• Title/Summary/Keyword: 전환구간

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Flood Stage Analysis and Prediction of River Bed Change for Stream Corridor Restoration Model with River Vegetation (하천식생 복원모형의 홍수위 분석과 하상변동 예측)

  • Song, Joong-Geun;Kim, Byeong-Chan;Lee, Jong-Seok
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.437-441
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    • 2009
  • The modern times is as special as from the river, the river is very important of our life. The importance to preserve the river environment has been issued and the river developing method is being changed to use potential function of nature as well as flood control. Essential element of the river restoration is a vegetation. The flow resistance by vegetation along the river banks is greatly increase the flood stage. Therefore, the flow resistance due to vegetation in the river and roughness coefficient changes to understand the hydraulic characteristics is an important elements in the river restoration. The purpose of this study is to analyze the flood stage and the aspects of riverbed changes due to the corridor restoration with river vegetation. In order to simulate the flood stage and riverbed changes, HEC-RAS, RMA-2, and SED-2D model were applied for the upstream and downstream in study reaches, respectively.

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Analysis on Interference Impact of WiFi on DTV (DTV에 대한 WiFi의 간섭영향 분석)

  • Cheng, Yan-Ming;Cho, In-Kyoung;Lee, Il-Kyoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.11B
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    • pp.1357-1362
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    • 2011
  • TV White Spaces (TVWS) are freed up after transition from analog television to Digital Television (DTV). Some wireless communications are allowable to operate in TVWSs, such unlicensed Wireless Fidelity (WiFi). Because TVWSs are located in the VHF and UHF bands, TVWSs can provide significantly better coverage and wall penetration inside buildings and other structures than the 2.4 GHz and 5 GHz WiFi frequencies currently in use. Therefore, this paper assumes that WiFi will be deployed in TVWSs. However, the interference impact of WiFi on DTV has to be taken into account. The interference probability in DTV receiver was evaluated by using Spectrum Engineering Advanced Monte-Carlo Analysis Tool (SEAMCAT). As a result, when 20 WiFi UEs are simultaneously operating at the maximum transmit power of 23 dBm and the guard band is 22 MHz, the protection distance should be at least 6 km to meet the interference probability of 5% in DTV receiver.

LTE Femtocell Network Configuration and an Off-Load Scheme According to Traffic Type within Smart Shipyard Area (스마트 조선소내 LTE 펨토셀 네트워크 구성과 트래픽 종류에 따른 오프로드 방식)

  • Kim, Su-Hyun;Jung, Min-A;Lee, Seong Ro;Min, Sang-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.8
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    • pp.667-673
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    • 2014
  • In a smart shipyard area, it is possible to integrate a variety of ship modules from separate sites into a final ship construction by using mobile applications. In this paper, we proposed the LTE femtocell network configuration which is applicable to sub shipyard, the traffic exchange method with shipyard headquarter and offload method to separate the general traffic. We defined the mode change in a femtocell gateway for supporting offload for general traffic between the main server in shipyard headquarter and sub shipyard, the offload data managements and message definition. We check the transmitted/received message flow in the wireless link, and consider the performance of the proposed method using state the transition diagram. It is expected that our results can improve the productivity within a smart shipyard by mobile communications and LTE femtocell network.

Cloning and protein expression of Actinobacillus actinomycetemcomitans cytolethal distending toxin subunit CdtA (Actinobacillus actinomycetemcomitans의 cytolethal distending toxin subunit CdtA 유전자 클로닝과 단백질 발현)

  • Ko, Sun-Young;Jeong, Dong-Keun;Ryu, So-Hyun;Kim, Hyung-Seop
    • Journal of Periodontal and Implant Science
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    • v.37 no.sup2
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    • pp.339-351
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    • 2007
  • Cytolethal distending toxin(CDT)은 세포 주기 중 G2에서 M 기로의 전환을 막아 세포의 증식을 억제할 수 있는 세균 단백 독소의 일종이다. 구강 미생물 중 유일하게 Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans)만이 이 CDT를 생성 할 수 있는 것으로 알려져 있다. A. actinomycetemcomitans는 localized aggressive periodontitis (LAP)의 원인균으로 여겨지며 비 운동성의 그람 음성 구간균이고 $37^{\circ}C$, 5% $CO_2$ 하에 성장이 왕성하다. A. actinomycetemcomitans의 CDT는 3개의 인접한 유전자인 cdtA, cdtB, cdtC에 의해 형성 되며 각각의 유전자에 대한 단백질의 기능은 아직 완전히 밝혀지지 않았다. 현재까지 연구에 의하면 cdtA는 CDT의 세포부착과 관련이 있는 것으로 여겨지며 이 유전자의 기능 이상 시 CDT의 독성 효과가 현저히 감소한다고 알려져 있다. 따라서 본 연구는 A. actinomycetemcomitans의 cdtA 유전자를 클로닝, 단백질 발현하여 향후 치주질환의 발병 과정에서 CdtA의 역할을 규명하고 질환의 예방 및 치료법에 도움을 주고자 하였다. A. actinomycetemcomitans Y4균주를 cdtA 유전자 클로닝을 위해 사용하였다. A. actinomycetemcomitans의 genomic DNA는 genomic DNA 추출 kit를 사용하여 분리하고 cdtA에 특이적인 primer를 이용하여 PCR을 통해 cdtA 유전자를 증폭하였다. 증폭된 cdtA 유전자를 T-vector에 클로닝 하였으며, 클로닝 된 cdtA 유전자는 단백질 발현을 위해 pRSET Avector에 서브클로닝 한 후 발현 균주인 BL21(DE3)를 이용하여 발현시켰다. 발현 후 Ni-NTA AP conjugate를 이용한 Western blot을 통해 pRSET-CDTA를 확인하였다.

A Jet Strobe Signal Timing Control of Ink Jet Printer Head for Enhancement of Printing Speed and Quality (인쇄 속도 향상과 화질 개선을 위한 잉크젯 프린터 헤드의 액적 분사 신호 타이밍 제어)

  • Cho, Young-Wan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.8
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    • pp.1727-1734
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    • 2011
  • In this paper, a position control scheme of the ink droplet is presented for the high image quality and print speed ink jet printer. The proposed scheme estimates the impact position and compensates it by control of the jet strobe time based on the dynamic equations describing the moving trajectory of the ejected ink droplet. Compared to the conventional jet strobe control which is based on the simple synchronization with the position signal of the ink jet nozzle, the proposed control scheme provides more accurate impact position control while the carrier is moving with accelerated or decelerated speed as well as steady state speed with fluctuations. The availability of printing during the acceleration and deceleration states of the carrier moving enables the print speed up and the frame size down which means the cost down.

DF(Dynamic and Flexible)-MAC : A Flexible MAC Protocol for WBAN (DF(Dynamic and Flexible)-MAC : WBAN을 위한 유연한 MAC 프로토콜)

  • Seo, Young-Sun;Kim, Dae-Young;Kim, Beom-Seok;Cho, Jin-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.8A
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    • pp.712-722
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    • 2011
  • Wireless body area network(WBAN) provide communication service in the vicinity of the body. Since WBANs utilize both MICS frequency band for implant medical applications and ISM frequency band for medical and consumer electronics(CE) applications. Therefore, MAC protocols in WBAN should be designed considering flexibility between medical and CE applications. In this paper, we identify the requirements of WBAN MAC protocols and propose a WBAN MAC protocol which satisfies the requirements. In other to provide transmission flexibility for various applications. we present the dynamic CFP allocation and opportunity period. Extensive simulation result show that the proposed protocol achieves improved throughput and latency in WEAN environment cimpared with IEEE 802.15.4.

A Study on Constructing Bottom-up Model for Electric Sector (전력부문 온실가스 감축정책 평가를 위한 상향식 모형화 방안)

  • Kim, Hugon;Paik, Chunhyun;Chung, Yongjoo;Ahn, Younghwan
    • Journal of Energy Engineering
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    • v.25 no.3
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    • pp.114-129
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    • 2016
  • Since the release of mid-term domestic GHG goals until 2020, in 2009, some various GHG reduction policies have been proposed to reduce the emission rate about 30% compared to BAU scenario. There are two types of modeling approaches for identifying options required to meet greenhouse gas (GHG) abatement targets and assessing their economic impacts: top-down and bottom-up models. Examples of the bottom-up optimization models include MARKAL, MESSAGE, LEAP, and AIM, all of which are developed based on linear programming (LP) with a few differences in user interface and database utilization. The bottom-up model for electric sector requires demand management, regeneration energy mix, fuel conversation, etc., thus it has a very complex aspect to estimate some various policies. In this paper, we suggest a bottom-up BAU model for electric sector and how we can build it through step-by-step procedures such that includes load region, hydro-dam and pumping storage.

A Study on the Reaction Characteristics of the NH3 Oxidation over W/TiO2 (W/TiO2 촉매의 NH3 단독 산화 반응 특성 연구)

  • Kim, Geo Jong;Lee, Sang Moon;Hong, Sung Chang
    • Applied Chemistry for Engineering
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    • v.24 no.6
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    • pp.645-649
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    • 2013
  • In this study, we investigated the $NH_3$ oxidation reaction characteristic over $W/TiO_2$ catalyst in order to control $NH_3$ generated from a thermoelectric power plant or incinerator. As a result, it was found that the optimal content of tungsten in $W/TiO_2$ catalyst is 10 wt% and $NH_3$ removal efficiency decreased due to decreasing specific surface areas of catalyst with increasing tungsten contents. When $NH_3$ was injected more than 420 ppm, $NH_3$ conversion decreased at the middle temperature range. In addition, $NH_3$ conversion decreased due to the competitive adsorption of moisture and with increasing oxygen concentration, the $NH_3$ conversion increased while the $N_2$ selectivity decreased.

Analysis of Transportation Mode Choice Behavior Based on Accessibility : Focused on Chungnam-Weihai route (접근성에 따른 운송수단 선택행동에 관한 분석 : 충남-위해구간을 중심으로)

  • Choi, Jung-kyu
    • Journal of Korea Port Economic Association
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    • v.32 no.4
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    • pp.183-192
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    • 2016
  • The purpose of this study is to analyze the choice behavior of the mode of transportation for travel from Korea to China. Discrete choice analysis is utilized to establish the factors that affect travelers' choice and to quantify the importance of these factors in transportation mode choices. The proposed choice models were constructed by using stated-preference (SP) data obtained from Chungcheongnam-do. This study also examined different choice behavior in order to capture any previously unobserved differences in the residence area. Results showed that the access time and frequency attributes are the most significant factors, while the travel time attributes are the least significant factors for travelers' choice behaviour. The insights of the results described in this research provide some practical suggestions to transportation providers for planning and strategic management endeavors in the future.

부지화 감귤의 저장 품질특성에 미치는 중온처리 효과

  • 이현희;홍석인;손석민;김동만
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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    • pp.188.2-189
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    • 2003
  • 시설재배 만감류인 부지화 감귤의 수확후 저장유통시 부패 감소 및 상품성 제고를 위하여 환경친화적 전처리방법으로서 중온처리의 적용 가능성을 확인하고자, 제주 서귀포산 부지화(한라봉)감귤의 열수 및 열풍 처리에 따른 저장중 품질특성 변화를 살펴보았다. 표면상처가 없는 일정 크기의 건전 과실을 선별한 후, 각각 52$^{\circ}C$에서 2분(52-2m), 6$0^{\circ}C$에서 20초(60-20s) 동안 열수에 침지하거나 45$^{\circ}C$에서 4시간(45-4h), 8시간(45-8h) 동안 열풍을 가한 다음 5$^{\circ}C$에서 냉각 건조하였다. 충분히 냉각된 과실을 통기성 천공 LDPE 필름에 포장하여 5"C에서 21일, 18$^{\circ}C$에서 7일간 저장하면서 생리, 이화학, 관능적 특성을 측정하였다. 중온처리 직후 초기 호흡률은 처리구 모두 무처리구와 비교하여 다소 높았으나, 저장중 처리구 감귤의 호흡률은 감소하여 21일째는 무처리구와 동일한 수준을 나타내었다. 과실내 기체조성은 저장기간 및 처리구간에 차이를 보이지 않았으나 21일부터는 저장온도 전환에 따라 $CO_2$가 다소 증가하는 양상을 보였다. 과실의 pH, 산도, 경도는 중온처리에 따른 유의적 차이를 구분할 수 없었으나, 고형분 함량과 생체 중량감소율은 열풍처리구에서 다소 높게 유지되었다. 과피 표면색 역시 열풍처리구 (45-8h)가 다른 것에 비해 저장중 짙게 나타났으나 열수처리구에서는 가시적 변화를 발견할 수 없었다. 한편 부패과 발생률에 있어서 열수처리구가 축부병 등에 의한 짓무름 현상 및 곰팡이 발생정도를 가장 낮게 나타내었고, 관능검사에서도 열수처리구가 변색, 시듦, 광택 등의 외관 품질항목에서 유의적으로 우수하게 평가되었다. 결과적으로 중온 열수처리는 부지화 김귤의 수확후 저장유통중 부패과 발생률을 감소시키고 외관품질을 유지하는데 효과적인 전처리방법임을 확인할 수 있었다. 있었다.

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