• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1500-1502
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• 1997

We investigated the tracking and erosion resistance of the silicone rubber by Inclined-Plane Method. And, with the variation of the accelerated conditions such as the applied voltage and composition of contaminant, the change of the tracking characteristics according to such conditions was evaluated. The leakage current significantly increases with the increasing voltage, but the weight loss remains almost the same. The voltage above 5.0 kV isn't recommended because tracking breakdown occurs as fast as it does without erosion, and the typical discharge waveform was the form of rectifying wave.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2166-2168
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• 2005

This paper presents the frequency - dependent characteristics of leakage currents flowing through ZnO varistor. The leakage current - voltage (V-I) characteristic curves of the commercial ZnO varistor were measured. The resistive leakage current was increased with increasing the magnitude and frequency of the applied voltage in the low conduction region. The power losses of ZnO varistor increase as the frequency of applied voltage increases, because of the dielectric loss related to the frequency of the test voltage.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.455-461
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• 2021

Cardiomegaly is one of the most common diseases seen on chest X-rays, but if it is not detected early, it can cause serious complications. In view of this, in recent years, many researches on image analysis in which deep learning algorithms using artificial intelligence are applied to medical care have been conducted with the development of various science and technology fields. In this paper, we would like to evaluate whether the Inception V3 deep learning model is a useful model for the classification of Cardiomegaly using chest X-ray images. For the images used, a total of 1026 chest X-ray images of patients diagnosed with normal heart and those diagnosed with Cardiomegaly in Kyungpook National University Hospital were used. As a result of the experiment, the classification accuracy and loss of the Inception V3 deep learning model according to the presence or absence of Cardiomegaly were 96.0% and 0.22%, respectively. From the research results, it was found that the Inception V3 deep learning model is an excellent deep learning model for feature extraction and classification of chest image data. The Inception V3 deep learning model is considered to be a useful deep learning model for classification of chest diseases, and if such excellent research results are obtained by conducting research using a little more variety of medical image data, I think it will be great help for doctor's diagnosis in future.

• Journal of Forest and Environmental Science
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• v.28 no.1
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• pp.24-29
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• 2012

This paper assesses the stmpage value of Korean white pine (Pinus koraiensis) stands in the Research Forest of Kangwon National University. Assessment was done by means of the cost value method (Faustmann formula) for age class I, Glaser method for age class II-V, and inversion market method for age class over VI. Generally the value of stumpage is calculated by the inversion market method in the market. However, immature trees and middle age class trees are not assessed in market, and the Korean forest is not old enough to harvest. So, when forests are damaged by attacks from forest fire, blight and harmful insects, the forest cannot be compensated for the loss from the government or insurance company. For this reason, the value of all-age class trees are calculated by using appropriate methods. As a result, the value of age I class stands (0.3 ha) is calculated as 1,786,305 (won), age II-Vclass stands (22.1 ha) 206,677,975 (won) and age VI class and over stands (24.8 ha) 523,789,603 (won).

• BMB Reports
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• v.43 no.10
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• pp.693-697
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• 2010

Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant syndrome characterized by predisposition to early-onset cancers. HNPCC is caused by heterozygous loss-of-function mutations within the mismatch repair genes MLH1, MSH2, MSH6, PMS1, and PMS2. We genotyped the MLH1 and MSH2 genes in patients suffering from Lynch syndrome and in 11 unrelated patients who were diagnosed with colorectal cancer and had subsequently undergone surgery. Five Lynch syndrome patients carried germline mutations in MLH1 or MSH2. Two of these were identified as known mutations in MLH1: deletion of exon 10 and a point mutation (V384D). The remaining three patients exhibited novel mutations: a duplication (937_942dupGAAGTT) in MLH1; deletion of exons 8, 9, and 10; and a point mutation in MLH1 (F396I) combined with multiple missense mutations in MSH2 (D295G, K808E, Q855P, and I884T). The findings underline the importance of efficient pre-screening of conspicuous cases.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.4
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• pp.436-447
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• 2013

In this paper, Integrated circuit(IC) electromagnetic(EM) conducted immunity measurement and simulation using bulk current injection(BCI) and direct power injection(DPI) methods were conducted for 1.8 V I/O buffers. Using the equivalent circuit models developed for IC electromagnetic conducted immunity tests, we investigated the reliability of the frequency region where IC electromagnetic conducted immunity test is performed. The insertion loss for the noise injection path obtained from the simulation indicates that using only one conducted immunity test method cannot provide reliable conducted immunity test for broadband noise. Based on the forward power results, we analyzed the actual amount of EM noise injected to IC. We propose a more reliable immunity test methods for broad band noise.

• Journal of the Korean Electrochemical Society
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• v.9 no.4
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• pp.170-177
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• 2006

Optimum design of flow channel in the separation plate of Proton Exchange Membrane Fuel Cell is very prerequisite to reduce concentration over potential at high current region and remove the water generated in cathode effectively. In this paper, fully 3 dimensional computational model which solves anode and cathode flow fields simultaneously is developed in order to compare the performance of fuel cell with parallel and interdigitated flow channels. Oxygen and water concentration and pressure drop are calculated and i-V performance characteristics are compared between flows with two flow channels. Results show that performance of fuel cell with interdigitated flow channel is hi민or than that with parallel flow channel at high current region because hydrogen and oxygen in interdigitated flow channel are transported to catalyst layer effectively due to strong convective transport through gas diffusion layer but pressure drop is larger than that in parallel flow channel. Therefore Trade-off between power gain and pressure loss should be considered in design of fuel cell with interdigitated flow channel.

• Journal of Periodontal and Implant Science
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• v.51 no.2
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• pp.100-113
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• 2021

Purpose: Previous studies have solely focused on fresh extraction sockets, whereas in clinical settings, alveolar sockets are commonly associated with chronic inflammation. Because the extent of tissue destruction varies depending on the origin and the severity of inflammation, infected alveolar sockets may display various configurations of their remaining soft and hard tissues following tooth extraction. The aim of this study was to classify infected alveolar sockets and to provide the appropriate treatment approaches. Methods: A proposed classification of extraction sockets with chronic inflammation was developed based upon the morphology of the bone defect and soft tissue at the time of tooth extraction. The prevalence of each type of the suggested classification was determined retrospectively in a cohort of patients who underwent, between 2011 and 2015, immediate bone grafting procedures (ridge preservation/augmentation) after tooth extractions at Seoul National University Dental Hospital. Results: The extraction sockets were classified into 5 types: type I, type II, type III, type IV (A & B), and type V. In this system, the severity of bone and soft tissue breakdown increases from type I to type V, while the reconstruction potential and treatment predictability decrease according to the same sequence of socket types. The retrospective screening of the included extraction sites revealed that most of the sockets assigned to ridge preservation displayed features of type IV (86.87%). Conclusions: The present article classified different types of commonly observed infected sockets based on diverse levels of ridge destruction. Type IV sockets, featuring an advanced breakdown of alveolar bone, appear to be more frequent than the other socket types.

• Journal of Korean Academy of Nursing
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• v.26 no.4
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• pp.917-929
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• 1996

The purpose of this study is to explore types of postpartum depression and to understand the nature and structure of the postpartum depression by using Q-methodological approach. As a way of research, 55 statements concerning postpartum depression were selected through individual interviews with postpartum mothers and literature review. 30 women were chosen as a subject group for the study, with opinions shown in 55 statements divided into 9 scales by forced distribution. PC QUANL Program was used for analysis and Q-factors were analyzed by using principal component analysis. As a result, postpartum depression experience was classified into 5 types. There are "Role-Strain Type", "Unattributional Depression Type", "Psychosomatic Symptoms Type", "Self-Compassion Type", and "Role-Crisis Type". Type I was named "Role-Strain Type", referring to the strain generally experienced by mothers with regard to the new role as a mother and as a social member. Type II was named "Unattributional Depression Type", referring to the symptom experienced by people who were in a state of vanity and a sense of loss. They often break into tears for no specific reasons. In case of Type III, people in a state of "Psychosomatic Symptoms Type" develop physical symptoms after suffering from inherent emotional conflict. Type IV was named "Self-Compassion Type" refers to the symptom shown by those who feel pity for their children and for themselves. And they show inability to cope with the reality properly. Type V was named "Role -Crisis Type", which is experienced by people who have a burden and a severe fear of their own job and their children in their mind, also showing serious conflict with maternal role. Futhermore, it was carried out to examine structure of postpartum depression in terms of degree of depression and adjustment ability. Type I showed mild degree of depression and relatively good adjustment ability. Type II showed broad range of degree in depression and moderate adjustment ability. Type III showed moderate depression and relatively low adjustment ability. Type IV revealed relatively serious degree of depression and the lowest adjustment ability. Type V revealed very serious degree of depression and the lowest adjustment ability. As a result, considering the structure of postpartum depression. Type I is considered to be a normal depression sympton which most mothers generally experience, followed by Type II, Type III, Type IV and Type V, each of which show increasingly worse degree of depression and lower adjustment ability. In conclusion, it seems to be it is necessary to understand distinct symptoms of postpartum depression and to examine the characteristics and structure of those types, so that it could lead to more individual nursing approach.cteristics and structure of those types, so that it could lead to more individual nursing approach.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.415-418
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• 1999

The characteristics of VRLA (valve regulated Iead-acid) battery with the tubular positive plate and gel type electrolyte were examined as a function of active material filling density. The filling density of positive plate was 3.2 g/mL, 3.4 g/mL, and 3.6 g/mL, respectively. These VRLA batteries were cycled with 100% DOD (depth of discharge) at the $C_5/5$ rate, followed by IU-type recharge with $I_{max}=0.2C_{10}/10$ and a final voltage V=2.40 V/cell. The test was performed in a thermostatic room at $25{\pm}1^{\circ}C$. The result indicated that the initial capacity was independent of active material filling density, i.e., the highest initial capacity was 3.4 g/mL of filling density and the lowest was 3.6 g/mL. On aspect of the cycle-life performance of the VRLA battery, the filling density of 3.6 g/mL was similar to that of 3.4 g/mL in the positive plate, and both were higher than that of 3.2 g/mL. Water-loss and degradation of the VRLA battery were decreased according to an increase of the filling density in the positive plate. The optimum filling density of the active material was 3.4~3.6 g/mL.