• 제목/요약/키워드: Detector Optimization

검색결과 123건 처리시간 0.03초

교통신호의 자동최적제어에 관한 연구 (Automatic Optimum Control of the Traffic Signal Lights)

  • 양흥석;김호윤
    • 전기의세계
    • /
    • 제20권4호
    • /
    • pp.12-16
    • /
    • 1971
  • The electrical detector and computer systems for traffic flow and speed measurement are demonstrated in this paper. For the best traffic control optimization, linear and non-linear equations in the transition state are dealing with the perturbation of the linear car-following. In the conclusions, we construct a realizable system for the central automatic traffic control with a computer. Furthermore, fixed periodic switching system by manual with the automatic traffic control system is recommended for emergency perturbation.

  • PDF

Optimization of a fiber optic probe for non-invasive blood glucose monitoring

  • Kang, Na-Roo;Baek, Ju-Hyun;Woo, Young-Ah;Lee, Hyun-Chul;Kim, Hyo-Jin
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
    • /
    • pp.407.3-408
    • /
    • 2002
  • A portable near infrared (NIR) system which was newly integrated by our lab has been used to develop a non-invasive blood glucose monitoring. The portable NIR system includes a tungsten halogen lamp, a photo diode array type-InGaAs detector, and specialized reflectance fiber optic probes. The shape of probes is composed of two parts. one for illumination into sample and the other for receiving the radiation from sample. Three kinds of probes with different distance between illumination and receiving part. such as 0.03. 0.1. and 0.5mm, were investigated for optimization. (omitted)

  • PDF

MAP Estimation을 이용한 QRS Detection (QRS detection based on maximum a-posteriori estimation)

  • 정희교;신건수;이명호
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
    • /
    • pp.709-712
    • /
    • 1987
  • In this paper, a mathematical model for the purpose of QRS detection is considered in the case of the occurrence of nonoverlapping pulse-shaped waveforms corrupted with white noise. The number of waveforms, the arrival times, amplitudes, and widths of QRS complexes are regarded as random variables. The joint MAP estimation of all the unknown quantities consists of linear filtering followed by an optimization procedure. Because of time-consuming, the optimization procedure is modified so that a threshold test is obtained. The model formulation with nonoverlapping waveforms leads to a standard procedure covering a segment before as well as after an accepted event. Adaptivity of the detector is gained by utilizing past signal properties in determining threshold for QRS detection.

  • PDF

Optimization of Headspace Analysis of Volatile Compounds from Oxidized Fish Oil

  • Shin, Eui-Cheol;Jang, Hae-Jin;Lee, Hyung-Il;An, Hae-Jung;Lee, Yang-Bong
    • Preventive Nutrition and Food Science
    • /
    • 제8권4호
    • /
    • pp.315-320
    • /
    • 2003
  • Headspace volatile compounds of oxidized fish oil were analyzed by the combination of hexane solvent or solid phase microextraction, gas chromatography and mass selective detector. The optimum condition of headspace analysis by hexane trapping was 23 min absorption time, 96$^{\circ}C$ sample temperature and 20 mL/min air flow rate. The numbers of volatile compounds identified by solvent trapping and SPME were 35 and 14, respectively. Groups having the largest amount and many kinds were hydrocarbons and aldehydes, respectively. The numbers of aldehydes were 15 and 6 for solvent trap and SPME, respectively. These basic data could be used as indicators for the quality changes of fish oil.

Optimization of Diffractive Optical Elements by Genetic Algorithm

  • Yoon, Jin-Seon;Kim, Nam
    • Journal of the Optical Society of Korea
    • /
    • 제4권1호
    • /
    • pp.30-36
    • /
    • 2000
  • In this paper, a method based on the Genetic Algorithm(GA) for phase optimization is proposed. The programmable hybrid optical interconnection system implemented by the spatial light modula-tor is tested for a near-real-time optical processing. Designed diffractive grating has a 74.7[%] high diffraction efficiency and a $1.73 {\times}10^{-1}$ uniformity quantitatively. The dependence of characteris-tics on several parameters in the grating design are analyzed. Also, as a result of the geometrical transformation to obtain quantitative data for $3 {\times} 3$ spot beams, an objective optical experiment using CCD array detector produces the mean of beam intensity as a gray level of 202, the maximum value is 225, the minimum value is 186, and uniformity is quantitatively $1.93 {\times} 10^{-1}$, similar to the simulation result.

An Optimal Design Procedure based on the Safety Integrity Level for Safety-related Systems

  • Kim, Sung Kyu;Kim, Yong Soo
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제12권12호
    • /
    • pp.6079-6097
    • /
    • 2018
  • Safety-related systems (SRSs) has widely used in shipbuilding and power generation to prevent fatal accidents and to protect life and property. Thus, SRS performance is a high priority. The safety integrity level (SIL) is the relative performance level of an SRS with regard to its ability to operate reliably in a safe manner. In this article, we proposed an optimal design procedure to achieve the targeted SIL of SRSs. In addition, a more efficient failure mode and effects diagnostic analysis (FMEDA) process and optimization model were developed to improve cost efficiency. Based on previous IEC 61508 diagnostic analyses that revealed unnecessary costs associated with excessive reliability, the new approach consists of two phases: (i) SIL evaluation by FMEDA, and (ii) solution optimization for achieving the target SIL with minimal cost using integer-programming models. The proposed procedure meets the required safety level and minimizes system costs. A case study involving a gas-detection SRS was conducted to demonstrate the effectiveness of the new procedure.

방사선 영상 디텍터에서 필터링된 이득지도를 사용한 불균일 이득 잡음의 보정 (Nonuniform Gain Correction Based on the Filtered Gain Map in Radiography Image Detectors)

  • 김동식
    • 전자공학회논문지
    • /
    • 제53권4호
    • /
    • pp.97-105
    • /
    • 2016
  • 방사선 영상 디텍터는 x선 광자로부터 생성된 전하를 수집하여 다수의 전하증폭기 회로를 사용하여 전압 신호로 바꾼 뒤 이를 디지털 신호로 바꾸어 디지털 영상을 생성한다. 이때 다수로 사용한 회로의 불균일한 특성으로 인하여 이득의 불균일이라는 고정형태잡음이 발생한다. 이를 제거하기 위하여 이득지도를 사용하는 이득 보정 알고리듬이 일반적으로 사용되는데, 이득지도 설계 시에 광자 잡음이 이득지도에 남게 되고 이 잡음은 이득 보정된 영상을 오염시킨다. 본 논문에서는 이러한 남아있는 잡음을 필터를 사용하여 제거하는 실험을 하였으며, 효율적으로 잡음을 제거하기위한 필터를 최적화하는 알고리듬을 제안하였다. 실제 디텍터로 획득한 영상에 대하여 실험을 수행하여, 단순한 필터로 제거하기 힘든, 고정형태잡음의 크기가 상대적으로 큰 경우에도, 필터 최적화 알고리듬을 사용하여 효율적으로 잡음 제거에 대한 성능을 개선시킬 수 있음을 보였다.

비정질 셀레늄을 이용한 평판 Digital X선 검출기 개발 (Development of flat panel digital x-ray detectorusing a-Se)

  • 박지군;최장용;강상식;차병열;장기원;최준영;남상희
    • 대한디지털의료영상학회논문지
    • /
    • 제6권1호
    • /
    • pp.24-30
    • /
    • 2003
  • 평판 digital x-선 검출기는 차세대 x-ray system으로 최근 연구와 개발이 활발하게 진행되고 있는 system이다. 본 연구는 환자의 피폭 및 작업 종사자의 피폭을 최소화 할 수 있고 의료장비의 디지털화에 발맞추어 PACS 등에 사용 가능한 a-Se을 이용한 직접방식의 digital x-선 검출기 구현에 관한 것이다. Prototype digital x-선 검출기는 TFT층과 a-Se층으로 이루어져 있다. Digital x-선 검출기센서 증착과 정의 최적화 수행 결과를 참고문헌1)-4)과 비교했을 때 매우 유사함을 확인하였다. 제작된 검출기의 pixel pitch는 $139{\mu}m$였고, fill factor는 86%, 전체 검출기의 검출면적은 14"${\times}$8.5"였다. Digital 영상의 해상력을 고려하기 위해 손과 test 패턴영상을 얻었고, 58%, 3.0lp/mm의 높은 MTF를 얻을 수가 있었다. 이러한 결과로 a-Se 기반의 Digital X선 검출기가 구현되었으며 본 연구결과를 토대로 향후 digital X선 검출기 개발기술의 발전과 성능향상을 가져올 것으로 기대된다.

  • PDF

자기 벡터 포텐셜 해석을 이용한 금속 검출기 코일 헤드의 검출 성능 최적화 (Optimization of the Coil Head of Metal Detectors Using a Magnetic Vector Potential Approach)

  • 오준석;은창수
    • 전자공학회논문지SC
    • /
    • 제46권5호
    • /
    • pp.38-43
    • /
    • 2009
  • 본 논문에서는 자기 벡터 포텐셜 해석을 통해 3-코일 구조를 갖는 금속 검출기 헤드가 수신 코일에 미치는 유도 전압을 구하고, 금속 물체의 특성이 송신 코일의 임피던스에 미치는 영향을 유도하였다. 이러한 해석을 통하여 최적의 검출 성능을 위한 송신 코일과 수신 코일 간의 거리를 구하였고, 최대 유도 전압을 출력하는 금속의 위치를 유도하였다. 또한 기존의 수식과 비교하여 본 논문의 자기 벡터 포텐셜 해석에 대한 타당성을 입증하였다.

PIB법을 이용한 대면적 $HgI_2$ 검출기의 I-V 특성평가 (I-V Measurements of large area $HgI_2$ X-ray detector produced by PIB method)

  • 김경진;박지군;강상식;차병열;조성호;신정욱;문치웅;남상희
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
    • /
    • pp.254-255
    • /
    • 2005
  • In this paper, we investigated electrical characteristics of the X-ray detector of mercuric iodide (HgI2) film fabricated by PIB(Particle-in-Binder) Method on ITO substrates 17cm$\times$20cm in size with thicknesses ranging from approximately 200${\mu}m$ to 240${\mu}m$. In the present study, using I-V measurements, their electrical properties such as leakage current, X-ray sensitivity, and signal-to-noise ratio (SNR),were investigated. The results of our study can be useful in the future design and optimization of direct active-matrix flat-panel detectors (AMFPD) for various digital X-ray imaging modalities.

  • PDF