• 제목/요약/키워드: Post-classification

검색결과 382건 처리시간 0.031초

Digital Change Detection by Post-classification Comparison of Multitemporal Remotely-Sensed Data

  • Cho, Seong-Hoon
    • 대한원격탐사학회지
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    • 제16권4호
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    • pp.367-373
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    • 2000
  • Natural and artificial land features are very dynamic, changing somewhat repidly in our lifetime. It is important that such changes are inventoried accurately so that the physical and human processes at work can be more fully understood. Change detection is a technique used to determine the change between two or more time periods of a particular object of study. Change detection is an important process in monitoring and managing natural resources and urban development because it provides quantitative analysis of the spatial distribution in the population of interest. The purpose of this research is to detect environmental changes surrounding an area of Mountain Moscow, Idaho using Landsat Thematic Maper (TM) images of (July 8, 1990 and July 20, 1991). For accurate classification, the Image enhancement process was performed for improving the image quality of each image. A SPOT image (Aug. 14, 1992) was used for image merging in this research. Supervised classification was performed using the maximum likelihood method. Accuracy assessments were done for each classification. Two images were compared on a pixel-by-pixel basis using the post-classification comparison method that is used for detecting the changes of the study area in this research. The 'from-to' change class information can be detected by post classification comparison using this method and we could find which class change to another.

상향식 계층분류의 최적화 된 병합을 위한 후처리분석과 피드백 알고리즘 (Reinforcement Post-Processing and Feedback Algorithm for Optimal Combination in Bottom-Up Hierarchical Classification)

  • 최윤정;박승수
    • 정보처리학회논문지B
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    • 제17B권2호
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    • pp.139-148
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    • 2010
  • 본 논문은 자동화된 분류시스템의 성능향상을 위한 것으로 오분류율이 높은 불확실성이 강한 문서들의 범주결정방식을 개선하기 위한 후처리분석 방법과 피드백 알고리즘을 제안한다. 전통적인 분류시스템에서 분류의 정확성을 결정하는 요인으로 학습방법과 분류모델, 그리고 데이터의 특성을 들 수 있다. 특성들이 일부 공유되어 있거나 다의적인 특성들이 풍부한 문서들의 분류문제는 정형화된 데이터들에서 보다 심화된 분석과정이 요구된다. 특히 단순히 최상위 항목으로 지정하는 기존의 결정방법이 분류의 정확도를 저하시키는 직접적인 요인이 되므로 학습방법의 개선과 함께 분류모델을 적용한 이후의 결과 값인 순위정보 리스트의 관계를 분석하는 작업이 필요하다. 본 연구에서는 경계범주의 자동탐색기법으로 확장된 학습체계를 제안한 이전 연구의 후속작업으로써, 최종 범주를 결정하기까지의 후처리분석 방법과 이전의 학습단계로 피드백하여 신뢰성을 높일 수 있는 알고리즘을 제안하고 있다. 실험결과에서는 제안된 범주결정방식을 적용한 후 1회의 피드백을 수행하였을 때의 결과들을 단계적이고 종합적으로 분석함으로써 본 연구의 타당성과 정확성을 보인다.

위성영상을 이용한 토지이용 변화 검색기법 비교연구 (Comparison of Land Use Change Detection Methods with Satellite Image)

  • 박순호;김우관
    • 한국지역지리학회지
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    • 제5권1호
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    • pp.137-150
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    • 1999
  • 우리나라에서 위성자료를 이용한 토지이용에 관한 연구는 현황분석이 중심이고, 토지이용 변화에 관한 연구는 분석기법에 대한 적실성 평가 없이 특정기법이 적용되어 왔다. 본 연구는 도시지역의 토지이용 변화 검색에 많이 활용되고 있는 다섯 가지 토지이용 변화 검색기법을 선정하여 대구광역시 북구를 사례로 각 검색기법의 정확도를 비교 분석하였다. 핵심데이터는 1994년과 1997년에 촬영한 Landsat TM영상과 항공사진이다. 위성자료를 이용한 토지이용 변화검색에는 pre-classification comparison method가 post-classification comparison method보다 효과적이었다. Pre-classification comparison methods 중에서는 image differencing method가, 특히 임계치 1.0에서의 image differencing method의 DIF2 변화이미지의 경우가 가장 정확도가 높게 나타났다.

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Post-processing Technique for Improving the Odor-identification Performance based on E-Nose System

  • Byun, Hyung-Gi
    • 센서학회지
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    • 제24권6호
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    • pp.368-372
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    • 2015
  • In this paper, we proposed a post-processing technique for improving classification performance of electronic nose (E-Nose) system which may be occurred drift signals from sensor array. An adaptive radial basis function network using stochastic gradient (SG) and singular value decomposition (SVD) is applied to process signals from sensor array. Due to drift from sensor's aging and poisoning problems, the final classification results may be showed bias and fluctuations. The predicted classification results with drift are quantized to determine which identification level each class is on. To mitigate sharp fluctuations moving-averaging (MA) technique is applied to quantized identification results. Finally, quantization and some edge correction process are used to decide levels of the fluctuation-smoothed identification results. The proposed technique has been indicated that E-Nose system was shown correct odor identification results even if drift occurred in sensor array. It has been confirmed throughout the experimental works. The enhancements have produced a very robust odor identification capability which can compensate for decision errors induced from drift effects with sensor array in electronic nose system.

선분류 후비교법을 이용한 간석지의 토지피복 변화 및 패턴 분석 - 태안반도 지역을 사례로 - (The Land-cover Changes and Pattern Analysis in the Tidal Flats Using Post-classification Comparison Method: The Case of Taean Peninsula Region)

  • 장동호;김찬수;박지훈
    • 대한지리학회지
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    • 제45권2호
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    • pp.275-292
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    • 2010
  • 이 연구는 위성영상 자료(1972~2008년)를 이용하여 인위적인 환경변화에 따른 태안반도 간석지의 토지피복 변화를 시계열분석하고, 그 변화 패턴을 고찰하고자 하였다. 선분류 후비교법을 이용한 시기별 토지피복 변화를 분석한 결과, 1972년에서 2008년 사이에 태안반도 간석지의 토지피복은 갯벌에서 습지, 습지에서 논으로의 변화가 발생하였다. 세부적인 토지피복 변화 패턴을 분석하기 위해 변형된 선분류 후비교법을 이용하여 각각의 영상을 분석한 결과 태안반도 간석지는 갯벌 $\rightarrow$ 습지 호수 및 염전 $\rightarrow$ 나대지 $\rightarrow$$\rightarrow$ 나대지로 변하였음을 분석할 수 있었다. 선분류 후비교법의 적용을 위해서는 각 영상의 정확한 분류가 반드시 요구되는데, 분류된 영상의 전체정확도는 평균 95.33%로 나타났고, 카파값은 평균 0.941로 나타났다.

Stranc 분류법에 따른 비골골절 정복술 후 합병증 (Complications of the Nasal Bone Fractures according to the Stranc Classification)

  • 이준호;박원용;남현재;김용하
    • 대한두개안면성형외과학회지
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    • 제9권2호
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    • pp.62-66
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    • 2008
  • Purpose: Although nasal fractures are often discussed as minor injuries but the incidence of post-traumatic nasal deformity remains high. For decrease the incidence of post-traumatic nasal deformity which require the guideline to optimize the management of acute nasal bone fracture. The aim of this study is analysis of post-traumatic nasal deformity according to Stranc classification. Method: We reviewed 310 patients with nasal bone fracture treated at our hospital from January of 2005 to December of 2006. Result: Post-traumatic complication were divided septal deviation, nasal bone deformity, temporary hyposmia and synechia. Nasal bone deformity include nasal bone deviation, hump, flat nose and minimal nasal bone irregularity. The incidence of total complication rate was 36.4%. The most common complication was nasal deformity(22.9%) followed by septal deviation(19.7%). The most common complication was septal deviation(20%) in frontal impact. The most common complication was nasal deformity(19.5%) in lateral impact. In frontal impact, the incidence of complication rate was plane II(68.8%) followed by plane I(29.9%) and plane III(16.7%). In lateral impact, the incidence of complication rate was plane II (78.8%) followed by plane III(61.5%) and plane I(42.7%). Conclusion: This result can be used to improve longterm results and to reduce the incidence of post-traumatic nasal deformity by predict complication of nasal bone fracture according to Stranc classification.

임상진단명에 따른 질병분류체계 구축모형 개발 - 안과를 대상으로 - (Development of Construction Model of Disease Classification on Clinical Diagnosis in Ophthalmology)

  • 서진숙;신희영;기창원
    • 한국의료질향상학회지
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    • 제10권2호
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    • pp.204-215
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    • 2003
  • Background : ICD-10 Classification, which is used domestically as well as internationally, has limited use in the clinical practice since it is developed for at disease statistics and epidemiology. Therefore, the purposes of this study were to improve the quality of diagnosis by constructing a new disease classification based on the diagnoses doctors currently make in the clinical setting and connecting this classification with OCS and EMR, and to meet the demands of doctors for high quality medical study data in medical research. Methods : The specialists in each ophthalmic subfield collected clinical diagnoses and abbreviations based on the ophthalmology textbooks and confirmed the classifications. Total number of clinical diagnoses collected was totaled 672, for which ideal diagnoses had been selected and a new model of disease classification model in connection with ICD-10 was constructed. The constructed classification of clinical diagnoses consisted of six steps: the first step was the classification by ophthalmic subspecialty field; the second to fifth steps were the detailed classification by each specialty field; the sixth step was the classification by site. Results : After introducing the new disease classification, research on the use and a pre-post comparison was conducted. The result from the research on the use of the clinical diagnoses in inpatient and outpatient care has shown a gradually increasing tendency. From the pre-post comparison of EMR discharge summary diagnoses, the result demonstrated that the diagnosis was stated correctly and in detail. Since the diagnosis was stated correctly, code classification became correct as well, which makes it possible to construct high quality medical DB. Conclusion : This construction of clinical diagnoses provides the medical team with high quality medical information. It is also expected to increase the accuracy and efficiency of service in the department of medical record and department of insurance investigation. In the future, if hospitals wish to construct a classification of clinical diagnosis and a standard proposal of clinical diagnosis is presented by a medical society, the standardization of diagnosis seems to be possible.

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부동산 금융소비자 보호 체계의 평가 기준 간 중요도 분석: AHP 기법을 활용하여 (An Analysis Of The Importance Of The Evaluation Criteria Of The Real Estate Financial Consumer Protection System - Utilizing The AHP Technique)

  • 이연재;신승우
    • 아태비즈니스연구
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    • 제13권3호
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    • pp.227-243
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    • 2022
  • Purpose - This study surveyed real estate financial consumers and financial company staff regarding the components of the financial consumer protection system to seek detailed improvement plans for the Financial Consumer Protection Act. Design/methodology/approach - The Analytic Hierarchy Process (AHP) technique is applied. Findings - Both consumers and staff highly evaluated the importance of the preventive measures in the main classification factors. Regarding the sub-classification factors of preventive measures, consumers emphasized the responsible management of investment staff and financial institutions; however, the staff stressed the principle of effectiveness and efficiency. Regarding the elements of ex-post remedies, consumers answered that fast remedy would have a significant effect. At the same time, staff believed that punitive measures hinder free trading and investment activities. Regarding the sub-sub classification factors of prevention measures, the consumers value responsible management of staff and financial companies, while the staff tend to prefer the importance of the self-regulatory governance. Research implications or Originality - Based on the above results, financial regulatory authorities should find a balance between preventive and ex-post components once focusing on preventative measures. Our paper is one of the first research findings in this field of financial consumer protection system in Korea.

A STUDY ON IDENTIFICATION OF URBAN CHARACTERISTIC USING SPATIAL ARRANGEMENT METHOD

  • Chou, Tien-Yin;Kuo, Ching-Yi
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.984-987
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    • 2003
  • In order to rapidly catch up urban region’s detailed land-use or land-cover information; this research used the post-classification algorithm (Spatial Reclassification Kernel: SPARK) to create a land-use map of Taichung City. We discussed the urban land-use classification model with the IKONOS images. The conclusions may be distinguished as follows:(a) Using the Maximum-Likelihood algorithm to classify seven broad land-cover categories. The overall accuracy in this stage achieves 92.72% and Kappa coefficient will be obtained 0.91; and (b) Using the SPARK method to classify images for detect the land-use, the overall accuracy achieves higher 89.64% and Kappa coefficient will be 0.86. To conclude, the research process in this study can fully and carefully describe local land-use pattern and assist the demand of land management and resources planning reference.

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후처리를 이용한 환경음 인식 성능 개선 (Improvement of Environmental Sounds Recognition by Post Processing)

  • 박준규;백성준
    • 한국콘텐츠학회논문지
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    • 제10권7호
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    • pp.31-39
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    • 2010
  • 본 연구에 사용된 환경음은 9 가지 상황으로 구분하였으며 생활 속에서 인간의 이동에 따라 변화하는 실제 환경음과 동일한 테스트 데이터 셋을 이용하였다. 실제 환경에서 녹음된 데이터는 Pre-emphasis, Hamming window를 이용하여 전처리하고 MFCC (Mel-Frequency Cepstral Coefficients) 방식으로 특징을 추출한 후 GMM (Gaussian Mixture Model)을 이용하여 분류 실험을 행했다. 후처리가 없는 GMM은 프레임 별로 판정하므로 분류 결과를 보면 상황이 갑자기 변화하는 이상 결과가 나타난다. 이에 본 연구에서는 인접한 프레임 별 확률 값 혹은 분류 순위를 이용해서 갑작스런 상황 변화가 발생하지 않도록 하는 후처리 방식을 제안하였다. 실험 결과에 따르면 GMM 분류방식에 인접 프레임들의 사후확률 값을 이용하는 후처리방법을 적용한 경우 후처리를 적용하지 않은 경우에 비해 10% 이상 평균 인식률이 개선되는 것을 확인할 수 있었다.