• 제목/요약/키워드: Analysts

검색결과 386건 처리시간 0.028초

Determination of Cadmium, Chromium and Lead in Polymers by ICP-OES Using a High Pressure Asher (HPA)

  • Cho, Hong-Je;Myung, Seung-Woon
    • Bulletin of the Korean Chemical Society
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    • 제32권2호
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    • pp.489-497
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    • 2011
  • The proposed method for an effective assay of Cd, Cr and Pb in several polymer samples has been validated. The determination was carried out using ICP-OES after a high pressure asher (HPA) digestion at pressure and temperatures up to 13 MPa and $320^{\circ}C$, respectively. Polymer based materials were totally oxidized with nitric acid in a HPA chamber and determined by ICP-OES. Validation parameters such as linearity, matrix effect, limit of dectection (LOD), limit of quantitation (LOQ), accuracy and precision (repeatibility, intermediate precision and reproducibility) were assessed. The LOD and LOQ in the sample were ranged from 0.98 to 1.18 mg $kg^{-1}$ and 2.93 to 3.55 mg $kg^{-1}$, respectively, relying on the analyte. The proposed method had a good accuracy and precision for repeatability, intermediate precision with respect to days and analysts and reproducibility expressed as inter-laboratory study. The developed method was simple to use, suitable and applicable to various kinds of polymers.

의사결정지원 모형을 통한 우리나라 주요 도시의 대기청명도 평가 (Atmospheric Clearness Estimation of Major Cities in Korea Using Decision Support Models)

  • 조덕기;전일수;강용혁;전명석;오정무
    • 한국태양에너지학회 논문집
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    • 제22권1호
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    • pp.55-65
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    • 2002
  • Since the atmospheric clearness index is one of the main factors for evaluating atmospheric circumstances, it is necessary to estimate its characteristics all over the cities in Korea. This study was focused on the evaluation of atmospheric condition for each 15 cities in terms of respectively or mutually analyzed clearness factor that was predicted on the assumed clear day with the model using factors such as average global insolation, cloud amount, and duration of sunshine measured for two years between 1999 and 2000. The new clearness index data will be extensively used by atmospheric circumstances analysts as well as by solar application designers or users.

인지과정모형에 기반한 원자력발전소 인적오류 분석 (Human error analysis in nuclear power plants based on a cognitive model)

  • 윤완철;이용희;김영수
    • 대한인간공학회지
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    • 제13권2호
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    • pp.33-41
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    • 1994
  • The paper presents a new scheme and a support system for the analysis sof hyman errors in nuclear power plants based on a cognitive model. We discusse the problems identified in current managerial analysis, and propose a new approach that frames the description of human activities according to a human decision making modle, so that it could provide a better reconstruction of a sequence of event suspected of involving human errors. This sophistcated approach becomes practical for the field application with the support of a computerized aiding system. The model-based event re-construction method is expected to enable the analysts to produce more informative reports, which in turn heop to derive appropriate counter- measures to reduce the possibility of the analyzed human errors.

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철도화물의 원가구조분석에 관한 연구 (An Analysis of the Cost Structure of Railway Freight Industry in Korea)

  • 권용장;김현웅
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 춘계학술대회 논문집
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    • pp.1115-1124
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    • 2005
  • The usual distinction made in the literature is between decision facilitating and decision influencing. Because time only runs one way, both uses of cost information are problematic. In the first instance, a cost description (measurement or estimate) is provided to decision makers before a decision is made. Unfortunately, costs can only be measured after the fact. This means that cost analysts must estimate the costs of the alternatives under consideration. In some cases, measured cost is a reliable predictor of future costs; in other cases it is not. Regardless of its reliability, however, it is all we have or can have. Consequently, managers must be informed as to how their performance will be measured and how measured performance will affect outcomes they care about -- promotion, pay, esteem, etc. I will outline the basic approaches to cost measurement and then show how cost measures can be used to facilitate and to influence decisions of the railway industry.

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대체안의 순현재가치 평가와 내부수익율 유도에 대한 연구 (The Evaluation of the Net Present Value and the Derivation of the Internal Rate of Return with the Alternatives)

  • 박상민;이근희
    • 산업경영시스템학회지
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    • 제17권29호
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    • pp.30-36
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    • 1994
  • This paper has provided a systematic technique, the evaluation of the distribution with the NPV ana the derivation of the IRR in the investment alternatives, for the cost estimating analysts. The proposals of investment alternatives are included the venture capital under risk and probabilities at each events, within the cash inflows are occuring at random timing. Therefore. we have considered the followings : 1) the first cash outflow is deterministic. 2) the cash inflows are random variables with known distributions. 3) the lengths of the time intervals between the cash inflows are independently distributed and independent of the cash inflows. In this paper. the first two moments of the distribution, the Laplace Transforms and the convolutions are computed for both independent cash inflows and mutually exclusive alternatives as in the case of quite correlated cash inflows.

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통계적 에너지 해석 모델을 이용한 건설 장비 차실 설계에 관한 연구 (Design Sensitivity Studies for Statistical Energy Analysis Modeling of Construction Vehicle Cab)

  • 채장범
    • 소음진동
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    • 제8권4호
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    • pp.609-615
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    • 1998
  • In recent years there has been an increasing emphasis on shortening design cycles for bringing products to market. This requires the development of computer aided engineering tools which allow analysts to quickly evaluate the effect of design changes on noise, vibration, and harshness. Statistical Energy Analysis (SEA) modeling is a valuable tool for predicting noise and vibration as SEA models are inherently simpler and more robust than deterministic models. SEA modeling can be combined with design sensitivity analysis(DSA) to identify design changes which give the largest performance benefit. This paper describes SEA modeling of an equipment cab. SEA predictions are compared to test data, showing good agreement. The use of design sensitivity analysis in improving cab design is then demonstrated.

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Development of Performance Demonstration Programs for Eddy Current Data Analysis

  • Cho, Chan-Hee;Nam, Min-Woo;Yang, Seung-Han;Yang, Dong-Soon;Lee, Hee-Jong
    • 비파괴검사학회지
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    • 제25권3호
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    • pp.228-232
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    • 2005
  • The Korea Electric Power Research Institute (KEPRI) has developed performance demonstration programs for non-destructive testing personnel who analyze ECT(eddy current testing) data for steam generator tubing since 2001 The purpose of these performance demonstration programs is to ensure a uniform knowledge and skill level of data analysts and contribute to safe operation of nuclear power plants. Many changes have occurred in non-destructive testing of steam generator tubing such as inspection scope, plugging criteria and qualification requirements. According to the Notice 2004-13 revised by the Ministry of Science and Technology (MOST), the analyst for steam generator tubing shall be qualified as the qualified data analyst (QDA), and the site specific performance demonstration (SSPD) program shall be implemented. KEPRI developed these performance demonstration programs and they are being successfully implemented. The analyst's performance is expected to be improved by the implementation of these programs.

NIIRS ESTIMATION USING THE GENERAL IMAGE-QUALITY EQUATION FOR MONITORING IMAGE DEGRADATION

  • Kim, Dong-Wook;Kim, Tae-Jung;Kim, Hee-Seob
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.53-56
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    • 2008
  • Generally, the quality of satellite images is expressed by GSD (Ground Sample Distance), MTF (Modulation Transfer Function) and SNR (Signal to Noise Ratio). However, these factors are technology-oriented and do not explain interpretability of satellite images. We need a standardized index which shows standard of interpretability. In this study, we estimated NIIRS (National Imagery Interpretability Rating Scale) through the GIQE (General Image Quality Equation) which is able to judge image interpretability with the standardized index. Traditionally, NIIRS has been determined manually by specialized image analysts. We used the GIQE in order to reduce inefficiency and high costs cause by manual interpretation and to produce accurate NIIRS. For monitoring image degradation, we estimated GIQE physical parameters from image analysis and carried out time series analysis about the quality of the KOMPSAT-1 images. On all of the tests, we were able to identify the image degradation due to the changing time. This indicates that NIIRS derived from GIQE will be used for image degradation indicator.

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ADAPTIVE NUMERICAL SOLUTIONS FOR THE BLACK-SCHOLES EQUATION

  • Park, H.W.;S.K. Chung
    • Journal of applied mathematics & informatics
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    • 제12권1_2호
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    • pp.335-349
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    • 2003
  • Almost all business are affected by the weather so that weather derivatives has been traded to hedge weather risk. Since the weather itself is not an asset with a market price, some analysts believe that the Black-Scholes equation could not be used appropriately to price weather derivative options. But some weather derivatives can be considered as an Asian option, we revisit the Black-scholes model. Numerical solution of the Black-Scholes equation has a significant error at the money option or around the money option, it is necessary to adopt adaptive mesh near to the strike value. Here we propose a numerical method with an adaptive grid refinement.

Dilemma of Saudi Arabian Construction Industry

  • Albogamy, Abdullah;Scott, Darren;Dawood, Nashwan
    • Journal of Construction Engineering and Project Management
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    • 제3권4호
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    • pp.35-40
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    • 2013
  • Currently, the Kingdom of Saudi Arabia (KSA) is the epicentre of building services engineering encapsulating the construction industry. On rise of technological advancements, engineers have the ease to thoroughly investigate engineering aspects. Not only engineers, but other stakeholders, tender related people, financial analysts work in parallel as well. However, there are some factors that are stumbling blocks in the way of progression including delaying factors in the construction industry. The paper provides deep insights of delaying factors regarding public building projects of the KSA. Collection of primary data was carried out by conducting a survey which comprised of 63 chief delay factors. Professionals related to construction industry were asked for ranking the factors in terms of their frequency of occurrence and degree of impact. Seven groups of risk factors are categorized and a correlation analysis is performed by identifying the correlation amongst the variables. Finally, 31 leading delay factors are extracted and reported.