• Journal of IKEEE
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• v.22 no.1
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• pp.180-184
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• 2018

Gallium oxide ($Ga_2O_3$) and silicon carbide (SiC) are the material with the wide band gap ($Ga_2O_3-4.8{\sim}4.9eV$, SiC-3.3 eV). These electronic properties allow high blocking voltage. In this work, we investigated the characteristic of $Ga_2O_3$ and 4H-SiC vertical depletion-mode metal-oxide-semiconductor field-effect transistors. We demonstrated that the blocking voltage and on-resistance of vertical DMOSFET is dependent with structure. The structure of $Ga_2O_3$ and 4H-SiC vertical DMOSFET was designed by using a 2-dimensional device simulation (ATLAS, Silvaco Inc.). As a result, 4H-SiC and $Ga_2O_3$ vertical DMOSFET have similar blocking voltage ($Ga_2O_3-1380V$, SiC-1420 V) and then when gate voltage is low, $Ga_2O_3-DMOSFET$ has lower on-resistance than 4H-SiC-DMOSFET, however, when gate voltage is high, 4H-SiC-DMOSFET has lower on-resistance than $Ga_2O_3-DMOSFET$. Therefore, we concluded that the material of power device should be considered by the gate voltage.

• The Journal of the Korea Contents Association
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• v.10 no.9
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• pp.176-189
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• 2010

This study focuses on the cultural and economic effects created by long-term TV dramas that run more than 20 years. The result of this study shows that long-lasting TV dramas have significant influence in increasing audience ratings of TV broadcasting companies. An analysis of Fuji Television's "From the Northern Country" shows that the drama's audience rating has more than doubled at the end period in comparison to that at the beginning stage. The analysis shows that long-term dramas also greatly contribute to the improvement of nation's cultural capability including contents development competence by producing media contents related professionals such as actors, actresses and dramatists. Fuji Television picked an actor and an actress for the drama and kept developing their talent and make a cultural accomplishment to produce new talents who compete with performance ability for the Japanese Entertainment Business. In addition, long lasting TV dramas appear to significantly contribute to local economy by promoting tourism industry of the areas where dramas are filmed. By introducing Hurano in Hokkaido which was the main stage of "From the Northern Country" to Japanese people for 21 years, the drama played a decisive role in building Hurano's brand power.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.95-99
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• 2008

Purpose: Even refractive error is perfectly corrected by glasses power, the glasses wearer can feel imbalance and uncomfortable by prism effects. The purpose of this study was to investigate subjective imbalance to vertical yoked prism in visually normal subjects. Methods: Visually normal 37 subjects (aged 20 to 31 y) were fully corrected by soft contact lens and worn vertical yoked prism, base up and base down 1, 2, 4, 6, 8 prism diopter(pd) at random order. A rating scale questionnaire was administered to assess quantitatively subjective imbalance to the yoked prism. The near phoria tests were done using Howell-Kim phoria card at 40 cm distance. Results: For the subjective response of imbalance, base up yoked prism was higher than base down yoked prism (t-test: t=4.67, p=0.00) in over 2 prism diopters. The frequency of subjects who feel imbalance by base up vertical yoked prism is higher for near esophoric group than for exophoric group. Conclusions: To reduce subjective imbalance caused by glasses such as dizzy, it needs to make the minimum prism effect, and base down yoked prism is more effective than base up yoked prism in prism effects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.1
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• pp.88-97
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• 2018

This study was designed to prove the effect of the Daoyin exercise therapy combined with complex korean medicine treatment on pain and function improvement of low back pain patients. A retrospective observational study. 30 low back pain patients, checked numeric rating scale(NRS) over 5, were treated with the Daoyin exercise therapy combined with complex korean medicine treatment. NRS, roland & morris disability questionnaire(RMDQ), range of motion(ROM), isokinetic muscle strength, and euroqol five demension questionnaire(EQ-5D) were checked to evaluate patients. The Daoyin exercise therapy combined with complex korean medicine treatment reduced NRS $5.67{\pm}1.40$ to $3.73{\pm}1.72$, improved RMDQ $10.33{\pm}4.91$ to $8.17{\pm}5.40$, strengthened lumbar muscle's peak torque and improved EQ-5D $0.56{\pm}0.20$ to $0.63{\pm}0.15$ and euroqol visual analogue scale(EQVAS) $46.80{\pm}19.95$ to $57.50{\pm}19.93$ but had no effect on ROM. NRS decreased significantly as the number of trials increased. No one had serious adverse reactions. As described above, the Daoyin exercise therapy combined with complex korean medicine treatment can help reducing low back pain, improving lumbar function, strengthening lumbar muscle power and stamina and improving quality of life of low back pain patients.

• Journal of Pharmacopuncture
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• v.13 no.2
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• pp.93-100
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• 2010

Background: Auricular acupressure is one of the traditional health care treatments in oriental medicine. Approximately, 30~40% of the cancer patients have said to be suffering from insomnia and half of them having chronic and severe insomnia at the same time. Insomnia caused cancer patients feel more pain, fatigue, depression and anxiety and it sometimes let the power to have the best of cancer pull down. Objective: To investigate how effective the auricular acupressure treatment to cancer patients suffering from insomnia. Methods: We recruited participants from East-West Cancer Center of Daejeon University. Finally, of the people whose age range from 20 to 75, 12 patients who got less than 40 points from the score of Oh's sleeping score (OSS) were recruited. Single-blind, randomized pilot study was performed. The treatment group received auricular acupressure treatment (AAT) on active points and the control group had received sham acupressure treatment (SAT) for five times. Sleep parameters were checked by using OSS and numeric rating scale (NRS). We checked the scale everytime, both before and after treatment. We analyzed the data statistically by using independent T-test, paired T-test and analysis of variance (ANOVA) test. (p<0.05) Results: Twelve cancer patients participated in this pilot study and there was no significant difference between control and treatment group. Only 7 of them had completed the whole treatment process, 4 patients of AAT group and 3 participants of SAT. The OSS of AAT group had increased from $34.0{\pm}4.3$ to $39.5{\pm}3.1$ and that of SAT group had increased from $38.3{\pm}3.5$ to $40.0{\pm}0.0$. There was no significant difference between them. The NRS of AAT group had increased from $6.3{\pm}2.9$, $04.8{\pm}2.1$ and that of SAT group had increased from $7.0{\pm}1.0$ to $5.0{\pm}2.6$. No significant difference was observed between them. Conclusion: Although both groups did not show significant differences, most of the experimental participants showed increasing OSS and NRS after treatments. Significant participants' number will be needed in the next study.

• The Journal of the Korea Contents Association
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• v.18 no.6
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• pp.706-718
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• 2018

This study analyzed Naver TV users' pattern of video clip watching, and analyzed the factors affecting the popularity of Naver TV's video clip. We selected 572 individual video clips that were ranked 50th in Naver TV rankings from September 10th to September 24th in 2017. We classified video clip's characteristics into several factors, including the number of likes, the number of subscriber, genre, video clip's types, and star appearances. We indexed the popularity of video clip, which implies the degree of popularity for each video clip. The results showed that the number of likes for video clips and the number of subscribers for each video clip were positively related to the popularity of video clip. Video clip's genre, video clip's type and star power positively affected the popularity of video clip. The effect of extras genre on the popularity of video clip was the lowest, followed by entertainment, music, and drama genre. but the difference among entertainment, music and drama genre was not statistically significant. Web-only video and non-broadcast video positively affected the popularity of video clip. Finally, the popularity of video clip was higher when stars appeared in the video clip.

• Korean Journal of Construction Engineering and Management
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• v.21 no.5
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• pp.64-73
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• 2020

The government announced a plan for fund support to the enterprises with high possibility of recovery and early restructuring for the enterprises with low recovery by objectifying credit assessment system. Such announcement of government could be extended to restructuring risk of middle standing enterprises with low financial soundness by establishing the basis to prepare prompt restructuring by reinforcing the basis for restructuring through capital market. This research analyzed financial soundness based on the financial evaluation of bank by selecting 10 middle standing construction companies which focused on housing business in 2019, based on such analysis result, it was confirmed that there was a high possibility of restructuring risk. This research determined that there would be a decrease in growth rate of construction industry on the whole in 2020 due to fall of economic growth rate and reinforced real estate regulation, accordingly, there's a big possibility for middle standing construction companies with paid-in capital ratio due to its low possibility of maintenance of stable credit rating. This research established KCSI assessment model by utilizing the material of a reliable research institute in order for middle standing construction companies to evade restructuring risk, and indicated risk ratio differentiated per each item through a working-level expert survey. Such research result could suggest credit risk reduction method to middle standing construction company management staffs, and prepare a basis to evade restructuring risk.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.257-266
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• 2021

Urban areas can often suffer flood damage because of the more frequent catastrophic rainfall events from climate change. Flood mitigation measures consist of (1) structural and (2) non-structural measures. In this study, the proposed method focused on operating an urban drainage system among non-structural measures. The combined inland-river operation technique estimates the inflow of pump stations based on the water level obtained from a preselected monitoring point, and the pump station expels the stored rainwater to the riverside based on those estimates. In this study, the proposed method was applied to the Mokgam drainage watershed, where catastrophic rainfall events occurred (i.e., 2010- and 2011-years), and severe flood damage was recorded in Seoul. Using the proposed method, the efficiency of flood reduction from the two rainfall events was reduced by 34.9 % and 54.4 %, respectively, compared to the current operation method. Thus, the proposed method can minimize the flood damage in the Mokgam drainage watershed by reserving the additional storage space of a reservoir. In addition, flooding from catastrophic rainfall can be prevented, and citizens' lives and property in urban areas can be protected.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.3
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• pp.363-369
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• 2014

Purpose: Three-dimensional (3D) displays are very useful in many fields, but induce physical discomforts in some people. This study is to assess symptom type and severity of asthenopia with their habitual distance corrective spectacle (HDCS) and their binocular vision corrective spectacle lenses (BVCSL) in people who feel physical discomforts. Methods: 35 adult subjects (ages $32.2{\pm}4.4$ yrs) were pre-screened out of 98 individuals to have the highest symptom/asthenopia scores following 65 minutes of 3D television viewing with HDCS. These 35 individuals were then retested symptom/asthenopia scores during they watched 3D television for 65 minutes at a distance of 2.7 m with wearing BVCSL of horizontal, vertical or base down yoked prisms. A 4-point symptom-rating scale questionnaire (0=no symptom and 3=severe) was used to assess 11 symptoms (e.g., blur, diplopia, etc.) related to visual fatigue/visual discomfort. Distance and near lateral phoria were measured using Howell phoria card and vertical phoria were measured using Maddox rod. Symptoms induced by watching 3D TV were compared between wearing HDCS and BVCSL. Results: Asthenopia in watching 3D TV with wearing BVCS was significantly lower than wearing HDCS at 5, 25, 45, and 65 minutes (all p < 0.001, paired t-tests). In only refractive error power correction power group, all asthenopia was not significantly different between HDCS and BVCSL (all $p{\geq}0.05$, paired t-tests). In prism correction groups for binocular imbalance, symptoms of asthenopia, however, was significantly lower for when wearing BVCSL than when wearing HDCS (all p < 0.05). Conclusions: Correction of phoria/vergence-based binocular vision imbalance can reduce asthenopia during 3D television viewing. An individual with binocular vision imbalance need corrected/compensated glasses with appropriate prisms prior to prolonged viewing of 3D television displays to reduce asthenopia/visual fatigue.

• Journal of IKEEE
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• v.23 no.4
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• pp.1461-1464
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• 2019

In this paper, we propose the development of embedded board for integrated radiation exposure protection fireman's life-saving alarm capable of location tracking and radiation measurement. The proposed techniques consist of signal processing unit, communication unit, power unit, main control unit. Signal processing units apply shielding design, noise reduction technology and electromagnetic wave subtraction technology. The communication unit is designed to communicate using the wifi method. In the main control unit, power consumption is reduced to a minimum, and a high performance system is formed through small, high density and low heat generation. The proposed techniques are equipment operated by exposure to poor conditions, such as disaster and fire sites, so they are designed and manufactured for external appearance considering waterproof and thermal endurance. The proposed techniques were tested by an authorized testing agency to determine the effectiveness of embedded board. The waterproof grade has achieved the IP67 rating, which can maintain stable performance even when flooded with water at the disaster site due to the nature of the fireman's equipment. The operating temperature was measured in the range of -10℃ to 50℃ to cope with a wide range of environmental changes at the disaster site. The battery life was measured to be available 144 hours after a single charge to cope with emergency disasters such as a collapse accident. The maximum communication distance, including the PCB, was measured to operate at 54.2 meters, a range wider than the existing 50 meters, at a straight line with the command-and-control vehicle in the event of a disaster. Therefore, the effectiveness of embedded board for embedded board for integrated radiation exposure protection fireman's life-saving alarm has been demonstrated.