• Journal of the Korean Ceramic Society
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• v.33 no.9
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• pp.977-984
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• 1996

This paper analyzes the performance of a rectangular dielectric ceramic antenna by the theoretical cavity model such as input impedance resonant frequency quality factor efficiency and bandwidth. Through a compu-ter simulation variation of the antenna characteristics is found as a function of the antenna parametes. (permit-tivity permeability antenna size etc) Based on the results we propose a new design method for the dielectric ceramic antenna to be employed in Global Positioning Systems.

• Proceedings of the KSR Conference
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• 2002.10a
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• pp.247-252
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• 2002

It is expected to confront numerous technological advancements in ter railroad technology with an opening of state-of-art Kyung-Bu High Speed Railroad that permits traveling speed in excess of 300 Km/hr. Expansions of railroad facility such as revival of silk railroad in Eurasia due to the connection of South-North Korea and modernization of rolling stock and ancillary equipment have certainly contributed to the technological development of Korean Railroad. Such technological advancements will provide of opportunities to participate in foreign projects that have been offered in past years. Thus, a comprehensive plan and R＆D policy is necessary to continuously raise and upgrade national competitiveness in the railroad industry.

• The Journal of Internal Korean Medicine
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• v.37 no.1
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• pp.16-25
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• 2016

Objectives: Gilgyung-tang (GGT) has been used as one of the main multi-herb formulas to treat “Peo-ong” (lung abscess). In this study, we investigated the inhibitory effects of water extracts of GGT on cell migration and invasion, two critical cellular processes that are often deregulated during metastasis, in human bladder cancer 5637 cells.Methods: Effects on cell viability were quantified using an MTT assay. To analyze the anti-metastatic effects, we conducted a wound healing migration assay, an in vitro invasiveness assay, and a measurement of the transepithelial electrical resistance (TER). The expression of protein and mRNA were measured by Western blotting and real-time polymerase chain reaction (RT-PCR), respectively.Results: GGT markedly inhibited the cell motility and invasiveness of 5637 cells within the concentration range that was not cytotoxic. The inhibitory effects of GGT on cell invasiveness were associated with tightening of the tight junctions (TJs), which was demonstrated by an increase in the TER. The RT-PCR and Western blotting results indicated that GGT decreased the levels of claudin proteins. GGT also inhibited the activity and expression of matrix metalloproteinase (MMP)-2 and -9 and simultaneously increased the levels of tissue inhibitor of metalloproteinase-1 and -2.Conclusions: Our findings suggest that GGT reduces both the migration and the invasion of 5637 cells by modulating the activity of TJs and MMPs.

• The Journal of Internal Korean Medicine
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• v.38 no.4
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• pp.419-432
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• 2017

Objectives: This study provides an evaluation of the effectiveness of acupuncture for the treatment of essential tremors (ETs) using randomized controlled trials (RCTs). Methods: Nine databases (PubMed, CINAHL, EMBASE, OASIS, NDSL, CNKI, Wanfang, J-STAGE, and CiNii) and the keywords "Essential tremor", "Benign tremor", "Familial tremor", and "Acupuncture" were used to compile RCTs that used acupuncture to treat ETs. Studies that were not RCTs, such as case studies, reviews, and essays, were excluded. The methodological quality of each RCT was assessed using the Cochrane risk-of-bias tool, and where appropriate, meta-analyses were performed. Results: Initially, 819 studies were found, but 773 were excluded after title and abstract screening. After further screening of the resulting 46 papers, eight RCTs were selected that had been published between 2003 and 2016, and the total effective rate (TER) was used as the primary evaluation method for all eight studies. It was found that the TER was significantly higher in treatment groups (83.33-96.7%) than in control groups (56.5-80.0%), and seven studies included in the meta-analysis showed positive results for acupuncture for ETs (Risk Ratio: 1.43, 95% Confidence Interval: 1.21-1.69, P<0.0001) Confidence Interval. Conclusions: This meta-analysis of clinical trials suggests that acupuncture is effective for treating ET patients; however, further studies are needed or larger populations to prove its effectiveness.

• Elastomers and Composites
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• v.48 no.4
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• pp.269-275
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• 2013

In this study, we prepared poly(ethylene-ter-1-hexene-ter-divinylbenzene) using various metallocene catalysts with trityl tetrakis(pentafluorophenyl)borate/triisobutylaluminium cocatalysts system. We tried rac-$Et(Ind)_2ZrCl_2$, rac-$SiMe_2(Ind)_2ZrCl_2$, and rac-$SiMe_2(2-Me-Ind)_2ZrCl_2$ to choose optimum metallocene catalyst, comparing with catalytic activity, molecular weight, molecular weight distribution of the terpolymers. To study the effects of chain length of high ${\alpha}$-olefins on the terpolymerization, we synthesized the terpolymers using 1-hexene, 1-octene, 1-decene or 1-dodecene. We characterized chemical composition, thermal properties, and mechanical properties of the terpolymers.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.3
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• pp.107-115
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• 1998

This paper deals with the study on injection with EPDM(Ethylene propylene dien ter polymer) the gap which narrow, long, and tubular between an ablative composite tube and a steel motor case. Small size motor assembly was designed and manufactured for man-portable air defense propulsion system. Motor assembly is consisted with steel tube, ablative composite tube and insulation rubber. Ablative composite tube was made of carbon/phenolic prepreg by rolling process and insulation rubber was made of EPDM by TPM(Trans-power molding) process. To select the insulation rubber material, we tested ablative insulation property and degradation property at first and we tested fluidity, adhesive property and hardness of EPDM rubber. Finally we designed TPM process to manufacture motor case assembly and the motor case assembly was examined by non-destructive test(X-ray).

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.1-8
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• 2020

Machine translation refers to a system where a computer translates a source sentence into a target sentence. There are various subfields of machine translation. APE (Automatic Post Editing) is a subfield of machine translation that produces better translations by editing the output of machine translation systems. In other words, it means the process of correcting errors included in the translations generated by the machine translation system to make proofreading. Rather than changing the machine translation model, this is a research field to improve the translation quality by correcting the result sentence of the machine translation system. Since 2015, APE has been selected for the WMT Shaed Task. and the performance evaluation uses TER (Translation Error Rate). Due to this, various studies on the APE model have been published recently, and this paper deals with the latest research trends in the field of APE.

• The Journal of Internal Korean Medicine
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• v.39 no.6
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• pp.1150-1167
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• 2018

Objective: The purpose of this study was to investigate the effect reducing blood pressure (BP) using Xuefuzhuyu Decoction (XFZYD) in adults with essential hypertension (EH). Method: Search engine, such as PubMed, EMBASE, Cochrane library, Web of Science, J-STAGE, CiNii, CNKI, OASIS, NDSL, KISS, RISS, and DBpia, were used. The search period was from the beginning of the search engine to June 30, 2018 and there were no limits regarding languages. The selection and extraction of literatures were performed independently by two authors. Meta-analysis was done on the total effective rate (TER), Systolic BP (SBP) and Diastolic BP (DBP). Cochrane's risk of bias (ROB) was used as the methodological quality assessment scale. Results: Twenty studies were finally selected. We observed that a combination treatment using XFZYD and an antihypertensive drug (AHD) was 5.1 times more effective in lowering BP than using AHD alone on TER. The mean differences in SBP and DBP were -10.65 mmHg (95% Confidential Interval (CI) -13.55 mmHg, -7.74 mmHg, P<0.00001), -5.92 mmHg (95% CI -7.14, -4.38, P<0.00001), respectively. Conclusion: A combination treatment using XFZYD and AHD may be more effective in reducing BP than using AHD alone. Because of the poor methodological quality of the studies conducted thus far, high-quality clinical trials will be required in the future.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.34 no.4
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• pp.71-89
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• 2021

Objectives : The purpose of this study is to evaluate the effect of Banhabaeckchulchunm a-tang(BBCT) for Benign Paroxysmal Positional Vertigo(BPPV) Methods : We searched randomized controlled trials(RCTs) which assess the effect of BB CT for BPPV through 8 electronic databases from their inception to July 2021. RevMan 5.4 was used to evaluate the risk of bias. Results : 12 RCTs with 901 subjects were included. The BBCT treatment group had significantly higher total effetive rate(TER) than the western medicine treatment group(P=0.0001), and the Dizziness Handicap Inventory(DHI) score(P=0.003), traditional chinese medicine syndrome(TCM syn.) score(P<0.00001), and Visual analog scale(VAS)(P=0.0006) were significantly lower than the western medicine treatment group. The combined treatment of BBCT and canalith repositioning procedure(CRP) group had significantly higher TER than only CRP treatment group(P=0.02), and there was no significant difference in DHI score(P=0.12). TG(P=0.006) and TC(P=0.04) were significantly lower, and ApoA1 was significantly higher(P=0.0001). There was no significant difference in LDL(P=0.24). Conclusions : These results demonstrate that BBCT could be effective for BPPV especially after CRP. However, because of limits of included studies such as high heterogeneity between the literatures, unclear risk of bias, insufficient reports of adverse events(AEs), a well-designed RCTs with a low risk of bias in more diverse countries are needed in the future.

• The Journal of Internal Korean Medicine
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• v.42 no.3
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• pp.385-402
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• 2021

Objective: This study confirms the safety and efficacy of Banhasasim-tang (BST) against cough through systematic review and meta-analysis. Methods: PubMed, Cochrane, ScienceDirect, Wiley online library, OASIS, KISS, NDSL, RISS, Science and Technology Society Village, DBpia, CNKI, J-STAGE, and CiNii were used as search engines. The search period was from the start of search engine support to June 30. 2020. And search language was not limited. Cochrane's risk of bias (RoB) tool was used to evaluate the quality of the studies. A meta-analysis of the total effective rate (TER), cough symptom score, and spirometry results was performed using the Review Manager program. Results: 6 studies were finally selected. The group using BST showed significant symptom relief, as the odds ratio (OR) value of TER was 5.56 times higher (95% CI: 3.50, 8.82, P<0.0001) compared to the control groups. The reported adverse effects did not occur in the intervention group. In addition, the cough symptom score and spirometry results showed that BST was more effective than Western medicine alone. Conclusion: BST can be expected to relieve cough, and it can be applied to chronic cough that is not treated with existing treatments. However, due to the low quality of the selected articles, additional high-quality RCTs will be required in the future.