• Journal of Korean Institute of Industrial Engineers
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• v.28 no.1
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• pp.57-62
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• 2002

The semiconductor industry has continuously been looking for the ways to improve yield and to reduce manufacturing cost. The layout modification approach, one of yield enhancement techniques, is applicable to all design styles, but it does not require any additional resources in terms of silicon area. The layout modification method for yield enhancement consists of making local variations in the layout of some layers in such a way that the critical area, and consequently the sensitivity of the layer to point defects, is reduced. Chen and Koren (1995) proposed a greedy algorithm that removes defect sensitive area using via moving, but it is easy to fall into a local minimum. In this paper, we present a via moving algorithm using simulated annealing and enhance yield by diminishing defect sensitive area. As a result, we could decrease the defect sensitive area effectively compared to the greedy algorithm presented by Chen and Koren. We expect that the proposed algorithm can make significant contributions on company profit through yield enhancement.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.4
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• pp.157-166
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• 2022

In the case of a die-casting process, defects that are difficult to confirm by visual inspection, such as shrinkage bubbles, may occur due to an error in maintaining a vacuum state. Since these casting defects are discovered during post-processing operations such as heat treatment or finishing work, they cannot be taken in advance at the casting time, which can cause a large number of defects. In this study, we propose an approach that can predict the occurrence of casting defects by defect type using machine learning technology based on casting parameter data collected from equipment in the die casting process in real time. Die-casting parameter data can basically be collected through the casting equipment controller. In order to perform classification analysis for predicting defects by defect type, labeling of casting parameters must be performed. In this study, first, the defective data set is separated by performing the primary clustering based on the total defect rate obtained during the post-processing. Second, the secondary cluster analysis is performed using the defect rate by type for the separated defect data set, and the labeling task is performed by defect type using the cluster analysis result. Finally, a classification learning model is created by collecting the entire labeled data set, and a real-time monitoring system for defect prediction using LabView and Python was implemented. When a defect is predicted, notification is performed so that the operator can cope with it, such as displaying on the monitoring screen and alarm notification.

• Korean Journal of Head & Neck Oncology
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• v.11 no.1
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• pp.47-55
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• 1995

A large lateral facial defects especially a through and through defect of the cheek remains as challenging field of reconstruction for the head and neck surgeons. Closure of these wounds is technically troublesome due to the magnitude and location of the soft tissue and skin defect, functional and aesthetic consideration. optimal cancer surveillance, and desire for good nourishment. Most traditional methods dealing with these defects, including split-thickness skin graft, local and regional flaps as well as musculocutaneous flaps have their limitations. We applied four different methods for these reconstruction in four cases. We utilized temporal muscle flap, forearm free flap and secondary healing for repair of mucosal defects, and medial base cervicopectoral flap, pectoralis major myocutaneous flap and cervicofacial flap for the reconstruction of external skin defects. In one case, both sides were reconstructed with single forearm free flap. In our experiences, secondary healing could be one of the useful method for mucosal repair in the defect between upper and lower gingivobuccal sulcus. However, forearm free flap was thought to be more ideal for the cases with mandibulectomy. For the external repair, the regional skin flap was considered to be superior to pectoralis major myocutaneous flap or forearm free flap especially on color matching.

• Journal of Korean Society for Quality Management
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• v.43 no.3
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• pp.273-288
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• 2015

Purpose: In this study, we apply environmental stress screening (ESS) to battle management system (BMS) of a tank and use the ESS profile based on production process data, guided by MIL-HDBK-781/344/2164. Methods: To optimize ESS Profile of the BMS of a tank, we estimate ESS model parameters (e.g., defect density, screening strength) using primary production failure reporting and corrective action system (FRACAS) data of military supply contract firm. Results: First, we collect the Primary production FRACAS data of military supply contract firm. Second, we compute curve fitting approach to find patent defect density and latent defect density using FRACAS data. Third, we solve the equation of Defect Density(patent defect density + latent defect density)($D_{IN}$) and Screening Strength(SS) Using second step data. As a result of analysis according to the order, we calculate $D_{IN}$(Temperature stress case : 74.02, Vibration stress : 10.252) and : SS(Temperature stress case : 0.4632, Vibration stress : 0.4142) and confirm the Condition II-D based on MIL-HDBK-344. According to Condition II-D, it is necessary to modify existing ESS profile through decreasing the $D_{IN}$ and increasing the SS. Conclusion: Identification of defect causes through ESS approach reduce defect densities for production. It provides feedback to a lessons-learned data base to avoid similar problems on next generation tank BMS.

• Journal of Chest Surgery
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• v.12 no.4
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• pp.429-433
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• 1979

Morgagni hernia is a rare condition of the congenital diaphragmatic hernia which Is located at the anteromedial portion of the diaphragm, and is located immediately posterior to the sternum. Its cause is considered by embryologic defect and the abdominal organs are passed through a defect. The incidence is predirected women over 50 years old. Its synonym is hernia of subcostosternal, retrosternal, parasternal, rectocostoxiphoid, anterior diaphragmatic or Larrey`s. This report presents a symptomatic Morgagni hernia of ten months old male child on whom the diagnosis was established and was operated at the Busan Gospel Hospital. This patient was admitted with the chief complaints of mild cyanosis, frequent upper respiratory infections and protrusion of the right lower anterior chest. Herniorrhaphy was performed through the upper abdominal midline incision, hernial contents of the omentum and the colon, and sac as noticed from the Larrey`s space measuring 4 x 2 cm. in diameter and oval in shape. Interrupted sutures without difficulty repaired the defect. The cyanosis was disappeared and the patient had uneventful course of post-operative period. The patient was discharged at 7th. postoperative day. This case presentation with a brief review of literatures is given.

• Transactions of Materials Processing
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• v.10 no.2
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• pp.151-159
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• 2001

Flow defect of a piston-pin for automobile parts is investigated in this study. In combined cold extrusion of piston-pin, lapping defect, which is a kind of flow defect, appears by the dead metal zone. This appearance evidently happens in products with a thin thickness to be pierced for the dimensional accuracy and the decrease of material loss. The flow defect that occurs in piston-pin has bad effects on the strength and the fatigue life of piston-pin. Therefore, it is important to predict and prevent defects in the early stage of process design. The best method that can prevent flow defect is removing or reducing dead metal zone through material flow control. The finite element simulations are applied to analyze the flow defect. This study proposes processes for preventing flow defect by removing dead metal zone. Then the results are compared with the experimental ones for verification. These FE simulation results are in good agreement with the experimental ones.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.183-188
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• 2005

Defect on the temporal area caused by, surgical ablation of a tumor or an infection should be reconstructed immediately to prevent potentially life-threatening complications such as meningitis and cerebrospinal fluid leakage. The defect on the temporal area usually presents as a typical 'cone-shape'. Successful reconstruction requires sufficient volume of well-vascularized soft tissue to cover the exposed bone and dura. From 1994 through 2003, the authors applied rectus abdominis free flap for the reconstruction of the temporal defect from 1994 through 2003. There were 10 patients with a mean age of 52.1 years. Of these 10 patients, external auditory canal cancer was present in four patients, temporal bone cancer in two, parotid gland cancer in one and three patients were reconstructed after debridement of infection(destructive chronic otitis media). All the free flaps survived, and flap-related complications did not occur. Compared to a local flap, the rectus abdominis free flap can provide sufficient volume of well-vascularized tissue to cover the large defect and can be well-tolerated during an adjuvant radiation therapy. The long and flat muscle can be easily molded to fit in to the 'cone-shape' temporal defect without dead space. It is also preferred because of the low donor site morbidity, a large skin island and an excellent vascular pedicle. Two-team approach without position change is possible. In conclusion, the authors think that rectus abdominis free flap should be considered as one of the most useful method for the reconstruction of a cone-shaped temporal defect.

• Korean Journal of Construction Engineering and Management
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• v.2 no.4 s.8
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• pp.69-79
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• 2001

Characteristics of Contactor's Defect Liability was too many discussed. But it's not clearly defined yet. Because recent Government Construction Projects are very complex and executed through long time, too many conflicts were appeared related to Contactor's Defect Liability. Therefore to analyse and to resolve the conflicts legal aspects of Contactor's Defect Liability stated in Civil Law and Government Contract Act was systematically compared. The result of this research is as follows : (1) Characteristic of Contactor's Defect must be regarded as a breach of Contract and be an incomplete contract implementation. (2) To decide the range of Damage, Characteristic of Defect must be regarded. (3) Contactor's Defect Liability must be effectual from the day of delivery. (4) Retainage must be added to secure the completion during the Contract Period and Defect Repairing Liability must be omitted in the Contract performance Security.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.6
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• pp.369-377
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• 2023

In the industrial manufacturing sector, quality control is pivotal for minimizing defect rates; inadequate management can result in additional costs and production delays. This study underscores the significance of detecting texture defects in manufactured goods and proposes a more precise defect detection technique. While the DFR(Deep Feature Reconstruction) model adopted an approach based on feature map amalgamation and reconstruction, it had inherent limitations. Consequently, we incorporated a new loss function using statistical methodologies, integrated a skip connection structure, and conducted parameter tuning to overcome constraints. When this enhanced model was applied to the texture category of the MVTec-AD dataset, it recorded a 2.3% higher Defect Segmentation AUC compared to previous methods, and the overall defect detection performance was improved. These findings attest to the significant contribution of the proposed method in defect detection through the reconstruction of feature map combinations.

• Journal of the Semiconductor & Display Technology
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• v.20 no.1
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• pp.113-117
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• 2021

A composite active layer was designed based on graphene quantum dots, which is a low-dimensional structure, and a heterogeneous active layer of graphene quantum dots was applied to the interfacial defect structure to overcome the limitations. Increasing to 1.5~3.5 wt % PVP GQD, Vf changed from 2.16 ~ 2.72 V. When negative deflection is applied to the lower electrode, electrons travel through the HfOx/ITO interface. The Al + ions are reduced and the device dominates at low resistance. In addition, as the PVP GQD concentration increased, the depth of the interfacial defect decreased, and the repetition of appropriate electrical properties was confirmed through Al and HfOx/ITO. The low interfacial defects help electrophoresis of Al+ ions to the PVP GQD layer and the HfOx thin film. A local electric field increase occurred, resulting in the breakage of the conductive filament in the defect.