• 제목/요약/키워드: Accumulation Estimation

검색결과 173건 처리시간 0.035초

농촌유역의 산림지 면적 감소에 따른 유역 토양유실량 변화 추정 (Estimation of the Forestry Area Decrease Effect on the Soil Erosion in Rural Watershed)

  • 김상민;임상준;박승우
    • 농촌계획
    • /
    • 제10권1호
    • /
    • pp.19-26
    • /
    • 2004
  • In this paper, forestry area change effect on the soil erosion in Asan lake watershed was estimated. Temporal variations of land use in the study watershed were analyzed from Landsat-5 TM remote sensing images. Geographic Information System (GIS) combined with Universal Soil Loss Equation (USLE) was used to estimate the soil erosion of Asan lake watershed. Spatial data for each USLE factors was obtained from the Landsat-5 TM remote sensing images and 1/25,000 scale digital contour maps. Sediment yield to Asan lake was estimated by sediment delivery ratio and sediment accumulation in lake was estimated by trap efficiency. The estimation methods were validated for sediment accumulation in Asan lake. From the hydrographic survey from 1974 to 2003 for Asan lake, sediment accumulation was measured. The estimated accumulation sediment of 303,569ton/yr showed similar value with observed of 295,888ton/yr. From the validated estimation methods, the increasing amount of soil erosion when 1% of forest area in Asan lake watershed decreases was calculated from 12.91 to 1482.05ton/yr.

상관값 누적 기반 DS-UWB 레이더 시스템 (A DS-UWB Radar System Based on Correlation Accumulation)

  • 이영포;윤석호;이성로
    • 한국통신학회논문지
    • /
    • 제38C권4호
    • /
    • pp.359-364
    • /
    • 2013
  • 본 논문에서는 선박 접안 유도 시스템 등 정밀한 거리 추정을 요하는 안전항해운항, 선박트래픽관리 등의 분야에 알맞은 상관값 누적 기반 직접 수열 초광대역 (direct sequence ultra wideband: DS-UWB) 레이더 시스템을 제안한다. 제안하는 DS-UWB 레이더 시스템은 상관기 출력들을 누적하여 잡음을 평균냄으로써 잡음 성분의 영향을 줄이며, 기존의 DS-UWB 레이더 시스템들에 비해 더 빠른 시간에 신뢰성 있는 거리 추정을 수행한다. 모의실험 결과를 통해 제안하는 DS-UWB 레이더 시스템이 기존의 DS-UWB 레이더 시스템들에 비해 평균 상관 처리 시간이 더 짧을 뿐 아니라, 더 좋은 거리 추정 성능을 보임을 확인한다.

항공영상을 이용한 하이브리드 영상 항법 변수 추출 (Hybrid navigation parameter estimation from aerial image sequence)

  • 심동규;정상용;이도형;박래홍;김린철;이상욱
    • 전자공학회논문지S
    • /
    • 제35S권2호
    • /
    • pp.146-156
    • /
    • 1998
  • Thispapr proposes hybrid navigation parameter estimation using sequential aerial images. The proposed navigation parameter estimation system is composed of two parts: relative position estimation and absolute position estimation. the relative position estimation recursively computes the current velocity and absolute position estimation. The relative position estimation recursively computes the current velocity and position of an aircraft by accumulating navigation parameters extracted from two succesive aerial images. Simple accumulation of parameter values decreases reliability of the extracted parameters as an aircraft goes on navigating. therefore absolute position estimation is required to compensate for position error generated in the relative position step. The absolute position estimation algorithm combining image matching and digital elevation model(DEM) matching is presented. Computer simulation with real aerial image sequences shows the efficiency of the proposed hybrial algorithm.

  • PDF

가막만의 COD 거동 및 분포 특성 평가를 위한 생태계 모델링 (Ecological modeling for estimation of a transport and distribution of COD in Kamak Bay)

  • 김동명
    • 한국환경과학회지
    • /
    • 제14권9호
    • /
    • pp.835-842
    • /
    • 2005
  • The three-dimensional eco-hydrodynamic model was applied to estimate the physical process in terms of COD (chemical oxygen demand) and net supply(or decomposition) rate of COD in Kamak Bay to find proper management plan for oxygen demanding organic matters. The estimation results of the physical process in terms of COD showed that transportation of COD is dominant in surface level while accumulation of COD is dominant in bottom level. In the case of surface level, the net supply rate of COD was 0 -0.50 mg/m2/day. The net decomposition rate of COD was 0 -0.04 mg/m2/day in middle level(3 -6m) and 0.05 -0.1 5 mg/m2/day in bottom level(6m -bottom). These results indicates that the biological decomposition and physical accumulation of COD are occurred predominantly at the northern part of bottom level. Therefore, it is important to consider both allochthonous and autochthonous oxygen demanding organic matters in the region.

생태계모델을 이용한 가막만의 영양염 거동 특성 평가 (Estimation of Nutrients Transport in Kamak Bay using the Eco-hydrodynamic Model)

  • 김동명
    • 한국환경과학회지
    • /
    • 제12권7호
    • /
    • pp.745-751
    • /
    • 2003
  • The three-dimensional eco-hydrodynamic model was applied to estimate the physical process in terms of nutrients and net uptake(or regeneration) rate of nutrients in Kamak Bay for scenario analysis to find proper management plan. The estimation results of the physical process in terms of nutrients shelved that transportation of nutrients is dominant in surface level while accumulation of nutrients is dominant in bottom level. In the case of dissolved inorganic nitrogen, the results showed that the net uptake rate was 0∼60 mg/㎡/day in surface level(0∼3m), and the net regeneration rate was 0.0∼10.0 mg/㎡/day in middle level(3∼6m) and above 10mg/㎡/day in bottom level(6m∼below). In the case of dissolved inorganic phosphorus, the net uptake rate was 0.0∼3.0 mg/㎡/day in surface level, and the net regeneration rate was 0.5∼1.5 mg/㎡/day in middle level and 1.0∼3.0 mg/㎡/day in bottom level. These results indicates that net uptake and transport of nutrients are occurred predominantly at the surface level and the net generation and accumulation are dominant at bottom level. Therefore, it is important to consider the re-supplement of nutrients due to regeneration of bottom water.

정보통신기술의 확산과 결정요인

  • 서환주;안정화
    • 기술혁신연구
    • /
    • 제9권2호
    • /
    • pp.56-76
    • /
    • 2001
  • The main purpose of this study is to analyse the digital divide and th determinants of ICT diffusion rate in Korean industries. We estimate the ICT diffusion function using the pooling data for this analysis. The results are as follows. First, the ICT capital accumulated in machinery & equipment, electrical machinery and construction industry is estimated to be 83% of total In capital stock in the 90s. Second, using the panel analysis, we find positive correlation among ICT diffusion, network effect and accumulation of human capital, which is more prominent in the service sector. Third, the estimation results show that the additional 1% increase of human capital accumulation will allow to increase the 0.69% of ICT capital intensity in Korean industries.

  • PDF

RLS Adaptive IIR Filters Based on Equation Error Methods Considering Additive Noises

  • Muneyasu, Mitsuji;Kamikawa, Hidefumi;Hinamoto, Takao
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2000년도 ITC-CSCC -1
    • /
    • pp.215-218
    • /
    • 2000
  • In this paper, a new algorithm for adaptive IIR filters based on equation error methods using the RLS algorithm is proposed. In the proposed algorithm, the concept of feedback of the scaled output error proposed by tin and Unbehauen is employed and the forgetting factor is varied in adaptation process for avoiding the accumulation of the estimation error for additive noise . The proposed algorithm has the good convergence property without the parameter estimation error under the existence of mea-surement noise.

  • PDF

방사선치료계획 정도관리 방법에 따른 신뢰도 평가 (Reliability estimation about quality assurance method of radiotherapy planning)

  • 김정호;김가중;유세종;김기진
    • 대한안전경영과학회지
    • /
    • 제17권1호
    • /
    • pp.119-124
    • /
    • 2015
  • According as radiation therapy technique develops, standardization of radiation therapy has been complicated by the plan QA(Quality Assurance). However, plan QA tools are two type, OADT (opposite accumulation dose tool) and 3DADT (3 dimensional accumulation dose tool). OADT is not applied to evaluation of beam path. Therefore tolerance error of beam path will establish measurement value at OADT. Plan is six beam path, five irradiation field at each beam path. And beam path error is 0 degree, 0.2 degree, 0.4 degree, 0.6 degree, 0.6 degree, 0.8 degree. Plan QA accomplishes at OADT, 3DADT. The more path error increases, the more plan QA error increases. Tolerance error of OADT path is 0.357 using tolerance error of conventional plan QA. Henceforth plan QA using OADT will include beam path error. In addition, It will increase reliability through precise and various plan technique.

Analysis of Variation for Drainage Structure with Flow Direction Methods Based on DEM

  • Meiyan, Feng;Kahhoong, Kok;Kim, Joo-Cheol;Kwansue, Jung
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2018년도 학술발표회
    • /
    • pp.325-325
    • /
    • 2018
  • The main purpose of this study is to suggest the more reliable flow direction methods within the framework of DEM by investigating the existing methodologies. To this end SFD(single flow direction method), MFD(multiple flow direction method) and IFD(Infinite flow direction method) are applied to determination of flow direction for water particles in Jeonjeokbigyo basin, and then assessed with respect to the variation of flow accumulation. As the main results the different patterns of flow accumulation are found out from each application of flow direction methods. As the flow dispersion increases on DEM contributing areas to outlet grow in sequence of SFD, IFD, MFD but contribution of individual pixels into outlet decreases. Especially MFD and IFD tend to make additional hydrologic abstraction from rainfall excess due to the flow dispersion within flow paths on DEM. Based on parameter estimation for power law distribution by maximum likelihood flow accumulation can be thought of as scale invariance factor. Combination of several flow direction methods could give rise to the more realistic water flow on DEM through separate treatment of flow direction methods for dispersion and aggregation effects of water flow within different topographies.

  • PDF

Enhanced Coulomb Counting Method for State-of-Charge Estimation of Lithium-ion Batteries based on Peukert's Law and Coulombic Efficiency

  • Xie, Jiale;Ma, Jiachen;Bai, Kun
    • Journal of Power Electronics
    • /
    • 제18권3호
    • /
    • pp.910-922
    • /
    • 2018
  • Conventional battery state-of-charge (SoC) estimation methods either involve sophisticated models or consume considerable computational resource. This study constructs an enhanced coulomb counting method (Ah method) for the SoC estimation of lithium-ion batteries (LiBs) by expanding the Peukert equation for the discharging process and incorporating the Coulombic efficiency for the charging process. Both the rate- and temperature-dependence of battery capacity are encompassed. An SoC mapping approach is also devised for initial SoC determination and Ah method correction. The charge counting performance at different sampling frequencies is analyzed experimentally and theoretically. To achieve a favorable compromise between sampling frequency and accumulation accuracy, a frequency-adjustable current sampling solution is developed. Experiments under the augmented urban dynamometer driving schedule cycles at different temperatures are conducted on two LiBs of different chemistries. Results verify the effectiveness and generalization ability of the proposed SoC estimation method.