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Rheological Properties of Antiphlamine-S® Lotion (안티푸라민-에스® 로션의 레올로지 특성 연구)

  • Kuk, Hoa-Youn;Song, Ki-Won
    • Journal of Pharmaceutical Investigation
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    • v.39 no.3
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    • pp.185-199
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    • 2009
  • Using a strain-controlled rheometer [Advanced Rheometric Expansion System (ARES)], the steady shear flow properties and the dynamic viscoelastic properties of $Antiphlamine-S^{(R)}$ lotion have been measured at $20^{\circ}C$ (storage temperature) and $37^{\circ}C$ (body temperature). In this article, the temperature dependence of the linear viscoelastic behavior was firstly reported from the experimental data obtained from a temperature-sweep test. The steady shear flow behavior was secondly reported and then the effect of shear rate on this behavior was discussed in detail. In addition, several inelastic-viscoplastic flow models including a yield stress parameter were employed to make a quantitative evaluation of the steady shear flow behavior, and then the applicability of these models was examined by calculating the various material parameters. The angular frequency dependence of the linear viscoelastic behavior was nextly explained and quantitatively predicted using a fractional derivative model. Finally, the strain amplitude dependence of the dynamic viscoelastic behavior was discussed in full to elucidate a nonlinear rheological behavior in large amplitude oscillatory shear flow fields. Main findings obtained from this study can be summarized as follows : (1) The linear viscoelastic behavior is almostly independent of temperature over a temperature range of $15{\sim}40^{circ}C$. (2) The steady shear viscosity is sharply decreased as an increase in shear rate, demonstrating a pronounced Non-Newtonian shear-thinning flow behavior. (3) The shear stress tends to approach a limiting constant value as a decrease in shear rate, exhibiting an existence of a yield stress. (4) The Herschel-Bulkley, Mizrahi-Berk and Heinz-Casson models are all applicable and have an equivalent validity to quantitatively describe the steady shear flow behavior of $Antiphlamine-S^{(R)}$ lotion whereas both the Bingham and Casson models do not give a good applicability. (5) In small amplitude oscillatory shear flow fields, the storage modulus is always greater than the loss modulus over an entire range of angular frequencies tested and both moduli show a slight dependence on angular frequency. This means that the linear viscoelastic behavior of $Antiphlamine-S^{(R)}$ lotion is dominated by an elastic nature rather than a viscous feature and that a gel-like structure is present in this system. (6) In large amplitude oscillatory shear flow fields, the storage modulus shows a nonlinear strain-thinning behavior at strain amplitude range larger than 10 % while the loss modulus exhibits a weak strain-overshoot behavior up to a strain amplitude of 50 % beyond which followed by a decrease in loss modulus with an increase in strain amplitude. (7) At sufficiently large strain amplitude range (${\gamma}_0$>100 %), the loss modulus is found to be greater than the storage modulus, indicating that a viscous property becomes superior to an elastic character in large shear deformations.

Extracting Building Boundary from Aerial LiDAR Points Data Using Extended χ Algorithm (항공 라이다 데이터로부터 확장 카이 알고리즘을 이용한 건물경계선 추출)

  • Cho, Hong-Beom;Lee, Kwang-Il;Choi, Hyun-Seok;Cho, Woo-Sug;Cho, Young-Won
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.2
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    • pp.111-119
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    • 2013
  • It is essential and fundamental to extract boundary information of target object via massive three-dimensional point data acquired from laser scanner. Especially extracting boundary information of manmade features such as buildings is quite important because building is one of the major components consisting complex contemporary urban area, and has artificially defined shape. In this research, extended ${\chi}$-algorithm using geometry information of point data was proposed to extract boundary information of building from three-dimensional point data consisting building. The proposed algorithm begins with composing Delaunay triangulation process for given points and removes edges satisfying specific conditions process. Additionally, to make whole boundary extraction process efficient, we used Sweep-hull algorithm for constructing Delaunay triangulation. To verify the performance of the proposed extended ${\chi}$-algorithm, we compared the proposed algorithm with Encasing Polygon Generating Algorithm and ${\alpha}$-Shape Algorithm, which had been researched in the area of feature extraction. Further, the extracted boundary information from the proposed algorithm was analysed against manually digitized building boundary in order to test accuracy of the result of extracting boundary. The experimental results showed that extended ${\chi}$-algorithm proposed in this research proved to improve the speed of extracting boundary information compared to the existing algorithm with a higher accuracy for detecting boundary information.

From Hiroshima to Fukushima: Nuclear and Artist Response in Japan (히로시마에서 후쿠시마까지, 핵과 미술가의 대응)

  • Choi, Tae Man
    • The Journal of Art Theory & Practice
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    • no.13
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    • pp.35-71
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    • 2012
  • The purpose of this essay is to examine the responses of artists on nuclear experiences through an analysis of the nuclear images represented in contemporary Japanese art. Japan has previously as twice experienced nuclear disaster in 20th century. The first atomic bombs were dropped in 1945 as well as the 5th Fukuryumaru, Japanese pelagic fishing boat, exposed by hydrogen bomb test operated by the US in 1954 nearby Bikini atoll. Due to Tsunami taken place by the great earthquake that caused the meltdown of Fukushima Nuclear Power Plant in March 2010, Japan is being experienced a nuclear disaster again. Despite practical experiences, comtemporary Japanese art has avoided the subject of nuclear disasters since the end of the Asia-Pacific War for a variety of reasons. Firstly, GHQ prohibited to record or depict the terrible effect of atomic bomb until 1946. Secondly, Japanese government has tried to sweep the affair under the carpet quite a while a fact of nuclear damage to their people. Because Japan has produced numerous war record paintings during the Second World War, in the aftermath of the defeated war, most of Japanese artists thought that dealing with politics, economics, and social subject was irrelevant to art as well as style of amateur in order to erase their melancholic memory on it. In addition, silence that was intended to inhibit victims of nuclear disasters from being provoked psychologically has continued the oblivion on nuclear disasters. For these reasons, to speak on nuclear bombs has been a kind of taboo in Japan. However, shortly after the atomic bomb dropped on Hiroshima, the artist couple Iri and Toshi Maruki visited to ruin site as a volunteer for Victim Relief. They portrayed the horrible scenes of the legacy of nuclear bomb since 1950 based on their observation. Under the condition of rapid economical growth in 1960s and 1970s, Japanese subculture such as comics, TV animations, plastic model, and games produced a variety of post apocalyptic images recalling the war between the USA and Japanese militarism, and battle simulation based on nuclear energy. While having grown up watching subculture emerged as Japan Neo-Pop in 1990s, New generation appreciate atomic images such as mushroom cloud which symbolizes atomic bomb of Hiroshima. Takashi Murakami and other Neo-Pop artists appropriate mushroom cloud image in their work. Murakami curated three exhibitions including and persists in superflat and infantilism as an evidence in order to analyze contemporary Japanese society. However, his concept, which is based on atomic bomb radiation exposure experience only claimed on damage and sacrifice, does not reflect Japan as the harmer. Japan has been constructing nuclear power plants since 1954 in the same year when the 5th Fukuryumaru has exposed until the meltdown of Fukushima Nuclear Plant although took place of nuclear radiation exposures of Three Mile and Chernobyl. Due to the exploding of Fukushima Nuclear Power Plant, Japan reconsiders the danger of nuclear disaster. In conclusion, the purpose of this paper may be found that the sense of victim which flowed in contemporary art is able to inquire into the response of artist on the subject of nuclear as well as the relationship between society, politics, culture, and modern history of Japan and international political situation.

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Electrochemical Characteristic on Lithium Intercalation into the Interface between Organic Electrolyte and Amorphous WO3 Thin Film Prepared by e-beam Evaporation Method (e-beam 증발법으로 제조된 비정질 WO3박막과 전해질 계면으로 삽입되는 리튬의 층간 반응에 관한 전기화학적 특성)

  • Min, Byoung-Chul;Sohn, Tae-Won;Ju, Jeh-Beck
    • Applied Chemistry for Engineering
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    • v.8 no.6
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    • pp.1022-1028
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    • 1997
  • This work was performed to study the characteristics of electrochemical intercalation reactions occurring at the interface between the organic electrolyte and tungsten trioxide thin film (thickness of $4000{\AA}$) prepared by e-beam evaporation method as cathodically coloring oxide with regard to the electrochromism by the intercalating reactions of the lithium cation in the 1M $LiClO_4/PC$ organic solution. The characteristics of electrochemical intercalation reactions were investigated by various DC electrochemical methods such as cathodic Tafel polarization test, multiple and the single sweep cyclic voltammetry and the coulomety titrations method. The surfaces of thin films were observed with the patterns of X ray diffraction after the coloring and bleaching reactions. In comparison with the previous results that $WO_3$ thin film intersely detached from the surface of electrode when the hydrogen cation was intercalated into $WO_3$ thin film in the o.1N $H_2SO_4$ aqueous solution, the intercalation reaction of lithium cation into $WO_3$ thin film in the 1M $LiClO_4/PC$ organic solution was shown that the stable bleaching and coloration was appeared within 1.0V of the applied overpotential. When the overpotential of electrochromic reaction for lithium cation in the 1M $LiClO_4/PC$ organic solution had been applied up to 1.5V, the accumulation phenomenon of lithium in amorphous $WO_3$ thin film layer occurred because the inserted lithium into amorphous $WO_3$ thin layer for coloring process was not fully removed from the thin layer to the electrolyte during bleaching process. It was found that there is a limitation of applied overpotential for coloring process by the reduction of the current densities of bleaching and coloration after few number of coloring and bleaching cycles.

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Stand Structure and Sapling Growth Characteristics of Korean Red Pine Stands Regenerated by the Seed Tree Method (소나무 모수림 시업지의 임분구조 및 치수생육특성)

  • Lee, Daesung;Choi, Jungkee
    • Journal of Korean Society of Forest Science
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    • v.110 no.4
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    • pp.678-688
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    • 2021
  • This study was conducted to provide growth characteristics and stand information in preparation for natural regeneration method and silvicultural treatment of seed tree method in Korean red pine stands by using the field inventoried data 18 years after the seed tree regeneration method in 2001 and analyzing the stand and sapling characteristics. The study area was located in the Research Forest of Kangwon National University, Chuncheon-si, Gangwon-do. In November 2018, we collected tree measurement factors, such as diameter at breast height (DBH), height, crown class, stem quality, tree age, and annual height increment on the established plots. We calculated the basal area, volume, height-diameter ratio (HD ratio), and additional stand density variables such as the relative density and %stocking to analyze the managed stands. The number of mother trees was 58 trees/ha, with a 17.7% stocking level, whereas the number of saplings was 2,330 trees/ha, with a 79.0% stocking level. In germination, the age distribution of saplings ranged from 2001 to 2007, with most belonging to 15-16 years. The development condition of saplings was 10 cm in DBH and 8 m in height. DBH and height were higher as the crown class is more dominant, and this difference was statistically significant in the analysis of variance and Duncan's multiple comparison test (p<0.0001). HD ratio ranged mostly between 80% and 90%, and more than 95% of sapling stems were of high quality, with a straight, unbroken top, non-sweep, and non-diseased stem. On average, the annual height increment of saplings was 21.9 cm at 1 year, 43.3 cm at 5 years, 54.3 cm at 10 years, and 64.3 cm at 15 years. The overall height growth with age increased smoothly. According to the analysis of covariance, the annual height growth by crown class differed significantly. The regression analysis parameters revealed that annual height growth increased with age and dominant crown class.