• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.206-213
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• 2013

Transient response of a crack in a functionally graded piezoelectric material (FGPM) interface layer between two dissimilar homogeneous piezoelectric layers under anti-plane shear is analyzed using integral transform approaches. The properties of the FGPM layer vary continuously along the thickness. Laplace and Fourier transforms are used to reduce the problem to two sets of dual integral equations, which are then expressed to the Fredholm integral equations of the second kind. Numerical values on the dynamic energy release rate (DERR) are presented for the FGPM to show the effects on electric loading, gradient of the material properties, and thickness of the layers. Computed results yield following conclusions: (a) the DERR increases with the increase of the gradient of the material properties of the FGPM layer; (b) certain direction and magnitude of the electric impact loading impedes crack extension; (c) increase of the thickness of the FGPM layer and the homogeneous piezoelectric layer which has larger material properties than those of the crack plane are beneficial to increase of the resistance of transient fracture of the FGPM layer.

• Nutrition Research and Practice
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• v.13 no.6
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• pp.488-497
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• 2019

BACKGROUND/OBJECTIVES: There are various factors that affect metabolic abnormalities related to obesity. The purpose of this study is to analyze the differences in dietary intakes and body compositions of obese women according to metabolic risks and to classify them as metabolically healthy obese (MHO) or metabolically abnormal obese (MAO). SUBJECTS/METHODS: This study was conducted on 59 obese Korean women aged 19 to 60 years. NCEP-ATPIII criteria were applied and the women classified as MHO (n = 45) or MAO (n = 14). Body composition of each subject was measured by using dual-energy x-ray absorptiometry (DEXA). Three-day food records were used to analyze dietary intake. Eating habits and health-related behaviors were determined through questionnaires. Indirect calorimetry was used to measure resting metabolic rate and respiratory rate. RESULTS: The average age of the subjects was 43.7 years. The analysis of body composition according to phenotype revealed significantly higher body fat mass (P < 0.05), arm fat mass (P < 0.05), and android fat mass (P < 0.05), as measured by DEXA, in the MAO group than in the MHO group. There was no significant difference in the dietary intake of the two groups. However, eating behaviors differed. Compared to the MHO group, the MAO women had a shorter meal time (less than 10 minutes), a preference of oily foods, and a tendency to eat until full. Therefore, the eating habits of MHO women were more positive than those of MAO women. CONCLUSIONS: The results suggest that fat distribution in each body region affects various metabolic abnormalities. A high level of arm fat mass in obese Korean women may increase metabolic risk. In addition, eating habits of obese Korean women are considered to be environmental factors affecting the metabolic phenotype of obese Korean women.

• Journal of the Korea Society of Computer and Information
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• v.24 no.3
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• pp.201-208
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• 2019

The government has proposed a development model for universities to strengthen the capacity of the College of Humanities as part of the university restructuring policy in line with the trend of the times, and encouraged each university to voluntarily induce the establishment of the humanities development plan through financial support under their own individual conditions. With the decline in the school-age population due to the declining fertility rate, the rapid change in the industrial structure has highlighted the decline in the employment rate of the students of the humanities. Therefore, the government is implementing university grading based on the results of the university structural reform evaluation, and pressing low-grade universities through reduction of capacity and reduction of support. In the course of this change, universities have designated the College of Humanities as the primary target of integration with other majors or and its disintegration. This study examines the direction of the government's attempt to change the humanities in the era of the Fourth Industrial Revolution, and suggests a precedent example during the reform of the humanities college. If the humanities college is integrated with practical studies such as management, design, IT, CT, and engineering, the strengths of the humanities can be highlighted. However, the results of this study suggest that many variables such as consideration of students' aptitudes and interests in the integration process of majors, autonomy in major selection, understanding between departments integrated, and demand for a single major before integration or disintegration should be considered. In addition, an example of a local private university shows that the hasty attempt to integrate or disintegrate the humanities can rather lead to various educational harms.

• Journal of Gastric Cancer
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• v.19 no.2
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• pp.157-164
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• 2019

Purpose: Although standard radical gastrectomy is recommended after noncurative resection of endoscopic submucosal dissection (ESD) for early gastric cancer in most cases, residual tumor and lymph node metastasis have not been identified after surgery. The aim of this study is to evaluate the feasibility of sentinel node navigation surgery after noncurative ESD. Materials and Methods: This trial is an investigator-initiated, multicenter prospective phase II trial. Patients who underwent ESD for clinical stage T1N0M0 gastric cancer with noncurative resections were eligible. Qualified investigators who completed the prior phase III trial (SENORITA 1) are exclusively allowed to participate. In this study, 2 detection methods will be used: 1) intraoperative endoscopic submucosal injection of dual tracer, including radioisotope and indocyanine green (ICG) with sentinel basins detected using gamma-probe; 2) endoscopic injection of ICG, with sentinel basins detected using a fluorescence imaging system. Standard laparoscopic gastrectomy with lymphadenectomy will be performed. Sample size is calculated based on the inferior confidence interval of the detection rate of 95%, and the calculated accrual is 237 patients. The primary endpoint is detection rate, and the secondary endpoints are sensitivity and postoperative complications. Conclusions: This study is expected to clarify the feasibility of laparoscopic sentinel basin dissection after noncurative ESD. If the feasibility is demonstrated, a multicenter phase III trial will be initiated to compare laparoscopic sentinel node navigation surgery versus laparoscopic standard gastrectomy in early gastric cancer after endoscopic resection.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4B
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• pp.421-428
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• 2008

For last decades, the rapid coastal erosion process spreading along Korean peninsular has become a nuisance especially for tourism and local economy. Global warming and sea-level rise demand persistently new coastal protection strategies against the conventional methods using armored structures. In a view of this, Kweon et al. (2007) has proposed a new type of horizontal steel plates for an ideal candidate as eco-friendly detached breakwater systems for global warming era. The breakwater is composed of piles and horizontal porous plates that was devised for the optimized blockage effects and wave energy dissipations. This system provides outstanding performances as wave barrier and added advantages such as a rapid installation, an easy relocation, a perfect water circulation for the stagnation of pollutions in sheltered regions. The present experimental study focuses on the performance evaluations of the proposed system in wind wave conditions as a wave dissipator and reflector. The reflection, transmission, and energy dissipation of the random waves has been discussed in detail based on a newly proposed relation between wave steepness and a plate width normalized by wave length that are major factors affecting the wave transmission.

• Hip & pelvis
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• v.35 no.3
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• pp.175-182
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• 2023

Purpose: This study aims to compare patients in whom fixation failure occurred via cut-out (CO) or cut-through (CT) in order to determine patient factors and radiographic parameters that may be predictive of each mechanism. Materials and Methods: This retrospective cohort study includes 18 patients with intertrochanteric (IT) hip fractures (AO/OTA classification 31A1.3) who underwent treatment using a single lag screw design intramedullary nail in whom fixation failure occurred within one year. All patients were reviewed for demographics and radiographic parameters including tip-to-apex distance (TAD), posteromedial calcar continuity, neck-shaft angle, lateral wall thickness, and others. Patients were grouped into cohorts based on the mechanism of failure, either lag screw CO or CT, and a comparison was performed. Results: No differences in demographics, injury details, fracture classifications, or radiographic parameters were observed between CO/CT cohorts. Of note, a similar rate of post-reduction TAD>25 mm (P=0.936) was observed between groups. A higher rate of DEXA (dual energy X-ray absorptiometry) confirmed osteoporosis (25.0% vs. 60.0%) was observed in the CT group, but without significance. Conclusion: The mechanism of CT failure during intramedullary nail fixation of an IT fracture did not show an association with clinical data including patient demographics, reduction accuracy, or radiographic parameters. As reported in previous biomechanical studies, the main predictive factor for patients in whom early failure might occur via the CT effect mechanism may be related to bone quality; however, conduct of larger studies will be required in order to determine whether there is a difference in bone quality.

• Clean Technology
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• v.12 no.2
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• pp.67-77
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• 2006

A simple dual sludge process, called as $KNR^{(R)}$ (Kwon's Nutrient Removal) system, was developed for small sewage treatment. It is a hybrid system that consists of an UMBR (Upflow multi-layer bioreactor) as anaerobic and anoxic reactor with suspended denitrifier and a post aerobic biofilm reactor, filled with pellet-like media, with attached nitrifier. To evaluate the stability and performance of this system for small sewage treatment, the pilot-scale $KNR^{(R)}$ plant with a treatment capacity of $50m^3/d$ was practically applied to the actual sewage treatment plant, which was under retrofit construction during pilot plant operation, with a capacity of $50m^3/d$ in a small rural community. The HRTs of a UMBR and a post aerobic biofilm reactor were about 4.7 h and 7.2 h, respectively. The temperature in the reactor varied from $18.1^{\circ}C$ to $28.1^{\circ}C$. The pilot plant showed stable performance even though the pilot plant had been the severe fluctuation of influent flow rate and BOD/N ratio. During a whole period of this study, average concentrations of $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, and TP in the final effluent obtained from this system were 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, and 0.87/0.17 mg/L (with/without poly aluminium chloride(PAC)), which corresponded to a removal efficiency of 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, and 55.4/90.3%, respectively. Excess sludge production rates were $0.026kg-DS/m^3$-sewage and 0.220 kg-DS/kg-BOD lower 1.9 to 3.8 times than those in activated sludge based system such as $A_2O$ and Bardenpho.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.23-29
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• 2000

Purpose: It has recently been recognized that Helicobacter pylori (H. pylori) is an important factor in the pathogenesis of recurrent abdominal pain (RAP) in children. But, the best treatment for H. pylori infection is still unsettled. This study was performed to evaluate the efficacy of 2 weeks dual therapy with proton pump inhibitor (PPI) and amoxicillin for children with H. pylori infection associated with RAP. Method: Our study included 24 children with RAP who were H. pylori positive assessed by CLO test and histologic examination (silver stain). We used the regimen consisted of PPI (omeprazole, 0.7 mg/kg/day) and amoxicillin (50 mg/kg/day) for 2 weeks to eradicate H. pylori. Eradication of H. pylori was determined 4 weeks after the termination of treatment using the CLO test and histologic examination. Results: The endoscopic diagnoses of patients were nodular gastritis in 11 cases, superficial gastritis in 7 cases, peptic ulcer in 4 cases and normal finding in 2 cases. H. pylori was eradicated in 12 cases by omeprazole and amoxicillin dual therapy for 2 weeks and the eradication rate was 50%. In 4 of 12 children in whom H. pylori had not been eradicated with that regimen, we successfully eradicated H. pylori with other regimens of which 2 or 3 drugs among omeprazole, amoxicillin, clarithromycin, colloidal bismuth subcitrate ($Denol^{(R)}$) and metronidazole were used. Conclusion: The dual therapy with PPI and amoxicillin for 2 weeks had no clear advantage over other regimens for the eradication of H. pylori infection in children. We concluded that the combi-nation of PPI and amoxicillin for 2 weeks is not so good for H. pylori eradication as other commonly used regimens.

• Korea journal of population studies
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• v.21 no.2
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• pp.37-57
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• 1998

In recent, Korea introduced the local self-government system. And the local government tried to establish and implement plans for women. Those plans were established on the basis of not the particular environments of regional societies but similar policies of central government. Despite of geographical migrations, we can find differences of population structure and economic status among regions. As the result, most of regional policies for women were ineffective. This paper examines population structure and economic status of women by regions and recommends the long and medium direction for local policies for women. For analysis, it utilizes the 2% sample data-set of National Statistical Office's '1995 Population and Housing Census' in Korea. The findings of this paper are summarized as following; Firstly, the dependency rate of Chungchong-do, Cholla-do, Kyongsangnam-do will reach about 45% in 2000. Therefore, as soon as possible, those local government should establish the labor policies to enhance the economically active participation rate of the elderly persons and welfare policy for them. Secondly, the level of women's economic participation. Thus, local governments should set up labor market policies for women according to regional situations. For examples, in Kyonggi-do, Seoul, Daejeon, Daeku which unemployment rate of the highly educated women are relatively high, those local governments should seek the measures to tackle unemployment problem of them. Thirdly, due to the differences regional economic structure, women's employment structures differed also by region. Hence, local governments should formulate suitable plans to consider the working status of regional women's workers.

• Journal of Pharmacopuncture
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• v.25 no.2
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• pp.106-113
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• 2022

Objectives: Herbal medicine is a worldwide health topic. Vitex agnus-castus L. (VAC) is a popular plant used for gynecologic problems due to its hormonal effects. The aim of this study is to reveal VAC extract effect on fetus when this herb is used started from antenatal period or during pregnancy. Methods: Performed from starting day of January 2019 till February 2019, 48 rats were assigned in randomly divided eight-member six groups: control (C1), treated group with 365 mg/kg VAC from initiation of insemination (T1) and 30 days prior to pregnancy (T2), control that underwent caesarean section on 15^th day of gestational age (C2) and treated group with 365 mg/kg VAC from initiation of insemination (T3) and 30 days prior to pregnancy (T4) that underwent caesarean section. Weight, sex and number of fetuses, abortion and still birth rate and estradiol level were evaluated using t-test by SPSS software. Results: We showed increased weight among T1 group considering totally and sex-dependent which is significant (all p-value < 0.05). We also detected significantly decreased weight in T2 in total (p-value < 0.0001) and when considering female fetuses (0.043) but not males (0.17). Although the results showed slightly non-significant increased weight among fetuses of T3 (totally or based on the fetus sex) compared to the control group (C2), T4 group had statistically decreased weight compared to control group. Pregnancy rate and pregnancy outcome were affected by VAC usage. The time of VAC initiation also affected live birth and abortion rates. Conclusion: VAC extract may affect pregnancy rate, live birth rate, abortion and stillbirth rates. Its effect on the weight and the sex showed dual pattern depends on the time of initiation and pregnancy trimester of evaluation. Prescribing this medicinal plant for patients being prone to pregnancy should be with caution. Further study is recommended.