• Magazine of the Korea Concrete Institute
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• v.11 no.4
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• pp.61-67
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• 1999

물론 이 글이 콘크리트 분야에 종사하는 사람이 알아야 하는 모든 것을 언급하지는 않는다 ; 본인의 저서 'Properties of Concrest'의 판매에 나쁜 영향을 주고 싶지도 않다. 내가 원하는 것은 콘크리트를 제작할 때 우리 모두가 주의를 기울여야 하는 중요한 몇 가지를 강조하는 것이다. 포트랜드 시멘트만 들어있는 보통의 콘크리트가 사용되는 시대는 이미 사라져가고 있고, 단순한 응용을 제외하고는 곧 사라질 것이다. 대부분의 경우는 가능한 일련의 시멘트계 재료 중에 선택을 해야 한다. 혼화제, 특히 고성능 감수제는 중요한 역할을 한다. 물을 많이 첨가하는 것이 작업성을 높이는 유일한 방법도 아니고 최선의 방법도 아니다. 성능을 기준으로 한 기준설정에 관여하는 사람은 이 모든 것을 명심해야 한다. 그렇지 않으면 시방기준에 명시된 규정과 근원적인 요구사항이 잘못 이해되고, 시험배합을 통해서만 잘못되었다는 것이 분명해지게 된다. 그 단계에서는 예상보다, 비록 틀린 것이지만, 더 많은 비용이 들 것이다. 시방규정은 통상적인 조항 외에 갈수록 내구성에 관심을 더 많이 보인다. 가끔은 내구성이 구조물의 기대수명에 대한 연수로 표현되기도 한다. 이 숫자를 배합재료에 관한 자료로 변환시키는 데는 여러 배합재료 및 배합비가 콘크리트의 성질에 미치는 영향에 관하여 깊이 알고 있어야 한다. 모든 사람이 그러한 구체적인 지식을 가질 필요는 없지만, 각 조직마다 상의할 수 있는 사람은 있어야 한다. 엔지니어가 언급한 규정이 따로 없고, 도면의 주를 참고하거나 구체적인 절이 명시되지 않은 상태에서 국가 시방기준을 통해서 조금씩 내용을 수집해야 하는 경우의 상황은 더 난감하다. 이러한 경우는 배합설계나 재료의 선택을 책임지고 있는 사람이, 환경에 대한 노출조건 및 필요한 배합재료에 관하여 잘 알고 있어야 한다. 일반적으로 말해서 콘크리트의 배합은 필요한 특정용도에 따라서 선택되어야 한다. 이것이 사람들이 고성능 콘크리트라 부르는 것이라고도 할 수 있다. 내 생각으로는 고성능 콘크리트와 보통 콘크리트의 경계는 곧 사라질 것이고, 앞으로 대다수 고객에게 주문 콘크리트 혹은 맞춤 콘크리트를 제공해야 할 것이다. 만약 이러한 접근방식에 더 많은 비용이 든다면, 그것을 보상하는 방법은 콘크리트에 대한 이미지를 높이고, 또한 앞으로 모든 용도에 계속적으로 이용될 수 있도록 하는 것이다. 아니면 구조물을 보수하고, 보수한 것을 또 보수하고, 해체하고 해야 할 것이다. 결국은 재활용 골재를 생산할 수 있다고 웃으면서 말할지 모르지만, 이런 식으로는 불만을 지닌 사용자가 콘크리트를 가능하면 멀리하게 만들 것이다. 콘크리트는 절대 심각한 경쟁에 처하지 않을 것이라는 가정은 무모하다. 내가 배합비에 대해서 강조해 왔지만, 이것으로 최종적으로 좋은 콘크리트가 된다는 보장은 없다. 비빔에서는 일반적으로 큰 문제는 없지만 골재에 함유된 수분을 더 잘 제어해야하고 주의를 게을리하지 말아야 한다. 비빔시간은 모든 재료가 잘 섞이기에 충분해야 하는데, 마이크로 실리카가 포함되어 있을 경우에는 더욱 그렇다. 단위시간당 믹서의 작업량을 높이기 위해서 충분히 비비지 않아서는 안된다. 그리고 마지막으로, 콘크리트가 타설되고 다져진 후, 적절하게 양생이 되어야 한다. 마이크로 실리카가 배합에 사용되었을 경우에는 특히 그러하지만, 이것은 모든 콘크리트에서 양생을 잘하는 것이 피복부에서 유해물질이 유입되는 것을 최소화하고 철근을 완전히 보호하는데 있어서 절대적이다. 내가 지금까지 말한 것은 콘크리트에 관한 충분한 지식과 이해를 필요로 한다. 이것은 당연하고 또한 적절한 것이라고 생각한다. 왜냐하면 더 이상 콘크리트를 수준낮은 싸구려 재료로 간주해서는 안되기 때문이다.

• The Korean Journal of Air & Space Law and Policy
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• v.28 no.2
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• pp.145-181
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• 2013

General aviation is an integral part of civil aviation and involves the widest range of aviation segments except commercial aviation. Featured with different operational procedures and practices to satisfy the economic needs and safety requirements of a sovereign state, general aviation tends to be regulated by an individual state. The last three decades have seen exponential growth of commercial air transport in China, but its general aviation sector has remained disproportionally underdeveloped. With the deepening of the reform of low-altitude airspace, the sector is poised for a radical change and rapid growth. However, legislation governing general aviation activities in China is distorted causing inconsistency and confusions in their application and implementation. This paper aims to analyse China's prevailing legislation regulating general aviation activities. It first discusses the various definitions adopted by ICAO and its member states and reviews the development of general aviation in the US, EU, Australia and China. It then examines the sources of China's general aviation laws, e.g. Chicago Convention and its annexes, and Chinese domestic legislature which covers legislation, laws, directives, rules and procedures. The paper continues to analyse and establish the deficiencies of its prevailing legal framework by pointing out the following: variation of definitions in different regulations, inconsistency of principles in existing laws and regulations, legal vacuum concerning government subsidy, environment protection, safety and security, and other operational areas such as aerial club, sightseeing, and search and rescue. In this process, the paper argues that a coherent, consistent and systematic legal framework is required in order to ensure fair competition and safety for a healthy, progressive and sustainable general aviation growth. Suggestions for rectification and improvement are proposed.

• Journal of the Korea Institute of Building Construction
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• v.15 no.2
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• pp.237-247
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• 2015

The project management information system (PMIS) has recently been developed by using the information technology(IT) in order to implement advanced information management technology to construction industry in Korea. The PMIS has been applied not only to domestic construction projects, but also to some overseas projects executed by Korean construction companies. This study was performed to develop the PMIS that is tailored to the US construction IT market. It has been monopolized by the US-based IT companies, but other companies are recently emerging with competitive technology and market strategy. As a preceding study, existing commercially available systems were analyzed, and the required features of the PMIS were identified by analyzing the core elements of contract, process and cost management about construction projects in the US. Then, the PMIS was developed based on the aforementioned analysis results. The system includes the document management module with an internal electronic approval system, the cost-plus-based automatic labor cost calculation module, and the progress management module to support the integrated project cost management. In addition, the functionality of the developed system was verified by experts about construction management in the US via questionnaire survey. The developed PMIS, in this study, is expected to be applied not only to the US construction IT market as a system specialized for the US construction industry, but also to other oversea markets in the future.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.249-256
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• 2007

AIn this paper, a new desist of LDI controller IC for general purpose is proposed for driving the LDI(LCD Driver Interface) controller in $4{\sim}9$ inches sized portable small-medium TFT-LCD(Thin Film Transistor addressed -Liquid Crystal Display) panel module. The designed LDI controller was verified on the FPGA(Reld Programmable Gate Array) test board, and was made the interactive operation with the commercial TFT-LCD panel successfully. The purpose of design is that it is standardized the LDI controller's operation by one LDI controller for driving all TFT-LCD panel without classifying the panel vendor, and size. The main advantage for new general-purpose LDI controller is the usage for the desist of all panel's SoG(System on a Glass) module because of the design for the standard operation. And in the previous method, it used each LDI controller for every LCD vendor, and panel size, but because a new one can drive all portable small-medium sized panel, it results in reduction of LDI controller supply price, and manufacturing cost of AV(Audio Video) board and panel. In the near future, the development of SoG IC(Integrated Circuit) for manufacturing more excellent functional TFT-LCD panel module is necessary. As a result of this research, the TFT-LCD panel can make more small size, and light weight, and it results in an upturn of domestic company's share in the world market. With the suggested theory in this paper, it expects to be made use of a basic data for developing and manufacturing for the SoG chip of TFT-LCD panel module.

• Journal of Korea Port Economic Association
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• v.35 no.3
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• pp.61-72
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• 2019

In order to enhance the competitiveness of the container shipping industry and promote its development, based on the empirical analyses using multivariate time series models, this study aims to suggest a few strategies related to the dynamics of the container shipping market. It uses the vector autoregressive (VAR) and vector error correction (VEC) models as analytical methodologies. Additionally, it uses the annual trade volumes, fleets, and freight rates as the dataset. According to the empirical results, we can infer that the most exogenous variable, the trade volume, exerted the highest influence on the total dynamics of the container shipping market. Based on these empirical results, this study suggests some implications for ship investment, freight rate forecasting, and the strategies of shipping firms. Concerning ship investment, since the exogenous trade volume variable contributes most to the uncertainty of freight rates, corporate finance can be considered more appropriate for container ship investment than project finance. Concerning the freight rate forecasting, the VAR and VEC models use the past information and the cointegrating regression model assumes future information, and hence the former models are found better than the latter model. Finally, concerning the strategies of shipping firms, this study recommends the use of cycle-linked repayment scheme and services contract.

• Proceedings of the CALSEC Conference
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• 1999.07a
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• pp.41-50
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• 1999

최근의 CALS 시스템 구축 가속화 및 전자상거래 활성화 분위기는 정보기술의 전략적 활용의 초점을 개별기업 위주에서 기업간 협력체제 구축과 이를 바탕으로 하는 기업간 전자적 결합(Electronic Integration)으로 옮기고 있다. 우리는 정보기술의 공유를 기반으로 새로운 기업간의 관계를 구축할 수 있으며, 이러한 관계를 전략적으로 활용함으로써 기존 사업에서의 경쟁우위 뿐만 아니라, 새로운 사업기회를 창출할 수 있다. 관련기업간의 데이터 표준화를 통한 정보의 공유는 CALS 시스템 구축의 바탕이 된다고 할 수 있는데, 정보공유의 범위는 산업별 특성과 제품별 특성에 따라 달라질 수밖에 없으며, 관련기업간의 교섭력(Bargaining Power)에 의해서도 영향을 받게된다. CALS 환경에서는 개별기업의 정보전략에 따라 수직적 협력관계에 있는 기업들간의 정보공유 정도와 수평적 협력관계에 있는 기업들간의 정보공유 정도가 결정된다고 할 수 있다. 정보공유의 범위를 설정하는 데에는 기업간에 이루어지는 업무의 성격, 공급-제조-유통으로 연결되는 관련기업간의 구조 등도 크게 영향을 미치는 것으로 파악되고 있다. 이 연구에서는 CALS 시스템 구축과정에서 우리가 고려할 수 있는 정보공유의 범위를 관련업무공유, 시스템공유, 부품 설비공유, 시설공유 등의 관점에서 분석하여 봄으로써, 각 산업별로 진행되고 있는 시범사업들의 시스템 영역의 범위를 재조명해보고자 한다. 이 연구에서 집중적으로 다루게 될 정보공유의 범위에 대한 내용은 CALS 시스템을 개발하려는 기업들의 응용서비스 개발 및 정보전략 구축에 중요한 공헌을 할 수 있을 것으로 기대된다.진" 사업에 대한 표준 설정을 위하여 노스캐롤라이나주 지방보건소의 "보건교육/건강증진" 표준체제를 예로 들었다. 다음으로, 경제적인 효율면에서 볼 때 "보건교육/건강증진" 사업에는 단기 혹은 장기 투자가치가 있는가 하는 것이다. 새로 태어나는 미국 지방 보건소의 "보건교육/건강증진" 활동은 지역 시민 및 그 단체가 광범위하고도 자연 다발적으로 참여할 때만 성공할 수 있다고 결론 지울 수 있다.한 분야별 전문가시스템 개발을 지양하고 MCRDR이론을 기반으로 한 범용성 있는 전문가시스템 개발 툴의 개발에 관한 연구를 소개한다. 후 새로운 지식을 얻는 반복적인 Explanation-based Data Mining Architecture를 제시하였다. 본 연구의 의의로는 데이타 마이닝을 통한 귀납적 지식생성에 있어 귀납적 오류의 발생을 고메인 지식을 통해 설명가능 함을 보임으로 검증하고 아울러 이러한 설명을 통해 연역적으로 새로운 가설지식을 생성시켜 이를 가설검증방식으로 검증함으로써 귀납적 접근과 연역적 접근의 통합 데이타 마이닝 접근을 제시하였다는데 있다.gical learning to give information necessary to improve the making. program and policy decision making, The objectives of the study are to develop the methodology of modeling the socioeconomic evaluation, and build up the practical socioeconomic evaluation model of the HAN projec

• Journal of the Korean Chemical Society
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• v.40 no.6
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• pp.445-452
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• 1996

Catalytic hydrogenation of ketones and aldehydes by RuH(NO)$L_3$ ($L_3$: $PPh_3$, PhP($CH_2CH_2PPh_2$)$_2$(etp)) was investigated to examine the reaction mechanism and the competence of hydridonitrosyl complexes as catalysts for organic synthesis. RuH(NO)$L_3$ showed catalytic activity for the hydrogenation and the activities of catalysts were dependent on the steric and electronic factors. The less the steric demands of the substrates become, the more activity the catalysts show. For the electronic effect, the more the partial positive charge on the carbonyl carbon atom in ketones becomes and the more the double bond character of carbonyl group in aldehydes becomes, the more active the catalysts are. These results reflect the difference of reaction mechanisms of two substrates, ketones and aldehydes. Catalytic activities of RuH(NO)(etp) and RuH(NO)($PPh_3$)$_3$ in the presence of extra $PPh_3$ toward hydrogenation showed the existence of a reaction pathway accompanied with the change of the bonding modes of NO ligand. The roles of excess $PPh_3$ change with increase of the mole ratio of $PPh_3$ to catalysts; prevention of ligand dissociation from comlexes → bases → ligands. The activity of RuH(NO)(etp) was lower than that of RuH(NO)($PPh_3$)$_3$ toward the hydrogenation of the same substrates mainly due to the structural difference. These catalysts showed the selectivity toward olefin hydrogenation over carbonyl groups in the competitive reaction.

• Journal of Korea Port Economic Association
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• v.25 no.1
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• pp.107-124
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• 2009

In order to create value for maritime tourism industry, new port infrastructures have been planned, improvements in passenger terminal services have been designed, and new maritime transport technologies have been applied, so that ports improve their efficiency and the quality of their service more than their national and international competitors. Thus, the purpose of this study is to verify the dimensions of the service quality of ocean passenger terminal. Based on a survey of 260 customers in port of Busan and Inchon, terminal service quality's five main dimensions have been checked regarding their fit with the use of Confirmatory Factor Analysis. Empirical results support that this is a valid instrument for measuring service quality of a ocean passenger terminal. The interactive sequence of computing Cronbach's alpha, corrected item-to-total correlation, and factor analysis was repeated a few times and resulted in a final set of 19 items representing five distinct dimensions-tangibles, responsiveness, knowledge, reliability, and accessibility. This finding provides the more appropriate instrument to evaluate the customers perception as well as to measure the service quality of ocean passenger terminal.

• Journal of Service Research and Studies
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• v.10 no.3
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• pp.1-22
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• 2020

This study was conducted to derive the new manager model in service economy era. It was logically explained that the modern economic society is different from the existing economic society, the modern organization that is the subject of management is different from the existing organization, and the tasks required by management are different from the existing tasks. It suggested the managerial model required for new managers. According to the proposed manager's model, the tasks required of new managers and essential qualities as managers to perform the tasks were presented. It suggested the role model that managers with required qualities should play. The role of a manager who becomes one with customers, the role of a manager who controls even his irrationality, the role of a manager who combines discernment and indiscriminateness, a flexible leadership role that combines charisma and tenderness, an administrator role that embraces regulations and non-regulations, and vision and non-vision. We derived the role of a manager who manages management, and a manager role model that utilizes both competition and non-competition. The managers engage in two opposing roles and perform management activities in a spiral dialectical cycle that develops while resolving the contradictions of each role. The method of embracing the two opposing parties internally and externally and the dialectical management execution process according to the change of the space-time axis were presented by borrowing the models of The Book of Change. Future research needs an empirical analytical study on this new Model. There is a need for studies that expand this study and develop it into a practical model and verify it in an analytical way.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.3
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• pp.285-288
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• 2020

The demand for coating technology on electric power equipment that has arisen from such issues regarding the attaching of illegal advertisements and posters to electric power distribution boxes such as TR, SW, etc. in down town areas seeks to produce functional coating surfaces using polymers and nano-materials that will result in improvements in self-cleaning performance and greater stability even under harsh environmental conditions. KEPCO-coatings consist of copolymerized acrylic resin and methacryl-modified reactive silicone that are able to chemically combine, which results in performance improvement without any leakage of of silicone, thus contributing to its properties of high-stability. Thus, the research team has also started long-term on-site testing on 9 electric power distribution spots around a city center in cooperation with the KEPCO Daeduck-yusung branch. The KEPCO-coating technology could advance the best coating materials and processes to meet appropriate circumstances for a variety of outdoor damage environment. It is also predicted that KEPCO could be possible to expand international electric maintenance markets and to arrange business platforms if KEPCO would achieve its original technology (IPs) by the means of upgrading in self-cleaning coating technology and obtaining long-term on-site test records from nationwide electric facilities.