• 제목/요약/키워드: spatial weighting

검색결과 172건 처리시간 0.029초

계측용 공간필터의 가변적 다치화된 가중치 실현에 관한 연구 (A Study on the Realization of Variable Spatial Filtering Detector with Multi-Value Weighting Function)

  • 정준익;한영배;고현민;노도환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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    • pp.481-483
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    • 1998
  • In general, spatial filtering method was proposed to simplify measurement system through parallel Processing hardware. Spatial filtering is a method of detection that we can get a spatial pattern information, as we process a special space pattern, to say, as we process spatial parallel process by using the spatial weighting function. The important processing characteristics will be depended in according to how ire design a spatial weighting function, a spatial sensitive distribution. The form of the weighting function which is realized from the generally used spatial filtering is fixed and the weighting value was already became a binary-value. In this paper, we propose a new method in order to construct adaptive measurement systems. This method is a weighting function design to make multi-valued and variable.

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Integration of Current-mode VSFD with Multi-valued Weighting Function

  • Go, H.M.;Takayama, J.;Ohyama, S.;Kobayashi, A.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.921-926
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    • 2003
  • This paper describes a new type of the spatial filter detector (SFD) with variable and multi-valued weighting function. This SFD called variable spatial filter detector with multi-valued weighting function (VSFDwMWF) uses current-mode circuits for noise resistance and high-resolution weighting values. Total weighting values consist of 7bit, 6-signal bit and 1-sign bit. We fabricate VSFDwMWF chip using Rohm 0.35${\mu}$m CMOS process. VSFDwMWF chip includes two-dimensional 10${\times}$13 photodiode array and current-mode weighting control circuit. Simulation shows the weighting values are varied and multi-valued by external switching operation. The layout of VSFDwMWF chip is shown.

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공간시계열 모형의 칼만필터 추정과 예측 (Kalman-Filter Estimation and Prediction for a Spatial Time Series Model)

  • 이성덕;한은희;김덕기
    • Communications for Statistical Applications and Methods
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    • 제18권1호
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    • pp.79-87
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    • 2011
  • 공간적, 시간적으로 퍼져나가는 전염성이 강한 질병인 수두자료를 이용하여 공간 시계열 자료를 분석하는데 있어 일반적으로 알려진 ARIMA 모형에 적합하여 분석을 행하면 공간적인 정보를 반영하지 못하기 때문에 기존에 시간만을 고려한 시계열 분석방법에 공간통계의 공간적 정보를 반영한 공간시계열 모형을 고려한다. 공간시계열 모형에서 공간의 위치 및 영향은 시계열 모형에 공간적 정보로써 가중치행렬을 더 함으로써 처리 가능해진다. 가중치행렬은 지리적으로 인접한 지역일수록 공간의존도가 높다는 것을 반영한 것이며 공간시계열 모형의 연구에서 가중치행렬은 인접한 지역들은 동일한 영향을 줄 것이라 가정하였다. 따라서 본 논문에서는 공간시계열 모형인 STARMA 모형과 STBL 모형에 대한 식별방법, 통계적 추론 및 예측력 비교에 대해 연구하였고 특히, 모수추정의 알고리즘 비교와 공간시계열 모형의 예측력 비교를 통해 Kalman-Filter 방법의 우수성을 보이고자 한다.

공간 가중치를 이용한 주거환경 개선지역 우선순위평가: 대구광역시 신천동을 사례로 (Evaluating Rebuilding Priority to Improve Residential Environment Using Spatial Weighting: A Case Study on Shinchun-Dong of Daegu Metropolitan City)

  • 손승휘;박기헌;엄정섭
    • 대한지리학회지
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    • 제43권6호
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    • pp.961-980
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    • 2008
  • 주거환경 개선 사업지역의 우선순위 평가는 담당자의 경험이나 직관, 또는 소수전문가들의 경험적 지식 등에 의존하고 있다. 수요자의 요구를 반영한 공간 가중치를 활용하여 주거환경 개선 사업의 우선순위를 평가하고자 본 연구가 수행되었다. 공간가중치 기반의 주거환경개선 사업 우선순위 평가는 기존의 미시적 인 데이터 에 의거한 평가보다 객관적이고 정량적 인 근거를 제시하는 도구로 활용될 수 있었다. 기존에 조사지점에만 국한된 통계 수치정보가 광역적인 주거환경개선 사업 우선순위 지역을 단시간에 제시하는 데 많은 한계가 있었으나 대용량의 공간 데이터와 다양한 형태의 데이터를 통합하는 GIS기법을 활용하여 주거환경 개선 사업의 우선순위 결정과정의 객관성을 확보할 수 있었다. 수작업에서는 담당자의 주관이 반영된 분석결과에 의거 사업 우선순위를 제시하더라도 그것을 쉽게 점검할 수 있는 방법이 마땅하지 않았다. 그러나 명확하고 체계적인 GIS 분석과정 때문에 그러한 오류를 예방할 수 있었으며 분석결과가 객관적으로 제시될 수 있었다. 사업 우선순위 관련 민원발생시 관련 자료를 곧바로 제공하고 민원을 신속히 해결할 수 있을 것으로 사료된다.

공간구문론에의 거리가중개념 적용에 관한 심층 연구 (An In-depth Study on Applying Metric Weighting to Space Syntax)

  • 김민석;박근송
    • 대한건축학회논문집:계획계
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    • 제34권12호
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    • pp.49-54
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    • 2018
  • Applying metric(distance) factor as weighting to spatial syntax is known to not contribute to the explanatory power for the human movement behavior as compared to the geometric(angle) factor according to the negative results of several related studies. However, Kim & Piao (2017) assumed that there is not a problem of the metric factor itself but a problem of the way of applying the metric factor as weighting, and presented a new possibility of the metric factor as weighting by proposing and verifying the methods of applying the metric weighting, which are different from the existing ones. The purpose of this study is to propose advanced methods of applying the metric weighting to space syntax, and to verify whether they contribute to the improvement of explanatory power of space syntax analysis. In this paper, we propose functions for combined depth of distance-step that combine the distance-weighted depth function with the step depth function and apply them to axial segment analysis to check the improvement of explanatory power of them.

AGRICULTURAL DROUGHT RISK ASSESSMENT USING REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM

  • Narongrit, Chada;Yeesoonsang, Seesai
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.991-993
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    • 2003
  • The 4 sets of environmental variables dealing with meteorology, hydrology and physiography were analyzed to generate a spatial drought risk index of Phitsanulok province of Thailand. The analysis of K-mean and discriminant were applied to the set of the selective drought variables for grouping each of spatial variable set into 4 classes. The obtained 4 classes, based on group statistics, were thus recoded in the meaning of no risk, low risk, moderate risk, and high risk. The regression coefficient between recoded classes and a set of the selective environmental variables were then applied as spatial variable weighting on thematic dataset in GIS spatial analysis. The results showed that the weighting score of drought variable was highest in meteorological variable compared to other variables.

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WSM-AHP법의 정식화를 통한 주거지 확산 지역의 최적 잠재력 표면의 추정 (Estimating Optimal Potential Surface for Spatial Expansion of Built-up Area by Formulating WSM-AHP Method)

  • 김대식
    • 한국농공학회논문집
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    • 제50권3호
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    • pp.91-104
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    • 2008
  • This study developed the WSM (weighted scenario method)-AHP method that can optimize the weighting value for multi-criteria to make GIS grid-based potential surface. The potential surface has been used to simulate urban expansion using distributed cellular automata model and to generate land-use planning as basic data. This study formulated the WSM-AHP method in mathematically and applied to test region, Suwon city, which located on south area from Seoul. WSM-AHP method generates potential map for each pair of weighting value for all criteria, which one criterion is weighted with high weighting value and the others use low weighting value, considering that the summation for all criteria weighting values should be "1". The potential change rate to the step of weighted scenario for weighting value of criteria is standardized like AHP intensity matrix in this study. From the standard potential change rate, WSM-AHP intensity matrix is completed, and then the optimal weighting value is calculated from the maximum eigenvector of the WSM-AHP matrix, according to the new WSM-AHP method developed in this study. The applied results of new method showed that the optimal weighting value from WSM-AHP is more resonable than the general AHP specialists' evaluation for weighting value. The another new finding of this study is to suggest the deterministic approach to optimize the weighting value for the distributed CA model, which is used to find new city area and to generate rational land-use planning.

GIS와 RS를 이용한 도시확산 포텐셜 평가기법의 개발 (Development of a potential evaluation method for urban expansion using GIS and RS technologies)

  • 김대식;정하우
    • 농촌계획
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    • 제10권3호
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    • pp.41-51
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    • 2004
  • This study aims to develop a potential evaluation method for urban spatial expansion using remote sensing (RS) and geographic information system (GIS). A multi-criteria evaluation method with several criteria and their weighting values was introduced to evaluate the score and quantification of the potential surface around the existing cities. The six criteria with one geographic factor, slope, and five accessibility factors, time distance from center of the city, national road, interchange of expressway, a big city, and station, were defined for the potential. RS techniques were applied for classification of the actual urban expansion maps between two periods, and GIS functions were used for score of accessibility criteria with a distance decay function from geographic, road and several point maps, which was developed in this study. The new methodology was applied to a test area, Suwon, between 1986 and 1996. In order to optimize the six weighting values, this study made new findings to search the optimal combination of the weighting values from new methodology, weighted scenario method for intensity order (WSM), combined with intensity order and AHP method, including a trial and error method for sensitivity analysis to make the intensity order. The optimal combination of the weighting values by the new method generated the optimal potential surface, considering spatial trend of urban expansion in the test area.

면적평균강우량의 추정 및 추정오차 (Estimation of Area Average Rainfall Amount and Its Error)

  • 유철상;정광식
    • 한국수자원학회논문집
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    • 제34권4호
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    • pp.317-326
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    • 2001
  • 본 연구에서는 산술평균법, Thiessen의 가중평균법 및 추정이론에 근거한 최적가중치를 이용하는 방법으로 면적평균강우량을 계산하고 각각의 경우에 대해 오차를 평가해 보았다. 본 연구에서는 남한강 유역의 영월 상류지역을 대상으로 하여 수행하였으며 그 결과를 정리하면 다음과 같다. 먼저 유역 내 강우계가 균등하게 분포되어 있는 경우 산술평균법이나 Thiessen의 가중평균법을 이용한 결과에는 큰 차이가 없다. 그러나 이들 두 방법은 강우의 공간적 변동성을 고려하지 못하는 이유로 특히 강우의 변동성이 큰 경우 면적평균강우의 추정에 큰 오차를 내포할 수 있다. 이러한 추정오차는 강우의 공간적 변동성을 고려하는 추정이론에 근거한 방법에 비해 매우 큰 값을 나타냄을 확인하였다. 따라서, 우리나라의 여름철 강우처럼 그 공간적 변동성이 큰 경우에 기존의 산술평균법이나 Thiessen의 가중평균법은 상당히 큰 추정오차를 내포할 수 있음을 파악할 수 있으며 따라서 이를 고려할 수 있는 방법, 예를 들어 현재 대유역에 적용되고 있는 등우선법이나 본 연구에서 사용된 추정이론에 근거한 방법이 적용되어야 할 것으로 판단된다.

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Speckle noise reduction in SAR images using an adaptive wavelet Shrinkage method

  • Kim, Kwang-Yong;Jeong, Soo;Kim, Kyung-Ok
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.303-307
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    • 2002
  • Although Synthetic Aperture Radar(SAR) is a very powerful and attractive tool, automatic interpretation of SAR images is extremely difficult because of several reason. Spatially, speckle noise reduction in SAR images is important step to interpret the SAR image at the preprocessing step. The speckle noise in SAR images is modeled to be multiplicative, and therefore, a signal-dependent noise. So, it has deflated many image-denoising algorithms that are based on additive noise model. In this paper, we propose an adaptive wavelet shrinkage method for speckle noise reduction in SAR images by analyzing the high frequency level in detail. We first decompose minutely the high frequency level to analyze the noise level. And then, we determine the weighting threshold value per the level, and layer. Finally, using those weighting threshold, we produce the efficient wavelet shrinkage method. So, this method not only reduces the speckle noise, but also preserves image detail and sharpness.

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