• Journal of Korea Society of Industrial Information Systems
• /
• v.19 no.6
• /
• pp.43-51
• /
• 2014

TFT-LCD image includes a defect of various properties. TFT-LCD image have a recognizable defects in the human inspector. On the other hand, it is difficult to detect defects that difference between the background and defect is very low. In this paper, we proposed sequentially detect algorithm from pixels included in the defect region to limited defects. And blob analysis methods using the blob size and gray difference are applied to the defect candidate image. Finally, we detect an accurate defect blob to distinguish the noise. The experimental results show that the proposed method finds the various defects reliably.

• Journal of Mechanical Science and Technology
• /
• v.14 no.5
• /
• pp.530-536
• /
• 2000

In this paper, the influence of several factors such as hardness, internal defect and non-propagating crack on fatigue limits was investigated with three kinds of ductile iron specimens. From the experimental results the fatigue limits were examined in relation with hardness and tensile strength in case of high strength specimens under austempering treatment; in consequence the marked improvement of fatigue limits were not showed. The maximum defect size was an important factor to predict and to evaluate the fatigue limits of ductile irons. And, the quantitative relationship between the fatigue limits$({\sigma}_w)$ and the maximum defect sizes $(\sqrt{area}_{max})$ was expressed as ${\sigma}_w^n{\cdot}{\sqrt{area}}_{max}=C_2$. Also, it was possible to explain the difference for the fatigue limits in three ductile irons by introduction of the non-propagating crack rates.

• Journal of the Optical Society of Korea
• /
• v.19 no.6
• /
• pp.619-628
• /
• 2015

In this paper, we consider a method for estimating a stripe-type defect and the reconstruction of a defect-free L/S type mask used in lithography. Comparing diffraction patterns of defected and defect-free masks, we derive equations for the estimation of the location and size of the defect. We construct an analytical model for this problem and derive closed form equations to determine the location and size using phase retrieval problem solving techniques. Consequently, we develop an algorithm that determines a defect-free mask pattern. An example shows the validity of the equations.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.30 no.1
• /
• pp.13-19
• /
• 2010

In this paper, we study a new estimation system for the prediction of steam generator tube defects. In the previous research works, defect size estimators were independently designed for each defect types in order to estimate the defect size. As a result, the structure of estimation system is rather complex and the estimation performance gets worse if the classification performance is degraded for some reason. This paper studies a new estimation system that does not require the classification of defect types. Although the previous works are expected to achieve much better estimation performance than the proposed system since it uses the estimator specialized in each defect, the performance difference is not so large. Therefore, it is expected that the proposed estimator can be effectively used for the case where the defect type classification is imperfect.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.38 no.4
• /
• pp.266-276
• /
• 2001

Due to the rapid development of semiconductor technology, the complexity of VLSI circuits has heavily increased. With the increased densities of integrated circuits, several different types of faults can occur Thus, testing such circuits is becoming a sever problem. Delay testing can detect system timing failures caused by delay faults. However, the conventional delay fault coverage in terms of the number of detected faults may not be an effective measure of delay testing because, unlike a stuck-at-faults, the impact of a delay fault is dependent on its delay defect size rather than on its existence. Thus, the effectiveness of delay testing is dependent on the propagation delay of the path to be tested, the delay defect size, and the system clock interval. This paper proposes a new delay defect fault coverage that considers both propagation delay of the path to be tested and additional delay defect size. And the relationship between delay defect fault coverage and defect level is analyzed.

• Journal of the Korean institute of surface engineering
• /
• v.49 no.2
• /
• pp.111-118
• /
• 2016

A method to quantitatively analyze the defects formed by the hydrogen evolution during electroplating was suggested based on the theoretical approach of the small angle neutron scattering technique. In case of trivalent chrome layers, an isolated defect size due to the hydrogen evolution was about 40 nm. Direct and pulse plating conditions gave the average defect size of about 4.9 and $4.5{\mu}m$ with rod or calabash shape, respectively. Current density change of the pulse plating from $1.5A/dm^2$ to $2.0A/dm^2$ enlarged the average defect size from 3.3 to $7.8{\mu}m$. The defect morphology like rod or calabash was originated by inter-connecting the isolated defects. Small angle neutron scattering was useful to quantitatively evaluate defect morphology of the deposit.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.6 no.1
• /
• pp.45-50
• /
• 1997

It is not clearly known how surface defects or inclusions of a medium carbon steel affect a fatigue strength. In this study, we used SM35C specimens with spheroidized cementite structure to eliminate dependence of micro structure of fatigue crack. The investigation was carried out by behavior of crack closure at non-propagation crack and effect of the fatigue limit according to the artificial defects size. Experimental findings are obtained as follows : (1) Fatigue crack initiation point of medium carbon steel with spheroidized cementite structure is at the surface defects. (2) Non-propagating crack length of smooth specimen is equal to the critical size of defect. (3) Considering the opening and closure behavior of fatigue crack, the defect shape results in various crack opening displacement, while it does not affects the fatigue limit level of medium carbon steel with spheroidized cementite structure. (4) The critical length of the non-propagation crack of smooth specimen is the same as critical size of defect in transient area which determines threshold condition in steel with spheroidized cementite structure.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.41 no.8
• /
• pp.69-78
• /
• 2004

In this paper, we estimated the exact software defect density to build up a suitable model that is closely related to the size of module in the probability model proposed by MD (Malaiya and Denton). To put it concretely, we predict that the software defect density using some practical data sets that are the outcomes from the system test performed our three projects for the types of distribution (exponential and geometric), per a unit of module, and the size of source line that have been recommended by KLOC(kilo-line-of-code). Then, we make comparison between our proposed defect density model and those examined real data.

• Structural Engineering and Mechanics
• /
• v.84 no.6
• /
• pp.799-811
• /
• 2022

Adhesive bonding has seen rapid development in recent years, with emphasis to composite patch repairing processes of geometric defects in aeronautical structures. However, its use is still limited given its low resistance to climatic conditions and requirement of specialized labor to avoid fabrication induced defects, such as air bubbles, cracks, and cavities. This work aims to numerically analyze, by the finite element method, the failure behavior of a damaged plate, in the form of a bonding defect, and repaired by an adhesively bonded composite patch. The position and size of the defect were studied. The results of the numerical analysis clearly showed that the position of the defect in the adhesive layer has a large effect on the value of J-Integral. The reduction in the value of J-Integral is also related to the composite stacking sequence which, according to the mechanical properties of the ply, provides better load transfer from the plate to the repair piece through the adhesive. In addition, the increase in the applied load significantly affects the value of the J-Integral at the crack tip in the presence of a bonding defect, even for small dimensions, by reducing the load transfer.

• Archives of Reconstructive Microsurgery
• /
• v.25 no.1
• /
• pp.7-11
• /
• 2016

Purpose: In recent decades, amputation is still recommended for patients with extensive lower extremity wounds requiring coverage. Although the feet contribute relatively little to total body surface area, they are essential organ for ambulation, and a high mortality rate after amputation has been reported. We report on 10 challenging cases of a mangled foot which was reconstructed using an anterolateral thigh (ALT) free flap, and analyze the advantages and disadvantages of this technique. Materials and Methods: This retrospective study was conducted on 10 patients who underwent reconstructive surgery on a foot. Patients' charts were reviewed for age, sex, causes, defect size and site, flap size and type, flap type, and complications. Cases with a defect size of > $100cm^2$ were included. Results: Seven of the 10 patients were male, and overall mean age was 38.5 years (range, 22 to 61 years). Mean defect size was $179.6cm^2$ (range, 104 to $330cm^2$), and mean flap size was $193cm^2$ (range, 120 to $408cm^2$). Three cases were reconstructed with a musculocutaneous free flap and seven cases were reconstructed with a fasciocutaneous free flap. There were two occurrences of local wound complication. All ten flaps survived well, however five patients underwent a debulking procedure to reduce flap volume. Conclusion: Reconstruction of a near completely degloved soft tissue defect or a wide defect containing two or more surfaces of extremity with an ALT free flap was performed. The purpose of this case study is to report on free tissue transfer using the ALT flap for salvage of the lower extremity.