• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.689-696
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• 2000

In this paper, the cascaded co-channel interference canceller using the dead zone decision is proposed to reduced the co-channel interference in the DS/CDMA communication with the multipath fading and its performance is analyzed. The cancellation scheme creates the replica of the co-channel interference using the data decision of correlator output and removes it at the next stage. The canceller uses the dead zone decision which is detecting strong signal to obtain a good performance in the mobile communication. The results of performance analysis show that the proposed cancellation scheme has the improved performance and the number of user is increased 4 times compared with the conventional receiver, and increased 17% compared with the hard decision. And also the perfect power control is required along with increasing the number of user.

• Culinary science and hospitality research
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• v.16 no.1
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• pp.191-208
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• 2010

The hotel business should enhance a service quality in order to improve management skills and profits. However, when compared the size of foodservice industry and hotel, it is show that the hotel management systems are insufficient. In this respect, this study examines how the culture of hotel business affects to service quality. The results of the analysis are as follows. First, the culture of hotel business affects restaurant tendency. Consequently, the hotel, which is open-minded culture, copes with the external changes in a flexible manner. Second, the culture of hotel business affects hotel management skills. Good culture of the business creates the positive result toward the employees, customers, prime cost and inventory control. Third, hotel restaurant tendency affects to efficient hotel service quality and management performance. Fourth, change of hotel management skills brings difference of service quality and management performance. Good hotel management skills will be able to raise the competitive power between hotels. In the future, various empirical researches are continuously expected. By doing so, the result of the study helps to scholars and hotel managers.

• Journal of Drive and Control
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• v.12 no.1
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• pp.1-8
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• 2015

The stability of friction characteristics and thermal management for a dry type dual clutch transmission (DCT) are inferior to those of a wet clutch. Too high temperature resulting from frequent engagement of DCT speeds up degradation or serious wear of the pressure plate or burning of the clutch disk lining. Even though it is significantly important to estimate the temperature of a dry double clutch (DDC) in real-time, few meaningful study of the thermal model of DDC has been known yet. This study presented a thermal analytical model of lumped parameters for a DDC by analyzing its each component firstly. Then a series of experimental test was carried out on the test bench with a patented temperature telemetry system to validate the proposed thermal model. The thermal model, whose optimal parameter values were found by optimization algorithm, was also simulated on the experimental test conditions. The simulation results of DDC temperature show consistency with the experiment, which validates the proposed thermal model of DDC.

• Journal of the Korean Geographical Society
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• v.48 no.2
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• pp.218-238
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• 2013

The objective of my paper is to investigate historical change in concepts of medical geography and to present its historical vision. Modern medical geography was established in the name of medical topography in Europe where it had to control tropical diseases in the course of exploration and voyages for colonial interests. England developed medical geography in the name of sanitary reform, France did so for civilizing mission, and geomedicine prevailed in Germany. The twentieth century witnessed two traditions of medical geography, with focus on disease ecology and medical care system, respectively. In addition, the paper emphasizes the significance of cartography of disease as knowledge as power. As the identity of place becomes increasingly important in relation to health at the around of the twenty-first century, geography of health has emerged as a new promising discipline independently of medical and public health geography.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.10a
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• pp.322-323
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• 2015

Traditional rotation type large beacon was characterized by frequent failure, long repair time and high cost etc. These problems are caused by traditional light sources(metal halide lamps or tungsten halogen lamps). In order to solve these problems, IALA standards-based(efficiency and reliability) large LED beacon technologies are needed. we developed by applying a LED. The object of the this project, to design a reflective optics and the high power LED lighting engine module. And to develop a rotational speed control system for controlling flash pattern of beacon. As a result, to develop of LED beacon for landfall mark that distance to reach the light 20NM to 27NM.

• Journal of the Korean Institute of Gas
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• v.11 no.4
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• pp.54-58
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• 2007

The trailers with electronically controlled diesel engine was converted to dual fuel engine system. To estimate economical efficiency, test vehicles have been operated on a certain driving route repeatedly. Fuel economy, mximum driving distance per refueling and driveability are examined on the road including a free way. Developed vehicle can be operated over 500 km with dual Hel and shows 85% of diesel substitution ratio. Driveability is similar with but passing acceleration. It will be improved by calibration process. Test engine was set up for investigating power output, thermal efficiency and emission. ND 13-mode tests were performed for the test cycle. The emission result of dual fuel meets K2006 regulation and the engine performance of dual fuel engine was equivalent to the performance of diesel engine.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2336-2338
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• 2000

고효율, 무공해의 신발전 기술인 연료전지 발전은 발전 용량 및 스택구성에 따라 차이가 있으나 기본적으로 저전압, 대전류 특성과 부하에 따라 발전 전압이 크게 변동하는 특성을 갖는 직류전원으로써 이를 상용으로 이용하기 위해서는 연료전지 발전 전력을 안정된 전력으로 변환하여 주는 장치가 필요하며, 이러한 전력 변환장치가 연료전지 발전의 최종 출력 전원의 질을 결정한다. 연료전지 전력변환장치는 전압조절기능, 승압 기능을 가져야 하고, 연료전지 본체와 부하를 안정하게 운전하기 위해 전력변환장치 뿐만 아니라 부하와 연료전지 본체의 운전상태 감지 기능, 각종 장치의 보호와 제어기능을 가져야 한다. 본 논문의 목적은 자동차용 연료전지 출력 전력변환장치의 종합제어장치의 설계를 위해 연료전지 스택시뮬레이터를 개발하는 것이다. 연료전지 스택 시뮬레이터는 연료전지 발전 특성과 일치하는 전력을 출력해 주는 직류전원 공급장치로써 이를 이용하여 연료전지 출력 전력변환장치의 종합제어장치를 충분한 예비실험과 수정, 보완함으로써 연료전지용 전력변환 시스템의 성능개선, 안정성 향상 등을 가질 수 있다.

• The Journal of the Acoustical Society of Korea
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• v.33 no.2
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• pp.111-117
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• 2014

In this paper, the structure-borne noise reduction on electrical equipment is discussed by the experimental analysis. The water cooling system in electrical equipment is the only noise source, so the mock-up was made to measure noise characteristics. Effects of power supply, stiffness, isolation of noise source and natural frequency determined by resilient mounts are investigated using the mock-up. The console prototype was made referring to noise reduction technique by the mock-up. The structure-borne noise level of a console prototype was measured and some experiments to reduce the noise was undertaken. The $1^{st}$ and $4^{th}$ harmonics of operating frequency of cooling fans causes highest structure-borne noise levels. The control of operating speeds of several DC cooling fan groups was tried. Also types and installation layouts of resilient mounts were investigated. To reduce structure-borne noise, followings can be applied: increase of stiffness, isolation of source, decrease of natural frequency of mount, combination of operating speed of fans, selection of mounts, and so on.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.5
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• pp.37-43
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• 2009

Streaming video service over wireless and mobile communication networks has received significant interests from both academia and industry recently. Specifically, mobile WiMAX (IEEE 802.16e) is capable of providing high data rate and flexible Quality of Service (QoS) mechanisms, supporting mobile streaming very attractive. However, we need to note that streaming videos can be partially deteriorated in their macroblocks and/or slices owing to errors on OFDMA subcarriers, as we consider that compressed video sequence is generally sensitive to the error-prone channel status of the wireless and mobile network. In this paper, we introduce an OFDMA subcarrier-adaptive mobile streaming server based on cross-layer design. This streaming server system is substantially efficient to reduce the deterioration of streaming video transferred on the subcarriers of low power strength without any modifications of the existing schedulers, packet ordering/reassembly, and subcarrier allocation strategies in the base station.

• Journal of National Security and Military Science
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• s.4
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• pp.119-156
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• 2006

Now it is not useful the theory about civil-military relationship that have been analysed for power games between military and civilians Korean society is going on governance society managed by cooperating network of government, civilian society and business market These social change require for new context about civil-Military relationship. Military leadership must contribute desirable civil-military relationship This study will suggest the direction about military leadership for desirable civil-military relationship. Now political issues about military intervention to the government are almost settled, but the worry about complications between military and civilians exist in the part of low issues like policy-making. Another important issues is military leadership about the style of social-being. In recent years, social change is very complex and speedy like global networking and diversity, leadership environment also, changed like leadership paradigm shift. Military leadership must be examined from the principle to the context of social integration At the present age, individual soldier is citizen in uniformed. Also military leadership must to seek the principle in the citizen mind like citizenship. Another charactristics of present day military is influence of high technogy. For the high-tech war military need the transition about science and technology from the whole society. In the context of above the development of military leadership are suggested as follows. First, the development of military control leadership must besought to the context of cooperation between government and military. Government must provide the system to strengthen military professionals in the process of policy-making about national security Second, military leadership must embody the important social values through the advanced military making, Third, military leadership must provide the adaptability to the society through the military education of their soldiers Forth, military leadership must be contributed to the social integration and to the growing up individual soldiers like their socialization and their achievement. Five, an important subject of military leadership is the creation of desirable military culture through the harmony of social culture and military culture.