• 한국항해학회지
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• 제20권3호
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• pp.1-11
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• 1996

The accuracy for determining fishing ground and for setting fishing gear location, and the repeatability of ship position vary depending on fishing methods. Especially, Loran-C has been served to give fisherman highly accurate ship's position, and a number of fishing vessel are equipped with it's receivers. In this paper, in order to evaluate the accuracy of Loran-C fix of Korean chain in Korean southeast coast, the authors examined and analyzed the data of the receiver of Loran-C(LC 90, Furuno) and GPS(AccNav $Sport^{TM}$, Eagle) measured automatically and continuously for 2 seconds at interval of 5minutes during 2hours from $11^{th}$ to $21^{st}$, July, 1996 at six observed points, that is, Pusan, Wolnae, Pangojin, Chongja, Kampo and Kuryongpo in Korean southeast coast. As the result obtained, Loran-C signals showed little fluctuation with good reprodutibility. Good stability of Loran-C signals was indicated by the small value of the standard deviation 0.064~0.094$\mu\textrm{s}$. Although determination of the observed position could not be completely accurate, the extent of the error was estimated smaller than 0.35 nautical mile.

• Journal of Information Technology Applications and Management
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• 제23권4호
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• pp.1-23
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• 2016

The growth of information and communication technology (ICT) has led to a rapid of business paradigm shift incurred in the creation of new social/market value, changes of a value chain and elements producing a value creation, and enlargement of the scope of market competition. It leads to the change and evolution of industrial structure, requiring innovations of policy and institution. However, most studies that have focused on the effect of policy and institution on innovation are based on thick description and qualitative evidence, while paying little attention to these linkages in an empirical way. Hence this study has attempted to empirically analyze policy and institutional factors affecting innovation performance, particularly attention to ICT industry in OECD countries. The findings derived from the empirical analysis provide important implications for catch-up countries in relation to the innovations of policy and institution for effective innovation system and start-up ecosystem.

• Architectural research
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• 제15권3호
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• pp.167-174
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• 2013

Due to increasing competition of construction companies, it is required to optimize the management of construction projects and "lean" concepts are rapidly spreaded in construction industry. Steel work accounts for a large proportion in construction work, and a variety of attempts to efficiently perform steel work has currently made. And since rebar (Engineer-to-Order) can be engineered through design once order is placed, it gives the great impact on construction, thus, entire management is required. The purpose of this study is to present the method to increase the efficiency of field processing method of steel work in terms of lean construction. Once we examine process of steel work and identify the flow, we would like to analyze which processes should be improved through value analysis approach and present the improvement plans. Also, this study examines cases of field processing and factory processing, and it identifies the waste factors in the procurement process. Finally, this study would like to present the result of analysis from the perspectives of value. The rebar delivery process is divided into several steps and the duration of every step is surveyed. Using duration data, VAT (Value added time) can be calculated for analyzing the efficiency of the process.

• 무역학회지
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• 제46권3호
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• pp.45-63
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• 2021

This paper investigates the effects of China's participation in global value chains (GVC) on the productivities focusing on the manufacturing industries. In this study, several indicators of participation in global value chains were used. These include GVC participation, forward GVC participation, backward GVC participation and GVC position index. In particular, we used the data obtained from 18 manufacturing industries in China during 15 years from 2000 to 2014. The main results of the analysis are as follows. First, the higher the degree of total participation in GVC, the higher the productivity. This means that with the increase in exports and imports of intermediate goods, productivity has increased through technology spillover effects or competition effects, and so on. Second, the backward participation does not increase the productivities significantly while forward participation leads higher productivity. Third, the productivity improvement effects of GVC participation was larger in the high-tech industries than in the low-tech industries. These results show that GVC participation was helpful for the economic growth of China and the efforts for moving toward upstream production stage in GVC is necessary for the improvement of international competitiveness in Chinese manufacturing industry.

• 디지털산업정보학회논문지
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• 제15권1호
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• pp.1-7
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• 2019

The objective of this study is to examine the trends in big data. Research abstracts were extracted from 4,019 articles, published between 1995 and 2018, on Web of Science and were analyzed using topic modeling and time series analysis. The 20 single-term topics that appeared most frequently were as follows: model, technology, algorithm, problem, performance, network, framework, analytics, management, process, value, user, knowledge, dataset, resource, service, cloud, storage, business, and health. The 20 multi-term topics were as follows: sense technology architecture (T10), decision system (T18), classification algorithm (T03), data analytics (T17), system performance (T09), data science (T06), distribution method (T20), service dataset (T19), network communication (T05), customer & business (T16), cloud computing (T02), health care (T14), smart city (T11), patient & disease (T04), privacy & security (T08), research design (T01), social media (T12), student & education (T13), energy consumption (T07), supply chain management (T15). The time series data indicated that the 40 single-term topics and multi-term topics were hot topics. This study provides suggestions for future research.

• 한국콘텐츠학회논문지
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• 제21권1호
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• pp.12-23
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• 2021

수출 비중이 높은 한국은 다른 국가들에 비해 글로벌 가치사슬(GVC)에 대한 의존도가 높기 때문에 GVC변화에 민감한 구조를 지니고 있다. 이는 과거부터 한국의 수출이 특정국가와 품목에 편중되어 있으며, 수출제품을 만들기 위해 필요한 소재·부품·장비들을 대부분 수입에 의존하는 경향이 있기 때문이다. 현재 우리나라는 일본과의 무역분쟁을 겪고 있으며 소재·부품·장비의 수입 의존도가 높은 일본과의 무역분쟁은 GVC 공급 불균형을 야기해 우리나라 산업 전반에 영향을 미칠 수 있다. 따라서, 일본의 수출규제로 인한 경제피해를 최소화하기 위해서는 대일의존 수입품들의 수입다변화 및 국산화를 통한 대일의존도를 낮추는 형태로의 GVC 체질 개선이 필요하다. 이러한 체질 개선을 이루기 위해서는 우선적으로 대일의존 수입품들을 도출하고 수입다변화와 국산화가 필요한 수입품들을 선별하여 수입다변화와 국산화를 진행해야 할 것이다. 또한 대일의존 제품의 국산화 목표달성을 위한 R&D 투자전략 수립이 반드시 필요할 것이다. 이러한 R&D 투자전략 수립은 기존에는 전문가 중심의 정성적 방식이 많이 이용되어 왔지만, 본 논문은 이와는 차별화된 데이터 기반의 정량적 분석결과를 토대로 한 R&D 투자전략에 대해 논의하고자 한다.

• Tuberculosis and Respiratory Diseases
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• 제72권2호
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• pp.156-162
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• 2012

Background: The main goal of this study was to evaluate the diagnostic efficacy of reverse transcription-nested polymerase chain reaction (RT-nested PCR) in bronchial washing fluid with MAGE A1-6 common primers for the detection of lung cancers invisible by bronchoscopy. Methods: To determine the expression of MAGE A1-6 gene in 189 lung cancers diagnosed by conventional fluoroscopy-guided lung biopsy and 89 cancer-free controls, RT-nested PCR was performed in bronchial washing specimens. We analyzed MAGE A1-6 RT-nested PCR data according to tumor histology, stage, size, and compared them with cytological data. Results: 189 patients (111 cases in adenocarcinoma, 47 cases in squamous cell carcinoma, 22 cases in small cell lung carcinoma, and 9 cases in other cancers) and 89 benign patients were investigated. The expression of MAGE was performed by nested RT-PCR using common MAGE primer. Among 189 cancer patients, the expression rate of MAGE was 49.2%, and the positive predictive value was 89.4%. However, the expression rate of MAGE in patients with benign lesions was 12.4%. In peripheral lung cancer, the positive rate of MAGE expression was 57.4% in squamous cell carcinoma, 44.1% in adenocarcinoma and 59.1% in small cell lung cancer. Whereas the expression rate of bronchial washing cytology in peripheral lung cancer was 9.0% (p=0.011). Conclusion: MAGE RT-PCR in bronchial washing fluid gave us promising data for the detection of peripheral lung cancer. It could be a useful method for selecting diagnostic tools for peripheral lesions.

• 산업공학
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• 제24권2호
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• pp.139-150
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• 2011

The EPCglobal Network is a computer network used to share product data among trading partners. It provides the supply chain with improved visibility and traceability by using Electronic Product Code (EPC), which is stored on an RFID tag. Although this network model is widely accepted as a global standard and the growth of EPCglobal-subscriber base is considerable, the EPC technology adoption process is still in its infancy. This is because some of the critical issues on this model still remain to be verified such as scalability, data management, security, privacy and the economic value of data sharing. In this paper, we focus on scalability issue among the challenges to overcome and we regard performance of the EPCglobal Network only as a track and trace query-processing cost in the network. We developed performance models consisting of three elements of the EPCglobal Network : Discovery Services (DS), EPC Information Services (EPCIS), Object Naming Services (ONS). Then we abstracted out the track and trace query execution model to evaluate performance of the overall EPCglobal Network. Finally using the proposed models, we carried out simulation analysis based on an RFID-based inbound logistics process of automobile parts. This work is an important step towards the EPC technology diffusion and provides guidelines for businesses looking to buy or build the EPCglobal Network-based systems.

• 한국IT서비스학회지
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• 제19권2호
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• pp.109-124
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• 2020

Facing the 4^th Industrial Revolution era, researches on artificial intelligence have become active and attempts have been made to apply machine learning in various fields. In the field of finance, Robo Advisor service, which analyze the market, make investment decisions and allocate assets instead of people, are rapidly expanding. The stock price prediction using the machine learning that has been carried out to date is mainly based on the prediction of the market index such as KOSPI, and utilizes technical data that is fundamental index or price derivative index using financial statement. However, most researches have proceeded without any explicit verification of the prediction rate of the learning data. In this study, we conducted an experiment to determine the degree of market prediction ability of basic indicators, technical indicators, and system risk indicators (AR) used in stock price prediction. First, we set the core parameters for each financial indicator and define the objective function reflecting the return and volatility. Then, an experiment was performed to extract the sample from the distribution of each parameter by the Markov chain Monte Carlo (MCMC) method and to find the optimum value to maximize the objective function. Since Robo Advisor is a commodity that trades financial instruments such as stocks and funds, it can not be utilized only by forecasting the market index. The sample for this experiment is data of 17 years of 1,500 stocks that have been listed in Korea for more than 5 years after listing. As a result of the experiment, it was possible to establish a meaningful trading strategy that exceeds the market return. This study can be utilized as a basis for the development of Robo Advisor products in that it includes a large proportion of listed stocks in Korea, rather than an experiment on a single index, and verifies market predictability of various financial indicators.

• Macromolecular Research
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• 제12권2호
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• pp.172-177
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• 2004

We have studied the lamella-level morphology of poly(ethylene terephthalate) (PET)/polycarbonate (PC) blends using small-angle X-ray scattering (SAXS). Measurements were made as a function of the holding time in the melt. We determined the morphological parameters at the lamellar level by correlation function analysis of the SAXS data. An increased amorphous layer thickness was identified in the blend, indicating that some PC was incorporated into the interlamellar regions of PET during crystallization. The blend also exhibits a larger lamella crystalline thickness (l$\sub$c/) than that of pure PET. A possible reason for the increase in l$\sub$c/ is that the inclusion of the PC molecules in the interlamellar regions causes an increase in the surface free energy of folding. At the early stage of isothermal crystallization, we observed a rapid drop in the value of l$\sub$c/ in the blend; this finding indicates that a relatively large fraction of secondary crystals form during the primary crystallization. In contrast, the value of l$\sub$c/ for the sample that underwent a prolonged holding time increased with time in the secondary crystallization-dominant regime; this observation suggests that the disruption of chain periodicity, which results from transesterification between the two polymers, favors the development of fringed micellar crystals that have larger values of l$\sub$c/ rather than the development of normal chain-folded crystals.