• Title/Summary/Keyword: Sampling inspection

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Seismic Safety Assessment of Containment Building (격납건물의 내진안전성 평가)

  • Lee, Seong-Lo;Bae, Yong-Gwi
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.8 no.3
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    • pp.225-233
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    • 2004
  • In this study, the seismic safety of containment building is assessed using response surface method. The structural analyses considering random variables such as load, resistance and analysis by ABAQUS are performed to obtain the structural response. The structural response is represented by polynomial of random variables, and the reliability analysis is performed by Level II method. Drucker-Prager failure criterion is applied as limit state function to take bi-axial stress states into account in the concrete. The lifetime probability of failure is evaluated by considering the lifetime of containment building, the annual occurrence rate of earthquake and the conditional probability of failure. Also the sensitivity analysis on the selection of sampling points is performed to obtain the steady results from response surface method.

A Study on the Strength Prediction of Crushed Sand Concrete by Ultra-sonic Velocity Method (초음파속도법에 의한 부순모래 콘크리트의 강도 추정에 관한 연구)

  • Kim, Myung-Sik;Baek, Dong-Il;Youm, Chi-Sun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.11 no.4
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    • pp.71-78
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    • 2007
  • Schmidt hammer and ultra-sonic method are commonly used for crushed sand concrete compressive strength test in a construction field. At present, various of equations for prediction of strength are present, which have been used in a construction field. The purpose of this study is to evaluate the correlation between prediction strength by presentation equations and destructive strength to test specimen, and find out which is a suitable equation for the construction site. In this study, a strength test was carried out destructive test by means of core sampling and traditional test. The experimental parameter were concrete age, curing condition, and strength level.

Training Data Sets Construction from Large Data Set for PCB Character Recognition

  • NDAYISHIMIYE, Fabrice;Gang, Sumyung;Lee, Joon Jae
    • Journal of Multimedia Information System
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    • v.6 no.4
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    • pp.225-234
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    • 2019
  • Deep learning has become increasingly popular in both academic and industrial areas nowadays. Various domains including pattern recognition, Computer vision have witnessed the great power of deep neural networks. However, current studies on deep learning mainly focus on quality data sets with balanced class labels, while training on bad and imbalanced data set have been providing great challenges for classification tasks. We propose in this paper a method of data analysis-based data reduction techniques for selecting good and diversity data samples from a large dataset for a deep learning model. Furthermore, data sampling techniques could be applied to decrease the large size of raw data by retrieving its useful knowledge as representatives. Therefore, instead of dealing with large size of raw data, we can use some data reduction techniques to sample data without losing important information. We group PCB characters in classes and train deep learning on the ResNet56 v2 and SENet model in order to improve the classification performance of optical character recognition (OCR) character classifier.

A Study on the On-site Flame Resistant Inspection Method by X-ray Fluorescence Spectrometer (X-선 형광분석기를 이용한 현장방염검사방법에 관한 연구)

  • Kim, Hwang-Jin;Lee, Sung-Eun
    • Fire Science and Engineering
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    • v.30 no.5
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    • pp.124-129
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    • 2016
  • According to the current law, on-site flame resistant-treated interior decorations should pass the flame resistant performance test through a 45 degree combustion test from the district fire department. Although a 45 degree combustion test is the most accurate method for determining the flame resistant performance, it can be unreliable when tested on unauthorized samples. To avoid unauthorized sampling, this study suggests on-site flame resistant inspection by X-ray fluorescence spectrometer. Ten types of flame resistant paint were spread on plywoods and MDFs and the components were analyzed by X-ray fluorescence spectrometer. As a result, due to a difference amounts of substances in each paint, each flame resistant paints showed its own characteristic spectrum and the contents of each substance could be determined. On-site flame resistant inspections can be used efficiently when institutional procedures are created.

Small-Sample Inspection Plans for the New Product Quality Level Evaluation of Finite Population : Focused on Guided Weapons in Development Stage (생산수량이 한정된 신제품의 품질수준 평가를 위한 샘플링검사 방법 : 개발단계 유도무기를 중심으로)

  • Shin, Byung-Cheol;Byun, Jai-Hyun;Lee, Chang-Woo;Lee, Ki-Yong;Choi, Jong-Soo;Woo, Hee-Sung;Seo, Bo-Gil
    • Journal of Korean Institute of Industrial Engineers
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    • v.41 no.5
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    • pp.481-487
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    • 2015
  • In the product development stage, it is very important to ensure demanded quality level before moving to the full-scale manufacturing. For example, in developing guided weapons, live-fire tests are required to verify the final performance of the weapons which are very expensive. The quality evaluation of the guided weapons needs destructive testing, which makes it necessary to test as small number of samples as possible. This paper presents sampling inspection plans and calculating system for finite population guided weapons, which can meet the demanded quality level and confidence level with the minimum number of performance tests. The result of this paper can be useful for any kind of costly destructive testing.

A Study for Qualitative Performance of Asbestos Inspection/Analysis Labs in Korea (국내석면조사기관의 질적 수준 평가를 위한 현황조사)

  • Choi, Sungwon;Kwon, Jiwoon;Baek, Jung Eun;Jang, Kwang Myong;Kim, Dae Jong;Kim, Hyunwook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.24 no.4
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    • pp.501-508
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    • 2014
  • Objectives: This study identified the general characteristics of asbestos inspection/analysis laboratories in Korea and confirmed the actual situations in terms of technical aspects from these characteristics. In addition, given the background of the current problem, it offers preliminary data for determining future plans for improvement. Methods: A questionnaire was developed and distributed to the asbestos inspection/analysis laboratories that used the ISO/IEC 17025 for asbestos sampling and testing by UKAS(United Kingdom Accreditation Service) and the Korea Laboratory Accreditation Scheme(KOLAS). A total of 202 institutions in Korea were selected for the study and 145(71.8%) questionnaires were returned. Results: The number of personnel of the surveyed institutions averaged $4.2{\pm}2$ and 79.3% operated with less than five persons. In terms of education, the capital and other densely populated areas showed a high level of education(p<0.05). The level of education and facilities were determined by the magnitude of the institution(p<0.05). Institutions managed by highly educated directors were well-stocked with education and facilities(p<0.05). Institutions which had directors with considerable experiences received high scores overall and in particular higher scores in terms of education and facilities(p<0.05). At the level of the bottom five percent, the factor of education was 40.4% while the factor of measurement 49%, the factor of analysis 59%, the factor of facilities 61%, and the factor of survey 81%, respectively. Conclusions: To improve the quality of the institutions, in the short term, the problems identified in this study can be used to revise the related regulations. In the long term, a grading system of survey institutions needs to be established through the introduction of an accreditation system. However, the ongoing support of a government agency is required, including holding seminars and open education, suggesting guidelines for operation of asbestos inspection/analysis labs, and other means.

Analytical Method Development and Monitoring of Residual Solvents in Dietary Supplements (건강기능식품 중 잔류용매 분석법 개발 및 모니터링)

  • Lee, Hwa-Mi;Shin, Ji-Eun;Jang, Young-Mi;Kim, Hee-Yun;Kim, Mee-Hye
    • Korean Journal of Food Science and Technology
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    • v.42 no.4
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    • pp.390-397
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    • 2010
  • Residual solvents in foods are defined as organic volatile chemicals used or produced in manufacturing of extracts or additives, or functional foods. The solvents are not completely eliminated by practical manufacturing techniques and they also may become contaminated by solvents from packing, transportation or storage in warehouses. Because residual solvents have no nutritional value but may be hazardous to human health, there is a need to remove them from the final products or reduce their amounts to below acceptable levels. The purpose of this study was to develop and evaluate an analytical method for the screening of residual solvents in health functional foods. Furthermore, the aim of this study was to constitute a reasonable management system based on the current state of the market and case studies of foreign countries. Eleven volatile solvents such as MeOH, EtOH, trichloroethylene and hexane were separated depending on their column properties, temp. and time using Gas Chromatography (GC). After determining the GC conditions, a sample preparation method using HSS (Head Space Sampling) was developed. From the results, a method for analyzing residual solvents in health functional foods was developed considering matrix effect and interference from the sample obtained from the solution of solvents-free health functional foods spiked with 11 standards solutions. Validation test using the developed GC/HSS/MS (Mass Spectrometry) method was followed by tests for precision, accuracy, recovery, linearity and adequate sensitivity. Finally, examination of 104 samples grouped in suits was performed by the developed HSS/GC/MS for screening the solvents. The 11 solvents were isolated from health functional foods based on vapor pressure difference, and followed by separation within 15 minutes in a single run. The limt of detection (LOD), limit of quantification (LOQ), recovery and coefficient of variation (C.V.) of these compounds determined by the HSS/GC/MS were found to be 0.1 pg/mL, 0.1-125 pg/g, 51.0-104.6%, and less than 15%, respectively. Using the developed HSS/GC/MS method, residual solvent from 16 out of 104 health functional products were detected as a EtOH. This method therefore seems t o be a valuable extension ofanalytical method for the identification of residual solvents in health functional food.

FACTORS INVOLVED IN DEVELOPMENT OF ELECTRONIC SYSTEMS FOR GRADING GRAINS AND SEEDS

  • Williams, Phil
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.3121-3121
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    • 2001
  • The factors involved in development of electronic grading systems for commodities such as grains and seeds include determination of the factors that influence the end-product utilization of the commodities, and the degree to which these can be predicted by electronic methods. The possibility of exchanging existing methods of grading by electronic methods has to be considered. The respective merits of techniques such as Digital Imaging and Near-infrared (NIR) spectroscopy have to be considered. Digital Imaging is a computerized version of visual inspection and grading, whereas NIR spectroscopy has the potential for grading on the basis of composition and functionality, Selection and evaluation of NIR instruments is an important factor, as are sampling and sample presentation to electronic instruments, and particularly the engineering involved in sample presentation. Sample assembly, and software for calibration development are described in the presentation. Finally the impact and implications of introduction of electronic grading are discussed with particular attention to marketing of the commodities.

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Estimation of Qualities and Inference of Operating Conditions for Optimization of Wafer Fabrication Using Artificial Intelligent Methods

  • Bae, Hyeon;Kim, Sung-Shin;Woo, Kwang-Bang
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1101-1106
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    • 2005
  • The purpose of this study was to develop a process management system to manage ingot fabrication and the quality of the ingot. The ingot is the first manufactured material of wafers. Operating data (trace parameters) were collected on-line but quality data (measurement parameters) were measured by sampling inspection. The quality parameters were applied to evaluate the quality. Thus, preprocessing was necessary to extract useful information from the quality data. First, statistical methods were employed for data generation, and then modeling was accomplished, using the generated data, to improve the performance of the models. The function of the models is to predict the quality corresponding to the control parameters. The dynamic polynomial neural network (DPNN) was used for data modeling that used the ingot fabrication data.

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Probabilistic Evaluation Methodology for Nuclear Components (원전 주요기기의 확률론적 평가 기법)

  • Lee, Joon-Seong;Kwak, Sang-Log;Kim, Young-Jin;Park, Youn-Won
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.459-464
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    • 2001
  • For major nuclear power plant components periodic inspections and integrity assessments are needed for the safety. But many flaws are undetectable due to sampling inspection. Probabilistic integrity assessment is applied to take into consideration of uncertainty and variance of input parameters arise due to material properties, applied load and undetectable flaws. This paper describes a Probabilistic Fracture Mechanics(PFM) analysis based on Monte Carlo(MC) algorithms. Taking important parameters as probabilistic variables such as fracture toughness, crack growth rate and flaw shape, failure probability of major nuclear power plant components is archived as a results of MC simulation. For the verification of these analysis, a comparison study of the PFM analysis using other commercial code, mathematical method is carried out and a good agreement was observed between those results.

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