• Title/Summary/Keyword: Simple assessment

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DETERMINISTIC EVALUATION OF DELAYED HYDRIDE CRACKING BEHAVIORS IN PHWR PRESSURE TUBES

  • Oh, Young-Jin;Chang, Yoon-Suk
    • Nuclear Engineering and Technology
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    • v.45 no.2
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    • pp.265-276
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    • 2013
  • Pressure tubes made of Zr-2.5 wt% Nb alloy are important components consisting reactor coolant pressure boundary of a pressurized heavy water reactor, in which unanticipated through-wall cracks and rupture may occur due to a delayed hydride cracking (DHC). The Canadian Standards Association has provided deterministic and probabilistic structural integrity evaluation procedures to protect pressure tubes against DHC. However, intuitive understanding and subsequent assessment of flaw behaviors are still insufficient due to complex degradation mechanisms and diverse influential parameters of DHC compared with those of stress corrosion cracking and fatigue crack growth phenomena. In the present study, a deterministic flaw assessment program was developed and applied for systematic integrity assessment of the pressure tubes. Based on the examination results dealing with effects of flaw shapes, pressure tube dimensional changes, hydrogen concentrations of pressure tubes and plant operation scenarios, a simple and rough method for effective cooldown operation was proposed to minimize DHC risks. The developed deterministic assessment program for pressure tubes can be used to derive further technical bases for probabilistic damage frequency assessment.

A Study for the Measurement System Assessment (측정시스템 평가에 관한 연구)

  • 백재욱
    • Journal of Korean Society for Quality Management
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    • v.26 no.4
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    • pp.124-142
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    • 1998
  • It is essential to have a correct measurement system assessment to help improve process or quality. In this paper, we emphasize that a confidence interval a, pp.oach for the parameters of measurement error study and GR&R is crucial and a simple a, pp.oach for constructing them is presented. We also discuss on the issue of linearity of the gauge. Next, we try to reveal the relationship between measurement error and the process capability index. Finally some aspects of conducting the measuring experiment concerning the number of parts, number of measurements per part, and recommendations on how the experiment is to be performed will be considered.

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Establishment of Landfill Site Preliminary Assessment Model Based on Contamination Characteristics of Water Resources (수자원(水資源) 오염 특성에 의한 불량매립지(不良埋立地) 예비평가모형(豫備評價模型) 정립)

  • Hong, Sang-Pyo;Kim, Jung-Wuk
    • Journal of Environmental Impact Assessment
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    • v.4 no.1
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    • pp.17-23
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    • 1995
  • To assess preliminarily the contamination potential of water resources including groundwater owing to the hydrogeological characteristics of landfill site and the potential impact to humans and animals through contamination of water resources by leachate, "Landfill Site Preliminary Assessment Model(LASPAS)" was contrived. LASPAS could help them proritization of remediation of landfil sites by the convenient and relatively simple evaluation method of landfill site features. LASPAS was designd to aliot numerical ratings to landfill site related factors undermentioned; 1) hydrogeological factors such as hydraulic conductivity of aquifer, thickness of confining layer over aquifer, topographical slope, net recharge, and subsurface containment 2) water resources contamination factors of impacts on receptors such as proximity to drinking water supply, substitutability of drinking water supply, type of use of water resources, known impact on drinking water supply, and flood potential.

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Formulation of Fire Reliability Assessment Method for Structural Strength (화재 구조강도에 대한 신뢰성 평가방법의 정립)

  • 양영순;유원선;이상엽
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.04a
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    • pp.161-168
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    • 2004
  • This study describes the behavior and failure probability of basic structural member in case of fire for the research of safety assessment on onshore structure. Fire safety assessment can be done by comparing fire resistance of members with fire severity of heat load For more Practical applications, the commercial structural analysis program is linked with the in-house code and gets the limiting temperature by analyzing structural strength of member with elasto-plastic analysis and large deflection analysis. AFOSM method is utilized to obtain the failure probability against the fire. The examples of rather simple structures such as beams and plates are applied to explain and verify the procedure of fire safety assessment.

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Uncertainty Assessment Using Monte Carlo Simulation in Gas Flow Measurement (기체 유량 측정에서 몬테 카를로 모사를 이용한 측정불확도 평가)

  • Lee, Dae-Sung;Yang, In-Young;Kim, Chun-Taek;Yang, Soo-Seok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.12
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    • pp.1758-1765
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    • 2003
  • Monte Carlo simulation(MC) method was used as an uncertainty assessment tool for gas flow measurement in this paper. Uncertainty sources for gas flow measurement were analyzed, and probability distribution characteristics of each source were discussed. Detailed MC methodology was described including the effect of the number of simulation. The uncertainty result was compared with that of the conventional sensitivity coefficient method, and it was revealed that the results were different from each other for this particular gas flow measurement case of which the modelling equation was nonlinear. The MC was comparatively simple, convenient and accurate as an uncertainty assessment method, especially in cases of complex, nonlinear measurement modelling equations. It was noted that the uncertainty assessment method should be selected carefully according to the mathematical characteristics of the measurement.

Assessment of pain and adequacy of pain management in hospitalized cancer patients

  • Shin, Yeonghee
    • Journal of Korean Academy of Nursing
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    • v.29 no.5
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    • pp.1113-1122
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    • 1999
  • The author investigated pain experiences of 90 cancer patients and the adequacy of pain treatment they have received during their stay at a large medical center in T city between October 1994 and August 1995. Pain was assessed by the Shortened BPQ and results are summarized as follows: As for ratings of “worst pain” during the 24 hour period, 70% of the patients reported they had “severe” pain. As for ratings on “pain now,” 43% of the cancer patients reported “moderate to severe” pain. Over 46% of the patients reported a pain relief score of 0(not at all) or 1(somewhat) even after receiving pain medication. Adequacy of analgesic treatment was evaluated by comparing the patient's reported level of pain and the analgesic use, namely, the pain management index(PMI). The PMI indicated that 58% of the patients were undertreated for the pain control. In review of nurse's notes. systematic pain assessment was scarcely recorded, although pain documentation appeared in 70% of the notes; and the contents were mostly simple description. In conclusion, the results of patient's pain ratings, the PMI and poor pain documentation in the nurse's notes implied poor pain assessment and management.

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An Estimation of Landslide's Vulnerability by Analysis of Static Natural Environmental Factors with GIS (GIS를 이용한 정적 자연환경인자의 분석에 의한 산사태 취약성 평가)

  • Yang, In-Tae
    • 한국지형공간정보학회:학술대회논문집
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    • 2005.08a
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    • pp.61-72
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    • 2005
  • The landslide risk assessment process consists of hazard risk assessment and vulnerability analysis. landslide hazard risk is location dependent. Therefore, maps and spatial technologies such as GIS are very important components of the risk assessment process. This paper discusses the advantages of using GIS technology in the risk assessment process and illustrates the benefits through case studies of live projects undertaken. The goal of this study is to generate a map of landslide vulnerability map by analysis of static natural factors with GIS. A simple and efficient algorithm is proposed to generate a landslide potentialities map from DEM and existing maps. The categories of controlling factors for landslides, aspect of slope, soil, vegetation are defined. The weight values for landslide potentialities are calculated from AHP method. Slope and slope-direction are extracted from DEM, and soil informations are extracted from digital soil map. Also, vegetation informations are extracted from digital vegetation map. Finally, as overlaying, landslide potentialities map is made out, and it is verified with landslide place.

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RISK ASSESSMENT USING BIM BASED SAFETY MANAGEMENT SYSTEM

  • Hongseob Ahn;Hyunjoo Kim;Wooyoung Kim
    • International conference on construction engineering and project management
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    • 2011.02a
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    • pp.107-110
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    • 2011
  • The key role in safety management is to identify any possible hazard before it occurs by identifying any possible risk factors which are critical to risk assessment. This planning/assessment process is considered to be tedious and requires a lot of attention due to the following reasons: firstly, falsework (temporary structures) in construction projects is fundamentally important. However, the installation and dismantling of those facilities are one of the high risk activities in the job sites. Secondly, temporary facilities are generally not clearly delineated on the building drawings. It is our strong belief that safety tools have to be simple and convenient enough for the jobsite people to manage them easily and be flexible for any occasions to be occurred at various degrees. In order to develop the safety assessment system, this research utilizes the BIM technology and collects important information by importing data from BIM models and use it in the planning stage.

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Recurrent simple bone cyst of the mandibular condyle: a case report

  • Kim, Kyoung-A;Koh, Kwang-Joon
    • Imaging Science in Dentistry
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    • v.43 no.1
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    • pp.49-53
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    • 2013
  • Cysts of the mandibular condyle are rare and can be difficult to diagnose and treat. Clinically, a simple bone cyst is asymptomatic and often discovered incidentally on routine radiographic examination. This report shows an atypical simple bone cyst occurring in the mandibular condyle showing recurrence after surgical curettage. Radiologically, this lesion involving the mandibular condyle should be distinguished from other similar lesions such as a chondroma, a central giant cell granuloma, and an aneurysmal bone cyst. Radiographic assessment was useful for forecasting the prognosis of a simple bone cyst. Possible reasons for the recurrence were discussed radiographically.

A Study on Development of Simple System for Assessment of Uninsured Cost (비보험비용 산정을 위한 Simple System 개발에 관한 연구)

  • Lee, Jong-Bin;Lee, Tae-Yeong;Chang, Seong-Rok
    • Journal of the Korean Society of Safety
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    • v.26 no.4
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    • pp.96-101
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    • 2011
  • In previous studies, a system was developed for classifying items of uninsured cost and for generating factors and formulas by item for calculating accident loss costs. However, the loss cost of stopped production was not considered when the system was being developed. In addition, the system which was developed in previous studies had problems such as input error and data collection, owing to numerous input items. Therefore, this study developed a Revised system which considers the loss cost of stopped production, and a Simple system for improving the problems in input errors and data collection. In this study, unquantifiable factors were not considered. Further study that takes these factors into consideration is necessary.