• 제목/요약/키워드: defect rate

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Evaluation of peri-implant bone defects on cone-beam computed tomography and the diagnostic accuracy of detecting these defects on panoramic images

  • Takayuki Oshima;Rieko Asaumi;Shin Ogura;Taisuke Kawai
    • Imaging Science in Dentistry
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    • 제54권2호
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    • pp.171-180
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    • 2024
  • Purpose: This study was conducted to identify the typical sites and patterns of peri-implant bone defects on cone-beam computed tomography (CBCT) images, as well as to evaluate the detectability of the identified bone defects on panoramic images. Materials and Methods: The study population included 114 patients with a total of 367 implant fixtures. CBCT images were used to assess the presence or absence of bone defects around each implant fixture at the mesial, distal, buccal, and lingual sites. Based on the number of defect sites, the presentations of the peri-implant bone defects were categorized into 3 patterns: 1 site, 2 or 3 sites, and circumferential bone defects. Two observers independently evaluated the presence or absence of bone defects on panoramic images. The bone defect detection rate on these images was evaluated using receiver operating characteristic analysis. Results: Of the 367 implants studied, 167 (45.5%) had at least 1 site with a confirmed bone defect. The most common type of defect was circumferential, affecting 107 of the 167 implants(64.1%). Implants were most frequently placed in the mandibular molar region. The prevalence of bone defects was greatest in the maxillary premolar and mandibular molar regions. The highest kappa value was associated with the mandibular premolar region. Conclusion: The typical bone defect pattern observed was a circumferential defect surrounding the implant. The detection rate was generally higher in the molar region than in the anterior region. However, the capacity to detect partial bone defects using panoramic imaging was determined to be poor.

도시정비사건 소송의 본안전항변사유와 본안쟁점사항에 관한 분석 - 인용률 및 행렬표식 분석기법을 활용한 - (Analysis by Defensive Process Prerequisite and Offensive Cause of Action on the Merits of Lawsuit Cases in Urban and Housing Redevelopment - Based on Affirm-Rate and Staircase Matrix Tables -)

  • 김요한;정보선;이상엽
    • 한국건설관리학회논문집
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    • 제20권5호
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    • pp.104-114
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    • 2019
  • 본 연구는 부동산건설 관련된 대표적 소송인 도시정비사업의 시행주체인 조합설립과 관련된 소송의 승소요인에 대한 분석을 진행하였다. 이를 위해 조합설립인가 쟁송에 대한 전국의 제1심 행정법원 판결 441건을 분석대상으로 본안전항변사유와 본안전쟁점사항을 구분하여 계량법학적으로 승소확률표에 의한 빈도분석 및 계단식 예측방법에 의한 행렬표식 분석을 실행하였다. 인용률을 활용한 분석결과로 본안전항변사유와 관련하여 과거법률관계 항변, 인가고유하자아님 항변, 조합원지위 또는 소유권 없음 항변, 제소시간 도과 항변, 법률상이익 없음 항변 등, 본안쟁점사항과 관련하여 동의율하자산정, 동의서관련하자, 구역지정전승인, 총회관련하자, 구역지정하자 등의 순서로 빈도가 높은 것으로 파악되었다. 계단식 예측방식에 의한 행렬표식 분석을 통해 핵심예측변수인 '과거법률관계'와 '조합원지위 또는 소유권 없음'을 이용하여 본안승소판결에 미치는 영향을 분석하여 승패소구분을 위한 기준을 도출하였다. 이를 통해 도시정비사업에서 참여자별 소송결과의 예측가능성에 대한 이해도를 높이고 분쟁해결의 빈도를 낮춰 과다한 사회적 비용을 방지하는데 시사점을 제공하고자 한다.

자동차 안전벨트 부품 제조공정에서의 효율적 공정품질정보 분석 모형 (An Efficient Analysis Model for Process Quality Information in Manufacturing Process of Automobile Safety Belt Parts)

  • 공명달
    • 대한설비관리학회지
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    • 제23권4호
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    • pp.29-38
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    • 2018
  • Through process quality information, the time required for process quality analysis has been drastically shortened, the process defect rate has been reduced, and the manufacturing lead time has been shortened and the on-time delivery rate has been improved. Therefore, The purpose of this study is to develop a quality information analysis system model that effectively shortens the time required for process quality analysis in automobile safety belt parts manufacturing process. As a result of experiments on communication operation between manufacturing execution system (MES) quality server, injection machine control computer, injection machine programmable logic controller (PLC) and terminal, in analyzing quality information, the conventional handwriting input method took an average of 20 minutes, but the new multi-network method took about 2 minutes on average. In addition, the process defect rate was reduced by 13% and the manufacturing lead time was shortened from 28 hours to 20 hours. The delivery compliance rate improved from 96 to 99%.

A New Exploratory Testing Method for Improving the Effective IP Set-Top Box Test

  • Kim, Donghyun;Kim, Yoon
    • 한국컴퓨터정보학회논문지
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    • 제23권2호
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    • pp.9-16
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    • 2018
  • Recently, as various IP set-top boxes based on Android OS have been widely used in general households and public facilities, complaints about services and set-top boxes have continued to increase as much as other smart devices. In order to reduce this problem, the manufacturer performs the testing work before the product is commercialized. However, the testing can reduce potential defects in the product, but it can not prove that the product is free of defects. Therefore, the quality of the product can vary depending on how effective testing techniques are introduced. In this paper, we propose a new exploratory testing method that minimizes test case creation time and makes it easier to plan and execute test while simultaneously learning how to run the product under test. Using the first proposed method, the test time is reduced by about 16.7 hours and the defect detection rate is 25.4% higher than the formal specification-based testing method. Informally, the test time was shortened by about 4.7 hours and the defect detection rate was 13% higher than the informal experience-based testing method.

An Improved Defect Detection Algorithm of Jean Fabric Based on Optimized Gabor Filter

  • Ma, Shuangbao;Liu, Wen;You, Changli;Jia, Shulin;Wu, Yurong
    • Journal of Information Processing Systems
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    • 제16권5호
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    • pp.1008-1014
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    • 2020
  • Aiming at the defect detection quality of denim fabric, this paper designs an improved algorithm based on the optimized Gabor filter. Firstly, we propose an improved defect detection algorithm of jean fabric based on the maximum two-dimensional image entropy and the loss evaluation function. Secondly, 24 Gabor filter banks with 4 scales and 6 directions are created and the optimal filter is selected from the filter banks by the one-dimensional image entropy algorithm and the two-dimensional image entropy algorithm respectively. Thirdly, these two optimized Gabor filters are compared to realize the common defect detection of denim fabric, such as normal texture, miss of weft, hole and oil stain. The results show that the improved algorithm has better detection effect on common defects of denim fabrics and the average detection rate is more than 91.25%.

공동주택에서 하자관리 실태조사를 통한 공동주택 하자 유형 및 원인 분석 (A Study on the Cases and Factors of Defect Management in Apartment Housing)

  • 강상훈;박재우;손성근;박현정
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 추계 학술논문 발표대회
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    • pp.187-188
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    • 2019
  • The supply of apartments has continuously increased, and the housing supply rate has exceeded 100 percent and the demands and standards of tenants have also been raised as technology has developed. This has led to the conflict and caused social and economic losses. In this study, the case investigation and research methods of the prior research are analyzed as the basis for identifying the defects cases of causes and influences occurring in the apartment building. To analyze various studies, we divided the prior research into the defect management process and the study on the type of defects and countermeasures, and investigated the features and limitations. Future research will be conducted on apartment buildings within 10 years of completion among conglomerate's nationwide apartments to compensate for the limitations of prior research. In addition, AHP static method and relational chart will be used to identify the relationship between the type of defect and the cause and the importance of the influencing factors.

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결함크기 측정오차로 인한 오검률의 통계적 예측 (Statistical Prediction of False Alarm Rates in Automatic Vision Inspection System)

  • 주영복;허경무;박길흠
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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    • pp.163-165
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    • 2009
  • Automatic Vision Inspection(AVI) systems automatically detect defect features and measure their sizes via camera vision. It is important to predict the performance of an AVI to meet customer's specification in advance. In this paper, we propose a statistical method for prediction of false alarm rate regarding inconsistency of defect size measuremet process. We only need are a simple experimental trial for repeated defect size measurement test. The statistical features from the experiement are utilized in the prediction process. Therefore, the proposed method is swift and easy to implement and use. The experiment shows a close prediction compared to manual inspection results.

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공동주택 공사종류별 하자사례분석 (Analysis of Defect Cases by Construction Types in Apartments)

  • 고성석;송혁;이재홍
    • 한국안전학회지
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    • 제21권6호
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    • pp.64-73
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    • 2006
  • Due to the lack of available land for housing in Korea, apartment has been supplied in great quantities to raise the rate for land-use since the middle of 1980s. Many people in Korea live in apartment because the number of apartment occupies more than half of total houses. Nevertheless, the concern on the house management with respect to the quality is insufficient, it is currently required the concern on the quality of housing. Moreover, many defects in apartment has been occurred repeatedly now, so, it is necessary to analyze the defect in order to raise the quality of living environment. This study aimed to survey the types of defect in apartment according to the construction types through the questionnaire analysis about apartment residents in Gwangju city for the purpose of reducing the defects.

자동결함 검출시스템에서 결함크기 측정오차로 인한 오검률의 통계적 예측 (Statistical Prediction of False Alarm Rates in Automatic Vision Inspection System)

  • 주영복;허경무;박길홈
    • 제어로봇시스템학회논문지
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    • 제15권9호
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    • pp.906-908
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    • 2009
  • AVI (Automatic Vision Inspection) systems automatically detect defect features and measure their sizes via camera vision. It is important to predict the performance of an AVI to meet customer's specification in advance. Also the prediction can indicate the level of current performance of an AVI system. In this paper, we propose a statistical method for prediction of false alarm rate regarding inconsistency of defect size measurement process. For this purpose, only simple experiments are needed to measure the defect sizes for certain number of times. The statistical features from the experiment are utilized in the prediction process. Therefore, the proposed method is swift and easy to implement and use. The experiment shows a close prediction compared to manual inspection results.

The use of the buccal fat pad flap for oral reconstruction

  • Kim, Min-Keun;Han, Wonil;Kim, Seong-Gon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제39권
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    • pp.5.1-5.9
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    • 2017
  • Many congenital and acquired defects occur in the maxillofacial area. The buccal fat pad flap (BFP) is a simple and reliable flap for the treatment of many of these defects because of its rich blood supply and location, which is close to the location of various intraoral defects. In this article, we have reviewed BFP and the associated anatomical background, surgical techniques, and clinical applications. The surgical procedure is simple and has shown a high success rate in various clinical applications (approximately 90%), including the closure of oroantral fistula, correction of congenital defect, treatment of jaw bone necrosis, and reconstruction of tumor defects. The control of etiologic factors, size of defect, anatomical location of defect, and general condition of patient could influence the prognosis after grafting. In conclusion, BFP is a reliable flap that can be applied to various clinical situations.