• 대한교통학회지
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• 제27권3호
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• pp.103-109
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• 2009

항공교통시스템에서 핵심적 역할을 하는 항공사의 운영비 중 유류비용은 가장 큰부분을 차지한다. 따라서 많은 항공사들은 유류비 절감을 위한 많은 노력을 기울이고 있는 실정이다. 이 중 체계적인 항공기 급유계획 전략은 많은 비용절감 효과로 인하여 근래에 많은 주목을 받고 있다. 항공기 급유계획은 항공유의 급유비용이 각 운항공항 별로 상이할 때, 총 유류비를 최소화할 수 있도록 각 항공기의 운항공항에서 최적 급유량을 도출하는 계획이다. 본 연구에서는 항공기 급유계획에 관한 수리모형을 제시한다. 제시된 모형은 각 운항공항의 급유비용과 항공기 경로정보가 알려져 있을 때 각 운항공항에서 총비용을 최소로하는 정확한 급유량을 계산하는 최적화 모형이다. 실험결과, 제안된 모형은 직관적 형태의 발견적 기법보다 효과적인 비용절감이 이루어짐을 확인하였고, 향후 항공사를 비롯한 대형 운송시스템에서 유류관리 전략으로 중요한 역할을 할 것이라 기대된다.

• 국제초고층학회논문집
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• 제3권2호
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• pp.155-165
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• 2014

This study measured and compared the variation of ventilation rate and fan energy consumption according to various control strategies after installing wireless sensor-based pilot ventilation system in order to verify the applicability of demand-controlled ventilation (DCV) strategy that was efficient ventilation control strategy for underground parking lot. The underground parking lot pilot ventilation system controlled the ventilation rate by directly or indirectly tracking the traffic load in real-time after sensing data, using vehicle detection sensors and carbon monoxide (CO) and carbon dioxide ($CO_2$) sensor. The ventilation system has operated for 9 hours per a day. It responded real-time data every 10 minutes, providing ventilation rate in conformance with the input traffic load or contaminant level at that time. A ventilation rate of pilot ventilation system can be controlled at 8 levels. The reason is that a ventilation unit consists of 8 high-speed nozzle jet fans. This study proposed vehicle detection sensor based demand-controlled ventilation (VDS-DCV) strategy that would accurately trace direct traffic load and CO sensor based demand-controlled ventilation (CO-DCV) strategy that would indirectly estimate traffic load through the concentration of contaminants. In order to apply DCV strategy based on real-time traffic load, the minimum required ventilation rate per a single vehicle was applied. It was derived through the design ventilation rate and total parking capacity in the underground parking lot. This is because current ventilation standard established per unit floor area or unit volume of the space made it difficult to apply DCV strategy according to the real-time variation of traffic load. According to the results in this study, two DCV strategies in the underground parking lot are considered to be a good alternative approach that satisfies both energy saving and healthy indoor environment in comparison with the conventional control strategies.

• Transactions on Control, Automation and Systems Engineering
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• 제1권1호
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• pp.75-86
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• 1999

An air-data estimator for generic air-breathing hypersonic vehicles (AHSVs) is developed and demonstrated with an example vehicle configuration. The AHSV air-data estimation strategy emphasized improvement of the angle of attack estimate accuracy to a degree necessitated by the stringent operational requirements of the air-breathing propulsion. the resulting estimation problem involves highly nonlinear diffusion process (propagation); consequently, significant distortion of a posteriori conditional density is suspected. A simulation based statistical analysis tool is developed to characterize the nonlinear diffusion process. The statistical analysis results indicate that the diffusion process preserves the symmetry and unimodality of initial probability density shape state variables, and provide the basis for applicability of an Extended Kalman Filter (EKF). An EKF is designed for the AHSV air-data system and the air data estimation capabilities are demonstrated.

• Asia Marketing Journal
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• 제11권3호
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• pp.167-184
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• 2009

세계 항공시장의 경쟁이 점점 치열해지는 가운데 대한항공은 비용절감을 통해 운영의 효율화를 이루는 한편, 서비스 차별화를 통해 고객 충성도를 강화하고자 노력해 왔다. 최근 고객 충성도를 보다 강화하기 위해 대한항공은 적극적인 문화마케팅 활동을 통해 프리미엄 기업이미지를 제고하고 있다. 대한항공은 세계 3대 박물관과 장기간의 제휴를 맺고, 프랑스 루브르 박물관을 필두로 하여 박물관의 새로운 작품안내 서비스를 후원하고 있다. 뿐만 아니라 이들 박물관에 한국어 안내 서비스가 도입될 수 있도록 후원하여 국가적 위상과 국민의 자긍심을 제고시켰다. 본 사례에서는 단순히 물자와 사람을 수송하는 항공사를 넘어 세계의 도시와 문화·예술을 연결하는 Global Leading Carrier로서 그 역할을 확대해 가고 있는 대한항공의 문화마케팅 도입배경과 구체적인 활동 및 전략을 소개하고, 그 성과 및 특징을 논의하고자 한다.

• 산업경영시스템학회지
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• 제40권4호
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• pp.1-9
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• 2017

Companies must capture value for sustainable growth. Capturing value is a critical task for companies, particularly when operating own businesses and organizations or starting new business. The business strategy of many companies focuses on capturing the maximum value from customers and other stakeholders. Even though a wide range of studies on value creation and appropriation has been conducted in the strategic management field, most of studies are still conceptual and theoretical. Thus more empirical studies are required to suggest future-oriented value strategy. This study reveals the value creation and appropriation elements in the aviation industry of Korea. The purpose of this study is to understand the trend of value creation and appropriation in the industry. In addition, the relationship between the elements and firm's performance are tested. The firm's performance is defined by that past and future point of views. The sample were collected from Korean Air and Asiana Air. The empirical test shows that the elements of value creation-appropriation have significant impact on firm's performance. Further, the element of value appropriation to customer has a positive impact both on firm's past and future performance. Our results show that investors acknowledge a value-based strategy as a sign of stock valuation. The results of this test correspond with the earlier one, showing that maximizing customers value rather than shareholder value does deliver impressive returns. The finding suggest that companies need to change their strategy to efficiently manage performance. With the test results, we propose a value-based strategy to maximize firm's future financial and stock performance.

• Strategy21
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• 통권34호
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• pp.149-177
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• 2014

Today distant oceans around the world are regarded as a major 'global commons' for international trade and transportation. Korea is not an exception, because Korea hugely depends on sea lines of communication (SLOC) for supplying vital commodities such as food and energy resource. As a result, assuring a free and safe use of distant ocean beyond territory is also an important agenda for Korea's maritime security. However there are a number of challenges for Korea to enjoy a free and safe use of distant ocean; dangers of regional maritime conflict in East Asia, naval arms race of China and Japan, and concerns on possible decline of U.S naval presence and power projection capabilities. These factors provide a reasonable basis for Republic of Korea Navy (ROKN) to pursue capabilities for major naval operations at distant ocean in a long-term perspective toward the year 2030. The introduction of aircraft carrier and nuclear-powered submarine is a key requirement for achieving this goal. ROKN needs to acquire a 'multi-role strategic landing platform' type of light aircraft carrier, which takes a role to escort naval task force by providing air superiority at distant ocean. Additionally nuclear-powered submarine will offer ROKN a formidable power to carry out offensive missions effectively at distant ocean.

• Strategy21
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• 통권33호
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• pp.148-177
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• 2014

The regional security and stability in Northeast Asia has become more complicated because of a sudden establishment of China's Air Defense Identification Zone (ADIZ) on 23 November 2013. One dimensional conflicts on the territorial sovereignty over the islands between the regional States has developed into the two dimensional conflicts like maritime delimitations among the States concerned since they have all ratified the 1982 United Nations Convention on the Law of the Sea which adopts the 200 nautical mile Exclusive Economic Zone regime. Moreover, due to the notion of the outer limit of the continental shelf, the conflicts have developed into three dimensional ones in order to acquire more natural resources even in the seabed. To make matters worse, such three dimensional conflicts have expanded to the airspace as well. The paper will analyze what implications the sudden declaration of China's ADIZ have for the regional security in Northeast Asia from the perspectives of public international law. To this end, the paper 1) starts with the debates on the legal nature of the ADIZ, 2) identifies the Chinese government's political motives for the establishment of the ADIZ over the East China Sea, 3) assesses the responses of the regional States and the USA to the China's establishment of the ADIZ, and then 4) discuss what implications the overlapped ADIZ of the three key States in the region have for the regional security and stability.

• 설비공학논문집
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• 제26권7호
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• pp.335-342
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• 2014

The big issue in fire and life safety protection in atriums is that hot smoke can spread vertically via the atrium openings, and impact atrium floors remote from the fire. Three different strategies to provide fire and life safety protection for atrium space were evaluated in this study, using the FDS model. Strategy A is the atrium protection approach addressed in the Korean Building Fire Protection Code, where atria are required to be enclosed with fire shutters from the $2^{nd}$ floor to the atrium top, and the ground floor is allowed to open to the atrium; in this case, no smoke control is required. Strategy B is the atrium protection approach, with smoke control provided in accordance with NFPA 92B; in this case, no atrium floor is enclosed. Strategy C is the atrium protection approach, in which some of the upper atrium floors are enclosed (the case of the top atrium floor being enclosed is evaluated in this study), and atrium smoke control is also provided to protect the lower atrium floors.

• 설비공학논문집
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• 제20권2호
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• pp.97-105
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• 2008

This paper presents simulated and experimental test results of optimal control algorithm for an encapsulated ice thermal storage system with full capacity chiller operation. The algorithm finds an optimal combination of a chiller and/or a storage tank operation for the minimum total operation cost through a cycle of charging and discharging. Dynamic programming is used to find the optimal control schedule. The conventional control strategy of chiller-priority is the baseline case for comparing with the optimal control strategy through simulation and experimental test. Simulation shows that operating cost for the optimal control with chiller on-off operation is not so different from that with chiller part load capacity control. As a result from the experimental test, the optimal control operation according to the simulated operation schedule showed about 14 % of cost saving compared with the chiller-priority control.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.838-843
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• 2008

Cause of struggling to escape from dependency of fossil fuels, the fuel cell and the Plug-in Hybrid Electric Vehicle (PHEV) draw attention in the all of the world. Especially, the Polymer Electrolyte Membrane Fuel Cell (PEMFC) systems have been anticipated for next generation's energy supplying system, and we can predict the PHEV will enlarge the market share in the next few years to reduce not only the air pollution in the metropolis but the fuel-expenses of commuters. This paper presents simulation results about the strategy of smart charging system for PHEV in the residential house which has 1 kW PEMFC cogeneration system. The smart charging system has a function of recommending the best time to charge the battery of PHEV by the lowest energy cost. The simulated energy cost for charging the battery based on the electricity demand data pattern in the house. The house which floor area is $132\;m^2$ (40 pyeong.). In these conditions, the annual gasoline, electricity, and total energy cost to fuel the PHEV versus Conventional Vehicle (CV) have been simulated in terms of cars' average life span in Korea.