• Title/Summary/Keyword: Inspection Technique

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The AHP Method to Quantitate Investigation Items of Cut Slope (계층분석과정을 통한 절토사면 조사항목의 정량화)

  • Lee, Jong-Young;Shin, Chang-Gun;Kim, Yong-Soo;An, Sang-Lo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.732-737
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    • 2006
  • The facility diagnosis technique of past subjective judged the technical expert and interpreted stably mainly. The facility the periodical civil official becomes indispensability consequently with the law and the system and objectivity inspection which relates with a this and development of diagnosis technique were necessary. Currently the evaluation elements which relate with an inspection and diagnosis technique depended to the subjectivity of each facility quality, data statistics, diagnosis know-how, various circumstance and the technical expert and the evaluation item came to decide. But the evaluation score distribution of marks of each item depended plentifully in data analysis result and experience. The past method is weak in logically because the objection theoretical background and basis are insufficiency. Consequently in order to apply a data analysis result and an experience logically, it used AHP(Analytic Hierarchy Process) method from this research. It is visible with the fact that the application result reconfirmation and complement process will be necessary the technique which is suitable in the multi facility management. Also it is expected with the fact that the application characteristic from the next relation technique will be excellent.

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Automated quality characterization of 3D printed bone scaffolds

  • Tseng, Tzu-Liang Bill;Chilukuri, Aditya;Park, Sang C.;Kwon, Yongjin James
    • Journal of Computational Design and Engineering
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    • v.1 no.3
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    • pp.194-201
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    • 2014
  • Optimization of design is an important step in obtaining tissue engineering scaffolds with appropriate shapes and inner micro-structures. Different shapes and sizes of scaffolds are modeled using UGS NX 6.0 software with variable pore sizes. The quality issue we are concerned is the scaffold porosity, which is mainly caused by the fabrication inaccuracies. Bone scaffolds are usually characterized using a scanning electron microscope, but this study presents a new automated inspection and classification technique. Due to many numbers and size variations for the pores, the manual inspection of the fabricated scaffolds tends to be error-prone and costly. Manual inspection also raises the chance of contamination. Thus, non-contact, precise inspection is preferred. In this study, the critical dimensions are automatically measured by the vision camera. The measured data are analyzed to classify the quality characteristics. The automated inspection and classification techniques developed in this study are expected to improve the quality of the fabricated scaffolds and reduce the overall cost of manufacturing.

Visual Inspection Method by Pyramid Data Structure (IC핀 조사를 위한 시각 조사 방법)

  • 최성진;조동래;김영해;나극환;김춘길
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.5
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    • pp.374-383
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    • 1990
  • For a visual inspectio system to be viable, it must in general achieve the same or lower costs as those incurred by manual methods, it must have a reasonable inspection rate, and it must be reliable and maintainable : for the visual inspection system, inspection at high speed, flexibility for variety of products, and low cost are needed. In order to solve these problems, we propose the visual inspection algorithm by divide-and-conquer technique using the pyramid data structure and the development of simplified pattern matching method. By this method we can reduce the number of data required to compare with patterns and make the inspection time short.

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Noise-robust Phase Gradient Retrieval Formulation for Phase-shifting Interferometry

  • Park, Dae-Seo;O, Beom-Hoan;Park, Se-Geun;Lee, El-Hang;Park, Jae-Hyun;Lee, Seung-Gol
    • Journal of the Optical Society of Korea
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    • v.14 no.2
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    • pp.131-136
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    • 2010
  • Modification of the phase gradient formulation is proposed in order to make phase retrieval less susceptible to noise. The modified formulation is derived from separation of the phase terms and the intensity modulation terms of interferograms, and subsequent differentiation to reduce the noise-induced error of the phase gradient vector. Its performance is evaluated and compared to that of the conventional formulation, and noise-robust nature is confirmed.

Comparison of Region-based CNN Methods for Defects Detection on Metal Surface (금속 표면의 결함 검출을 위한 영역 기반 CNN 기법 비교)

  • Lee, Minki;Seo, Kisung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.7
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    • pp.865-870
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    • 2018
  • A machine vision based industrial inspection includes defects detection and classification. Fast inspection is a fundamental problem for many applications of real-time vision systems. It requires little computation time and localizing defects robustly with high accuracy. Deep learning technique have been known not to be suitable for real-time applications. Recently a couple of fast region-based CNN algorithms for object detection are introduced, such as Faster R-CNN, and YOLOv2. We apply these methods for an industrial inspection problem. Three CNN based detection algorithms, VOV based CNN, Faster R-CNN, and YOLOv2, are experimented for defect detection on metal surface. The results for inspection time and various performance indices are compared and analysed.

Locating Mechanical Damages Using Magnetic Flux Leakage Inspection in Gas Pipeline System

  • Kim, Jae-Joon
    • Journal of the Korean Society for Nondestructive Testing
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    • v.30 no.6
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    • pp.521-526
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    • 2010
  • Gas transmission pipelines are often inspected and monitored using the magnetic flux leakage method. An inspection vehicle known as a "pig" is launched into the pipeline and conveyed along the pipe by the pressure of natural gas. The pig contains a magnetizer, an array of sensors and a microprocessor-based data acquisition system for logging data. This paper describes magnetic flux leakage (MFL) signal processing used for detecting mechanical damages during an in-line inspection. The overall approach employs noise removal and clustering technique. The proposed method is computationally efficient and can easily be implemented. Results are presented and verified by field tests from an application of the signal processing.

A Design of Sampling Inspection Plan for Single Manufacturing Production Process (제조생산공정의 경제적 샘플링 검사방식 설계)

  • 서경범;박명규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.48
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    • pp.269-277
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    • 1998
  • In this study, a traditional concept of sampling inspection plan for the quality assurance system is extended to a consideration of economic aspects in total production system by representing and analyzing the effects between proceding/succeeding production process including inspection. This approach recognizes that the decision to be made at one manufacturing process (or assembly process) determine not only the cost and the average outgoing quality level of that process but also the input parameters of the cost and the incoming quality to the succeeding process. By analyzing the effects of the average incoming and outgoing quality, manufacturing/assembly quality level and sampling inspection plan on the production system, mathematical models and solution technique to minimize the total production cost for a single product manufacturing system with specified average outgoing quality limit (AOQL) are suggested.

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Determinating Sensor Location for Guided-Wave-Based Long Range Pipeline Inspection (유도파 기반 장거리 파이프라인 검사를 위한 모니터링 센서의 위치결정)

  • Na Won-Bae;Ryu Yeon-Sun;Kim Jeong-Tae
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2006.04a
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    • pp.232-239
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    • 2006
  • Guided wave techniques have been used for pipeline inspection because of the long range inspection capability of guided waves. One of main concerns of these technique is how ones decide the axial interval of sensors when they are utilized for pipeline inspection. This question is related to the characteristic of cylindrical guided wave propagation, especially wave attenuation. Thus, attenuation of fundamental longitudinal guided wave propagating liquid-filled steel pipes is numerically investigated in the paper. Several liquids such as water, diesel oil, castor oil etc. are considered for the filing materials in the pipes. Sink is considered for numerical models for abandoning standing wave modes; hence, the attenuation dispersion curves become much simpler. Those attenuation calculations can be utilized for guided-wave-based nondestructive testing of pipelines when one inspects pipelines, using monitoring sensors, which are installed outside pipes.

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