• Journal of Korean Society of Steel Construction
• /
• v.11 no.1 s.38
• /
• pp.1-11
• /
• 1999

The aim of this study is to construct a machine vision monitoring system for an automatic visual inspection of weld joint in steel structure. An image processing algorithm for a visual weld defects detection on weld bead is developed using the intensity image. An optic system for getting four intensity images was set as a fixed camera position and four different illumination directions. The input images were thresholded and segmented after a suitable preprocessing and the features of each region were defined and calculated. The features were used in the detection and the classification of the visual weld defects. It is confirmed that the developed algorithm can detect weld defects that could not be detected by previously developed techniques. The recognized results were evaluated and compared to expert inspectors' results.

• Journal of Mechanical Science and Technology
• /
• v.18 no.1
• /
• pp.65-73
• /
• 2004

Composites are a material class for which nondestructive material property characterization is as important as flaw detection. Laminates of fiber reinforced composites often possess strong in-plane elastic anisotropy attributable to the specific fiber orientation and layup sequence when waves are propagating in the thickness direction of composite laminates. So the layup orientation greatly influences its properties in a composite laminate. It could result in the part being .ejected and discarded if the layup orientation of a ply is misaligned. A nondestructive technique would be very beneficial, which could be used to test the part after curing and requires less time than the optical test. Therefore a ply-by-ply vector decomposition model has been developed, simplified, and implemented for composite laminates fabricated from unidirectional plies. This model decomposes the transmission of a linearly polarized ultrasound wave into orthogonal components through each ply of a laminate. Also in order to develop these methods into practical inspection tools, motorized system have been developed for different measurement modalities for acquiring ultrasonic signals as a function of in-plane angle. It is found that high probability shows between the model and tests developed in characterizing cured layups of the laminates.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.41 no.3
• /
• pp.138-144
• /
• 2018

Inventory inspection is an important task to eliminate the inconsistency between real assets and inventory management systems, and it is performed periodically at the site. In the case of a large-sized property, it is mainly managed in an outdoor workshop or a warehouse. However, due to the large area of the outdoor area, it is relatively difficult to identify the quantity and location of the property and is also vulnerable to theft. To solve this problem, we proposed a method and system for performing a warehouse inventory inspection using an unmanned aerial vehicle (UAV) and Bluetooth low energy (BLE) beacons. The proposed method has the following advantages. First of all, if we carry out inventory inspection by utilizing UAV, we can minimize user's effort compared to existing methods. The method of recognizing the asset by attaching the BLE beacon is more costly than using the existing RFID technology, but it is advantageous because the recognition distance is increased and the battery life of the tag is drastically increased. We also designed a BLE beacon reader for the system and implemented a prototype to show the feasibility of the proposed system. The prototype is based on Genuino 101, which is a kind of arduino, and adds HM-10 and Neo-6m modules to provide Bluetooth and GPS functions. The BLE beacon reader was tested in outdoor, and attached in drone. We also developed an inventory checking system based on the web to display results of inventory checking. The proposed approach enables the users to automate the operation of inventory checking on an outdoor warehouse.

• Journal of Information Technology Services
• /
• v.11 no.4
• /
• pp.153-170
• /
• 2012

When companies or institutes manage data, in order to utilize it as useful resources for decision-making, it is essential to offer precise and reliable data. While most small and medium-sized enterprises and public institutes have been investing a great amount of money in management and maintenance of their data systems, the investment in data management has been inadequate. When public institutions establish their data systems, inspection has been constantly carried out on the data systems in order to improve safety and effectiveness. However, their capabilities in improving the quality of data have been insufficient. This study develops an automatic tool to diagnose the quality of data in a way to diagnose the data quality condition of the inspected institute quantitatively at the stage of design and closure by inspecting the data system and proves its practicality by applying the automatic tool to inspection. As a means to diagnose the quality, this study categorizes, in the aspect of quality characteristics, the items that may be improved through diagnosis at the stage of design, the early stage of establishing the data system and the measurement items by the quality index regarding measurable data values at the stage of establishment and operation. The study presents a way of quantitative measurement regarding the data structures and data values by concretizing the measurement items by quality index in a function of the automatic tool program. Also, the practicality of the tool is proved by applying the tool in the inspection field. As a result, the areas which the institute should improve are reported objectively through a complete enumeration survey on the diagnosed items and the indicators for quality improvement are presented quantitatively by presenting the quality condition quantitatively.

• The Journal of Korean Institute for Practical Engineering Education
• /
• v.3 no.1
• /
• pp.143-148
• /
• 2011

In this study, the damage to the bridge structure such as the crack and water leakage was assessed due to the increase of the vehicle load and traffic on the roads. In order to make this into the database, as a part of the automation system development for the bridge maintenance, the students themselves designed and developed their own inspection robotic system based on the idea of robots currently being developed overseas. Its field testing was conducted and its applicability assessed. During the design and fabrication, its connection to the details of the unit course taken in the undergraduate level was focused. In terms of new product development, the field application was possible due to the support of the academic-industrial cooperation firms. Furthermore, through the survey of the students, the improvements in the practical skills of the students who participated in this development process was affirmed.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.2
• /
• pp.335-341
• /
• 2017

This paper proposes an image-processing algorithm for inspecting double-cut defects in the motor shaft manufacturing process. The algorithm consists of extracting the outline using the brightness of the image, obtaining a binarized boundary graph using the extracted outline, and determining the defects from the graph. Defects in which two cut surfaces are separated are considered type 1 defects, and those in which two cut surfaces are connected are defined as type 2 defects. In an actual manufacturing process, 112 good samples and 44 defective samples (34 type 1 defects and 10 type 2 defects) were collected and used to verify the algorithm. The samples were judged with 100% accuracy for both type 1 and type 2 defects. The algorithm will be used in the field after securing reliability for various samples.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.27 no.5
• /
• pp.84-88
• /
• 2023

This study proposes an automated tilt measurement method using point cloud for buildings. The proposed method consists of two main steps: 1) exterior wall plane extraction, and 2) edge estimation and angle calculation. To validate the performance of the proposed method, the algorithm is applied to a target building, of which the estimated tilt values are compared with those obtained from a total station, a commonly used tool for tilt measurement. The result shows that most estimated tilt values are within the maximum and minimum ranges of the total station measurement, suggesting that the proposed algorithm provides sufficient measurement accuracy. Furthermore, the proposed method is shown to be automated and reliable as well as free from human-induced errors compared to the total station.

• The Research Journal of the Costume Culture
• /
• v.6 no.4
• /
• pp.149-161
• /
• 1998

The purpose of this study was to present the effective activation of apparel CAD system and for this, the investigation of actual condition of CAD using companies and comparative inspection with the advanced study were carefully considered. The results were as follows : 1. The investigation result of the system using enterprises is that the direct effect from the operation of the CAD system after its introduction was the promptness, ad the indirect effect of it was the growth of operation level and operating reliance. 2. The problem originated from the system was the uncertainty of employer effectiveness and the financing source for it when introduced, and the lack of consciousness of it when operated. 3. The using level in pattern manufacturing function was lower than that in grading and marking. Therefore, as the full automation in CAD system is a part of CIM construction and the direction to which apparel companies should go, a firmly connected system between management & the persons in charge in apparel companies, facility supplying companies, universities & other educational institutes, and the Government should be duly constructed first of all n order to achieve this aim.

• Journal of Biomedical Engineering Research
• /
• v.12 no.2
• /
• pp.89-98
• /
• 1991

This study is concerned on the automation for cell diagnosis which has better objectivity and speed of test than human beings. Diagnosis is on the basis of shape change of abnormal Cells. Used parameters are nucleus area, nucleus perimeter, nucleus shape, cytoplasm area, nucleus/cytoplsm ratio, which was obtained using image processing technics. A new mode method is proposed on the automatic threshold selection for superior process time compared with Otsu's. Contour of the cytoplasm of abnormal cell is obtained using me- dian filter and sorel operator. The mask to get only original shape of abnormal cells is formed uslng the contour filling algorithm. In the result the normal cells are separated from the abnormal cells and the abnormal cells can be distinguished through screwing of abnormal cell's image with reference data to judge abnormal cells. Owing to this study the number of inspections which the pathologists should examine will be decreased and the time for inspection will be shortened.

• International Journal of Control, Automation, and Systems
• /
• v.6 no.6
• /
• pp.828-835
• /
• 2008

We present a novel method for eye location by means of a two-level classifier scheme. Locating the eye by machine-inspection of an image or video is an important problem for Computer Vision and is of particular value to applications in biomedical imaging. Our method aims to overcome the significant challenge of an eye-location that is able to maintain high accuracy by disregarding highly variable changes in the environment. A first level of computational analysis processes this image context. This is followed by object detection by means of a two-class discrimination classifier(second algorithmic level).We have tested our eye location system using FERET and BioID database. We compare the performance of two-level classifier with that of non-level classifier, and found it's better performance.