• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.5
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• pp.527-537
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• 2014

In 2013, NGII(National Geographic Information Institute) has developed and provided the KNGeoid13(Korean National Geoid Model 2013) to support the fundamental computation of GNSS-derived orthometric height. In this study, the adjusted ellipsoidal height, the sum of geoidal height and height by the leveling, is applied to calculate the GNSS-derived orthometric height without the local bias, based on GNSS static surveying and KNGeoid13. The mean of errors in GNSS-derived orthometric heights could be verified with the leveling data, which was actually less than 0.5 cm with using the adjusted ellipsoidal heights, but 3 cm by calculating differences between ellipsoidal heights and geoidal heights. By analyze the accuracy of GNSS-derived orthometric height depending on the duration of observation, we could realized 95% of data shows less than 4 cm accuracy, when the GNSS survey conducting for 4 hours spread over two days, but while the case of GNSS survey conducting for 4 hours and 2 hours respectively, resulted in 95% of data less than 5cm level of accuracy. Also, if the ambiguity is fixed, less than 10cm of accuracy could be obtained at 95% of data for only 30 minutes GNSS survey over a day. Following the study, we expected that the height determination by GNSS and geoid models can be used in the public benchmark surveying.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1295-1299
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• 2006

횡월류위어는 홍수 피해 경감을 위해 계획되는 방수로나 저류지의 유입부에 주로 사용된다. 따라서 이러한 횡월류위어를 통해 방수로나 저류지로 월류되는 월류량을 정확히 예측하는 것은 이러한 시설의 홍수 피해 경감 능력을 예측하는데 있어 매우 중요하다. 횡월류위어를 통해 흐르는 흐름은 매우 복잡하기 때문에 일반적으로 이러한 흐름을 분석하는 것은 매우 어렵다. 따라서 대부분의 횡월류위어 유량계수 공식은 De Marchi의 해석해와 다양한 실험 자료에 근거하여 제시되고 있다. 따라서 지금까지 횡월류위어 유량계수에 대하여 많은 공식이 제안되어 왔지만, 대부분의 공식이 유사한 형태를 가지고 있으며, 횡월류위어의 상류에서의 프루드수$(Fr_1)$를 제일 중요한 설계 인자로 고려하고 있다. 그러나 최근 횡월류위어에 대한 연구가 점차 발전됨에 따라 횡월류위어 상류에서의 프루드수 외에도 위어높이와 횡월류위어 상류 수심의 비(h/y), 그리고 횡월류위어의 길이와 본류 폭의 비(L/B) 등이 고려되고 있다. 그 중에서 L/B 의 효과는 점차 중요하게 고려되고 있다. 그러나 대부분의 연구자들이 사용한 실험 장비들은 상 대적으로 높은 L/B 조건을 가지는데 반하여, 현재 국내에서 계획되고 있는 천변저류지 등에 설계된 횡월류위어의 설계 범위는 대체로 $1/10{\sim}1/200$이므로 기존 연구자들의 실험 범위와 매우 다르다고 할 수 있다. 따라서 본 연구에서는 상대적으로 폭이 넓은 실험 수로를 이용하여 횡월류예연위어의 유량 계수에 대한 실험을 수행하였다. 지금까지의 실험 결과에 의하면 동일한 실험 조건에 대해서 기존 연구자들에 의해서 제안된 공식으로 계산한 유량계수 보다 측정된 자료를 이용하여 계산한 유량계수의 값이 상대적으로 더 큰 것 으로 나타났다. 통해 배수될 때 암석이 머금고 있는 물로 인해 추가적으로 발생하는 중력은 다른 재료가 가지지 못한 화산석의 또 다른 장점이라 할 수 있다.서는 자료변환 및 가공이 필요하다. 즉, 각 상습침수지구에 필요한 지형도는 국립지리원에서 제작된 1:5,000 수치지형도가 있으나 이는 자료가 방대하고 상습침수지구에 필요하지 않은 자료들을 많이 포함하고 있으므로 상습침수지구의 데이터를 인터넷을 통해 서비스하기 위해서는 많은 불필요한 레이어의 삭제, 서비스 속도를 고려한 데이터의 일반화작업, 지도의 축소.확대 등 자료제공 방식에 따른 작업 그리고 가시성을 고려한 심볼 및 색채 디자인 등의 작업이 수반되어야 하며, 이들을 고려한 인터넷용 GIS기본도를 신규 제작한다. 상습침수지구와 관련된 각종 GIS데이타와 각 기관이 보유하고 있는 공공정보 가운데 공간정보와 연계되어야 하는 자료를 인터넷 GIS를 이용하여 효율적으로 관리하기 위해서는 단계별 구축전략이 필요하다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 상습침수구역관련 정보를 검색, 처리 및 분석할 수 있는 상습침수 구역 종합정보화 시스템을 구축토록 하였다.N, 항목에서 보 상류가 높게 나타났으나, 철거되지 않은 검전보나 안양대교보에 비해 그 차이가 크지 않은 것으로 나타났다.의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는

• Journal of the Korean Regional Science Association
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• v.34 no.3
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• pp.55-68
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• 2018

This paper aims to analyze the changes of the population distribution of metropolitan area by the development of the new town-type innovative city, focusing on the case of the Daegu Innovative City. Using dataset in the survey of population trend and the migration statistics microdata provided by the Statistics Korea, we decomposed population changes of Daegu and surrounding regions into natural increase and social increases(net migration). As a result of the analysis, Dong-gu, where the Daegu Innovation City is located, experienced population growth due to its increase of net migration, whereas the total population in Daegu been decreasing continuously between 2007 and 2016. In particular, the occurrence of high net migration to Dong-gu in 2014 showed a pattern consistent with the completion of the Daegu Innovative City development and the relocation of government institutions from the Seoul metro area. As a result of analyzing the migration to Dong-gu, the population moved from the Seoul metro area was 6.9% of the total, while the population moving from the other 7 gu-gun areas in Daegu (35.8%) and the surrounding regions (8.2%) were significantly high. In particular, the migration to Dong-gu were from neighboring areas, such as Suseong-gu, Buk-gu and Gyeongsan-si. Therefore, the development of the new town-type innovative city could accelerate toward sprawling urban structure.

• Industry Promotion Research
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• v.6 no.4
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• pp.23-30
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• 2021

This study is a study on the satisfaction of the living conditions of the residents of Chungcheongnam-do, and the analysis data was based on the results of the Chungcheongnam-do social survey conducted in 2020 by Statistics Korea. The results of the analysis on the satisfaction of the living conditions of the residents of Chungnam Province are summarized as follows. The level of satisfaction with the quality of life of the living environment, which is a personal characteristic, was 5.92 out of 10 for the degree of satisfaction with one's life, and 6.28 out of 10 for the overall value of the work one is doing. The overall life satisfaction of the region (city and gun) was analyzed as 5.81 out of 10, indicating that the satisfaction of Chungnam residents was more than average. In addition, satisfaction with the residential housing environment was analyzed with the highest frequency and ratio of 43.5%, with 226 people being slightly satisfied. Satisfaction with facility use was also slightly higher in 231 people, showing 44.5% response rate, and slightly higher in women than in men. This study is meaningful in that it provides basic data such as policy implications for improving the quality of life by grasping the social interests related to the quality of life and the subjective consciousness of the people of Chungnam.

• Journal of the Korean Society for information Management
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• v.38 no.3
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• pp.311-334
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• 2021

The purpose of this study is to present the theoretical basis and quantified objective standards for the establishment of collection management policy. The study results are summarized as follows. Most of the study books were in the form of periodicals as a steady seller. Most of the steady sellers were textbooks which published periodically. As a modern novel, a steady seller was able to confirm the phenomenon of dependence on a specific author. Bestsellers were investigated to be influenced by publishers and authors. Books of publishers that publish comics and children's textbooks had a significant correlation with the selection of bestsellers. The average number of recommended books borrowed per recommended book was 14,871. The average number of loans per book selected as a bestseller was 53,531. Based on the loan data, about 80-82% of all top-tier loans were covered by 90%, and about 27-29% of all top-ranked loans were covered by 50%. This shows that the Pareto Principle can be firmly applied to public library lending patterns. Loans in the field of literature accounted for 50.6% of the total loans. Among literature, Korean literature accounted for 51.3% of the total. The natural sciences were generating more loans with a relatively small pool of literature compared to other subject fields.

• Journal of Navigation and Port Research
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• v.43 no.1
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• pp.72-78
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• 2019

The second-hand ship market provides immediate access to the freight market for shipping investors. When introducing second-hand vessels, the precise estimate of the price is crucial to the decision-making process because it directly affects the burden of capital cost to investors in the future. Previous studies on the second-hand market have mainly focused on the market efficiency. The number of papers on the estimation of second-hand vessel values is very limited. This study proposes an artificial neural network model that has not been attempted in previous studies. Six factors, freight, new-building price, orderbook, scrap price, age and vessel size, that affect the second-hand ship price were identified through literature review. The employed data is 366 real trading records of Panamax second-hand vessels reported to Clarkson between January 2016 and December 2018. Statistical filtering was carried out through correlation analysis and stepwise regression analysis, and three parameters, which are freight, age and size, were selected. Ten-fold cross validation was used to estimate the hyper-parameters of the artificial neural network model. The result of this study confirmed that the performance of the artificial neural network model is better than that of simple stepwise regression analysis. The application of the statistical verification process and artificial neural network model differentiates this paper from others. In addition, it is expected that a scientific model that satisfies both statistical rationality and accuracy of the results will make a contribution to real-life practices.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.39-46
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• 2016

The history of Social service is above 10 years. Owing to corresponding to the user's needs social services sector is expanding. And, to deal with them, the social delivery systems has been changed. Traditional social welfare delivery system is provided by public facilities and private facilities. On the other hand, Social Services is made up of the traditional social welfare delivery system and new delivery system which is composed of profit organizations and non-profit organizations. Considering this, Study attempted to compare the performance evaluation of supply type-profit and non-profit social service organizations. Performance evaluation method was applied to net income, except for expenditure in total revenue. Net income difference between profit organization non-profit organization was assessed by T-test. We conclude that the two population means are different at the 0.05 significance level. Looking in detail, the non-profit organizations were found to be higher than the non-profit organizations, labor costs, operating costs, facility cost and consumable costs, but part of the business expense costs, the non-profit organizations was higher than the profit organizations.

• Journal of the Korean Society for Railway
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• v.20 no.1
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• pp.120-127
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• 2017

The South Korean rail authority is constructing a nationwide tourism belt by developing new rail tour routes in an effort to combine local tourism resources with rail service and to create value in regional areas. As massive financial resources are required to develop and operate such tourist trains, governing authorities are required to examine the feasibility of this project as a sound business model and to assess the public benefit and profitability of the project. In this study, the economic feasibility of the tourist trains was assessed with the contingent valuation method (CVM). According to an estimation of the willingness to pay of potential tour train passengers, the surveyed subjects were willing to pay fares that were higher than prices currently published at the time of this study, thereby demonstrating that the economic value they invest on tourist trains may be higher than published prices at the time. For instance, they were willing to pay 28.4% and 54.9% more for the O-train and V-train types, respectively, according to the study, suggesting that the quality as perceived by train passengers for tourist train services is relatively high. The study is significant in that it succeeded in quantifying the satisfaction level of tourist train passengers using quantitative data (additional funds people are willing to pay).

• Journal of the Korea Institute of Building Construction
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• v.19 no.6
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• pp.557-566
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• 2019

The construction industry has the most safety accidents of any of the domestic industries. Special care must be taken because disasters in the construction industry lead to social problems caused by huge property losses and casualties. As a result, there is a growing awareness of disasters occurring in the construction industry, and government departments are tightening their regulations on safety management. In particular, the OSHA (Occupational Safety and Health Agency) focuses on the expansion of protection targets and the clarification of responsibility in the full amendment OSHA. As a result, a study that focuses on the client's responsibility for safety management is needed. In this study, the project performance capability assessment of construction project management contractors, which is being carried out with uniform assessment criteria without considering the characteristics of the construction project, is considered and all the amendments to the OSHA are considered, and the factors were derived for improvement measures.

• Journal of the Korean Society for information Management
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• v.36 no.1
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• pp.7-30
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• 2019

Open Science Project, which enables users to access and utilize public research results in a digital format, is being actively promoted overseas, and American university libraries are interested in research support service. Among the three OECD implementation measures, 'capacity building' can be effectively prepared through librarians' research support services. Therefore, this study investigated the policy of research support service implemented in leading American 13 university libraries in preparation for the open science era focusing on the recent literatures and library websites. Based on the best cases of research support service of American university libraries, I analyzed the homepage of 19 domestic research universities' library focusing on scholarly communication service and suggested improvements. In Korea, open access service and management of research data are lacking in terms of experience and expertise. This study result can be used as a basic reference when establishing the research support service plan needed in the open science era in the university library and can contribute to the improvement of the research ability of domestic researchers by introducing internationally competitive research support services.