• Title/Summary/Keyword: ITS활성화

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Psychological Meaning of Creation Myths: Focused on Darkness/Massa Confusa, Separation of World Parent and Creation of Land/Island (무의식의 창조성 관점으로 고찰한 창조신화: 흑암/혼돈, 천지개벽/분리, 섬/육지 창조 중심)

  • Jin-Sook Kim
    • Sim-seong Yeon-gu
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    • v.38 no.2
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    • pp.269-304
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    • 2023
  • The purpose of this paper is to present the psychological meaning of the creation myths by utilizing related myths, analysand's dreams, active imagination, and artwork to reveal the creative function of the unconscious. The creation myth is the phenomenon of projection when a new order is demanded in the chaotic phase of personal and human history. Depending on the attitude of the ego, it can be a sign of a reconstruction/alteration of consciousness or an invasion. Related literature such as Jung, von Franz, Neumann, Harding, and Edinger, domestic papers, and case reports are introduced to identify the background for this research. The psychological meaning of 'darkness' in creation myths is regarded as unconscious that is too dark to see. The Eskimo creation myth and an analysand's dreams of being blind and wandering in darkness are discussed in relation to nigredo in Alchemy. The psychological meaning of 'massa confusa' regards Uroboros, pleroma, early childhood experience, and a psychological womb in which everything is contained in one. With related myths and unconscious materials, a discussion is followed on how this realm can be a precursor of creation but also be trapped in an abyss. The psychological meaning of 'separation of world parent' is related to splitting one into two when unconscious contexts were touched before it became consciousness. Related myths, 'the world created between heaven and earth,' 'celestial being descending to the earth,' and 'the legend of relocation of a mountain,' as well as clinical material, are examined. Then this paper discusses the clinical implications of the separation of heaven and earth occurring on its own, that the creator's emotional aspects, such as loneliness and anxiety, are involved, and that delayed separation leads to the death of creatura and sudden separation leads to the death of the chaos. Then, the meaning of 'separation of world parent' is discussed in relation with separatio, the alchemical process of acquiring light/consciousness from darkness/unconsciousness. The psychological meaning of the creation of 'land/island' refers to the emergence of consciousness, the contents of the unconscious material into the realm of the ego. Related myths, such as the 'body of the monster/dragon becoming land' and analysand's dreams, are introduced, referring to the embodiment of Mercurius. This is followed by discussing related myths in creating the land to coagulatio in alchemy and utilizing creative work such as active imagination, art, music, and dance that can coagulate or concretize unconscious material in clinical approaches. Finally, myths of resurfaced land after the Flood or the complete destruction of the world in relation to the reconstruction of ego are discussed with related clinical material to show the importance of the analyst/therapist/supervisor's mental stability and capacity.

A Psychological Interpretation of Fairly Tale Mokdoryung, Son of Tree (한국민담 '목(木)도령'의 분석심리학적 해석)

  • Jin-Sook Kim
    • Sim-seong Yeon-gu
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    • v.25 no.2
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    • pp.224-264
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    • 2010
  • A brief story of the tale follows : Mokdoryung was a son of an arbor tree and a fairly. When the boy was 7-8 years old, mother-fairy returned to the sky. By using father-tree, Mokdoryung survived from the flood where he saved ants, mosquitos, and a boy with the same age. They arrived on top of the highest mountain, met an old woman with two daughters, worked as servants. With help of insects, Mokdoryung passed the trials, married to a wise daughter and 2 couples became the ancestor of the mankind. Interpretation of the tale starts with amplification of tree which symbolizes Self and Libido. As the son of the tree-spirit and a fairly from the sky, Mokdoryung is a kind of 'divine child' which represents a psychic possibility to understand archetypal nature of unconscious. Adversities of early childhood due to mother's absence regarded as necessary condition for 'divine child' to attain highest good. Flood can be compensation of absence of feminine as well as to bring a new life. The notion of father·tree becomes a kind of life-boat has to do with union of opposite(vertical phallic tree and horizontal feminine boat). Ants and mosquitoes represent upper and lower level of unconsciousness, they mediate divine power. Therefore respecting insects means respecting unconscious, and reward of insects means salvation come from unconscious. The boy saved from the flood presents emergence of psychic energy in its latent unconscious condition to create mental dynamism. The old woman is Great Mother or anima, the controller or guider of unconscious. Working as servants can be an active service for the divine marriage. Trials of separating millet from sand, and finding right direction relate to separatio, means one needs to be separated from unconscious before conunctio, union of opposite. Two sets of couple becoming ancestor of man-kind has to do with number 4 (quaternity) as well as regeneration. Although the tale includes both positive couple (Mokdoryung, wise daugther in east room). and negative couple(shadow side of Mokdoryung, step daughter in west room)as ancestors of mankind, "Good" seems to be more valued than "evil".

Review on the impact of Arctic Amplification on winter cold surges over east Asia (북극 온난화 증폭이 겨울철 동아시아 한파 발생에 미치는 영향 고찰)

  • Seong-Joong Kim;Jeong-Hun Kim;Sang-Yoon Jun;Maeng-Ki Kim;Solji Lee
    • The Korean Journal of Quaternary Research
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    • v.33 no.1_2
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    • pp.1-23
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    • 2021
  • In response to the increase in atmospheric carbon dioxide and greenhouse gases, the global mean temperature is rising rapidly. In particular, the warming of the Arctic is two to three times faster than the rest. Associated with the rapid Arctic warming, the sea ice shows decreasing trends in all seasons. The faster Arctic warming is due to ice-albedo feedback by the presence of snow and ice in polar regions, which have higher reflectivity than the ocean, the bare land, or vegetation, higher long-wave heat loss to space than lower latitudes by lower surface temperature in the Arctic than lower latitudes, different stability of atmosphere between the Arctic and lower latitudes, where low stability leads to larger heat losses to atmosphere from surface by larger latent heat fluxes than the Arctic, where high stability, especially in winter, prohibits losing heat to atmosphere, increase in clouds and water vapor in the Arctic atmosphere that subsequently act as green house gases, and finally due to the increase in sensible heat fluxes from low latitudes to the Arctic via lower troposphere. In contrast to the rapid Arctic warming, in midlatitudes, especially in eastern Asia and eastern North America, cold air outbreaks occur more frequently and last longer in recent decades. Two pathways have been suggested to link the Arctic warming to cold air outbreaks over midlatitudes. The first is through troposphere in synoptic-scales by enhancing the Siberian high via a development of Rossby wave trains initiated from the Arctic, especially the Barents-Kara Seas. The second is via stratosphere by activating planetary waves to stratosphere and beyond, that leads to warming in the Arctic stratosphere and increase in geopotential height that subsequently weakens the polar vortex and results in cold air outbreaks in midlatitudes for several months. There exists lags between the Arctic warming and cold events in midlatitudes. Thus, understanding chain reactions from the Arctic warming to midlatitude cooling could help improve a predictability of seasonal winter weather in midlatitudes. This study reviews the results on the Arctic warming and its connection to midlatitudes and examines the trends in surface temperature and the Arctic sea ice.

A Study on Historicity of 《Three Purities Album (三淸帖)》 in the Kansong Art Museum (간송미술관 소장 《삼청첩(三淸帖)》의 역사성에 대한 고찰)

  • Baik, In-san
    • Korean Journal of Heritage: History & Science
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    • v.46 no.2
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    • pp.186-205
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    • 2013
  • ${\ll}$Three Purities Album${\gg}$ in the Kansong Art Museum is an album of poems and pictures of apricot tree, orchids and bamboos drawn by Lee Jeong. Given that the poems and pictures in the album were drawn by Lee Jeong who has been recognized as a person who established the standards of ink bamboo drawings in the Joseon Dynasty, the album is highly valuable. Nevertheless, there are more values and meanings that Three Purities Album has. The production circumstances and transmission processes of Three Purities Album include the historical characteristics and meanings of the time so that it is also worthwhile as a historical material. During the Japanese Invasion of Korea in 1592, Lee Jeong was stabbed with a sword by Japanese invaders and got injured. After he suffered, he tried to make his masterpiece in his lifework and finally created Three Purities Album. For the work, Lee Jeong received memorial writings from Choi Rip, Cha Cheon-ro and Han Ho, and asked them writings. They were the best literary men in the poem and calligraphy fields at that time. Yu Geun, Lee An-nul, and Yu Mong-in made writings and poems to praise his work. Likewise, ${\ll}$Three Purities Album${\gg}$ is the 'treasure of the time' created through the participation of the best literary men at that time. Given the aspects, it is fair to say that ${\ll}$Three Purities Album${\gg}$ is not simply a personal artwork of Lee Jeong, but is a comprehensive artwork and also a cultural monument created through the skills and capabilities of the literary artists in the middle of the Joseon Dynasty. After the death of Lee Jeong, Three Purities Album was handed over to Hong Ju-won. But, during the second Manchu Invasion into Korea in 1636, the album was in danger of disappearance by fire. As of now, there are still signs of fire in it, which vividly shows the urgent situation at that time. After the second Manchu Invasion into Korea in 1636, Hong Ju-won recovered some damaged writings with the help of Yoon Shin-ji. Since then, the album had been handed down as a family treasure over the next 7 generations. It can be found in the writings by Song Si-yeol and Uh Yu-bong. Unlike the literary men who praised Three Purities Album in terms of its work when Lee Joeng was alive, they focused on the transmission courses of the album and involved persons. That seems to be because the stories and characters appearing in Three Purities Album impressed the later literary men and were meaningful to them rather than the album itself. It strongly reflected the positions of Hong Jung-gi and Hung Sang-han who asked for writings as the descendants of Hong Ju-won. That is because the traces of the persons involved in Three Purities Album are the causes for admiring their ancestors and enhancing their political legitimacy and family dignity. Therefore, in this aspect, it is possible to witness the fundamental causes of the unique artistic awareness by East Asian people who consider their historical meanings as well as the aesthetic value of artworks significant. Unfortunately, during the Japanese invasion at the end of the Joseon Dynasty, Three Purities Album was handed over to Japanese Tzuboikouso. But, fortunately, Jeon Hyeong-pil who made an effort to regain our cultural assets by investing his entire property during the Japanese Imperialism regained the album, which is now preserved in the Kansong Art Museum. ${\ll}$Three Purities Album${\gg}$ truly includes the whole processes to overcome national crises that Korean people experienced during the Japanese Invasion in 1592, the second Manchu Invasion of Korea in 1636, and the Japanese Imperialism, and it shows the sufferings of our cultural assets and the history of preservation. Also, the album shows that one artwork is able to accumulate its historical meanings in the process of transmission and thus enhances its meanings and values. ${\ll}$Three Purities Album${\gg}$ features accumulative and constant historical meanings and it is a typical case showing that an artwork is plenty of aesthetic and historical values. It is expected that this work will contribute to promoting more studies on finding historical meanings and hysteresis of artworks.

The Relationship Between the NF-${\kappa}B$ Activity and Anti-inflammatory Action of Surfactant in the Acute Lung Injury of Rats (백서의 급성폐손상에서 surfactant의 항염증작용과 호중구의 NK-${\kappa}B$ 활성과의 관계)

  • An, Chang-Hyeok;Cha, Young-Joo;Lee, Kyoung-Hee;Yoo, Chul-Gyu;Lee, Byoung-Jun;Jeong, Do-Young;Lee, Sang-Hoon;Shin, Jong-Wook;Kim, Jae-Yeol;Park, In-Won;Choi, Byoung-Whui
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.5
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    • pp.519-529
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    • 2002
  • Background : The therapeutic effects of surfactants on acute lung injury derive not only from their recruiting action on collapsed alveoli but also from their anti-inflammatory action in the alveolar sapce. This study evaluated the anti-inflammatory action of a surfactant in an acute lung injury model of rats by neutrophils were recollected from the BAL fluid and the NF-${\kappa}B$ activity of the neutrophilic nuclear protein was evaluated. Methods : Male Sprague-Dawley rats weighing approximately 300 gram were divided into 3 groups, which consisted of 6 rats respectively. In the control group, normal saline(3ml/kg) was instilled into the trachea twice with 30 minute interval. In two other groups, acute lung injury was induced by the intra-tracheal instillation of LPS(5mg/kg). Thirty minutes later, either a surfactant(ST group; 30mg/kg) or normal saline(NT group: 3ml/kg) was instilled via the trachea. Twenty-four hours after the LPS instillation, the BAL fluid was retrieved to measure the WBC count and cytokine(IL-$1{\beta}$ and IL-6) levels. The neutrophils were isolated from the BAL fluid and the nuclear protein was extracted to evaluate the NF-${\kappa}B$ activity using a eletrophoretic mobility shift assay(EMSA). Results : The WBC count of the BAL fluid of the ST group($3,221{\pm}1,914{\times}10^3/{\mu}l$) was higher than that of the control group($356{\pm}275{\times}10^3/{\mu}l$)(p<0.05) and lower than that of the NT group($5,561{\pm}1,757{\times}10^3/{\mu}l$)(p<0.05)). The BAL fluid level of IL-$1{\beta}$ from the NT group($2,064{\pm}1,082pg/ml$) was higher than those of the ST group($360{\pm}234pg/ml$)(p<0.05) and the control group(0pg/ml)p<0.05) and control group($49{\pm}62pg/ml$)(p<0.05). The NF-${\kappa}B$ activity of the neutrophilic nuclear protein in the ST group and NT group was similar. Conclusion : The surfactant, attenuates the alveolar inflammation in the acute lung injury of rats model. However, its anti-inflammatory action does no't appear to be mediated by the inhibition of NF-${\kappa}B$ activity.

The Mechanism of Interferon-$\gamma$ Induced Cytotoxicity on the Lung Cancer Cell Line, A549 (인터페론감마에 의한 A549 폐암세포주 세포독성의 기전)

  • Oh, Yeon-Mok;Yoo, Chul-Gyu;Chung, Hee-Soon;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.1
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    • pp.63-68
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    • 1996
  • Background: Interferon-$\gamma$ has various biologic effects, including antiviral effect, antitumor proliferative effect, activation of macrophage and B lymphocyte, and increased expression of major histocompatibility complex. Especially, antitumor proliferative effect of interferon-$\gamma$ has already been proved to be important in vivo as well as in vitro. And, clinical studies of interferon-$\gamma$ have been tried in lung cancer patients. However, the mechanism of antitumor effect of interferon-$\gamma$ has not yet been established despite of many hypotheses. "Necrosis" is a type of cell death which is well known to occur in the circumstances of severe stresses. In contrast, "apoptosis" is another type of cell death which occurs in such biological circumstances as embryonic development, regression of organs, and self-tolerance of lymphocytes. And, apoptosis is an active process of cell death in which cells are dying with fragmentations of their cytoplasms and nuclei. And, in the process of apoptosis the DNAs of cells are cleaved between nucleosomes by unidentified endonuclease and therefore DNAs of apoptotic cells result in a typical electrophoresis pattern known as DNA ladder pattern. Recently it has been suggested that cytotoxic effect of interferon-$\gamma$ occurs via apoptosis. To elucidate the mechanism of antitumor cytotoxic effect of interferon-$\gamma$, we microscopically observed a lung cancer cell line, A549 which was treated with interferon-$\gamma$. We observed A545 treated with interferon-$\gamma$ was dying fragmented. And so, we performed this study to find out that the mechanism of antitumor cytotoxic effect of interferon-$\gamma$ be apoptosis. Method: We treated A549, human lung cancer cell line with various concentration of interferon-$\gamma$ and quantified its cytotoxic effect of various periods, 24 hours, 72 hours and, 120 hours by MTT(dimethylthiazolyl diphenyltetrazolium bromide) bioassay. Also, after we treated A549 with 100 units/mi of interferon-$\gamma$ for 120 hours, we observed the pattern of cell death with inverted microscope and we extracted DNAs from the dead A549 cells and observed the pattern of 1.5% agarose gel electrophoresis with ethidium bromide staining. Result: 1) Cytotoxic effect of interferon-$\gamma$ on A549: For the first 24 hours, threre was little cytotoxic effect and for between 24 hours and 72 hours, there was the beginning of cytotoxic effect and for 120 hours there was increased cytotoxic effect. 2) Pattern of A549 cell death by interferon-$\gamma$: We observed with inverted microscope that A549 cells were dying fragmented. 3) DNA ladder pattern of gel electrophoresis: We observed DNA ladder pattern of gel electrophoresis of extracted DNAs from dead A549 cells. Conclusion: We concluded that the mechanism of interferon-$\gamma$induced cytotoxicity on lung cancer cell line, A549 be via apoptosis.

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The Environmental and Ecological Meaning of Bibo Landscape in Otgol Village (옻골마을 비보경관의 환경생태적 의미)

  • Jang, Byoung-Kwan;Whang, Bo-Chul
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.2
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    • pp.32-41
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    • 2008
  • An empirical study and environmental and ecological analysis were conducted on Otgol Village(a village of the Gyeongju Choi's clan in Daegu) where an enclosed pond and groves are still observed. In particular, the enclosed pond and groves and village water system were investigated from an ecological perspective. The enclosed landscape is described based on feng shui principles and the environmental and ecological significance were examined. In general, the environmental and ecological significance is very broad; however, they were analyzed in terms of the quality of life as an empirical study as follows: First, water quality was measured to investigate the improvement of continuous water system functions. In other words, water quality was measured at East Valley(resting space), West Valley(living space), the enclosed pond where the two valleys merge, and the stream that flows out of the pond. Second, the climate functions of the enclosed groves that border the village were examined. In other words, temperature was measured in two places(200m distance from the center of the groves). Third, whether or not a sound ecosystem can be sustained was investigated. In other words, landscape ecological indicators were chosen and measured. The results are as follows: First, the enclosed pond played the role of purifying water quality. While the East Valley has been popular with men for its rock walls and torrents, the West Valley has been popular with women as a living space(ex: doing the laundry). Therefore, the difference of water quality can be explained. Second, since enclosed groves are in a small village forest, they are very weak in terms of being wind proof and temperature reduction effects. Instead, they play the role of the village boundary. Third, the groves are ecologically sound considering the landscape ecological indicators and are similar to ordinary traditional rural villages. In terms of the connection of the green zone, the village groves are well connected to the village boundary wood. If the village groves are restored, in particular, they would offer a decent habitat for grove creatures. According to this study, the traditional village space was formed upon the influence of Feng Shui theories that are based on environmental and ecological principles that focus on the harmony between humans and nature. From the environmental and ecological perspective, the enclosed pond and groves are important factors in building a sustainable village. The diverse water space would help to improve water quality and increase water volume by promoting the water circulation system. In addition, the village woods would surround the village and decrease the temperature and humidity difference between winter and summer. If the groves are small and badly damaged, however, they are meaningful only in dividing the region. The overall improvement of a forestation system and botanical composition may increase the biological diversity and promote the migration of species. Otgol Village has developed an enclosed landscape to improve the village environment. In other words, a sound and refreshing living environment can be developed when the natural ecological system is well understood and properly preserved. Additionally, this traditional village planning will be the environmental and ecological method. From the perspective of environmental ecology, therefore, a traditional village is recommended.

The Role of Poly(ADP-ribose) Polymerase-1 in Ventilator-Induced Lung Injury (기계환기로 인한 급성 폐손상에서 poly(ADP-ribose) polymerase-1의 역할)

  • Kim, Je-Hyeong;Yoon, Dae Wui;Hur, Gyu Young;Jung, Ki Hwan;Lee, Sung Yong;Lee, Sang Yeub;Shin, Chol;Shim, Jae Jeong;In, Kwang Ho;Yoo, Se Hwa;Kang, Kyung Ho
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.4
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    • pp.451-463
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    • 2006
  • Background : Reactive oxygen species (ROS) take center stage as executers in ventilator-induced lung injury (VILI). The protein with DNA-damage scanning activity, poly (ADP-ribose) polymerase-1 (PARP1), signals DNA rupture and participates in base-excision repair. Paradoxically,overactivation of PARP1 in response to massive genotoxic injury such as ROS can induce cell death through ${\beta}$ -nicotinamide adenine dinucleotide ($NAD^+$) depletion, resulting in inflammation. The purpose of this study is to investigate the role of PARP1 and the effect of its inhibitor in VILI. Methods : Forty-eight male C57BL/6 mice were divided into sham, lung protective ventilation(LPV), VILI, and PARP1 inhibitor (PJ34)+VILI (PJ34+VILI) groups. Mechanical ventilator setting for the LPV group was $PIP\;15cmH_2O$ + $PEEP\;3cmH_2O$ + RR 90/min + 2 hours. The VILI and PJ34+VILI groups were ventilated on a setting of $PIP\;40cmH_2O$ + $PEEP\;0cmH_2O$ + RR 90/min + 2 hours. As a PARP1 inhibitor for the PJ34+VILI group, 20 mg/Kg of PJ34 was treated intraperitoneally 2 hours before mechanical ventilation. Wet-to-dry weight ratio and acute lung injury (ALI) score were measured to determine the degree of VILI. PARP1 activity was evaluated by using an immunohistochemical method utilizing biotinylated NAD. Myeloperoxidase (MPO) activity and the concentration of inflammatory cytokines such as tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\beta}$, and IL-6 were measured in bronchoalveolar lavage fluid (BALF). Results : In the PJ34+VILI group, PJ34 pretreatment significantly reduced the degree of lung injury, compared with the VILI group (p<0.05). The number of cells expressing PARP1 activity was significantly increased in the VILI group, but significantly decreased in the PJ34+VILI group (p=0.001). In BALF, MPO activity, $TNF-{\alpha}$, $IL-1{\beta}$, and IL-6 were also significantly lower in the PJ34+VILI group (all, p<0.05). Conclusion : PARP1 overactivation plays a major role in the mechanism of VILI. PARP1 inhibitor prevents VILI, and decreases MPO activity and inflammatory cytokines.

Global Cosmetics Trends and Cosmceuticals for 21st Century Asia (화장품의 세계적인 개발동향과 21세기 아시아인을 위한 기능성 화장품)

  • T.Joseph Lin
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.23 no.1
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    • pp.5-20
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    • 1997
  • War and poverty depress the consumption of cosmetics, while peace and prosperity encourage their proliferation. With the end of World War II, the US, Europe and Japan witnessed rapid growth of their cosmetic industries. The ending of the Cold War has stimulated the growth of the industry in Eastern Europe. Improved economies, and mass communication are also responsible for the fast growth of the cosmetic industries in many Asian nations. The rapid development of the cosmetic industry in mainland China over the past decade proves that changing economies and political climates can deeply affect the health of our business. In addition to war, economy, political climate and mass communication, factors such as lifestyle, religion, morality and value concepts, can also affect the growth of our industry. Cosmetics are the product of the society. As society and the needs of its people change, cosmetics also evolve with respect to their contents, packaging, distribution, marketing concepts, and emphasis. In many ways, cosmetics mirror our society, reflecting social changes. Until the early 70's, cosmetics in the US were primarily developed for white women. The civil rights movement of the 60's gave birth to ethnic cosmetics, and products designed for African-Americans became popular in the 70's and 80's. The consumerism of the 70's led the FDA to tighten cosmetic regulations, forcing manufacturers to disclose ingredients on their labels. The result was the spread of safety-oriented, "hypoallergenic" cosmetics and more selective use of ingredients. The new ingredient labeling law in Europe is also likely to affect the manner in which development chemists choose ingredients for new products. Environmental pollution, too, can affect cosmetics trends. For example, the concern over ozone depletion in the stratosphere has promoted the consumption of suncare products. Similarly, the popularity of natural cosmetic ingredients, the search of non-animal testing methods, and ecology-conscious cosmetic packaging seen in recent years all reflect the profound influences of our changing world. In the 1980's, a class of efficacy-oriented skin-care products, which the New York Times dubbed "serious" cosmetics, emerged in the US. "Cosmeceuticals" refer to hybrids of cosmetics and pharmaceuticals which have gained importance in the US in the 90's and are quickly spreading world-wide. In spite of regulatory problems, consumer demand and new technologies continue to encourage their development. New classes of cosmeceuticals are emerging to meet the demands of increasingly affluent Asian consumers as we enter the 21st century. as we enter the 21st century.

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Optimization of Multiclass Support Vector Machine using Genetic Algorithm: Application to the Prediction of Corporate Credit Rating (유전자 알고리즘을 이용한 다분류 SVM의 최적화: 기업신용등급 예측에의 응용)

  • Ahn, Hyunchul
    • Information Systems Review
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    • v.16 no.3
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    • pp.161-177
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    • 2014
  • Corporate credit rating assessment consists of complicated processes in which various factors describing a company are taken into consideration. Such assessment is known to be very expensive since domain experts should be employed to assess the ratings. As a result, the data-driven corporate credit rating prediction using statistical and artificial intelligence (AI) techniques has received considerable attention from researchers and practitioners. In particular, statistical methods such as multiple discriminant analysis (MDA) and multinomial logistic regression analysis (MLOGIT), and AI methods including case-based reasoning (CBR), artificial neural network (ANN), and multiclass support vector machine (MSVM) have been applied to corporate credit rating.2) Among them, MSVM has recently become popular because of its robustness and high prediction accuracy. In this study, we propose a novel optimized MSVM model, and appy it to corporate credit rating prediction in order to enhance the accuracy. Our model, named 'GAMSVM (Genetic Algorithm-optimized Multiclass Support Vector Machine),' is designed to simultaneously optimize the kernel parameters and the feature subset selection. Prior studies like Lorena and de Carvalho (2008), and Chatterjee (2013) show that proper kernel parameters may improve the performance of MSVMs. Also, the results from the studies such as Shieh and Yang (2008) and Chatterjee (2013) imply that appropriate feature selection may lead to higher prediction accuracy. Based on these prior studies, we propose to apply GAMSVM to corporate credit rating prediction. As a tool for optimizing the kernel parameters and the feature subset selection, we suggest genetic algorithm (GA). GA is known as an efficient and effective search method that attempts to simulate the biological evolution phenomenon. By applying genetic operations such as selection, crossover, and mutation, it is designed to gradually improve the search results. Especially, mutation operator prevents GA from falling into the local optima, thus we can find the globally optimal or near-optimal solution using it. GA has popularly been applied to search optimal parameters or feature subset selections of AI techniques including MSVM. With these reasons, we also adopt GA as an optimization tool. To empirically validate the usefulness of GAMSVM, we applied it to a real-world case of credit rating in Korea. Our application is in bond rating, which is the most frequently studied area of credit rating for specific debt issues or other financial obligations. The experimental dataset was collected from a large credit rating company in South Korea. It contained 39 financial ratios of 1,295 companies in the manufacturing industry, and their credit ratings. Using various statistical methods including the one-way ANOVA and the stepwise MDA, we selected 14 financial ratios as the candidate independent variables. The dependent variable, i.e. credit rating, was labeled as four classes: 1(A1); 2(A2); 3(A3); 4(B and C). 80 percent of total data for each class was used for training, and remaining 20 percent was used for validation. And, to overcome small sample size, we applied five-fold cross validation to our dataset. In order to examine the competitiveness of the proposed model, we also experimented several comparative models including MDA, MLOGIT, CBR, ANN and MSVM. In case of MSVM, we adopted One-Against-One (OAO) and DAGSVM (Directed Acyclic Graph SVM) approaches because they are known to be the most accurate approaches among various MSVM approaches. GAMSVM was implemented using LIBSVM-an open-source software, and Evolver 5.5-a commercial software enables GA. Other comparative models were experimented using various statistical and AI packages such as SPSS for Windows, Neuroshell, and Microsoft Excel VBA (Visual Basic for Applications). Experimental results showed that the proposed model-GAMSVM-outperformed all the competitive models. In addition, the model was found to use less independent variables, but to show higher accuracy. In our experiments, five variables such as X7 (total debt), X9 (sales per employee), X13 (years after founded), X15 (accumulated earning to total asset), and X39 (the index related to the cash flows from operating activity) were found to be the most important factors in predicting the corporate credit ratings. However, the values of the finally selected kernel parameters were found to be almost same among the data subsets. To examine whether the predictive performance of GAMSVM was significantly greater than those of other models, we used the McNemar test. As a result, we found that GAMSVM was better than MDA, MLOGIT, CBR, and ANN at the 1% significance level, and better than OAO and DAGSVM at the 5% significance level.