• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.219-224
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• 2012

In this work, a steady-state performance modeling and off-design performance analysis of the 2-spool separate jet turbofan engine named BR715-56 which is a power plant for the narrow body commercial aircraft is carried out for engine performance behaviors investigation and condition monitoring using a commercial code MATLAB/SIMULINK. Firstly, the engine component maps of fan, high pressure compressor, high pressure turbine and low pressure turbine are generated from similar component maps using the scaling method, and then the off-design performance simulation model is constructed by the mass flow matching and the work matching between components. The model is developed using SIMULINK, which has advantages of easy steady-stare and dynamic modelling and user friendly interface function. It is found that the off-design performance analysis results using the proposed model are well agreed with the performance analysis results by GASTURB at various operating conditions.

• Journal of the Korea Society for Simulation
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• v.25 no.4
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• pp.53-63
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• 2016

This study aims to verify the feasibility of design by developing pressure flow-controlled swash plate type pump with the use of SimulationX, a computer analysis program. Developing analysis model based on design drawing data has a cost-saving effect because it is possible to figure out the effectiveness of design through the work and it never falls into repeated inaccuracies in the production process. Analysis model is developed in the following order. First, the structure of each part such as valve and rotating unit which have dynamic factor is analyzed and the modeling of single component is carried out, reflecting drawing data. Second, the modeling of pump assembly is carried out with the combination of each analysis model and a work is conducted to determine whether the modeling can perform pressure flow control function according to load condition smoothly based on design intent. At the end of the modeling process, the feasibility of design is verified by showing the parts which are moving as expected mechanism.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.8
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• pp.855-861
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• 2011

We predict the rolled-strip profile for a 6-high mill using thin rolling theory and a numerical model. In the numerical model, we calculate the distributions of the contact pressures between the rolls and the rolling pressure between the strip and the work roll in the transverse direction using the geometric structure of the 6-high mill and the boundary conditions. We determine the distribution of the rolling pressure in the rolling direction via a thin-foil rolling model using Fleck's theory. We calculate the three-dimensional elastic deformation of the work roll using the pressures of the width and rolling directions. We then obtain the three-dimensional strip profile via the elastic deformation of the work roll during the rolling process. The profile is verified by a thin cold-rolling test and FE simulation.

• Journal of Families and Better Life
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• v.9 no.1 s.17
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• pp.95-112
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• 1991

This study is planned to provide the basic idea to seek for the appropriate Time Management Strategies and to investigate the Time Management Strategies and household work time of wives. For these research tasks, the data are collected through the questionnaire rand 479 respondents were housewives in seoul. Their data are analyzed using Frequency, ANOVA, Pearson's Correlation Analysis, Simple Regression Analysis, Multiple Regression Analysis. The Major findings of this study were as follows ; 1) There are significant differences in the time management strategies according to housewife's age, education level, and employment status, children's number, the type of housing, the type family, income and sex role attitude. 2) There are significant differences in the household work time according to housewife's age, education level, employment status, family size, children's number, type of housing, income, sex role attitude and time pressure perceptibility. 3) The Household work time is found to be negatively correlated to the Time Management Stategies except the adjustment of leisure and sleep time. 4) The Household work time is significantly related to housewife's employment status and the adjustment of leisure and sleep time.

• Culinary science and hospitality research
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• v.14 no.3
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• pp.16-30
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• 2008

Rapid change of surroundings has been influencing the work environment for cooks, making it more convenient; however, there are still many difficulties to improve. Especially, cooks are exposed to lots of occupational diseases due to tension and pressure as well as noise, high temperature and humidity in their work place. This study examines cooks' operational exhaustion caused by cooking operation and cooking circumstances. The analyzed result shows the job fatigue related to the general features of the cooks(such as charged cooking part, types of engaged business, class of position, cooking career, and working hours). For example, pains on the neck, back, arms and wrist are mostly affected by the charged cooking parts. Effects related to the types of engaged business, backaches usually occurred in Catering, pains in shoulder from serving at hotels and eye-tiredness from meal serving. As for working hours, most of backaches occurred from over 13-hour-work, and pains in shoulder and eye-tiredness under 8-hour-work. Pains in legs, tiredness, and the change of weight do not have any relations withthe general features of the cooks statistically(p>0.05).

• Safety and Health at Work
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• v.5 no.3
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• pp.165-167
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• 2014

The Dutch construction industry has introduced a compulsory preemployment medical examination (PE-ME). Best-evidence contents related to specific job demands are, however, lacking and need to be gathered. After the identification of job demands and health problems in the construction industry (systematic literature search and expert meeting), specific job demands and related requirements were defined and instruments proposed. Finally, a work ability assessment was linked to the instruments' outcomes, resulting in the modular character of the developed PE-ME. Twenty-two specific job demands for all Dutch construction jobs were identified, including kneeling/squatting, working under time pressure, and exposure to hazardous substances. The next step was proposing self-report questions, screening questionnaires, clinical tests, and/or performance-based tests, leading to a work ability judgment. "Lifting/carrying" is described as an example. The new modular PE-ME enables a job-specific assessment of work ability to be made for more than 100 jobs in the Dutch construction industry.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.1047-1054
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• 2021

University academicians are playing a significant role in nation building and striving hard to impart quality education to students and also instill moral and ethical values in them. The current study aims to determine the relationship between work-life balance (WLB) and satisfaction among academicians. For the study purpose, 154 academicians from different universities with varied designations were selected randomly from the Kingdom of Saudi Arabia. Pareek et al. (2011) constructed and validated a scale to gather responses from respondents with the aim of understanding WLB in relation to satisfaction. Descriptive and inferential statistics were used to interpret the results to make the study more authentic and valuable. The study's findings revealed that (i) all facets of WLB have positive relationships with one another, resulting in workplace satisfaction; (ii) the result also reflects that male faculty members have a lot of pressure and responsibility in the universities than the female faculty members which reflect that male are more prone to dissatisfaction in comparison to the dfemale faculty members (iii) the factor personal needs is having the high degree of correlation followed by the social needs. Results indicate that WLB plays a crucial role to provide satisfaction and surely ignite new information in the contemporary knowledge of work life balance among the Saudi Arabian Universities.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.3
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• pp.76-85
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• 2022

Work situational awareness test (WSAT) has been utilized to estimate the fatigue risk of workers who worked with time pressure or latent accident risks at their work environment. Thus researchers decided to use WSAT to estimate fatigue risk of cabin crews of an airline in Korea and to analyze empirically how such risk might have an effect on cabin crew's safety behavior. This was because there had not been enough research on accessing cabin crews' fatigue and analyzing its risk for the flight safety. In addition, the mediation effect of cabin crew's planning was also analyzed through Sobel-test by researchers among external factors such as lack of concentration, attention deficit, distraction and safety behavior. According to empirical analysis, it was found attention deficit and distraction of cabin crews due to fatigue during the flight had a significant negative effect on their planning. Planning was also proven to have mediation effect to cabin crew's safety behavior.

• Journal of Drive and Control
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• v.19 no.2
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• pp.11-16
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• 2022

It is important to measure the excavator's work productivity that estimates the bucket's payloads on a process. If the bucket isn't filled at every working cycle, the excavator's operator has to drive the machine more to achieve his work quota. If bucket is filled over with the load, the other way around, the transferred object has to spread out on the workplace. That causes additional work to clean the site. This paper proposes a method that can estimate the bucket's payload to improve the excavator's work productivity. This method assumes that the excavator is a lumped mass system. And it uses a 3 points angle (boom link, arm link, swing) and 2 points pressure (boom cylinder's input port and output port) of measurable data. Depending on assumptions, the bucket's payload can be calculated by the payload's motion equation. And this suggested method can be verified by simple experiments.

• Journal of the Ergonomics Society of Korea
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• v.29 no.4
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• pp.465-471
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• 2010

Work-related musculoskeletal disorders (WMSDs) have been the most common health problem covered by worker's accident compensation insurance for several years in Korea. Korean government has strengthened related regulations since 2003. People looked forward to decreasing the incidence and prevalence of WMSDs. At first, the expectation could be realized. However, we were bumped against to limit at present. The authors think it is due to the negligence of psychosocial factors for WMSDs. Many researchers reported that the various psychosocial factors were associated with WMSDs or symptoms. Job demand, social support, job satisfaction and decision latitude are the major risk factors in job stress aspect. Work pressure, lack of rest, qualified workload, workload variability and monotonous job are the significant risk factors in work context of work organization. Employment flexibility, downsizing, lean production, contingent work and pay for by the piece are also the risk factors in an organizational context. Furthermore, these risk factors are associated with each other across different dimensions of work organization. Suggestive possible pathways between these risks and WMSDs have been taken note of increasing muscle strain or ergonomic stress and of a cognitive aspect. The authors suggest these risk factors could explain the limitation of the regulation system for WMSDs. In conclusion, the strategy to manage psychosocial factors is the one of the essential approach to prevent WMSDs.