• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.8
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• pp.742-752
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• 2010

In case of the working machine that using in the loud-noisy workplace, as it generates the loud-noise, it is influencing a physical, mental bad effect to those workers. Accordingly, though the noise countermeasure for the loud-noisy workplace is acutely requiring, until now, those methods that wearing the soundproof-protection tool, or restriction the working hours, and minimize the noise exposure volume, were mainly used. However, such noise countermeasures occur many problem points. On such point of view, using the acoustic simulation technique, let the workers to choose the workplace where suffering many damages due to the noise of working machine, and after grasp the physical property of working machine and indoor acoustic characteristic, this Study has attempted to grasp the reduction degree of noise level at before-improvement?after-improvement, through the sound-absorption measure. Passing through such preceding step, using auralizational technique based on the noise of working machine of before-improvement after-improvement, and by conduct psycho-acoustics evaluation, this study intended to investigate the change degree of subject reaction. As the result of evaluation, it is considering that the noise-reduction countermeasure method for the loud-noisy workplace could be much effective, through the sound-absorption measure.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.305-314
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• 2012

The purpose of this study was to investigate the effects of joint kinetics and coordination on within-individual differences in maximum vertical jump. 10 male subjects aged 20 to 30 performed six trials in maximum vertical jump and with based on jump height the good(GP) and bad(BP) performances for each subject were compared on joint kinetics of lower extremity and coordination parameters such as joint reverse and relative phase. The results showed that maximum moment, power, and work done of hip joint and maximum moment of ankle joint in GP were significantly higher than that in the BP but no significant differences for the knee joint. We could observe a significant difference in joint reverse timing between both conditions. And also the relative phase on ankle-knee and ankle-hip in GP were significantly lower than that in the BP, which means that in GP joint movements were more in-phase synchronized mode. In conclusion, mechanical outputs of hip and ankle joints had an effect on within-individual differences in vertical jump and the inter-joint coordination and coordination including sequence and timing of joint motion also might be high influential factors on the performances within individual.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.612-615
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• 1996

In the continuous casting process, molten metal contacts the mold wall and the molten metal surface is subject to the mold oscillation. The mold oscillation results in the oscillation marks on the surface of solidified steel, which has undesirable effects on the quality of slabs. In order to reduce the oscillation marks by achieving soft contact of molten metal with the mold surface, alternating magnetic field is applied to the surface of molten metal. However, if the magnetic field strength becomes too strong, the melt flow induced by the magnetic field. causes the instability of the molten metal surface, which has also the bad influence on the slab quality. Therefore, it is very important to choose the optimal position of the inductor coil and the optimal level of electric power to minimize the surface defects. In the present work, as a first step toward the optimization problem of the process, numerical studies are performed to investigate the effects of coil position and the electric power level on the meniscus shape and the flow field. As numerical tools, the boundary integral equation method(BIEM) is used for the magnetic field analysis and the finite difference method (FDM) with orthogonal grid generation is used for the flow analysis.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.427-434
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• 2006

This study was performed to investigate the consumption and the preference of chungkukjang products among the middle school students. The subject were 538 middle school students(male 283, female 255) in $3^{th}$ grade, and were asked to fill out the questionnaire. The collected data were analyzed by SAS package. The result showed that most students knew about traditional chungkukjang(88.5%) and chungkukjang powder(68.2%), but only 43.5% and 29.4% of the respondents knew about raw chungkukjang and chungkukjang pill, respectively. When asked how often they eat chungkukjang products, traditional chungkukjang were taken often, but chungkukjang powder, raw chungkukjang and chungkukjang pill were shown to be taken relatively less. Over 60% of the students responded that they liked chungkukjang products, because of 'encourage by parents' and 'good for health', but there was no statistical difference by gender. When asked about the reasons for the dislike of the chungkukjang products, male students responded 'bad smell'of traditional chungkukjang, while female students 'eplied' not eating at home'. The students disliked the chungkukjang powder, chungkukjang pill and raw chungkukjang because of 'not knowing it.' These results showed that the social interest and support for the chungkukjang products were necessary and there was a need to advertise the chungkukjang products.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.5
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• pp.51-60
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• 2020

The paper examines the characteristics and causes of the expectation gap of audit and assurance services. The paper has conducted three surveys with three target groups. In the first survey, participants are auditors, users of audit reports are subject in the second survey and in the third survey, and students major in auditing are selected. The content of the survey aims to find out the differences in perception of the survey participants on two issues: (i) responsibilities of auditors for detection frauds, errors, protection of the enterprise's assets and financial scandals, and (ii) the role of audit and auditors in making investment decisions and investor's belief. The research carried out survey from March to September 2019 with 165 responds. The collected data was processed by statistical software SPSS, version 23, and Mann-Whitney U test was used to analyze the results of the audit expectation gap between the auditor group and the users of audit report group and between the student group and users of audit report group. The results showed that there exists an expectation gap in the responsibility of auditors for detection of all frauds, errors and protection enterprise's assets. Recommendations include strengthening audit standards, penalizing bad practices and ensuring auditor's independence.

• Journal of the Korea Safety Management & Science
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• v.18 no.3
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• pp.9-15
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• 2016

Currently the forest area is 6,370,000 hectare (ha) which occupies 63.7% in Korea. The forest has good functions such as production of forest products, conservation of national land, prevention of disasters, etc. However constructing houses near the forest area make bad situation like illegal waste incineration by resident. So research subject is forest fire caused by waste incineration place including facility. And this study was conducted about statistical analysis and research analysis of the 100 waste incineration places including facilities at the country town. Statistical analysis shows that March is 27% which percentage is the highest number of forest fire in 10 years' average. The number of forest fire caused by waste incineration is 45 which is the third highest number in the fire statistic. The distance between waste incineration place including facility and forest area is 30m, 40m and 50m. That 40m (36%) is the most common distance from forest area. The types of waste incineration are ground (62%), the temporary facility made with oil drum can (35%) and other made with steel sheet, concrete, etc. The result of this study is that government and local government must conduct the improvement measure to reduce illegal incineration such as waste pickup area made with rain and wind proof type installed near residence, expenses for waste treatment, enlightenment and training, etc. Also considering their age and income are needed for realistic improvement.

• Clean Technology
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• v.8 no.3
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• pp.129-139
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• 2002

This is the study for recycling waste foundry sand. Authors studied about main subject of grading of aggregate and three experimental items such as physical properties of waste foundry sand, optimum grading for concrete products of low water ratio, and quality variations of concrete products according to substitution proportion of fine aggregate as waste foundry sand. We were convinced of following results by experimental study. The first was that waste foundry sand was not fit as the aggregate for concrete because of bad qualities such as grading, unit weight, solid volume and passing 0.08 mm seive, so it is proper to composition using with other fine aggregetes. The second was that optimum grading is fineness modulus of 2.77 to 3.28 And the last is that optimum condition about substitution proportion as waste foundry sand is 10% fine aggregate.

• Korean Journal of Computational Design and Engineering
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• v.14 no.4
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• pp.242-253
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• 2009

Nowadays, manufacturing industry has been making its effort not only for productivity elevation but also for cost reduction in order to survive in the global market which is more and more challenging. In this paper, the method for planning of digital manufacturing system is proposed and door trim assembly system is determined as the subject of our research. First of all, the process sequence is generated based on the product analysis. And, the static and dynamic relationships between system components are represented using IDEF0 and UML model. The working time is estimated through the regression analysis based on MODAPTS method. According to the system configuration strategy, initial concept system layout is implemented 3D virtual environment. The problems caused by bad working motions are detected and modified through the ergonomic analysis using RULA method. According to proposed procedure, digital door trim assembly system is implemented in DLEMIA.

• Korean System Dynamics Review
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• v.6 no.1
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• pp.125-145
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• 2005

The Sihwaho Project got off to a bad start, which led to a series of mishaps and an imbalance of the whole project. The purpose of this study is to select the case of Sihwaho as a research subject, clean up the contamination caused by the ill planned project, develop suitable measures to stabilize the lake environment, and find the implications of similar development projects. For this, the authorshave conducted three simulations after studying the structural reasons for the failure of the Sihwaho Policy by identifying cause and effect relationships, pre-testing a number of policy measures for the current lake project, and presenting measures for solving the contamination problem at the lake. The simulations have shown us that filling the lake with seawater is inadequate to solve the problem and that we also have to make efforts to reduce the volume of wastes to the lake as well. The authorshave also analyzed the degree of difference between the simulation and survey results for scenario 1, in which we have studied how much seawater can reduce the contamination of the Sihwaho Lake without the effort to reduce the volume of wastes into the lake. The survey showed that most citizens and employees of the Ministry of Environment did not think it would be serious as the simulation results pointed out, and the employees of the Ministry of Environment were more optimistic about the situation than the public.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.2
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• pp.17-28
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• 2010

The considerable increase of the elderly with dementia is expected annually and when we think about the family members' and the patients' suffering, it could be painful. Above all things, it imposes heavy economic burdens on the family members that have patients who suffer from diseases of age like dementia or paralysis that caring them at home and also, it is not desirable for those old people in point of physical or environmental circumstances for medical care. Thus, it is needed urgently that the expansion of specified facilities and improvement of services for these old people. Under this present condition, it is the special feature that the subject of research is people/facilities that offer services, not the elderly with dementia-the main user of those facilities. This proposal aims to make a study of expansion and improvement the old people's welfare facilities by using remodeled closed Small and Midium Hospitals which are the bad effect of economic growth. Also, it can save money with re-using abolished buildings which is property of the nation and protect environment too. In this study, We examine the present conditions of old people's welfare institution, and research a factor of remodeling for welfare facilities. Then we will verify remodeling-possibility which is concrete and working by using the product of this study.