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Environmental and Biological Effects at Narodo, in the Southern Water of Korea, on Bloom of Ichthyotoxic Dinoflagellates Cochlodinium polykrikoides (유해성 Cochlodinium polykrikoides 최초 발생에 관한 나로도 해역의 환경학적 특성 및 식물플랑크톤 군집 구조)

  • Cho Eun Seob
    • Journal of Life Science
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    • v.15 no.2 s.69
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    • pp.225-230
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    • 2005
  • The aim of this study was to examine the fluctuation in phytoplankton assemblages with regarding to environmental conditions and nutrients, which were surveyed quarterly over the fours seasons (February, May, July, and October). In turn, an understanding of biological effects should provide insights into a wide range of initiated Cochlodinium blooms in Narodo. Sampling was carried out throughout 2001 on the coasts of Busan (St. 1), Yeosu (St. 2), Narodo (St. 3), Kohung (St. 4), and Kwangdo (St. 5). The maximum surface water temperature was recorded in July, and it ranged from 20 to $22^{\circ}C$. Salinity showed no great variation, which maintained itself in the range of 29-34 psu. The maximum surface salinity was recorded in February, which was about 34 psu. The chlorophyll $\alpha$ concentration of the surface water ranged from 0.01 to $1.3\;{\mu}g\;1^{-1}$. The concentrations of $NH_{4}-N $ were persistently high from February to October; in particular, the peak was observed at St. 1 in February and May (0.15 and $0.19\;{\mu}mol\;1^{-1}$, respectively), while it was detected at St. 2 in July and October (0.22 and $2.2\;{\mu}mol\;1^{-1}$ respectively). Similar trends to those for $NH_4-N $ were observed in the concentrations of $NO_{2}-N$ and $NO_{3}-N$. In contrast to nitrogen, a distinct peak of $NO_{4}-P$ at St. 3, 4, and 5 was observed throughout year $(0.01-0.1\;{\mu}mol\;1^{-1}$ except for October. At St. 1 encounter a peak of cell number of 30,000 and $13{\times}10^3$ cells $1^{-1}$, respectively, in July and October. During the period of this study, the majority of the taxa were diatoms. The dinoflagellates were rather abundant after February, in particular at St. 3, 4, and 5 which attained an abundance of $10\~20\%$without marked fluctuation during the period of this study. At St. 3, the highest average cell width, $178.11\;{\mu}m$, was recorded: the highest cell length, $337.72\;{\mu}m$, was measured in July. Consequently, dinoflagellates bloom in July at Narodo influenced by warm water current are not only associated with a desirable development of cell morphometric characteristics, but also with the health growth of C. polykrikoides. During the period of this study, warm water currents caused an increased water temperature in Narodo, but did not change the amount of nutrients.

A Quantification Method for the Cold Pool Effect on Nocturnal Temperature in a Closed Catchment (폐쇄집수역의 냉기호 모의를 통한 일 최저기온 분포 추정)

  • Kim, Soo-Ock;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.13 no.4
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    • pp.176-184
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    • 2011
  • Cold air on sloping surfaces flows down to the valley bottom in mountainous terrain at calm and clear nights. Based on the assumption that the cold air flow may be the same as the water flow, current models estimate temperature drop by regarding the cold air accumulation at a given location as the water-like free drainage. At a closed catchment whose outlet is blocked by man-made obstacles such as banks and roads, however, the water-like free drainage assumption is no longer valid because the cold air accumulates from the bottom first. We developed an empirical model to estimate quantitatively the effect of cold pool on nocturnal temperature in a closed catchment. In our model, a closed catchment is treated like a "vessel", and a digital elevation model (DEM) was used to calculate the maximum capacity of the cold pool formed in a closed catchment. We introduce a topographical variable named "shape factor", which is the ratio of the cold air accumulation potential across the whole catchment area to the maximum capacity of the cold pool to describe the relative size of temperature drop at a wider range of catchment shapes. The shape factor is then used to simulate the density profile of cold pool formed in a given catchment based on a hypsometric equation. The cold lake module was incorporated with the existing model (i.e., Chung et al., 2006), generating a new model and predicting distribution of minimum temperature over closed catchments. We applied this model to Akyang valley (i.e., a typical closed catchment of 53 $km^2$ area) in the southern skirt of Mt. Jiri National Park where 12 automated weather stations (AWS) are operational. The performance of the model was evaluated based on the feasibility of delineating the temperature pattern accurately at cold pool forming at night. Overall, the model's ability of simulating the spatial pattern of lower temperature were improved especially at the valley bottom, showing a similar pattern of the estimated temperature with that of thermal images obtained across the valley at dawn (0520 to 0600 local standard time) of 17 May 2011. Error in temperature estimation, calculated with the root mean square error using the 10 low-lying AWSs, was substantially decreased from $1.30^{\circ}C$ with the existing model to $0.71^{\circ}C$ with the new model. These results suggest the feasibility of the new method in predicting the site-specific freeze and frost warning at a closed catchment.

Modelling of Fault Deformation Induced by Fluid Injection using Hydro-Mechanical Coupled 3D Particle Flow Code: DECOVALEX-2019 Task B (수리역학적연계 3차원 입자유동코드를 사용한 유체주입에 의한 단층변형 모델링: DECOVALEX-2019 Task B)

  • Yoon, Jeoung Seok;Zhou, Jian
    • Tunnel and Underground Space
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    • v.30 no.4
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    • pp.320-334
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    • 2020
  • This study presents an application of hydro-mechanical coupled Particle Flow Code 3D (PFC3D) to simulation of fluid injection induced fault slip experiment conducted in Mont Terri Switzerland as a part of a task in an international research project DECOVALEX-2019. We also aimed as identifying the current limitations of the modelling method and issues for further development. A fluid flow algorithm was developed and implemented in a 3D pore-pipe network model in a 3D bonded particle assembly using PFC3D v5, and was applied to Mont Terri Step 2 minor fault activation experiment. The simulated results showed that the injected fluid migrates through the permeable fault zone and induces fault deformation, demonstrating a full hydro-mechanical coupled behavior. The simulated results were, however, partially matching with the field measurement. The simulated pressure build-up at the monitoring location showed linear and progressive increase, whereas the field measurement showed an abrupt increase associated with the fault slip We conclude that such difference between the modelling and the field test is due to the structure of the fault in the model which was represented as a combination of damage zone and core fractures. The modelled fault is likely larger in size than the real fault in Mont Terri site. Therefore, the modelled fault allows several path ways of fluid flow from the injection location to the pressure monitoring location, leading to smooth pressure build-up at the monitoring location while the injection pressure increases, and an early start of pressure decay even before the injection pressure reaches the maximum. We also conclude that the clay filling in the real fault could have acted as a fluid barrier which may have resulted in formation of fluid over-pressurization locally in the fault. Unlike the pressure result, the simulated fault deformations were matching with the field measurements. A better way of modelling a heterogeneous clay-filled fault structure with a narrow zone should be studied further to improve the applicability of the modelling method to fluid injection induced fault activation.

Flowering Patterns of Miscanthus Germplasms in Korea (국내 수집 억새 유전자원의 출수 특성)

  • An, Gi-Hong;Um, Kyoung-Ran;Lee, Jun-Hee;Jang, Yun-Hui;Lee, Ji-Eun;Yu, Gyeong-Dan;Cha, Young-Lok;Moon, Yun-Ho;Ahn, Jong-Woong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.60 no.4
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    • pp.510-517
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    • 2015
  • Miscanthus has been considered as the most promising bioenergy crop for lignocellulosic biomass production. In Korea, M. sacchariflorus and M. sinensis can be found easily in all regions. It is a great advantage to utilize as important species with respect to genetic and cross-breeding programs materials for creation of novel hybrids. For successful breeding programs, it is important to precisely understand the variability of flowering traits among Miscanthus species as breeding parents materials. In this study, flowering traits were observed daily in 960 germplasms of two Miscanthus species (M. sacchariflorus and M. sinensis) for growing seasons over 2 years. The flowering process was divided into three stages. ST (sprouting time) was recorded when first leaf of the plant emerged on soil. FS1 (flowering stage 1) and FS2 (flowering stage 2) were recorded when flag leaf was firstly observed, and 1 cm of panicle was showing on at least one stem, respectively. For 2013 and 2014, the latest germplasms exerted flag leaf, i.e. September 30 (DOY of FS1 164.1) and September 4 (DOY of FS1 141.0) occurred M. sacchariflorus cv. Geodae 1 and M. sacchariflorus cv. Uram collected from Southern Korea (Jeollanam-do), while Miscanthus germplasms collected from northern Korea (Gyeonggi-do) which emerged the earliest flag leaf in July and August, significantly decreased DOY. For DOY from ST to FS2, M. sacchriflorus germplasms ranged from 140 to 190 days, and 110 to 170 days for 2013 and 2014. The highest frequency showed to 160 days for 2013, and 150 days for 2014. In M. sinensis germplasms, the highest frequency showed to 180 days for 2013, and 170 days for 2014. In the results of correlation between the day of years from ST to FS2 for 2013 and 2014, M. sacchriflorus and M. sinensis showed high coefficient of correlation (0.70 and 0.89). It can be supposed that flowering characteristics of Miscanthus are largely affected by the unique phenotypic characteristic of native habitat than environmental factors of the current planted site. This study for flowering traits of Miscanthus may provides an important information in order to expedite the introduction as breeding materials for creation of new hybrid.

Origin of Layering and Its Relation to Magma Convection in the Skaergaard Intrusion (Skaergaard 암체에서 layering의 기원과 그의 마그마 대류와의 관계)

  • Yun D. Jang
    • Economic and Environmental Geology
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    • v.34 no.6
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    • pp.627-648
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    • 2001
  • At least two distinct types of layering are present in the middle zone of the Skaergaard intrusion; alternating plagioclase-rich and pyroxene-rich, macro-rhythmic layers, and smaller scale, modally-graded, rhythmic layers. The macro-rhythmic layers are ubiquitous in the middle zone of the Layered Series, but are not observed in the lower and upper zone of the Layered Series or in the wall or roof tories of the intrusion. They range from 0.3 to 17.3 m in thickness, have sharp upper and lower boundaries, and can be traced laterally for over 2 ]fm in outcrop. Although individual macrorhythmic layers are not internally graded, many contain smaller-scale, modally-graded layers. Modally-graded. rhythmic layers are a common feature of the Layered Series but are not abundant in either the Upper Border Series or the Marginal Border Series. They range in thickness from 1 to 50 cm and can be traced laterally in outcrop for up to 100 m. Their lateral termination ranges from abrupt to gradational, and they are often associated with cut and fill structures and crossbedding suggestive of current activity. They are characterized by sharp lower and gradational upper contacts, and by strong intra-layer modal grading with olivine, ilmenite, and magnetite concentrated at the base, pyroxene concentrated above the base, and plagioclase concentrated at the top. The layers are also grain-size graded with the maximum size for each phase occurring at the horizon in the layer where the phase is most abundant. Modally-graded, rhythmic layers in the middle zone of the Layered Series occur within both plagioclase-rich and pyroxene-rich macro-rhythmic layers.

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Evaluation of Disaster Resilience Scorecard for the UN International Safety City Certification of Incheon Metropolitan City (인천시 UN 국제안전도시 인증을 위한 재난 복원력 스코어카드 평가)

  • Kim, Yong-Moon;Lee, Tae-Shik
    • Journal of Korean Society of Disaster and Security
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    • v.13 no.1
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    • pp.59-75
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    • 2020
  • This study is a case study that applied 'UNDRR's Urban Disaster Resilience Scorecard', an evaluation tool necessary for Incheon Metropolitan City to be certified as an international safe city. I would like to present an example that the results derived from this scorecard contributed to the Incheon Metropolitan City Disaster Reduction Plan. Of course, the Disaster Resilience Scorecard can't provide a way to improve the resilience of every disaster facing the city. However, it is to find the weakness of the resilience that the city faces, and to propose a solution to reduce the city's disaster risk. This is to help practitioners to recognize the disaster risks that Incheon Metropolitan City faces. In addition, the solution recommended by UNDRR was suggested to provide resilience in areas vulnerable to disasters. It was confirmed that this process can contribute to improving the disaster resilience of Incheon Metropolitan City. UNDRR has been spreading 'Climate Change, Disaster-resistant City Creation Campaign', aka MCR (Making Cities Resilient) Campaign, to cities all over the world since 2010 to reduce global cities' disasters. By applying the disaster relief guidelines adopted by UNDRR, governments, local governments, and neighboring cities are encouraged to collaborate. As a result of this study, Incheon Metropolitan city's UN Urban Resilience Scorecard was evaluated as a strong resilience field by obtaining scores of 4 or more (4.3~5.0) in 5 of 10 essentials; 1. Prepare organization for disaster resilience and prepare for implementation, 4. Strong resilience Urban development and design pursuit, 5. Preservation of natural cushions to enhance the protection provided by natural ecosystems, 9. Ensure effective disaster preparedness and response, 10. Rapid restoration and better reconstruction. On the other hand, in the other five fields, scores of less than 4 (3.20~3.85) were obtained and evaluated as weak resilience field; 2. Analyze, understand and utilize current and future risk scenarios, 3. Strengthen financial capacity for resilience, 6. Strengthen institutional capacity for resilience, 7. Understanding and strengthening social competence for resilience, 8. Strengthen resilience of infrastructure. In addition, through this study, the risk factors faced by Incheon Metropolitan City could be identified by priority, resilience improvement measures to minimize disaster risks, urban safety-based urban development plans, available disaster reduction resources, and integrated disasters. Measures were prepared.

Geographical Distribution of Diving Beetles (Dytiscidae) in Korean Paddy Ecosystem (우리나라 논 서식 물방개과의 지리적 분포)

  • Han, Min-Su;Kim, Myung-Hyun;Bang, Hea-Son;Na, Young-Eun;Lee, Deog-Bae;Kang, Kee-Kyung
    • Korean Journal of Environmental Agriculture
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    • v.30 no.2
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    • pp.209-215
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    • 2011
  • BACKGROUND: The paddy ecosystem is periodically disturbed with a relatively consistent cycle in short term. However, in long term aspect, the paddy as habitats of organisms has been affected by the change in farming practices. Accordingly, the composition and their densities of fauna species inhabiting the wet paddy has been changed. The geological distribution of a species is very helpful to understand the past and current status of habitats and biodiversity. METHODS AND RESULTS: We monitored 290 sites of open plain paddy or terraced valley paddy located in 138 cities or counties of South Korea and analyzed examine geological distribution of a taxon of freshwater invertebrates, diving beetles (Dytiscidae) which inhabited the paddy ecosystem. This survey was conducted from 2005 through 2007. The total species of diving beetles found in the paddy were identified to be 15 genus 26 species among the family of Dytiscidae. Among them, 24 species were found in the terraced valleys-in paddy fields, and 19 species were found in the open plain paddy fields. Eleven species of them were rarely found in the paddy. The average body size of the adult diving beetles of each species was between 2.0 and 35.0 mm. Most of the diving beetle species except for 11 species with rare frequency of occurrence were found in almost all sites of the terraced valley paddy fields but three species (Agabus browni, Agabus japnicus, and Ilybius apicalis) were not found in the open plain paddy fields. The species distributed relatively widely over some sites of the open plain paddy fields were Guignotus japonicus, and Rhantus pulverosus. Specifically, Ilybius apicalis was found in a specific region, the east-southern part of Korean peninsula, whereas Coelambus chinensis was found only in valley paddy field of the region where Ilybius apicalis was not found. Overall distribution range of diving beetles in open plain paddy fields was limited to few area than in terraced valley paddy fields. CONCLUSION(s): The differences in the range of distribution of diving beetles between terraced valley paddy fields and open plain paddy fields was thought to be the result of an complex action of physico-chemical environments such as annual water status and the degree of chemical application involving differences in the extent of disturbance of the paddy ecosystem, the connectivity of the paddy to an adjacent biotope, and interrelationships among competitors.

Research Direction for Functional Foods Safety (건강기능식품 안전관리 연구방향)

  • Jung, Ki-Hwa
    • Journal of Food Hygiene and Safety
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    • v.25 no.4
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    • pp.410-417
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    • 2010
  • Various functional foods, marketing health and functional effects, have been distributed in the market. These products, being in forms of foods, tablets, and capsules, are likely to be mistaken as drugs. In addition, non-experts may sell these as foods, or use these for therapy. Efforts for creating health food regulations or building regulatory system for improving the current status of functional foods have been made, but these have not been communicated to consumers yet. As a result, problems of circulating functional foods for therapy or adding illegal medical to such products have persisted, which has become worse by internet media. The cause of this problem can be categorized into (1) product itself and (2) its use, but in either case, one possible cause is lack of communications with consumers. Potential problems that can be caused by functional foods include illegal substances, hazardous substances, allergic reactions, considerations when administered to patients, drug interactions, ingredients with purity or concentrations too low to be detected, products with metabolic activations, health risks from over- or under-dose of vitamin and minerals, and products with alkaloids. (Journal of Health Science, 56, Supplement (2010)). The reason why side effects related to functional foods have been increasing is that under-qualified functional food companies are exaggerating the functionality for marketing purposes. KFDA has been informing consumers, through its web pages, to address the above mentioned issues related to functional foods, but there still is room for improvement, to promote proper use of functional foods and avoid drug interactions. Specifically, to address these issues, institutionalizing to collect information on approved products and their side effects, settling reevaluation systems, and standardizing preclinical tests and clinical tests are becoming urgent. Also to provide crucial information, unified database systems, seamlessly aggregating heterogeneous data in different domains, with user interfaces enabling effective one-stop search, are crucial.

Microbial Contamination Levels in the Raw Materials of Home Meal Replacement Shabu-Shabu Meal Kit Distributed in Markets (가정간편식(Home Meal Replacement, HMR) 샤브샤브 밀키트의 원료별 미생물 오염도 분석)

  • Jeon, Eun Bi;Kim, Ji Yoon;Choi, Man-Seok;Choi, Seungho;Bang, Hyeon-Jo;Park, Shin Young
    • Journal of Food Hygiene and Safety
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    • v.35 no.4
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    • pp.375-381
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    • 2020
  • This study assessed the contamination levels of total aerobic bacteria, fungi, coliforms, Escherichia coli, Bacillus cereus, and Staphylococcus aureus and qualitative analysis of Salmonella spp. and Listeria monocytogens in six raw materials (beef, bean sprout, Chinese cabbage, king oyster mushroom, Korean cabbage, and sweet pumpkin) of home meal replacement (HMR) Shabu-Shabu meal kit distributed in markets. The total aerobic bacteria, fungi, and coliforms were detected as 3.98-6.50, 2.78-3.52, and 2.02-3.28 log CFU/g, respectively. Especially, beef was highly contaminated with total aerobic bacteria (6.50 log CFU/g) and coliforms (3.28 log CFU/g). Over 5 log CFU/g of total aerobic bacteria were also detected in bean sprout, Chinese cabbage, and sweet pumpkin. Less than < 2 log CFU/g of coliforms were detected in all vegetables. E. coli was not detected in any of the six samples (ND: < 1 log CFU/g). S. aureus was detected as 1.33-1.71 log CFU/g in most samples but it was not detected in beef and Korean cabbage. B. cereus was assessed as 1.15-2.01 log CFU/g in most samples but it was not detected in Korean cabbage. L. monocytogenes was qualitatively detected as 25-50% in most samples except for king oyster mushroom. Salmonella spp. were not qualitatively detected in any of the six samples. The microbial contamination levels determined in the current study may be potentially used as the basic data to execute microbial risk assessments of HMR foods such as Shabu-Shabu meal kit.

A Study on the Successful Case of Brand Renewal through American National Brand 'C' Company's Marketing Strategy (미국(美國) 내셔널브랜드 C사(社)의 마케팅전략(戰略)을 통한 브랜드리뉴얼 성공사례(成功事例) 연구(硏究))

  • Koh, Hee-Sook
    • Journal of Fashion Business
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    • v.6 no.1
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    • pp.137-154
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    • 2002
  • It's not easy to renew old brand of over 50 years history to the tastes of new consumer of our time. Most of national brands that has a history of some 20 years in Korea have strove for continuation and growth of brand to no avails, which can be taken as a good example of current situation. For instance, C company, one of the National brand of US which has a history of 51 years, has made its position secure as a fashion group and based itself on a sound foundation by establishing new marketing strategy and completing successful brand renewal in the process of strategic M&A with Italian company. Those successful marketing strategies are as follows. 1) they regarded both market and consumer oriented marketing activity as company's highest priority strategy and put great emphasis upon concentration on target market and reestablishment of brand image of business casual wear. 2) Setting up and operating planning team composed of merchandizer alone in Milano, they set the direction of plan on the basis of concentrated research on potential item in market according to thorough market research done by buying office in Korea, branch office in Hong Kong and buyer in US prior to blueprint planning for season. 3) Great emphasis was placed on business which focused on intensive presentation of basic key item for apparel career women who are main consumer group in the midium-low prices market in US and on supplementation of size and color. they named this line 'collectibles' and helped their customer develop their own clothes plan without worrying about the change of color and fabric by supporting same fabric and color throughout the year and enabled them to add variation easily by supplementing new trend item. 4) Company set black as a main color that lots of apparel career women find easy to care and to express their own image and presented them with pebble which belongs to navy and beige and added fashion color such as wine and brown etc as season goes by. They constructed basic line in order for their customers to coordinate purchased item with new one or to add them to present collection, and to achieve efficient sale by setting up strategy which allows this cross coordination and changing pattern occasionally. 5) Though basic jacket for 99$, short slim skirt for 49$ are products within midium-low prices range, in the material planning stage aiming at production of item that has both resonable function appealing to consumer and is fashionable, synthetic material had to be used as a main source due to price competitiveness. Despite this situation, considering comfortable sense of fit and refined drape of silhouette that has no sign of cheap material, whole collectible line was divided into two items, which contributed to reduction of cost. In case of material that is composed of triacetate and polyester in 70 to 30 ratio, was used up to 4 million yard, which allowed drastic curtailment of cost accompanied by concentration. In case of 'collectibles' line, using Korean material mainly, C company chose to have their product sewed in Southeast Asian countries where transportation is well developed and both productivity and quality verified by operating global production system which aiming at cutdown of cost through outsourcing production from the country where labor cost is low and getting finished product. Polarization between present consumers telling us that consumers with the mind of middle classes in the past no longer exists between consumers who seek after only fine article of highest quality and wise consumers who are sensible enough to judge bubble on correlation between price and quality. To cope with this change in new consumer mind, apparel makes changing their policy so as to produce item that has reasonable quality and falls within affordable price range anywhere in the world. and they're striving to get out of difficult situation by operating global marketing strategy which stresses separation of planning, production and sale and sensibility of fashion shared worldwide. The marketing strategy of C company can be exemplified as a successful one.