• Journal of Labour Economics
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• v.43 no.1
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• pp.59-91
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• 2020

The recent reform of child care policy is to give priority to double-income households in the use of childcare facilities. This study analyzed the effect of the use of childcare facilities on the employment of married women under the on-going reform. Using the data from the 19th and 21st wave of the Korean Labor and Income Study, the marginal treatment effect (MTE) analysis method was used to eliminate the selection bias in which the sub-population targeted for policy is determined according to the priority when childcare demand exceeds supply. The study finds that the employment effect of married women who use childcare facilities does not differ statistically from the employment effect of married women who do not use childcare facilities.

• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.191-194
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• 2009

Porous alumina prepared by anodization has been widely studied since it shows very regular nanostructures at inexpensive prices. In this article, porous alumina is obtained by anodization of aluminum in the oxalic acid. After the first formed oxide is selectively removed from the aluminum substrate, the hexagonal nanostructures on the fresh aluminum are converted to nanodots by the second anodization in boric acid. Nanodots are arrayed in the convex of the hexagonal nanostructures. The optimization condition for the fabrication of nanodots with a height of 20 nm is investigated in detail. Subsequently, a gold film is deposited on the nanodots, resulting in the formation of gold nanodots arrays which are probably interesting substrate for biosensor applications.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.376-381
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• 2008

The deactivation of $V/TiO_2$ catalyst used in SCR (Selective Catalytic Reduction) using ammonia as a reductant to remove the nitrogen oxides (NOx) in the exhaust gas from fired power plant has been studied. The activity and surface area of the catalyst (Used-cat) which was exposed to the exhaust gas for long period have considerably decreased. The characterizations of these SCR catalysts were performed by XRD, FT-IR, FE-SEM, and IC/ICP. The crystal structure of $TiO_2$ both fresh and used catalyst has not been changed. However, $(NH_4)HSO_4$ deposited on the used catalyst surface verified from FT-IR, FE-SEM, and IC/ICP analysis. Moreover, the durability of $SO_2$ was increased by diminishing sulfate ($SO_4^{-2}$)f form.

• Korean Journal of Head & Neck Oncology
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• v.28 no.1
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• pp.8-11
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• 2012

배경 및 목적 : 섬유소 응고제(fibrin sealants)는 다양한 두경부수술에서 지혈목적으로 사용되고 있다. 본 연구의 목적은 배액관을 삽입하지 않는 갑상선 수술에서 섬유소 응고제의 효용성과 안정성을 알아보고자 하였다. 재료 및 방법 : 최근 1년간 108명의 갑상선 수술환자 중에서 수술 후 배액관의 삽입없이 수술을 받은 103명의 환자를 대상으로 하여 임상적인 특징을 분석하였다. 결과 : 103명의 대상환자 중에서 남성은 16예, 여성은 87예였다. 대상환자의 평균연령은 $46.7{\pm}13.0$세였고, 연령분포는 17세에서 72세였다. 갑상선 종물의 평균크기는 $2.08{\pm}1.61cm$였고, 종물의 크기는 최소 0.2cm에서 최대 10.0cm까지의 분포를 보였다. 수술에는 갑상선 엽절제술이 5예, 갑상선반절제술이 41예, 아갑상선 절제술이 8예, 갑상선 전절제술이 6예, 갑상선 전절제술과 중심경부림프절 절제술이 37예, 갑상선 전절제술과 선택적경부림프절 절제술이 6예가 있었다. 수술 후 합병증은 11예(10.6%)에서 발생하였고, 발생한 합병증으로는 장액성종창이 3예, 혈종이 1예, 일측성 성대마비가 3예, 저칼슘혈증이 4예 있었다. 성대마비는 수술 후 3개월 이내에 모두 호전되었고, 장액성 종창은 반복적인 세침흡인으로 호전되었다. 1예의 혈종은 지연성으로 발생하였고, 수술 후 5일째에 수술을 통해 제거하였다. 결론 : 이러한 결과에 근거하여 갑상선 수술에서 섬유소 응고제의 사용은 다양한 갑상선 수술에서 효과적인 지혈과 함께 안전하게 사용될 수 있으며, 배액관의 삽입을 감소시켜 줄 수 있을 것으로 생각된다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.10
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• pp.2209-2216
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• 2011

In this paper, we design a 32-bit eFuse OTP memory for PMICs using MagnaChip's $0.18{\mu}m$ process. We solve a problem of an electrical shortage between an eFuse link and the VSS of a p-substrate in programming by placing an n-well under the eFuse link. Also, we propose a WL driver circuit which activates the RWL (read word-line) or WWL (write word-line) of a dual-port eFuse OTP memory cell selectively when a decoded WERP (WL enable for read or program) signal is inputted to the eFuse OTP memory directly. Furthermore, we reduce the layout area of the control circuit by removing a delay chain in the BL precharging circuit. We'can obtain an yield of 100% at a program voltage of 5.5V on 94 manufactured sample dies when measured with memory tester equipment.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.24-32
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• 2015

National and international regulations on the exhaust gases of diesel engines are being strengthened, and a study of the combutsion engine and the post-porcessing system are in progress as a variety of ways. There are many techniques for the removal of nitrogen oxide like HC-SCR, LNT, Urea-SCR. And the technical development on the Urea-SCR owing to high conversion efficiency and fuel economy characteristics has being processed. This study investigated the physical/chemical properties of urea according to the change of the urea content, and were analysed the characteristic of exhaust gas. According to the increase of urea content, the contests of biuret aldehyde, phosphate content was increased and the changes of emission quantity of carbon monoxide, hydrocarbons and particulate matter in the exhaust gas was very slight. The emission quantity of NOx was decreased in accordance with increasing the urea content and it was shown to be more than 80 % in the urea solution having more than 30 wt%.

• Journal of the Korean Geotechnical Society
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• v.30 no.8
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• pp.25-37
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• 2014

In load and resistance factor design (LRFD) method, resistance factors are typically calibrated using resistance bias factors obtained from either only the data within ${\pm}2{\sigma}$ or the data except the tail values of an assumed probability distribution to increase the reliability of the database. However, the data selection approach has a shortcoming that any low-quality data inadvertently included in the database may not be removed. In this study, a data quality evaluation method, developed based on the quality of static load test results, the engineering characteristics of in-situ soil, and the dimension of aggregate piers, is proposed for use in constructing database. For the evaluation of the method, a total 65 static load test results collected from various literatures, including static load test reports, were analyzed. Depending on the quality of the database, the comparison between bias factors, coefficients of variation, and resistance factors showed that uncertainty in estimating bias factors can be reduced by using the proposed data quality evaluation method when constructing database.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.2
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• pp.268-276
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• 1998

Dentigerous cyst is a cyst arising by a seperation of follicles from around the anatomical crown of an unerupted tooth within the jaws. The dentigerous cyst is seen during routine radiographic examination. It is detected radiographically as a sharply delineated, round or oval, unilocular, homogeneous, and radiolucent area within which there is the crown of an unerupted tooth. The histological appearance of the dentigerous cyst is usually attached to the tooth at the cementoenamel junction and the sac lined by a thin, regular. stratified squamous epithelium. The dentigerous cyst can be treated by two surgical procedures: enucleation or marsupialization. The size and location of the lesion usually dictates the surgical procedures. The marsupialization consists of the removal of only a portion of the wall of the cyst to make the remaining cystic lining continous with the oral mucosa. The cyst, deprived of its supporting hydrostatic pressure, gradually shrinks until it is obliterated. The marsupialization is the best way to conserve the tooth affected by a dentigerous cyst and to permit its eruption. especially in a young person. Main advantages of the marsupialization are its relative simplicity and its conservation with respect to adjacent important structures. In marsupialization technique, a plugger can be constructed, if necessary, to maintain the opening and prevent food debris from entering the cystic cavity. However, the disadvantage is the potentiality of leaving pathologic tissues. Therefore frequent recall appointments are advisable.

• Journal of the Korea Society of Computer and Information
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• v.16 no.8
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• pp.85-93
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• 2011

In this paper, we analyzed the function elements of the Integrated meter reading system based on PLC which is working in Mok-dong, Seoul and studied how to improve the vulnerability. Also we propose an efficient method for the estimation of abnormal life status through frequency domain processing of utility meter readings. We found out that even after removing the high-frequency components from the raw meter data, the shape of the graph still maintains the original graph characteristics. The graph of the inverse transformed data has simpler and smoother curve than the original graph pattern. The original graph is not good to be used in deciding whether the residence's life pattern is normal or not. We could find out that the graph which is processed frequency signal has simple and intuitive graph pattern.

• Journal of the Korea Society of Computer and Information
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• v.10 no.1 s.33
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• pp.67-72
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• 2005

Most of image binarization algorithms analyzes the intensity distribution using the histogram for the determination of threshold value. When the intensity difference between the foreground object and the background is great, the histogram shows the tendency to be bimodal and the selection of the histogram valley as the threshold value shows the good result. On the other side. when the intensity difference is not great and the histogram doesn't show the bimodal property, the histogram analysis doesn't support the selection of the proper threshold value. This Paper Proposed the novel binarization method that applies the fuzzy membership function to each color value on the RGB color model and, by using the operation results, separates the features having the great readability from the background. The proposed method prevents the loss of information incurred by the gray scale conversion by using the RGB color model and extracts effectively the readable features by using the fuzzy inference Compared with the traditional binarization methods, the proposed method is able to remove the majority of noise areas and show the improved results on the image of transport containers , etc.