• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.264-264
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• 2006

The nanoparticle-hydrogel complex as a new bone defect replacement matrix, which is composed of the nanoparticles for the sustained release of BMP and the hydrogel for filling the bone defect site and playing a role as a matrix where new bone can grow, is presented. In vivo evaluation of bone formation was characterized by soft X-ray, MT staining, and calcium assay, based on the rat calvarial critical size defect model. The effective bone regeneration was achieved by the BMP-2 loaded nanoparticles in fibrin gel, compare to bare fibrin gel, the nanoparticle-fibrin gel complex without BMP-2, or the BMP-2 in fibrin gel, in terms of the new bone area and the gray level in X-ray, the bone marrow are, and the calcium content in the initial defect site. These findings suggest that the BMP-2 loaded nanoparticle-fibrin gel complex can a promising candidate for a new bone defect replacement matrix.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.2
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• pp.259-264
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• 2009

High level quality control is required for mobile TFT-LCD modules which are frequently used for fine observation. However, quantitative quality control is difficult. Defect inspection using naked eyes makes irregular inspection results. This paper developed desk type defect inspection equipment for mobile TFT-LCD modules using the same inspection criterion with that of naked eyes. From experiments using this equipments, possibilities of standardization in defect inspection equipment for mobile TFT-LCD modules are presented.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.2059-2064
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• 2004

Texture analysis is an important role for automatic visual insfection. This paper presents an application of wavelet extension and Gray level co-occurrence matrix (GLCM) for detection of defect encountered in textured images. Texture characteristic in low quality images is not to easy task to perform caused by noise, low frequency and small dimension. In order to solve this problem, we have developed a procedure called wavelet image extension. Wavelet extension procedure is used to determine the frequency bands carrying the most information about the texture by decomposing images into multiple frequency bands and to form an image approximation with higher resolution. Thus, wavelet extension procedure offers the ability to robust feature extraction in images. Then the features are extracted from the co-occurrence matrices computed from the sub-bands which performed by partitioning the texture image into sub-window. In the detection part, Mahalanobis distance classifier is used to decide whether the test image is defective or non defective.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1380-1383
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• 2007

The secondary electron emission coefficient (${\gamma}$) of the cathode is an important factor for improving the discharge characteristics of AC-PDP, because of its close relationship to discharge voltage. In this experiment, we have investigated the electronic structure of the energy band in the MgO layer responsible for the high ${\gamma}$. We used three kinds of MgO pellet that have another component, and each MgO layers have been deposited by electron beam evaporation method. The work-functions of MgO layer have been investigated from their ion-induced secondary electron emission coefficient (${\gamma}$), respectively, using various ions with different ionization energies in a ${\gamma}-FIB$ (Focused Ion Beam) system. We have compared work-function with ${\gamma}-FIB$ system current signal for measurement defect energy level in MgO layer. MgO-A in the three types has lowest work-function value (4.12eV) and there are two defect energy levels.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05b
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• pp.30-33
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• 2001

Chemical mechanical polishing(CMP) process has been widely used to planarize dielectrics, which can apply to employed in integrated circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of free-defects in inter-level dielectrics (ILD). Especially, defects like micro-scratch lead to severe circuit failure, and affects yield. CMP slurries can contain particles exceeding $1{\mu}m$ size, which could cause micro-scratch on the wafer surface. The large particles in these slurries may be caused by particle agglomeration in slurry supply line. To reduce these defects, slurry filtration method has been recommended in oxide CMP. In this work, we have studied the effects of filtration and the defect trend as a function of polished wafer count using various filters in inter-metal dielectric(IMD)-CMP. The filter installation in CMP polisher could reduce defect after IMD-CMP. As a result of micro-scratches formation, it shows that slurry filter plays an important role in determining consumable pad lifetime.

• Korean Journal of Materials Research
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• v.11 no.1
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• pp.55-60
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• 2001

The effect of high energy B ion implantation and initial oxygen concentration upon defect formation and gettering of metallic impurities in Czochralski silicon wafer has been studied by applying DLTS( Deep Level Transient Spectroscopy), SIMS(Secondary ton Mass Spectroscopy), BMD (Bulk Micro-Defect) analysis and TEM(Transmission Electron Microscopy). DLTS results show the signal of the deep levels not only in as-implanted samples but also in low and high temperature annealed samples. Vacancy-related deep levels in as- implanted samples were changed to metallic impurities-related deep levels with increase of annealing temperature. In the case of high temperature anneal, by showing the lower deep level concentration with increase of initial oxygen concentration, high initial oxygen concentration seems to be more effective compared with the lower initial oxygen one.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1175-1176
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• 1993

This paper introduces a new model for forecasting groundwater level on the basis of analysing defect of finite element method. The new model is built with fuzzy sets and neural networks. It is convenient for use. We computed the groundwater level of one city in P. R. China with it and got a very satisfactory result. It can be popularized to corecast groundwater level of mine.

• Journal of the Korea Institute of Building Construction
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• v.11 no.3
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• pp.208-220
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• 2011

Recently, the arbitration system for defect disputes has been introduced to settle the disputes arising from defects in apartment buildings. However, the conciliation system did not reflect the current technical issues of defect disputes and the opinions of each party involved in the disputes. Moreover, it revealed more imperfections in the content and the process of the system itself. Therefore, this study aims to review the technical aspects of defect disputes, and suggest an alternative to the conventional conciliation system. This paper also discusses logical factors that can be addressed for the current subjective judgment. It is recommended that each party involved in the defect dispute build mutual trust in order to meet social needs, which is the underlying support for the revitalization of the institutional level.

• Korean Journal of Construction Engineering and Management
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• v.6 no.3 s.25
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• pp.128-134
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• 2005

Up to now, the various water proofing methods and materials have been developed. For the water proofing methods, poly-urethane membrane method is one of the commonly used and increase market share in water proofing industry due to it's many advantages. However, in spite of it's many advantages over other water proofing methods, water proofing defect occurs frequently. With this respect, the study investigate water proofing defect causes in roof water proofing. The study investigate 13 water proofing construction site in Sunchon city in oder to find urethane membrane defection causes and their type. As a results of the study, the followings are founded. 1) Among various water proofing defection causes, problems of water remain phenomenon due to surface horizontal level defect which occupy $25\;\%$ of total defect causes is the most commonly occur. 2) The second defect cause which occupy $15\;\%$ of total defect causes is the swell up phenomenon due to surface dry problem. For the prevention of water proofing defection in roof using urethane membrane, the followings are recommended. 1) Faultless surface treatment before using urethane membrane 2) Develop improved urethane membrane material 3) Improve urethane membrane construction technique

• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.328-336
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• 2005

Effects of surface defect distribution on flame instability during flame-surface interaction are experimentally investigated. To examine the chemical quenching phenomenon, we prepared thermally grown silicon oxide plates with well-defined defect density. Ion implantation was used to control the number of defects, i.e. oxygen vacancies. In an attempt to preferentially remove the oxygen atoms from silicon dioxide surface, argon ions with low energy level from 3keV to 5keV were irradiated at the incident angle of $60^{\circ}C$. Compositional and structural modification of $SiO_2$ induced by low-energy $Ar^+$ ion irradiation has been characterized by Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). The analysis shows that as the ion energy increases, the number of structural defect also increases and non-stoichiometric condition of $SiO_x(x{\le}2)$ plates is enhanced. From the quenching distance measurements, we found out that when the surface temperature is under $300^{\circ}C$, the quenching distance decreases on account of reduced heat loss; as the surface temperature increases over $300^{\circ}C$, however, quenching distance increases despite reduced heat loss effect. Such aberrant behavior is caused by heterogeneous chemical reaction between active radicals and surface defect sites. The higher defect density, the larger quenching distance. This results means that chemical quenching is governed by radical adsorption and can be parameterized by the oxygen vacancy density on the surface.