• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.42-49
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• 2001

This study was carried out to develop a fuzzy control technique of ventilation window for controlling a temperature in a greenhouse. To reduce the fuzzy variables, the inside air temperature shop was taken as one of fuzzy variables, because the inside air temperature variation of a greenhouse by ventilation at the same window aperture is affected by difference between inside and outside air temperature, outside wind speed and the wind direction. Therefore, the antecedent variables for fuzzy algorithm were used the control error and its slop, which was same value as the inside air temperature slop during the control period, and the conclusion variable was used the window aperture opening rate. Through the basic and applicative control experiment with the control period of 3 minutes the optimum ranges of fuzzy variables were decided. The control error and its slop were taken as 3 and 1.5 times compared with target error in steady state, and the window opening rate were taken as 30% of full size of the window aperture. To evaluate the developed fuzzy algorithm in which the optimized 19 rules of fuzzy production were used, the performances of fuzzy control and PID control were compared. The temperature control errors by the fuzzy control and PID control were lower than 1.3$^{\circ}C$ and 2.2$^{\circ}C$ respectively. The accumulated operating size of the window, the number of operating and the number of inverse operating for the fuzzy control were 0.4 times, 0.5 times and 0.3 times of those compared with the PID control. Therefore, the fuzzy control can operating the window more smooth and reduce the operating energy by 1/2 times of PID control.

• International Journal of Highway Engineering
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• v.16 no.1
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• pp.11-19
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• 2014

PURPOSES : The purpose of this article is to investigate the predicted life of jointed concrete pavement (JCP) with two variables effecting on axle load spectra (ALS). The first variable is different data acquisition methods whether using high-speed weigh-in-motion (HS-WIM) or not and the other one is spectra distribution due to overweight enforcement on main-lane of expressway using HS-WIM. METHODS : Three sets of ALS had been collected i) ALS provided by Korea Pavement Research Program (KPRP), which had been obtained without using HS-WIM ii) ALS collected by HS-WIM before the enforcement at Kimcheon and Seonsan site iii) ALS collected after the enforcement at the same sites. And all ALS had been classified into twelve vehicle classes and four axle types to compare each other. Among the vehicle classes, class 6, 7, 10 and 12 were selected as the major target for comparing each ALS because these were considered as the primary trucks with a high rate of overweight loading. In order to analyze the performance of JCP based on pavement life, fatigue crack and International Roughness Index (IRI) were predicted using road pavement design program developed by KPRP and each ALS with same annual average daily traffic (AADT) was applied to design slab thickness. RESULTS : Comparison ALS of KPRP with those of HS-WIM shows that the ALS of KPRP has a low percentage of heavy spectra such as 6~9 tonnes for single axle, 18~21 tonnes for tandem axle and 27~30 tonnes for tridem axle than other two ALS of HS-WIM in most vehicle classes and axle types. It means that ALS of KPRP was underestimated. And after the enforcement, percentage of heavy spectra close to 10 tonnes per an axle are lowered than before the enforcement by the effect of overweight enforcement because the spectra are related to overweight regulation. Prediction results of pavement life for each ALS present that the ALS of HS-WIM collected before the enforcement makes the pavement life short more than others. On the other hand, the ALS of KPRP causes the longest life under same thickness of slab. Thus, it is possible that actual performance life of JCP under the traffic like ALS of HS-WIM could be short than predicted life if the pavement was designed based on ALS provided by KPRP. CONCLUSIONS : It is necessary to choose more reliable and practical ALS when designing JCP because ALS can be fairly affected by acquisition methods. In addition, it is important to extend performance life of the pavement in service by controlling traffic load such as overweight enforcement.

• Korea journal of population studies
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• v.31 no.1
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• pp.55-73
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• 2008

This research explores the relationship between gender equity within family and second birth in Korea. For a factor analysis on the intention of having additional children for women with one child, I have used the data from the 2005 National Survey on Marriage and Fertility Trend" of the Korea Institute for Health and Social Affairs. Among 516 samples(year of 20-44), women planning to have second birth are 54.7%, and others have answered that they have no intention to have second birth. As a result, main causes affecting progressing to second birth seemed to be family planning on family cycle, such as controlling age gaps between first and second child, composing children genders as they wish etc. The variable of "gender equity between couples" in progressing to second birth are of significant only with married working women group. In case of married working women, more the husband's houseworking hours increase, the more prone to progress to second birth. However, in case of housewives, gender equity level, such as husband's housework hours or share of housework are not of significant influence in progressing to second birth. Not only working mothers but also housewives need the realization of gender equity within the family and the expansion of social support system for work-family life balance.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.489-496
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• 1997

In other to study relationship of anxiety and serum cholesterol in general population, we performed the interview survey and screening test for the Ju-am cohort and residents in controlling area at 1995. Among them, 622 people are selected for this analysis. The results were summarized as follows. 1. Anxiety and total serum cholesterol related each other in the group of anxiety. Correlation coefficient was 0.39(p<0.01). 2. According to the result of multiple regression that the total serum cholesterol regarded as the dependent variable, anxiety and total serum cholesterol were related each other positively in the group of anxiety(p<0.05). 3. As the symptoms of anxiety was dichotomized affective and somatic symptom. There was no relationship of 2 symptoms and total serum cholesterol in all subjects, but there was more relationship on the affective symptom than on the somatic symptom in the group of anxiety(p<0.05). The above results show that anxiety and total serum cholesterol related each other significantly in the anxiety group. And the relationship of psychological factors and serum cholesterol could be applied significantly in general population as well as in the special group.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.3
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• pp.145-153
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• 2005

I reviewed an ecological and environmental significance of microbial carbon respiration coupled to dis-similatory reduction of fe(III) to Fe(II) which is one of the major processes controlling mineralization of organic matter and behavior of metals and nutrients in various anaerobic environments. Relative significance of Fe(III) reduction in the mineralization of organic matter in diverse marine environments appeared to be extremely variable, ranging from negligible up to $100\%$. Cenerally, Fe(III) reduction dominated anaerobic car-bon mineralization when concentrations of reactive Fe(III) were higher, indicating that availability of reactive Fe(III) was a major factor determining the relative significance of Fe(III) reduction in anaerobic carbon mineralization. In anaerobic coastal sediments where $O_2$ supply is limited, tidal flushing, bioturbation and vegetation were most likely responsible for regulating the availability of Fe(III) for Fe(III) reducing bacteria (FeRB). Capabilities of FeRB in mineralization of organic matter and conversion of metals implied that FeRB may function as a useful eco-technological tool for the bioremediation of anoxic coastal environments contaminated by toxic organic and metal pollutants.

• Korean Journal of Social Welfare Studies
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• v.49 no.2
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• pp.233-256
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• 2018

The purpose of this study was to investigate the effects of social support on career maturity and self-reliance of inmates in a juvenile reformatory. This survey was administered to the adolescents in S juvenile reformatory, which represents juvenile reformatory across the nation. Statistical analysis were performed using SPSS 22.0 for 115 complete responses. Results are as follows: First, the effects of social support on career maturity was found to be statistically significant, $R^2=.411$, p<.001. That is, support by friends and religious program personnel remained a significant influence on career maturity, after controlling for sociodemographic variables. Second, the effects of social support on self-reliance was also found to be statistically significant, $R^2=.520$, p<.001. It was shown that the support of friends and family as dependent variables, had statistically significant effects on self-reliance. The results of this study suggest the need to expand programs that reinforce support by friends, a meaningful variable, along with the need to seek and link available resources within the local community in order to build social support systems. It is also necessary to establish education and related organizations to provide effective socail support.

• Management & Information Systems Review
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• v.38 no.3
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• pp.35-53
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• 2019

A standing auditor can perform the monitoring and control activities for the opportunistic behaviors of top manager. However, for this purpose she/he must have the independence from top manager. Thus, this study is designed to analyze the factors that influences the independence of standing auditor. The independence of standing auditor as dependent variable was measured in terms of school and company ties to top manager. The relationship between the shareholding of professional top manager and independence of standing auditor, and the moderating effects of the shareholdings of related-party, institutional investors, and foreign investors were examined by implementing multiple regression and conditional moderating effect analyses. The findings present a negative relationship between the shareholding of professional top managers and the independence of standing auditor. They also reveal a positive moderating effect of the shareholding of related-party on that relationship. On the other hand, the shareholdings of foreign and institutional investors did not significant change the relationship between the shareholding of professional top manager and the independence of standing auditor. The findings imply that professional manager might be able to lower the controlling mechanism by appointing a standing auditor having low independence. Related-party as an internal control mechanism might be beneficial to reduce this effect while institutional investors or foreign investors as an external control mechanisms might not. This is the first study that examine the antecedents of the independence of standing auditor in terms of the characteristics of ownership structure. It provides a guideline for selecting an effective standing auditor with the consideration for ownership structure.

• Journal of Digital Convergence
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• v.17 no.5
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• pp.1-10
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• 2019

The purpose of this study is to verify the effect of the compaction and virtue experienced by police officers in the organization on positive emotion and, second, to demonstrate the effect of positive emotion on the organization uniformity, which is subordinate variable. Third, we intend to verify the mediated effect of positive emotion in the relationship between compassion and organization uniformity, and fourthly, to demonstrate the coordination effect of collective self-esteem in the relationship between positive emotion and organization identicalness. Sampling of this study was conducted on 353 male and female police officers working at police stations belonging to the National Police Agency and used these samples for hypothesis testing. Studies have confirmed that the compaction and virtue experienced by police officers have a positive effect on positive emotion, and that positive emotion has a positive effect on the phenomenon of tissue co-ordination. And it has been shown that positive emotion plays a full role in the relationship between compassion, virtue and organizational co-ordination, and that positive emotion and collective self-esteem plays a controlling role in the relationship with organizational co-ordination. The theoretical implications of this study will contribute to creating a positive organizational culture by maintaining a strict hierarchical relationship and spreading the compaction and virtuous behavior to police organizations with high task stress.

• Journal of Korean Library and Information Science Society
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• v.52 no.2
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• pp.145-166
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• 2021

The study was aimed at verifying the effectiveness of Book-Coding reading education as a reader activity of older elementary school children at a time when high-dimensional thinking abilities were formed. To this end, 30 fifth-grade children of N Elementary School in N-si, Gyeonggi-do, comprised of 15 students from a reading education program using Book-Coding, and 15 students from a reading comprehension program, and applied the reading education program over a total of 12 sessions. The main results of the study are summarized as follows. First, when the effects of the convergence reading education program using Book-Coding on the logical thinking ability of the students in the upper grades in the elementary school were analyzed, all the six sub-factors of logical thinking ability, that is, conservation logic, proportional logic, variable controlling logic, probabilistic logic, correlational inference logic, and combinational logic, were proved to have statistically more meaningful difference than the group writing a book report. Second, the analysis result of the influence of the convergence reading education program using Book-Coding on the creativity of the students in the upper grades of the elementary school showed that all the 13 elements of curiosity, persistence, effectiveness, independence, adventurousness, openness, knowledge, imagination, originality, sensitivity, fluency, flexibility, and accuracy were statistically meaningfully different compared to the book report group. Third, when it was analyzed how the convergence reading education program using Book-Coding affected the creative personality of the elementary school students, all the six factors of curiosity, task commitment, independence, awareness of risk, and openness of thinking, and aesthetics were found out to have a statistically more meaningful difference than the group that wrote a book report.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.4
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• pp.239-267
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• 2022

In this study, the adolescents' perception of the Information Search Process(ISP); their anxiety and the need for intervention during the process were investigated based on Kuhlthau's ISP model, and the relationship among the factors was analyzed with structural equations. In addition, the effectiveness of scaffolding strategy to the experimental group during the class was verified. The main findings are as follows. First, as a result of exploring the anxiety felt by learners and the need for intervention in the information search process, it was found that the presentation stage had a significant effect on the anxiety, and the collection, presentation, and assessment stages had significant effects on the need for intervention. Second, as a result of controlling each variable to investigate the anxiety felt by learners and necessity of intervention in the information search process, it was confirmed that among the demographic variables, the difference between the first graders and the second ones was significant; and the difference in the metropolitan area was more significant than that in the Gangwon province. Third, as a result of paired t-test and covariance analysis on the control group and the experimental group, it was confirmed that the anxiety and need for intervention of the experimental group were statistically significantly reduced. The significance of this study lies in the point that it presents a practical basis for applying scaffolding strategies appropriate to information search process in the field of education.