• The Transactions of the Korean Institute of Power Electronics
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• v.16 no.3
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• pp.209-218
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• 2011

In low voltage high current applications such as fuel cells the current-fed DC-DC converter which has small ripple current and turn ratio is more efficient. In the applications larger than 5kW the conventional single-phase current-fed converter based on full-bridge, half-bridge or push-pull topologies has high current burden of devices such as switches, and the selection and optimized design of the devices are not easy. In this paper a three-phase active-clamped current-fed push-pull DC-DC converter suitable for high power high step-up applications is proposed. The proposed converter has reduced current burden and is suitable for wide input voltage applications due to the use of whole duty cycle range. Design methods of main components including three-phase high frequency transformers are provided, and the validity and performance of the proposed converter are proved from a 5kW prototype.

• Journal of Korean Medical classics
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• v.21 no.1
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• pp.43-62
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• 2008

After parturition, woman in childbed's health can grow worse. Because when woman in childbed gives birth, Genital organ can be damaged, and lost a lot of blood, and also consume a lot of physical strengths. So, after parturition, woman in childbed is easy to fall in disease if do not take care in health specially. So after parturition, woman in childbed should be careful in stress, sleep, food etc. This thesis described Postpartum Spasm[痙病], Oppressive Feeling and Dizziness[鬱冒], Constipation[便秘], Abdominal Pain[腹痛], Diarrhea[下利], Annoyance[煩亂] and Vomitting Sickness[嘔逆]. Postpartum Spasm[痙病]'s major symptom is rigided body. This disease corresponds to Tetanus in modem medicine, and bacterial infection is assumed for cause. By Oriental medicine, after parturition, when blood is lacking, if patient takes wind, this disease breaks out. Oppressive Feeling and Dizziness[鬱冒]'s major symptom is dizzy head and gloomy eye. After parturition, when blood is lacking, if patient sweats too much and take cold, this disease breaks out. After parturition, if patient consumes a lot of resins of human body, Constipation[使秘] breaks out. There are four causes to Abdominal pain[腹痛]. First, due to deficiency and cold treats by Danggwisaenggangyangyuktang(當歸牛薑羊肉湯). Second, due to stagnation of Gi(氣) treats by Jisiljakyaksan(枳實芍藥散). Third, due to blood stasis treats by Ha-eohyeoltang(下瘀血湯). Fourth, due to lochiorrhea treats by Daeseunggitang(大承氣湯). After parturition, Annoyance[煩亂] and Vomitting Sickness[嘔逆] due to fever of difficiency treat by Jukpidaehwan(竹皮大丸). After parturition, Febrile diarrhea[熱性下利] treats by Baekduonggagamchoagyotang(白頭翁加甘草阿膠湯). This disease is similar with present Bacillary Dysentery. After parturition, Exteroceptive disease due to taking wind treats by Yangdaltang. Due to wind and fever treats by Jukyeoptang(竹葉湯).

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.107-112
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• 2008

In the case of the deep reservoirs like the gas reservoirs in the East-sea, it is often difficult to observe AVO responses in CMP gathers. Because the reservoir becomes more consolidated as its depth deepens, P-wave velocity does not decrease significantly when the pore fluid is replaced by the gas. In this study, we analyzed the effects of Poisson's ratio difference on AVO response with a variety of Poisson's ratios for the upper and lower layers. The results show that, as the difference in Poisson's ratio between the upper and lower layers decreases, the change in the reflection amplitude with incidence angle decreases. To consider the limitation of AVO responses shown in the gas reservoir in East-sea, the velocity model was made by simulation Gorae V structure with seismic data and well logs. The results of comparing AVO responses observed from the synthetic data with theoretical AVO responses calculated by using material properties show that the amount of the change in reflection amplitude with increasing incident angle is very small when the difference in Poisson's ratio between the upper and lower layers is small. In addition, the characteristics of AVO responses were concealed by noise or amplitude distortion arisen during preprocessing. To overcome such limitations of AVO analysis of the data from deep reservoirs, we need to acquire precisely reflection amplitudes in data acquisition stage and use processing tools which preserve reflection amplitude in data processing stage.

• Journal of Ginseng Culture
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• v.2
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• pp.17-26
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• 2020

Ginseng, also known as Insam, has solidified its status as one of the supreme drugs classified as life time expansion drug since ancient times and was used as a panacea based on its pharmaceutical effectiveness. The demand for ginseng rapidly increased as the demand for ginseng, which targeted only noble class people, expanded to other social class people. Accordingly, the wild ginseng supply reached its limit due to the extinction caused by indiscriminate harvesting and the difficulty of harvesting, and thus the ginseng supply method shifted to the cultivation of high-priced ginseng rather than complicated wild ginseng foraging. Although the timing of ginseng cultivation (also called gasam) in Korea has been studied, the research on the first cultivation area has not been reported yet. In this study, we critically reviewed Korea's first ginseng cultivation site by arranging data related to ginseng cultivation, and the historical data cited here include Joseon Wangjo Sillog (The Annals of Joseon Dynasty), Imwon Gyeongjeji (The Mid-19 Century Encyclopedia Koreana on Rural Living, Edible plants and Herb Volumes), Oju Yeonmun Jangjeon Sango (An Encyclopedic Writing during the Latter Half Period of the Joseon Dynasty), Junggyeongji (The Junggyeong Town Chronicle), Jeungbo Munheon Bigo (The largest encyclopedia of Joseon Dynasty), Insamsa (The Ginseng History) and etc. As a result of data assortment and critical review, the first ginseng plantation in the Joseon Dynasty resulted in the Yeongnam region, and in Yeongnam region, I have no choice but to conclude that it is Punggi-myeon (currently Punggi-eup, Yeongju-si, Gyeongbuk).

• The Korean Journal of Petroleum Geology
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• v.11 no.1 s.12
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• pp.9-17
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• 2005

In the main target area of the block II, Targe-scale faults occur below the unconformity developed around 1 km in depth. The contrast of seismic velocity around the unconformity is generally so large that the strong multiples and the radical velocity variation would deteriorate the quality of migrated section due to serious distortion. More than 15 kinds of data processing techniques have been applied to improve the image resolution for the structures farmed from this active crustal activity. The bad and noisy traces were edited on the common shot gathers in the first step to get rid of acquisition problems which could take place from unfavorable conditions such as climatic change during data acquisition. Correction of amplitude attenuation caused from spherical divergence and inelastic attenuation has been also applied. Mild F/K filter was used to attenuate coherent noise such as guided waves and side scatters. Predictive deconvolution has been applied before stacking to remove peg-leg multiples and water reverberations. The velocity analysis process was conducted at every 2 km interval to analyze migration velocity, and it was iterated to get the high fidelity image. The strum noise caused from streamer was completely removed by applying predictive deconvolution in time space and ${\tau}-P$ domain. Residual multiples caused from thin layer or water bottom were eliminated through parabolic radon transform demultiple process. The migration using curved ray Kirchhoff-style algorithm has been applied to stack data. The velocity obtained after several iteration approach for MVA (migration velocity analysis) was used instead or DMO for the migration velocity. Using various testing methods, optimum seismic processing parameter can be obtained for structural and stratigraphic interpretation in the Block II, Yellow Sea Basin.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.6
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• pp.60-75
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• 2019

Nowadays, interest in safety of pedestrians who are relatively weak when compared with vehicles increases. Also, concern for pedestrian accidents on crosswalks increases. For these reasons, scrambled crosswalks which are considered to contribute pedestrian safety by reducing conflicts between vehicles and pedestrians are actively discussed and there are also a few intersections where they are actually installed. However, scrambled crosswalks must include all-red phase for all vehicle traffic flows, which inevitably leads to increase of lost time per cycle. Therefore, evaluation in terms of efficiency should be done before installation of scrambled crosswalks. This research suggests installation criteria for scrambled crosswalks so that it is possible to judge whether installation of scrambled crosswalks is appropriate only by surveying vehicle traffic volume and pedestrian traffic volume. This research derives optimum cycle length from signal optimization models which considers both vehicle traffic volume and pedestrian traffic volume. From this optimum cycle length, this research compares total delay time before and after installation of scrambled crosswalks. From an analysis, two research results are derived. Firstly, there is critical traffic volume above which installation of scrambled crosswalks can not efficient. Secondly, appropriate areas for installation of scrambled crosswalks are different by each signal intersection or by each signal system and those difference vary. From these results, this research suggests installation criteria for scrambled crosswalks which consists of two steps. The delay time of the pedestrians may be increased after the diagonal crosswalk is installed, but it may be desirable to install in consideration of the appropriate traffic level to ensure safety.

• Journal of the HCI Society of Korea
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• v.11 no.3
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• pp.5-12
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• 2016

The number of visually-impaired people using a smartphone is currently increasing with the help Text-to-Speech(TTS). TTS converts text data in a mobile application into sound data, and it only allows sequential search. For this reason, the location of buttons and contents inside an application should be determined carefully. However, little attention has been made on TTS service environment during the development of mobile newspaper application. This makes visually-impaired people difficult to use these applications. Furthermore, a mobile application interface which also reflects the desire of the low vision is necessary. Therefore, this paper presents a mobile newspaper interface which considers the accessibility and the desire of various visually impaired people. To this end, the proposed interface locates buttons with the consideration of TTS service environment and provides search functionality. The proposed interface also enables visually impaired people to use the application smoothly by filtering out the words that are pronounced improperly and providing the proper explanation for every button. Finally, several functionalities such as increasing font size and color reversal are implemented for the low vision. Simulation results show that the proposed interface achieves better performance than other applications in terms of search speed and usability.

• Research in Plant Disease
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• v.12 no.3
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• pp.168-177
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• 2006

Thirty-nine strains of Colletotrichum gloeosporioides and 5 strains of C. acutatum stored in Korean Agricultural Culture Collection(KACC) were re-identified based on molecular characteristics of ribosomal internal transcribed spacer(ITS) and partial $\beta$-tubulin gene and cultural characteristics on potato dextrose agar(PDA) and Benomyl-added PDA. As the results, 19 strains were identified as C. acutatum with 13 strains of group A2, 5 strains of group A3, and 1 strain of group A4. In addition, 20 strains were identified as C. gloeosporioides with 18 strains of ribosomal DNA group(RG) 4 and 2 strains of RG6. The rest were identified as C. boninense RG5(2 strains), C. coccodes RG2(2 strains), and C. dematium RG12(1 strain). Out of domestic 31 strains, 12 strains were identified as C. acutatum A2, one strain as C. acutatum A3, 14 strains as C. gloeosporioides RG4, 2 strains as C. gloeosporioides RG6, one strains as C. boninense RG5 and one strain as C. dematium RG12. We also discussed taxonomy of C. gloeosporioides and C. acutatum and composition of C. gloeosporioides/C. acutatum isolates from major crops in Korea.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.1
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• pp.69-75
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• 2002

A number of techniques may be employed to reduce the discomfort of syringe or needle for dental care. The use of topical anesthesia is one such method. Topical anesthetics are applied to alleviate pain during many clinical procedures, such as injection of local infiltration anesthetics, primary tooth extraction, X-ray taking of sensitive patients, reducing gag reflex prior to impression taking. In children, placement of a rubber dam clamp, however, may cause significant discomfort for purpose of pit and fissure sealant and preventive resin restoration(PRR). A topical anesthetic would be beneficial to aid in rubber dam placement for this purpose. It has been suggested that all intra-oral topical anesthetics are equally effective on reflected mucosa, however EMLA(an acronym for eutectic mixture of local anesthetics), which was developed in the 1980s and produces surface anesthesia of skin, has been shown to be more effective than conventional topical anesthetics when used on attached gingivae. This report is topical anesthesized 4 case by EMLA cream, who showed better effect in reducing the pain of infiltration anesthesia, extraction of deciduous teeth, rubber dam clamp placement and reducing the pain of preformed crown adaptation.

• Geophysics and Geophysical Exploration
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• v.11 no.3
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• pp.242-249
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• 2008

Recently, AVO analysis has been widely used in oil exploration with seismic subsurface section as a direct indicator of the existence of the gas. In the case of the deep reservoirs like the gas reservoirs in the East-sea, it is often difficult to observe AVO responses in CMP gathers even though the bright spots are shown in the stacked section. Because the reservoir becomes more consolidated as its depth deepens, P-wave velocity does not decrease significantly when the pore fluid is replaced by the gas. Thus the difference in Poisson's ratio, which is a key factor for AVO response, between the reservoir and the layer above it does not increase significantly. In this study, we analyzed the effects of Poisson's ratio difference on AVO response with a variety of Poisson's ratios for the upper and lower layers. The results show that, as the difference in Poisson's ratio between the upper and lower layers decreases, the change in the reflection amplitude with incidence angle decreases and AVO responses become insignificant. To consider the limitation of AVO responses shown in the gas reservoir in East-sea, the velocity model was made by simulation Gorae V structure with seismic data and well logs. The results of comparing AVO responses observed from the synthetic data with theoretical AVO responses calculated by using material properties show that the amount of the change in reflection amplitude with increasing incident angle is very small when the difference in Poisson's ratio between the upper and lower layers is small. In addition, the characteristics of AVO responses were concealed by noise or amplitude distortion arisen during preprocessing. To overcome such limitations of AVO analysis of the data from deep reservoirs, we need to acquire precisely reflection amplltudes In data acquisition stage and use processing tools which preserve reflection amplitude in data processing stage.