• Title/Summary/Keyword: 계단보

Search Result 144, Processing Time 0.027 seconds

An Assessment of Ascending Functions of the Pool-and-Weir Fishway at Jamsil Weir in the Han River (한강 잠실수중보 계단식 어도의 어류소상기능 평가)

  • Park, Sang-Deog;Shin, Sung-Sook;Ahn, Hyo-Yoon;Ma, Soo-Bong;Hwang, Chong-Seo
    • Journal of Korea Water Resources Association
    • /
    • v.37 no.7
    • /
    • pp.541-552
    • /
    • 2004
  • In this paper, ascending functions of the pool-and-weir fishway which has been established for the upstream migration of migratory fish at Jamsil Weir in the lower part of the Han River was assessed by applying tile Existing Fishway Measurement Method, and measures to improve these functions were suggested. The primary fish which ascended the fishway during the period of measurement was Erythroculter erythropterus Basilewsky, greater than 29cm in the body length. A total of 361 individual fish were collected with traps established at the exit of the fishway The maximum ascending capacity for the fish was 2.53${\times}$10^{-3}$ fish/hr/g. The fishway of Jamsil Weir does not satisfy the various fish species inhabiting in the river. Especially, small fishes of lower swimming ability may not ascend the fishway because the difference in water levels between upper and lower pools in the fishway was too large at the exit and there was too much discharge flowing into the fishway. This fishway does not have a roll in the ascending function for other species except Erythroculter erythropterus Basilewsky and Hemibarbus labeo Pallas, for which swimming ability is great. In order to improve the ascending function of the fishway, the structures of the fishway need to be changed so that various species in the river can easily ascend and the fishway function be taken into consideration in operation of the gates of the weir. Additional construction of fishways on both sides of the lower flow channel are needed to correct a decline in the fishway effectiveness due to continuous flow over the fixed part of the weir.

A Simple Transcoding Method for H.264 Coding System (H.264 부호화시스템에서 간단한 비트열 변환 기법)

  • Yang, Young-Hyun;Kwon, Soon-Kak
    • Journal of Korea Multimedia Society
    • /
    • v.9 no.7
    • /
    • pp.818-826
    • /
    • 2006
  • In this paper, we investigate the relationship of bitrate and quantization parameter needed for the trans-coding method that makes the H.264 bitstream of a particular bitrate to the other titrate. Also we propose the new method in order to transcode the titrate between H.264 video coded bitstreams. The proposed transcoding method updates the model parameters from previous picture or slice by using the approximated relationship of bitrate and quantization step-size and finds the target quantization step-size, and then generates the target titrate by simple coding processing just after requantization. Therefore, the proposed method does not need the complex bitrate control and converts to the target titrate by simple implementation. From simulation, we can see that the proposed method transcodes exactly to an assigned target bitrate for the four test sequences with different their characteristics.

  • PDF

STM(Scanning Tunneling Microscope)의 제작 시 고려사항과 응용사례

  • 구자용
    • Proceedings of the Korea Crystallographic Association Conference
    • /
    • 2002.11a
    • /
    • pp.7-7
    • /
    • 2002
  • 실공간 (real space)에서 원자분해능을 보여주는 STM의 작동원리를 핵심사항을 중심으로 설명하며 또한 실제 제작 시 고려해야 하는 사항들을 구체적으로 검토한다. 반도체의 경우 전자들이 원자부근에서 국소화가 잘 되므로 STM으로 표면의 원자상을 얻기가 비교적 쉽다. 특히 실리콘은 그 물질의 중요성과 결부되어 STM으로 많이 연구되어 왔으며 다른 방법으로는 알 수 없는 독특한 결과들을 보여주었다. STM의 응용사례로써 오랫동안 수수께끼였던 Si(001) 표면에서 생기는 점결함(point defect)과 계단 (step)부근의 원자구조 및 최근의 몇 가지 연구결과에 대한 기본적인 결과들을 소개한다.

  • PDF

Surface Microtopography of Pyrophyllite Crystals from Gussi Deposit, Korea (전남 구시광산에서 산출하는 엽납석 결정의 표면 미세형태)

  • Mayumi Jige;Ryuji Kitagawa;Hwang, Jin-Yeon
    • Journal of the Mineralogical Society of Korea
    • /
    • v.17 no.2
    • /
    • pp.115-121
    • /
    • 2004
  • The surface microtopography of pyrophyllite collected from the Gussi deposit, Korea was observed by mean of transmission electron microscopy (TEM) with the gold decoration technique. As results, closed step patterns with malformed circular islands were characteristically observed on the (001) surface of pyrophyllite, contrasting with spiral step patterns common in illite and kaolinite. Gussi pyrophyllite was likely crystallized from hydrothermal solution of higher temperature and/or higher supersaturation than those of other clay minerals. Comparing with micro-topographies of pyrophyllite from the Shokozan and the Uku deposits, southwest Japan, growth mechanism of Gussi pyrophyllite is almost equivalent to those from the Shokozan and the Uku deposits.

A Hybrid Boundary Integral Equation Model Applied for the Calculation of Normal Incident Waves (혼합경계적분 요소법을 사용한 직교입사파랑의 반사률계산 모델)

  • 서승남;김상익
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.3 no.3
    • /
    • pp.170-175
    • /
    • 1991
  • In order to calculate reflection coefficients of surface waves due to underwater obstacles, the hybrid boundary integral equation method is used. Numerical results based on the linear element are verified to the exact solutions for a flat bottom. Reflection coefficient and transmission coefficients for a step are compared to Young's results and the results by EFEM (Kirby et al., 1987), in which reflection coefficients decrease to zero as the periods of incident waves decrease. Reflection coefficients for a sinusiodal hump located on a constant depth increase due to the interaction between humps.

  • PDF

Deinterlacing Using Multi-Directional Edge Information (다각도의 에지 정보를 이용한 디인터레이싱)

  • Lee, Dong-Wook;Kang, Mun-Bong
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.11 no.2
    • /
    • pp.92-96
    • /
    • 2010
  • Deinterlacing methods are usually divided into inter-field deinterlacing and intra-field deinterlacing. The most common method of intra-field deinterlacing is the linear method which uses line doubling or line averaging. There are also some edge-enhancement methods such as ELA(Edge Based Line Average) and modified ELA. However, the linear interpolation generates edge blurring or staircase artifacts. The methods using ELA or modified ELA show poor deinterlacing at various types of edges because of insufficient edge information in a certain direction. This paper presents an intra-field deinterlacing algorithm that considers the interpolation based on edges in 7 directions and an edge line in the horizontal direction. It demonstrates better picture quality by reducing the staircase phenomenon of object in the conventional methods.

Dynamic Simulation for Waste-Oil Gasification Process (폐유가스화 공정의 동적모사)

  • 고은용;이승종;윤용승
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
    • /
    • 2001.11a
    • /
    • pp.57-62
    • /
    • 2001
  • 본 연구에서는 검증된 BSU 3톤/일급 석탄가스화공정에 대해 개발된 동적모델을 폐유가스화 공정모텔에 적용하였다. 대상공정에 포함된 조작변수들의 변동에 따른 주요 공정변수인 산소/폐유비를 3% 계단증가시킨 결과, 폐유가스화기의 압력은 15분의 시상수를 보이며 최종적으로 2.4%가 증가된 정상상태에 도달하였고, 온도는 초기 1분 이내에 약 3.2%의 급격한 증가를 보인 후 최종적으로 4.1% 증가된 정상상태에 도달하였다. 그리고 생성가스의 조성은 이산화탄소가 6% 증가되었고, 일산화탄소와 수소는 각각 2% 및 8% 감소된 새로운 정상상태에 도달하였다. 이러한 결과를 토대로 폐유가스화기의 부하변동에 따른 주요 공정변수들의 변동경향 및 신뢰성 있는 동적모사 결과를 얻고, 개발된 모델에 cascade 및 ratio 방식의온도, 압력 제어로직을 설계하여 실공정 적용실험을 통한 전산모사결과 및 안정된 운전특성을 검증할 수 있는 기초를 마련하였다.

  • PDF

Prediction of Dynamic Characteristics of Continuous Systems Due to the Mass Modification (질량변경에 따른 연속계의 동특성변화 예측)

  • 이정윤;최상렬;박천권;오재응;정석주
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.17 no.2
    • /
    • pp.248-256
    • /
    • 1993
  • This paper deriver the generalized mass to find dynamic characteristics and its derivatives of a continous system. And a new sensitivity analysis method is presented by using the amount of change of generalized mass and vibrational mode caused by the variation of lumped and distributed mass. In this paper, to get or detect appropriate results, cantilever beam and stepped beam are used. Deviations of sensitivity coefficient, natual frequency, vibrational mode and transfer function are calculated as result, and compared with the theoretical exact values.

가정 내 안전사고 예방

  • KOREA ASSOCIATION OF HEALTH PROMOTION
    • 건강소식
    • /
    • v.31 no.5 s.342
    • /
    • pp.32-33
    • /
    • 2007
  • 최근 한국소비자보호원에서 발표한 2006년도 소비자 위해 정보 통계분석 결과에 따르면, 위해 발생 장소별로 볼 때 가정에서의 안전사고가 가장 많은 발생 빈도를 보이고 있다. 최근 3년간 위해발생 접수 건수 중 가정 내발생 비율 역시 2004년 3,069건(35.2%), 2005년 4,392건(36.1%), 2006년 7,348건(49.5%)로 계속 증가 추세를 나타내고 있다. 가정 내 위해의 발생 원인은 식료품 및 기호품, 토지 건물 및 설비, 특히 현관, 계단, 복도, 욕실 등에서의 추락이나 미끄러짐, 충돌 등의 사고가 대부분인 것으로 조사되었다. 연령별로는 10세 미만의 어린이(64.3%)와60세 이상의 노인(58.4%)들에서 가정 내의 사고가 다른 장소에 비해 높은 비중을 차지하고 있었다. 가장 안전한 장소로 여겨지는 가정에서의 이와 같은 경향은 대부분 기본적인 안전 점검에 주의를 기울이지 않거나 안전을 소홀히 생각하기 때문에 발생된다.

  • PDF

Moment Gradient Factor for Lateral Torsional Buckling Strength of Monosymmetric Stepped I-beam Subjected to Uniform Moment

  • Gelera, Kathleen Mae;Park, Jong-Sup
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.10 no.2
    • /
    • pp.7-13
    • /
    • 2010
  • Stepped I-beams having increased moment of inertia at one end (singly stepped beam) or both ends (doubly stepped beams) can often be seen in construction of bridges due to material economy and easy fabrication of the section. This paper presents the results of the parametric study of lateral torsional buckling of monosymmetric stepped I-beams with constant depth subjected to uniform moment. Design recommendations were made based on the finite element results of the models having different combinations of monosymmetric ratio, stepped length ratio, flange thickness ratio and flange width ratio. The proposed approximation is acceptable based on the parameters given having mostly conservative results. The proposed equation can be further used to extend the study to different loading conditions.