• Title/Summary/Keyword: Initial growth

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Shape Optimization in Laminated Composite Plates by Volume Control (최적 제어를 통한 복합적층판의 형상최적화)

  • 한석영;백춘호;박재용
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2003.10a
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    • pp.277-282
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    • 2003
  • The growth-strain method was applied to cutout optimization in laminated composite plates. Since the growth-strain method optimizes a shape by generating the bulk strain to make the distributed parameter uniform, the distributed parameter was chosen as Tsai-Hill value. In this study, of particular interest is to see whether the growth-strain method developed for shape optimization in isotropic media would work for laminated composite Plates. In volume control of the growth-strain method, it makes Tsai-Hill value at each element uniform in laminated composite plates under the predetermined volume. The shapes optimized by Tsai-Hill fracture index were compared with those of the initial shapes for the various load conditions and predetermined volumes of laminated composite plates. As a result, it was verified that volume control of the growth-strain method worked very well for cutout optimization in laminated composite plates.

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Growth of Nanosized Pyrolytic Carbon Whisker by Catalytic Pyrolysis of Methane (저온에서 methane의 촉매적 열분해시 nanosized pyrolytic carbon whisker성장의 발견)

  • H. S. Rhee;Park, Y. T.
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2003.04a
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    • pp.173-175
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    • 2003
  • At the low temperature of $950^{\circ}C$ the $\mu\textrm{m}$-sized whisker growth during the catalytic CVD of pyrolytic carbon from methane with $H_2$- and Ar-gas on quartz substrate with NiO powder was found in this work. In the preliminary study it was observed from pure methane pyrolysis without catalyst at the high temperature $1500~1700^{\circ}C$. If the growth whisker should be stopped at initial stage, about 20 min. of the methane pyrolysis, it would be nanosized whisker growth. The screw growth mechanism and unique mechanical properties of whisker for composites were also recognized. If the pyrolysis would be continued, we could found also spiral growth of whistlers with diameter of about 1, 5 mm. The large length of whisker was about 10 cm in 20 minute.

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An Exploratory Study of business support policy by growth phases for Small and medium sized enterprises -Focused on Cheonan and Asan in ChungNam- (중소기업의 성장단계별 지원정책에 관한 탐색적 연구 -충청남도 천안·아산지역을 중심으로-)

  • Lee, Jae-Beom
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.5
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    • pp.2215-2224
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    • 2013
  • This study performed empirical analysis to estimate SMEs needs in terms of business support policy by growth stages(start-up growth expansion). The subject is the SMEs in Cheonan and Asan, ChungNam and the results are as follows. First, In the initial start-up stage, management plays a key role in dealing with money, labor force, markets and technology while running the organization is a key role of the management in the expansion stage. Major policies to help SMEs grow includes money provision needed in the start-up stage, domestic marketing assistance and the provision of human resources in the growth stage, and assistance in foreign marketing and R&D in the expansion stage. Second, To achieve markets businesses aim at entering the existing and niche markets in the initial phase, and creating new markets in the growth phase. Third, Labor force for technology, sales and management planning in the start-up stage, marketing in the growth stage, and labor force for production in the expansion stage are core man- power needed. Fourth, Money for technology development, securing land for factories, organizing man power, securing markets and running the company is needed in the initial and growth stages while fund for facility investment is needed to grow in the expansion stage. Five, Regarding technology, the initial stage needs technology related to new product development, renewing existing products, improving the existing manufacturing process or developing new manufacturing process, while the growth stage needs processing techniques, and the expansion stage needs technology for developing new manufacturing process. Sixth, Making supply contracts with conglomerates, SMEs and public institutions, and sales to foreign markets are ways for SMEs to grow sales. Seventh, What SMEs wish to get includes business incubating support, R&D assistance, information exchanges, practical use of the R&D results, merchandising support, help with the land to build factories and custom-made support for management in the foundation stage while the support they want to get in the growth stage and in the expansion stage is training assistance and trial production respectively.

A Quality and Pricing Strategy for Web Sites Providing Initial Free Services (초기 무료 서비스를 제공하는 웹사이트의 품질 및 가격전략)

  • Lee Kang-Bae
    • Management & Information Systems Review
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    • v.9
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    • pp.65-80
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    • 2002
  • As the growth of Internet business, many web sites have been developed their own Internet business strategies. Yet, many web sites have difficulties to make profit. In this paper, an economic model is developed to analyze web sites' quality and pricing strategies when they initiate their services as free services and develop advertising services and other charged services. By analyzing the economic model, optimal quality and prices was found. And by analyzing the optimal strategy, I found that web sites should properly decide their market share on initial customer. Finally, the importance of web sites' productivity to make profit is emphasized.

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UNIQUENESS OF SOLUTIONS FOR A DEGENERATE PARABOLIC EQUATION WITH ABSORPTION

  • Lee, Jin Ho;Jang, Seong Hee
    • Korean Journal of Mathematics
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    • v.5 no.2
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    • pp.151-167
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    • 1997
  • We estimate the interior Lipschitz norm and maximum of the solution for degenerate parabolic equations with absorption. Also obtain the growth rate of the solution $u$ in terms of time $t$. From this we show the uniqueness of solution with respect to the initial trace.

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Fermentative and Sensory Characteristics of Kimchi added Mustard Root (Brassica juncea) (갓무를 첨가한 김치의 발효 및 관능 특성)

  • Hwang, Jong-Hyun
    • The Korean Journal of Food And Nutrition
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    • v.28 no.5
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    • pp.926-932
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    • 2015
  • This study was conducted to examine the effect of mustard root on the shelf life of kimchi. Ethanol extract was prepared from the mustard root (Brassica juncea) and antimicrobial activities were examined against Lactobacillus plantarum and Leuconostoc mesenteroides which are the representative lactic bacteria in kimchi. Growth of lactic bacteria were inhibited by ethanol extract from mustard root and the growth time of Leuconostoc mesenteroides was delayed more than 24 hours compared with that of Lactobacillus plantarum. Also, the fermentative and sensory characteristics of kimchi with mustard root were evaluated during fermentation at $10^{\circ}C$. The pH and acidity was lower than that of the control kimchi and the fermentation period was retarded in proportion to the increase in mustard content. The total numbers of microorganism and lactic bacteria in the control kimchi were higher than those in kimchi with mustard root during fermentation. Leuconostoc sp. in the initial stage of growth was more inhibited than Lactobacillus sp. While the pH of kimchi were in the initial stage, the sensory evaluation score for savory flavors of the kimchi with mustard root was lower than that of control due to bitterness and pungency. But when the pH of kimchi reached the optimum stage, the scores for texture and savory flavor of kimchi with mustard root were higher than that of the control. Then overall quality score for kimchi with mustard root increased as bitterness decreased.

Fusarium moniliforme NRRL 13569의 액체 배양 중의 성장과 Fumonisin B$_1$ 생성

  • Kim, Eun-Kyung;Chung, Soo-Hyun;Lee, Sung-Taik;Kim, Young-Bae
    • Microbiology and Biotechnology Letters
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    • v.25 no.5
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    • pp.501-505
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    • 1997
  • The effects of some nutrients and culture conditions on the growth and the production of fumonisin B$_{1}$, (FB$_{1}$) from Fusarium moniliforme NRRL 13569 were investigated in liquid culture. Xylose and soytone yielded the highest mycelial growth as the C- and N-source, respectively. The highest level of FB$_{1}$, was obtained when yeast extract was used as the N-source but no FB$_{1}$, from NaNO$_{3}$. While Fe$^{+++}$ showed inhibition effect on FB$_{1}$, production, Zn$^{++}$ enhanced the FB$_{1}$, production as well as the mycelial growth. FB$_{1}$, was maximally produced when the initial pH value and the specific surface area of the medium was adjusted to 5 and 1.4 cm$^{2}$/ml, respectively. FB$_{1}$ formation reached the maximum value (210, 000 ng/ml) in 30 days and then decreased in Czapek medium substitued with 1% xylose and 0.3% yeast extract, and supplemented with 0.2% NH$_{4}$H$_{2}$PO$_{4}$ where the initial pH value and the specific surface area of the medium are optimally controlled.

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