• Journal of the Korean Institute of Intelligent Systems
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• v.3 no.2
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• pp.18-35
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• 1993

The water level control system of the steam generator in a pressurized water reactor and its control problems are analysed. In this work the stable control strategy during the low power operation and transient states is studied. To solve the problem, a fuzzy logic control method is applied as a basic algorithm of the controller. The control algorithm is based on the operator's knowledges and the experiences of manual operation for water level control at the compact nuclear simulator set up in Korea Atomic Energy Research Institute. From a viewpoint of the system realization, the control variables and rules are established considering simpler tuning and the input-output relation. The control strategy includes the dynamic tuning method and employs a substitutional information using the bypass valve opening instead of incorrectly measured signal at the low flow rate as the fuzzy variable of the flow rate during the pressure control mode of the steam generator. It also involves the switching algorithm between the control valves to suppress the perturbation of water level. The simulation results show that both of the fine control action at the small level error and the quick response at the large level error can be obtained and that the performance of the controller is improved.

• Cartoon and Animation Studies
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• s.45
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• pp.451-477
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• 2016

The changes in media environments have impacted on the ways in which knowledges are formed and transmitted and therefore the relevance of the traditional school subjects have been increasingly questioned. In this context, the discourses of the reformation of the 21st century schooling have focused on convergence education and media literacy education. Therefore, it is worth paying attention to the fact that the practices of transdisciplinary integrated curriculum focusing on digital media content are grown voluntarily in schools. This research is a case study of a convergence educational project that was initiated by a middle school teacher who designed and implemented a unique program of the transdisciplinary class of Korean focusing on reading webtoons with the linked program of a 'Book Club Activity' that was a part of 'Creative Experiential Activitites'. Based on the analysis of the documents, participatory observation of a main event and the interview with the teacher, this article discusses how the webtoon-focused convergence education project might have achieved meaningful connections between a subject-focused learning and a creative experiences-focused learning; between in and out of school learning spaces; between the real and imaginative worlds; and between the boundaries of the popular culture and the arts. The main finding of the research can be summarized as follows: Firstly, webtoon as the subject of the study can be an effective medium of transdisciplinary integrated curriculum. Secondly, the convergence project based on webtoons can create meaningful learning spaces in and out of school environments in terms of creating more learner-participatory learning culture as well as connecting students' everyday lives, popular arts and their learning about culture. Another important finding of this research is the rediscovery of the teacher's role in terms of mediating the voices of students as readers in the process of constructing and implementing the integrated curriculum.

• Childhood Kidney Diseases
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• v.4 no.2
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• pp.154-160
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• 2000

The pathogenesis of IgA nephropathy and acute poststreptococcal glomerulonephritis is not fully understood. In the past, acute poststreptococcal glumerulonephritis was the most common cause of gross hematuria in children, but now IgA nephropathy is the most common one. We experienced two cases of acute poststreptococcal glomerulonephritis superimposing to IgA nephropathy in boys Case 1 had upper respiratory infection before elevation of anti-streptolysin O, generalized edema, gross hematuria and proteinuria. The complement levels were normal. Electron microscopic findings of renal biopsy at ten days after onset showed a few big subepithelial 'humps' and localized heavy subendothelial and mesangial deposits. Immunofluoroscopic findings revealed predominant IgA deposition in the mesangium. The electron microscopic findings were diagnostic of acute poststreptococcal glomerulonephritis On the other hand, immunoflorescence microscopic findings were compatible to IgA nephropathy. In case 2, the renal biopsy which was done 2 years after onset showed only finding of IgA nephropathy. To our knowledges, there has been kw reports of acute poststreptococcal glomerulonephritis superimposing to IgA nephropathy which was confirmed by renal biopsy. We report two cases of acute poststreptococcal glomerulonephritis superimposing: to IgA nephropathy with a brief review of the literatures.

• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.101-117
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• 1973

Socio-medical survey was carried out on six hundred and thirty Korean households in the cities of Tokyo, Osaka, Kyoto, and Nagoya in Japan from Nov. 1972 to Dec. 1972, and following results were obtained. 1. Age distribution of households showed the highest occurence in the group of 40 to 49 years of age in the both sexes. Families with five members showed highest occurence, and the average number of familial members was 5.7 persons per one household. 2. More than half of the householders were some independent enterprisers rather than to be the employees and most of the household had one familial member engaged in more or less liberal profession. 3. 19.4% of households moved into these cities from 1941 to 1945. 4. 40.5% of all the households had their own houses. The possession rate of one's own house was higher in the households which had long period of residence in Japan. 5. 83.5% of all households had various medical insurances. And the 6.2% of the household which had no insurance stated that the reason for not being affiliated was 'because to be the foreigner'. Household of shorter dwelling period had less tendency to be affiliated to the various insurances. 6. In 41.3% of all the households, average medical expenditure amounted to 1000-5000 Yen per month. And only 25.6% of household stated that they do not worry about the medical expenditure for the futures. 7. 66.3% of households were consulting to medical doctors for their sickness, such as toothache, severe coughing, profuse sputum, children's fever and stomach pain etc. 8. 59.4% of households were using the facilities of health center services. The health center service was used mainly for individual health service rather than the environmental aspect. And 19.8% of households were not aware of health center activities. 9. It was found that 23.5% of households received the screening test of the tuberculosis and adult diseases. Especially, the rate of screening test of the adult diseases showed as following ; stomach cancer, 8.9% ; hypertension, 7.9% ; diabetes mellitus, 2.1% ; and uterus cancer, 1.6%. 10. Birth control was carried out in 17.3% of households but not in 52.5%. The chief reason of birth control was 'because of poor maternal health' (40.0%) or 'should not be done' (5.4%). 11. Most of them are obtaining the knowledges and informations on family plannings. public nuisance problems and nutritions etc. by means of the mass communications, while those no preventing diseases and the environmental hygiene through the administrative organizations.

• Journal of the Korean Wood Science and Technology
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• v.37 no.1
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• pp.87-93
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• 2009

Properties and chemical bonding of wood charcoal were investigated to understand the chemistry occurring in wood carbonization. From the pH changes of wood charcoal, it is revealed that it becomes acidic to weakly basic for charcoal carbonized at about $300^{\circ}C$, whereas it turns to basic at higher carbonization temperature higher than $600^{\circ}C$. Also, the ratio of carbon atoms in the charcoal was increased with increasing the carbonization temperature, while those of oxygen and hydrogen atoms. This tendency was significant when the carbonization temperature was increased up to $600^{\circ}C$ and the ratio changes of the atoms became stable at above $600^{\circ}C$. In the changes of chemical bonding, the ratio of C-C bonding was increased and those of C-O-H and C-O-R bonding was decreased significantly. It is considered that bondings connected to oxygen atoms tends to be broken, and the ratio of C-C bonding increased. Consequently, it is expected that this change may causes occurrence of new functional groups. In addition to that, it seems to be that the chemical bondings undergo the partial decomposition, formation, and recombination steps, Because ratio of C=O bonding tended to be increased or decreased by increasing the carbonization temperature. This understanding of chemical bond changes in charcoal can be a compensative consideration on the knowledges made only by physical parameters in the properties of micro-pore which has limited to explain the phenomenon. Also, it is considered that this can be treated as a basic knowledge for upgrading and development of use of wood charcoal.

• Fire Science and Engineering
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• v.30 no.3
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• pp.73-78
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• 2016

The Installation, Maintence, and Safety Control of Fire-fighting Systems Act of South Korea regulates that over 30-storey high-rise buildings including underground spaces should vitally perform the Performance-based Design to minimize property damage and personal injury as a fire risk assessment in advance. Therefore a PBD designer such as a fire safety professional engineer evaluate occupant's life safety by a scientific methodology. In order to evaluate the life safety, fire safety designers calculate the Required Safety Egress Time (RSET) which does not have the legal criteria regarding the standard method of calculation yet. So this way has been showing different results depending upon the designer's choice, knowledges and experiences. In this study, RSET calculation methods by six designers respectively were analysed from the thirteen reports of real performance based design projects conducted in Busan for a last five years. In particular, the Response Time calculation methods which have the most powerful effect for figuring the RSET are compared with the other designer's to deduce an error value.

• Journal of Science Education
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• v.34 no.2
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• pp.246-259
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• 2010

The purpose of this study was to investigate pre-service biology teachers' perception of the evolution. This study was to compare the views of pre-service biology teachers with no religion with those of christian preservice teachers. Subjects were 77 pre-service biology teachers who enrolled in an university and graduate school of education located in Seoul. The instrument of this study was a questionnaire which consisted of 14 items on 2 domains: the nature of science, the origins of human beings. The key results are as follows. Most pre-service teachers showed highly understanding of the characteristics of science. However pre-service biology teachers still possessed naive views on the distinction of law and theory. In terms of the methods of science, many of the pre-service biology teachers considered scientific theories to progress through the accumulation of observation and experiments or through changes and modifications in existing theories. Compared with the pre-service teachers with no religion, christian pre-service teachers had conflicting views and misconceptions about the origins of human beings. The factors of religion were found to be one of the important barriers which prevent them from understanding the origins of human beings. The results suggested that the education program for pre-service biology teachers integrating the concepts and development process of the scientific knowledges should be effective for understanding the nature of science. For pre-service biology teachers, It is important to understand conflicting views of the christian pre-service teachers who understand creationism as a science.

• Journal of Korean Home Economics Education Association
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• v.15 no.2
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• pp.55-66
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• 2003

In Korea home economics in the secondary school level was only taught to girls until 1995. So. home economics education only for girls was criticized to sexist education by the feminists. According to the 6th revision of curriculum. home economics has been taught to girls and boys. But some of curriculum developers raises another questions on home economics education. They argue that home economics is a subject which prepares students for the demand of their day-to-day lives. but they can manage their lives well without school learning. The purpose of this study is to explore the educational values of home economics in secondary education from the gender-sensitive approach. For this study, a literature survey on the nature of home economic education in secondary education and the content analysis on 12 secondary school textbooks of Home Economics were employed. The results are as follows : First, the educational values of home economics education should not be underestimated. The aims of home economics education is to help students grew into a independent person by managing their daily lives. The home is charged with fostering a side of our life which we might call Personal, private. intimate and nurturing. The management of the home needs good skills and attitudes. and many knowledges on the child rearing, family relation, marriage, love and sex, which can not be successfully acquired without school learning. And home economics education for boys and girls can help break down the barriers between the sexes because it can change the attitudes of students regarding the private sphere. which is traditionally where women have worked. Second. most of contents of Home Economics were composed of the women-oriented contents. There was a trend still describing that domestic labor mainly be carried out by mother. And the ideas that only the family consisting of two parents and their children is normal were founded. Finally directions of development of the Home Economics Education are suggested.

• Journal of Radiation Protection and Research
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• v.30 no.2
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• pp.91-97
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• 2005

Bayesian methodology is appropriated for use in PRA because subjective knowledges as well as objective data are applied to assessment. In this study, radiological risk based on Bayesian methodology is assessed for the loss of source in field radiography. The exposure scenario for the lost source presented in U.S. NRC is reconstructed by considering the domestic situation and Bayes theorem is applied to updating of failure probabilities of safety functions. In case of updating of failure probabilities, it shows that 5 % Bayes credible intervals using Jeffreys prior distribution are lower than ones using vague prior distribution. It is noted that Jeffreys prior distribution is appropriated in risk assessment for systems having very low failure probabilities. And, it shows that the mean of the expected annual dose for the public based on Bayesian methodology is higher than the dose based on classical methodology because the means of the updated probabilities are higher than classical probabilities. The database for radiological risk assessment are sparse in domestic. It summarizes that Bayesian methodology can be applied as an useful alternative lot risk assessment and the study on risk assessment will be contributed to risk-informed regulation in the field of radiation safety.

• Journal of The Korean Association For Science Education
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• v.21 no.1
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• pp.22-29
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• 2001

The purpose of this study is to investigate the effects of lessons adopting portfolio assessment regarding feedback on elementary school student's scientific knowledges, inquiry abilities and their perceptions of it. For this study, two classes of 5th grade elementary school in suburb were selected. As an experimental group, one class was selected to apply the lessons adopting portfolio assessment regarding feedback, and the other class as a control group was selected to apply the lessons adopting portfolio assessment without feedback. The investigator taught and assessed both group students. The results showed a significant difference in scientific knowledge between the experimental group and the control group (p<.05). More detailed analysis of scientific knowledge found that the feedback effect was statistically positive in the memory and the understanding domain, but there was no effect in the application domain. No statistical difference was identified in inquiry abilities. The results of the questionnaire on the perceptions of portfolio assessment showed that students of the experimental group had higher positive responses on the 'perception about the effects of lesson' and on the 'perception in scientific attitudes' than the control group. However, the control group students had higher positive responses on the 'perception about self-evaluate of their own portfolio' and the 'perception about need of feedback' than the experimental group.