• Title/Summary/Keyword: Over-Sampling

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멀티 라인 레이저 비전 센서를 이용한 고속 용접선 추적 기술 (High speed seam tracking using multi-line laser vision sensor)

  • 성기은;이세헌
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.584-587
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    • 2002
  • A vision sensor measure range data using laser light source. This sensor generally use patterned laser which shaped single line. But this vision sensor cannot satisfy new trend which needs laster and more precise processing. The sensor's sampling rate increases as reduced image processing time. However, the sampling rate can not over 30fps, because a camera has mechanical sampling limit. If we use multi line laser pattern, we will measure multi range data in one image. In the case of using same sampling rate camera, number of 2D range data profile in one second is directly proportional to laser line's number. For example, the vision sensor using 5 laser lines can sample 150 profiles per second in best condition.

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Digital 형상의 새로운 Uniform Sampling 방법 (A New Uniform Sampling Method of the Digital Contour)

  • 정영기;이재구;김영일;우동민
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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    • pp.209-212
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    • 1988
  • This paper presents a new uniform sampling method for two-dimensional contour. The proposed method improves the uniformity of contour sampling in terms of the interpolation of the corner points extracted from chain codes. The performance of the proposed method is analyzed through the length estimation and shape recognition of two-dimensional contour. The experimental results show the significant improvement over the conventional method.

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A Modified Single Sampling Plan for the Inspection of Attribute Quality Characteristics

  • Subramani, J.;Balamurali, S.
    • Industrial Engineering and Management Systems
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    • 제15권1호
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    • pp.41-48
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    • 2016
  • In this manuscript, a modified single sampling plan is proposed for the inspection of products in which the nonconforming items can be classified in to two categories namely critical and non-critical; and explained with the help of industrial example. The operating procedure of this plan is also proposed and the performance measures such as the probability of acceptance, average sample number, average total inspection and average out going quality are also derived. The optimal parameters are determined which will have minimum sample size. The efficiency of the proposed plan is also discussed over the conventional single sampling plan. The extensive tables for selecting a modified single sampling plan based on AQL and LQL are provided for both Binomial and Poisson distributions and explained with the help of industrial data.

In-line (α,n) source sampling methodology for monte carlo radiation transport simulations

  • Griesheimer, David P.;Pavlou, Andrew T.;Thompson, Jason T.;Holmes, Jesse C.;Zerkle, Michael L.;Caro, Edmund;Joo, Hansem
    • Nuclear Engineering and Technology
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    • 제49권6호
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    • pp.1199-1210
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    • 2017
  • A new in-line method for sampling neutrons emitted in (${\alpha}$,n) reactions based on alpha particle source information has been developed for continuous-energy Monte Carlo simulations. The new method uses a continuous-slowing-down model coupled with (${\alpha}$,n) cross section data to precompute the expected neutron yield over the alpha particle lifetime. This eliminates the complexity and computational cost associated with explicit charged particle transport. When combined with an integrated alpha particle decay source sampling capability, the proposed method provides an efficient and accurate method for sampling (${\alpha}$,n) neutrons based solely on nuclide inventories in the problem, with no additional user input required. Results from several example calculations show that the proposed method reproduces the (${\alpha}$,n) neutron yields and energy spectra from reference experiments and calculations.

Adaptive kernel method for evaluating structural system reliability

  • Wang, G.S.;Ang, A.H.S.;Lee, J.C.
    • Structural Engineering and Mechanics
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    • 제5권2호
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    • pp.115-126
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    • 1997
  • Importance sampling methods have been developed with the aim of reducing the computational costs inherent in Monte Carlo methods. This study proposes a new algorithm called the adaptive kernel method which combines and modifies some of the concepts from adaptive sampling and the simple kernel method to evaluate the structural reliability of time variant problems. The essence of the resulting algorithm is to select an appropriate starting point from which the importance sampling density can be generated efficiently. Numerical results show that the method is unbiased and substantially increases the efficiency over other methods.

출구조사의 투표소 표집방안 비교 (How to Select Polling Places in Exit Poll?)

  • 조성겸;김지연
    • 한국조사연구학회지:조사연구
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    • 제5권2호
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    • pp.3-30
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    • 2004
  • 출구조사에서 투표소 표집방법으로는 지금까지 판단표집의 일종인 대표구 추출방법과 층화 대표구의 두 가지 방법이 주로 사용되고 있지만 아직 어느 방법이 더 효과적인가에 대해서 체계적인 연구가 이어지지 않았다. 본 연구는 지금까지 논의되어 온 네가지 투표소 추출방법 중에서 어느 방법을 사용할 때 오차가 가장 적을것인지 그리고 어느 정도의 투표소를 추출하는 것이 적절한지에 대해서 분석해 보았다. 17대 총선에서 1위와 2위간의 격차가 8% 이내로 경합을 보인 50개 선거구를 대상으로 투표소 추출방법과 추출규모를 달리했을 때 예측오차가 어떻게 달라지는가를 분석한 결과, 과거 선거결과를 토대로 투표소를 정치성향별로 정렬한 후 체계적으로 추출하는 '종단적 체계적 추출방법'이 지금까지 주로 사용되었던 대표구 혹은 층화후 대표구 방법보다 우수한 것으로 나타났다. 그리고 표집규모는 9개에서 11개 정도의 투표소 추출이 적절한 것으로 나타났다.

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Is Simple Random Sampling Better than Quota Sampling? An Analysis Based on the Sampling Methods of Three Surveys in South Korea

  • Cho, Sung Kyum;Jang, Deok-Hyun;LoCascio, Sarah Prusoff
    • Asian Journal for Public Opinion Research
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    • 제3권4호
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    • pp.156-175
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    • 2016
  • This paper considers whether random sampling always produces more accurate survey results in the case of South Korea. We compare information from the 2010 census to the demographic variables of three public opinion surveys from South Korea: Gallup Korea's Omnibus Survey (Survey A) is conducted every two months by Gallup Korea; the annual Social Survey (Survey B) is conducted by Statistics Korea (KOSTAT); the Korean General Social Survey (KGSS or Survey C) is conducted annually by the Survey Research Center (SRC) at Sungkyunkwan University (SKKU). Survey A uses quota sampling after randomly selecting the neighborhood and initial addresses; Survey B uses random sampling, but allows replacements in some situations; Survey C uses simple random sampling. Data from more than one year was used for each survey. Our analysis suggests that Survey B is the most representative in most respects, and, in some respects, Survey A may be more representative than Survey C. Data from Survey C was the least stable in terms of representativeness by geographical area and age. Single-person households were underrepresented in both Surveys A and C, but the problem was more severe in Survey A. Four-person households and married persons were both over-represented in Survey A. Less educated people were under-represented in both Survey A and Survey C. There were differences in income level between Survey A and Survey C, but income data was not available for Survey B or the census, so it is difficult to ascertain which survey was more representative in this case.

Sub-Sampling 방식의 다중 대역 수신기에서 타이밍 오프셋과 주파수 오프셋 보상 (Compensation of Timing Offset and Frequency Offset in the Multi-Band Receiver with Sub-Sampling Method)

  • 이희규;유흥균
    • 한국전자파학회논문지
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    • 제22권5호
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    • pp.501-509
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    • 2011
  • Software Defined Radio(SDR)에서는 ADC를 안테나 가까이에 위치시키는 것을 목표로 하고 있다. 하지만 실제 RF 대역의 신호를 ADC를 이용해 디지털화 하는 방법은 아직 어렵다. 그래서 RF 대역의 신호를 IF 대역으로 하향 변환 후 샘플링을 하는 방법이 연구되고 있다. 이런 방법의 하나로, Sub-Sampling 방식은 발진기 없이 RF 대역의 신호를 IF로 변환할 수 있는 방법이다. Sub-Sampling 방법을 이용한다면 2개 이상의 밴드를 하향 변환할 수 있지만, RF 필터의 성능으로 인해 하향 변환된 신호간에 간섭이 작용할 수 있어 성능을 저하시킨다. 본 논문에서는 time division multiplexing(TDM) 방식을 이용해 2개 이상의 신호를 시간적으로 분리시킴으로써 RF 필터의 좋지 않은 성능으로 인해 발생할 수 있는 신호간 간섭을 피할 수 있는 방법을 제안한다. 이 방식은 샘플앤홀더에서 두 신호에 대한 시간적 분리와 Sub-Sampling을 동시에 구현함으로써 하드웨어적인 큰 변화 없이 신호를 수신할 수 있다.

농촌노인의 일상생활수행능력과 우울감, 자아존중감 및 사회활동 참여가 생활만족도에 미치는 영향 -경기도 여주를 중심으로- (The Effect of Daily Living Activities, Depression, Self-respect, and Social Activity Participation of the Rural Elderly on Their Life Satisfaction -Centering on Yeoju, Gyeonggi-)

  • 이현심;남희수
    • 농촌지도와개발
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    • 제17권4호
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    • pp.957-984
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    • 2010
  • The aim of this research is to delineate how daily living activities, depression, self-respect, and social activity participation affects the life satisfaction of the rural elderly. The subjects of the research were elderly over-65-year-olds living in Yeoju, Gyeonggido and conducted from November 15 to November 30, 2009. The sampling method was convenience sampling among non-probability sampling, a total of 339 were used as analysis data. The collected data were then put through-frequency analysis, correlation analysis, simple regression analysis, analysis of variance, Kruskal-Wallis, and feasibility verification through SPSS SAS 9.1.3 program. As a result of hypothesis verification, daily living activities have a positive influence over life satisfaction. And the higher the elderly's self-respect, the greater their life satisfaction, and it was verified that depending on social activity participation, there is a difference in their life satisfaction. The purpose of this study is to verify and carry out action plan and ital.

휘발성(揮發性) Warmed-Over Flavor의 연구(硏究)를 위한 변형(變形)된 Direct Sampling GLC법(法) (Modified Direct-Sampling GLC Method to Study Warmed-Over Flavor Related Volatiles)

  • 신승이;이종욱
    • 한국식품과학회지
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    • 제22권5호
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    • pp.562-568
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    • 1990
  • 조리(調理) 육류(肉類)의 WOF와 관련(關聯)된 휘발성(揮發性) 성분(成分)을 분석(分析)하기 위하여 변형(變形)된 Direct GLC 방법(方法)을 이용(利用)하였다. 이 변형(變形)된 방법(方法)은 기존(旣存)의 다른 방법(方法)과는 달리 수분함량(水分含量)이 많은 시료(試料)로부터 휘발성(揮發性) 성분(成分)을 분리(分離)하는데 유용(有用)하였으며, 특히 저분자량(低分子量)의 포화(飽和) $aldehyde\;(C_c-C_{15})$류(類), 불포화(不飽和)$aldehyde(C_5{\sim}C_9)$류(類)의 연구(硏究)에 적절한 것으로 판명(判明)되었다.

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