• Journal of the Korea Safety Management & Science
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• v.25 no.1
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• pp.23-29
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• 2023

Among the Additive Manufacturing (AM) technologies, the Binder-Jetting printing technology is a method of spraying an adhesive on the surface of powder and laminate layer by layer. Recently, this technique has become a major issue in the production of large casting products such as ship-building, custom vehicles and so on. In this study, we performed research to make actual mold castings and increase mechanical property by using special sand and water-based binders. For use as a mold, it has a strength of more than 3MPa and permeability. Various experiments were carried out to obtain suitable them. The major process parameters were binder jetting volume, binder types, layer thickness and heat treatment condition. As a result of this study, the binder drop quantity was measured to be about 60 pico-liter, layer thickness was 100㎛ and the heat treatment condition was measured about 1,000℃ and compressive strength were measured to be more than 5MPa. The optimum condition of this experiment was established through actual casting of aluminum. The equipment used in this study was a Freeforms T400 model (SFS Co., Ltd.), and the printing area of 420 * 300 * 250mm and resolution of 600dpi can be realized.

• Korean Journal of Human Ecology
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• v.7 no.3
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• pp.59-71
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• 2004

The purpose of this study is to emboss the importance of safety education by recognizing the instructor's thoughts on safety and the prevention of safety accidents of early-childhood through the examination, analysis of the education site of safety at early-childhood education facilities. The subject of this were 120 early-childhood teachers in the Jeonbuk areas. The data were collected using questionaries and analyzed by the statistical methods of frequencies. ANOVA with SPSS pc program. The research questions were as follows; 1. What is the understanding of early-childhood teachers on safety recognition? 2. Is there a difference in the understanding of the teacher on safety and the management of the education curriculum on safety education that is being taught at early-childhood education facilities? The main results and solutions of this study were as follows: 1. In order for early-childhood teachers to teach safety education in early-childhood education facilities, they must join a safety mutual aid association or join an insurance policy to furnish an appropriate compensation system. Also, safety education must be systematically taught at a $social{\cdot}national$ level so that teachers and young children can have an understanding on safety under the support and concern of early-childhood education facilities and administration authorities. 2. Results on the comparison of the understanding of safety education and management of actual education of teachers on the actual conditions of the education curriculum of safety education show that although teachers are aware of most items of safety education but the actual education was not being taught. This means that although the teachers are aware of the importance of safety education, the actual education is not being taught.

• Water Engineering Research
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• v.5 no.1
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• pp.1-16
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• 2004

The purpose of this study is to understand the characteristics of hourly PET(Potential Evapo Transpiration) variation estimated using Penman ET model. The estimated PET using Penman model was compared with measured ET. For this study, two subwatersheds were selected, and fluxes, meteorological data and soil moisture data were measured during the summer and winter days. During the winter days, the aerodynamic term of Penman ET is much greater than that of energy term of Penman ET for dry soil condition. The opposite phenomena appeared fer wet soil condition. During the summer days, energy term is much more important factor for ET estimation compared with aerodynamic term regardless of soil moisture condition. Penman ET, measured ET, and energy term show the similar hourly variation pattern mainly because the influence of net radiation on the estimation of Penman ET is much more significant compared with other variables. Even though there are much more soil moisture in the soil during the wet days, the estimated hourly ET from Penman model and measured hourly ET have smaller values compared with those of dry days, indicating the effect of cloudy weather condition.

• Journal of the Korean Institute of Educational Facilities
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• v.16 no.4
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• pp.79-88
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• 2009

To enhance the administrational efficiency and for university facility and space management to be public, this research suggests a competent and an objective evaluation system and index. The study will assist national and university finances to contribute towards advanced education. Furthermore, figure out the space management condition of national university by utilizing the evaluation system, and through that suggesting efficient special management method. According to the result of this study, evaluation system for university facility can be widely divided into seven categories; system preparation, members conference, propriety of space allocation, propriety of management system, space use ratio, time control of space use, imposition index of surplus use. Based on these subdivisions, the space management category contains 19 evaluation items and the marking system allows perfect score of 100 points. In result of examining space management condition using the evaluation system, space management was well enforced in research focused university group where as in education centered university group, it shows relatively low enforcement. It also illustrated that efforts of evaluation items were required in categories of imposition index of surplus use and special use ratio in order for efficient space management.

• Journal of Korean Academy of Nursing
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• v.28 no.3
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• pp.695-704
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• 1998

This study aims for examines the actual physical symptom and stress in caregivers of patients with cerebrovascular disease. The data were collected by a survey conducted from August to September, 1997 which included 65 caregivers of cerebrovascular disease patients in 4 hospitals located in Seoul. The caregiver's stress was measured by Choi (1992)'s instrument and the actual physical symptoms were investigated. The data were analyzed using ANOVA, Scheffe test, Pearson correlation coefficient and stepwise multiple regression. The results were as follows : 1. The mean number of caregiver's physical symptom was 3.5. There were significantly higher number of physical symptom in women, those of who have a religious affiliation, those of who perceive their own health status perceived as bad, and those of who perceived their patients disease condition as serious than in their counterparts. Also, the number of caregiver's physical symptom was significantly higher in caregivers whose patients have a paralysis sypmtom and the disease onset as accident than in caregivers whose patients have no paralysis symptom and the disease onset as spontaneous. 2. The average of caregiver's stress was 57.9. The caregiver's stress was the highest in between the ages of 50 and 59. There were also significantly higher level of stress in women, those of who perceived the disease condition of their patients as serious than in their counterparts. 3. The most common caregiver's physical symptom was fatigue(87.7%). This was followed by insomnia(58.5%) and muscle pain(47.7%). 4. Caregiver's physical sypmtom was positively correlated with caregiver's stress and negatively correlated with patient's activity of daily life. 5. The most important vairable affecting the caregiver's physical symtom was patient's activity of daily life which accounted for 12.7% of the total variance in stepwise multiple regression analysis. The most important vairable affecting the caregiver's stress was the patient disease condition perceived by the caregiver that accounted for 12.1% of the total variance.

• International Commerce and Information Review
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• v.8 no.4
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• pp.159-175
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• 2006

This paper that explain exchange rate determination using Korea's economy data moment investigate whether each theory cause effect that is some on exchange rate showdown analyzing actual proof relation between foreign exchange fluctuation and financing part variance examine wish to. Because korea economic enters in the 1990s and the 2000s and the change is notable, foreign exchange fluctuation by such change is real condition that is changing. In this paper, I wish to enforce actual proof analysis if change such as him is grasped by form that is some about foreign exchange fluctuation. First, the second chapter investigates exchange rate decision theory that is used on actual proof interpretation, and executes actual proof Test in reply in subsequent the third chapter. And finally, the fourth chapter wishes to drive conclusion of this paper.

• Journal of radiological science and technology
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• v.5 no.1
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• pp.45-47
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• 1982

Authors carried out the research on the actual condition of intensifying screens in a certain hospital and obtained the results as follows: 1. High speed intensifying screens were 63.9% and medium typed screen had 36.1%. 2. Half the number of using screens(51.5%) were not clear in a period of used time. 3. 47.4% of same typed screens showed a remarkable difference(two times) in sensitivity.

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.647-652
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• 1994

This study was carried out to investigate the actual condition of canine herpesvirus(CHV) infection in Korea. A total of 338 serum samples were collected randomly from the breeding and companion dogs in the local areas in Korea. The serum samples were used to determine the actual condition of the canine herpesvirus infection in Korea using enzyme linked immunosorbent assay(ELISA). The mean prevalence of CHV infection in dogs was 37% and that of the breeding and companion dogs was 58% and 28%, respectively. The prevalence of CHV infection in Seoul, Kyung-gi, Chung Nam, Cheon Nam and Pusan was detected 23%, 28%, 18%, 28% and 70%, respectively. The prevalence of CHV infection in less and more than 6 months old dogs, and in male and female dogs was 26% and 40%, 42% and 33%, respectively. These results indicate that the incidence of CHV infection is high in Korea, especially breeding dogs and older dogs.

• Journal of the Korean Society of Safety
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• v.14 no.2
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• pp.140-147
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• 1999

Currently, the consumer pattern is directed to small quantity and high variety these days. World market is led by technological innovations and changes rapidly. To survive in this environment, the raising of small and medium enterprises is highly desirable. In the context of nationwide restructuring, competitive medium and small industries which are in good financial status should lead the nation's economy. But general ignorance of the safety issues could lead to a miss management of this industry in this field. In this study, actual condition and improvement of safety management are as follows; We have to 1) find out the factors which endangers this industry, and set a proper guideline for safety management. 2) encourage safety management of these industries by themselves, and advertise and provide technical support for using PC and internet. 3) set a higher standard of safety issue when accrediting a prospective medium and small industry, and have a firm control of this issue once accredited. 4) supply more governmental financial aids to terms of safety issues for medium and small industries.

• Journal of Korean Institute of Fire Investigation
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• v.8 no.1
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• pp.41-48
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• 2006

The purpose of this study is to identify the fire danger of the electric radiant heating system and check the way how to use it and the problems that could be possible through a actual case. We carry out an experiment to identify the possibility of the fire in the similar condition of the actual fire case. The results of this study are as follows. It is a possible condition to fire if the air blast of the electric radiant heating system is blocked by some combustible materials such as plastic bags continuously. A temperature sensor and a residual current device are necessary to disconnect the power source. It is also necessary to attach a notice in front of the electric radiant hearing system that shows users the fire danger to forbid the possible fire. Fires could be happened by internal defects of the electronic products. However, we can also find many external reasons to happen fires. Therefore, we need to check all reasons to make fires in the scene of a fire.