• Title/Summary/Keyword: Distributed resources

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SoQ-based Relay Transmission Protocol for Wireless USB over WiMedia D-MAC (WiMedia D-MAC 기반 Wireless USB 시스템을 위한 SoQ-based 릴레이 통신 프로토콜)

  • Hur, Kyeong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.6
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    • pp.1324-1329
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    • 2013
  • The WiMedia Alliance has specified a Distributed Medium Access Control (D-MAC) protocol based on UWB for high speed wireless home networks and WPANs. In this paper, firstly, the fair SoQ-based Distributed Reservation Protocol (DRP) for D-MAC is analyzed. And a novel SoQ-based relay transmission protocol is proposed to overcome DRP conflicts fast. In the proposed protocol, each device executes the Satisfaction of QoS (SoQ) time slot allocation algorithm independently. And, in order to give the loser device due to DRP conflicts another chance to maintain QoS resources, the proposed relay transmission protocol helps the device reserve another indirect link maintaining the required QoS resources via a relay node.

Relay Communication Scheme for Conflict Avoidance in Wireless USB System (무선 USB 통신 시스템에서 충돌 회피를 위한 릴레이 통신 기법)

  • Kim, Jin-Woo;Kim, Kyung-Ho;Lee, Seong Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.8
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    • pp.696-707
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    • 2014
  • In this paper, firstly, performance degradation due to the Private Distributed Reservation Protocol (DRP) conflict problem caused by devices' mobility is analyzed. And a novel relay transmission protocol combined with Private DRP conflict resolution is proposed to overcome the performance degradation at Private DRP conflicts. In order to give the loser device due to Private DRP conflicts another chance to maintain resources, the proposed relay transmission protocol executed at each device helps the loser device reserve another indirect link maintaining the required resources via a relay node.

In situ side-aspect target strength of Japanese anchovy (Engraulis japonicus) in northwestern Pacific Ocean (북서 태평양 멸치(Japanese anchovy)에 대한 측면 음향 반사강도 특성)

  • Lee, Hyung-Been;Kang, Don-Hyug
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.3
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    • pp.248-256
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    • 2010
  • Acoustic side-aspect target strength (TS) of living Japanese anchovy (Engraulis japonicus) was measured at 120kHz during in situ experiments. The data were collected by lowering and horizontally projecting the splitbeam transducer into the anchovy school. For analysis and interpretation of the side-aspect TS data, acoustic theoretical model, based on the fish morphology, and dorsal-aspect TS data were used. Total length of the anchovy ranged from 6.6 to 12.8cm (mean length 9.3cm). The side-aspect TS distributed between -40 and -55dB, has an obvious length dependency. The mean side-aspect TS of the anchovy was -47.8dB, and the TS was about 2dB higher than mean TS generated from dorsal-aspect measurements. With reference to maximum TS, the results of the side-aspect TS were distributed within the range of the theoretical and dorsal-aspect TS. Apparently these tendency indicates that side-aspect TS measured from the study is useful data. These in situ measurements of side-aspect TS can be applied to improve acoustic detection and estimates of the anchovy, and is necessary to measure with a various frequency and length for making enhance data.

Investigation of Useful Substances for Plants Distributed in Southern Region of Korea I. Saponins and Alkaloids (남부지방 서식식물의 유용물질 탐색 II. Saponins과 Alkaloids)

  • 현규환;임준택;김학진
    • Korean Journal of Plant Resources
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    • v.10 no.4
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    • pp.334-345
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    • 1997
  • This research was conducted to determine contents of saponins and alkloids for plants distributed in the sourthern region of Korea. The extracts from each plants were purified by solvent fractionation, column chromatography, TLC and analyzed GC and HPLC. As a result, contents crude gingseng saponins and saikosaponins were the highest in Oenothera odorata and Metaplexis japonica, respectively. and contents crude alkaloids was the highest in Metaplexis japonica among the all plants xamined. HPLC was conducted to detect of saponins. As a result, ginseng saponin-like substances was detected in the extracts of Euphobia splendens, Taraxacum mongolicum and Metaplexis japonica, gingsen-like substances and its of saikosaponin c-like substances was detected in the extracts of Camellia japonica and Aleurites fordii. GC was conducted to detect of alkaloid. As a result, nicotine-like substances was detected in only the extracts of Fatsia japonica.

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Investigation of Useful Substances for Plants Distributed in Southern Region of Korea I. Lipids and Hydrocarbons (남부지방 서식식물의 유용물질 탐색 I. 지질 및 탄화수소)

  • 현규환
    • Korean Journal of Plant Resources
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    • v.10 no.4
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    • pp.324-333
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    • 1997
  • This research was conducted to determine contents of lipids and hydrocarbons for plants distributed in the sourthern region of Korea. The lipid extracts from each plants were purified by solvent fractionation, column chromatography. TLC and analyzed by gas chromatography. As a result, contents netural lipids and phospholipids were the highest in Aleurites fordii and Camellia japonica among the all plants examined. Most of the fatty acids in lipids was palmitic acid, oleic acid and linoleic acid. Content of hydrocarbon was the highest in Fatsia japonica among the all plants examined. Hydrocarbons contained in the plant was mainly more than 16 number of carbons.

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Genome Scale Protein Secondary Structure Prediction Using a Data Distribution on a Grid Computing

  • Cho, Min-Kyu;Lee, Soojin;Jung, Jin-Won;Kim, Jai-Hoon;Lee, Weontae
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.65-65
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    • 2003
  • After many genome projects, algorithms and software to process explosively growing biological information have been developed. To process huge amount of biological information, high performance computing equipments are essential. If we use the remote resources such as computing power, storages etc., through a Grid to share the resources in the Internet environment, we will be able to obtain great efficiency to process data at a low cost. Here we present the performance improvement of the protein secondary structure prediction (PSIPred) by using the Grid platform, distributing protein sequence data on the Grid where each computer node analyzes its own part of protein sequence data to speed up the structure prediction. On the Grid, genome scale secondary structure prediction for Mycoplasma genitalium, Escherichia coli, Helicobacter pylori, Saccharomyces cerevisiae and Caenorhabditis slogans were performed and analyzed by a statistical way to show the protein structural deviation and comparison between the genomes. Experimental results show that the Grid is a viable platform to speed up the protein structure prediction and from the predicted structures.

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Flood Forecasting by using Distributed Models with Ensemble Kalman Filter (앙상블 칼만필터 이론을 이용한 분포형모델의 홍수유출예측)

  • Park, Hyo-Gil;Choi, Hyun-Il;Jee, Hong-Kee
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.27-31
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    • 2009
  • 홍수피해를 예방할 수 있는 대책에는 여러 가지 방법이 있으나 비구조물적인 방법 중에서 대표적인 것이 홍수예경보이다. 이에 합리적인 설계홍수량 산정을 위해 하천유역에서 강우-유출과정의 정확한 해석과 유출예측은 수자원의 효율적인 활용과 하천의 이수, 치수를 위한 수문학적 해석에 있어서 매우 중요하며, 이를 위해서는 강우로부터 정도 높은 유출량 예측이 요구된다. 뿐만 아니라 하천범람 등의 재해로부터 인명과 재산을 보호하기 위한 홍수예경보 시스템의 구축이 필요하다. 홍수예경보 시스템의 효율적인 관리를 위해서는 실시간 홍수예측(Real-time Flood Prediction)기법의 개발이 필요하다. 홍수유출모형에 있어 공간적 변화특성과 평균 강우량의 공간분포를 반영할 수 있는 분포형 매개변수 모형(Distributed-Parameter Model)인 분포형 모델을 대상으로 앙상블 칼만필터(Ensemble Kalman Filter, EnKF) 이론을 적용하여 비선형시스템에서 오차를 포함한 반응을 실시간으로 처리하여 불확실성을 정량적으로 감소시켜 홍수유출을 예측하는데 그 목적이 있다. 하천유역특성을 이용한 홍수유출예측을 위하여 비선형시스템에서의 앙상블 칼만필터 기법을 적용한 분포형 모형을 이용하여 더욱 정밀한 홍수유출을 예측하게 되고 향후 홍수예경보모형으로서 적정 유역분할 규모를 결정해주는 근거를 제시할 수 있을 것으로 기대된다.

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A Proposal of Institutional Prerequisites to the Participation of Virtual Power Plant in Electricity Market under the Smart Grid Paradigm (스마트그리드 하에서 가상발전소의 전력시장 참여를 위한 제도적 선결요건에 관한 제언)

  • Chung, Koo-Hyung;Park, Man-Geun;Hur, Don
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.3
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    • pp.375-383
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    • 2015
  • The virtual power plant (VPP) is a new technology to achieve flexibility as well as controllability, like traditional centralized power plants, by integrating and operating different types of distributed energy resources (DER) with the information communication technology (ICT). Though small-sized DERs may not be controlled in a centralized manner, these are more likely to be utilized as power plants for centralized dispatch and participate in the energy trade given that these are integrated into a unified generation profile and certain technical properties such as dispatch schedules, ramp rates, voltage control, and reserves are explicitly implemented. Unfortunately, the VPP has been in a conceptual stage thus far and its common definition has not yet been established. Such a lack of obvious guidelines for VPP may lead to a further challenge of coming up with the business model and reinforcing the investment and technical support for VPP. In this context, this paper would aim to identify the definition of VPP as a critical factor in smart grid and, at the same time, discuss the details required for VPP to actively take part in the electricity market under the smart grid paradigm.

Efficient Interference Control Technology for Vehicular Moving Networks

  • Oh, Sung-Min;Lee, Changhee;Lee, Jeong-Hwan;Park, Ae-Soon;Shin, Jae Sheung
    • ETRI Journal
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    • v.37 no.5
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    • pp.867-876
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    • 2015
  • This paper proposes an efficient interference control scheme for vehicular moving networks. The features of the proposed scheme are as follows: radio resources are separated into two resource groups to avoid interference between the cellular and vehicle-to-vehicle (V2V) links; V2V links are able to share the same radio resources for an improvement in the resource efficiency; and vehicles can adaptively adjust their transmission power according to the interference among the V2V links (based on the distributed power control (DPC) scheme derived using the network utility maximization method). The DPC scheme, which is the main feature of the proposed scheme, can improve both the reliability and data rate of a V2V link. Simulation results show that the DPC scheme improves the average signal-to-interference-plus-noise ratio of V2V links by more than 4 dB, and the sum data rate of the V2V links by 15% and 137% compared with conventional schemes.

A short record for the distribution of 4 rare plants (희귀식물 4종의 신분포지 보고)

  • Son, Hyun-Deok;Kim, Dong-Hyeon;Im, Hyoung-Tak
    • Korean Journal of Plant Taxonomy
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    • v.38 no.4
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    • pp.565-571
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    • 2008
  • In the course of execution for Inventories and Management of Plant Resources of Korea, We found new habitats of 4 plant species which distribution ranges are obscure and/or extremely restricted. A subtropical fern distributed in Jeju-do, Woodwardia japonica (L. f.) Sm., was found in Mt. Gambang-san of Hampyeong-gun, Jeollanam-do. A saprophytic orchid, Galeola septentrionalis Reichb., was found in Mt. Ggachi-bong of Boseong-gun, Jeollanam-do. Peristrophe japonica (Thunb.) Bremek., known in Jeollanam-do, was newly found in Mt. Mudeung-san of Gwangju-si. Viburnum furcatum Blume mainly distributed in Jeju-do and Ulleung-do was found in Mt. Jabyeong-san of Gangneung-si, Gangwon-do.