• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8A
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• pp.743-751
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• 2010

OFDMA femtocell becomes an effective solution to support indoor high data rate services instead of the macrocell systems. Although the advantage of the femtocell, the co-channel interference between the femocell and the macrocell is the most significant problem that reduces the system performance. Macrocell users who have no permission to access the femtocell suffer from interference of the downlink transmission of femtocell. Therefore, the femtocell should use transmission power as small as possible to reduce interference to macrocell users. In this paper, we define the margin adaptive power allocation problem for the femtocell and propose a heuristic power allocation algorithm to solve the problem. Simulation results show the performance of the proposed algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.374-377
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• 2012

GNSS(Global Navigation Satellite System) based land transportation infrastructure system is consists of receiving station and central station. The functions of the central system include receiving station's data gathering and decoding, carrier correction and integrity information generated, transmission of data in real-time. In general, The central station architecture should take into account various important points relating to hardware/software of system, data archiving and checking, availability and continuity of operation, etc. There is a fundamental need for a generic design capable of being used in any situation. Also, There is need to develop an expandable and interoperable central station architecture. In this paper, the process of design and manufacture and verification will be introduced.

• Proceedings of the Fisheries Business Administration Society of Korea Conference
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• 2005.11a
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• pp.29-50
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• 2005

EU는 세계 3위의 어업생산지역임에도 불구하고 가공어류와 양식수산물에 대한 세계 최대의 소비시장을 가진 탓에 만성적인 수산물 공급부족을 겪고 있다. 이에 따라 EU는 일찍부터 제3국과의 어업협정을 통한 원양어장 진출을 적극적으로 추진해 왔다. EU의 원양어장 진출정책을 시기별로 분류하면 1세대 유형에서부터 4세대 유형으로 구분가능하다. 수역별로는 크게 유럽북부와 남부수역으로 분리되어 있으나, 어업협정 유형으로는 북유럽형, 발틱형, 북미형, 중남미형, 그리고 ACP형으로 세분화 할 수 있다. EU는 특히 대부분의 쌍무어업협정을 아프리카, 인도양, 서태평양 연안국들과 맺고 있어, 이들 국가와의 쌍무적 어업관계가 EU 원양어업정책에 있어 매우 중요하다. 최근 원양어장의 자원부족현상이 점차 심각해짐에 따라 EU 위원회는 그들의 공동어업정책 개혁안에 제3국과의 어업협력강화 방안을 수립하였다. 이는 연안국과의 어업관계를 단순입어에서 동반자적 입어관계로 발전시키는 한편, 어업 외적인 부문의 협력을 포함하는 포괄적 접근 정책을 추진하고 있다. 이러한 EU의 움직임은 단순한 어획쿼터할당에 대한 입어료지급 방식은 조업국과 연안국 간의 신뢰관계 증진에 그다지 도움이 되지 못한다는 것을 의미한다. 따라서 조업국은 연안국에 대한 자원관리기술을 지원해 주고, 자원평가에도 공동으로 참여함으로써 양국간 협력적 수산자원관리정책을 지향하도록 하여야 한다는 것을 시사하고 있다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9A
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• pp.1348-1358
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• 2000

The paper contributes to a traffic analysis for the CDMA cellular base station with repeater which are operated in a cell site. Usually the repeaters' traffic of the CDMA cellular system hardly could be separated from that of the base station because the links of the repeaters are divided from RF circuits of the base station. The paper introduces a traffic measuring method that separates the traffic of repeaters from that of the base station using time delay device. To get general results we use a single BTS(Base station Transceiver Subsystem) with three repeater as well as a single BTS with a single repeater. Then we proved that the traffic of the repeaters could separate from that of the base station clearly.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.157.1-157.1
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• 2012

1990년대 제안된 RTK(Real-Time Kinematics)는 GNSS/GPS 반송파 위상(carrier phase) 관측값을 이용한 방식으로 cm 수준의 정확도를 실시간으로 산출할 수 있어 측지 측량 등 다양한 분야에서 활용되고 있다. 그러나 한 가지 중요한 단점은 이 방식을 사용하는 기준국과 사용자는 10~20km 이내에 존재해야만 빠르고 신뢰할 수 있는 해를 산출할 수 있다는 점이다. 이는 궤도오차, 대류층 및 전리층 오차에 공간 상관성(spatially correlated) 있기 때문인데, 사용자 주변을 둘러싼 다중 기준국들의 측정치를 조합하여 보상하거나 모델링하여 줄이는 방식인 다중 기준국 네트워크 기반의 RTK 알고리즘이 제안되어 사용되고 있다. 다중 기준국 네트워크 기반의 RTK 프로세스에서 기준국간 미지정수 결정은 전 과정의 핵심 프로세스라고 할 수 있으며, 관련되어 많은 기술들이 제안되고 연구되어 왔다. 특히, 1980년대 말부터 현재까지 후처리 기반으로 꾸준하게 연구되고 있는 Blewitt에 의해 전리층 제거 조합과 Wide-lane 반송파 위상 조합을 활용한 미지정수 검색 방법이 대표적이며 이후에도 Gao, Colombo등 다양한 연구자에 의해 활용되었다. 이 연구에서는 실시간으로 다중 기준국 반송파 미지정수를 결정하는 기술에 대한 연구를 수행하였다. L1, L2 관측값 조합으로 인한 관측값의 잡음 수준이 증가하는 영향을 피하기 위해 L1, L2 반송파 위상 및 의사거리를 그대로 관측값으로 사용하여 사용자 위치 및 속도, 기준국간 이중 차분된 전리층 지연 수직성분, 대류층 wet 지연 수직 성분, 이중 차분된 미지정수를 미지의 상태변수로 확장 칼만필터를 통해 직접적으로 추정하는 방식으로 미지정수의 실수해를 결정하였고, 정수해는 실시간에 적합한 MLAMBDA 기법과 비율테스트를 통한 정수해 검정기법을 통해 결정하였다.

• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.7-16
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• 2008

The immigration procedure at airports is vital to making passenger and cargo transport faster. The rapid procedure of immigration could be an important determining factor when passengers select an air transport company, one that should have high satisfactory in terms of their service level and efficiency. Therefore, the advanced airport makes it easy for customers and their cargo to proceed. The coordination between authorities related to the Korean international airport is not satisfactory for customers. This paper analyzes the factors necessary to enhance the airport immigration procedure with the movement of aircrafts, passengers, cargo, and post, using the CK(Cook and Kress) model of DEA(Data Envelopment Analysis). From this study, the author found that research and development will be needed to improve the immigration procedure, especially on facilities and their operating systems. There are needed, also, performance indicators and a continuous monitoring system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.9
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• pp.1696-1703
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• 2016

In this paper, it verifies site environment aspect that NDGPS (Nationwide Differential Global Positioning System) operated by MOF (Ministry of Oceans and Fisheries) will be used as the same site of reference stations for SBAS (Satellite Based Augmentation System). In order to prove this feasibility, we analyze the site environment requirements for SBAS reference stations, as well as we establish the procedure for the verification of the site environment requirements. With this procedure of the site environment survey, we perform site survey in the real field and analyze the results. We select interim candidate sites for survey which currently operating 17 NDGPS reference stations. This paper could be utilized in the process of selection or installation of reference stations in the field of GNSS(Global Navigation Satellite System) and the drawing the consideration which NDGPS reference stations will be co-operated as SBAS reference stations.

• Microbiology and Biotechnology Letters
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• v.8 no.4
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• pp.247-253
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• 1980

This experiment was carried out to improve the method of koji preparation by using stainless steel frays which were specially designed and covered with lids. To elucidate changes in chemical composition and formation of enzymes during the preparation of koji with glutinous rice for red pepper paste. professes, amylases, reducing sugars, nitrogens, and microbial contaminations were determined and compared with the case of using trays without lids. The results obtained were as follows. 1. The activities of protease and amylases (both liquefying and saccharifying activities) during the koji preparation were found to be higher incase of using the trays with lids than that without lids. 2. The contents of moisture, soluble nitrogen, amino nitrogen, and reducing sugar were also higher in case of using the trays with lids. 3. Contamination by yeasts and bacteria were markedly low in the trays with lids. 4. Temperature of koji was higher in the trays with lids, however the level of moisture loss was 1ower.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.507-511
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• 1994

Traditional and commercial soy sauces used for seasoning soups and cooked mungbean sprouts were evaluated for consumer preference. Table salt was included in sensory tests, because the consumer commonly used it for seasoning soups. Triangle tests with 30 trained panelists were used to evaluate differences between two soy sauces, and 9 point hedonic scale tests with 100 consumer panelists to evaluate the consumer preference. Taste of sea mustard, Chinese radish and dried pollack soups seasoned with the traditional soy sauce, commercial soy sauce for soup and table salt was significantly different. The consumer panel indicated that the commercial soy sauce for soup was most preferred and the traditional soy sauce least preferred. Taste of cooked mungbean sprouts seasoned with two sauces, prepared with either traditional or commercial soy sauces, was significantly different from each other, but the consumer panel could not detect the difference in preference.

• Journal of the Economic Geographical Society of Korea
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• v.6 no.2
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• pp.355-375
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• 2003

Since the mid 1980s, the emergence of the Newly Industrialized Countries has been the most remarkable mutation in the foreign direct investment. This emergence is creating the new international spacial flows constituted by the developed country, the newly industrialized country and the developing country. According to the active foreign direct investment of the Asia Newly Industrialized Countries (ANICs) into East Asia from the middle of the 1980s, the intra-East Asia direct investment flow has a observable structure hierarchic composed of Japan, ANICs, ASEAN and China. In the inflow of intra-East Asia direct investment, Japan and ANICs flows from the extra-developed country and Japan, AESAN from ANICs, Japan, and China from the ANICs. In the outflow, Japan flows relatively into the ANICs and ASEAN, ANICs into ASEAN and China, ASEAN and China into the ANICs. In conclusion, the emergence of ANICs and theirs role intermediate in the East Asian economy causes the intra-East Asia direct investment flows to make a hierarchical structure.