• Title/Summary/Keyword: power of black

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The Aesthetic Characteristics of Little Black Dress through Fashion Trend from 1920 to 1990 (리틀 블랙 드레스(little black dress)의 계보(系譜)를 통(通)한 미적(美的) 특성(特性) 연구(硏究))

  • Park, Hye-Won;Kim, Yeo-Sook
    • Journal of Fashion Business
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    • v.5 no.2
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    • pp.1-14
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    • 2001
  • The purpose of this research is for confirming the aesthetics of 'little black dress' as one of the important items in contemporary women's fashion lives. Through the work, what is the aesthetic value that women really needed can be found. This research was processed by literal material with fashion photos, fashion books and articles which were related fashion trend from 1920 to 1990. The results are as follows ; The birth period of little black dress was 1920s to 1930s. Freedom and modernity was represented by little black dress. European elegance and American smartness were expressed on this item through 1950s to 1960s. In the end of 20th century, 'little black dress' has diversity just like fashion trend. As the aesthetics characteristics of little black dress, (1) contemporary woman's identity through chic and modernity (2) strong power of passing image (3) dual values of temptation and tatoo were found. Therefore this research can be useful to extent the meaning of little black dress in fashion study and to recognize contemporary women's needs.

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A Study on the Dielectric Properties and Viscoelasticity of EEA/Acetylene Black Composites (EEA/Acetylene Black 복합체의 유전특성과 점탄성에 관한 연구)

  • Lee, Kyoung-Yong;Yang, Jong-Seok;Choi, Yong-Sung;Nam, Jong-Chul;Sung, Baek-Ryong;Park, Dong-Ha;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.138-139
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    • 2005
  • To measure electrical properties and viscoelasticity of semiconducting materials in power cable, we have investigated dielectric properties and modulus of EEA/acetylene black composite showed by changing the content of acetylene black. The permittivity from experimental result was increased, while tan6 was decreased by an increment of the content of acetylene black. The modulus of specimens was increased according to a increment of a acetylene black content. And modulus was rapidly decreased at the glass transition temperature. The tan$\delta$ of specimens was decreased according to a increment of a acetylene black content.

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Investigations of Temperature Effect on the Conduction Mechanism of Electrical Conductivity of Copolymer/Carbon Black Composite

  • El Hasnaoui, M.;Kreit, L.;Costa, L.C.;Achour, M.E.
    • Applied Microscopy
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    • v.47 no.3
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    • pp.121-125
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    • 2017
  • This study deals the prediction of temperature effect on low-frequency dispersion of alternating current (AC) conductivity spectra of composite materials based on copolymer reinforced with carbon black (CB) particles. A sample of ethylene butylacrylate loaded with 13% of CB particles were prepared and investigated using the impedance spectroscopy representation in the frequency range from 40 Hz to 0.1 MHz and temperature range from $20^{\circ}C$ to $125^{\circ}C$. The dielectric constant, ${\varepsilon}^{\prime}$, and dielectric losses, ${\varepsilon}^{{\prime}{\prime}}$, were found to decrease with increasing frequency. The frequency dependence of the AC conductivity follows the universal power law with a large deviation in the high frequency region, the positive temperature coefficient in resistivity effect has been observed below the melting temperature which makes this composite potentially remarkable for industrial applications.

Avifauna on the Areas Round the Atomic Power Plant (原子力 發電所 周邊의 鳥類相)

  • Kwon, Ki-Chung
    • The Korean Journal of Ecology
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    • v.14 no.4
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    • pp.469-479
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    • 1991
  • The abundance and local distribution of birds around the three atomic power plants were studied during summer in 1998 and winter 1989. It was particularly pointed out how to determine species diversity indices, rarefaction model appeared and habitat use. During the study over 2,200 birds were censused; black-tailed gull, terek sandpipper, asian wandering tattler and australian curlew accountedfor over 76% of the observed birds in summer. Black-tailed gull, black-headed gull, mallard, ancient murrelet and tree sparrow accounted for 76% of the observed birds in winter. overall, 53 species were occurred ; 23 have been observed on yonggwang-gun, 16 used on ulchin-gun, 12 used on kyungju-gun in summer. 18 on yonggwang-gun,,14 on ulchin-gun,12 on kyungju-gun in winter respectively. These three habitats in terms of their of species richness were computed as follows; yonggwang-gun has the highest richness with an expected species number of 17.5 as the same as two season. Kyungju-gun has the lowest with an expected species number of 8.2 in summer and 11.5 in winter.

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Tidal Disruption Flares from Stars on Bound Orbits

  • Hayasaki, Kimitake;Stone, Nicholas;Loeb, Abraham
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.60.1-60.1
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    • 2013
  • We study tidal disruption and subsequent mass fallback process for stars approaching supermassive black holes on bound orbits, by performing three dimensional Smoothed Particle Hydrodynamics simulations with a pseudo-Newtonian potential. We find that the mass fallback rate decays with the expected -5/3 power of time for parabolic orbits, albeit with a slight deviation due to the self-gravity of the stellar debris. For eccentric orbits, however, there is a critical value of the orbital eccentricity, significantly below which all of the stellar debris is bound to the supermassive black hole. All the mass therefore falls back to the supermassive black hole in a much shorter time than in the standard, parabolic case. The resultant mass fallback rate considerably exceeds the Eddington accretion rate and substantially differs from the -5/3 power of time. We also show that general relativistic precession is crucial for accretion disk formation via circularization of stellar debris from stars on moderately eccentric orbits.

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Effect of CNTs on Electrical Properties and Thermal Expansion of Semi-conductive Compounds for EHV Power Cables

  • Jae-Gyu Han;Jae-Shik Lee;Dong-Hak Kim
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.36 no.6
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    • pp.603-608
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    • 2023
  • Carbon black with high purity and excellent conductivity is used as a conductive filler in the semiconductive compound for EHV (Extra High Voltage) power cables of 345 kV or higher. When carbon black and CNT (carbon nanotube) are applied together as a conductive filler of a semiconductive compound, stable electrical properties of the semiconductive compound can be maintained even though the amount of conductive filler is significantly reduced. In EHV power cables, since the semi-conductive layer is close to the conductor, stable electrical characteristics are required even under high-temperature conditions caused by heat generated from the conductor. In this study, the theoretical principle that a semiconductive compound applied with carbon black and CNT can maintain excellent electrical properties even under high-temperature conditions was studied. Basically, the conductive fillers dispersed in the matrix form an electrical network. The base polymer and the matrix of the composite, expands by heat under high temperature conditions. Because of this, the electrical network connected by the conductive fillers is weakened. In particular, since the conductive filler has high thermal conductivity, the semiconductive compound causes more thermal expansion. Therefore, the effect of CNT as a conductive filler on the thermal conductivity, thermal expansion coefficient, and volume resistivity of the semiconductive compound was studied. From this result, thermal expansion and composition of the electrical network under high temperature conditions are explained.

The Comparison of Southern White Womanhood between Langston Hughes and Richard Wright

  • Taneda, Kaori
    • English & American cultural studies
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    • v.17 no.1
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    • pp.191-206
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    • 2017
  • Langston Hughes (1902-67) and Richard Wright (1908-60) lived in almost the same era, but it is obvious that their ways of describing the people, who are manipulated by gender-based controlling images, are different. Both Wright and Hughes try to reveal how reality is disturbed by the black men's and white women's prevailing stereotypes; however, their works have very different tones. In Richard Wright's short story, "The Man Who Killed a Shadow," and Langston Hughes' poems in his early days, "Silhouette" and "The South," the stereotyped images of black masculinity and white womanhood are transformed and destroyed. While Hughes celebrates the black culture amicably, Wright depicts completely hopeless black men living in the world dominated by white supremacy. This difference is indicative of the shifting views from Harlem Renaissance to Post-Harlem Renaissance. While romantic tones can be still found in Hughes' poems, Wright subverts the power dynamics between the black man and the white woman, and completely ruins sentimentality which tends to be attached to the Southern stories in the $19^{th}$ century.

A Study on Impurities Measurement and Physical Properties of Semiconductive Shield at Power Cable (전력케이블에서 반도전 재료층의 불순물 측정 및 물성에 관한 연구)

  • 이경용;양종석;최용성;박대희
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.9
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    • pp.455-458
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    • 2004
  • In this paper, we investigated impurities content and physical properties showing by changing the content of carbon black that is semiconductive materials for underground power transmission. Specimens were made of sheet form with the three of existing resins and the nine of specimens for measurement. Impurities content of specimens was measured by ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometer), and density of specimens were measured by density meter And then specific heat (Cp) was measured by DSC (Differential Scanning Calorimetry). A ranges of measurement temperature were from $0^{\circ}[C]$ to $200^{\circ}[C]$, and heating temperature was $4^{\circ}[C/min]$. Impurities content was highly measured according to increasing the content of carbon black from this experimental result, also density was increased according to these properties. Especially impurities content values of the Al and A2 of existing resins were measured more than 4000[ppm]. Specific heat from the DSC results was decreased according to increasing the content of carbon black. Because ionic impurities of carbon black having Fe, Co, Mn, Al and Zn are rapidly passed kinetic energy increasing the number of times breaking during the unit time with the near particles according to increasing vibration of particles by the applied heat energy.

The functions & Requirements of the Semi-Conducting layer in the power cable. (전력 케이블에서 반도전층의 역할과 요구 특성)

  • Jung, Yun-Tack;Nam, Jong-Chul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.05c
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    • pp.101-105
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    • 2001
  • For high voltage XLPE power cables, semiconducting layers have been applied to prevent discharge at the interface between conductor and insulation, and/or insulation and external shielding layer. The semiconducting layers may be also effective to release electrical stress in the interface. The property of semiconducting layers are significantly related to the quality and reliability of power cables. Generally, these semiconducting layers are formed by extruding, the conductibility of the material is given by the carbon black mixed with base polymer. The life of power cables is depended on the smoothness of the interface between insulation and semiconducting layer. If the smoothness is no good, the life of power cables is shorter because the electrical stress and water tree is increased. The causes of no good smoothness are the void of the interface, the protrusions, the contaminants and impurities of the semiconducting layer. The selection and dispersion of the Carbon Black is the significant factor to determine the life of power cable in the manufacturing of semiconducting compound.

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Measurement of Impurities and Physical Properties at Semiconductive Shield of a Power Cable (전력케이블의 반도전 재료에서 불순물 및 물성 측정)

  • Lee Kyoung-Yong;Yang Jong-Seok;Choi Yong-Sung;Park Dae-Hee
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.12
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    • pp.601-605
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    • 2004
  • In this paper, we investigated ionic impurities and physical properties by change of carbon black content, which is asemiconductive material for underground power transmission. Specimens were made into sheet form with three existing resins and nine specimens for measurement. The ionic impurities of the specimens were measured using anICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometer), and the density of specimens was measured by a density meter. Specific heat (Cp) was then measured using aDSC (Differential Scanning Calorimetry). The ranges of measurement temperature were from 0[$^{\circ}C$] to 200[$^{\circ}C$], and heating temperature was 4[$^{\circ}C$/min]. Ionic impurities were measured to be high according to increases in the content of carbon black from this experimental result and density was also increased according to these properties. In particular, the impurity content values of A1 and A2, and existing resins, were measured at more than 4000[ppm]. Specific heat from the DSC results was lowered according to augmentation in the content of carbon black. The ionic impurities of carbon black containing Fe, Co, Mn, Al and Zn are forms of rapidly passed kinetic energy that increase the number of times breaking occurs during unit time with the near particles according to an increase in the vibration of particles by the applied heat energy.