• Title/Summary/Keyword: Limit of determination

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Remote On-line Determination of the Load Rate Limit of Generation in AGC (AGC 운용에 있어서의 원격 On-line 최대 증감발율 취득 기법)

  • Kwon, Soon-Man;Jeon, Dong-Hoon;Moon, Won-Yong;Kim, Suk-Joo
    • Proceedings of the KIEE Conference
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    • 2000.11a
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    • pp.119-121
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    • 2000
  • The possibility of a remote on-line determination of the maximum load rates that are basically set at generation plants is investigated in automatic generation control (AGC) system. Energy management system (EMS) generates a test input to a remote power plant to get the samples of the generator output. Then from the samples it can be attempted to determine an approximate value of the load rate limit set by the operator. It is shown in computer simulation that in actual power plants the limit can be approximately determined from the input-output characteristics of the plants for a unit-step input.

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Simultaneous Voltammetric Determination of Mefenamic Acid and Paracetamol using Graphene Nanosheets/Nickel Oxide Nanoparticles Modified Carbon Paste Electrode

  • Naeemy, Ali;Gholam-Shahbazi, Rozhina;Mohammadi, Ali
    • Journal of Electrochemical Science and Technology
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    • v.8 no.4
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    • pp.282-293
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    • 2017
  • A new modified carbon paste electrode (CPE) was constructed based on nickel oxide nanoparticles (NiONPs) and graphene nanosheets (Gr) for simultaneous determination of paracetamol (PCM) and mefenamic acid (MFA) in aqueous media and pharmaceutical dosage forms. NiONPs were synthesized via a simple and inexpensive technique and characterized using X-ray diffraction method. Scanning electron microscopy was used for the characterization of the morphology of modified carbon paste electrode (NiONPs/Gr/CPE). Voltammetric studies suggest that the NiONPs and Gr provide a synergistic augmentation that can increase current responses by improvement of electron transfers of these compounds on the NiONPs/Gr/CPE surface. Using cyclic voltammetry, the NiONPs/Gr/CPE showed good sensitivity and selectivity for the determination of PCM and MFA in individually or mixture standard samples in the linear range of $0.1-30{\mu}g\;mL^{-1}$. The resulted limit of detection and limit of quantification were 20 and $60ng\;mL^{-1}$ for PCM, 24 and $72ng\;mL^{-1}$ for MFA, respectively. The analytical performance of the NiONPs/Gr/CPE was evaluated for the determination of PCM and MFA in pharmaceutical dosage forms with satisfactory results.

Development of a Validated Determination of Methylsulfonylmethane in Dietary Supplement by Gas Chromatography (기체크로마토그래피를 이용한 식이보충제에서 메틸설포닐메탄의 검증된 분석법 개발)

  • Park, Sang-Wook;Lee, Wonjae
    • KSBB Journal
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    • v.30 no.4
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    • pp.141-147
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    • 2015
  • The convenient determination of methylsulfonylmethane (MSM) for a commercially available dietary supplement was developed using gas chromatography (GC)-flame ionization detector (FID). Chromatography was performed on a capillary column ($0.32mm\;I.D{\times}30m$, $0.25{\mu}m$) coated with dimethylpolysiloxane using diethylene glycol methyl ether as an internal standard. The performance characteristics of GC were evaluated in terms of selectivity, linearity, precision, accuracy, recovery, limit of detection (LOD) and limit of quantification (LOQ). The calibration curve was highly linear (the coefficient of determination: 0.9979) within the concentration range of $10.0{\sim}800.0{\mu}g/mL$ for MSM. The recoveries for three fortified concentrations were 96.7~97.1%, 96.6~97.3% and 96.8~97.2%, respectively. The LOD and LOQ of the method were $0.29{\mu}g/mL$ and $0.97{\mu}g/mL$, respectively. All obtained results were acceptable according to the guidelines of the Association of Official Analytical Chemists for dietary supplements. Thus, the validated analytical method using the GC-FID system is suitable for the determination of MSM in dietary supplement formulations for quality control.

Validation of an analytical method for cyanide determination in blood, urine, lung, and skin tissues of rats using gas chromatography mass spectrometry (GC-MS)

  • Shin, Min-Chul;Kwon, Young Sang;Kim, Jong-Hwan;Hwang, Kyunghwa;Seo, Jong-Su
    • Analytical Science and Technology
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    • v.32 no.3
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    • pp.88-95
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    • 2019
  • This study was conducted to establish the analytical method for the determination of cyanide in blood, urine, lung and skin tissues in rats. In order to detect or quantify the sodium cyanide in above biological matrixes, it was derivatized to Pentafluorobenzyl cyanide (PFB-CN) using pentafluorobenzyl bromide (PFB-Br) and then reaction substance was analyzed using gas chromatography mass spectrometer (GC/MS)-SIM (selected ion monitoring) mode. The analytical method for cyanide determination was validated with respect to parameters such as selectivity, system suitability, linearity, accuracy and precision. No interference peak was observed for the determination of cyanide in blank samples, zero samples and lower limit of quantification (LLOQ) samples. The lowest limit detection (LOD) for cyanide was $10{\mu}M$. The linear dynamic range was from 10 to $200{\mu}M$ for cyanide with correlation coefficients higher than 0.99. For quality control samples at four different concentrations including LLOQ that were analyzed in quintuplicate, on six separate occasions, the accuracy and precision range from -14.1 % to 14.5% and 2.7 % to 18.3 %, respectively. The GC/MS-based method of analysis established in this study could be applied to the toxicokinetic study of cyanide on biological matrix substrates such as blood, urine, lung and skin tissues.

First Derivative Spectrophotometric and Gas-Liquid Chromatographic Determination of Caffeine in Foods and Pharmaceuticals III. Simultaneous assay of caffeine and some antihistaminics

  • Abdel-Moety, Ezzat M.;El-Tarras, Mohamed F.;El-Zeany, Badr-Eldin A.;Kelani, Khadiga O.
    • Archives of Pharmacal Research
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    • v.13 no.3
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    • pp.215-220
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    • 1990
  • Two different, derivative spectrophotometric and gas-liquid chromatographic, procedures for direct quantitation of caffeine and some commonly dispensed antihistaminics in bulk forms, in their laboratory prepared mmixtures and in dosage formulations, have been investigated. The limit, sensitivity reproducibility and accuracy of each method were studied for each individual drug substance and in some usual pharmaceutical formulations.

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The Trend of Precedents about Calculation of Damage Compensation for Last Decade (손해배상액 산정에 관한 최근 10년간 판례의 동향 하(下))

  • Park, Young-Ho
    • The Korean Society of Law and Medicine
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    • v.11 no.1
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    • pp.397-445
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    • 2010
  • This thesis introduces the trends of korean courts' ruling on damages in medical malpractice cases for past 10 years. First of all, Korean courts' ruling have had a tendency to pay only non-economic damages for not taking the informed consent. If a doctor cannot get the informed consent from a patient, he compensate only non-economic damages for the infringement of self-determination rights of patient. It's enough for the plaintiff to prove the infringement of self-determination rights, if the plaintiff just want to get non-economic damages. The Korean Supreme court have ruled that if plaintiffs want to get economic damages for the infringement of self-determination rights or informed consent, plaintiffs must prove that the infringement of self-determination rights is the proximate cause of the economic damages of patient. There is another tendency for the Korean Supreme court to limit the damages in medical malpractice cases on the ground of patient's diseases' dangerousness or patient's idiosyncrasy. In the past courts often limit the damages only to 70~80% of total damages, but now a days courts mostly limit the damages to 20~30%. This thesis also introduce the Korean courts' trends about Valuing damages in personal injury actions awarded for gratuitously rendered nursing and medical care.

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A Study on Effects of SSSC Controllers on Interface Flow Limit (SSSC 투입에 따른 연계선로조류의 윤용한계 증대)

  • Song, Hwa-Chang;Lee, Byong-Jun;Kwon, Sae-Hyuk;Kim, Seul-Ki
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.50 no.2
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    • pp.83-89
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    • 2001
  • This paper introduces a power flow model of SSSC for voltage stability analysis of power system installed with Static Synchronous Compensators. The SSSC model is obtained from the injection model of voltage source inverter by adding the condition that SSSC injection voltage is in quadrature with current of SSSC-installed branch. This model is incorporated into modified CPF algorithm to study effects of SSSC on the security-constrained interface flow limit. Determination of interface flow limit is simply briefed. In case study a 771-bus real system is used to show that interface flow limit can be improved by appropriate control of SSSC in terms of voltage stability.

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Determination of Methyl Bromide Used for the Preservation of Cultural Materials from Insects

  • Lee, Gil-Seung;Shin, Ueon-Sang;Shin, Ho-Sang
    • Journal of Environmental Health Sciences
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    • v.28 no.4
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    • pp.27-30
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    • 2002
  • A thermal desorption-gas chromatography/mass spectrometric method was developed for the determination of methyl bromide in fumes formed during preservation of cultural materials from insects. Methyl bromide in lunes was collected by drawing 10ι of air through the adsorbent tube filled with a solid adsorbent (Chromosorb). The air samples were analyzed by using a special thermal desorption device and GC/MS determination. The recovery of methyl bromide by air sampling was 88% and the detection limit of the assay was 0.1 pptv based upon assayed air of 10ι. The method was applied to the determination of fumed methyl bromide used for the preservation of papers in a library. The mean concentration of methyl bromide determined in a library was 280.2 $\pm$ 25.4 pptv.

Determination of burnup limit for CANDU 6 fuel using Monte-Carlo method

  • Lee, Eun-ki
    • Nuclear Engineering and Technology
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    • v.53 no.3
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    • pp.901-910
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    • 2021
  • KHNP recently has obtained the approval for the commercialization of the modified 37-element (or 37 M) fuel bundle and now is loading the 37 M fuel bundles in CANDU-6 reactors in KOREA. One of the main issues for approval was the burnup limit. Due to CANDU design and neutronic characteristics, there was no specific burnup restriction of a fuel bundle. The absence of a burnup limit does not mean that a fuel bundle can stay in the CANDU reactor without a time limit. However, the regulator requested traditional design values as well as the burnup limit reflecting the computer code uncertainty. The method for the PWR burnup limit was not applied to the CANDU fuel bundle. Since there was no approved methodology to build the burnup limit with uncertainties, KHNP introduced a Monte-Carlo method coupled with a 95/95 approach to determine the conservative burnup limit from the viewpoint of the centerline temperature, internal pressure, strain measurement deviation. Moreover, to consider the uncertainties of various computing models, a converted power uncertainty was introduced. This paper presents the methodology and puts forward the limits on burnup, evaluated for each of the existing and modified fuel bundles, in consideration of the pressure tube aging condition.

Determination of Optimal Mean Value and Screening Limit for a Production Process with Logistic Function (로지스틱 함수를 갖는 생산공정에 대한 최적공정평균 및 스크리닝 한계선의 결정)

  • Hong, Sung Hoon
    • Journal of Korean Institute of Industrial Engineers
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    • v.29 no.3
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    • pp.239-246
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    • 2003
  • Individual items are produced continuously from an industrial process. Each item is checked to determine whether it satisfies a lower screening limit for the quality characteristic which is the weight of an expensive ingredient. If it does, it is sold at a regular price; if it does not, it is reprocessed or sold at a reduced price. The process mean may be adjusted to a higher value in order to reduce the proportion of the nonconforming items. Using a higher process mean, however, may result in a higher production cost. In this paper, the optimal process mean and lower screening limit are determined in situations where the probability that an item functions well is given by a logistic function of the quality characteristic. Profit models are constructed which involve four price/cost components; selling prices, cost from an accepted nonconforming item, and reprocessing and inspection costs. Methods of finding the optimal process mean and lower screening limit are presented and numerical examples are given.