• Title/Summary/Keyword: Port Cluster

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A Study on the Ka-Band Satellite Output Power Control Technology (Ka 대역 위성 출력 전력 제어 기술 연구)

  • Shin, Dong-Hwan;Yun, So-Hyeun;Moon, Seong-Mo;Lee, Hong-Yeol;Eom, Man-Seok;Yom, In-Bok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37B no.11
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    • pp.1072-1081
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    • 2012
  • For Ka-band satellite communication system, a new flexible payload technologies which can compensate rain attenuation have to be developed. The Ka-band satellite output power control technology enables to adjust downlink output power of satellite payload in Ka-band (19.8 ~ 22.2 GHz). In this paper, we introduce multi-beam antenna with multi-port amplifiers for Ka-band flexible output power allocation system. We have designed multi-beam antenna with array-fed reflector to form 8 beams on the Korean Peninsula. The target EIRP per beam is more than 59 dBW. The system is designed to present 6 dB boost beams for rainfall areas. Individual beams were optimized by the excited amplitude and phase of feed elements of the feed cluster. The multi-port amplifier(MPA) is one of effective approaches for flexible power allocation in combination with multi-beam antenna. In case of using MPA in multi-beam system, the inter-port isolation characteristic of MPA is important parameter to avoid interference among the output ports. In this paper, we propose a new MPA structure that consists of two $4{\times}4$ Buttler matrixes and phase/amplitude controllable power amplifier modules.

An Analysis on the 500m - Mesh Classification based on the Heat Consumption Density in Busan (부산시 500m 메시 레벨에서의 에너지소비량 분포 분석)

  • Hwang, Kwang-Il;Choi, Duk-In;Kim, Da-Hye;Yang, Ing-Chan;Yoon, So-Ra
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2010.04a
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    • pp.193-194
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    • 2010
  • This study classify the every meshes in Busan metropolitan city, based on the heat density and cooling/heating ratio. As the result of evaluations on the heat density and cooling/heating ratio for the 3289 meshes, the number of meshes which needs more than 2.5 Tcal/mesh.year of heat density is 850(25.8%). The meshes that needs more than district and cooling index 1, which is normally and strongly requested to introduce the district cooling and heating system, is 188(5.7%).

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A Study on the Effects of Industry Types and Business Characteristics on Management Performance: For Japanese Logistics Companies (물류기업의 업종과 사업특성이 경영성과에 미치는 영향에 관한 연구 -일본 물류기업을 대상으로-)

  • Koo, Kyoung-Mo
    • Journal of Korea Port Economic Association
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    • v.34 no.2
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    • pp.51-68
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    • 2018
  • This paper compares the differences in management performance in the logistics market and analyzes the differences in business characteristics depending on the industry types. In addition, the effects of industry types and business characteristics on management performance are examined. The analysis method used is ANOVA and K-means clustering. The implication of the study are as follows. First, in the logistics market in Japan, there was a difference in management performance among the types of industry. The warehousing service type had the highest profitability and stability among all the industry types. Second, differences in business characteristics by industry types were tested. It was found that offshore cargo transportation type was more capital intensive than the other types. In addition, warehousing service type had higher business leadership and credit transaction than others. Third, industry types and clusters based on business characteristics had a significant impact on management performance through interaction effects. For the profitability variables in detail, other clusters had a significant effect between transportation types(onshore and offshore cargo) and warehousing service type. On the other hand, in stability variables, one cluster was effective in all types, which is a characteristic that lowers both capital intensity and business leadership.

A Study of Marketing Strategies according to the Criteria of Users' Choice in Pallet Pool Services : Focused on Mettroporitan Seoul Area Warehouse Companies (파렛트 풀 서비스의 효익세분화에 따른 마케팅 전략에 관한 연구 - 수도권 창고업체들을 중심으로 -)

  • Choi, Se-Kyung;Park, Mu-Il;Lee, Kang-Dae
    • Journal of Korea Port Economic Association
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    • v.25 no.3
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    • pp.1-20
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    • 2009
  • A survey to pallet users was conducted in an aspect of the efficiency and benefit. The questionnaire identified the preference about the main variables such as price, size, conformity, material, which are the criteria of the users' choice. staffs in the capital region was selected as respondents and Cluster Analysis and Simulations was carried out with Conjoint Analysis. The result shows that the variables of material and conformity between facilities and products were more important than the variable of size. The respondents prefer the pallets with a various range of products because warehouses should keep a range of products under various condition of temperature. In accordance, the companies that provide a pallet pool service should set up individual marketing strategy by a type of customers so as to maximize the competitiveness in domestic or international markets. Furthermore, supplying standardized pallets should be consistent with the standardization not for individual logistics units, but for whole logistic systems. To achieve this, it requires the compatibility amongst a range of logistics activity participants by their characteristics.

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Spatio-temporal Variation and Evaluation of Benthic Healthiness of Macrobenthic Polychaetous Community on the Coast of Ulsan (울산 연안 해역 저서다모류 군집의 시·공간 변동 및 저서건강도 평가)

  • Jeong, Bong Geun;Shin, Hyun Chool
    • Ocean and Polar Research
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    • v.40 no.4
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    • pp.223-235
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    • 2018
  • This study was carried out to investigate benthic sedimentary environments and benthic polychaetous communities on the coast of Ulsan, located on the southern East Sea of Korea. This survey was conducted at 15 stations, four times seasonally in January, April, July and October 2016. From the coast to the outer sea, surface sediments turned into fine grained sediments. There were complex coarse-grained sedimentary facies in various forms in the coastal zones while those with mud facies were found in the offshore zone. Organic matter content (LOI) and sulfide amount (AVS) recorded extremely high values, and increased from the coast to the outer sea, showing a similar trend to mud content with depth. The benthic polychaetous community revealed a mean density of $525ind./m^2$, and the total species number of species was 84. The major dominant polychaetous species were Magelona japonica, Lumbrineris longifolia and Heteromastus filiformis throughout the four seasons. Magelona japonica was concentrated predominantly in shallow coastal areas, but was present in all the regions of the survey area. Lumbrineris longifolia showed higher density in offshore regions more than 30 m deep, whereas H. filiformis showed higher density in coastal areas less than 30 m in depth. As a result of cluster analysis, the study area was divided into three ecological areas according to species composition, such as the northern coastal area between Ulsan PortOnsan Port, the southern area around Hoeya River and the outer sea area. Benthic environments in the study area, as determined by AMBI and BPI index, maintained a healthy condition in all four seasons with the AMBI at a level above GOOD and BPI at a level above FAIR. As organic matter accumulation continues to take place in the Ulsan coastal area, it is essential that detailed research activities continue to be carried out and ongoing monitoring be maintained.

The Spatial Growth Pattern of Korean Small-Medium Size Port and its Implications (우리나라 중소 무역항의 성장 패턴과 유형별 시사점)

  • Lee, Jung-Yoon;Ahn, Jae-Seong
    • Journal of the Korean association of regional geographers
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    • v.22 no.4
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    • pp.792-808
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    • 2016
  • Due to the high importance of foreign trade in the national economy, Korea has a lot of ports designated as trade ports compared to the small land size. However, because of the poor utilization results, some small trade ports have been criticized for wasteful financing due to redundant investment in SOC. This is because the characteristics and comparative advantage of foreign trade in trade ports have not been analyzed in detail by region. Therefore, this study analyzes the patterns and types of change in the size of trade, number of cargo items handled, and the number of trade target countries in the past 20 years for 19 domestic small trade ports using the time-series cluster analysis technique. As a result of analysis, Korean small trade ports were classified into five growth pattern types according to the analysis index, and characteristics and implications for each type could be derived. Today, as the foreign trade environment changes drastically and the importance of balanced regional development is emphasized, it is very important to study the growth types and implications of small trade ports and the results of this study are expected to provide meaningful implications for regional port development and operation in the future.

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The Busan Financial Center: Evaluation and Future Direction (부산금융중심지에 대한 평가와 향후 과제)

  • Lee, Ho-Sun
    • The Journal of the Korea Contents Association
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    • v.16 no.8
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    • pp.10-19
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    • 2016
  • In this paper, I evaluate national and regional policies for financial centers and Busan Fiancial Center and find the way of the future development of Busan Financial Center. And I found that national policies for financial centers was focused on general improvements of financial industry, so a little tasks for Busan Financial Centers were listed. Therefore I suggest that central government should have more national policies for enhancing Busan Financial Center and promoting participation of private financial firms. And I propose the broader incentive schemes for financial firms moving to Busan, and expect that combining national deregulation policies like Regulation-Free Zone and Regulatory Sandbox and Moonhyun-North Port financial free zone and FinTech cluster plans of Busan will make a big progress of Busan Financial Center.

High-Frequency Flyback Transformer Linked PWM Power Conditioner with An Active Switched Capacitor Snubber

  • Mun, Sang-Pil;Kim, Soo-Wook;Joo, Seok-Min;Park, Young-Jun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.7
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    • pp.7-15
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    • 2008
  • A single active capacitor snubber-assisted soft-switching sinewave pulse modulation utility-interactive power conditioner with a three-winding flyback high frequency transformer link and a bidirectional active power switch in its secondary side has been proposed. With the aid of the switched-capacitor quasi-resonant snubber cell, the high frequency switching devices in the primary side of the proposed DC-to-AC sinewave power inverter can be turned-off with ZVS commutation. In addition to this, the proposed power conditioner in the DCM can effectively take the advantages of ZCS turn-on commutation. Its output port is connected directly to the utility AC power source grid. At the end, the prototype of the proposed HF-UPC is built and tested in experiment. Its power conversion conditioning and processing circuit with a high frequency flyback transformer link is verified and the output sinewave current is qualified in accordance with the power quality guidelines of the utility AC interactive power systems.

Design and Implementation of Content Switching Network Processor and Scalable Switch Fabric

  • Chang, You-Sung;Yi, Ju-Hwan;Oh, Hun-Seung;Lee, Seung-Wang;Kang, Moo-Kyung;Chun, Jung-Bum;Lee, Jun-Hee;Kim, Jin-Seok;Kim, Sang-Ho;Jung, Hee-Jae;Hong, Il-Sung;Kim, Yong-Hwan;Lee, Yu-Sik;Kyung, Chong-Min
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.3 no.4
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    • pp.167-174
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    • 2003
  • This paper proposes a network processor especially optimized for content switching. With 2Gbps port capability, it integrates packet processor cluster, content-based classification engine and traffic manager on a single chip. A switch fabric architecture is also designed for scale-up of the network processor's capability over hundreds gigabit bandwidth. Applied in real network systems, the network processor shows wire-speed network address translator (NAT) and content-based switching performance.

Spatial Structure of Hinterlands and Forelands of Pusan Container Export Port: the Cases of 3 National Flag Carriers (부산 컨테이너 수출항의 배후지와 지향지의 공간구조)

  • Cho, Su-Kyung
    • Journal of the Korean Geographical Society
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    • v.28 no.3
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    • pp.247-267
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    • 1993
  • According to developing international economy since the World War II, the increase and competition of the national business is so empha-sized tht both the interest and the necessity about marine transportation playing the impor-thant role of international transportation are increased. Today, the container transportation, as called the innovation of marine transport has been prevailed since the 1970's. The purpose of this paper is to grasp the spatial structure of the hinterlands and forelands, its object is export container cargo at Pusan Export Port, as known for the transportation node of modern containerlization. In this study, for the purpose of grasping the relation between hinterlands and forelands of Korean export container cargo, first, I researched the transition of carloading about container cargo, the bistribution channel of cargo, the change of the items of container and the carlo-adings about transport route, secondly, I used the cluster analysis so as to group hinterlands according to the items of goods and forelands. The object of the analysis is container cargo of Choyang Line, Hanjin Shipping and Hyundai Merchant Marine of National Frag Carriers. The source materials used in this study are Trucking Data of Hanjin Co., Container Ren-tal Data of Samik Transport Co. and Transpor-ting Present Condition Tables of Hyundai Mer-chant Marine. 1. There are two kinds of the transport classi-fied by its form: FCL and LCL. In Pusan Con-tainer Export, a lot of textile goods, clothings and furniture, compound, electric goods, and so on are dealed with but the rate of occupation of the transport is getting lower while that of occupation of equipment, papers and agricultu-ral, mineral and livestock industry higher. 2. In 1990, the transports of container cargo in Korea consist of 7 services and round-the world lines. We can list North America lines, East-South Asian lines, Japan lines and Inter European lines, in order of the quantity of tran-sport form the largest to the smaller. We can have another list that Japan lines, North Ame-rica lines and East-South lines in order of the rate participation of national flag carriers, be-cacuse Korean foreign trade lay disproportionate emphasis on East-South Asian lines. Japan lines among them is the biggest import-export market. Since the rationlization policy of marine tran-sport in 1984, each of national flag carriers have its own lines. Hanjin Shipping predominates over North America lines, Choyang Line over New Zealand, Inter European and Austria lines and Hyundai Merchant Marine over Center-South America lines, in terms of the volume of transport. And small-to-medium sized shippers are prevailing in lines which are adjacent to Korea, Such as Japan lines and East-South Asian lines. 3. In relation to hinterlands and forelands of Choyang Line, the light industry goods, electric goods and machinary produced in Seoul and Pusan are exported to the major ports in Europe and Japan, the same produces in Suwon, Ulsan, Kumi are exported to European Ports, and those in Incheon and Kwangju Austrian and Japanese ports, and those in the rest regions to the major port in Japan. 4. In relation to hinterlands and forelands of Hanjin Shipping, the light industry goods pro-ducing in Seoul and Pusan, the electric goods and machinary in Incheon and Pyeongteck, are exported to New York and Los Angeles. Electric goods and machinary Masan, Anyang, Cheona, Cheongju and Incheon, Electric goods machinary and light industry goods in Kwangju and non mental goods in Pohang, are exported New York, Los Angeles and Oakland. 5. In relation to hinterlands and forelands of Hyundai Merchant Marine, the region of Seoul, Pusan and Incheon closely related with the main ports in U.S.A. The rest regions with Montreal. The hinterlands of export container cargo can be classified by its export items into three kinds: the large city, industrial city and the rest city. Choyang Line's forelands are European lines, Japan lines and Austria lines, and Hanjin Shipping's forelands are North America lines, and Hyundai Merchant Marine's forelands are North America lines and Japan line. 3 National flag carriers' major forelands are determined by the size of port and the shipper's convenient use of the port terminal.

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