand how much workload the work impose on the farmers, which can be helpful in making interventions of preventing musculosksletal disorders among grapes farmers. Method: We measured joint angles at the right wrist and elbow with a wireless measuring system with two electrical goniometers from five grape farmers. The grapes-harvesting task was classified into 6 different subtasks: 1) searching, 2) picking, 3) cleaning, 4) carrying, 6) storing, and 7) miscellaneous tasks. The subtasks were compared by mean angles, 10%, 50%, and 90% APDF values of wrist flexion/extension, ulnar/radial deviation, and elbow flexion. Results: The Kruskal-Wallis tests showed that the 10th percentiles of APDF of ulnar/radial deviation and flexion/extension of the wrist significantly differs among subtasks (p<0.05). It was found that the farmers assumed more deviated wrist postures in the ulnar direction when they picking and adjusting the grapes. The use of scissors seemed to force the farmers to severely bend their wrist in the directions of ulnar deviation and flexion. The grapes-harvesting task showed similar wrist postures and motion with poultry deboning and milking tasks. Conclusion: The grapes harvesting tasks make the farmers take ulnar deviated and extended postures in the wrist. The use of scissors makes them take more severely deviated postures in the wrist. Safety guidelines including use of ergonomic scissors can be provided to the farmers to improve their work conditions. Application: The results of this study can be used as a basic data for the development of safety guidelines for agricultural work.

물리치료사의 업무 스트레스 현황과 대응수준 -부산지역을 중심으로- (An Analysis of Work Stress of Physical Therapist and Reaction)

  • 동종익;류황건;배성권
    • 보건의료산업학회지
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    • 제2권1호
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    • pp.37-55
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    • 2008
  • This study aims to enhance work efficiency and satisfaction by offering data that make a physical therapist cope with stress coming from the job efficiently by identifying and analyzing the job satisfaction and work stress perceived by a physical therapist, and the level of reaction of a physical therapist. The study distributed survey questionnaires to 300 physical therapists working in medical institutions in Busan via mail and by visit from March 3, 2007 by selecting them simply and randomly from the physical therapist list, and collected the questionnaires by March 20, 2007, 103 respondents were working at 17 general hospitals including a university hospital, 65 respondents at 12 medical centers, and 79 respondents at 39 doctor's offices. The study collected 251 copies, which showed the collection rate of 83.7%, and analyzed 247 copies (82.3%) excluding 4 copies of insincere answers. As a research tool for measuring job satisfaction the study used a tool employed for research into the job satisfaction of physical therapists who work at medical institutions in Gwangju, Jeonnam, and Jeonbuk by Kim Hee-Gwon(1992) and research regarding job satisfaction by Jeong Jeong-Hee(2004) as well as research regarding the factors of job satisfaction by Flippo(1980) & Seberhagen(1970) after adjusting the research tools to the purpose of the study. Also for questions about work stress, the study employed nurses' job stress measurement tool developed by Kim Mae-Ja and em Mi-Ok(1984) by modifying the tool to the purpose of the study, and for a measurement tool for reaction to stress, the study used a tool employed for research into reaction to stress of nurses at general hospitals by Choi Eun-Deok(2005) without modification. For data analysis, the study used the SPSS12.0 as a statistical method, and then used t-test or ANOVA for verifying actual numbers, percentile, average :score, standard deviation, rank, and difference. Also, the study conducted which is a post-test method for variables that show a significant difference at the level of p<.05 level after the analysis. The findings include the following. 1) The respondents' job satisfaction score was 3.21 points on the average (out of 5 full points). The peer relationship ranked the highest, posting 4.02 points on the average, and the job satisfaction with rewards was proven the lowest, posting 2.51 points. For the job satisfaction level by characteristics, there were significant differences (p<.05) in gender, hospital type, weekly working hours, monthly working days, number of patients per day, department in charge of therapy, and number of peers, and there was no significant difference in characteristics other than that. 2) The respondents' work stress score was 2.72 points (out of 5 full points) on the average. The respondents were shown to be under the highest stress when they suffered from excessive workload, posting 3.49 points on the average, and they were shown to be under the least stress when they had a conflict with peers at another department, recording 1.90 points on the average. for the job stress level by the characteristics of job, there was a significant difference in the reflection of job assessment(p<.05). 3) 1n respondents' reaction to stress, most of them were shown to make efforts in coping with stress, posting 2.80 points (out of 5 full points). For their experience of being wider stress, they answered that 'they felt depressed (2.85 points)" for their experience of coping with stress, they answered that 'they were indifferent to it or thought about something else' (2.62 points). Also, for their efforts in coping with stress, they answered that 'they were motivated to remove their strain by taking leave, playing, or using their preferences' (3.52 points), which ranked higher. For the level of reaction to stress by characteristics, there were significant differences by age, gender, marital status, total service years as a physical therapist, monthly working days, and department in charge of therapy(p<.05). It is necessary to offer correct information by conducting an in-depth analysis of the stressful situations of physical therapists who exert efforts in rehabilitating patients at hospitals by factor, and seeking management plans based on the research results. Also, it is necessary to develop a program for coping with stress efficiently for removing stress and to conduct research into the understanding and cooperation of administrators and persons in charge of physical therapists for reducing physical therapists' stress at hospitals.

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학교급식 조리종사원의 안전사고 실태 및 신체적 피로도 분석 (Safety Accidents and Physical Fatigue of School Foodservice Employees)

  • 조연정;김현아
    • 한국식품영양과학회지
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    • 제42권9호
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    • pp.1482-1491
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    • 2013
  • 본 연구는 향후 학교급식 안전관리 개선 방안 모색에 도움이 되고자 경남지역 초 중 고등학교 조리종사원을 대상으로 학교급식소 안전사고 실태 및 신체적 피로도를 분석하고자 수행되었다. 2011년 12월 1일부터 20일까지 총 300부의 설문지를 배부하여 276부가 회수되었고, 이 중 응답 내용이 불충분한 54부를 제외하고 총 222부(74%)를 최종 분석 자료로 사용하였으며, 본 연구 결과의 요약은 다음과 같다. 첫째, 안전사고 유형별 경험 유무 및 발생 빈도 조사 결과 타박상 경험자는 92.8%, 화상 경험자 73.0%, 피부외상 경험자 69.4%, 염좌 경험자 47.7%, 낙상 경험자 42.8%, 골절 탈구 경험자 31.5%, 감전사고 경험자 2.7% 순으로 나타났으며, 안전사고 유형별 발생 정도는 화상 2.04, 타박상 3.18, 염좌 1.64, 피부외상 2.07, 감전사고 1.06, 골절 탈구 1.42, 낙상 1.52로 나타나 타박상의 경험율 및 발생 빈도가 가장 높았다. 둘째, 노동 강도가 가장 크다고 생각되는 작업공정으로는 청소(55.4%), 안전사고가 가장 많이 발생하는 작업공정으로는 주조리 과정(48.6%), 급식소 안전사고의 주된 원인으로는 조리종사원의 과도한 업무량(3.52)이 조사되었다. 셋째, 조사대상이 작업 시 자각하는 신체적 피로도는 팔과 손목의 통증 4.18로 가장 높게 나타났으며 어깨의 통증 4.10, 척추의 통증 3.88, 빠른 피로감 3.81, 눈의 피로 3.70, 다리의 통증 3.69, 발바닥과 발목 통증 3.62, 귀의 이상 3.63, 목의 통증 3.45, 체중의 변화 3.21, 두통 2.95의 순으로 분석되었다. 넷째, 학교급식 조리종사원의 신체적 피로도에 영향 미치는 요인은 학교급(P<0.05), 1일 급식횟수(P<0.05), 1일 급식인원(P<0.001), 조리종사원 1인당 급식인원(P<0.05), 근무전 준비 운동 여부(P<0.05)로 중학교, 1일 3식을 제공하는 학교, 1일 급식 인원이 1,000명 이상인 학교, 조리종사원 1인당 급식인원이 110명 초과인 학교의 조리종사원의 신체적 피로도가 높았으며, 준비운동을 하는 경우 신체적 피로도가 낮았다. 본 연구 결과로부터 다음과 같이 제언하고자 한다. 첫째, 학교급식 조리종사원들이 가장 많이 안전사고가 발생한다고 생각하는 작업공정은 주조리 과정으로 이에 대한 정확한 작업환경을 진단하여 인체공학적 작업환경 개선이 이루어져야 할 것이다. 둘째, 노동 강도가 가장 크다고 생각하는 청소 과정에서 무거운 물체를 들거나 반복동작으로 의한 근골격계 질환 예방하기 위해 관련시설 및 장비의 보완이 필요하겠다. 셋째, 노동량의 증가에 따라 신체적 피로도가 증가함을 알 수 있었으므로 조리종사원의 적정 인력기준에 대한 후속 연구가 필요하다고 사료된다. 넷째, 준비운동을 할 때 신체적 피로도가 낮은 것으로 나타났으므로, 근무 시작 전 준비운동이 이루어지도록 충분한 교육이 이루어져야 하겠다.

빅데이터 환경에서의 B-tree 구조 기반 링크정보 관리서버의 개발 (A Study on the Link Server Development Using B-Tree Structure in the Big Data Environment)

  • 박승범;황종성;이상원
    • 인터넷정보학회논문지
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    • 제16권1호
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    • pp.75-82
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    • 2015
  • 주요 기업들과 포털들은 사용자들에게 웹 기반 환경에서 보다 효율적인 콘텐츠 이용을 지원하기 위해 이른바 콘텐츠관리시스템(CMS, Contents Management Systems)과 콘텐츠의 데이터베이스 내 물리적 주소를 연결하여 관리하는 링크 서버를 적극적으로 도입하고 있다. 이를 통해 웹브라우저 화면에서 보여지는 콘텐츠의 URL과 실제 데이터베이스 안의 콘텐츠의 물리적 주소를 자동으로 연결해 주고, URL이나 데이터베이스의 물리적 주소의 변경시 두 주소를 재 연결하는 역할을 수행한다. 최근 빅데이터 환경의 도래에 따라 디지털 콘텐츠와 사용자 접속수가 폭발적으로 증가하고 있는 상황에서 CMS와 링크 서버에서 수행해야 하는 유효 링크 검사 횟수도 따라서 증가하고 있다. Peta-Byte 또는 Eta-Byte 환경 하에서 수행되는 유효 링크 검사를 기존 URL 기반의 순차적 방식으로 수행할 경우 속도저하에 따른 데이터 링크 식별률(identification rate)의 저하와 빈번한 링크 검사에 따른 데이터베이스에 부하를 주는 요인으로 작용될 수 있다. 따라서, 본 연구는 상기와 같은 종래의 문제점을 해결하기 위해 대량의 URL에 대해 B-Tree 기반의 정보식별자의 구간별 개수 분석을 기반으로 URL 삭제 링크 및 추가 링크를 인식하고 효과적으로 관리하는 것이 가능하도록 해주는 링크 서버를 제공하는 데 있다. 본 연구를 통해 기존 방식보다 빠르고 낮은 부하를 주는 데드 링크 체크 처리가 가능해 질 것이다.