• 제목/요약/키워드: small-area estimation

검색결과 332건 처리시간 0.027초

Estimation of surface color with use of subjective feeling: On the influence of contrast by complementary color

  • Sakamoto, Kazuyoshi;Wada, Mitsuyoshi;Min, Byung-Chan
    • 한국감성과학회:학술대회논문집
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    • 한국감성과학회 2002년도 춘계학술대회 논문집
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    • pp.261-265
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    • 2002
  • The unique colors of paper, that is, blue, green, red, and yellow were used in the estimation of color from the subjective feeling. The monochrome with unique color or the unique color surrounded with the background color was presented. Subject gazed the monochrome or the unique color, which was called target color. The target and background color were the complementary color each other. The various ratios of the area of gazed color and background were taken. Subject answered the level of subjective feeling consisted of pair of adjective items for unique color presented. With the use of the subjective feeling fer the target color presented, the estimation of the unique color was carried out due to Fuzzy theory and neural networks. The results of color difference between unique color presented and the estimated color gave very small value for the case without background, while the results of the case with background color depended on the ratio of area of presented color and background color till the ration of 2:1, The relation showed the Kirschman's law. The color difference saturated in the increase of area of background with the ratio more than 2:1.

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On Estimating the Odds Ratio between Male and Female Unemployment Rate in Small Area

  • Park, Jong-Tae
    • Journal of the Korean Data and Information Science Society
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    • 제17권4호
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    • pp.1029-1039
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    • 2006
  • There are different kinds of methods to estimate the odds ratio for unemployment statistics in small areas, namely, the composite estimator, the Woolf estimator and the Mantel-Haenszel estimator. We can compare the reliability of these estimators according to the bias and MSE. The estimation procedures considered by this study have been applied to estimate the bias and MSE of the odds ratio between the male and female unemployment rate in some small areas. The Woolf estimator or the Mantel-Haenszel estimator is more stable than the composite estimator, but all these three estimators are similar to each other from the aspect of efficiency.

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소구경 코어에 의한 콘크리트 압축강도 추정에 미치는 실험인자의 영향에 관한 연구 (A Study on the Influencing Factors on the Estimation of Compressive Strength by Small Size Core)

  • 한민철;김기정;백병훈;한천구;송성진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.361-364
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    • 2002
  • This paper discusses the influencing factors such as coring position, height to diameter ratio of core specimen(h/d) and coring torque on the strength estimation of concrete by small site coring method in order to verify the validities of small size core method. According to results, as for the influence of drilling position, when core specimens are obtained from the place parallel to placing direction, compressive strength of core specimens are higher than those perpendicular to placing direction. This is due to the loss of the area of core specimen perpendicular to plating direction by bleeding. And in case of $\phi$ 24mm core specimen, when vertical drilling against placing direction is taken. compressive strength of core specimen obtained at the bottom of the structure is higher than that at the top of the structure. As for the influence of height to depth ratio, as h/d ratio increases compressive strength shows to be decreased. As for the influences of rotation speed of drilling machine, as its speed goes up, compressive strength decreases, regardless of core diameter.

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지역별 제조업의 비용함수 추정 (Cost Function Estimation of Regional Manufacturing Industries in Ko-rea)

  • 김상호;손영엽
    • 지역연구
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    • 제11권2호
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    • pp.1-17
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    • 1995
  • Regional production structres are investigated through an estimation of three-input(labor, capital and material) translog cost function. The estimation uses the pooled data in which time series data of 1970-1990 are combined with cross-sectional data corresponding to firm sizes. The empirical finding are the following: (1) the factors are Allen substitutes each otner in general except Pusan and a couple of regionss, and (2) estimates are very small in its absolute value irrespective of the regions. The low elasticity estimates of this study implies that substitytability among the three inputs are very weak in the regional manufacturing production compared to that in the national production. Seoul-Kyungki metropolitan area produces not only the smallest elasticities but relatively stable estimates without much fluctuation between the sub-regions of the area.

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고밀도 지상강우관측망을 활용한 서울지역 정량적 실황강우장 산정 (Quantitative Precipitation Estimation using High Density Rain Gauge Network in Seoul Area)

  • 윤성심;이병주;최영진
    • 대기
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    • 제25권2호
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    • pp.283-294
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    • 2015
  • For urban flash flood simulation, we need the higher resolution radar rainfall than radar rainfall of KMA, which has 10 min time and 1km spatial resolution, because the area of subbasins is almost below $1km^2$. Moreover, we have to secure the high quantitative accuracy for considering the urban hydrological model that is sensitive to rainfall input. In this study, we developed the quantitative precipitation estimation (QPE), which has 250 m spatial resolution and high accuracy using KMA AWS and SK Planet stations with Mt. Gwangdeok radar data in Seoul area. As the results, the rainfall field using KMA AWS (QPE1) is showed high smoothing effect and the rainfall field using Mt. Gwangdeok radar is lower estimated than other rainfall fields. The rainfall field using KMA AWS and SK Planet (QPE2) and conditional merged rainfall field (QPE4) has high quantitative accuracy. In addition, they have small smoothed area and well displayed the spatial variation of rainfall distribution. In particular, the quantitative accuracy of QPE4 is slightly less than QPE2, but it has been simulated well the non-homogeneity of the spatial distribution of rainfall.

Stream flow estimation in small to large size streams using Sentinel-1 Synthetic Aperture Radar (SAR) data in Han River Basin, Korea

  • Ahmad, Waqas;Kim, Dongkyun
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2019년도 학술발표회
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    • pp.152-152
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    • 2019
  • This study demonstrates a novel approach of remotely sensed estimates of stream flow at fifteen hydrological station in the Han River Basin, Korea. Multi-temporal data of the European Space Agency's Sentinel-1 SAR satellite from 19 January, 2015 to 25 August, 2018 is used to develop and validate the flow estimation model for each station. The flow estimation model is based on a power law relationship established between the remotely sensed surface area of water at a selected reach of the stream and the observed discharge. The satellite images were pre-processed for thermal noise, radiometric, speckle and terrain correction. The difference in SAR image brightness caused by the differences in SAR satellite look angle and atmospheric condition are corrected using the histogram matching technique. Selective area filtering is applied to identify the extent of the selected stream reach where the change in water surface area is highly sensitive to the change in stream discharge. Following this, an iterative procedure called the Optimum Threshold Classification Algorithm (OTC) is applied to the multi-temporal selective areas to extract a series of water surface areas. It is observed that the extracted water surface area and the stream discharge are related by the power law equation. A strong correlation coefficient ranging from 0.68 to 0.98 (mean=0.89) was observed for thirteen hydrological stations, while at two stations the relationship was highly affected by the hydraulic structures such as dam. It is further identified that the availability of remotely sensed data for a range of discharge conditions and the geometric properties of the selected stream reach such as the stream width and side slope influence the accuracy of the flow estimation model.

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소지역의 실업률에 대한 상대위험도의 추정에 관한 비교연구 (A comparison study on the estimation of the relative risk for the unemployed rate in small area)

  • 박종태
    • Journal of the Korean Data and Information Science Society
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    • 제20권2호
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    • pp.349-356
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    • 2009
  • 국내의 행정구역상 시군구 등과 같은 소지역에 있어서 실업률에 대한 남녀별 공통 상대위험도를 추정하는데, 추정방법으로 단순한 합동추정, 울프 방법에 기초한 가중추정과 잭나이프 추정들을 고려하고 이 추정 방법들의 효율성을 편의와 평균제곱오차의 개념을 통해서 비교하고자 한다. 이를 위해 2002년 12월 경기지역의 경제활동인구조사 자료를 이용하여 이 지역 내의 24개 시군단위 소지역들의 남녀별 실업률에 대한 상대위험도의 편의 및 평균제곱오차가 본 연구에서 제시된 추정절차에 의해 추정된다. 또한, 이들 추정치들의 안정성과 신뢰성은 상대편의와 상대오차제곱근을 통하여 비교된다. 추정결과 잭나이프 추정이 다른 두 추정들에 비해 매우 효율적임을 보였다.

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운동의 연속성을 이용한 고속 움직임 추정 기법에 관한 연구 (Fast Motion Estimation Algorithm Using the Continuity of Motion)

  • 송병철;임경원;나종범
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1995년도 학술대회
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    • pp.131-135
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    • 1995
  • As the search range increases, most fast ME algorithms can not keep the performance comparable to the full search BMA. In this paper, we propose a new fast motion estimation method which locates the small search area for a block of the current frame. This method is based on interframe correlation of motion vectors as well as intraframe correlation. Especially, the proposed algorithm outperforms other fast methods when the motion is very fast or complex. It drastically reduces computational complexity while maintaining good performance compared with the conventional FS-BMA.

질병지도 작성을 위해 공간모형을 이용한 소지역 추정 (Small area estimations for disease mapping by using spatial model)

  • 안대성;한준희;윤태호;김창훈;노맹석
    • Journal of the Korean Data and Information Science Society
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    • 제26권1호
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    • pp.101-109
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    • 2015
  • 행정구역상 읍/면/동 단위의 소지역 (small area)별로 질병위험의 차이에 대한 분석을 위해, 2005년 기준 서울 행정동을 기준으로 2005년부터 2008년까지 질병, 사고, 암 사망자료에 대한 표준화 사망률 (SMR; standardized mortality rate)을 고려하였다. 소지역 단위로 질병사망률을 직접 추정하는 것은 소지역 내 표본수가 작아, 개발 소지역 단위에서의 직접 계산된 SMR은 그 추정치의 정도 (precision) 확보가 어려운 문제점이 발생한다. 따라서, 본 연구에서는 각 소지역간 효과 추정을 위해 공간적 상관성 (spatial correlation)을 가지는 다단계 일반화 선형모형 (HGLM; hierarchical generalized linear models)을 고려하였다. 이를 통해, 서울지역 동별 주요 사망원인에 따른 공변량의 효과 및 추정된 SMR을 근거로 질병지도 결과를 제시하였다.

농촌지역 소규모 소택형습지의 유형분류 및 기능평가 연구 (The Type Classification and Function Assessment at Small Palustrine Wetland in Rural Areas)

  • 손진관;김남춘;강방훈
    • 한국환경복원기술학회지
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    • 제13권6호
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    • pp.117-131
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    • 2010
  • This study was conducted to utilize as basic information for the construction of conservation and estimation system for Palustrine wetland, which was badly managed and imprudently reclaimed, through the analysis of distribution characteristics and the estimation of conservation value for sample sites (eight wetlands) in rural area. As the result of wetland type classification, these wetlands was classified by 4 types (Permanent freshwater marshes/pools, ponds, Aquaculture ponds, and Seasonally flooded agricultural land) by Ramsar system, 3 types (Emergent Wetland, Aquatic Bed, and Scrub-Shrub Wetland) by NWI (Cowardin) System, 5 types (Farm Pond Depression, Under-flow wetland, Man-made Pond Depression, Abandoned Paddy Fields Wetland, and Reservoir Shore) by National Wetland's Categorical System, and 3 types (Aquatic Bed Wetland, Emergent Wetland, and Forested Wetland) by Lee (2000) System. These results suggest us developing the new type classification system for small Palustrine wetland in Korean rural areas. The score of function assessment (The Modified RAM) for small Palustrine wetlands was high at the wetlands nearby hills and rice paddy fields, and low at those nearby upper fields, which was mainly affected by land-use and vegetation. The functions as 'Flood/Storm Water Storage', 'Runoff Attenuation', 'Water Quality Protection' were resulted by the structural difference of inflow and outlet. Some functions as 'Wetland size', 'Wetland to immediate watershed ratio', 'Presence of boat traffic', 'Maximum water depth', 'Fetch of water's body' of RAM were not appropriate in evaluation of small wetlands in rural area. Which suggest us developing the new function assessment system for small Palustirne wetland in Korean rural areas.