• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.241-245
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• 2007

국내 홍수빈도 분포의 매개변수 추정에서 지점추정(at-site estimate) 방법은 유량 자료의 부족으로 발생하는 표본오차(sampling error)가 크기 때문에 충분한 유량 자료를 보유한 지점에 한하여 제한적으로 사용되고 있다. 대안으로 동질성을 가진 유역의 유량 자료를 모아 지역 매개변수를 추정하는 지수홍수법(Index Flood Method)이 제안되기도 하였으나, 이질성이 큰 우리나라의 유역특성 때문에 적용이 쉽지 않다. Stedinger와 Tasker가 1986년 제안한 GLS(Generalized Least Square) 기법은 유역을 동질지역으로 구분할 필요가 없으며 지점들간의 상관관계와 이분산성을 고려할 수 있어, 국내 홍수빈도 해석을 위해서 꼭 도입해야할 기법으로 생각된다. 본 연구에서는 기존의 GLS 기법의 단점을 보완한 Bayesian-GLS 기법을 이용하여, 국내 대유역에 골고루 위치하며 댐의 영향을 받지 않는 31개 지점의 연최대 일유량 시계열의 L-변동계수(L-moment coefficient variation)와 L-왜도계수(L-moment coefficient skewness)를 추정할 수 있는 회귀모형을 제안하였다. 위 회귀모형을 구성하기 위한 유역특성으로는 유역면적, 유역경사, 유역평균강우 등을 사용하였다. Bayesian-GLS (B-GLS) 적용 결과를 OLS(Ordinary Least Square) 및 Bayesian-GLS 기법에서 지점간의 상관관계를 고려하지 않는 Bayesian-WLS(Weighted Least Square)와 비교 평가하여 그 우수성을 입증하였다. 따라서 본 연구에서 제안된 B-GLS에 의한 지역회귀모형은 국내의 미계측유역이나 또는 관측 길이가 짧은 계측유역의 홍수빈도분석을 위해 매우 유용할 것으로 기대된다.년 홍수 피해가 발생하고 있지만, 다른 한편 인구밀도가 높고 1인당 가용 수자원이 상대적으로 적기 때문에 국지적 물 부족 문제를 경험하고 있다. 최근 국제적으로도 농업용수의 물 낭비 최소화와 절약 노력 및 타 분야 물 수요 증대에 대한 대응 능력 제고가 매우 중요한 과제로 부각되고 있다. 2006년 3월 멕시코에서 개최된 제4차 세계 물 포럼에서 국제 강 네트워크는 "세계 물 위기의 주범은 농경지", "농민들은 모든 물 위기 논의에서 핵심"이라고 주장하고, 전 프랑스 총리 미셀 로카르는 "...관개시설에 큰 문제점이 있고 덜 조방적 농업을 하도록 농민들을 설득해야 한다. 이는 전체 농경법을 바꾸는 문제..."(segye.com, 2006. 3. 19)라고 주장하는 등 세계 물 문제 해결을 위해서는 농업용수의 효율적 이용 관리가 중요함을 강조하였다. 본 연구는 이러한 국내외 여건 및 정책 환경 변화에 적극적으로 대처하고 물 분쟁에 따른 갈등해소 전략 수립과 효율적인 물 배분 및 이용을 위한 기초연구로서 농업용수 수리권과 관련된 법 및 제도를 분석하였다.. 삼요소의 시용 시험결과 그 적량은 10a당 질소 10kg, 인산 5kg, 및 가리 6kg 정도였으며 질소는 8kg 이상의 경우에는 분시할수록 비효가 높았으며 특히 벼의 후기 중점시비에 의하여 1수영화수와 결실율의 증대가 크게 이루어졌다. 3. 파종기와 파종량에 관한 시험결과는 공시품종선단의 파종적기는 4월 25일부터 5월 10일경까지 인데 이 기간중 일찍 파종하는 경우에 파종적량은 10a당 약 8${\ell}$이고 늦은 경우에는 12${\ell}$ 정도였다. 여기서 늦게 파종한 경우 감수의 가장 큰 원인은 1수영화수가 적어지기 때문이었다. 4. 건답직파에 대한 담수상태로 관수를 시작하는 적기는 파종후

• Journal of Digital Convergence
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• v.12 no.10
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• pp.121-134
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• 2014

This study investigated the stock market reaction to the announcement of conversion to holding company and its influence on the market value and corporate governance before and after the event. Generally, it is known that the conversion to holding company strengthens corporate governance because of diversification effects. Accordingly, it is expected that holding companies have a significantly positive influence on the short and long term stock value and improve firm performance. The results are as follows. First, companies have significantly positive short-term abnormal returns for a day. It confirms the stock market reaction hypothesis. Second, it is found that corporate governance is improved in two ways, protection of stock holders' right and distribution of corporate income in the year after converting to holding companies. However, the degree of business concentration appears to be decreased but the result is statistically insignificant after the conversion. Third, there is no significant positive relation between market performance and both protection of stock holders' right and distribution of corporate income. Thus, the results do not adequately support the hypothesis between corporate transparency and market performance.

• Journal of the Korean Society for information Management
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• v.26 no.1
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• pp.7-34
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• 2009

The purpose of this study is to investigate the use of information resources of the humanities scholars in Korea and suggest the strategic planning of academic library and information services to serve their needs. To collect data, a mail survey was conducted during the period of November 2007 through January 2008. Out of 799 humanities scholars sampled from 25 universities, 132 responded with the completion rate of 16%. Major findings in this study are as follows: First, the majority of the humanities scholars distribute their time equally to research and education, and conduct independent research. Second, they still largely depend on print resources, including scholarly journals, books, and manuscripts for getting information, while using some online information resource mostly in text such as electronic documents and journals. They expect that the frequency of using such print resources would not decline much, but the use of online resources could definitely increase in the next five years. Some variances in the behavior were observed among the groups of scholars according to their research experiences. It is suggested that academic libraries (1) conduct more active outreach, (2) prioritize between traditional and electronic resources, (3) plan information literacy education for traditional resources.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.121-126
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• 1998

This study is to examine the energy budget of Hexagrammos agrammus in the natural habitat, based on the von Bertalanffy's growth model using food consumption and growth data of the fish. The fish were collected at the coasts of Tongbaek Island in Pusan and Shinsu Island in Samchonpo, Korea. The standard energy budget model was adopted for this study and the model has the components of toed consumption (C), production (G), assimilation (A), absorption ($A_b$), catabolism (R), excreta (U) and feces (F). These components were expressed as mass unit, not as calorie unit as usual. Both the mass and the proportion of each component varied with age of the fish, The mass of annual excreta declined as the fish became older, while those of the other components increased with the age. The relationship between mean weight (W) and annual absorption ($A_b$) was a non-linear one with the equation of $A_b=4.592W^{0.666}$, while that between mean weight (W) and annual catabolism (R) was linear as R=0.007+0.567W. On the other hand, the annual food consumption (C) showed linear relations both with annual assimilation (A) and annual catabolism (R) as A= -7.026+0.061C and R=-20.749+0.048C, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.137-144
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• 2019

The purpose of this study is to investigate the relationship between the perception of dying with dignity and the quality of life based on the opinions of the Korean populations. The participants were selected using a stratified proportional allocation method and 1,000 adults aged between 19 and 74 years from 17 municipalities and provinces in Korea. The questionnaire consisted of 2 demographic items; 26 items on the quality of life scale; and 57 items on the perception of dying with dignity. The statistical methods used included frequency analyses, independent sample t-tests, and correlation analyses. The results showed that the quality of life was highest for the social life quality item, and that the participants who had experienced a death in the family were more likely to have statistically lower quality of life in physical, psychological, environmental, and social areas. In terms of the participants' perception on dying with dignity, the score for death preparation was the highest; specifically, the score for psychological/economic burden reduction was the highest. The quality of life of the participants showed a positive correlation in all aspects of the perception of dying with dignity: physical symptoms and control, death preparation, death environment, family and social relations, hospital treatment, psychological dignity, and spirituality. Other studies conducted with middle-aged populations showed that their quality of life was higher when they perceived the acceptance of death is important and were willing to participate in death preparation education. Therefore, in order to improve the quality of life and have a positive influence on the participants, educational programs on death preparation and dying with dignity considering all the areas of the perception of dying with dignity should be provided.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.509-518
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• 2002

The purpose of this study was to evaluate the bonding of compomer to deciduous dentin which is known to have been developed to improve the weak properties of glass ionomer cement and composite resin. 120 sound primary molars were used for the shear bond strength test and another 24 for the scanning electron microscopic evaluation. Each material was ailed into polyethylene mold attached to exposed dentinal surface($3{\times}4mm$ in diameter) of sample blocks. Shearbond strength was measured using Universal testing machine and data were analyzed statistically with Oneway-ANOVA and Scheffe test. Scanning electron microscopic observation was performed in order to evaluate the pattern of distribution and penetration of resin tags and hybrid layer. Compomer groups(II-V) showed significantly higher bond strength values than glass ionomer group(I)(p<.05). Etching-compomer groups(III, V) showed the significantly higher bond strength than non-etching compomer groups(II, IV)(p<.05), but slightly lower values than composite resin group(VI) with no statistically significant difference(p>.05). No significantly different bond strength was found between compomer groups of different bonding system(p>.05). Scanning electron micrographs showed more irregular distribution of short and thin resin tags in non-etching compomer groups(II, IV) whereas the more regular and intimate distribution of long and thick tags in etching compomer groups(III, V) and composite resin group(VI). The evaluation of hybrid layer also showed more regular formation of thicker layer in etching compomer groups(III, V). Based on the results of present study, the use of compomer as an esthetic restorative material for primary molars might be justified.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.3
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• pp.419-430
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• 2000

The purpose of this study was to compare the microleakage pattern of preventive resin restoration using conventional composite resin and flowable composite resin that recently developed. 60 sound premolar teeth were allocated to three groups. Flowable composite resin was used for the experimental groups(Group I and II) and conventional resin for the control group(Group III). After composite filling and sealant application, all teeth were thermocycled and evaluated for microleakage under light microscope. Additionally, a variety of voids formed inside restorations were also evaluated. Data were analyzed statistically using Kruskal-Wallis test and/or Mann-Whitney U-test. The results of the present study were as follows. 1. Microleakage found in all samples was only limited to the interface of restoration margin and enamel. 2. The flowable composite resin groups (Group I, II) generally showed less microleakage than control groups (conventional preventive resin restoration) (p<0.05) 3. Various types of voids were observed in most specimens. Especially, there was a tendency for more and larger voids to be found in group I, II than group III (p<0.05).

• The Journal of Korean Academy of Sensory Integration
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• v.15 no.2
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• pp.46-65
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• 2017

Objective : The purpose of this research is to find clinical effects of application of weighted vest during task-oriented training focused on gross motor performance and balance abilities of children with spastic diplegia. Methods : 34 subjects were divided by simple random sampling into two groups; experimental group (male : 9, female : 8, average age : 8.12) and placebo group (male : 9, female : 9, average age : 7.53). Both two groups underwent to 40 minute intervention, twice a week for 12 weeks. The intervention was task-oriented training focused on facilitating closed kinematic chain and multi-joint functional movement pattern. During the training, the experimental group received loaded-resistance weighted vest and placebo group also received weighted vest but without loaded-resistance. Participants in both groups underwent 8 to 10 reps of the task-oriented training and there were 3 minutes break time between tasks. There were pre-test of gross motor performance and balance abilities, and two times of post-tests were performed upon 6 weeks and 12 weeks after the intervention completed. And in final, an additional follow-up test was performed 12 weeks after the evaluation was finished in order to find any difference between the two groups over time. Results : There was significant difference in Gross Motor Performance Measure (GMPM) between two groups. It is found that average score of the experimental group increased more than the placebo group after 6 weeks and 12 weeks intervention (p<.05). There was significant difference in Pediatric Berg's Balance Scale (PBS) between two groups. It is found that average score of the experimental group increased more than the placebo group after 6 weeks and 12 weeks intervention (p<.05). Conclusion : Based on the results in this study, it is proposed that application of weighted vest into task-oriented training to facilitating closed kinematic chain and multi-joint movement can improve gross motor performance and balance abilities of children with cerebral palsy.

• Journal of Intelligence and Information Systems
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• v.23 no.3
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• pp.155-175
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• 2017

As social data become into the spotlight, mainstream web search engines provide data indicate how many people searched specific keyword: Web Search Traffic data. Web search traffic information is collection of each crowd that search for specific keyword. In a various area, web search traffic can be used as one of useful variables that represent the attention of common users on specific interests. A lot of studies uses web search traffic data to nowcast or forecast social phenomenon such as epidemic prediction, consumer pattern analysis, product life cycle, financial invest modeling and so on. Also web search traffic data have begun to be applied to predict tourist inbound. Proper demand prediction is needed because tourism is high value-added industry as increasing employment and foreign exchange. Among those tourists, especially Chinese tourists: Youke is continuously growing nowadays, Youke has been largest tourist inbound of Korea tourism for many years and tourism profits per one Youke as well. It is important that research into proper demand prediction approaches of Youke in both public and private sector. Accurate tourism demands prediction is important to efficient decision making in a limited resource. This study suggests improved model that reflects latest issue of society by presented the attention from group of individual. Trip abroad is generally high-involvement activity so that potential tourists likely deep into searching for information about their own trip. Web search traffic data presents tourists' attention in the process of preparation their journey instantaneous and dynamic way. So that this study attempted select key words that potential Chinese tourists likely searched out internet. Baidu-Chinese biggest web search engine that share over 80%- provides users with accessing to web search traffic data. Qualitative interview with potential tourists helps us to understand the information search behavior before a trip and identify the keywords for this study. Selected key words of web search traffic are categorized by how much directly related to "Korean Tourism" in a three levels. Classifying categories helps to find out which keyword can explain Youke inbound demands from close one to far one as distance of category. Web search traffic data of each key words gathered by web crawler developed to crawling web search data onto Baidu Index. Using automatically gathered variable data, linear model is designed by multiple regression analysis for suitable for operational application of decision and policy making because of easiness to explanation about variables' effective relationship. After regression linear models have composed, comparing with model composed traditional variables and model additional input web search traffic data variables to traditional model has conducted by significance and R squared. after comparing performance of models, final model is composed. Final regression model has improved explanation and advantage of real-time immediacy and convenience than traditional model. Furthermore, this study demonstrates system intuitively visualized to general use -Youke Mining solution has several functions of tourist decision making including embed final regression model. Youke Mining solution has algorithm based on data science and well-designed simple interface. In the end this research suggests three significant meanings on theoretical, practical and political aspects. Theoretically, Youke Mining system and the model in this research are the first step on the Youke inbound prediction using interactive and instant variable: web search traffic information represents tourists' attention while prepare their trip. Baidu web search traffic data has more than 80% of web search engine market. Practically, Baidu data could represent attention of the potential tourists who prepare their own tour as real-time. Finally, in political way, designed Chinese tourist demands prediction model based on web search traffic can be used to tourism decision making for efficient managing of resource and optimizing opportunity for successful policy.