• Title/Summary/Keyword: Detection of defects

Search Result 759, Processing Time 0.026 seconds

Design of Optimized pRBFNNs-based Face Recognition Algorithm Using Two-dimensional Image and ASM Algorithm (최적 pRBFNNs 패턴분류기 기반 2차원 영상과 ASM 알고리즘을 이용한 얼굴인식 알고리즘 설계)

  • Oh, Sung-Kwun;Ma, Chang-Min;Yoo, Sung-Hoon
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.21 no.6
    • /
    • pp.749-754
    • /
    • 2011
  • In this study, we propose the design of optimized pRBFNNs-based face recognition system using two-dimensional Image and ASM algorithm. usually the existing 2 dimensional face recognition methods have the effects of the scale change of the image, position variation or the backgrounds of an image. In this paper, the face region information obtained from the detected face region is used for the compensation of these defects. In this paper, we use a CCD camera to obtain a picture frame directly. By using histogram equalization method, we can partially enhance the distorted image influenced by natural as well as artificial illumination. AdaBoost algorithm is used for the detection of face image between face and non-face image area. We can butt up personal profile by extracting the both face contour and shape using ASM(Active Shape Model) and then reduce dimension of image data using PCA. The proposed pRBFNNs consists of three functional modules such as the condition part, the conclusion part, and the inference part. In the condition part of fuzzy rules, input space is partitioned with Fuzzy C-Means clustering. In the conclusion part of rules, the connection weight of RBFNNs is represented as three kinds of polynomials such as constant, linear, and quadratic. The essential design parameters (including learning rate, momentum coefficient and fuzzification coefficient) of the networks are optimized by means of Differential Evolution. The proposed pRBFNNs are applied to real-time face image database and then demonstrated from viewpoint of the output performance and recognition rate.

A Development of Welding Information Management and Defect Inspection Platform based on Artificial Intelligent for Shipbuilding and Maritime Industry (인공지능 기반 조선해양 용접 품질 정보 관리 및 결함 검사 플랫폼 개발)

  • Hwang, Hun-Gyu;Kim, Bae-Sung;Woo, Yun-Tae;Yoon, Young-Wook;Shin, Sung-chul;Oh, Sang-jin
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.25 no.2
    • /
    • pp.193-201
    • /
    • 2021
  • The welding has a high proportion of the production and drying of ships or offshore plants. Non-destructive testing is carried out to verify the quality of welds in Korea, radiography test (RT) is mainly used. Currently, most shipyards adopt analog-type techniques to print the films through the shoot of welding parts. Therefore, the time required from radiography test to pass or fail judgment is long and complex, and is being manually carried out by qualified inspectors. To improve this problem, this paper covers a platform for scanning and digitalizing RT films occurring in shipyards with high resolution, accumulating them in management servers, and applying artificial intelligence (AI) technology to detect welding defects. To do this, we describe the process of designing and developing RT film scanning equipment, welding inspection information integrated management platform, fault reading algorithms, visualization software, and testing and verification of each developed element in conjunction.

Development of A-ABR System Using a Microprocessor (마이크로프로세서를 이용한 자동청력검사 시스템 개발)

  • Noh, Hyung-Wook;Lee, Tak-Hyung;Kim, Nam-Hyun;Kim, Soo-Chan;Cha, Eun-Jong;Kim, Deok-Won
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.46 no.2
    • /
    • pp.15-21
    • /
    • 2009
  • Hearing loss is one of the most common birth defects among infants. Most of hearing-impaired children are not diagnosed until 1 to 3 years of age - which is too late for the critical period (6 month) for normal speech and language development. If a hearing impairment is identified and treated in its early stage, child's speech and language skills could be comparable to his or her normal-hearing peers. For these reasons, hearing screening at birth and throughout childhood is extremely important. ABR (Auditory brain-stem response) is nowadays one of the most reliable diagnostic tools in the early detection of hearing impairment. In this study, we have developed the system that automatically detects if there is hearing impairment or not for infants or children. For future studies, it will be developed as a portable system to be able to take a measurement not only in sound proof room but also in nursery for neonates.

A Study on the shelf-life of IR screening smoke launcher grenade (적외선 차장 연막유탄 신뢰도 및 저장수명 연구)

  • Lee, Jongchan;Lee, Junhyuk;Jung, Hyunsuk
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.4
    • /
    • pp.437-445
    • /
    • 2020
  • Smoke grenades are the primary means of protection used by tanks to disrupt enemy detection systems. Such smoke grenades are a critical factor that determines the survival of tanks in the engagement of ground weapon systems, but it can only be used once. Owing to its destructive property, the performance and safety of the smoke grenade cannot be confirmed prior to use. Therefore, the reliability of smoke grenades can be evaluated through various tests during the storage period. This paper presents the results of estimating the reliability and shelf life of IR screening smoke grenade launchers based on the result of the Ammunition Stockpile Reliability Program conducted in 2019. Among the smoke grenade launcher lots currently stored, 16 lots and samples were selected for each year of manufacture and tested. The reliability and shelf life were estimated by examining the number of defects and the change in quality characteristics of each test item. The results of this study can be used to assess the reliability of the smoke grenade launchers and to improve the quality of manufacturing sites.

Development of an abnormal road object recognition model based on deep learning (딥러닝 기반 불량노면 객체 인식 모델 개발)

  • Choi, Mi-Hyeong;Woo, Je-Seung;Hong, Sun-Gi;Park, Jun-Mo
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.22 no.4
    • /
    • pp.149-155
    • /
    • 2021
  • In this study, we intend to develop a defective road surface object recognition model that automatically detects road surface defects that restrict the movement of the transportation handicapped using electric mobile devices with deep learning. For this purpose, road surface information was collected from the pedestrian and running routes where the electric mobility aid device is expected to move in five areas within the city of Busan. For data, images were collected by dividing the road surface and surroundings into objects constituting the surroundings. A series of recognition items such as the detection of breakage levels of sidewalk blocks were defined by classifying according to the degree of impeding the movement of the transportation handicapped in traffic from the collected data. A road surface object recognition deep learning model was implemented. In the final stage of the study, the performance verification process of a deep learning model that automatically detects defective road surface objects through model learning and validation after processing, refining, and annotation of image data separated and collected in units of objects through actual driving. proceeded.

Intrawound Vancomycin Powder Application for Preventing Surgical Site Infection Following Cranioplasty

  • Seong Bin Youn;Gyojun Hwang;Hyun-Gon Kim;Jae Seong Kang;Hyung Cheol Kim;Sung Han Oh;Mi-Kyung Kim;Bong Sub Chung;Jong Kook Rhim;Seung Hun Sheen
    • Journal of Korean Neurosurgical Society
    • /
    • v.66 no.5
    • /
    • pp.536-542
    • /
    • 2023
  • Objective : Surgical site infection is the most detrimental complication following cranioplasty. In other surgical fields, intrawound vancomycin powder application has been introduced to prevent surgical site infection and is widely used based on results in multiple studies. This study evaluated the effect of intrawound vancomycin powder in cranioplasty compared with the conventional method without topical antibiotics. Methods : This retrospective study included 580 patients with skull defects who underwent cranioplasty between August 1, 1998 and December 31, 2021. The conventional method was used in 475 (81.9%; conventional group) and vancomycin powder (1 g) was applied on the dura mater and bone flap in 105 patients (18.1%; vancomycin powder group). Surgical site infection was defined as infection of the incision, organ, or space that occurred after cranioplasty. Surgical site infection within 1-year surveillance period was compared between the conventional and vancomycin powder groups with logistic regression analysis. Penalized likelihood estimation method was used in logistic regression to deal with zero events. All local and systemic adverse events associated with topical vancomycin application were also evaluated. Results : Surgical site infection occurred in 31 patients (5.3%) and all were observed in the conventional group. The median time between cranioplasty and detection of surgical site infection was 13 days (range, 4-333). Staphylococci were the most common organisms and identified in 25 (80.6%) of 31 cases with surgical site infections. The surgical site infection rate in the vancomycin powder group (0/105, 0.0%) was significantly lower than that in the conventional group (31/475, 6.5%; crude odds ratio [OR], 0.067; 95% confidence interval [CI], 0.006-0.762; adjusted OR, 0.068; 95% CI, 0.006-0.731; p=0.026). No adverse events associated with intrawound vancomycin powder were observed during the follow-up. Conclusion : Intrawound vancomycin powder effectively prevented surgical site infections following cranioplasty without local or systemic adverse events. Our results suggest that intrawound vancomycin powder is an effective and safe strategy for patients undergoing cranioplasty.

A Novel COMP Gene Mutation in a Korean Kindred with Multiple Epiphyseal Dysplasia

  • Ko, Jung-Min;Kwack, Kyu-Sung;Baek, Kum-Nyeo;Cho, Dae-Yeon;Kim, Hyon-Ju
    • Journal of Genetic Medicine
    • /
    • v.6 no.1
    • /
    • pp.81-86
    • /
    • 2009
  • Multiple epiphyseal dysplasia (MED) is a clinically and genetically heterogeneous chondroplasia, characterized by delayed development of the ossification centers and, deformities of the extremities that involve only the epiphysis and result in mild short stature. Mutations in the cartilage oligomeric matrix protein (COMP) gene are most commonly found, and most of the mutations are located in the calmodulin-like repeats and the C-terminal domain. We report a Korean kindred of 12 family members with MED in four generations who were found to have a novel mutation in the COMP gene. A pedigree showed early onset osteoarthritis requiring arthroplasty that was an autosomal dominant inherited trait. Radiological examinations demonstrated the presence of osteochondral defects in the medial femoral condyles, and the knee and hip joints showed variable degrees of precocious degenerative changes. Mutation analysis of the COMP gene in the proband and five other affected family members identified a novel missense mutation, c.1280G>C (p.Gly427Ala) in exon 12, which was not found in three unaffected family members. Direct sequencing of the COMP gene may yield pathogenic mutations in dominantly inherited MED cases, and may provide opportunities of carrier detection among high-risk family members, leading to genetic counseling for early diagnosis and intervention before the onset of complications.

  • PDF

Study on Signal Processing in Eddy Current Testing for Defects in Spline Gear (스플라인 기어부 결함의 와전류검사 신호처리에 관한 연구)

  • Lee, Jae Ho;Park, Tae Sung;Park, Ik Keun
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.36 no.3
    • /
    • pp.195-201
    • /
    • 2016
  • Eddy current testing (ECT) is commonly applied for the inspection of automated production lines of metallic products, because it has a high inspection speed and a reasonable price. When ECT is applied for the inspection of a metallic object having an uneven target surface, such as the spline gear of a spline shaft, it is difficult to distinguish between the original signal obtained from the sensor and the signal generated by a defect because of the relatively large surface signals having similar frequency distributions. To facilitate the detection of defect signals from the spline gear, implementation of high-order filters is essential, so that the fault signals can be distinguished from the surrounding noise signals, and simultaneously, the pass-band of the filter can be adjusted according to the status of each production line and the object to be inspected. We will examine the infinite impulse filters (IIR filters) available for implementing an advanced filter for ECT, and attempt to detect the flaw signals through optimization of system design parameters for detecting the signals at the system level.

Creation of Crack BIM in Bridge Deck and Development of BIM-FEM Interoperability Algorithm (교량 바닥판의 균열 BIM 생성 및 BIM-FEM 상호 연계 알고리즘 개발)

  • Yang, Dahyeon;Lee, Min-Jin;An, Hyojoon;Jung, Hyun-Jin;Lee, Jong-Han
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.43 no.6
    • /
    • pp.689-693
    • /
    • 2023
  • Domestic bridges with a service life of more than 30 years are expected to account for approximately 54% of all bridges within the next 10 years. As bridges rapidly deteriorate, it is necessary to establish an appropriate maintenance plan. Recent domestic and international research have focused on the integration of BIM to digitize bridge maintenance information and then enhance accessibility and usability of the information. Accordingly, this study developed a BIM-FEM interoperability algorithm for bridge decks to convert maintenance information into data and efficiently manage the history of maintenance. After creating an initial crack BIM based on an exterior damage map, bridge specification and damage information were linked to a numerical analysis that performs damage analysis considering damage scenarios and design loads. The spread of cracks obtained from the analysis results were updated into the BIM. Based on the damage spread information on the BIM, an automated technology was also developed to assess both the current and future condition ratings of the bridge deck. This approach can enable an efficient maintenance of the deck using the history data from bridge inspection and diagnosis as well as future information on cracks and defects. The expected early detection and prevention would ultimately improve the lifespan and safety of bridges.

Quantitative EC Signal Analysis on the Axial Notch Cracks of the SG Tubes (SG Tube 축방향 노치 균열의 정량적 EC 신호평가)

  • Min, Kyong-Mahn;Park, Jung-Am;Shin, Ki-Seok;Kim, In-Chul
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.29 no.4
    • /
    • pp.374-382
    • /
    • 2009
  • Steam generator(SG) tube, as a barrier isolating primary to the secondary coolant system of nuclear power plants(NPP), must maintain the structural integrity far the public safety and its efficient power generation capacity. And SG tubes bearing defects must be timely detected and taken repair measures if needed. For the accomplishment of these objectives, SG tubes have been periodically examined by eddy current testing(ECT) on the basis of administrative notices and intensified SG management program(SGMP). Stress corrosion cracking(SCC) on the SG tubes is not easily detected and even missed since it has lower signal amplitude and other disturbing factors against its detection. However once SCC is developed, that can cause detrimental affects to the SG tubes due to its rapid propagation rate. Accordingly SCC is categorized as prime damage mechanism challenging the soundness of the SG tubes. In this study, reproduced EDM notch specimens are examined for the detectability and quantitative characterization of the axial ODSCC by +PT MRPC probe, containing pancake, +PT and shielded pancake coils apart in a single plane around the circumference. The results of this study are assumed to be applicable fur providing key information of engineering evaluation of SCC and improvement of confidence level of ECT on SG tubes.