• Journal of Aerospace System Engineering
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• v.16 no.5
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• pp.62-69
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• 2022

EHA (Electro-Hydrostatic Actuator) is more energy efficiency than a centralized hydraulic system. In particular, the EHA used for aircraft has a redundant design in preparation for failure scenario. Also, due to the aircraft's internal space limitation, the actuator's length must be optimized. Therefore, a series configuration of double rod and single rod cylinder is advantageous. However, due to the asymmetry of the cross-sectional area of the piston, the force fighting phenomenon between the two cylinder areas occurs during redundant operation with a general control system. In this paper, the force fighting phenomenon of redundant EHA was simulated. A controller with load compensation and a force control-based position controller as a method to suppress its stimulation

• Journal of agricultural medicine and community health
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• v.18 no.2
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• pp.105-119
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• 1993

The purpose of this study was to evaluate the program for the control of acute respiratory infections(ARI) in children in a Korean rural area(Yonchon county). Evaluating the program, we focused on the pattern of prescription and appropriateness of antibiotics prescribed by the health personnel who had participated in the ARI Control Program. It was implemented at the primary health care setting in rural area, such as district hospital, health subcenters, and health posts. During six-months programme monitoring period, medical records were reviewed and collected data were analysed by the pediatrician, research coordinator of this study. The baseline data were collected from medical records of the same period(six months) of one year before the implementation of the ARI programme. The study results were as follow : 1. Common cold was the most prevalent disease(78.7%. 594 cases) among the all ARI cases (755 cases). The less frequent cases were bronchitis(11.9%), acute pharyngitis(5.2%), and pneumonia(1.8%). 2. Significant reduction in the use of antibiotics was observed after the programme implementation. Ninety three(15.7%) of 594 common cold cases were received antibiotics compared with 282(35.2%) of 802 in the baseline period. In the cases of bronchitis and acute pharyngitis, the reduction rates were 15.1% and 23.2% respectively compared to the baseline period. 3. Mean duration of antibiotics prescription was 1.81-1.75 days, similar to the baseline data. 4. The appropriateness rate of antibiotics prescriptions were 84.3%(common cold), 35.6% (bronchitis) and 28.2%(acute pharyngitis). In the case of pneumonia, the antibiotics prescription was compatible to the criteria developed. 5. Pediatrician prescribed antibiotics more appropriately for all cases than general practitioners in health sub-center, and nurse practitioners in health posts. 6. Antibiotics therapy was shown to be of no effect in the treatment of the all ARI cases. At the 5 and 10 days check-up of common cold cases after visits, proportion of improved patients were 58.3% in the antibiotics-used group and 51.4% in the control group. In the other cases of ARI, the patterns of response were similar to common cold. None of the differences in outcome between the antibiotics-used and control group was statistically significant. This ARI programme may have substantial a substantial impact on antibiotics use at the public health institutions(district hospital, health subcenters, health posts) which are of major domain for primary health care in Korean rural areas.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1879-1887
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• 2013

To investigate the level of genotoxicity over Bangkok atmosphere, $PM_{10}$ samples were collected at the Klongchan Housing Authority (KHA), Nonsree High School (NHS), Watsing High School (WHS), Electricity Generating Authority of Thailand (EGAT), Chokchai 4 Police Station (CPS), Dindaeng Housing Authority (DHA) and Badindecha High School (BHS). For all monitoring stations, each sample covered a period of 24 hours taken at a normal weekday every month from January-December 2006 forming a database of 84 individual air samples (i.e. $12{\times}7=84$). Atmospheric concentrations of low molecular weight PAHs (i.e. phenanthrene, anthracene, pyrene and fluoranthene) were measured in $PM_{10}$ at seven observatory sites operated by the pollution control department of Thailand (PCD). The mutagenicity of extracts of the samples was compared in Salmonella according to standard Ames test method. The dependence of the effects on sampling time and on sampling location was investigated with the aid of a calculation of mutagenic index (MI). This MI was used to estimate the increase in mutagenicity above background levels (i.e. negative control) at the seven monitoring sites in urban area of Bangkok due to anthropogenic emissions within that area. Applications of the AMES method showed that the average MI of $PM_{10}$ collected at all sampling sites were $1.37{\pm}0.10$ (TA98; +S9), $1.24{\pm}0.08$ (TA98; -S9), $1.45{\pm}0.10$ (TA100; +S9) and $1.30{\pm}0.09$ (TA100; -S9) with relatively less variations. Analytical results reconfirm that the particulate PAH concentrations measured at PCD air quality monitoring stations are moderately low in comparison with previous results observed in other countries. In addition, the concept of incremental lifetime particulate matter exposure (ILPE) was employed to investigate the potential risks of exposure to particulate PAHs in Bangkok atmosphere.

• Journal of the Korean Institute of Educational Facilities
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• v.22 no.2
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• pp.3-13
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• 2015

The policy of the Ministry of education through the social awareness and issues are being changed. Accordingly, in response to the school building which also has to be changed. This study is Low-floor(1~2 floor) for high accessibility, important management and a lot of locomotion. This study is analysis by floor of newly established schools in Chungbuk. Facility and space on the possible low-floor situated are classified administrative zone, health zone, student support + local exchange zone, STEAM(creativity, personality) supporting zone. The administrative area includes administration office, principal's office and board rooms. The administrative zone is located against schoolyard. Because it is possible visual control of schoolyard. also it controls visitor access so it is placed near main entrance. Health zone is located near a special class, counseling center and wee class for emergency situation. and is located near schoolyard for visual control. Student support + local exchange area includes library and computer lab, audio-visual room, auditorium or gymnasium. It put more emphasis resident welfare, culture and education. So it opens for local residents. It is located center of few stories or near entrance. STEAM(creativity, personality) supports science lab, art room, family room. It is possible such a theory class, experience class and indoor and outdoor class. It is located few floors. This study is used as a reference for school building projects planing.

• Journal of Korean Academy of Nursing
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• v.39 no.5
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• pp.720-730
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• 2009

Purpose: The purpose of this study was to test the effects of tailored diabetic education on blood glucose control and self-care for patients with type 2 diabetes on insulin therapy. Methods: The participants were 60 patients (experimental group: 30, control group: 30) with type 2 diabetes on insulin therapy. The patients were being seen at a university hospital in Seoul, Korea. Group diabetic education and tailored diabetic education were given to the experiment group while group diabetic education only was given to the control group. Data were collected before and three months after the education. $X^2$ test, t-test, and ANCOVA were used to analyze the data. Results: No significant differences in postprandial (PP2hrs) glucose and HbA1c levels were found between the two groups. Participants in the experiment group showed statistically significant differences in the area of self-glucose test, management of insulin injection, and life style change compared to those in the control group. Conclusion: The results indicate that tailored education for patients with diabetes on insulin therapy improve self-glucose test, management of insulin injection, and life style. Therefore it is suggested that tailored education can be applied in diabetic education to improve self-care.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.2
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• pp.117-125
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• 2015

Quantitative risk assessment (QRA) of railway is to create a variety of scenario and to quantify the degree of risk by a result of the product of accident frequency and accident. Quantitative risk Assessment is affected by various factors such as tunnel specifications, characteristics of the fire, and relation of smoke control and evacuation direction. So in this study, it is conducted that how the way of smoke control and the relation of smoke control and evacuation direction affect quantitative risk assessment with variables (the tunnel length (2, 3, 4, 5, 6 km) and the slope (5, 15, 25‰)). As the result, in a train fire at the double track tunnel (Area = $97m^2$), it is most efficient to evacuate to the opposite direction of smoke control regardless of the location of train in train fire. In addition, under the same condition, index risk in mechanical ventilation up to 1/10.

• Parasites, Hosts and Diseases
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• v.47 no.4
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• pp.323-335
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• 2009

A successful experience of lymphatic filariasis control in the Republic of Korea is briefly reviewed. Filariasis in the Republic of Korea was exclusively caused by infection with Brugia malayi. Over the past several decades from the 1950s to 2006, many investigators exerted their efforts to detection, treatment, and follow-up of filariasis patients in endemic areas, and to control filariasis. Mass, combined with selective, treatments with diethylcarbamazine to microfilaria positive persons had been made them free from microfilaremia and contributed to significant decrease of the microfilarial density in previously endemic areas. Significant decrease of microfilaria positive cases in an area influenced eventually to the endemicity of filariasis in the relevant locality. Together with remarkable economic growth followed by improvement of environmental and personal hygiene and living standards, the factors stated above have contributed to blocking the transmission cycle of B. malayi and led to disappearance of this mosquito-borne ancient disease in the Republic of Korea.

• Journal of Hydrogen and New Energy
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• v.10 no.1
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• pp.19-26
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• 1999

The effectiveness of a double-tube heat exchanger has been investigated experimentally. This problem is of particular interest in the design of the heat exchanger in a hydrogen liquefaction system. Temperature, pressure, and mass flow rate for hydrogen were measured both in inner tube and in annulus of a double-tube heat exchanger. The effectiveness could be evaluated from the measured temperature and mass flow rate. It is found that the effectiveness increases with an increase in the heat transfer area of a double-tube heat exchanger and with a decrease of the heat capacity ratio. But the increase rate of the effectiveness decreased with a decrease of the heat capacity ratio. Therefore, it is presented that a criterion for selecting the heat exchanger length and heat capacity ratio to obtain the effectiveness required in a hydrogen liquefaction system.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.277-289
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• 2012

This study was conducted to find the nutrition status and the effects of nutrition education by comparing the condition of the subjects before and after the education among elementary students attending a community child center(CCC). The subjects of the study were 70 elementary school students in CCC in Donggu, Ulsan as a control group compared to other 87 elementary students in the same age and the same area. The result were as follows. The students in CCC showed higher rate of skipping breakfasts and less rate of having snacks, compared with control students. Also they showed lower scores of both nutrition knowledge and dietary belief. The CCC group had higher rate of skipping meals, especially on weekends(72.9%), and showed less nutrient intakes than the control group. After the nutrition education, nutrition knowledge and dietary beliefs of the nutrition group showed better results but no difference in their dietary attitudes. The education did not make significant differences in the rate of skipping meals and in the nutrient intakes. Considering all the results above, an adequate plan for providing meals is required as well as a nutrition education for improvement of the poor nutrition condition of children in CCC.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.4
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• pp.200-207
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• 2018

In recent, KEPCO (Korea Electric Power Corporation) faced difficulties of the DCC (distribution control center) due to the increase of field equipment and operational cost, and aging of operating staffs. In response to these changes in the DCC, KEPCO is trying to change the organization and system of the DCC. In this paper, we present a new attempt to change organization and structure of distribution control center, which was implemented by KEPCO recently. This paper is divided into three major parts. First, to examine the adequacy of the divided basis of current DCCs based on the quantity of installed electrical equipment, we analyzed the correlation between the operational history of the DCCs and the number of equipment. Through the analysis, we confirmed that there is little relationship between the number of equipment and actual workload. Second, we conducted visits and questionnaire surveys of all the DCCs to identify factors affecting the actual workload of distribution operators and then summarized the results. Third, based on this survey, a general formula for analyzing the workload of a DCC was derived, and each DCC's average annual total workload, day/night workload, and required number of personnel were calculated. Through this study, we proposed a more realistic management method of DCCs that can overcome the division criteria based on equipment quantity.