• Title/Summary/Keyword: Bias detection

Search Result 244, Processing Time 0.026 seconds

Two-Stage Estimator Design Using Stable Recursive FIR Filter and Smoother

  • Kim, Jong-Ju;Kim, Jae-Hun;Lyou, Joon
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.2532-2537
    • /
    • 2005
  • FIR(Finite Impulse Response) filter is well known to be ideal for the finite time state-space model, but it requires much computation due to its inherent non-recursive structure especially when the measurement interval grows to a large extent. And often a fixed-lag smoother based on the finite time interval is needed to monitor the soundness of the system model and the measurement model, but the computation burden of FIR-type smoother imposes much restriction of its usage for real-time application. Conventional recursive forms of FIR estimator[1]-[4] could not be used for real time applications, since they are numerically unstable in their recursive equations. To cope with this problem, we suggest a stable recursive form FIR estimator(SRFIR) and its usefulness is demonstrated for designing the real-time fixed-lag smoother on the finite time window through an example of detection of rate bias in the anti-aircraft gun fire control system.

  • PDF

Syndromic Surveillances based on the Emergency Department (응급실 증후군 감시체계의 운영 현황과 활성화 방안)

  • Cho, Joon-Pil;Min, Young-Gi;Choi, Sang-Cheon
    • Journal of Preventive Medicine and Public Health
    • /
    • v.41 no.4
    • /
    • pp.219-224
    • /
    • 2008
  • Due to heightened concerns regarding possible bioterrorist attacks, the Korea Center for Disease Control and Prevention introduced syndromic surveillance systems, which have been run by emergency departments in hospitals throughout Korea since 2002. These systems are designed to identify illness clusters before diagnoses are confirmed and reported to public health agencies, to mobilize a rapid response, and thereby to reduce morbidity and mortality. The Korea Center for Disease Control and Prevention performed drop-in syndromic surveillance successfully during the World Cup Football Games in 2002, the Universiad games in 2004, and the Asian Pacific Economic Cooperation meeting in 2005. In addition, sustainable syndromic surveillance system involving the collaborative efforts of 125 sentinel hospitals has been in operation nationwide since 2002. Because active data collection can bias decisions a physician makes, there is a need to generate an automatic and passive data collection system. Therefore, the Korea Center for Disease Control and Prevention plans to establish computerized automatic data collection systems in the near future. These systems will be used not only fur the early detection of bioterrorism but also for more effective public health responses to disease.

Uranium Enrichment Determination Using a New Analysis Code for the U XKα Region: HyperGam-U

  • Kim, Junhyuck;Choi, Hee-Dong;Park, Jongho
    • Nuclear Engineering and Technology
    • /
    • v.48 no.3
    • /
    • pp.778-784
    • /
    • 2016
  • HyperGam-U was recently developed to determine uranium enrichment based on ${\gamma}$- and X-ray spectroscopy analysis. The $XK_{\alpha}$ region of the uranium spectrum contains 13 peaks for $^{235}U$ and $^{238}U$ and is used mainly for analysis. To describe the X-ray peaks, a Lorentzian broadened shape function was used, and methods were developed to reduce the number of fitting parameters for decomposing the strongly overlapping peaks using channel-energy, energy-width, and energy-efficiency calibration functions. For validation, eight certified reference material uranium samples covering uranium enrichments from 1% to 99% were measured using a high-resolution planar high-purity germanium detector and analyzed using the HyperGam-U code. When corrections for the attenuation and true coincidence summing were performed for the detection geometry in this experiment, the goodness of fit was improved by a few percent. The enrichment bias in this study did not exceed 2% compared with the certified values for all measured samples.

Dielectric Relaxation Properties of DMPC Organic Thin Films for Nanotechnology (나노기술을 위한 DMPC 유기박막의 유전완화특성)

  • Chol, Young-Il;Cho, Su-Young
    • 전자공학회논문지 IE
    • /
    • v.49 no.1
    • /
    • pp.7-11
    • /
    • 2012
  • In this paper, evaluation of physical properties about dielectric relaxation phenomena by the detection of the surface pressures and displacements current on the monolayer films of phospolipid monomolecular DMPC using pressure stimulus. As a result, It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area. When electric bias is applied across the manufactured MIM device by the deposition condition of phospolipid monomolecular, it is found that be characteristic of insulation generated it wasn't breakdown when the higher electric field to impress by increase of deposition layers.

Development of the 120kV/70A High Voltage Switching Circuit with MOSFETs Operated by Simple Gate Drive Unit (120kV/70A MOSFETs Switch의 구동회로 개발)

  • Song In Ho;Shin H. S.;Choi C. H.
    • Proceedings of the KIPE Conference
    • /
    • 2002.07a
    • /
    • pp.707-710
    • /
    • 2002
  • A 120kV/70A high voltage switch has been installed at Korea Atomic Energy Research Institute in Taejon to supply power with Korea Superconducting Tokamak Advanced Research (KSTAR) Neutral Beam Injection (NBI) system. NBI system requires fast cutoff of the power supply voltage for protection of the grid when arc detected and fast turn-on the voltage for sustaining the beam current. Therefore the high voltage switch and arc current detection circuit are important part of the NBI power supply and there are much need for high voltage solid state switches in NBI system and a broad area of applications. This switch consisted of 100 series connected MOSFETs and adopted the proposed simple and reliable gate drive circuit without bias supply, Various results taken during the commissioning phase with a 100kW resistive load and NBI source are shown. This paper presents the detailed design of 120kV/70A high voltage MOSFETs switch and simple gate drive circuit. Problems with the high voltage switch and gate driver and solutions are also presented.

  • PDF

Predictability for Heavy Rainfall over the Korean Peninsula during the Summer using TIGGE Model (TIGGE 모델을 이용한 한반도 여름철 집중호우 예측 활용에 관한 연구)

  • Hwang, Yoon-Jeong;Kim, Yeon-Hee;Chung, Kwan-Young;Chang, Dong-Eon
    • Atmosphere
    • /
    • v.22 no.3
    • /
    • pp.287-298
    • /
    • 2012
  • The predictability of heavy precipitation over the Korean Peninsula is studied using THORPEX Interactive Grand Global Ensemble (TIGGE) data. The performance of the six ensemble models is compared through the inconsistency (or jumpiness) and Root Mean Square Error (RMSE) for MSLP, T850 and H500. Grand Ensemble (GE) of the three best ensemble models (ECMWF, UKMO and CMA) with equal weight and without bias correction is consisted. The jumpiness calculated in this study indicates that the GE is more consistent than each single ensemble model. Brier Score (BS) of precipitation also shows that the GE outperforms. The GE is used for a case study of a heavy rainfall event in Korean Peninsula on 9 July 2009. The probability forecast of precipitation using 90 members of the GE and the percentage of 90 members exceeding 90 percentile in climatological Probability Density Function (PDF) of observed precipitation are calculated. As the GE is excellent in possibility of potential detection of heavy rainfall, GE is more skillful than the single ensemble model and can lead to a heavy rainfall warning in medium-range. If the performance of each single ensemble model is also improved, GE can provide better performance.

Sensitivity Alterable Biosensor Based on Gated Lateral BJT for CRP Detection

  • Yuan, Heng;Kang, Byoung-Ho;Lee, Jae-Sung;Jeong, Hyun-Min;Yeom, Se-Hyuk;Kim, Kyu-Jin;Kwon, Dae-Hyuk;Kang, Shin-Won
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.13 no.1
    • /
    • pp.1-7
    • /
    • 2013
  • In this paper, a biosensor based on a gated lateral bipolar junction transistor (BJT) is proposed. The gated lateral BJT can function as both a metal-oxide-semiconductor field-effect transistor (MOSFET) and a BJT. By using the self-assembled monolayer (SAM) method, the C-reactive protein antibodies were immobilized on the floating gate of the device as the sensing membrane. Through the experiments, the characteristics of the biosensor were analyzed in this study. According to the results, it is indicated that the gated lateral BJT device can be successfully applied as a biosensor. Additionally, we found that the sensitivity of the gated lateral BJT can be varied by adjusting the emitter (source) bias.

Disease Prediction Using Ranks of Gene Expressions

  • Kim, Ki-Yeol;Ki, Dong-Hyuk;Chung, Hyun-Cheol;Rha, Sun-Young
    • Genomics & Informatics
    • /
    • v.6 no.3
    • /
    • pp.136-141
    • /
    • 2008
  • A large number of studies have been performed to identify biomarkers that will allow efficient detection and determination of the precise status of a patient’s disease. The use of microarrays to assess biomarker status is expected to improve prediction accuracies, because a whole-genome approach is used. Despite their potential, however, patient samples can differ with respect to biomarker status when analyzed on different platforms, making it more difficult to make accurate predictions, because bias may exist between any two different experimental conditions. Because of this difficulty in experimental standardization of microarray data, it is currently difficult to utilize microarray-based gene sets in the clinic. To address this problem, we propose a method that predicts disease status using gene expression data that are transformed by their ranks, a concept that is easily applied to two datasets that are obtained using different experimental platforms. NCI and colon cancer datasets, which were assessed using both Affymetrix and cDNA microarray platforms, were used for method validation. Our results demonstrate that the proposed method is able to achieve good predictive performance for datasets that are obtained under different experimental conditions.

The characteristic study of hybrid X-ray detector using CdTe and Zns:AgCl phosphor (CdTe 와 ZnS:AgCl phosphor를 이용한 Hybrid형 X선 검출기의 특성연구)

  • Seok, Dae-Woo;Kang, Sang-Sik;Kim, Jin-Young;Park, Ji-Koon;Mun, Chi-Woong;Nam, Sang-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.05c
    • /
    • pp.71-74
    • /
    • 2003
  • Photoconductor for direct detection fiat-panel imager present a great materials challenge, since their requirement include high X-ray absorption, ionization and charge collection, low leakage current and large area deposition, CdTe is practical material. We report studies of detector sensitivity, That is an CdTe with $5{\mu}m$ thickness on glass. That is hybrid layer of depositting ZnS:AgCl phosphor with $100{\mu}m$ on CdTe. The leakage current of hybrid is similar to it of a-Se, but photocurrent is larger than a-Se. Both of them have high spatial resolution, but hybrid has higher sensitivity than a-Se at comparable bias voltage.

  • PDF

Consideration of the analytical bias involved in the detection of total volatile organic compounds (TVOC) (총휘발성유기화합물 (TVOC) 검량의 오차인자에 대한 연구)

  • Kim, K.H.
    • Analytical Science and Technology
    • /
    • v.17 no.6
    • /
    • pp.489-495
    • /
    • 2004
  • In this article, various aspects of errors involved in the measurement of TVOC were examined as part of study to develop the indoor pollution indices. For this purpose, TVOC term was computed by two different calibration approaches, i.e., by assuming all VOC are detected in the same manner as toluene and by summing up as many individual VOC as possible. The results of our study indicate that the common, toluene-based method suffers from errors inherent in the development of such theory. Consequently, it is concluded that more research efforts have to be directed to the improvement of such concept as TVOC.