• Title/Summary/Keyword: sub-stream

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A Study on the Estimation of Pollutant Runoff using GIS data and Application to the Closed Watershed (GIS 데이터를 이용한 오염 유출량의 해석과 폐쇄성 수역의 적용에 관한 연구)

  • 강상혁;김승호;권재혁;노구정인
    • Spatial Information Research
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    • v.10 no.2
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    • pp.263-273
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    • 2002
  • This paper presents desirable water environmental management to a closed watershed. In order to obtain spatially distributed environmental information, GIS data have been used. Elevation data are used to extract stream channels automatically and to divide networks of a watershed. A Digital Elevation Model (DEM) has been developed, validated, and adopted to estimate the runoff of total nitrogen pollutant from watershed. This GIS-linked model can be applied effectively to the watersheds with many sub-streams, and for the estimation of pollutant runoff considering land use change.

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PIV Analysis of a Pulsating Flow through a Square Channel

  • SAGA Tetsuo;UEDA Toshiyuki;TANIGUCHI Nobuyuki
    • 한국가시화정보학회:학술대회논문집
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    • 2004.12a
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    • pp.157-168
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    • 2004
  • The effects of pulsation in a pulsating flow through a rectangular channel have been investigated by Particle Image Velocimetry in both laminar and turbulent flow conditions. PIV results on a square channel (aspect ratio:1) have been reported on the cases of Reynolds number Re=80 in laminar and Re=8800 in turbulent region. For both in the laminar and turbulent regions, the influence of the pulsation onto the magnitude changes of the average velocity was negligible. In the turbulent region, the magnitude profiles of the stream-wise pulsating component obtained by the theoretical analysis based on the Stokes analogy were slightly different from the experimental ones due to the influence of the turbulent viscosities onto the pulsating flows.

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Design of an EBCOT in JPEG2000 for a Web Camera Server (웹 카메라 서버용 JPEG2000 의 EBCOT 설계에 관한 연구)

  • Park, Ju-Hyun;Kim, Young-Chul;Hong, Sung-Hoon;Lee, Myung-Ok
    • Proceedings of the Korea Information Processing Society Conference
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    • 2001.10a
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    • pp.151-154
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    • 2001
  • 본 연구는 웹 카메라에 적용하기 위한 JPEG2000의 주요 블록인 EBCOT(Embedded Block Coding with Optimized Truncation)의 설계 및 구현에 관한 연구이다. EHCOT 블록은 웨이블렛(wavelet)변환에 의해 분할된 각 sub-band에 존재하는 주위 화소 값들과 상위 bit-plane의 값들에 대한 상호 연관성을 조사하여 context을 추출하고 그 context를 이용하여 엔트로피 부호화(entropy coding)를 수행하는 T1(Tier 1) 블록과 bit-stream을 구성하는 T2(Tier 2) 블록으로 구성된다. 본 논문에서는 JPEG2000에서 전체 압축성능을 좌우하는 EBCOT의 T1 블록을 Synopsys tool을 이용하여 설계하고 구현하였다.

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Extended Web Log Processing System by using Click-Stream (클릭스트림 분석을 통한 확장된 웹 로그 처리 시스템)

  • Kang, Mi-Jung;Cho, Dong-Sub
    • Proceedings of the KIEE Conference
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    • 2001.07d
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    • pp.2798-2800
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    • 2001
  • 인터넷 사용자가 급증하고, 인터넷을 통한 비즈니스에 수익 모델에 대한 관심이 높아지면서 방문자별로 맞춤 정보를 제공하는 퍼스널라이제이션이 인터넷 개발자 및 사용자들의 관심을 모으고 있다. 원투원 마케팅은 개별 고객의 성별, 나이, 소득 등 인구 통계 정보와 고객의 취미, 레저 등에 관한 정보 및 구매 패턴을 DB화하여 고객에게 가장 적절한 상품, 정보, 광고를 제공하는 것이다. 원투원 마케팅을 기본으로 개인과의 끊임없는 상호교류를 통해 고객에게 맞춤 서비스를 제공할수 있다. 본 논문에서는 맞춤 서비스 제공을 위한 전처리과정으로 클릭스트림 분석을 통한 확장된 웹 로그 정보를 통해서 고객들의 성향을 분석하였다. 그리고 이 웹 로그서버는 웹사이트로부터 얻은 로그정보를 분류하고 저장하여 관리자가 확장된 웹 로그 정보를 쉽게 분석할 수 있다. 이때 데이터베이스 저장 기술로 OLE DB Provider상에서 수행되는 ADO 기술을 사용함으로써 확장된 웹 로그 처리 시스템을 설계하였다. 확장된 웹 로그 DB를 패턴분석, 군집분석 등의 마이닝(Mining) 기법을 통하여 맞춤 서비스에 대한 사용자 프로파일을 구축 할 수 있다.

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An Analysis of Shifting Cultivation Areas in Luang Prabang Province, Lao PDR, Using Satellite Imagery and Geographic Information Systems (위성영상과 지리정보시스템을 이용한 라오스 루앙프라방 지역의 화전지역 분석)

  • 조명희
    • Korean Journal of Remote Sensing
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    • v.10 no.1
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    • pp.43-53
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    • 1994
  • By Using MOS-1 satellite image(taken on 24 April 1990, after slash and burn), Shifting cultivation areas were estimated for the sub-basin area. In tropical region to analyse the correlation between shifting cultivation rate and bifurcation rate network which was calculated from topographic map, PC Arc - Info and IDRISI GIS software were used. As the distribution rate of shifting cultivation increases, the bifurcation rate is high. From the correlation analysis between the shifting cultivation and drainage network, it was found that shifting cultivation leads to land degradation and head erosion at the stream valley. To prevent such problems, it is mecessary that shifting cultivation areas should be converted to permanent paddy fields.

Examining the Impact of Co-branding Service Failures on Consumer Evaluations

  • Lee, Chia-Lin
    • Asia Marketing Journal
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    • v.19 no.3
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    • pp.19-44
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    • 2017
  • Researchers do not fully understand consumers' responses to negative co-branding events; thus, they report inconsistent evidence regarding the negative impact on the partnering brands. Our research bridges a gap in this research stream, and answers an important question: When a service failure occurs, could the two different models of consumers' brand schema change affect their negative perception of each brand partner? By using a theoretical and mathematical modeling approach, we offer two propositions. The first proposition shows that, under consumers' book-keeping cognitive process, the negative spillover effect occurs for both brands. The second proposition argues that, when the sub-typing model is assumed, it is possible that one brand suffers while the other escapes the blame for the failure. To our knowledge, this is one of the first few studies to identify circumstances in which a negative spillover effect may or may not occur to brand partners in co-branding service failures.

Development and assessment of water management resilience of mid-small scale tributaries (지류 중소하천의 물관리 탄력성 평가지수 개발 및 평가)

  • Park, Jung Eun;Lee, Eul Rae;Lim, Kwang Suop
    • Journal of Korea Water Resources Association
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    • v.49 no.2
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    • pp.95-106
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    • 2016
  • Water Management Resilience Index (WMRI) was developed as a policy measure of adaptability to withstand water stresses and to set up water management strategies mainly in mid-small scale tributaries, and then evaluated on 117 sub-basins in South Korea. The index consists of 3 sub-indices such as vulnerability, robustness and redundancy sub-indices, each including indicators of 3 sectors: water use, flood mitigation, and river environment. Total number of indicators selected for the index was 31. Taking into account the stream order and control capability of river flow discharge, sub-basins were categorized into 3: 1 for mainstreams of lower large dams, 2 and 3 for tributaries, respectively without and with flow discharge regulation. As a result of the evaluation, resilience index scores in Category 2 and 3 are much lower than that of Category 1, especially with very poor score of redundancy. Although there was no significant difference between mainstream and tributaries in vulnerability and robustness sub-indices, results of redundancy sub-index in tributaries were lower than those in mainstream. Thus, it is conceived that the variety of water management schemes should be considered to improve their resilience in the face of future uncertainty. Addressing comprehensive stability of river basin against internal and external impacts, WMRI in this study can also be used for the prioritization of water management plans.

The application of GIS and RS for extracting Sumjin Watershed hydrologic-parameter (섬진강 유역 수문인자 추출을 위한 GIS와 RS의 활용)

  • 김지은;이근상;조기성;장영률
    • Spatial Information Research
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    • v.8 no.2
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    • pp.257-274
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    • 2000
  • Recently, natural environment is being forced by the quick increasing of population and industrialization, and especially, capacity and pollution of water resource is being come to the front. It needs to extract the accurate topological and hydrological parameters of watershed in order to manage water resource efficiently. But, these data are processed yet by manual work and simple operation in hydrological fields. In this paper, we presented algorithm that could extract topological any hydrological parameters over Sumjin watershed using GIS and RS and it gives the saving of data processing time and the confidency of data. The extraction procedure of topological characteristics and hydrological parameters is as below. First, watershed and stream are extracted by DEM and curve number is extracted throughout the overlay of landcov map and soil map. Also, we extracted surface parameters like watershed length and the slope of watershed length by Grid computation into watershed and stream. And we gave the method that could extract hydrologic parameters like Muskingum K and sub-basin lag time by executing computation into surface parameters and average SCS curve number being extracted.

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Calibration of Parameters in QUAL2E using the Least-squares Method (최소지승법에 의한 QUAL2E 모델 반응계수 보정)

  • Kim, Kyung-Sub;Yoon, Dong-Gu;Lee, Gi-Young
    • Journal of Korea Water Resources Association
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    • v.37 no.9
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    • pp.719-727
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    • 2004
  • Water quality models can be applied to manage the regional water quality problems and to estimate the target and allowable pollution load in watershed effectively. The optimization of state variables in the given water quality model Is necessary to build up more effective model. The least-squares method is applied to fit field observations in QUAL2E developed by U.S. EPA, which is most widely used one in the world to simulate the stream water quality, and the optimization model with constraints is constructed to estimate the parameters. The objective function of the optimization model is solved by Solver in Microsoft Excel and Monte Carlo simulation is conducted to know the influence of parameter in conventional pollutants. It is found that this technique is easily implemented and rapidly convergent computational procedure to calibrate the parameters after appling this approach in Anyang stream located in Kyonggi province mainly.

A Study on the Effect of Mid Layer on Supersonic 2D Double Shear Layer (초음속 2차원 2단 혼합층에서 중간층의 역할)

  • Kim, Dongmin;Baek, Seungwook
    • Journal of the Korean Society of Propulsion Engineers
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    • v.19 no.1
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    • pp.9-17
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    • 2015
  • The basic flow configuration is composed of a plane, double shear layer where relatively thin mid gas layer is sandwiched between air and fuel stream. The present study describes numerical investigations concerning the combustion enhancement according to a variation of mid layer thickness. In this case, the effect of heat release in turbulent mixing layers is important. For the numerical solution, a fully conservative unsteady $2^{nd}$ order time accurate sub-iteration method and $2^{nd}$ order TVD scheme are used with the finite volume method including k-${\omega}$ SST model. The results consists of three categories; single shear layer consists of fuel and air, inert gas sandwiched between fuel and air, cold fuel gas sandwiched between fuel and air. The numerical calculations has been carried out in case of 1, 2, 4 mm of mid layer thickness. The height of total gas stream is 4 cm. The combustion region is broadened in case of inert gas layer of 2, 4 mm thickness and cold fuel layer of 4 mm thickness compared with single shear layer.