• 제목/요약/키워드: fast screening

검색결과 131건 처리시간 0.032초

Fast Screening of Harmful Disinfectants in Household Products via Low-Temperature Plasma Ionization-Mass Spectrometry

  • Lee, Hyoung Jun;Kweon, Gi Ryang;Yim, Yong-Hyeon
    • Mass Spectrometry Letters
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    • 제8권2호
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    • pp.44-47
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    • 2017
  • Isothiazolinone derivatives are widely used in consumer products as disinfectants or preservatives, but there are growing concerns about their impact on human health. Therefore, rapid screening of these biocides is very important for proper control and regulation of potentially hazardous substances. To this end, low-temperature plasma (LTP) ionization mass spectrometry (MS) was investigated to demonstrate its potential for direct and selective analysis of isothiazolinones from sprayed aerosol samples. Benzisothiazolinone (BIT) was clearly identified from a commercial fabric deodorant using LTP ionization MS and MS/MS. LTP allowed selective ionization of BIT directly from the simply sprayed aerosol sample and illustrated its potential for fast screening without sample pre-treatments. Selective nature of LTP ionization, on the other hands, implicates use of LTP ionization MS as a general screening method for specific groups of hazardous chemicals in commercial products.

A Fast Contingency Screening Algorithm for On-line Transient Security Assessment Based on Stability Index

  • Nam, Hae-Kon;Kim, Yong-Hak;Song, Sung-Geun;Kim, Yong-Gu
    • KIEE International Transactions on Power Engineering
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    • 제2A권4호
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    • pp.131-135
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    • 2002
  • This paper describes a new ultra-fast contingency screening algorithm for on-line TSA without time simulation. All machines are represented in a classical model and the stability index is defined as the ratio between acceleration power during a fault and deceleration power after clearing the fault. Critical clustering of machines is done based on the stability index, and the power-angle curve of the critical machines is drawn assuming that the angles of the critical machines increase uniformly, while those of the non-critical ones remain constant. Finally, the critical clearing time (CCT) is computed using the power-angle curve. The proposed algorithm is tested on the KEPCO system comprised of 900-bus and 230-machines. The CCT values computed with the screening algorithm are in good agreement with those computed using the detailed model and the SIME method. The computation time for screening about 270 contingencies is 17 seconds with 1.2 GHz PC.

온라인 과도안정도 판정을 위한 상정사고 고속 스크리닝 알고리즘 개발 (A Fast Screening Algorithm for On-Line Transient Stability Assessment)

  • 이종석;양정대;이병준;권세혁;남해곤;추진부;이경극;윤상현;박병철
    • 대한전기학회논문지:전력기술부문A
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    • 제50권5호
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    • pp.225-233
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    • 2001
  • SIME(SIngle Machine Equivalent) method has been recognized as a useful tool to determine transient stability of power systems. In this paper, SIME method is used to develop the KEPCO transient stability assessment (TSA) tool. A new screening algorithm that can be implemented in SIME method is proposed. The salient feature of the proposed screening algorithm is as follows. First, critical generators are identified by a new index in the early stage of the time domain simulation. Thus, computational time required to find OMIB(One Machine Infinite Bus) can be reduced significantly. Second, clustering critical machines can be performed even in very stable cases. It enables to be avoid extra calculation of time trajectory that is needed in SIME for classifying the stable cases. Finally, using power-angle trajectory and subdividing contingency classification have improved the screening capability. This algorithm is applied to the fast TSA of the KEPCO system.

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전압안전도를 고려한 상정사고 스크린닝에 관한 연구 (A Study of Contingency Screening Method Considering Voltage Security)

  • 송길영;김영한;최상규
    • 대한전기학회논문지
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    • 제39권2호
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    • pp.133-141
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    • 1990
  • In the operation of an electric power system, the voltage security of the system has acquired more significant importance after the occurrence of large system black-outs caused by voltage collapse several times. This paper describes a fast contingency screening method concerning voltage security. The method defines a voltage-sensitive buses where significant voltage changes would occur as a result of the contingency to reduce the number of bus voltages to be solved for continngency screening. This method is based on the observation that it is not necessary to solve the entire network in most contingency cases because boltage changes actually occur around the contingency. The P-Q decoupled linearized model and the fast error correction method are also adopted in the method to define voltage-sensitive buses and to calculate voltage magnitude on the selected voltage-sensitive buses fastly and reliably. The method suggested in this papaer has been tested in IEEE 30-bus model system and KEPCO 130-bus actual system and its effectiveness for practical use has also been confirmed.

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Fast High-throughput Screening of the H1N1 Virus by Parallel Detection with Multi-channel Microchip Electrophoresis

  • Zhang, Peng;Park, Guenyoung;Kang, Seong Ho
    • Bulletin of the Korean Chemical Society
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    • 제35권4호
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    • pp.1082-1086
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    • 2014
  • A multi-channel microchip electrophoresis (MCME) method with parallel laser-induced fluorescence (LIF) detection was developed for rapid screening of H1N1 virus. The hemagglutinin (HA) and nucleocapsid protein (NP) gene of H1N1 virus were amplified using polymerase chain reaction (PCR). The amplified PCR products of the H1N1 virus DNA (HA, 116 bp and NP, 195 bp) were simultaneously detected within 25 s in three parallel channels using an expanded laser beam and a charge-coupled device camera. The parallel separations were demonstrated using a sieving gel matrix of 0.3% poly(ethylene oxide) ($M_r$ = 8,000,000) in $1{\times}$ TBE buffer (pH 8.4) with a programmed step electric field strength (PSEFS). The method was ~20 times faster than conventional slab gel electrophoresis, without any loss of resolving power or reproducibility. The proposed MCME/PSEFS assay technique provides a simple and accurate method for fast high-throughput screening of infectious virus DNA molecules under 400 bp.

과도 안정도 해석 프로그램을 위한 상정사고 스크리닝 모듈 개발 (Development of Contingency Screening Module for Transient Stability Analysis Program)

  • 황정희;김천회;장길수;이병준;권세혁;조윤성;김태균
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.335-337
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    • 2005
  • The purpose of this work is to explain techniques achieved while developing a transient stability program which is suitable to Korean power system, and to add a module for contingency screening. It concentrates on the development of Contingency Screening Module. In this thesis, a fast contingency screening algorithm SIME(Single Machin Equivalent), which is one of the Hybrid methods for the transient stability assessment is used to develop the contingency screening module. The proposed module is applied to a KEPCO system, and simulation results obtained from the program are compared to those of commercial programs.

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대규모계통 과도 안정도 평가를 위한 상정사고 고속스크리닝 알고리즘 (A Fast Screening Algorithm for Transient Stability Assessment of Large Power Systems)

  • 양정대;이종석;이병준;권세혁;이경극
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 A
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    • pp.69-71
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    • 2000
  • Transient Stability of a power systems is its ability to maintain synchronous operation of machine when subjected to a large disturbance. This paper presents a new methodology for speed-up transient stability evaluation in SIME. SIME is a hybrid direct method including time simulation to enhance flexibility. It is difficult to apply the classical SIME to stable cases. To solve this problem, we propose the improved SIME, applicable to stable cases as well as unstable cases. For more fast screening, a reduced order equivalent generator is used in the first step process

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복부둔상 환자의 혈복강 진단에 있어 FAST의 유용성에 대한 고찰 (Usefulness of FAST for Evaluation of Blunt Abdominal Trauma Patients)

  • 추용식;김옥준;최성욱;이정한
    • Journal of Trauma and Injury
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    • 제19권2호
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    • pp.135-142
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    • 2006
  • Purpose: We planned to determine the diagnostic capability of focused assessment with sonography for trauma (FAST) in cases of blunt abdominal injury (BAI). Methods: A retrospective analysis of FAST sheets was performed from April 2002 to December 2004. During the study period, 135 BAI patients were evaluated with FAST at the Emergency Department of Bundang CHA Hospital. Of this group, twenty-eight patients were excluded, leaving 107 patients for analysis. Abdomen CT (computerized tomography) or exploratory laparotomy confirmed the presence of hemoperitoneum. At the secondary survey, patients underwent a three-view FAST examination (LogicQ; General Electric, Waukesha, USA) by an emergency physician, followed within 2 hours by an abdomen CT or exploratory laparotomy. The FAST examination was considered positive if it demonstrated evidence of free intra-abdominal fluid. Results: There were 45 true-positive FAST examination, 57 true-negatives, 1 false-positive, and 4 false negatives (sensitivity 91.8%, specificity 98.3%, positive predictive value 97.8%, negative predictive value 93.4%). The area under the ROC curve was 0.951 for the FAST examination. Conclusion: FAST is a highly reliable method for screening patients suspected of having BAI for the presence or absence of hemoperitoneum.

Development of Fast Screening Method for Crop Protection Agents in Tobacco by Stir Bar Sorptive Extraction and Thermal Desorption coupled to GC/MS

  • Min, Hye-Jeong;Lee, Jeong-Min;Shin, Han-Jae;Lee, Moon-Yong;Jang, Gi-Chul
    • 한국연초학회지
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    • 제36권1호
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    • pp.26-33
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    • 2014
  • Simultaneous determination of crop protection agents(CPAs) in food are done with multi-residue methods, which are composed of sample clean-up, concentration, chromatographic separation and detection. Stir Bar Sorptive Extraction(SBSE) technique is used for sample preparation of various analytes in several fields. The aim of this study was to develop a sensitive and fast method based on SBSE followed by thermal desorption - gas chromatography - mass spectrometry(TD - GC/MS) to determine CPAs in tobacco sample. For the analysis of tobacco sample prior to the SBSE method, solvent extraction or ultrasound-assisted solvent extraction was performed. methanol was used as the extraction solvent. The extract was then diluted with water. Finally, the sample was subjected to SBSE. A method for fast screening of crop protection agents in tobacco using SBSE-TD - GC/MS has been developed. About 17 CPAs including organochlorine, organophosphorous and others were identified and quantified. This method showed good linearity and high sensitivity for most of the target CPAs. The method was applied to the determination of CPAs at ng/mL levels in tobacco sample. This method is simple, rapid and may be applied in detection of other components.

In silico High-Throughput Screening by Hierarchical Chemical DB Search by 3D Pharmacophore Model

  • Shin, Jae-Min
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.181-182
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    • 2002
  • Recentadvancesin '-omics ' technologies enable us to discover more diverse disease- relevant target proteins, which encourages us to find out more target-specific novel lead compounds as new drug candidates. Therefore, high-throughput screening (HTS) becomes an essential tool in this area. Among many HTS tools, in silico HTS is a very fast and cost-effective tool to try to derive a new lead compound for any new targets, especially when the target protein structures are known or readily modeled. (omitted)

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