• Title/Summary/Keyword: multi-sampling

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Experimental Considration of Multi-order Sampling for Digital Beamforming (디지털 빔포밍을 위한 다차 샘플링 방법의 실험적 고찰)

  • 나병윤;정목근
    • Journal of Biomedical Engineering Research
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    • v.19 no.2
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    • pp.105-112
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    • 1998
  • In this paper, several bandwidth sampling methods were compared using experimental result in which contains "multi-order sampling", which was proposed for envelope detections in RF ultrasonic signals. A "Quadrature sampling method" and "Second-order sampling method" were compared with it. The resultant image of second-order sampling method introduces too much error as compared with the result of quadrature sampling. But Multi-order sampling method, specialy 5-th sampling method showed quite good envelope detection property. This means that more economical and quite good performance digital beamforming system can be built by adopting this multi-order sampling method.s multi-order sampling method.

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Experimental consideration of multi -order sampling or digital beamforming (디지털 빔포밍을 위한 다차 샘플링 방법의 실험적 고찰)

  • Na, B.Y.;Jeong, M.K.;Ahn, Y.B.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.563-566
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    • 1997
  • In this paper, several bandwidth sampling methods were compared in which contains "multi-order sampling", which was proposed or envelope detections in RF ultrasonic signals by a computer simulation and on experiment quadrature sampling method. The second-order sampling method were compared with it. As a conclusion, a multi-order sampling method, especially 5th order sampling method showed quite good envelope detection property. This means that more economical and quite good performance digital beamforming system can be built by adopting this new bandwidth sampling method.

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A VSR $\bar{X}$ Chart with Multi-state VSS and 2-state VSI Scheme

  • Lee, Jae-Heon;Park, Chang-Soon
    • Journal of Korean Society for Quality Management
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    • v.32 no.4
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    • pp.252-264
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    • 2004
  • Variable sampling Interval (VSI) control charts vary the sampling interval according to value of the control statistic while the sample size is fixed. It is known that control charts with 2-state VSI scheme, which uses only two sampling intervals, give good statistical properties. Variable sample size (VSS) control charts vary the sample size according to value of the control statistic while the sampling interval is fixed. In the VSS scheme no optimal results are known for the number of sample sizes. It is also known that the variable sampling rate (VSR) $\bar{X}$ control chart with 2-state VSS and 2-state VSI scheme leads to large improvements In performance over the fixed sampling rate (FSR) $\bar{X}$ chart, but the optimal number of states for sample size Is not known. In this paper, the VSR Χ charts with multi-state VSS and 2-state VSI scheme are designed and compared to 2-state VSS and 2-state VSI scheme. The multi-state VSS scheme is considered to, achieve an additional improvement by switching from the 2-state VSS scheme. On the other hand, the multi-state VSI scheme is not considered because the 2-state scheme is known to be optimal. The 3-state VSS scheme improves substantially the sensitivity of the $\bar{X}$ chart especially for small and moderate mean shifts.

Design of Sampling Inspections and Service Capacities for Multi-Products (복수제품의 품질검사 및 서비스시스템의 설계)

  • 김성철
    • Journal of the Korean Operations Research and Management Science Society
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    • v.28 no.3
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    • pp.49-60
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    • 2003
  • In this paper, we study the joint design of sampling inspections and service capacities for multi-products. Products of different defect rates which are either deterministic or random variables are supplied in batches after sampling inspection and rework. When supplied, all defective products that have not been inspected in batches are uncovered through total inspection and returned to service. We identify the optimal inspection policies and service capacities for multi-products reflecting the relationships between inspection rework costs and service provision costs. We also develope a marginal allocation algorithm for the optimal allocation of the limited total service capacity to products as well as inspection quantities.

Precision servo control of a computer hard disk (컴퓨터 하드 디스크의 정밀 서보 제어)

  • 전도영
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.286-289
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    • 1996
  • Two servo control algorithms are suggested to reduce the tracking error of a computer hard disk drive. One is the repetitive control to reduce the repeatable tracking error which is not explicitly taken into account in the design of a conventional controller. This algorithm was successfully applied to a commercial disk using a fixed point DSP. The other is the multi-rate sampling control which generates the control output between each sampling times since the sampling time of hard disk drives is limited. These algorithms were shown effectively to reduce tracking errors.

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Modified Multi-Level Skip-Lot Sampling Plans

  • Cho, Gyo-Young;Choi, Eun-Jung
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.4
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    • pp.915-927
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    • 2003
  • This paper is the generalization of the modified two-level skip-lot sampling plan(MTSkSP1) to n-level. The general formulas of the operating characteristic(OC) function, average sample number(ASN) and average outgoing quality(AOQ) for the plan are derived using Markov chain properties. The operating characteristic curves, average sample numbers and average outgoing qualities of a reference plan, modified two-level, three-level and five-level skip-lot sampling plans are compared.

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Operating Characteristic Properties of Two Types of Multi-Level Skip-Lot Sampling Plans

  • Byoung-Chul Choi
    • Communications for Statistical Applications and Methods
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    • v.2 no.2
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    • pp.358-365
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    • 1995
  • This paper presents another system of multi-level skip-lot sampling plan, which can directly retum to normal inspection from any skpping inspection level when a sudden shift for the worse in the process mean occurs. All the other properties of the proposed sampling plan are similar to those of the Choi's(1993) plan. The formula of the poerating characteristic function for the proposed n-level skip-lot sampling plan is derived. Sone poerating characteristic properties for the proposed plan are graphically compared with those of the Choi's plan.

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Development of multi-line laser vision sensor and welding application (멀티 라인 레이저 비전 센서를 이용한 고속 3차원 계측 및 모델링에 관한 연구)

  • 성기은;이세헌
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.169-172
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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 feeds foster 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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High speed seam tracking system using vision sensor with multi-line laser (다중 레이저 선을 이용한 비전 센서를 통한 고속 용접선 추적 시스템)

  • 성기은;이세헌
    • Proceedings of the KWS Conference
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    • 2002.05a
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    • pp.49-52
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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 faster 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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High speed seam tracking using multi-line laser vision sensor (멀티 라인 레이저 비전 센서를 이용한 고속 용접선 추적 기술)

  • 성기은;이세헌
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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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.

  • PDF