• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.2
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• pp.217-228
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• 1994

This paper presents a new integer formulation (Type III ALB) for a single model assembly line balancing problem. The objective of the formulation is to minimize the total idle time, which is defined as the product of the number of work stations and the cycle times minus the total work content. This formulation considers currently existing Type I (minimizing the number of work stations for a given cycle time) and type II (minimizing the cycle time for a given number of work stations) formulations as its special cases and provides the global minimum solutions of the cycle time and the number of work stations. This information would be of great value to line designers involved in designing new assembly lines and rebalancing old lines under flexible conditions. Solution methods based on combination of Type I and Type II approaches are also suggested and compared.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.171-174
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• 2009

The standard estimation system, used to estimate the predetermined cost of construction work, is measured by the standard and typical construction methods and field conditions. And the standard estimation system is applied to basic data for the measuring of construction cost, such as the consumed quantity of material, labor hours, and machinery cost. However it does not reflect sufficiently for the diversity and reality of constructions work Therefore, this study is recognized the necessity of new cost estimation models for the rational construction cost estimation. To improve estimation technique and construction ability, it was analyzed labor hours, production volume based on the work crew in construction work.

• Smart Media Journal
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• v.11 no.10
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• pp.36-45
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• 2022

This study was promoted to prepare an ESG-oriented work system for Korea Expressway Corporation through sustainable highway construction, IOT-based smart highway preparation, and establishment of a broad convergence business governance system between multiple ministries and implementing entities. Based on the 2nd Basic Plan for Landscape Policy (2020~2024) and the Public Design Promotion Act (2018~2022), the study was conducted through the improvement of the highway design method to be applied for four years from 2021 to 2024, the changes in construction and social conditions related to expressways, the analysis of policies and plans to secure consistency with the 'Korean New Deal', and the analysis of the project performance and work promotion system that the Korea Expressway Corporation's business execution organization has promoted together with each government department. The results of this research are expected to help the Korea Expressway Corporation establish the 21st Innovation Plan for the phased construction of a "100-years landscape with people" and the preparation of a sustainable future highway environment creation project for the lives and safety of the people.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.52
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• pp.241-246
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• 1999

In this study, to specify an evaluation of human sensibility, the types of color, intensity of illuminations and lights consisting work environmental condition are decided, and image data from examining the change of human sensibility followed by changes of the above three conditions are obtained. Using the factor analysis and quantification theory in multi-variate analysis type of Sensibility Ergonomics, determinating the structure of factors, specifying the relations of environmental conditions and factors can be done so that the structure of image on human sensibility space with the change of environmental conditions is analyzed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.3
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• pp.191-200
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• 2021

This paper deals with the boundary conditions of the stress resultants at the mid-arc for free vibration analyses of the arch. The considered arch is a horseshoe symmetric elliptic arch. The work dealing with the boundary conditions of the deflection at both ends of the arch has already been reported in the open literature. This revisited paper aims to study the suitability of the boundary conditions of the stress resultants at the mid-arc to be replaced by the boundary condition at both ends. In this study, the boundary conditions of the stress resultants at the mid-arc are newly derived based on the theory of the previous work, and natural frequencies and mode shapes are obtained using the new boundary conditions of the stress resultants. The numerical results of this paper confirm that the new boundary conditions have been validated according to previous studies and results of finite element ADINA.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.383-393
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• 2019

Objectives: The proportion of those working beyond 53 hours a week in 2018 has reached 16.8% of the total number of workers in the Republic of Korea (Statistics Korea, 2018). Although there are many studies that have dealt with the correlation of long working hours and increasing risk of work-related health problems, studies dealing with the factors impacting work-related health problems of workers according to their working hours are few. This study aims to ascertain factors impacting work-related health problems of workers based on their working hours through thorough research on their work environment. Methods: Necessary factors for this study were extracted from 'the 4th Korean Working Conditions Survey to analyze details on normal characteristics and work environments used for the study analysis, work hours, and health problems related to work. Results: The results are as follows: First, men showed a greater probability of exposure to work-related health problems than did women, especially in the 50s age group, which showed the highest potential for health problems from work among age groups. Second, service providers and sales professionals showed a higher probability of work-related health problems. Third, for the work environment, health problems at work related to vibration, noise, chemical and poison exposure, exhaustion, pain, standing position, and repeated motion showed a higher probability if the work hours are long. Conclusions: This study suggests that the minimization of overtime labor would prevent work-related health problems and diseases, improve the well-being of workers, and decrease the negative impact on workers in the subject area.

• Journal of the Korean Society of Safety
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• v.39 no.1
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• pp.55-61
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• 2024

In response to the COVID-19 pandemic, the logistics industry in Korea has rapidly been expanding, with offline demand concentrating on online platforms owing to the development of digital infrastructure. This has increased the workload of courier drivers considerably, along with labor intensity. A delivery driver died recently from overwork due to the continuous increase in delivery volume, which raises social concerns. Delivery drivers work long hours, (over 12 hours) and are greatly affected by weather conditions, such as snow, rain, heat waves, and cold waves. In addition, they lack a fixed workplace; perform atypical work handling workpieces of various sizes, weights, and shapes; and spend a large amount of time driving as part of their work. This work involves a high level of tension and requires attention and concentration. Despite the frequency of industrial accidents in the courier industry, studies on safety and health to quantitatively analyze and systematize the work of courier workers are very scarce. Therefore, to define the work process necessary for investigating the harmful factors in delivery service and the work analysis, this study conducted interviews and on-site surveys to analyze the unit work of the delivery service by targeting delivery workers. In other words, a framework of unit work for work analysis was presented to enable research and analysis by considering the aforementioned characteristics of the courier industry. The process was broadly divided into work, transport, storage, delay, and inspection. Work was divided into loading, sorting, unloading, and door subcategories, and transportation was divided into vehicle, cart, and walking subcategories as well as 10 small processes. Moreover, 22 unit works were again drawn by conducting field surveys and interviews. The risk of unit work derived from this study was ergonomically evaluated, and the ergonomic analysis revealed that uploading and transportation were the most dangerous. The results of this study could be used as basic data for preventing industrial accidents among courier workers, whose work has increased with the logistics volume and the development of the logistics industry.

• Korean Journal of Construction Engineering and Management
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• v.2 no.4 s.8
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• pp.48-61
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• 2001

This study aims at improving work reliability. It proposes a way to overcome the limitations of current scheduling methods by providing a new framework, CPAM(Construction Process Analysis Model) based on the lean principles. It suggests methods which improve work reliability and production effectiveness with variability control methods. Also it suggests methods which reduce inventories of materials and equipment and WIP(Work In Process) using two techniques; Lookahead Schedule and Weekly Work Plan. The contribution of this research also includes that it assumes planning as a process of reducing uncertainty and maximizing throughput, counter-posing plan reliability to resource redundancy as alternative strategies for managing in conditions of uncertain work flow.

• Korean Journal of Rural Living Science
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• v.5 no.2
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• pp.159-169
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• 1994

The Purpose of this study was to investigate the actual conditions of rural housewife's sex role attitude, the value consciousness of home management and the satisfaction of household work. Further, basic data for the improvement of the satisfaction of household work and the value consciouseness of home management will be produce through grasping the relationship of them. For these purposes, the data were collected by using questionnaire distributed to 292 housewives living in Cheong Song. The data were analyzed using descriptive statistics, One Way Anova, Pearson's Correlation analysis and Multiple Regression analysis. The results of the research were as follows : 1. Rural housewife's sex role attitude comparatively took the transitional position and the value consciousness of home management was modernized. Housewife's satisfaction of household work was generally usual. 2. There were significant differences in the sex role attitude according to the type of housing. 3. The value consciousness of home management of rural housewives was variable according to housewife's occupation, husband's occupation and the type of housing. 4. Among the independent variables, the number of family member, the number of children and family style. 5. There were significant differences in the satisfaction of household work according to housewife's sex role attitude. 6. Among the independent variables, the number of children, monthly family income, the sex role attitude, the value consciousness about household work, education and leadership had significant influence on the satisfaction of household work.

• The Korean Journal of Community Living Science
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• v.24 no.1
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• pp.119-132
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• 2013

This study aims to understand potential gender differences in the association between job characteristics and job satisfaction among older workers. The data are from 506 males and 202 females older than 55 from the first wave of the Korean Longitudinal Study of Ageing(KLoSA). Analyses focused on examining gender differences in the influences of subjective evaluation of work characteristics measured with education and skill fits of the work, work demands, customary early retirement, as well as more objective job conditions assessed with insurances by the employer, work hours, and salary on job satisfaction. Regression analyses revealed that female workers showed higher job satisfaction while job characteristics worked differently between genders to affect job satisfaction. For males, fitting the job with education and job demands were determining factors of job satisfaction, while the job with skills and work hours appeared to be significant factors for females. Results suggest that opportunities to utilize older workers' human capital and flexible working hours, especially for females workers would be helpful in promoting older adults' employment and satisfaction about their work.