• Title/Summary/Keyword: I-V Characteristic

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A Study on the Traditional Cosmetology Culture (우리나라 전통(傳統) 화장문화(化粧文化)에 관(關)한 연구(硏究))

  • Lee, Kyung-Ja;Song, Min-Jung
    • Journal of the Korean Society of Costume
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    • v.17
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    • pp.221-245
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    • 1991
  • The purpose of the study is to search for the existene mode of the modern cosmetology by not only understanding generally but also looking into the fundamental mental base and the aesthetic senses reflected in the literatuers and remans concerned with the traditional Korean cosmetology from anient times to modern times (1910). What are characteritic of in the systemetic study are summarized as follows : Chapter I The purposes and methods are systematized and the scop of study is specified. Chapter II The definition of cosmetology and osmetic indicates that the traditional cosmetology is a sort of whole deoration with costume. Chapter III It can hypothesized that since the Koreans were the northern nomadic tribe, in the beginning the cosmetology might have had a practical usage to protect themselves from the cold weather, and then gradually become to have a decoration meaning, and finally, with the development of various social culture, undergone the transition reflecting some characteristic of each era. Chapter IV While the female cosmetology had been much likely to accomodate the spirit of the times under the male, most of the male cosmetology had been done as a means to exhibit his social position, the tendency which had been prominent in the Yi dynasty. Chapter V Sinece beauty kits which were made of raw materials had been selg-supplying only to meet the small demand, their size were relatively small and had been given a menaing of a luchy omen or exorcism. Chapter VI Buddhism introduced bathing and incense, Confucianistic view of womanhood differentiated the cosmetology between Kissang and daughters of respectable citizens, and thin make-up was recomended. In addition, there many thoughts to have influence on the traditional cosmetology culture : body-and-soul unity, exorcism, naturalism, and short-lived beauty. Chapter VII Since the on-going movement of makeing use of the traditional cosmetic materials in order to apply to modern cosmetic may be a king of counter-vertical cultural phenomena to incorporate our own tradition with the modern cosmetology culture efficiently, the hope is that the findings of the study may contribute to the said efforts. In short, the study on the traditional cosmetology culture may be heloful in Looking into the existence of the modern cosmetology through its clarification of the nature of the traditional cosmetology culture.

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Petrochemistry on igneous rocks in the Mt. Mudeung area (무등산 지역에 분포하는 화성암류의 암석화학)

  • 김용준;박재봉;박병규
    • The Journal of the Petrological Society of Korea
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    • v.11 no.3_4
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    • pp.214-233
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    • 2002
  • Igneous rocks of Mt. Mudeung area are composed of Pre-Cambrian granite gneiss, Triassic hornblende-biotite granodiorite, Jurassic quartz diorite and Cretaceous igneous rocks. The Cretaceous igneous rocks consist of volcanic rocks (Hwasun andesite, Mudeung-san dacite and Dogok rhyolite) and granitic rocks (micrograpic granite and quartz porphyry). Major elements of the Cretaceous igneous rocks represent calc-alkaline rock series and correspond to a series of differentiated products from cogenetic magma. Igneous activity of Mt. Mudeung area started from volcanic activity, and continued to intrusive activity at end of the Cretaceous. In chondrite normalized REE pattern, most of igneous rocks of Mt. Mudeung area show similar pattern of Eu (-) anomaly. This is a characteristic feature of granite in continental margin by tectonic movement. Variation diagrams of total REE vs. La/Yb V vs. SiO$_2$ indicate differentiation and magnetite fractionation sequential trend of Hwasun andesite longrightarrowMudeungsan dacitelongrightarrowquartz porphyry. In mineral composition of these igneous rocks in mt. Mudeung area, composition of plagioclase and biotite coincidence with variation of whole rock composition, and emplacement and consolidation of magma is about 15 km (about 4.9 Kbar) in Jurassic quartz diorite and 2.0~3.2 km (0.6~1.0 Kbar) in Triassic hornblende-biotite granodiorite used by amphibolite geobarometer. Parental magma type of these granitic rocks of nt. Mudeung area corresponds to VAG field in Pearce diagram, and I-type in ACF diagram.

A Study on the Objects Arrangement of Display Panel and the Cognitive Accuracy under the Virtual Reality Evaluation Tool (가상현실 기법을 적용한 평가도구를 활용한 계기반 배치 및 인지 정확도에 관한 연구)

  • Kim, Sun-young;Yu, Seung-dong;Park, Peom
    • Korean Journal of Cognitive Science
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    • v.11 no.1
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    • pp.1-8
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    • 2000
  • Most of the important visual information is presented to driver through the display panel that is related to the vehicle. If display panel is designed with the c consideration of driver's visibility, drivers can get broad visual field and visual I information related to vehicle promptly and exactly during driving situation. Therefore display panel has direct relationship with the driver's task performance and it can be considered as an important device that affects the driver-automotive interaction. Many r researches about shape, characteristic and color of display panel have been performed, but not sufficient in this country Nowadays most of vehicles has an analog type display. but its shape and arrangement a are various without any definite standards about position. Therefore. experiments using evaluation tool (VISVEC System) were conducted to inquire the driver's preference on the major objects arrangement of display panel (speedometer. tachometer. fuel meter. and t thermometer) and to ascertain the factors that have an effect on drivers according to the objects position of the display panel The experiment results showed that there was no correlation between the arrangement c characteristics preferred by subjects and the cognitive accuracy but the cognition of V visual information more easy when the each major object has its area.

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A Study on the High Temp. Tensile Properties of B1914 Ni-base Superalloy According to Crystal Structures of Poly-, Directionally Solidified- and Single Crystal Casts (Ni기 초합금 B1914의 다결정, 방향성 및 단결정 주조구조에 따른 고온 인장 특성 연구)

  • An, Seong-Uk;Jang,Yong-Seok;Yun, Dong-Han;Im, Ok-Dong;Larionov, V.;Grafas, I.;Jin, Yeong-Hun;Lee, Jae-Hun;Seo, Dong-Lee;O, Je-Myeong;Lee, Sang-Jun;Lim, Dae-Soon
    • Korean Journal of Materials Research
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    • v.8 no.9
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    • pp.831-836
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    • 1998
  • The B1914 Ni-base superalloy was manufactured according to crystal structures of poly-, directionally solidified- and single crystals. We observe deformation as type of different crystal structure from room to high temperature. Specimens are controled by cooling rate and thermal gradient and then heat treatment in vacuum and then cooling with Ar gas. Different crystal structure has different stress-strain characteristic. At $600^{\circ}C$, yield strength and ultimate strength is increased single-, directionally solidified- and poly crystals in order.

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CHARACTERISTICS OF HETEROEPITAXIALLY GROWN $Y_2$O$_3$ FILMS BY r-ICB FOR VLSI

  • Choi, S.C.;Cho, M.H.;Whangbo, S.W.;Kim, M.S.;Whang, C.N.;Kang, S.B.;Lee, S.I.;Lee, M.Y.
    • Journal of the Korean institute of surface engineering
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    • v.29 no.6
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    • pp.809-815
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    • 1996
  • $Y_2O_3$-based metal-insulator-semiconductor (MIS) structure on p-Si(100) has been studied. Films were prepared by UHV reactive ionized cluster beam deposition (r-ICBD) system. The base pressure of the system was about $1 \times 10^{-9}$ -9/ Torr and the process pressure $2 \times 10^{-5}$ Torr in oxygen ambience. Glancing X-ray diffraction(GXRD) and in-situ reflection high energy electron diffracton(RHEED) analyses were performed to investigate the crystallinity of the films. The results show phase change from amorphous state to crystalline one with increasingqr acceleration voltage and substrate temperature. It is also found that the phase transformation from $Y_2O_3$(111)//Si(100) to $Y_2O_3$(110)//Si(100) in growing directions takes place between $500^{\circ}C$ and $700^{\circ}C$. Especially as acceleration voltage is increased, preferentially oriented crystallinity was increased. Finally under the condition of above substrate temperature $700^{\circ}C$ and acceleration voltage 5kV, the $Y_2O_3$films are found to be grown epitaxially in direction of $Y_2O_3$(1l0)//Si(100) by observation of transmission electron microscope(TEM). Capacitance-voltage and current-voltage measurements were conducted to characterize Al/$Y_2O_3$/Si MIS structure with varying acceleration voltage and substrate temperature. Deposited $Y_2O_3$ films of thickness of nearly 300$\AA$ show that the breakdown field increases to 7~8MV /cm at the same conditon of epitaxial growing. These results also coincide with XPS spectra which indicate better stoichiometric characteristic in the condition of better crystalline one. After oxidation the breakdown field increases to 13MV /cm because the MIS structure contains interface silicon oxide of about 30$\AA$. In this case the dielectric constant of only $Y_2O_3$ layer is found to be $\in$15.6. These results have demonstrated the potential of using yttrium oxide for future VLSI/ULSI gate insulator applications.

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Study on the Long-term Reliability of Solar Cell by High Temperature & Humidity Test (고온고습 시험을 통한 태양전지의 장기 신뢰성에 관한 연구)

  • Kang, Min-Soo;Jeon, Yu-Jae;Kim, Do-Seok;Shin, Young-Eui
    • Journal of Energy Engineering
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    • v.21 no.3
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    • pp.243-248
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    • 2012
  • In this study, The report analysed the characteristics of power drop and damage of surface in solar cell through high temperature and humidity test. The solar cells were tested during the 1000hr in $85^{\circ}C$ temperature and 85% humidity conditions, that excerpted standard of PV Module(KS C IEC-61215). An analysis of the cell surface through EL(Electroluminescence), the cell has partly change of surface in yearly. Single-crystalline Solar cell efficiency is decreased from 17.7% to 15.6% and decreasing rate is 11.9%. On the other hand, Poly-crystalline Solar cell efficiency is decreased from 15.5% to 14.0% and decreasing rate is 9.3%. A comparison of the fill factor for analysis of electro characteristic in yearly, Single-crystalline Solar cell efficiency is decreased from 78.7% to 78.1% and decreasing rate is 4.7%. On the other hand, Poly-crystalline Solar cell efficiency is decreased from 78.1% to 76.7% and decreasing rate is 1.8%. Single-crystalline has more bigger power drop than poly-crystalline by the silicon purity and silicon atom arrangement. Also, FF decreasing rate has more bigger drop than efficiency decreasing rate for the reason that the damage of surface by exterior environmental factor is the more influence in cell than other reason that is decreasing FF by damage of p-n junction.

Alterations of Cerebral Metabolic Activation Following Electro-Acupuncture Stimulation on ST36 and LR3 Acu-Points in Rats (흰쥐의 족삼리 및 태충 전침자극에 따른 뇌대사활성의 변화)

  • Sohn, Young-Joo;Jung, Hyuk-Sang;Ku, Ja-Seung;Won, Ran;Kim, Yong-Suk;Park, Young-Bae;Sohn, Nak-Won
    • Journal of Acupuncture Research
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    • v.19 no.1
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    • pp.159-174
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    • 2002
  • Objective : The meridian theory in oriental medicine explains that each acu-point has a characteristic functional effect. It will be supposed that an acupuncture stimulation on different acu-point evokes different activation on different areas in the central nervous system(CNS) according to the meridian theory. On this supposition, our group tried the semi-quantitative [14C]2-deoxyglucose([14C]2-DG) autoradiography on the acupuncture stimulation to the hindlimb acu-points of Sprague-Dawley rats. Methods : A venous catheter for the intravenous administration of isotope was equipped in the right external jugular vein on 3 days prior to the [14C]2-DG study. On the day of the study, two acupuncture needles were inserted into the ST36(Zusanli) or LR3(Taichong) on the left hindlimb. Electro-acupuncture stimulation (2 Hz, 5 ms, 1~3 mA, 15 minutes) started just before the i.v. injection of [14C]2-DG ($25{\mu}Ci/rat$). The brain and the spinal cord were removed and processed for the [14C] 2-DG autoradiography. Results : The EA stimulation on ST36 reveals over 120% metaboilc activation in Arcuate nucleus, Anterior pretectal nucleus, Dorsal cochlear nucleus, Interposed cerebellar nucleus, and Nucleus of Darkschewitsch. The EA stimulation on LR3 reveals over 120% metaboilc activation in Lateral habenula nucleus, Medial vestibular nucleus, Ventromedial thalamic nucleus, Anteroventral thalamic nucleus, Anterior cingulate cortex, Dentate gyrus, Antero cortical amygdaloid nucleus, Anterior pretectal nucleus, and Dorsal tegmental nucleus compared with the non EA stimulation control group. Conclusion : These results demonstrate that the different acu-points evoke the different activations in brain areas. And with this functional brain mapping study, a new scientific elucidation for the basis of the acupuncture-meridian theory in oriental medicine through differences of activated area in CNS according to the each acupuncture point.

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Electric Circuit Analysis for PV Array on Short-Circuit Failure of Bypass Diode in PV Module (PV모듈의 바이패스 다이오드 단락 고장 시 태양광어레이 회로 특성분석)

  • Lee, Chung-Geun;Shin, Woo-Gyun;Lim, Jong Rok;Hwang, Hye-Mi;Ju, Young-Chul;Jung, Young-Seok;Kang, Gi-Hwan;Chang, Hyo-Sik;Ko, Suk-Whan
    • Journal of the Korean Solar Energy Society
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    • v.39 no.6
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    • pp.15-25
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    • 2019
  • As the installation of photovoltaic systems increases, fire accidents of PV system grow every year. Most of PV system fires have been reported to be caused by electrical components. The majority of fire accidents occurred in combiner box, which is presumed to be short-circuit accidents due to dustproof and waterproof failures or heat deterioration of blocking diode. For this reason, the blocking diode installation became optional by revised PV combiner regulation. In this paper, according to the revised regulation, reverse current that generated by voltage mismatch was measured and analyzed in PV array without a blocking diode. The factors that cause voltage mismatch in array are assumed to be shaded PV module and short circuit failure of bypass diode. As the result of experiment, there is no reverse current to flow under shading condition in module, but reverse current flows on the failure of bypass diode in module. According to the module's I-V characteristic curve analysis, open voltage was slightly reduced due to operation of bypass diode in shading. However, it showed that open circuit voltage has decreased significantly in the failure of bypass diode. This indicates that the difference in open voltage reduction of voltage mismatch factor causes reverse current to flow.

Dose Distribution and Characterization for Radiation Fields of Multileaf Collimateor System (방사선 입체조형치료용 다엽콜리메이터의 특성과 조직내 선량분포 측정)

  • Chu, Sung-Sil;Kim, Gwi-Eon
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.77-85
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    • 1996
  • Purpose : Multileaf collimator(MLC) is very suitable tool for conformal radio-therapy and commissioning measurements for a multileaf collimator installed on a dual energy accelerator with 6 and 10MV photons are required, For modeling the collimator with treament planning software, detailed dosimetric characterization of the multileaf collimator including the penumbra width, leaf transmission between leaf leakage and localization of the leaf ends and sides is an essential requirement. materials and Methods : Measurement of characteristic data of the MLC with 26 pair block leaves installed on CLINAC 2100C linear accelerator was performed. Low sensitive radiographic film(X-omatV) was used for the penumbra measurement and separate experiments using radiographic film and thermoluminescent dosimeters were performed to verify the dose distribution, Measured films were analized with a photodensitometer of WP700i scanner. Results : For 6 & 10 MV x-ray energies, approximately $2.0\%$ of photons incident on the multileaf collimator were transmitted and an additional $0.5\%$ leakage occurs between the leaves. Localizing the physical end of the leaves showed less than 1mm deviation from the $50\%$ decrement line and this difference is attributed to the curved shaped end on the leaves One side of a sin히e leaf corresponded to the $50\%$ decrement line, but the opposite face was aligned with a lower value. This difference is due to the tongue and groove used to decrease between leaf leakage. Alignment of the leaves to form a straight edge resulted larger penumbra at far position from isocenter as compare with divergent alloy blocks. When the MLC edge is stepped by sloping field, the isodose lines follow the leaf pattern and Produce scalloping isodose curves in tissue. The effective penumbra by 45 degree stepped MLC is about 10mm at 10cm depth for 6MV x-ray. The difference of effective penumbra in deep tissue between MLC and divergent alloy blocks is small (5mm). Conclusion : Using the characteristic data of MLC, the MLC has the clinlical acceptability and suitability for 3-D conformal radiotherapy except small field size.

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NEAR-INFRARED VARIABILITY OF OPTICALLY BRIGHT TYPE 1 AGN (가시광에서 밝은 1형 활동은하핵의 근적외선 변광)

  • JEON, WOOYEOL;SHIM, HYUNJIN;KIM, MINJIN
    • Publications of The Korean Astronomical Society
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    • v.36 no.3
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    • pp.47-63
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    • 2021
  • Variability is one of the major characteristics of Active Galactic Nuclei (AGN), and it is used for understanding the energy generation mechanism in the center of AGN and/or related physical phenomena. It it known that there exists a time lag between AGN light curves simultaneously observed at different wavelengths, which can be used as a tool to estimate the size of the area that produce the radiation. In this paper, We present long term near-infrared variability of optically bright type 1 AGN using the Wide-field Infrared Survey Explorer data. From the Milliquas catalogue v6.4, 73 type 1 QSOs/AGN and 140 quasar candidates are selected that are brighter than 18 mag in optical and located within 5 degree around the ecliptic poles. Light curves in the W1 band (3.4 ㎛) and W2 band (4.6 ㎛) during the period of 2010-2019 were constructed for these objects by extracting multi-epoch photometry data from WISE and NEOWISE all sky survey database. Variability was analyzed based on the excess variance and the probability Pvar. Applying both criteria, the numbers of variable objects are 19 (i.e., 26%) for confirmed AGN and 12 (i.e., 9%) for AGN candidates. The characteristic time scale of the variability (τ) and the variability amplitude (σ) were derived by fitting the DRW model to W1 and W2 light curves. No significant correlation is found between the W1/W2 magnitude and the derived variability parameters. Based on the subsample that are identified in the X-ray source catalog, there exists little correlation between the X-ray luminosity and the variability parameters. We also found four AGN with changing W1-W2 color.