• Title/Summary/Keyword: Kim Yun-Gi

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Fabrication and Analysis of Thin Film Supercapacitor using a Cobalt Oxide Thin Film Electrode (코발트 산화물 박막을 이용한 박막형 슈퍼 캐패시터의 제작 및 특성평가)

  • Kim, Han-Gi;Im, Jae-Hong;Jeon, Eun-Jeong;Seong, Tae-Yeon;Jo, Won-Il;Yun, Yeong-Su
    • Korean Journal of Materials Research
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    • v.11 no.5
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    • pp.339-344
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    • 2001
  • An all solid-state thin film supercapacitor (TFSC) with Co$_3$O$_4$/LiPON/Co$_3$O$_4$ structure was fabricated on Pt/Ti/Si substrate using Co$_3$O$_4$ thin film electrode. Each Co$_3$O$_4$ film was grown by reactive dc reactive magnetron sputtering with increasing $O_2$/[Ar+O$_2$] ratio. Amorphous LiPON electrolyte film was deposited on Co$_3$O$_4$/Pt/Ti/Si in pure nitrogen ambient by using reactive rf magnetron sputtering. The electrochemical behavior of the Co$_3$O$_4$/LiPON/Co$_3$O$_4$ multi-layer structures exhibits a behavior of a bulk-type supercapacitor, even though much lower capacity (from 5 to 25 mF/$\textrm{cm}^2$-$\mu\textrm{m}$) than that of the bulk one. It was found that the TFSC showed a fairly constant discharge capacity with a constant current of 50 $\mu\textrm{A}/\textrm{cm}^2$ at the cut-off voltage 0-2V during 400 cycles. It is shown that the electrochemical behavior of the Co$_3$O$_4$/LiPON/Co$_3$O$_4$ TFSC is dependent upon the sputtering gas ratio. The capacity dependency of electrode films on different gas ratios was explained by different structural, electrical, and surfacical properties.

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The Improvement Strategy of Spatial Information Security Management System to Promote Spatial Information Industry -Focused on Production, Management, Supply Institutions of Spatial information- (공간정보산업 활성화를 위한 공간정보 보안관리체계의 개선전략 - 공간정보의 생산·관리·보급 기관을 중심으로 -)

  • Jeong, In Hun;Park, Hong Gi;Kim, Young Dan;Choi, Yun Soo
    • Spatial Information Research
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    • v.21 no.6
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    • pp.33-42
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    • 2013
  • In a long-term perspective of development of spatial information industry, security regulation, such as limiting public picture resolution of aerial photographs, needs a rational improvement. However, unplanned deregulation of spatial information could lead problematic results such as national security issues because its present security management system is not established in reasonable manner. The main purpose of this research is to suggest the improvement plan of spatial information security management system to meet the reducing security regulation in accordance with changes of political and economic condition including current national spatial information security polices and spatial information industry. From an analytical standpoint, we examined the overall aspects of legal, operation management, and technical system while we maintained especially integrated perspective of spatial information security management. Followed by investigation of spatial information security issues, as well as its regulation and policies in overseas, rational improvement plan of security management is proposed in the aspects of legal, operation management, and technical system. It is also suggested the three-step improvement plan of reducing regulation of security management system.

Landslide Risk Assessment Using HyGIS-Landslide (HyGIS-Landslide를 이용한 산사태 발생 위험도 평가)

  • Park, Jung-Sool;Kim, Kyung-Tak;Choi, Yun-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.1
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    • pp.119-132
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    • 2012
  • Recently, forest soil sediment disasters resulting from locally concentrated heavy rainfall have been occurring frequently in steep slope areas. The importance of landslide hazard map is emerging to analyze landslide vulnerable areas. This study was carried out to develop HyGIS-Landslide based on Hydro Geographic Information System in order to analyze forest soil sediment disaster in the mountainous river basin. HyGIS-Landslide is one of HyGIS components designed by considering the landslide hazard criteria of Korea Forest Service. It could show the distribution of landslide hazard areas after calculating the spatial data. In this system, the user could reset the weight of hazard criteria to reflect the regional characteristics of the landslide area. This component provided user interface that could make the latest spatial data available in the area of interest. HyGIS-Landslide could be applied to the surveyor's compensation score and it was possible to reflect the landslide risk exactly through it. Also, it could be used in topographic analysis techniques providing spatial analysis and making topographical parameters in HyGIS. Finally the accuracy could be acquired by calculating the landslide hazard grade map and landslide mapping data. This study applied HyGIS-Landslide at the Gangwon-do province sample site. As a result, HyGIS-Landslide could be applied to a decision support system searching for mountainous disaster risk region; it could be classified more effectively by re-weighting the landslide hazard criteria.

Break Point Chlorination (BPC) Characteristics for Heavy Metals Removal in Plating Wastewater Treatment (염소산화공정을 이용한 도금폐수의 중금속 제거 특성)

  • Jung, Byung-Gil;Lee, Seung-Won;Yun, Kwon-Gam;Jung, Jin-Hee;Kim, Jeong-Woong;Choi, Young-Ik
    • Journal of Environmental Science International
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    • v.29 no.11
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    • pp.1055-1064
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    • 2020
  • In this research, heavy metals and T-P removal characteristics of plated wastewater are derived using BPC(Break Point Chlorination) process. AA sedimentation pond outflow(Influence) was evaluated for the removal efficiency of heavy metal(Ni) and T-P at a reaction time of 25 minutes by NaOCl input volume(9, 11, 13 and 15 mL). In the case, the higher the NaOCl input volumes, the higher the ORP values were maintained and the higher the removal efficiency tended to be. On the other hand, T-P was judged to have a low relationship between the ORP value and the removal efficiency. In addition, the efficiency of removal heavy metals and T-P in the plated wastewater by injecting 10 mL, 15 mL, 20 mL and 25 mL NaOCl, increased as the amount of NaOCl injected increased, the amount of NaOH input for pH increased. It was found that suspended solid in effluence also increased. It was also observed that the color of the plating wastewater changed from yellowish green to green to charcoal gray to black as the amount of NaOCl injected increased. Treatment characteristics of the reaction time, the longer the reaction time with the substance to be treated after the input of NaOCl, the more the heavy metal removal efficiency tended to increase. Through XRF analysis of the sludge, the constituents in the sludge such as NaCNO, CNCl, Na3PO4, CrO4, 2Na2CrO4 and 2NaNO3 will be analyzed in detail, and the mechanisms of the reaction between the plated wastewater and the complex compound will be elucidated.

A Study on pH Reduction of Recycled Aggregates Using Coffee Waste and Its Crushability (커피박을 이용한 순환골재의 pH 저감 및 파쇄성 연구)

  • Lee, Young-Jae;Lee, Dong-Yun;Chen, KeQiang;Kim, Moon-Gi;Park, Sung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.32 no.11
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    • pp.21-29
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    • 2016
  • In this study, recycled aggregates crushed from waste concrete were sorted into three groups, 10-13 mm, 13-20 mm, and 20-25 mm. They were treated in different ways and then their crushability was evaluated for each treatment. Coffee waste was used for reducing their pH level. The pH of recycled aggregate was almost 11, regardless of aggregate sizes. The pH of coffee waste was nearly 5 and 10, 30, or 50 g of coffee waste was mixed with 1000 ml of distilled water and recycled aggregates. The lowest pH was about 6.2 when 50 g of coffee waste was mixed. Aggregates were treated with microwave or soaked for 1 day in vinegar (pH = 2) for neutralization reaction. Microwave treated and neutralized aggregates showed 3.3% and 6.2% higher crushing values compared to non-treated one, respectively. Neutralized treatment was more effective for crushing. In crushing tests, a sample height of 120 mm was tried, which gave 6.3% higher crushing value. A four stepped loading with each 100 kN gave 7.1% higher crushing value, compared to standard 100 mm height and 400 kN continuous loading.

Cuticle micromorphology of leaves of Quercus L. (Fagaceae) and its taxonomic implications (참나무속(Quercus L.) 식물 잎의 큐티클 미세형태의 분류학적 의미)

  • Cho, Seong-Ho;Kim, Ki-Joong;Park, Chong-Wook;Sun, Byung-Yun;Chung, Myong-Gi;Pak, Jae-Hong
    • Korean Journal of Plant Taxonomy
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    • v.38 no.4
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    • pp.405-431
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    • 2008
  • Cuticle micromorphology of 22 species of Quercus and outgroup were examined by the SEM. Twenty-two species selected each two or three species in all section of the genus Quercus. The genus Trigonobalanus and Alnus are selected as outgroups. Ten characters of the inner surface and eight characters of the outer surface of the cuticle have been described. Some characters, such as the present of papillae, arrangement of subsidiary cell, shape of anticlinal cell wall are considered important character for infrageneric classification. A parsimony analysis of 18 characters resulted in 72 most parsimonious trees with its lengths of 66 steps. The topology obtained from the analysis showed two major lineages. Subgenus Cyclobalanopsis formed one clade by 75% and subgenus Quercus formed another clade by 57% bootstrap value. Based on the cuticle morphology, the two subgenus delimitation of Camus was supported. However, sect. Erythrobalanus and sect. Cerris formed one group, and sect. Lepidobalanus formed polytomy.

Study on the Acupoints Use in Acupuncture & Moxibustion Textbook (침구학 교재에서 활용된 경혈의 분석 연구)

  • Lee, Byung-Ryul;Yang, Gi-Young;HwangBo, Min;Yoon, Young-Jin;Hwang, Sang-Moon;Lee, Byung-Wook;Chae, Han;Yim, Yun-Kyoung;Kim, Jae-Kyu
    • Journal of Acupuncture Research
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    • v.27 no.5
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    • pp.125-134
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    • 2010
  • Objectives : There has been a need for developing and establishing operational curriculum for the education of acupuncture, but defining the level and step of the acupuncture education in clinical perspectives was not thoroughly recognized so far. Methods : We analysed the usage of acupuncture points in the official textbook to recognize the most frequently used acupoints in clinical medicine. It was found that $ST_{36}$ $LI_4$ $SP_6$ $HT_7$ $LR_3$ $CV_{12}$ $BL_{23}$ $CV_6$ $BL_{20}$ $CV_4$ $LI_{11}$ $PC_6$ $KI_3$ $GB_{20}$ $GV_{20}$ $GB_{34}$ $BL_{18}$ $GV_{14}$ $BL_{17}$ $BL_{40}$ are the most frequently used 20 acupuncture points and GB(足少陽擔經), CV(任脈), ST(足陽明胃經) are the most frequently used meridians. Results : The $ST_{36}$, $GB_{34}$, $LI_{11}$ and GB(足太陽膀胱經) meridian are most frequently used for muskuloskeletal disease, $ST_{36}$, $LI_4$, $LI_{11}$ and GB(足太陽膀胱經) meridian are most frequently used for neuromuskular disease, and $ST_{36}$, $CV_{12}$, $BL_{20}$ and CV(任脈) meridian are most frequently used for the digestive system disorders. Conclusions : This study was the first systematic approach to get essential acupuncture points for the education of clinical perspectives of TKM especially for the acupuncture and moxibustion. We found that the $ST_{36}$, $GB_{34}$, $LI_{11}$ and GB(足太陽膀胱經) are the most frequently used acupuncture point and meridian. This study will be used for the development of TKM clinical curriculum.

A Study on the Sun-Moon-Stars(日月星辰) appeared in Huang Ti Nei Chin(『黃帝內經』) (『황제내경(黃帝內經)』에 나타난 일월성진(日月星辰)에 관(關)한 연구(硏究))

  • Park, Chan-Yeong;Kim, Gi-Uk;Park, Hyeon-Guk
    • The Journal of Dong Guk Oriental Medicine
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    • v.5
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    • pp.281-306
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    • 1996
  • A study on the effect of the Sun-Moon-Stars(日月星辰) in Huang Ti Nei Ching("黃帝內經") on the formation of the Yunqi theory(運氣理論) have revealed following conclusions. 1. There was a record of Stars(星辰) written by Gabgol-Character(甲骨文字) in the Yin(殷) Dynasty. But the very first documentary records of Stars(星辰) is Shu Jing("書經"). Ancient astronomy had the tendency of astrology of combined with theory of the Five Elements(五行) and finally effects the theory of formation of Huang Ti Nei Ching("黃帝內經"). 2. Shu Jing("書經") said that Junrak(錢樂) made an Armillary sphere(運天儀) in the Sung(宋) Dynasty. And in the Jin(秦) and the Han(漢) Dynasty, they already observed the stars. The Sunkiokhyung(璿機玉衡) which is machinery of star-observing, became to be called an Armillary sphere (運天儀) by the pass of times. 3. As of the theory of the Cosmos-structure(宇宙-構造論) in Ohanunhangdaeron("五運行大論"), Guiyugu(鬼兒區) announced the Hypothesis of Covering Heaven(蓋天說) but Kibak(岐伯) supported the Hypothesis of chaosheven's(蓋天說) and in the theory of atmosphere(大氣論) in Ohanunhangdaeron("五運行大論") said that the earth was in Great Empty(太虛) and it was floating in the universe by the Great Chi(大氣). 4. The knowledge about the Five stars(五星) in Huang Ti Nei Ching("黃帝內經") is presented in the section of Gemgwejineonron("金?眞言論"), Gigoupyondaeron("氣交變大論"), Youkwonjeonggidaeron("六元正紀大論").ln the method of identifying the Five stars(五星) presented the criteria of the brightness, the altitude, the colours and the orbit etc. 5. The jupiter which has twelve year's revolution cycle was the basis of determination on the Twelve constellation(12辰), the Twelve field of heaven(12次), the Twelve Houses in the ecliptic(黃道 12宮), the Twelve Earth's Branches(12支) and the Twelve fields of Earth(12分野) and also it became the origin of the duodecimals(12進法). 6. The saturn having about twenty-eight year's revolution cycle became the criterion in identifying the Twenty Eight Constellations(28宿) which was used as the coordinates of the Celestial sphere (天球). 7. By the Percussional movement(歲差運動), the position of polaris and the Vernal-Antumal equinox(春秋分点) were shifted. Therefore the ancient the Heaven Gate-Earth Door(天門-地戶) changed from the position of Sil-Byuk(室壁), Yik-Jin(翼軫). And the precisional movements brought about the concept of the WunHoyYunSe(元會運世) that is a method of dividing a period. Also the precisional movement gave three dimension(三次元) foundation interpreted the Sixty JiaZi (六十甲子) which is revolving through sixty years uniformally. 8. The Hypothesis of the Nine Houses and Eight Winds(九宮八風論) which is one field of the astrology of ancient polaris-nine Houses divination plate(太一九宮占盤) brought about the concept of deficiency and excess and the concept of the Wind Vice(風邪). In the Calendar System(曆法) presented in Huang Ti Nei Ching("黃帝內經") the tropical year of the Sun-Moon-Stars(日月星辰) and the revolution and the rotation of the earth give explanations the changes of Yin-Yang(陰陽) by the use of the ten Celestial branches(十干) and the twelve Earth branches(十二支).

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Study of Low Reflectance and RF Frequency by Rie Surface Texture Process in Multi Crystall Silicon Solar Cells (공정가스와 RF 주파수에 따른 웨이퍼 표면 텍스쳐 처리 공정에서 저반사율에 관한 연구)

  • Yun, Myoung-Soo;Hyun, Deoc-Hwan;Jin, Beop-Jong;Choi, Jong-Young;Kim, Joung-Sik;Kang, Hyoung-Dong;Yi, Jun-Sin;Kwon, Gi-Chung
    • Journal of the Korean Vacuum Society
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    • v.19 no.2
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    • pp.114-120
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    • 2010
  • Conventional surface texturing in crystalline silicon solar cell have been use wet texturing by Alkali or Acid solution. But conventional wet texturing has the serious issue of wafer breakage by large consumption of wafer in wet solution and can not obtain the reflectance below 10% in multi crystalline silicon. Therefore it is focusing on RIE texturing, one method of dry etching. We developed large scale plasma RIE (Reactive Ion Etching) equipment which can accommodate 144 wafers (125 mm) in tray in order to provide surface texturing on the silicon wafer surface. Reflectance was controllable from 3% to 20% in crystalline silicon depending on the texture shape and height. We have achieved excellent reflectance below 4% on the weighted average (300~1,100 nm) in multi crystalline silicon using plasma texturing with gas mixture ratio such as $SF_6$, $Cl_2$, and $O_2$. The texture shape and height on the silicon wafer surface have an effect on gas chemistry, etching time, RF frequency, and so on. Excellent conversion efficiency of 16.1% is obtained in multi crystalline silicon by RIE process. In order to know the influence of RF frequency with 2 MHz and 13.56 MHz, texturing shape and conversion efficiency are compared and discussed mutually using RIE technology.

Utilization of Pruning Branch of Peach tree as a Natural Dyeing Material (천연염료로서 복숭아나무 전정가지의 이용성)

  • Park Yun-Jum;Jang Hong-Gi;Kim Tae-Choon;Heo Buk-gu;Park Yong-Seo
    • Korean Journal of Plant Resources
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    • v.18 no.1
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    • pp.71-77
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    • 2005
  • This study was carried out to investigate the utilization of pruned branch of a peach tree as natural dyeing material. The dyestuff was extracted from pruned branch of a peach tree. we examined the dyeing ability on silk and cotton fabrics. The surface color of silk fabrics differed depending on mordants. E values in treatments of mordants ranged from 11.63 to 30.86 as compared to non-treatment. Dyeing properties of cotton fabrics were improved with a treatment of sulfate of iron as compared with of non-treatment. The values a increased when the slaked lime and sodium hydroxide were used as mordants, while the values b increased when copper sulfate, alum and apple vinegar were used. We investigated the surface colors of silk and cotton fabrics after washing three times. In general, the surface colors of silk and cotton fabrics between the treatments of all mordants and non-treatment were diminished by the washing. We also investigated the surface colors of silk and cotton fabrics when those were washed and treated by the light after soaking those into various pH solutions. The surface colors of silk and cotton fabrics were considerably preserved by the washing, the light and pH concentration. In conclusion, our results suggest that the dyestuffs from pruning branch of a peach tree would be useful as a natural dyeing material using the optimized conditions for silk and cotton dyeing.