• 한국자동차공학회논문집
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• 제21권6호
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• pp.92-99
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• 2013

High oil price and global warming problem are being continued all over the world. For this reason, fuel economy and emission of greenhouse gas are regulated by law in many countries. Therefore many companies are researching and producing hybrid electric vehicles (HEVs) which substitute conventional internal combustion engine vehicle. However, these researches and productions are restricted to mainly passenger cars. Because of cost and physical problems, commercial vehicles are difficult to evaluate fuel economy. So simulations are important and it is necessary to know how sensitive parameters that enter into simulation affect. In this paper, forward simulations using AVL Cruise were conducted for analysis of fuel economy for parallel hybrid bus and were repeated by changing each parameter. Based on these results, root mean square errors (RMSE) are calculated for analysis of fuel economy sensitivity. The number of target parameters are 15. These parameters were classified with high and low sensitivity parameter relatively.

• 한국수소및신에너지학회논문집
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• 제25권2호
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• pp.161-172
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• 2014

Hydrogen, which can be produced from abundant and widely distributed renewable energy resources, seems to be a promising candidate for solving the concerns for improving energy security, urban air pollution, and reducing greenhouse gas emissions. The two primary motivating factors for hydrogen economy are fossil fuel supply limitations and concerns about global warming. But the safety issues associated with hydrogen economy need to be investigated and fully understood before being considered as a future energy source. Limited operating experience with hydrogen energy systems in consumer environments is recognised as a significant barrier to the implementation of hydrogen economy. To prevent unnecessary restrictions on emerging codes, standards and local regulations, safety policies based on real hazards should be developed. This article studies briefly the direct impact-distances from hazard events such as hydrogen release and jet fire, and damage levels from hydrogen gas explosion in a confined space. Based on the direct impact-distances indicated in the accident scenarios and consumer environments in Korea, the safety policies, which are related to hydrogen filling station, hydrogen fuel cell car, portable fuel cell, domestic fuel cells, and hydrogen town, are suggested to implement hydrogen economy. To apply the safety policies and overcome the disadvantages of prescriptive risk management, which is setting guidance in great detail to management well known risk but is not covering unidentified risk, hybrid risk management model is also proposed.

• 한국자동차공학회논문집
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• 제25권2호
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• pp.207-218
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• 2017

Improving fuel consumption, particularly that of commercial vehicles, has become a global concern. The reduction in logistics cost has been a key issue in efforts to improve fuel economy and efficiency of transportation equipment. Typical technologies for reducing reduce fuel usage include air resistance reduction technologies, tire rolling resistance technologies, and idle technologies among others. Air resistance technology is a highly effective method that can be easily applied in a short period. As with air resistance technology, several devices involving side skirt, boat tail and gap fairing have been developed based on an analytical 3-D modeling technique for reducing air resistance attributed to the vehicle configuration. The devices were on a 45 feet tractor-trailer and the emission test was done using PEMS equipment. Fuel economy was evaluated by introducing several devices to reduce outer air resistance. The test was conducted by changing the experimental method of SAE J1321 Joint TMC/SAE Fuel Consumption Test Procedure - Type II test. As a result, air resistance decreased by at least 15 % and fuel economy improved by at least 13 %. This study sought to reduce greenhouse gas and improve fuel economy by applying several devices to a test vehicle to lower air resistance.

• 동남아시아연구
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• 제27권1호
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• pp.163-191
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• 2017

이 글은 2016년을 정점으로 한 최근 베트남의 정치, 경제, 대외관계를 진단하고 향후 변화를 전망해보는 데 목적을 두고 있다. 정치적으로 베트남은 2016년 공산당대회와 국회의원 선거를 치루며 새로운 국가지도부 구성을 마쳤다. 새로운 지도부에서 눈여겨 볼 점은 공산당의 정치국원과 행정부를 이끌 장관의 비율에서 북부출신이 우위를 지속하게 되었다는 사실이다. 또한 사회주의를 지향하는 시장경제체제를 발전시키기 위하여 공업화와 현대화를 지속적으로 추진하면서 미래를 위한 구조조정에 전력을 다하겠다는 국가발전목표를 제시하였다는 사실이다. 이러한 정치적 결정은 베트남 경제의 원동력이 저가의 노동력을 활용하기 위해 투자하는 외국자본에 토대를 두고 있지만 동시에 대외의존적인 노동집약적 산업에 머물러서는 국가경제의 미래가 불투명하다는 사실에 토대를 두고 있다. 실제로, 베트남이 어려운 대외여건 속에서도 저가생산물 기지로서 입지를 다지고 경제성장을 지속하고 있지만 향후 외자의존도와 사회경제적 불평등을 시정하지 않으면 장기적인 지속성장에 어려움을 겪을 것이 분명하다. 이러한 구조적인 문제에 더하여 단기적으로는 세계경제의 침체, 서구의 금융/화폐 정책, 그리고 무역협정의 불확실성 등이 베트남 경제의 성장을 가늠 하는 변수가 될 것이다. 국제관계에 있어서도 남중국해 등에서 영토분쟁을 겪고 있는 중국과의 관계를 의식하여 미국, 일본, 러시아, 인도 등과 밀접한 관계를 유지하며 외교다변화 정책을 지속할 것으로 보인다. 동시에 보호무역을 천명한 미국의 트럼프 정부가 들어서면서 중국을 포함한 주변 강대국과 정치와 경제를 모두 의식한 균형 있는 외교를 더욱 강화해야 하는 상황에 직면해 있다.

• 항공우주시스템공학회지
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• 제17권4호
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• pp.58-66
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• 2023

최근 글로벌 이슈는 우주경제 및 저궤도 우주통신이다. 3GPP의 2022년 Release 17 표준화에 따라 미국은 2023년 3월, 국가 차원의 저궤도 5G-NTN 우주산업 경쟁력 제고와 생태계 조성 전략을 마련하였다. 글로벌 스마트폰 반도체 제조사들은 표준기반 칩(Chip) 기술의 개발 및 검증 결과를 발표하고, 위성통신 사업자들은 지상통신망 간의 융합으로 저궤도 5G-NTN 우주통신 서비스 및 요금상품을 출시하고 있다. 본 연구는 한국의 저궤도 5G-NTN 우주통신 생태계 현황을 진단한다. 그리고 우리의 생태계 조성 전략을 시장의 공정경쟁, 서비스 법제도, 국가 R&D 거버넌스 체계 측면에서 제시한다.

• 무역학회지
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• 제47권6호
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• pp.55-69
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• 2022

Within the worse of the environment, Climate change caused by global warming is becoming serious around the world, and green logistics to pursue sustainable development in the logistics sector are receiving more and more attention. Along with the acceleration of the global economy, eco-friendly issues are playing an increasingly important role in the logistics industry, and various policy measures are being pursued to establish the green logistics system. This study aims to analyze research trends in eco-friendly logistics, and the SNA methodology was applied by extracting keywords from 518 domestic and foreign papers from 2013 to August 2022. The period is divided into three stages: 2013-2015, 2016-2019, and 2020-2022, and 'logistics' and 'sustainable development' were derived as top logistics eco-friendly keywords at all stages. Besides, In the first stage(2013-2015), the term 'environmental performance' and 'freight transport' attracted the attention of scholars. In the second stage(2016-2019), keywords such as 'third-party logistics' and 'lean logistics' have attracted the attention of scholars. In the third stage(2020-2022), the 'internet of things' and 'circular economy' received the attention of scholars. In line with the growth of the economy, it was confirmed that research related to eco-friendly logistics is gradually expanding to a sustainable concept. Based on this study, it is possible to grasp the research trends of the academic community to cope with recent environmental changes and provides reference materials to consider future research directions.

• 지능정보연구
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• 제28권3호
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• pp.209-235
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• 2022

블록체인 기술은 2010년 이후 인공지능 분야의 발전과 더불어 4차 산업혁명을 선도할 최신의 기술로 각광받고 있고, 기술의 활용 분야에 대한 연구가 활성화되고 있다. 그러나, 자본시장 관점에서 블록체인 경제 생태계를 분류하기 위한 기준과 관련된 연구는 거의 없는 상황이다. 본 연구는 자본시장 관점에서 블록체인 기술을 활용하는 개발자, 사업자, 자본시장 참여자 등 전문가를 대상으로 인터뷰와 사례 연구 방법론으로 블록체인 기술의 응용 분야에 따른 블록체인 경제 생태계를 분류하였다. 자본시장의 주식 투자와 연계해 활용할 수 있는 방안으로 블록체인 경제 생태계 분류 방법을 활용하여 투자 종목 유니버스를 구성하였다. 나아가 본 연구는 퀀트 및 인공지능 전략 기반 정성적, 정량적 분석으로 지능형 주식 포트폴리오를 구축하고 성과를 분석하였다. 이를 통해 블록체인 경제 생태계의 지속적인 성장 전망에 따른 성공적인 투자전략을 제시하였다. 본 연구는 블록체인의 표준화를 기술적 관점이 아닌 자본시장의 관점에서 블록체인 경제 생태계로 분류하고 분석했을 뿐 아니라, 실제 글로벌 우량 상장 주식을 대상으로 포트폴리오를 구축하고 양호한 성과를 달성할 수 있는 전략을 도출한 연구로서 시사점을 갖는다. 또한, 본 연구가 제안하는 블록체인 경제 생태계 기반 지능형 주식 투자 포트폴리오 구축 접근은 블록체인의 기술적인 가치에 초점을 맞춘 연구에 비해서, 투자론과 경제학적인 관점에서 통찰력을 제시해 자본시장 발전에 기여할 수 있다는 실무적 시사점을 갖는다.

• 무역상무연구
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• 제52권
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• pp.47-71
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• 2011

This thesis examines the problems faced in the electronic trade platform for which improvements are necessary, and suggests various ways of overcoming those problems. Practical implications regarding the advancement of Korea's u-TradeHub system are as follows. First, from the technical and legal aspects, to make up for a lack of support systems for spread of users, it is required to promote customized advertising strategies through Ministry of Knowledge Economy and establish a global certification system. Second, document standardization and digitalization should be achieved in advance to make the documents distributed through the e-Trade platform in a seamless manner. Furthermore, an ongoing global network development project should be promoted through the e-Trade platform to achieve standardization. Third, from the operational aspect, it is important to maintain an integrated and systematic relationship with related organizations. Because vertical integration among logistics service providers and GSCM are enabled through the e-Trade platform, it is necessary to standardize global network-based linkage and operating systems.

• 동력기계공학회지
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• 제21권6호
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• pp.110-116
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• 2017

Recently the global warming caused by greenhouse gas has emerged as a global environmental problem. For this reason the continued efforts to reduce greenhouse gas emission by international cooperation and each country are in progress. Climate changing has been recognized as the world economy development from fossil fuel use is the culprit. The international maritime organization marine environment protection committee of the global warming reduction emerged restrictions on air pollution have been strengthened. Therefore, the author has investigated the effects of fuel temperature on the characteristics of combustion and performance, using an four-cycle, six cylinders and direct injection diesel engine. The results of cylinder pressure, rate of pressure rise, rate of heat release and specific fuel consumption were increased by changing of fuel temperature.

• 통상정보연구
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• 제8권4호
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• pp.343-368
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• 2006

The rapid expansion of regionalism has resulted in the creation of blocs of the global economy, so that those countries not belonging to one or more blocs can be discriminated. The purpose of this paper is to examine the competition policy theoretically, international background with issues, and discussion trend of global enterprise. By doing them, this paper suggests the responsive plan, future prospects, and policy directions for the competition policy by distribution service. There is not a statistically significant relationship between international diversification strategy and firm performance. However, we observed some tendency that the larger the firm size, the higher the firm performance, assuming the degree of international diversification or multinationality to be constant. However, the export productivity increase after 1~2 years, and there exits a clear evidence that the innovation investment increases a firm's export competitiveness as time goes on.