• Journal of Welding and Joining
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• v.21 no.6
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• pp.40-45
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• 2003

Steel members have advantages of resisting torsion and axial compression. In design, residual stresses at the welded joint of T-shape steel pipes are one of the most important points to be considered. In this paper, characteristics of residual stresses of welded joints are clarified by carrying out 3D non-steady heat conduction analysis and 3D thermal elastic-plastic FE-analysis. According to the results, the production mechanism of residual stresses at the welded joint of T-shape steel pipe is clarified. In this paper, circumferential stresses depended on thermal histories but axial and radial stresses were more dependent on geometrical shape than thermal histories. Residual stresses in the axial direction on the lower part of pipe member were tensile, controlled by geometrical shape. However, in case of middle part, residual stresses in all the directions were controlled by thermal histories.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1990.04a
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• pp.195-208
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• 1990

Flexible Manufacturing System(FMS) is an integrated, computer controlled complex of automated material handling devices and numerically controlled machine tools that can simultaneously process medium-sized volumes of a variety of part types. This paper discusses planning problems that can be solved for efficient use of an FMS and present an integrated decision support system for FMS production planning and scheduling problems. FMSDS(Flexible Manufacturing Systems Decision Support System) consists of data handling modules, part selection module, loading module, load adjusting module, scheduling module and simulation module etc. This paper presents the solution methodology of each subproblems and integrated interfaces between subproblems using hierarchical approaches and loop controls considering the relationships between subproblems. A case study by this model is presented.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.405-407
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• 2005

To evaluate the main hydrogeochemical characteristics, river waters are investigated using element리 and isotopic compositions in South Korea. In this area, the chemical compositions are mostly classified into three groups; $Ca^{2+}-{HCO_3}^-$ type, $Ca^{2+}-Cl^{-}-{NO_3}^-$ type and $Ca^{2+}-{HCO_3}^{-}-Cl^{-}-{NO_3}^-$ type. These types are affected by two major factors: water-rock interaction and anthropogenic inputs such as sewage and fertilizers. Based on the values of ${\delta}^{18}O$ and ${\delta}D$, most of waters are originated from precipitation except two samples contaminated. The lithology and geography of basins mainly control the water chemistry. Elemental and isotopic compositions show that water chemistry are mainly controlled by three end members, especially by carbonate dissolution, and suggest that anthropogenic input affect the water chemistry. Also, three weathering sources are identified: silicates, dolomite and limestone.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.05a
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• pp.21-26
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• 1999

In this study, to assess chip breaking characteristics of cold-drawn free machining steels, a newly developed non-dimensional parameter, chip breaking index, C/sub B/ has been adopted. And for comparison with free machining steels, chip breaking characteristics of conventional carbon steels were investigated. Properly controlled chips were produced with the C/sub B/ value of 0.05∼0.2, regardless of steel types. In case of cold-drawn free machining steels, however, cycle times of chip breaking are relatively shorter than those of conventional steels. And properly controlled chips were obtained from wider range of feed rate.

• The Korean Journal of Nuclear Medicine
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• v.18 no.2
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• pp.39-45
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• 1984

Investigating LVF directly, quantitatively and non-invasively by MUGA helps to validate and to follow up the effectiveness of new kinds of therapy. This is performed in controlled studies comparing groups of patients as demonstrated in the case of intracoronary thrombolysis. But it is also applicable on an individual basis. Contrary to the protocol in controlled studies medication was not discontinued in our patients before and after bypass surgery. This resembles the situation under routine conditions. Therefore the number of patients with reduced LVF was rather small before and after bypass operation. But, and this in the main result of our study, implementing MUGA for follow-up under this conditions can help: 1. To find out early those patients in whom LVF deteriorates postoperatively despite adequate medication. 2. To better define whether in cases of persistent or recurrent angina there is also deterioration of LVF. By this means MUGA can significantly contribute to find out whether reangiography is necessary or not, a question which often is difficult to answer in those patients.

• Journal of Periodontal and Implant Science
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• v.39 no.3
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• pp.311-320
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• 2009

Purpose: The aim of the present study was to analyze 7-year cumulative survival rate (CSR, %) of dental implants in the controlled diabetic patients and to evaluate the influence of the position, diameter and length of fixture, bone quality, age, gender and the method of maxillary sinus elevation on the survival rate. Methods: The data of 342 placed implants in the 104 diabetic patients collected between 1995 and 2007 at the Department of Periodontology in Yonsei University Hospital were analyzed. Results: Seven-year CSR of the 342 dental implants in the 104 controlled diabetic patients was 96.5%. The survival rates of the placed implants according the position have no statistically significant difference. The survival rates according to the length or diameter of the fixtures have no statistically significant difference. The survival rates according to the bone quality were 100% (Type I), 97.1% (Type II), 97.7% (Type III) and 85.7%(Type IV). The difference between the survival rate of Type I, II and III and that of Type IV was statistically significant. The survival rates according to patient gender were 96.8% (male), 95.5% (female). The survival rates according to patient age were 100% (${\leq}59$), 93.8% (${\geq}60$). The survival rates according to the method of sinus elevation in the maxillary posterior area were 96.8% (without sinus elevation), 92.9% (lateral approach) and 89.8% (crestal approach). Conclusions: Dental implants can be used successfully in the controlled diabetic patients. In case of upper posterior region which has poor bone density and older patients, the implant treatment should be more properly planed, executed, and followed-up.

• The Journal of Korean Medicine
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• v.31 no.1
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• pp.14-22
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• 2010

Objectives: This study aimed to evaluate any clinical research regarding asthma published by the Korean Oriental Medical Society and its sub-societies for future rigorous clinical research. Methods: Every article relevant to asthma was initially obtained from journals in the Korean Oriental Medical Society and its sub-societies by electronic search at journal web sites or manual search. Journals were limited to those registered by the Korea Research Foundation. From initial findings, two independent reviewers selected clinical articles and these articles were further analyzed separately into predefined criteria according to prospective and retrospective studies. For prospective studies, quality assessment was also conducted. Results: From 99 articles initially obtained, 19 were finally analyzed. 14 were prospective whereas 5 were retrospective. Among the prospective articles, there were no randomized controlled trials and the non-randomized studies had no control groups, with several problems of quality regarding pre-calculated study size and unbiased assessment. None of the retrospective studies described asthma diagnosis objectively and outcome measures were either non-relevant to asthma or non-validated. Conclusions: Well-designed randomized controlled studies for asthma are needed and more rigorous non-randomized controlled studies should be conducted.

• Herbal Formula Science
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• v.28 no.2
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• pp.199-209
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• 2020

Objectives : The purpose of this systematic review is to confirm whether Gwibitang is beneficial in chronic fatigue syndrome (CFS). Methods : Clinical trials were searched from databases including Pubmed, Embase, Central Cochrane, CNKI, Wanfang, CQVIP, CiNii, OASIS, Koreamed, and NDSL. The eligible study design was limited into randomized controlled trial, quasi-randomized controlled trial and controlled clinical trial. The outcomes included general effectiveness as nominal scale, and fatigue severity, insomnia severity and quality of life as interval or ratio scale. The meta-analysis and assessment of risk of bias was performed based on the data extracted from the selected trials. Results : The results of eight randomized controlled trials (n=596) were included in the meta-analysis. The results of the synthesis showed Gwibitang is beneficial substantially for relieving and managing the general symptoms, and its heterogeneity was not in important level (RR 0.26 [95% CI 0.17, 0.39], Z=6.47, P<0.00001, I²=0%). Gwibitang was beneficial for alleviating fatigue (SMD -0.78 [95% CI -1.27, -0.30], Z=3.17, P=0.002), but its certainty was low. In case of insomnia, too few trials had been found and their risk of bias was substantial, so no conclusions had been brought to. Conclusions : We found an evidence that Gwibitang could be beneficial for managing and alleviating main symptoms in CFS patients.

• The Journal of Pediatrics of Korean Medicine
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• v.26 no.4
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• pp.61-70
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• 2012

Objectives: Literature Study of clinical cases with Traditional Chinese Medicine (TCM) as reference for Korean medicine based treatment of juvenile patients with Down's syndrome. Methods: 4 TCM journals with the highest impact factors were searched and selected among the journals listed in www.cnki.net. The search keywords were "蒙古症", "唐氏症(産生唐氏症)", "唐氏症候群", "先天愚型", "伸舌樣痴呆", "21三体綜合徵", "三染色体症", "Down's syndrome", and "Mongolism". Accordingly, searched papers were analyzed. Results: Total 6 studies were selected: RCT(5), case report(1). Among the RCT related studies, 2 studies tested the effect of Electroacupuncture (電鍼), 1 study tested the effect of Electroacupuncture and Pharmacopuncture (藥鍼) treatment together, and 2 studies tested the effect of Electroacupuncture and Herbal Medicines (藥物) co-treatment. In all the studies, the study groups showed significantly improved intelligence quotient (IQ) in comparison with the control groups. The case report showed improvement of cognitive ability and other clinical parameters as a result of Acupuncture (鍼) and Herbal Medicines co-treatment in juvenile patients with Down's syndrome. Conclusions: Clinical studies testing the effect of TCM for the treatment of Down's syndrome have been conducted in small scales, and all the studies showed a certain level of brain function improvement of the patients in the study groups. These results implicate that the methods in Korean medicine can be highly potential treatment options for the treatment of Down's syndrome. Conduction of accurate and well-controlled studies in large scale would be required to prove the effect of Korean medicine for the treatment of patients with Down's syndrome.

• Journal of Oriental Neuropsychiatry
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• v.34 no.4
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• pp.403-420
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• 2023

Objectives: This study investigated the effectiveness of herbal medicine for generalized anxiety disorder (GAD) based on recent clinical studies. Methods: Studies were searched through four databases. Clinical research studies on herbal medicine treatment for GAD patients were included. The studies were analyzed according to study design, diagnostic criteria, population, and intervention. A risk of bias assessment was performed to assess the quality of the included randomized controlled trials (RCT). If the intervention applied to the treatment and control groups was the same and two or more studies were reporting the same items as outcome indicators, a meta-analysis was performed. Results: A total of 19 studies, including 12 RCTs were selected. The most common pattern identification was 'Phlegm fire disturbing upward' (痰熱上擾), and the most used herb for therapeutic purposes was 'Rhizome of Poria cocos' (茯苓). Meta-analysis results of three studies showed that there were no significant differences in effectiveness between the herbal medicine intervention and the Western medicine intervention. Meta-analysis results of five studies showed that the Hamilton Anxiety Rating Scale was significantly reduced in the case of herbal medicine intervention compared to Western medicine intervention. Conclusions: The results of our study demonstrated that herbal medicine treatment for GAD is effective in alleviating anxiety symptoms and chief symptoms of GAD. However, this study has several limitations; there was a lack of placebo-controlled RCT and an absence of objective diagnostic criteria in case reports. Therefore, further well-designed clinical studies, conducted based on the results of this study, are recommended.