• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.21-26
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• 2006

This paper focuses on modeling and predicting differential GPS corrections transmitted by marine radio-beacon systems using artificial neural networks. Various neural network structures with various training algorithms were examined, including Linear, Radial Biases, and Feedforward. Matlab Neural Network toolbox is used for this purpose. Data sets used in building the model are the transmitted pseudorange corrections and broadcast navigation message. Model design is passed through several stages, namely data collection, preprocessing, model building, and finally model validation. It is found that feedforward neural network with automated regularization is the most suitable for our data. In training the neural network, different approaches are used to take advantage of the pseudorange corrections history while taking into account the required time for prediction and storage limitations. Three data structures are considered in training the neural network, namely all round, compound, and average. Of the various data structures examined, it is found that the average data structure is the most suitable. It is shown that the developed model is capable of predicting the differential correction with an accuracy level comparable to that of beacon-transmitted real-time DGPS correction.

• 한국건축시공학회지
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• 제3권4호
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• pp.103-109
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• 2003

Reinforced concrete structures under sever conditions such as marine structures, bridges and structural constructed with aggregated(dredged front sea). can be deteriorated from corrosion of the reinforcing bars. The purpose of this study is to evaluate the corrosion reflectance of coated steel using polymer dispersion and polymer cement slurry. Polymer dispersion and polymer cement slurry with various polymer types were coated to the surface of bars and steel plate, and tested for accelerated corrosion tests. Tests include adhesion in tension, bending test, chloride ion spray, penetration of NaCl 10％ solution and carbonation. From the test results, the corrosive resistance of steel is considerably improved by using polymer dispersion and polymer cement flurry at surface of steel. The difference of the corrosive resistance is hardly recognized according to types of polymer dispersion. The coated steel using polymer dispersion and polymer foment slurry will be improved to a great extent compared to those of plain steel when increasing content of chloride ion in cement concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.37-38
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• 2022

During the past decades, the corrosion of the steel rebar embedded in concrete structure surrounding marine environment is actually problematic and required the suitable preventive method. An eco-friendly corrosion inhibitor mix is investigated to stifle the active corrosion in comparison with other commercial corrosion inhibitors. The hybrid inhibitor enhances the corrosion resistance and the workability of concrete. However, it reduces the compressive strength slightly after 28-day-age. The electrochemical studies and mechanical studies are pointed out the corrosion resistance property, corrosion kinetics, and the mechanical properties of all concrete samples. H-3 is the optimum dose of hybrid inhbitor that meets the demand of both electrochemical property and mechanical property. It performs the noble features due to the formation of optimum amount of P-Zwitterions-(Cl)-Fe complex onto the steel rebar surface.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.191-192
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• 2023

In recent years, the use of high-strength grout has gained popularity in offshore wind power generation complexes for facility foundations and bridges. These marine wind farms require support for horizontal loads from wind and waves. To ensure the strength of the grout produced in environments similar to the actual placing site, this study investigated the curing of high-strength grout discharged through pump pressure in various environments, and examined the difference in strength according to different variables. Compressive strength measurements revealed that the core specimen collected from the bottom (3cm) and uppermost (50cm) of the specimen exhibited lower strength compared to other height specimens, while the core specimen obtained from the corner exhibited lower strength compared to the center. These findings suggest that the strength difference between the center and the corner is more pronounced when curing at low temperatures. This effect is greater than the strength reduction that typically occurs during low-temperature curing, and thus, necessitates careful attention in similar construction environments.

• 무역학회지
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• 제45권5호
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• pp.23-35
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• 2020

The purpose of this study is to examine relationships among exhibition selection factor, performance, satisfaction and intention to revisit of participants in international exhibition. For this purpose, we set hypotheses relationship among external selection factor of exhibition (ESFE), internal selection factor of exhibition (ISFE), performance of sales (PS), performance of information gathering (PIG), performance of relationship building (PRB), performance of image building (PIB), satisfaction (SAT) and intention to revisit (IR). To verify theses hypotheses, we conducted path analysis on the data from 100 participants of 2019 Korea International Boat Show. The result of this study is as follows: Frist, ESFE positively impacts on PS, PIG, PRB, PIB. Second, ISFE positively impacts on PIG, PRB. Third, PS and PIB positively impacts on SAT. Fourth, SAT positively impacts on IR. The implication of this study is two fold. This study expands research area of international exhibition to a new industry such as marine leisure sports industry and provides useful information to firms that plan to participate in the international exhibition and to those who organize the international exhibitions.

• Ocean and Polar Research
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• 제30권3호
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• pp.351-359
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• 2008

In an effort to develop high-resolution sea surface temperature (SST) proxies for mid-latitude regions, two massive reef-building coral species, Alveopora and Favia, were collected from Jeju and Tsushima Islands, respectively. Their skeletons were subsequently analyzed for annual growth banding, Sr/Ca and Mg/Ca ratios. Hermatypic corals are thinly distributed in the waters of Jeju Island, where Alveopora japonica was the only dominant coral species. A higher diversity of hermatypic corals were observed in the waters of Tsushima Island, where Favia sp. was the most common coral species and even forming an about 6-m-high reef structure. Both Alveopora and Favia showed annual growth layers consisting of couplets of high- and low-density bands. Sr/Ca ratio of both species and Mg/Ca ratio of Alveopora also showed seasonal variation, likely reflecting SST variation. These results suggest the possibility that Alveopora and Favia species can be used as potential SST proxies. However, this study also highlights the potential growth disturbance of middle latitude corals due to high rainfall during monsoon and low SST during winter. This possibility should be taken into account in the investigation of Sr/Ca(Mg/Ca)-SST relationships.

• Journal of Species Research
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• 제5권3호
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• pp.289-299
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• 2016

Extensive survey of invertebrates in Korea, led by the National Institute of Biological Resources in Incheon, continues to uncover many new and endemic species, but also elements of neighbouring faunas that were previously unknown here. Hemicyclops tanakai Itoh and Nishida, 2002 was originally described from estuarine mud-flats in Tokyo Bay, Japan. We report one male and two females from a sandy beach on Jeju Island, which represent its first record in Korea and second record ever. No morphological differences were observed between these two disjunct populations, so we expect more records of this species in Korea and Japan. Tisbe ensifer Fischer, 1860 was originally described from Madeira and later on reported from numerous other parts of the Northern Atlantic, as well as from the Indian Ocean. We report two females from a shallow littoral in Sokcho, which represents its first record in Korea and the first record in the entire Pacific Ocean. Because of morphological discrepancies reported in previous records we recognize that this species might be in reality a species complex, and we only tentatively identify our Korean specimens as T. cf. ensifer. We provide numerous light photographs of both species in addition to short descriptions, in hope that they might elucidate global problems of their zoogeography and dispersal of small marine invertebrates in general. Further samplings from Korea and other parts of the world will be necessary to test our identifications and phylogenetic relationships of Korean populations with molecular and other tools.

• 환경정책연구
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• 제3권2호
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• pp.1-29
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• 2004

As a result of very limited access due to the military confrontation between South and North Koreas for the last five decades, ecosystems in the transboundary coastal area in the western part of Korean Peninsula have been protected from intensive developments in both Koreas. In the core of the recent two military collisions lies the fishery resources represented as blue crabs as well as the politico-military aspect. Increasing development pressures from both sides as reflected in the South Korea supporting the construction of an industrial complex in Kaesung, North Korea, is the main factor which threatens the sustainable resource base in this region. This research is aimed to develop a cooperative management system for the well-preserved transboundary coastal area between South Korea and North Korea. The Pressure-State-Response (PSR) framework of OECD was used to assess environmental conditions, socioeconomic pressures on the environment of the region, and policy responses of both Koreas to those pressures. Protection of ecosystems, peace settlement, and prosperity of the region and the entire peninsula were proposed as the management goals of the cooperative management system. The designation of the area as a Co-managed Marine Protected Area System (COMPAS) through close cooperation among South Korea, North Korea, and international entities was suggested as a way to achieve those goals. Revision of legal and institutional mechanisms, strengthening knowledge base for optimal COMPAS management, integration of the marine protected area and DMZ (demilitarized zone) ecosystem, enhancing stakeholder participation, building international partnership, and securing financial resources were presented as six management strategies.

• 한국전자통신학회논문지
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• 제11권2호
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• pp.125-138
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• 2016

현재 기상정보를 활용하고자 하는 수요는 증가하고 있으나 제공되는 기상기후정보는 한정적이다. 개선을 위해서는 기상기후 빅데이터 활용 플랫폼 지원, 정부 및 공공기관, 기업의 요구에 부응하는 기상기후 빅데이터 전문 인력 양성이 필요하다. 기상기후 빅데이터는 다양한 분야에서 활용 가능한 고부가가치 서비스 제공이 필요하며 서비스의 확대 및 새로운 콘텐츠 개발을 위하여 산업 분야별 유형별 특성에 맞는 맞춤형 서비스가 제공되어야 한다. 맞춤형 서비스를 제공하기 위해서는 국가차원의 협업생태계 조성이 필수적이다. 협업생태계 조성 환경을 만들기 위해서는 해양정책과 기상정책의 융합, 해양학과 기상학의 융합, R&D 기초연구와 응용연구의 융합이 필요하다. 이후 수요분석, 생산정보공유, 단일화 순서로 협업생태계를 구축할 수 있다.

• 대한조선학회논문집
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• 제50권1호
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• pp.14-24
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• 2013

The marine leisure industry in Korea has been the focus of the power of economic growth and the creation of jobs in recent years. In this regard, many studies concerning marine leisure are on-going in various fields. In this paper, developed a layout system and algorithm can resolve the factory and facility layout problem. For a layout design of leisure-boat factories, the leisure-boat production process is analyzed in order to derive standard production space elements for the layout of the factory. Based on the results, a draft design of the factory layout is carried out based on the manpower planning data, as well as the characteristics and relationships of each process data. A layout design of this paper can be verified through a factory simulation solution and we suggest the verification method using a SBD(simulation based design) methodology. The layout system takes into account the user's accessibility and extendibility, so it is web-oriented and uses RIA (rich Internet Application) technology. Furthermore, the system and layout algorithm of this paper are verified with samples data that show the efficient factory arrangement and practical application method.