• Journal of Environmental Science International
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• v.18 no.6
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• pp.603-608
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• 2009

Activated sludge sewage treatment processes are difficult to be controlled because of their complex and nonlinear behaviour, however, the control of the dissolved oxygen level in the reactors plays an important role in the operation of the facility. For this reason, this study is designed to present a system which accurately measures DO, MLSS, pH and ORP in the aeration tank to alleviate situations above and provide the automatization of a sewage treatment plant (STP) using new DO control system. The automatic control systems must be guaranteed the accuracy. Therefore, the proposed automatic DO control system in this study could be commercial applications in the aeration tanks by means of operating cost analysis and user-friendly for operation and maintenance. We could get accurate data from the lab tank which has water quality checker because there was no vortex and air bubble during the measurement process. Improvement of confidence in the lab tank enabled effective and automatic operation of sewage treatment plants so that operation costs and manpower could be saved. If this result is put in place in every sewage treatment plant nationwide for practical purposes, it is estimated to cost 18.5 million dollars in installing the lab tank and to save 9.8 million dollars in management cost a year, except for cost saved by automation.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.263-268
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• 2009

The current focus of domestic car industry is moving from technological development to reducing greenhouse gas. This study investigates and measures the HVAC system and indoor air condition of highway buses, which is conducted to develop a HVAC system using natural energy in the future. The measurements show that thermal balance is not fulfilled because heating sources are randomly placed, and relative humidity is in the 20 percent range both in HVAC and non-HVAC systems, which is far below 40%, or the highest thermal comfort level. CO2 concentration was found to be an average of 1500 ppm, but not more than 2522 ppm with 15 persons on board, and with 29 persons on board, an average of 2053 ppm, but not more than 3066 ppm, both of which far exceed allowed CO2 concentration level, or 1000 ppm. Generally, highway buses drop by rest stops and open doors for 15 to 20 minutes for getting in fresh air. But its air improvement effect is temporary, and it exacerbates indoor air condition.

• Journal of Korean Academy of Nursing
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• v.36 no.2
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• pp.321-329
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• 2006

Purpose: The purpose of this study was to determine the effects of music therpy on anxiety and depression in patients undergoing hemodialysis. Method: The study was designed using a nonequivalent control group pretest-posttest design. The subjects consisted of 36 patients (Experimental group: 18, Control group: 18) who received hemodialysis in three hospitals located in Seoul. The measures were a Music Preference Questionnaire (MPQ), anxiety measurement, and depression measurement. Data was collected from December 26, 2004 to April 2, 2005 through questionnaires. The collected data was analyzed by the SPSS 10.0 program. Result: The first hypothesis that patients undergoing hemodialysis who received music therapy would have less anxiety than patients undergoing hemodialysis who did not receive music therapy was supported(F=8.05, p=.008). The second hypothesis that patient undergoing hemodialysis who received music therapy would have less depression than patients undergoing hemodialysis who did not receive music therapy was supported(F=11.86, p=.002). Conclusion: The results of this study suggest that music therapy may be applied as a method of nursing intervention contributing to the improvement of quality life by reducing their anxiety and depression of patients undergoing hemodialysis.

• Journal of the Korean Institute of Navigation
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• v.17 no.2
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• pp.1-27
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• 1993

As the education of maritime college has a characteristics of seafaring professional institutions, the potential benefit following from the employment of seafarers would put substantial impact on it. The socio-economic position of seafaring occupations has been deteriorated considerably with changes of ship's auto-mation, specialisation and low cost operation management of shipping companies through severe internatio-nal competitions. The quality and number of applicants for the maritime college has declined and most students have no hopes for the study of seafaring subjects which followed bewildering in their college days. However, the demands for seafarers are fairly large from the viewpoint of national maritime industry. The maritime institutions should not only meet these demands but also revitalise students by reforming the educational contents. The contents should be influenced by the social approach to educational needs in particular maritime shore-oriented subjects. The maritime education is no more restricted to the sea, it covers the land based world of the maritime industry as well. The new contents will lead the maritime educated students to the shore-based occupa-tions after finishing their seafaring if they want to. This may not only make ways to the maritime educa-tion fruitable, but also the students have a zeal and hope for the subjects taught.

• Korean Journal of Social Welfare
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• v.46
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• pp.236-262
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• 2001

This discovery-oriented study explored 31 social workers' perceptions of discrepancies between explicit and implicit rules in their work places that are supposed to affect the quality of social work services, and identified eight categories of dilemmas: (a) confused accountability or purpose, (b) ambiguous principle, (c) improper authority, (d) confused role of social workers, (e) conflict between ideal and reality, (f) confused work ethics, (g) confused boundary of workers' rights, and (h) binds. These eight categories revealed the real philosophy and purposes of social work agencies, work ethics and values prevalent among social work agencies, agencies' orientation toward clients, and the conditions of social support from the society in large. Instead of searching for discrete variables as separately responsible for inefficient social work services, this approach probed malfunctioning implicit rules in a holistic context to see if inefficient or ineffective provision of social work services is a logical response to a much larger and deeper nexus. Insight into discrepant rules does not solely ensure the improvement of social work practice in the field, particularly if their identification is simply used as another opportunity to blame and avoid self-responsibility. However, such discrepancies between implicit and explicit rules are real enough to the staff workers and agency administrators that they may want to begin the dialogue of contradictory rules as a way of sanctioning discussion of previously forbidden topics. This study provided the ground-work for the dialogue.

• Child Health Nursing Research
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• v.23 no.4
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• pp.440-448
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• 2017

Purpose: The purpose of this study was to investigate the effects of oral health education on oral health knowledge, oral health behavior, and oral hygiene status of children from North Korea. Methods: Participants were 32 North Korean children defectors (15 in the education group, 17 in the control group). The oral health education program, including theoretical training and toothbrush training, was done once a week for 4 weeks. Effects of the education program were assessed for oral health knowledge, oral health behavior, and oral hygiene status at pretest, 0, and 4 weeks after the intervention. Data were analyzed using repeated measures ANCOVA with the SAS program. Results: Children in the education group showed increased oral health knowledge and behavior over time compared to the control group and an improvement in oral hygiene status including significantly decreased S-PHP and Snyder test for oral micro-organism. Conclusion: Results indicate that oral health education is effective in improving oral health knowledge, oral health behavior and oral hygiene status. These improvements could lead to a better quality of life for North Korean children defectors.

• Journal of the Korea Safety Management & Science
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• v.19 no.3
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• pp.35-42
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• 2017

Process Hazard Analysis(PHA) have been performed for a risk management of process (petrochemical) industry for nearly 50 years. There are many PHA methods for application in the process industry, Hazop Study method has been recognized as a good method used typically in most of phase of process plant. And also there was inconvenient opinion that Hazop Study is too resource (man power, time etc.) consuming comparing its result performance (a quality of recommendations) for a good operating and existing plant. In this study, two types of PHA method - checklist and K-PSR - were performed respectively for a new para-xylene(PX)plant and 30 year old PX plant. Past history and experience of incident, operation, maintenance and so on are very important in PHA by those two methods. The higher effectiveness were realized in PHA by a checklist and K-PSR Method than prior Hazop study. And also some suggestions including PHA cycle determination, RBPS application, Follow-up plan of PHA result etc. were proposed about PHA improvement measures for a best risk management.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.1
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• pp.89-97
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• 2007

Simple regression models for pollutants load estimation of paddy developed by the Ministry of Environment in 1995 were tested with the data (T-N, T-P, $COD_{Mn}$, and SS) collected from Yeongsan and Seomjin river watersheds, and improvement measures were suggested. Overall, the simulated values showed a great difference from the measured values except for T-P according to the statistical analyses (RMSE, root mean square error; RMAE, root mean absolute error; RB, relative bias; EI, efficiency index). Such difference was assumed due to the fact that the models use only hydrologic factors (quantity factor) associated with precipitation and run-off as input parameters, but do not consider other factors which are likely to affect pollutant concentration (quality factor) including days after fertilization. In addition, in terms of accessibility of the models, some parameters in the models such as run-off depth and run-off amount which can not be obtained from the weather database but should be collected by on-site measurements need to be replaced with other variables.

• Journal of Korean Academy of Nursing
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• v.48 no.5
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• pp.506-520
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• 2018

Purpose: To compare the effects of the Interaction Model of Client Health Behavior (IMCHB)-based oral health program (OHP) and walking exercise program (WEP) on oral health behaviors, periodontal disease, physical activity, and psychological indicators (depression, stress, and quality of life) in pregnant women. Methods: A nonequivalent control group pretest-posttest design was adopted to compare the effects of a 12-week OHP and WEP on pregnant women (n=65). Pregnant women were randomly assigned to the oral health group (OHG; n=23), walking exercise group (WEG; n=21), or control group (CG; n=21). Data were analyzed by the ${\chi}^2-test$, Fisher's exact test, Scheffe test, and repeated measures ANOVA, using the Statistical Package for the Social Sciences for Windows (version 21.0). Results: The OHG and WEG showed significant improvements in oral health behaviors, periodontal disease, and psychological indicators as compared to the CG. The WEG showed significant improvement in physical activity as compared to the OHG and CG. Conclusion: These findings indicate that the IMCHB-based OHP and WEP were effective in improving periodontal disease, physical activity, and psychological indicators. However, further studies are needed to identify the positive effects of the OHP and WEP on birth outcomes.

• Journal of the Korea Institute of Building Construction
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• v.8 no.5
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• pp.93-99
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• 2008

The environment draws attention in the global community and a growing number of Koreans have interest in improving the quality of life, the importance of house environment has attracted the attention of the public. Against this backdrop, constructors have unveiled environmentally -friendly projects. However, they failed to establish people-oriented environment by being occupied with maximizing profitability through the improvement of brand image and caused sick house syndrome that has recently made controversy. In this regard, the study analyzed the mechanism of discharge of TVOC, one of the sick house syndrome-causing materials, that affects IAQ and its characteristics and examined the effect that granodiorite has on reduction of the discharge of TVOC in order to minimize damage. Experimental sample consisted of interior finishing materials frequently used in ceiling, wall and floor and adhesives used at a time of construction, and the TVOC of building materials was measured through the use of septum bottle unlike In the existing chamber method. Measures to counter the sick house syndrome were suggested by reducing the possible damage from the stage of selection of building material and by figuring out the effect that the granodiorite has on reduction of the discharge of TVOC.