• Journal of the Korean Society of Hazard Mitigation
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• 제7권4호
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• pp.67-74
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• 2007

Rational method has been widely used to calculate peak runoff drainage design or small watershed because of simplicity and convenience. Runoff coefficient(C) is the most important parameter in the rational method which varies according to rainfall intensity, return period, rainfall duration time and soil characteristics. In practice, constant which is value of C in rational formula has been used from the table, originally based on ASCE. These table value does not consider the upper conditions of the depending factors, hence peak runoff calculation could be in correct. Therefore to calculate C in this paper we have devised an improved formula, considering relationship with rainfall duration, return period and CN of NRCS method. This formula is considered to be more reliable and helpful to the hydrologists and engineers to predict correct peak runoff.

• Journal of the Korean Society of Marine Environment & Safety
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• 제19권5호
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• pp.511-517
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• 2013

Maritime police recognize that the organizational culture of various acting as a member of the organization. Also, marine policing and security activities to determine the number of build. The overall culture of maritime police who share the organization sub-culture may take place. Maritime police organizational culture and a variety of types of group culture, hierarchical culture, development culture, rational culture examined the differences in perceptions. Maritime police aware of the general results of the analysis are as follows; First, the maritime police officers of the age group of 20 was the highest recognition in hierarchy culture and rational culture. Second, the maritime police officers of the rank of captain was the highest recognition in development culture and rational culture. Third, differences in the perception of organizational culture by recruitment analysis show the difference in cultural groups showed, in particular, the special recruitment group of police officers, and maritime police culture can be seen tend to appear low.

• Journal of the Korean Society of Hazard Mitigation
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• 제10권3호
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• pp.109-118
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• 2010

This study quantified the flood reduction effect of small stormwater detention facilities by the NRCS curve number. The modified rational equation was used to calculate the inflow volume into the detention facilities. The NRCS curve number in the cases w/ and w/o storage facility was calculated with respect to the rainfall characteristics(rainfall frequency, duration) and the size of storage facilities. Finally, diagrams showing the curve number reduction rate versus the size of storage facility were developed. The diagrams can be used to evaluate the flood reduction effect of storage facility reasonably and efficiently when estimating the optimal location and size of storage facility. The results based on the methodology propsed in this study were also compared with those of previous study for their validation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권2호
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• pp.626-642
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• 2018

Recently, a number of studies have drawn attention to purchasing online game items. Most of the studies are based on the assumption that consumers behave rationally. Accordingly, TRA- or value-based approaches have been mainly employed to understand the online purchases of game items. However, the purchasing behavior of consumers involves not only making rational decisions, but also making irrational decisions. Hence, their purchase behavior is affected by propensities for conspicuous consumption, impulsive consumption, and habitual consumption. Playing games can be highly addictive, and players often display such addictive behaviors. Our study explored both the rational and irrational factors in purchase behavior to understand how they are associated with purchasing game items. A total of 366 pieces of data were collected from Korean online game users through a survey. Regression analyses of the collected data showed that the behavior of buying game items was influenced not only by the intention to purchase which is a rational factor in consumption, but also by such irrational factors as habit, impulse, and ostentation which should be further emphasized in future studies.

• Journal of Preventive Medicine and Public Health
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• 제24권1호
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• pp.16-28
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• 1991

Service diversification is recognized as an important strategy against turbulent environmental change. This study is designed to find out the trend of service diversification in Korean health care organizations and also to identify factors associated with the degree of service diversification. Data were collected from 69 hospitals out of 71 hospitals with over 300 beds. Important findings are summarized below. 1. Types of diversification are closely related to hospital size. Large hospitals have a tendency to provide sophisticated services requiring specialized skills and equipment, while small hospital have concentrated their efforts on health screening programs. 2. The more competitive and bigger hospitals are, the greater number of services that provide. Also, hospitals operating rational management information systems provide more services. Contrary to the expectation hospitals with a low performance during last 3 years showed more service diversification. 3. A trend of more diversification was observed in hospitals whose chief executive officer used a prospector strategy. 4. A multiple regression analysis revealed that bed size, competitive environment, degree of rational management, and the growth pattern were significantly associated with the service diversification.

• Journal of Digital Contents Society
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• 제10권2호
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• pp.189-198
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• 2009

In this paper, we propose a method to improve the performance of orthogonal frequency division multiplexing (OFDM) receivers by using oversampling the received signals. Demodulation of the received OFDM signals is to detect the amplitude and phase components of the subcarriers. From the oversampled OFDM signals, we can get redundant informations in frequency domain for the data, which are different in phase but the same in amplitude. By using these properties, we can obtain signal to noise ratio (SNR) gain by the oversampling ratio compared to the receivers which sampled with symbol rate. In this paper, we propose oversampled receivers whose oversampling ratio is expanded from integer to general rational number. Through computer simulations, we show the validity of the proposed methods by comparing the performance of the receivers with nonideal band-limiting filters.

• The Korean Journal of Emergency Medical Services
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• 제13권3호
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• pp.107-120
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• 2009

Purpose : The purpose of this study was to investigate the influence of organizational culture on job satisfaction of fire officials. Method : The subjects of this study were 251 fire officials in Gongju and Choengju province and Daejeon City. Data were collected using self-administering questionnaire from February 20 to March 20 in 2006. Collected data were analyzed using SPSS 14.0 program. Real number, percentage, mean and standard deviation were calculated, and t-test, ANOVA, Pearson correlation coefficient, multiple regression were analyzed. Result : The results of this study were as follows : 1. The job satisfaction was found to be significant positive correlations with full organizational culture(r = .595, p = .000). 2. The job satisfaction was found to be in significant positive with rational goal culture, open system culture and human relation culture. 3. How organizational culture affects the job satisfactions was as follows; 25.2% of core values of manpower, 6.3% of rational goal culture, and 4.9% of job initiative. Conclusion : Enhancing the job satisfaction of fire officials would improve personalized factors and changes rational goal culture.

• Journal of the Chungcheong Mathematical Society
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• 제22권3호
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• pp.299-307
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• 2009

We count the isomorphism classes of elliptic curves over finite fields $\mathbb{F}_{3^{n}}$ and list a representative of each isomorphism class. Also we give the number of rational points for each supersingular elliptic curve over $\mathbb{F}_{3^{n}}$.

• Communications of the Korean Mathematical Society
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• 제20권2호
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• pp.259-273
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• 2005

In this paper we determine all subfields with genus one of cyclotomic function fields over rational function fields explicitly.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.441-444
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• 1999

The crack width of concrete structures subjected to shrinkage depend on a great number of parameters whose effects are restrain condition, the number and spacing of crack and the amounts of reinforcements. Through suitable reinforcement it is possible to make the individual cracks exceedigly small. This paper is to present the amount of reasonable reinforcement for crack control through a rational analysis of forces occuring in significantly restrained concrete structures due to the shrinkage. Also the analysis results from this paper are compared with the provisions for shrinkage and temperture reinforcement in the KCI concrete strucural design code.