• Composites Research
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• v.24 no.1
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• pp.1-9
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• 2011

This paper presents an experimental and numerical study on composite tubes for the energy absorber of the high-speed train. The purpose of the experimental study is to find out which lay-up is the best lay-up for the energy absorber. Four lay-ups were tested using quasi static method: $[0/45/90/-45]_4$, $[0]_{16}$, $[0/90]_8$, $[0/30/-30]_5$. Two triggering methods were used to create initial damage and guarantee the progressive collapse mode: bevel edge and notch edge. As a result, $[0/45/90/-45]_4$ lay-up was find out the best lay-up among the laminates being tested. In the numerical study, a parametric analysis was done to find out the most proper way to simulate the quasi static test of a composite tube using LS-DYNA program. A single composite tube was modeled to be crashed by a moving wall. Comparison between simulation and experiment was done. Reasonable agreement between experiment and analysis was obtained. Dealing with parameter TFAIL and the mass scaling factor, this parametric study shows the ability and the limitation of LS-DYNA in modeling the quasi static test for the composite tube.

• Journal of Periodontal and Implant Science
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• v.44 no.2
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• pp.71-78
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• 2014

Purpose: Host modulatory therapy has been proposed as a treatment for periodontal diseases. A class of herbal medicines, known to be immunomodulators, alters the activity of immune function through the regulation of informational molecules such as cytokines. In the current study, we tested the hypothesis that herbal immunomodulator drugs act as an adjuvant to scaling and root planing (SRP) in alleviating periodontal inflammation by improving clinical and biochemical parameters. Methods: Sixty healthy subjects (30 in each group) with moderate and severe chronic periodontitis were enrolled in a double-blind, placebo-controlled, double-masked randomised controlled trial. The control group was treated with SRP and a placebo, whereas the test group was treated with SRP followed by dietary supplementation of Septilin for 3 weeks. Periodontal clinical parameters and serum C-reactive protein (CRP) levels were evaluated for all patients at the baseline, 3 weeks, and 6 weeks. Results: Improved gingival index scores found in the test group as compared to the control group were found to be statistically significant only after 3 weeks (P<0.001). In contrast, the decrease in the sulcus bleeding index and pocket depth scores was statistically highly significant in the test group as compared to the control group after 3 weeks and 6 weeks (P<0.001). However, reduced clinical attachment level and CRP scores, as reflected in the test group as compared to the control group, were not found to be statistically significant after both 3 weeks (P>0.05) and 6 weeks (P>0.05). Conclusions: The results of this clinical-biochemical study suggest that dietary supplementation with herbal immunomodulatory agents may be a promising adjunct to SRP and may aid in improving periodontal treatment outcomes.

• Journal of Periodontal and Implant Science
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• v.51 no.4
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• pp.276-284
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• 2021

Purpose: The aim of this randomized clinical trial was to assess whether chemical cleansing using a sulfonic/sulfuric acid gel solution (HBX) as an adjunct to scaling and root planing (SRP) resulted in a decrease in residual plaque and calculus in deep periodontal pockets compared to SRP alone. Methods: Fifty-six patients with 56 hopeless posterior teeth, scheduled for extraction due to severe periodontitis, were enrolled in this study. Each tooth was randomly assigned to 1 of the 2 experimental procedures. The test teeth were subjected to the irrigation of the subgingival area with HBX for 2 minutes, followed by SRP with hand and ultrasonic instruments for 14 minutes, and then extracted. The control teeth received only mechanical instrumentation before extraction. Residual biofilm was evaluated on photographs and measured as total area and percentage of root surface covered by remaining plaque (RP) or calculus (RC) after treatment. Results: The initial pocket depth (PD) and total subgingival root surface area were similar between the 2 treatment groups. After treatment, the total subgingival root area covered by RP and RC was statistically significantly larger (P<0.001) in the control group than in the test group. The test teeth showed a lower percentage of RP, but a higher percentage of RC than the control teeth (both P<0.001). Complete calculus removal was achieved in 42% of the control teeth surfaces and in 25% of the test teeth surfaces for a PD of 4 mm. Conclusions: The additional chemical cleansing with HBX resulted in a statistically significant improvement in bacterial plaque removal during SRP of deep pockets, but it was not effective in reducing calculus deposits.

• Journal of Periodontal and Implant Science
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• v.44 no.4
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• pp.169-177
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• 2014

Purpose: We aimed to investigate the impact of nonsurgical periodontal treatment combined with one-year dietary supplementation with omega (${\omega}$)-3 on the serum levels of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), and arachidonic acid (AA). Methods: Fifteen patients with chronic generalized periodontitis were treated with scaling and root planing. The test group consisted of seven patients ($43.1{\pm}6.0$ years) supplemented with ${\omega}$-3, consisting of EPA plus DHA, three capsules, each of 300 mg of ${\omega}$-3 (180-mg EPA/120-mg DHA), for 12 months. The control group was composed of eight patients ($46.1{\pm}11.6$ years) that took a placebo capsule for 12 months. The periodontal examination and the serum levels of DPA, EPA, DHA, and AA were performed at baseline (T0), and 4 (T1), and 12 (T2) months after therapy. Results: In the test group, AA and DPA levels had been reduced significantly at T1 (P<0.05). AA and EPA levels had been increased significantly at T2 (P<0.05). The ${\Delta}EPA$ was significantly higher in the test compared to the placebo group at T2-T0 (P=0.02). The AA/EPA had decreased significantly at T1 and T2 relative to baseline (P<0.05). Conclusions: Nonsurgical periodontal treatment combined with ${\omega}$-3 supplementation significantly increased the EPA levels and decreased the AA/EPA ratio in serum after one year follow-up. However, no effect on the clinical outcome of periodontal therapy was observed.

• Journal of Korean society of Dental Hygiene
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• v.10 no.4
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• pp.607-616
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• 2010

Objectives : This study was performed to enhance a rate of Using oral clinic and to search related factors of using oral clinics. Methods : The subjects of the study were 74,698 subjects who answered to the 2007 korea Youth Risk Behavior Web-based survey. Answers of 73,836 subjects were used for the final analysis. We used spss of version 12.0. This study conducted a Chi-square test to identify using oral clinics rate according to characteristics of subjects and a multivariate logistic regression analysis to identify whether they are independently significant. Results : Tooth scaling experiences were responded by 10,060 subjects(25.6%). Grade and metropolis, economic level had significant associations with using oral clinic experiences. The rate of using oral clinic showed significant difference in point, depending on general characteristics. Their oral health showed significant difference in point between using oral clinic experience and non-experience groups. According to the multiple logistics regression analysis whose significant independent variables were sex, grade, metropolis, economic level, blooding gum, tooth brushing, oral malodor. Conclusions : The policy is needed to prevent economic constraints from worsening oral health by supporting the poor. And our government should eventually prepare a public relation program suitable for public.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1568-1572
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• 2004

This paper proposes a new online calibration algorithm for the array antenna system. As you know, the several previous calibration methods for the mutual coupling did not estimate but measure mutual coupling effect at the real or test-bed system directly. Therefore we suggest some idea to compensate the calibration errors due to mutual coupling effect and mismatch in cables and electronic modules without the off-line calibration. In this work, we can calibrate the array antenna system under the operation of the system using Independent Component Analysis(ICA). This is what is called an online calibration. As you know, the ICA method has permutation and scaling problems. However, we solve problems of the ICA method and apply it to the calibration of an array antenna. The method simultaneously estimates the DOA(Direction of Arrival) of the signals, and calibrates the array for that specific angle. The proposed algorithm is evaluated by computer simulation and its behavior is illustrated by a numerical example.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.212-221
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• 2007

Objectives : This study was conducted to test patients with Atopic Dermatitis by external application with Gynostemma Pentaphyllum MAKINO in cosmetics. Methods : We gave scores to 59 patients who visited the Dept. of Oriental Medical Opthalmology & Otolaryngology & Dermatology of Daegu Hanny Oriental Medical Center from July 1st, 2005 to December 31th. We checked the clinic index score(extent. intensity : the degree of erythema, induration or papulation, puritus, excorination, lichenification, scaling or dryness, erosion or oozing or weeping. the degree of itching), Eosinophil count and IgE. Results : There are 46 patients we could check by clinic index score, and 44 patients by laboratory. 1. In the 46 cases clinic index score was significantly decreased between the before- and afterexternal application treatment periods(P<0.01). 2. The 46 cases was devided into two types (moist heat type and blood dryness type) by intensity. External application of Gynostemma Pentaphyllum MAKINO in cosmetics did not significant change by two types. 3. In the 44 laboratory cases, the number of eosinophil counts was decreased but the number of IgE was significantly increased. Conclusions : Considering the above results, we have concluded that cosmetics with Gynostemma Pentaphyllum MAKINO have the remedical effect for Atopic Dermatitis.

• Journal of Korean Academy of Nursing
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• v.37 no.3
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• pp.324-333
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• 2007

Purpose: The purpose of this study was to develop and evaluate a quality of life scale for Korean patients with cancer (C-QOL). Methods: The C-QOL was developed and validated as follows, item generation, pilot study, and psychometric tests. A total of 337 patients diagnosed with stomach, liver, lung, colon, breast, or cervix cancer were recruited. The patients were asked to complete the preliminary questionnaire comprising the content-validated items, the SF-36, and the ECOG performance status. The obtained data was analyzed using descriptive statistics, factor analysis, multidimensional scaling (MDS), multitrait/multi-item matrix, ANOVA, t-test, and Cronbach's alpha. Results: Preliminarily twenty-six items were generated through content validity and a pilot study. Factor analysis and MDS extracted a total of 21 items with a 5-point Likert-type scale (C-QOL). The C-QOL included five subscales: physical status (6 items), emotional status (6 items), social function (3 items), concern status (2 items), and coping function (4 items). The C-QOL established content validity, construct validity, item convergent and discriminant validity, known-groups validity, reliability, and sensitivity. Conclusion: The Newly developed C-QOL is an easily applicable instrument which established psychometric properties and reflected Korean culture. It is recommended for further study to examine the responsiveness of the C-QOL using a longitudinal research design.

• Smart Media Journal
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• v.9 no.3
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• pp.80-89
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• 2020

Out - of - distribution (OOD) samples are frequently encountered when deploying a classification model in plenty of real-world machine learning-based applications. Those samples are normally sampling far away from the training distribution, but many classifiers still assign them high reliability to belong to one of the training categories. In this study, we address the problem of removing OOD examples by estimating marginal density estimation using variational autoencoder (VAE). We also investigate other proper methods, such as temperature scaling, Gaussian discrimination analysis, and label smoothing. We use Chonnam National University (CNU) weeds dataset as the in - distribution dataset and CIFAR-10, CalTeach as the OOD datasets. Quantitative results show that the proposed framework can reject the OOD test samples with a suitable threshold.

• International Journal of Fluid Machinery and Systems
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• v.2 no.4
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• pp.346-352
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• 2009

The objective of the present work is to improve numerical predictions of unsteady turbulent swirling flows in the draft tubes of hydraulic power plants. We present Large Eddy Simulation (LES) results on a simplified draft tube consisting of a straight conical diffuser. The basis of LES is to solve the large scales of motion, which contain most of the energy, while the small scales are modeled. LES strategy is here preferred to the average equations strategies (RANS models) because it resolves directly the most energetic part of the turbulent flow. LES is now recognized as a powerful tool to simulate real applications in several engineering fields which are more and more frequently found. However, the cost of large-eddy simulations of wall bounded flows is still expensive. Bypass methods are investigated to perform high-Reynolds-number LES at a reasonable cost. In this study, computations at a Reynolds number about 2 $10^5$ are presented. This study presents the result of a new near-wall model for turbulent boundary layer taking into account the streamwise pressure gradient (adverse or favorable). Validations are made based on simple channel flow, without any pressure gradient and on the data base ERCOFTAC. The experiments carried out by Clausen et al. [1] reproduce the essential features of the complex flow and are used to develop and test closure models for such flows.