• 제목/요약/키워드: Randomized

검색결과 5,105건 처리시간 0.042초

Assessment for Efficiency of Two-Stage Randomized Response Technique

  • Park, Kyung-Ho
    • Communications for Statistical Applications and Methods
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    • 제7권2호
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    • pp.427-433
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    • 2000
  • In this paper, we review several two-stage randomized response techniques for gathering self-report data when persons are asked sensitive question. Also efficiencies and privacy protections based on the two-stage randomized response procedures are compared. Finally, we find optimal parameter conditions.

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Historical Controls, Data Banks, and Randomized Trials in Clinical Research: A Review

  • Fleming Thomas R.
    • 대한예방의학회:학술대회논문집
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    • 대한예방의학회 1994년도 교수 연수회(역학)
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    • pp.265-269
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    • 1994
  • A brief review is presented of the strengths and weaknesses of historical controls, data banks, and randomized trials in the evaluation of clinical treatment. Use of pre randomized versus postrandomized informed consent is discussed. Recommendations are made for the development of an appropriate clinical research strategy.

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Randomized Hough 변환을 이용한 타원형 액적의 형상 검출 (Shape Detection of Ellipsoidal Droplets Using Randomized Hough Transform)

  • 추연준;강보선
    • 대한기계학회논문집B
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    • 제27권10호
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    • pp.1508-1515
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    • 2003
  • In this study, the image processing program for deducing parameters of the elliptic shape of the partially overlapped liquid droplets was developed using the randomized Hough transform and the parameter decomposition. The procedure for the shape detection consists of three steps. For the first step, the candidate centers of ellipses are determined by the geometric property of the ellipse. Next, the rest parameters are estimated by the randomized Hough transform. In the final step for the post-processing, optimally approximated parameters of ellipses are determined. The developed program was applied to the simulated overlapped ellipses, real overlapped droplets, and real spray droplets. The shape detection was very excellent unless there existed inherent problems in original images. Moreover, this method can be used as an effective separating method for the overlapped small particles.

반복시행된 확률화 응답(RRD) 모형의 독립조건 (Independence Condition in the Repeated Randomized Response Models)

  • 이관제;국세정
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2000년도 추계학술발표회 논문집
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    • pp.33-38
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    • 2000
  • Krishnamoorphy and Raghavarao(1993) invented exact binomial and asymptotically normal test procedures for truthful answering in the repeated randomized response models under the assumption that two repeated response measures are independent. Under the same assumption, Lakshmi and Raghavarao(1992) suggested asymptotic chi-square test for respondents' truthful answering in the same models. In this article we detect the factors and the conditions with which two response variables might be independent, and find the condition for independence in the repeated randomized response models with considering untruthful answer. But, the condition of independence make the randomized model no meaning. Under the assumption of conditional independence between two response variables, we can apply the same logical statements on deriving the tests for truthful answering in the repeated randomized response models as in Krishnamoorphy and Raghavarao(1993).

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Randomized Hough 변환을 이용한 타원형 액적의 형상 검출 (Shape Detection of Ellipsoidal Droplets Using Randomized Hough Transform)

  • 추연준;강보선
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1783-1788
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    • 2003
  • In this study, the image processing program for deducing parameters of the elliptic shape of the partially overlapped liquid droplets was developed using the randomized Hough transform and the parameter decomposition. The procedure for the shape detection consists of three steps. For the first step, the candidate centers of ellipses are determined by the geometric property of the ellipse. Next, the rest parameters are estimated by the randomized Hough transform. In the final step for the post-processing, optimally approximated parameters of ellipses are determined. The developed program was applied to the simulated overlapped ellipses, real overlapped droplets, and real spray droplets. The shape detection was very excellent unless there existed inherent problems in original images. Moreover, this method can be used as an effective separating method for the overlapped small particles.

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Novel Two-Level Randomized Sector-based Routing to Maintain Source Location Privacy in WSN for IoT

  • Jainulabudeen, A.;Surputheen, M. Mohamed
    • International Journal of Computer Science & Network Security
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    • 제22권3호
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    • pp.285-291
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    • 2022
  • WSN is the major component for information transfer in IoT environments. Source Location Privacy (SLP) has attracted attention in WSN environments. Effective SLP can avoid adversaries to backtrack and capture source nodes. This work presents a Two-Level Randomized Sector-based Routing (TLRSR) model to ensure SLP in wireless environments. Sector creation is the initial process, where the nodes in the network are grouped into defined sectors. The first level routing process identifies sector-based route to the destination node, which is performed by Ant Colony Optimization (ACO). The second level performs route extraction, which identifies the actual nodes for transmission. The route extraction is randomized and is performed using Simulated Annealing. This process is distributed between the nodes, hence ensures even charge depletion across the network. Randomized node selection process ensures SLP and also avoids depletion of certain specific nodes, resulting in increased network lifetime. Experiments and comparisons indicate faster route detection and optimal paths by the TLRSR model.

Randomized Scheme for Cognizing Tags in RFID Networks and Its Optimization

  • Choi, Cheon Won
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권4호
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    • pp.1674-1692
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    • 2018
  • An RFID network is a network in which a reader inquire about the identities of tags and tags respond with their identities to a reader. The diversity of RFID networks has brought about many applications including an inexpensive system where a single reader supports a small number of tags. Such a system needs a tag cognizance scheme that is able to arbitrate among contending tags as well as is simple enough. In this paper, confining our attention to a clan of simple schemes, we propose a randomized scheme with aiming at enhancing the tag cognizance rate than a conventional scheme. Then, we derive an exact expression for the cognizance rate attained by the randomized scheme. Unfortunately, the exact expression is not so tractable as to optimize the randomized scheme. As an alternative way, we develop an upper bound on the tag cognizance rate. In a closed form, we then obtain a nearly optimal value for a key design parameter, which maximizes the upper bound. Numerical examples confirm that the randomized scheme is able to dominate the conventional scheme in cognizance rate by employing a nearly optimal value. Furthermore, they reveal that the randomized scheme is robust to the fallacy that the reader believes or guesses a wrong number of neighboring tags.

선분 세그먼트 기반 Randomized Hough Transform (Line Segment Based Randomized Hough Transform)

  • 한광수;한영준;한헌수
    • 전자공학회논문지SC
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    • 제44권6호
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    • pp.11-20
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    • 2007
  • 기존 Hough transform을 이용한 타원 검출의 수행 속도와 개수의 추정을 개선하기 위해 본 논문에서는 선분 세그먼트 기반 Randomized Hough Transform (RHT)을 제안한다. 제안하는 방법은 에지 영상을 선분 세그먼트 단위로 분할한 후 임의의 선분 세그먼트 쌍을 RHT를 이용해서 타원을 추정하여 병합여부를 판단한다. 이와 같이 선분 세그먼트 단위로 RHT를 적용하면 적은 반복수행으로 타원을 추정할 수 있으며 복잡한 에지 영상에서도 보다 정확한 타원의 개수를 추정할 수 있다. 제안된 방법의 효율성은 계산속도 및 타원검출의 정확도로 평가하였으며 다양한 입력영상에 대한 실험을 통해 입증하였다.

고혈압 환자를 대상으로 한 기공운동 임상연구 방법론 고찰 (Review of Clinical Trials Using Qigong Exercise on Patients with Hypertension)

  • 정희정;박지은;류연;최선미
    • Korean Journal of Acupuncture
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    • 제28권3호
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    • pp.177-186
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    • 2011
  • Objectives : The aim of this study is to review clinical trials using Qigong exercise on patients with hypertension and to assess their methodology and results. Methods : Electronic literature searches for clinical trials (randomized trial, non-randomized trial, before-after study) of Qigong exercise were performed in 21 electronic databases (5 international databases and 16 Korean databases). English, Korean or Chinese articles were included. Laboratory or animal studies were excluded. Results : A total of 11 studies met the inclusion criteria. Five randomized controlled trials, Four non-randomized trials and two before-after studies were included. Seven studies used self-developed Qigong exercise. Two studies used Guolin Qigong exercise and two studies used Qigong exercise with an anti-hypertension drug. Of the nine randomized trials or non-randomized trials, four studies used an anti-hypertension drug control and three studies used waiting list controls. Compared to baseline, a change in blood pressure after the Qigong exercise treatment was significant in all studies. However, the results effect of blood pressure between Qigong exercise and controlled trials were not consistent. Conclusions : There are low-quality clinical trials of Qigong exercise for hypertension. To evaluate the effects of Qigong exercise, more rigorous trials are warranted.

ILL-VERSUS WELL-POSED SINGULAR LINEAR SYSTEMS: SCOPE OF RANDOMIZED ALGORITHMS

  • Sen, S.K.;Agarwal, Ravi P.;Shaykhian, Gholam Ali
    • Journal of applied mathematics & informatics
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    • 제27권3_4호
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    • pp.621-638
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    • 2009
  • The linear system Ax = b will have (i) no solution, (ii) only one non-trivial (trivial) solution, or (iii) infinity of solutions. Our focus will be on cases (ii) and (iii). The mathematical models of many real-world problems give rise to (a) ill-conditioned linear systems, (b) singular linear systems (A is singular with all its linearly independent rows are sufficiently linearly independent), or (c) ill-conditioned singular linear systems (A is singular with some or all of its strictly linearly independent rows are near-linearly dependent). This article highlights the scope and need of a randomized algorithm for ill-conditioned/singular systems when a reasonably narrow domain of a solution vector is specified. Further, it stresses that with the increasing computing power, the importance of randomized algorithms is also increasing. It also points out that, for many optimization linear/nonlinear problems, randomized algorithms are increasingly dominating the deterministic approaches and, for some problems such as the traveling salesman problem, randomized algorithms are the only alternatives.

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