• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04a
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• pp.39-40
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• 2008

We have examined post-annealing and passivation for the transparent bottom gate IGZO TFT having an inverse co-planar structure. The oxygen-vacuum two step annealing enhanced the field effect mobility up to 18 $cm^2$/Vsandthesub-threshold swing down to 0.2V/dec. However, the hysterysis and the bias stability problems could not be solved just by post-annealing. Thus, we have passivated the bottom gate IGZO TFTs with organic and inorganic materials. $Ga_2O_3$, $Al_2O_3$, $SiO_2$ and some polymer materials were effective materials for passivations. The hysterysis and the stability of the TFTs were remarkably improved by the passivations. We have manufactured the AMOLED panel with the transparent bottom gate IGZO TFT array successfully.

• Journal of electromagnetic engineering and science
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• v.18 no.1
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• pp.63-69
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• 2018

This work demonstrates attenuation effects of plasma on waves propagating in the 26.5-40 GHz range. The effect is investigated via experiments measuring the transmission between two Ka-band horn antennas set 30 cm apart. A dielectric-barrier-discharge (DBD) plasma generator with a size of $200mm{\times}100mm{\times}70mm$ and consisting of 20 layers of electrodes is placed between the two antennas. The DBD generator is placed in a $400mm{\times}300mm{\times}400mm$ acrylic chamber so that the experiments can be performed for plasma generated under various conditions of gas and pressure, for instance, in air, Ar, and He environments at 0.001, 0.05, and 1 atm of pressure. Attenuation is calculated by the difference in the transmission level, with and without plasma, which is generated with a bias voltage of 20 kV in the 0.1-1.4 kHz range. Results show that the attenuation varies from 0.05 dB/m to 9.0 dB/m depending on the environment. Noble gas environments show higher levels of attenuation than air, and He is lossier than Ar. In all gas environments, attenuation increases as pressure increases. Finally, electromagnetic models of plasmas generated in various conditions are provided.

• Journal of Korean Neurosurgical Society
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• v.61 no.4
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• pp.467-473
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• 2018

Objective : The aim of this study was to determine outcome of ischemic stroke patients in the anterior circulation treated with endovascular treatment (EVT) with intravenous thrombolysis (IVT) versus EVT alone group. Methods : A systemic literature review was performed using online database from January 2004 to January 2017. Primary outcomes were successful recanalization seen on finial angiography and good outcome at three months. Secondary outcomes were mortality and the development of symptomatic intracranial hemorrhage (S-ICH) after the procedure. A fixed effect model was used when heterogeneity was less than 50%. Egger's regression test was used to assess publication bias. Results : Five studies were included for final analysis. Between EVT with IVT and EVT alone group, successful recanalization (odds ratio [OR] 1.467, p=0.216), good clinical outcome at three months (OR 1.199, p=0.385), mortality (OR 0.776, p=0.371), and S-ICH (OR 1.820, p=0.280) did not differ significantly. Egger's regression intercept with 95% confidence interval (CI) was 1.99 (95% CI -2.91 to 6.89) in successful recanalization and -0.27 (95% CI -6.35 to 5.80) in good clinical outcome, respectively. Conclusion : The two treatment modalities, EVT with IVT and EVT alone, could be comparable in treating acute anterior circulation stroke. Studies to find specific beneficiary group for EVT alone, without primary IVT, are needed further.

• The Journal of Korean Medicine
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• v.33 no.1
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• pp.12-23
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• 2012

Objectives: This study evaluated clinical trials of acupuncture treatment for hypertension and to assess their methodology and results. Methods: Eight Korean databases and four international databases were searched for clinical trials of acupuncture treatment for hypertension up to June 2011. Study quality was assessed using the risk of bias (ROB) tool. Results: Twenty-four trials of acupuncture for hypertension were included. There were 14 randomized and 1 non-randomized controlled trials and 9 before-after studies. The most frequently used acupuncture points were zsnli (ST36), qch (LI11), fngch (GB20), snynjio (SP06), snjin (LI03) and hgu (LI04). In more than half of the studies, needle retention time was 20~30 minutes. Compared to baseline, change of blood pressure after treatment was significant in all studies. However, the results of effect on blood pressure between acupuncture and control were not consistent. Conclusions: There is insufficient evidence to suggest that acupuncture is an effective treatment for hypertension. Further well-designed clinical trials will be required to evaluate the effects and safety of acupuncture treatment for hypertension.

• The Journal of Korean Medicine
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• v.32 no.6
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• pp.30-40
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• 2011

Objectives: The purpose of this study was to determine whether gocho (苦椒) extract mesotherapy can effectively reduce weight and abdominal fat in obese patients. Methods: Forty obese participants were recruited and randomly assigned to two groups. Five participants dropped out voluntarily during the course of the study and four men were excluded from the analysis to avoid gender bias. Results are presented on a total of thirty-one women. Over an eight-week period, the treatment group (n=13) received gocho (苦椒) extract injections (100mcg/3cc) in the abdominal skin, twice per week; the control group (n=18) received normal saline injections (3cc). A mixed lidocaine and prilocaine cream (2.5%/2.5% EMLA cream) was applied before the injection. At baseline and 8 weeks, body weight, body-mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), abdominal fat, energy expenditure, and questionnaires (eating attitudes and physical activity) were evaluated in both groups. Results: Reductions in body weight (p<0.005), BMI, and WC (p<0.05) were greater in the treatment group. WHR, total fat area, and visceral fat area decreased only in the treatment group (p<0.05). Resting metabolic rate (RMR) change was correlated with weight loss only in the control group (r=-0.498, p<0.05). Before and after the treatment, there were no significant differences between the two groups in questionnaire variables (p>0.05). Conclusion: his study suggests that abdominal gocho (苦椒) extract mesotherapy might be an effective way to promote weight and abdominal fat loss in obese Korean women.

• The Journal of Pediatrics of Korean Medicine
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• v.31 no.4
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• pp.19-30
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• 2017

Objectives The study was conducted to evaluate the acupuncture treatment for burns by reviewing international randomized controlled studies and case controlled studies. Methods In the review, ten academic literature archives; NDSL, OASIS, PubMed, Cochrane library, CNKI, WANFANG, CINAHL, J-STAGE, CiNii, and EMBASE were used as the main databases to search for the randomized controlled trials or the case controlled trials about acupuncture treatment of burns using the keywords "burns AND acupuncture", "burn AND acupuncture", and "scald AND acupuncture". Results Initially, a total of 852 studies were founded except duplicate studies. 801 studies were excluded after screening of title and abstract. After reviewing 51 papers, a total of four randomized controlled trials and two case controlled trials were selected. These studies were analyzed by year, subjects, treatment intervention, evaluation criteria, treatment effect, adverse events, and 'Risk of Bias' assessment for randomized studies and non-randomized studies. From the six papers out of 51 papers those were reviewed, patients with burns were divided into two groups. The experimental group received acupuncture treatment, while the control group did not. The results of the completed studies have shown that the experimental group receiving acupuncture treatment demonstrated significant improvement compared to the control group, and there was no serious adverse events. Conclusions According to some of the studies, acupuncture in burn treatment is worth to try. However, additional well-designed randomized controlled studies will be required to justify the effectiveness of acupuncture treatment of burns.

• Tunnel and Underground Space
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• v.12 no.1
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• pp.10-18
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• 2002

Rock joint system makes a heavy effect on the behavior of rock structures. The definition of a 3D rock joint system is very important in 2D or 3D numerical analysis for the prediction of the behavior of a discontinuous rock mass. To enhance the reality of a 3D definition of rock joint system, it is essential to estimate the unbiased statistics of basic geometric attributes of rock joints. In this study, we have proposed the statistical analysis and derived the related equations for an estimation of statistics of joint size and intensity. Geometry of rock joints in 3 dimensional space can be defined by the aggregate of location, size, orientation and intensity. The dimensional limit of survey method and its data makes 3D geometric attributes probabilistic. In the estimation of statistics of joint size, we have discussed the technique to correct the bias from a dimensional limit and derived the equation of 3D joint intensity by stereological approaches.

• The Journal of Internal Korean Medicine
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• v.38 no.6
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• pp.902-916
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• 2017

Objectives: The aim of this study was to review the clinical research on antihypertensive effects of Korean herbal medicines that function by inducing diuresis. Methods: Literature searches were performed using PubMed, Cochrane, CNKI, Wanfang, Cinii, Oasis, KISS, NDSL, RISS, DBPia, with the keywords "利水", "利尿", "高血壓", "hypertension", and "lishui." The search range included only randomized controlled trials that verified the effects of Korean herbal medicine interventions on hypertension. The selected studies were assessed by risk of bias (RoB). Results: 26 reports were selected from a total of 532 identified. For these reports, meta-analysis was performed using Revman 5.3. From this analysis, it was observed that the combined treatment of Korean medicine and antihypertensive drugs had a significantly higher total effective rate (TER) and improvement in systolic blood pressure (SBP) and diastolic blood pressure (DBP) than did the use of a single antihypertensive drug. The risk ratio of TER for lowering blood pressure was 1.25. The mean differences of SBP, DBP were -19.63 mm Hg (95% confidential interval (CI), -22.45 mm Hg, -16.80 mm Hg, p<0.00001), and -5.39 mm Hg (95% CI, -7.36 mm Hg, -3.42 mm Hg, p<0.00001) respectively. The use of Korean medicine only did not improve blood pressure, as compared to the use of an antihypertensive drug. Most of items of RoB were unclear, and the methodological quality was low. Conclusions: The combination of antihypertensive drugs and Korean medical treatment can effectively improve SBP, DBP, and TER. This finding could be widely utilized in clinical practice in Korean medicine.

• Science of Emotion and Sensibility
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• v.18 no.4
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• pp.35-46
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• 2015

Prior research suggested that people generally show stronger intentions to help in-group members because people experience higher levels of empathy for those who are similar to themselves. The present research demonstrated that one's levels of cosmopolitanism would moderate the mediating role of empathy on the relationship between cultural similarities and helping intentions. In particular, it was examined how the mediator (empathy) affected the relation between cultural similarity and helping intention for participants with low to high levels of cosmopolitanism. Results indicated that participants with lower levels of cosmopolitanism showed stronger empathy as targets are more culturally similar to participants' own culture. Participants with higher levels of cosmopolitanism, however, reported the same levels of empathy regardless of targets' cultural similarity. The implications and limitations of the results were discussed.

• Journal of the Korean Society for Heat Treatment
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• v.23 no.1
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• pp.23-28
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• 2010

The cylindrical magnetron sputtering has not been widely used, although this system is useful for only certain types of applications such as fiber coatings. This paper presents electrode configurations which improved the complicacy of the target assembly by using the positive voltage power supply. It is a modified type which has a target constructed with a large cylindrical part, a conical part and a small cylindrical part. When positive voltage was applied to an anode, a stable glow discharge was established and a high deposition rate was obtained. The substrate bias current was monitored to estimate the effect of ion bombardment. As a result, it was found that the substrate current was large. With cylindrical and conical cathode magnetron sputter deposition on the surface of the substrate to prevent re-sputtering, ion impact because it can increase the effectiveness with excellent ductility and adhesion of Ti film deposition can be obtained. We board at the front end of the ground resistance of $5\;k{\Omega}$ attached to the substrate potential can be controlled easily, and Ti film deposition with excellent adhesion can be obtained. Microstructure and morphology of Ti films deposited on pure Cu wires were investigated by scanning electron microscopy in relation to preparation conditions. High level ion bombardment was found to be effective in obtaining a good adhesion for Cu wire coatings.