• 제목/요약/키워드: edge decision

검색결과 156건 처리시간 0.02초

확장 QR-RLS 알고리즘을 이용한 시스토릭 어레이 구조의 결정 궤환 등화기 (A Systolic Array Structured Decision Feedback Equalizer based on Extended QR-RLS Algorithm)

  • 이원철
    • 한국통신학회논문지
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    • 제29권11C호
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    • pp.1518-1526
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    • 2004
  • 본 논문은 확장 QR-RLS 알고리즘을 이용한 시스토릭 어레이 구조를 갖는 적응 결정 궤환 등화기에 대해서 소개한다. 무선 이동 통신 시스템의 경우 빠른 시변환 채널로 인해 고속의 수렴 특성을 갖는 등화기가 필수적으로 요구된다. 최근에 이러한 성질을 만족하는 QR-RLS 알고리즘 기반의 등화기가 소개되었으며, RLS 알고리즘이 갖는 높은 수렴 속도와 시스토릭 어레이의 병렬 파이프라인 형태로 구현 가능함으로 인해 계산상의 높은 효율성을 가진다. 그러나 일반적인 QR-RLS 알고리즘은 별도의 등화기 가중치 추출과정을 필요로 하며, 이로 인해 적응 처리 과정을 완전한 파이프라인 형태로 수행하기는 어렵다. 본 논문에서는 확장 QR-RLS 알고리즘을 기반으로 제곱근 연산을 배제한 계산과정을 통해 채널 출력의 입력으로부터 가중치 갱신까지 완전환 파이프라인 방식으로 처리가 가능한 시스토릭 어레이 구조의 결정 궤환 등화기를 소개한다.

영역 성장법을 기반으로 자동적인 임계치 설정을 이용한 미세 석회화 추출 (Microcalcification Extraction by Using Automatic Thredholding Based on Region Growing)

  • 원철호;권용준;이정현;박희준;임성운;김명남;조진호
    • 대한의용생체공학회:의공학회지
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    • 제25권4호
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    • pp.235-242
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    • 2004
  • 본 논문에서는 영역 성장법을 기반으로 자동적인 임계치 설정에 의하여 미세 석회화를 추출하는 방법을 제안하였다. 미세 석회화 후보 영역에서 임계치를 반복적으로 증가시키면서 국부 최대치 화소로부터 영역을 성장시키고 명암 대비와 에지 선예도가 최대일 때 최적의 임계치가 결정됨으로써, 실제 영상에 있어서 효과적으로 미세 석회화를 추출할 수 있었다. 총 299개의 미세 석회화에 대하여 81.5%의 TP(true positive) 비율과 1.1개의 평균 FP(false positive) 개수를 가지는 만족할 만할 결과를 얻었으며, 진단 방사선 전문의의 조기 유방암 진단을 위한 보조 역할이 될 수 있음을 알 수 있었다.

Fuzzy Set을 이용한 피부반응 검사의 자동화 연구 (Automation of Skin Allergy Test using Fuzzy Set)

  • 심철;정병선;이명구;박민용
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1990년도 춘계학술대회
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    • pp.43-46
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    • 1990
  • Modern society is prevailed a lot of allergies. So, the allergy test is very important. There are many kinds of allergy test. A doctor usually uses skin allergy test among many allergy tests. However, little standadization and objectivity of grading-standard has been established in the skin allergy test. A measurement of the reaction area has been a major objective to perform skin allergy test. Recently, a doctor's method is to measure the reaction area after drawing a line that represents the reaction area on the skin. But this method differs slightly from the real reaction area and individual doctor's measurement is different, because the edge of the reaction area is obscure. In this paper, we propose a algorithm which is able to detect vague edges using the fuzzy set. The algorithm that detects the line and curve is proposed first. Here, the maximum value is calculated by comparing the membership function of the line and curve seperately. We also encode the direction of the line and curve by using 8-direction code. Then, we calculate the reaction area by measuring the pixels which are inside the reaction area. And finally the Allergy grade is decided by grading-standard, and we accomplish faster, the 80re accurate and objective allergy grade decision.

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An Empirical Study about the Influence of Country Personality and Product Involvement on Consumer's Purchase and Visit Intentions

  • Sousa, Ana;Nobre, Helena;Farhangmehr, Minoo
    • The Journal of Asian Finance, Economics and Business
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    • 제5권3호
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    • pp.65-72
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    • 2018
  • The purpose of this paper is to understand the influence of country personality dimensions and product involvement on European consumers purchase and visit intentions, considering the Portuguese context. The increasing economic globalisation has resulted in the reducing of trade barriers between nations and the availability of more foreign products and services across borders. Therefore, the place associations of these products and services might be regarded as a potential competitive differentiator in their respective markets. Despite the proliferation of literature devoted to assessing the effects of country-of-origin, the symbolic dimension of a country's image remains understudied. A questionnaire measuring country personality dimensions, product involvement, and consumer's purchase and visit intention was passed on a sample of 335 European consumers. Country personality indeed matters both positively and negatively. Findings show that while assiduousness positively influences consumer's visit intentions, wickedness has a negative influence on consumer's purchase intentions. Findings also reveal that product involvement has a positive significant influence on consumer's purchase and visit intentions. On developing marketing strategies, international marketers and governmental decision-makers should consider product involvement attributes and specific country personality traits to provide the country's products with a competitive edge, as well as to promote the country as a travelling destination.

도시하천 류축경의 시각적 선호요소 분석 (Analysis on Visual Preference Elements of Riverscape Axis)

  • 김용수;정계순;김수봉
    • 한국조경학회지
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    • 제26권2호
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    • pp.101-109
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    • 1998
  • Recently, improvement of the quality of urban riverscape environment has been emphasized not only by landscape architectural field but also by various professionals in planning and ecology. Regarding to this current movement, the aim of this paper is to highlight major visual elements of riverscape axis as a case study of Shinchon River in Taegu City to suggest some basic guidelines for arranging riverscape in urban area. The study was mainly based on Repertory Grid Development method which was developed in Japan. The method is consist of three steps such as decision of element landscape in study area for slide photos, selection of evaluation items for interview and obstraction of proper evaluation factors. The major findings through this study are as follows; 1) The 12 major visual elements which possibly improve riverscape, based on abstraction of proper evaluation factors, are Dunchi, surface of the water,, equipment of river, buildings near riverside, river vertical and horizontal facilities like bridge, fine view, riverbed, water plant, naturalness, water's edge line, harmony and street trees by order. 2) Total numbers of adjective which describe 12 common factors are 25, such as clean, open, stable, quiet, comfortable, friendly, bright, natural etc. In addition, Dunchi was described 337 times by various adjectives, surface of the water was 200 times and arrangement of river was 146 times which is similar result with the order of 12 influential common factors. 3) Therefore, Dunchi, surface of the water and equipment of river are three most important factors which could create better riverscape. These three factors implies us how we supply good quality of urban river environment for the urban residents.

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플랜트 프로젝트 리스크의 평가 및 관리시스템에 관한 연구 (Assessment and Management System for Various Risks in Plant Projects)

  • 안승규;조동환;허진혁;문승재;유호선
    • 플랜트 저널
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    • 제6권1호
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    • pp.56-63
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    • 2010
  • While the local plant market is reducing its volume, the plant market over the world since 2000s is rapidly expanding. The nation's construction companies, aggressively dedicated in launching out overseas plant market, increase the volume of orders in that sector, but there also are much difficulty in the project management as those projects ordered are gradually large scaled with more cutting-edge high-tech requirements along with comparatively higher risk. Though the local construction companies have developed their own types of measures to analyze the risk evaluation putting into practice, the specialized decision-making model for the overseas plant market or the risk measure understandable easily and applicable practically is not yet shown. This paper aims at providing the methodology to evaluate the risk by way of constructing the risk evaluation process in order to induce risk measuring elements through appropriate indexing system. Furthermore, through studying the risk management system, it aims to seek for a thorough risk management method from beginning of the project to the end.

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Coordination of Anti-Spoofing Mechanisms in Partial Deployments

  • An, Hyok;Lee, Heejo;Perrig, Adrian
    • Journal of Communications and Networks
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    • 제18권6호
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    • pp.948-961
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    • 2016
  • Internet protocol (IP) spoofing is a serious problem on the Internet. It is an attractive technique for adversaries who wish to amplify their network attacks and retain anonymity. Many approaches have been proposed to prevent IP spoofing attacks; however, they do not address a significant deployment issue, i.e., filtering inefficiency caused by a lack of deployment incentives for adopters. To defeat attacks effectively, one mechanism must be widely deployed on the network; however, the majority of the anti-spoofing mechanisms are unsuitable to solve the deployment issue by themselves. Each mechanism can work separately; however, their defensive power is considerably weak when insufficiently deployed. If we coordinate partially deployed mechanisms such that they work together, they demonstrate considerably superior performance by creating a synergy effect that overcomes their limited deployment. Therefore, we propose a universal anti-spoofing (UAS) mechanism that incorporates existing mechanisms to thwart IP spoofing attacks. In the proposed mechanism, intermediate routers utilize any existing anti-spoofing mechanism that can ascertain if a packet is spoofed and records this decision in the packet header. The edge routers of a victim network can estimate the forgery of a packet based on this information sent by the upstream routers. The results of experiments conducted with real Internet topologies indicate that UAS reduces false alarms up to 84.5% compared to the case where each mechanism operates individually.

한국프로농구구단의 생산성분석: DEA를 중심으로 (A Productive Analysis of Sports Organizations in Korean Basketball League: Focused on DEA)

  • 김선민
    • 대한안전경영과학회지
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    • 제15권2호
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    • pp.255-262
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    • 2013
  • Due to the competition between the various professional events, it is imperative for the team's management to improve efficiency by removing the inefficiencies of the professional team in order to gain a competitive edge. This study use different Data Envelopment Analysis (DEA) models to measure the efficiency of professional sport organizations. In this mathematical-analytical study, this study first reviews the related literature to analyze the input/output variables. In the end, the variables were detected and the data for this study were gathered from the Korean Basketball League (KBL). While previous studies examine relative efficiency of Korean Professional baseball teams by using CCR model, this study fully utilize the DEA method to investigate Korean professional sports organizations' operating problem. Thus, this study propose full results of DEA analysis such as efficiency score (overall, technical, and scale efficiency), slacks in inputs and outputs of inefficient organizations, Malmquist index) As a result, this study provides not only the exact productivity information of a team and a way of improving a firm's productivity with a decision maker.

탄성변형 에너지 기반 Hausdorff 거리를 이용한 개선된 객체검출 (An Improved Object Detection Method using Hausdorff Distance based on Elastic Deformation Energy)

  • 원보환;구자영
    • 한국컴퓨터정보학회논문지
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    • 제12권2호
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    • pp.71-76
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    • 2007
  • 주어진 영상 내에서 의미 있는 객체의 존재여부를 판단하는 객체검출과정은 컴퓨터 비전 시스템을 이용한 영상인식의 핵심요소 가운데 하나이다. 템플릿 정합 방식의 객체 검출방식에서 사용되어 얼굴 인식 등에서 좋은 성능을 보이는 Hausdorff 거리는 점의 집합으로 표현된 두 객체 사이의 다른 정도를 정의함으로써 주어진 모델과 가장 차이가 적은 객체를 검출하도록 한다. 본 논문에서는 일반적으로 사용되는 바와 같이 점의 집합이 영상의 에지를 검출하여 얻어진 경우, 에지가 가지고 있는 방향정보를 이용함으로써 검출의 정확성을 높일 수 있는 방법을 제안하고 있다. 일반적으로 사용되는 Euclidean 거리 대신에 방향을 가진 두 점을 일치시키는데 필요한 탄성에너지를 정의함으로써 검출의 정확성을 높이는 방법을 제시하고 있다.

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Bilateral 필터의 Sigma 편차를 이용한 차량 영상 Deblur 알고리즘 (Deblurring Algorithm for Vehicle Image Processing Using Sigma Variation of Bilateral Filter)

  • 손휘곤;김희석
    • 전기전자학회논문지
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    • 제19권2호
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    • pp.148-154
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    • 2015
  • 차량 전장시스템은 매 순간마다 정확한 인식을 통하여 사용자에게 정확한 경보를 전달해야 한다. 따라서 차량 영상 인식 알고리즘을 적용하기 위하여 빠른 전처리 시스템이 필요하다. 본 논문은 운전자 보조 시스템의 영상 처리를 목적으로 histogram equalization과 편차를 이용한 bilateral Filter를 사용하여 blur 영상을 보정하는 방법에 대해서 제안하였다. 제안한 시스템은 영상 스케일, 평활화, 노이즈 필터, 윤곽선 추출 순으로 총 5단계로 구성되며, bilateral filter의 과 값을 운전자 보조 시스템에서 나타나는 도로의 주행 현상에 적합하게 추출하여 10픽셀 이하의 blur를 기존의 방법들보다 빠르게 처리하였다. 실험 결과는 MATLAB을 사용하여 소요시간 및 PSNR을 구하였으며 기존의 방법과 비교하여 본 논문의 결과가 처리속도가 빠름을 입증하였다.