• Journal of Mechanical Science and Technology
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• 제18권9호
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• pp.1493-1499
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• 2004

This paper describes the speckle shearing interferometry, a non-destructive optical method, for quantitative estimation of void defect and monitoring separation defect inside of a pneumatic tire. Previous shearing interferometry has not supplied quantitative result of inside defect, due to effective factors. In the study, factors related to the details of an inside defect are classified and optimized with pipeline simulator. The size and the shape of defect can be estimated accurately to find a critical point and also is closely related with shearing direction. The technique is applied for quantitative estimation of defects inside of a pneumatic tire. The actual traveling tire is monitored to reveal the cause of separation and the starting points. And also unknown void defects on tread are inspected and the size and shape of defects are estimated which has good agreement with the result of visual inspection.

• Journal of Biosystems Engineering
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• 제32권5호
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• pp.324-331
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• 2007

The purpose of this study is to analysis effects of defect factors of combine header for cutting speed of combine header, feeding depth of straw, and cylinder speed of thresher. Measurement system for defect factors was consists of sensors to monitor the combine operation and I/O interface to convert the signals. Cutting speed of combine header, feeding depth of straw, cylinder speed of thresher were measured and analyzed. The data were collected from three paddy field during rice harvesting. The tests were conducted at different grounding speeds, lug troubles, and cutter condition. The one way ANOVA and the multiple comparison tests were performed. The results showed that the measured data were useful to monitor the defect factors of combine during harvesting. The faults conditions of grounding speeds, lug troubles, and cutter conditions affected cutting speeds, feeding depths and cylinder speeds of the combine. The data seem to be useful to analysis the faults conditions of combine header.

• 한국건축시공학회지
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• 제20권6호
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• pp.567-576
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• 2020

본 연구는 공동주택의 하자소송의 사례분석을 통해 하자소송단계에서 추가적으로 하자로 인정되는 하자 항목을 제안한다. 이 하자 항목은 하자소송에서 추가적인 비용의 증가, 일정 지연, 재감정 혹은 추가소송을 방지할 수 있을 것이다. 하자소송에서는 입주자 및 건설사에서 사전에 인지하지 못한 새로운 하자항목이 발생되며, 이를 새로운 하자인정항목으로 정의하였다. 이를 위해 본 연구에서는 국내의 15개의 하자소송의 사례분석을 실시하였다. 이를 통해 77개의 소송하자를 1차 선별하고 전문가 자문을 통해 최종적으로 23개의 소송하자를 도출하였다. 이후 하자의 요인을 분석하여 최종적으로 23개의 소송항목을 총 10개의 요인항목으로 정립하였으며, 사례연구를 통해 효용성을 분석하였다. 본 연구의 결과는 하자의 발생을 저감하고 분쟁을 최소화하는 데 기여할 수 있을 것이다.

• 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.

• 비파괴검사학회지
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• 제23권3호
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• pp.270-279
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• 2003

Parametric studies have been conducted into the variability of the factors affecting the ultrasonic testing applied to weldments. The influence of ultrasonic equipment, transducer parameters, test technique, job parameters, defect type and characteristics on reliability far defect detection and sizing was investigated by experimentation. The investigation was able to build up substantial bank of information on the reliability of manual ultrasonic method for testing weldments. The major findings of the study separate into two parts, one dealing with correlation between ultrasonic techniques, equipment and defect parameters and inspection performance effectiveness and other with human factors. Defect detection abilities are dependent on the training, experience and proficiency of the UT operators, the equipment used, the effectiveness of procedures and techniques.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.627-628
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• 2015

Construction defect which can causes economic damage such as schedule delay, cost overrun is a considerably important factor in construction industry. In general, a construction defect features a difficulty to find out causes precisely because it occurs when several interrelated causes combine. Yet, studies have tried to understand the interrelationships between factors are limited. In addition, despite of a tremendous amount of construction data, it's not still enough to analyze them, but tends to depend on experience or know-how of practitioners. Thus, it is necessary to identify underlying causes in influential factors by utilizing related data. This paper analyses Interrelationships between causal factors using Association Rule Mining to discover root causes of construction defects. Confidence and Lift that can be used for presenting the interrelationships of the causes were extracted from 1241 cases in 30 projects in Korea. It is expected that this paper allows the construction managers to discover key factors and make right decisions to reduce occurrence of construction defects. Furthermore, analysis of interrelationships can improve understanding of structural patterns of construction defects.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.158-159
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• 2014

There is urgent for defect consulting work to standardize the investigated method, repaired and reinforced method, and estimated cost about defect in increasing a defect lawsuit of apartment building. For the purpose of developing the standard process of defect consulting work, the review that a used process in law and institution should take precedence. There is not prepared the national standard for defect consulting but is dependent on an experience and a practice of consultants. This study analyzes defect consulting case, defines main steps for developing the standard process, and draws phased work factors. As systemizing this, it is expected to apply to basic structure for developing the standard process of defect consulting work for the next.

• 제어로봇시스템학회논문지
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• 제19권11호
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• pp.974-978
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• 2013

AVI (Automatic Vision Inspection) systems automatically detect defect features and measure their sizes via camera vision. AVI systems usually report different measurements on the same defect with some variations on position or rotation mainly because different images are provided. This is caused by possible variations from the image acquisition process including optical factors, nonuniform illumination, random noises, and so on. For this reason, conventional area based defect measuring methods have problems of robustness and consistency. In this paper, we propose a new defect size measuring method to overcome this problem, utilizing volume information that is completely ignored in the area based defect measuring method. The results show that our proposed method dramatically improves the robustness and consistency of defect size measurement.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.29-30
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• 2022

Tile defects in apartment houses are caused by a combination of various factors. These factors cannot be specified, and it is difficult to determine the exact cause because a number of causes are intertwined. In addition, because the climate of Korea is different by season, the coefficient of thermal expansion between materials is different, which is a major cause of tile defects. Therefore, this study analyzed the difference between the construction location and the period of defect occurrence according to the types of tile defects caused by environmental differences between indoor and outdoor environments. Two-way ANOVA was used, indoor and outdoor spaces were selected, and defect types were selected accordingly to show the difference in the occurrence period of each defect.

• Journal of Information Processing Systems
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• 제19권1호
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• pp.109-117
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• 2023

Defect detection is one of the key factors in fabric quality control. To improve the speed and accuracy of denim fabric defect detection, this paper proposes a defect detection algorithm based on cascading feature extraction architecture. Firstly, this paper extracts these weight parameters of the pre-trained VGG16 model on the large dataset ImageNet and uses its portability to train the defect detection classifier and the defect recognition classifier respectively. Secondly, retraining and adjusting partial weight parameters of the convolution layer were retrained and adjusted from of these two training models on the high-definition fabric defect dataset. The last step is merging these two models to get the defect detection algorithm based on cascading architecture. Then there are two comparative experiments between this improved defect detection algorithm and other feature extraction methods, such as VGG16, ResNet-50, and Xception. The results of experiments show that the defect detection accuracy of this defect detection algorithm can reach 94.3% and the speed is also increased by 1-3 percentage points.