• Journal of Information Technology Applications and Management
• /
• 제9권4호
• /
• pp.13-34
• /
• 2002

This paper considers a postal transportation planning problem in the transportation network of the form of hub and spoke Given mail sorting centers and an exchange center, available vehicles and amount of mails to be transported between mail sorting centers, postal transportation planning is to make a transportation plan without violating various restrictions. The objective is to minimize the total transportation cost. To solve the problem, a tabu search algorithm is proposed. The algorithm is composed of a route construction procedure and a route improvement procedure to improve a solution obtained by the route construction procedure using a tabu search. The tabu search uses the best-admissible strategy, BA, and the first-best-admissible strategy, FBA. The algorithm was tested on problems consisting of 11, 16 and 21 mail sorting centers including one exchange center. Solutions of the problems consisting of 11 mail sorting centers including one exchange center were compared with optimal solutions On average, solutions using BA strategy were within 0.287% of the optimum and solutions using FBA strategy were within 0.508% of the optimum. Computational results show that the proposed algorithm can solve practically sized problems within a reasonable time and the quality of the solution is very good.

• 한국항공운항학회지
• /
• 제22권4호
• /
• pp.15-24
• /
• 2014

Low Cost Carrier(LCC)s in Asia Pacific market are expected to record high growth due to the expansion of Open Sky Policy among Korea, Japan, China and South East Asia. As everybody is aware of, LCC is not only saving flight cost but also creates differentiating business model by reducing unnecessary services such as F&B and in-flight duty free sales services. Booming LCCs in Asian market will cause not only Incheon airport but also other local airports in Korea to compete heavily to attract LCCs. For example, Air Asia Group with more than 200 fleet has expanded its alliance network throughout Asia. Therefore this paper has researched a new business model operating a LCC terminal for the hub airport competitiveness. According to analysis result of case study, it was found out, considering increasing airline demand next decade, Incheon airport and other domestic airports in Korea had better change an existing terminal into a LCC Terminal(LCCT) to differentiate airport services and expand its hub network. That is because of economic feasibility, first of all, of securing hub and spoke networking capabilities with airlines and finally of developing commercial facilities customizing LCC passengers' demand.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2009년도 공동학술대회
• /
• pp.192-193
• /
• 2009

세계 항만환경은 초대형 컨테이너선의 등장이후, 허브 & 스포크(Hub & Spoke)의 형태로 급속히 변화하고 있다. 이에 해외 선진항만들은 중심항만으로서 자리매김하기 위해 자동화 컨테이너터미널을 구축하는 등 생산성 향상을 위한 노력을 하고 있으나, 국내의 경우 자동화 컨테이너터미널에 관한 연구, 그중 자동화 게이트시스템에 대한 연구는 상대적으로 미흡한 실정이다. 본 연구에서는 자동화 게이트시스템을 구축 시, 최적 기술 대안을 선정하기 위해 국내 외 게이트 운영현황과 관련 기술들의 분석함으로써 자동화 게이트시스템 구축 시 필요한 기술을 도출하다. 그 결과를 컨테이너터미널 운영사의 기술 담당자들을 대상으로 현재 게이트시스템의 만족도와 문제점 그리고 향후 게이트시스템 구축 시 사용하고자 하는 기술과 기대효과를 찾고자 하였다. 하지만 1차 설문결과 내용만으로는 어떤 요소 기술이 사용자가 요구하는 기대효과를 만족시킬 수 있는 최적 기술 대안인지 제시하기 힘들었다. 이를 보완하기 위한 방법으로 정성적인 주관적 평가요소를 객관화하여 각 평가기준에서 나타나는 적용상의 한계를 해결할 수 있는 방법인 AHP 기법을 활용하였으며, 최종적으로 생산성 보안성, 경제성 3가지 평가 기준을 고려하여 최적 기술 대안을 선정한 결과 RFID가 최적의 기술대안으로 평가되었다.

• Journal of Magnetics
• /
• 제21권4호
• /
• pp.561-569
• /
• 2016

Although pretty methods have been proposed to reduce torque ripple, they generally suffer from the decreased torque density. This paper will investigate the spoke-type interior permanent magnet (IPM) machine with shaping methods, including the sinusoidal (SIN), the inverse cosine (ICS), the sinusoidal with third harmonic (SIN+3rd), and the inverse cosine with third harmonic (ICS+3rd). In order to obtain low torque ripple and high torque density, the shaping method applied in rotor and stator at the same time, termed as the dual-shaping method, is proposed. This method is analytically derived and further confirmed by finite element method (FEM). It turns out that the ICS and ICS+3rd shaping methods are more suitable for outer rotors, while the SIN and the SIN+3rd shaping method should be used in inner stators. The original machine, the singular shaped machines and the dual-shaped machines on electromagnetic performances are compared for evaluation. The results verify that the dual-shaping method can improve torque density, whilst reducing torque ripple.

• 한국항공운항학회지
• /
• 제32권1호
• /
• pp.79-90
• /
• 2024

UAM is emerging due to the deepening population concentration in the metropolitan area and the problem of congested ground transportation in urban areas. Accordingly, along with research on eVTOL aircraft for UAM services, interest in vertiport, the interest in vertiports, the infrastructure that allows eVTOLs to take off and land, is also increasing. However, behind the concentration of population in the metropolitan area, aphenomenon of local extinction is occurring in conjunction with the aging population. AAM, which moves quickly through 3D space, can be an effective SOC facility in times of local extinction crisis. In this paper, we introduce a design plan from the perspective of a complex transper center for a regional hub-level vertiport that can connect with local high-speed rail and utilize local airports in compliance with the vertiport design guidelines issued by FAA(Federal Aviation Administration) and EASA(European union Aviation Safety Agency). We would like to present Vertiport's future operation plan.

• 한국경제지리학회지
• /
• 제13권2호
• /
• pp.181-195
• /
• 2010

광역경제권 정책에 따라 산업단지 정책도 광역권 단위에서 연계구조를 구축하려는 방향으로 논의가 진행되고 있다. 본 분석의 목적은 수도권 산업단지들을 대상으로 산업단지간 연계구조를 도출하는 것이다. 먼저 수도권 산업단지 입주업체 설문조사를 실시하여 광역권 내의 지역간 연계 현황을 파악하였다. 산업단지의 업종별 종사자수 자료를 이용하여 산업단지간 구조유사척도를 계산하고, 수도권 내부와 외부 산업단지의 유사성을 살펴보았다. 또한 산업단지간 거리, 업종별 비율, 입지계수 등의 지표를 종합적으로 판단하여 산업단지 허브-스포크 연계구조(안)를 도출하였다.

• 대한치과보철학회지
• /
• 제26권1호
• /
• pp.31-49
• /
• 1988

This study was performed to investigate the sound distortion following the alternation of the palatal plate thickness, for this study, 3 subjects who were born in Seoul and spoke Seoul dialect were recruited from K university male student population. First, their sounds of /아(a)/, 어(e)/, 오(o)/, 우(u)/, 으($\.{+}$), 이(i)/,에(e)/ without inserting plate were recorded , and then the sounds with palatal plates of different thickness were recorded, respectively. The palatal plates was constructed to cover the alveolar & palatal surfaces of the maxilla with an approximate thickness of 1.0mm, 2.5mm, and thickness of 2.5mm over the alveolar ridge & 1.0mm elsewhere and, named B, C, D-type, in succession. Series of analysis were administered through Computer (16 bit IBM PC/AT) at analyze the sound distortions. These experiments were analyzed by the LPC, Log Area Ratio. The findings led to the following conclusions: 1. Sound distortions were relatively minute in each condition and informations, however, /이(i)/ was the most distorted vowel in all conditions. 2. By and large, sound distortion was large in C, D-types. However, there was no correlation of the distortion rate on the 3 informants, and all tested vowels. 3. It was similar to LPC, Log Area Ratio distortion rates. 4. It was found that the sound distortion wit]1 plate inserted was verified to the numeric value with LPC and Log Area Ratio method.

• 디자인학연구
• /
• 제16권3호
• /
• pp.371-380
• /
• 2003

현대 소비자들은 좀더 감각적이고, 정서적 만족감을 제공하는 제품을 기대하고 있으며, 이에 감성공학이란 전문적인 지식들을 자동차 디자인에 응용할 필요성이 대두되게 된 것이다. 자동차의 경우 개성 있는 나만의 차를 갖고 싶어하는 욕구로 자동차를 꾸미는 데에 많은 투자를 하면서 휠 디자인이 중요시되고 있다. 이에 본 연구에서는 새로운 디자인 방향 모색으로 감성 공학적 분석 방법을 통하여, 소비자들의 자동차 휠 디자인에 대한 이미지를 파악하고, 소비자의 요구와 감성에 따른 자동차 휠 디자인을 분석하였다. 그 결과, 'harmonious', 'fresh'와 'strong'의 이미지가 자동차 휠 디자인을 대표하며, 'harmonious' 이미지로는 스포크 타입, 'fresh'의 이미지는 메쉬 타입, 'strong'의 이미지는 디쉬 타입의 자동차 휠 디자인으로 나타났다. 따라서 자동차 휠의 디자인 개발에 소비자의 감성을 기반으로 한 감성 공학적 디자인 접근을 함으로써 소비자에게 만족시킬 수 있는 디자인 방향 제시를 가능케 하였다.

• Strategy21
• /
• 통권32호
• /
• pp.160-191
• /
• 2013

This article is focused how the maritime strategy between continental powered country(the Soviet, the China) and maritime powered country(the U.S.) interact with attack and defense theory. We will know, what is the maritime strategy that the U.S. of military superiority has pursued with the point of view of attack, on the other hand, relatively what is the maritime strategy that the Soviet-Sino of military inferiority has pursued with the point of view of defense. In cold war, the Soviet has counteracted to 'blue belt defense' in active defense as to the U.S. 'sea strike' and in post cold war, the China counteract to 'A2/AD' as to the U.S. 'Air-Sea Battle'. The difference between the Soviet-Sino maritime strategy is that the China has emerged the second an economic power and their leadership has a strong's will to strengthen their navy's power. although the U.S. declare the pivot to Asia, the influence on Asia of the U.S. tend to decrease because of sequest. therefore, the China will seek to the more active defense beyond the first island chain. Meanwhile, the U.S. has reinforced of 'hub and spoke strategy' to solidify the U.S. formal allies to band together regional powers and to overcome the A2/AD challenge, the U.S. has been developed that the Air-Sea Battle concept meshes with Washington's 'rebalancing' policy toward the Asia-Pacific as its vital missions to safeguard core island or semi-island allies-namely, Korea and Japan-and crucial sea lanes of communication in the region are conducted mostly from or over the sea.

• 품질경영학회지
• /
• 제45권1호
• /
• pp.129-138
• /
• 2017

Purpose: This research aims to analyze the service process of corporate courier services in order to offer service providers possible directions for adaptation of new technologies and assurance of better quality services. Methods: Through the analysis on the parcel service process of company Y by applying service blueprinting method, the overall process and failure service points of corporate courier services can be recognized and investigated. Next, the several newer technologies, augmented reality glasses, exoskeleton, and drone are applied to the service process of company Y as they are suggested by the literature review and referenced to DHL's report on the Fourth Industrial Revolution. Then, service options to overcome the service failure points to improve the service process can be produced. Results: The parcel service process of the company Y is utilized as a hub-and-spoke structure by having distribution and delivery centers which separates customers into two types, ones using the total services and the others only using the delivery service. In addition, the main cause of the service failures is determined that it is due to the limited working hours of delivery centers compared to the workload. Conclusion: This research contributes in better understanding of corporate courier services and providing information for benchmarking. An empirical research on the costs and the efficiencies of applying the new technologies is suggested for the further improvement in the processes of corporate courier services.