• 한국시뮬레이션학회논문지
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• 제19권3호
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• pp.45-54
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• 2010

반도체 제조공정에 내재된 복잡성은 작업일정(job scheduling) 문제를 해석적 방법으로는 풀기 어렵기 때문에 보통 시스템 파라미터의 변화에 대한 효과를 이산사건 모델링 시뮬레이션에 의존하여 왔다. 한편 장비 고장 등 예측 불가능한 사건들은 고정된 작업일정 기법을 사용할 경우 전체 공정의 효율을 악화시킨다. 따라서 이러한 불확실성에 대해 최적의 성능을 내기 위해서는 작업일정을 실시간으로 대처 변경하는 것이 필요하다. 본 논문은 반도체 제조 공정에 대해 시스템 제어관점의 접근방법을 적용하여 이 문제에 적응형 실시간 작업제어 틀을 제안하고, DEVS 모델링 시뮬레이션 환경을 기반으로 제안된 틀을 설계 구현하였다. 제안된 방법은 기존의 임기응변적인 소프트웨어적인 방법에 비추어볼 때 전체 시스템을 이해하기 쉬우면서도 또한 추가되는 작업제어 규칙도 쉽게 추가 적용할 수 있는 유연성을 장점으로 가지고 있다. 여러 가지 실험결과 제안된 적응형 실시간 작업제어 프레임워크는 고정 작업규칙 방법에 비해 훨씬 나은 결과를 보여주어 그 효용성을 입증하였다.

• 한국산학기술학회논문지
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• 제19권5호
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• pp.216-224
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• 2018

본 연구는 제조업 사업장 남성 근로자들의 우울수준을 알아보고 직무스트레스 내용(직무의 요구도, 직무의 자율성) 및 직장의 사회적지지(상사의 지지도, 동료의 지지도)와 우울과의 관련성을 검토하는 것을 목적으로 하였다. 조사대상은 제조업 사업장 남성 근로자 428명으로 하였으며, 2017년 7월 1일부터 8월 31일까지의 기간 동안에 구조화된 무기명 자기기입식 설문지를 사용하여 설문조사하였다. 연구결과, 전체 조사대상자 중 우울경향이 있는 자(CES-D 점수 16점 이상)는 21.5% 이었다. 조사대상자의 직무스트레스 내용별 CES-D 점수는 업무의 요구도가 낮은 군보다 높은 군에서, 업무의 자율성이 높은 군보다 낮은 군에서 유의하게 높았으며, 직장의 사회적지지도별 CES-D 점수는 상사의 지지도가 높은 군보다 낮은 군에서, 동료의 지지도가 높은 군보다 낮은 군에서 유의하게 높았다. CES-D 점수는 업무의 요구도와 유의한 양의 상관관계를 보인 반면, 업무의 자율성, 상사의 지지도, 동료의 지지도와는 유의한 음의 상관관계를 보였다. 위계적 다중회귀분석 결과, 업무 요구도가 높을수록, 업무의 자율성이 낮을수록, 상사와 동료의 지지도가 낮을수록 CES-D 점수가 높은 것으로 나타났으며, CES-D 점수에 대한 설명력은 업무 요구도와 업무의 자율성이 추가됨에 따라 18.4% 유의하게 증가되었고, 상사의 지지도와 동료의 지지도가 추기됨에 따라 14.1%의 설명력이 증가되었다. 위와 같은 결과는 업무의 요구도와 업무의 자율성 및 상사와 동료의 지지도가 우울수준과 높은 관련성이 있음을 시사한다.

• 대한지역사회영양학회지
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• 제2권4호
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• pp.605-615
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• 1997

The job characteristics and competencies of 285 dietitians in employee foodservices were investigated by worker-oriented job analysis methodology. The purposes of this study were to : a) determine the knowledge, abilities, skills and other characteristics(KASO) needed for dietitians in two types of employee foodservice groups(self-operated vs. contracted), b) categorize KASO items by factor analysis and c) provide job information and job descriptions for dietitians in employee foodservices. The job analysis questionnaire was consisted of questions concerning the 134 KASO items. The questionnaire was mailed to 250 dietitians who are members of The Korean Dietetic Association Practice Group in self-operated foodservices(group A) and 250 dietitians who are employed in contracted foodservice companies(group B). Completed questionnaires were received from 285 dietitians(121 in self-operated, 164 in contracted) ; with response rate of 57%. Statistical data analysis was completed using the SPSS/win and the SAS/win packages. The results of this study can be summarized as follows. 1) Through factor analysis, the 134 KASO items were regrouped into 6 categories :‘primary dietetic tasks concerning menu management and administrative work regarding merchants’, ‘primary dietetic tasks concerning procurement and purchasing of food and supplies and meal production and service control’, ‘primary dietetic tasks concerning facility, sanitation and safety control’, ‘secondary dietetic tasks concerning nutrition education and research’, ‘secondary dietetic tasks concerning foodservice operation management’and‘human attributes’. 2) Analysis of the total scores(average scores of degree of frequency, importance and entry requirements of KASO items within 6 categories), group A showed high priorities placed on‘human attributes’, ‘procurement and purchasing of food and supplies and meal production and service control’, ‘menu management and administrative work regarding merchants’, ‘whereas group B showed high priorities placed on’‘human attributes’, ‘foodservice operation management’. (Korean J Community Nutrition 2(4) : 605-615, 1997)

• Preventive Nutrition and Food Science
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• 제2권3호
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• pp.214-218
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• 1997

The purpose of this study was to investigate the potential hypolipidemic effect of job's tears diet with the controlled intake of fiber in streptozotocin induced diabetic rats. Forty eight rats were fed either control diet or experimental diets (Raw, milled job's tears(RMJ); Raw, whole grain job's tears(RWJ);Steamed, milled job's tears(SMJ);Roasted, milled job's tears(OMJ)) for 3 weeks. The levels of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), free fatty acid(FFA) and triglyceride (TG) in plasma, liver and skeletal muscle were compared. Compared to diabetic control group, the level of plasma TC was lower in OMJ an SMJ fed rats, and was not different from that in RMJ and RWJ fed rats. The level of LDL-C was significantly lower in RMJ, OMJ and SMJ fed rats. For plasma HDL-C levels, no difference was observed among all group. Plasma FFA level significantly lower in RMJ, SMJ and RWJ fed rats, Plasma TG a levels of all job's ears fed groups were 50∼70% lower and liver TG levels of all job's tears fed groups were 70∼80% lower than those fo diabetic control group. For muscle TG, no differences were seen among all groups. These results suggest that steamed job's tears and roasted job's tears could have the potentaila on improving lipid profile fo diabetes in clinical setting and the different cooking methods of job's tears might affect the lipid profile of the diabetic rats.

• Journal of Preventive Medicine and Public Health
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• 제31권4호
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• pp.719-727
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• 1998

This study was carried out to assess the relationship between jobstrain, psychosocial distress and homocysteine. The study design was cross-sectional, and included 152 industrial workers in middle sized city. A self-adminstered questionnaire measured general characteristic, job strain and psychosocial distress. Blood was drawn into EDTA tube, and total plasma homocysteine was measured by HPLC. Homocysteine in the high job demand group was sagnificantly higher than that in the low job demand. Cholesterol in the high job control group was significantly higher than that in the low job control. Homocysteine was significantly higher in the high job strain group than that in the other group. Folate and vitamin B12 showed a significantly negative correlation with homocysteine. Multiple regression analysis was used to determine whether the psychosocial distress and other variable contributed to explaining the homocysteine. Stress correlates with the homocysteine.

• 한국경영과학회지
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• 제16권2호
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• pp.125-125
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• 1991

This paper presents a framework for the hierarchical PPC(Production Planning and Control) in make-to-order environment with job shop. The characteristics of the environment are described as : 1) project with non-repetitive and individual production, 2) short delivery date, 3) process layout with large scales manufacturing. 4) job shops. The PPC in a make-to-order typically are organized along hierarchical fashions. A model is proposed for the hierarchical job shop scheduling based on new concepts of production system, work and worker organization. Then, a new integrated hierarchical framework is also developed for the PPC based on concepts of the proposed job shops scheduling model. Finally, the proposed framework has been implemented in the Electric Motor Manufacturing and the results showed good performance.

• 경영과학
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• 제16권2호
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• pp.125-135
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• 1999

This paper presents a framework for the hierarchical PPC(Production Planning and Control) in make-to-order environment with job shop. The characteristics of the environment are described as : 1) project with non-repetitive and individual production, 2) short delivery date, 3) process layout with large scales manufacturing. 4) job shops. The PPC in a make-to-order typically are organized along hierarchical fashions. A model is proposed for the hierarchical job shop scheduling based on new concepts of production system, work and worker organization. Then, a new integrated hierarchical framework is also developed for the PPC based on concepts of the proposed job shops scheduling model. Finally, the proposed framework has been implemented in the Electric Motor Manufacturing and the results showed good performance.

• 한국산업보건학회지
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• 제29권1호
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• pp.108-118
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• 2019

Objective: The purpose of this study was to investigate the effects of occupational stress factors on the level of stress and depression of entertainment program producers and entertainment program writers. Methods: This study was based on analysis of a survey collected by 65 respondents out of 224 questionnaires who are entertainment program PDs and entertainment program writers. The survey was conducted from December 20, 2017 to February 20, 2018. Results: In the logistic regression analysis conducted to investigate the factors affecting the stress level in the job-related characteristics of a) higher total career, b) shorter working period in the current firm, c) longer weekly working hours and d) more count of weekend work, the results found higher stress levels. In the sub-factors of job stress, the stress level encountered by respondents was significantly higher for those with a) higher job demand, b) lower insufficient job control and c) higher job instability. In the logistic regression analysis conducted to investigate the factors affecting depression, the depression level in entertainment PD was higher than the entertainment writer in the sociodemographic characteristics. In the sub-factors of job stress, the stress level was significantly higher for those with higher job demand, lower insufficient job control, and higher job instability. For job-related characteristics, depression was significantly higher for longer weekly working hours. Conclusions: Entertainment program producers and entertainment program writers suffer from psychosocial stress and depression which are caused by excessive job demands, lack of job autonomy and job instabilities. Those factors must be managed and also their workweek should be shortened.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.1095-1098
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• 1993

This paper presents linear programming neural networks for job-shop scheduling. The starting times of tasks and constraints are formulated as the linear programming problem. A modified Hopfield neural network is proposed for solving job-shop scheduling.

• 산업경영시스템학회지
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• 제33권3호
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• pp.208-218
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• 2010

The purpose of this study is to examine the dynamic relationships among locus of control as a individual traits, the three organizational equity factors(distributive equity, procedural equity and interactional equity), individual attitudes and behaviors(job satisfaction, organizational commitment and turnover intention). In this study, we designed research model based on extensive literature review and tested each hypothesis through empirical analysis of which single public organization was the subject. The results are as follows : locus of control negatively affect all the three equity factors. And distributive equity positively affect job satisfaction whereas both procedural equity and interactional equity positively affect organizational commitment. Also only organizational commitment not job satisfaction positively affect turnover intention. The various implications to manage organizational equity, job satisfaction and organizational commitment and the limitations of the study and directions for future research were discussed.