• 제목/요약/키워드: Technical Stability

검색결과 665건 처리시간 0.03초

성형안정성을 고려한 바이오칩용 측벽 이동형 금형설계 및 제작 (Design and fabrication of molds moved wall thickness for biochip considering molding stability)

  • 고영배;김종선;민인기;유재원;김종덕;윤경환;이성호;김경민;김병일;황철진
    • Design & Manufacturing
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    • 제2권2호
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    • pp.25-28
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    • 2008
  • Micro fabrication of biochip such like lab-on-a-chip becomes increasingly important. In this study, we designed and manufactured of new molds which were main factors for forming process in order to mass produce of biochip using forming process. Forming analysis of biochip was performed by Moldflow software. Results of this study are able to design and manufacture the mold which can be easy to eject the workpiece by using the slide mechanism for biochip.

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수산기업의 부실화 요인 및 예측에 관한 연구 (A Study on the Distress Prediction in the Fishery Industry)

  • 이윤원;장창익;홍재범
    • 한국수산경영학회:학술대회논문집
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    • 한국수산경영학회 2007년도 추계학술발표회 및 심포지엄
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    • pp.167-184
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    • 2007
  • The objectives of this paper are to identify the causes of the corporate distress and to develop a distress prediction model with the financial information in fishery industry. In this study, the corporate distress is defined as economic failure and technical insolvency. Economic failure occurs by reduction, shut-down, or change of the business and technical insolvency results from failure to pay the financial debt of companies. The 33 distressed firms from 1991 to 2003 were composed by 14 economic failure companies, 15 technical insolvency companies. 4 companies applied to the both cases. The analysis of distress prediction of fishery companies were accomplished according to the distress definition. The analysis was carried out as two steps. The first step was the univariate analysis, which was used for checking the prediction power of individual financial variable. The t-test is used to identify the differences in financial variables between the distressed group and the non-distressed group. The second step was to develop distress prediction model with logistic regression. The variables showed the significant difference in univariate analysis were selected as the prediction variables. The financial ratios, used in the logistic regression model, were selected by backward elimination method. To test stability of the distress prediction model, the whole sample was divided as three sub-samples, period 1(1990$\sim$1993), period 2(1994$\sim$1997), period 3(1998$\sim$2002). The final model built from whole sample appled each three sub-samples. The results of the logistic analysis were as follows. the growth, profitability, stability ratios showed the significant effect on the distress. the some different result was found in the sub-sample (economic failure and technical insolvency). The growth and the profitability were important to predict the economic failure. The profitability and the activity were important to predict technical insolvency. It means that profitability is the really important factor to the fishery companies.

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수산기업의 부실화 요인과 그 예측에 관한 연구 (A Study on the Distress Prediction in the Fishery Industry)

  • 장창익;이윤원;홍재범
    • 수산경영론집
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    • 제39권2호
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    • pp.61-79
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    • 2008
  • The objectives of this paper are to identify the causes of the corporate distress and to develop a distress prediction model with the financial information in fishery industry. In this study, the corporate distress is defined as economic failure and technical insolvency. Economic failure occurs by reduction, shut - down, or change of the business and technical insolvency results from failure to pay the financial debt of companies. The 33 distressed firms from 1991 to 2003 were composed by 14 economic failure companies, 15 technical insolvency companies. 4 companies applied to the both cases. The analysis of distress prediction of fishery companies were accomplished according to the distress definition. The analysis was carried out as two steps. The first step was the univariate analysis, which was used for checking the prediction power of individual financial variable. The t - test is used to identify the differences in financial variables between the distressed group and the non - distressed group. The second step was to develop distress prediction model with logistic regression. The variables showed the significant difference in univariate analysis were selected as the prediction variables. The financial ratios, used in the logistic regression model, were selected by backward elimination method. To test stability of the distress prediction model, the whole sample was divided as three sub-samples, period 1(1990 - 1993), period 2(1994 - 1997), period 3(1998 - 2002). The final model built from whole sample appled each three sub - samples. The results of the logistic analysis were as follows. the growth, profitability, stability ratios showed the significant effect on the distress. the some different result was found in the sub - sample (economic failure and technical insolvency). The growth and the profitability were important to predict the economic failure. The profitability and the activity were important to predict technical insolvency. It means that profitability is the really important factor to the fishery companies.

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STABILITY OF THE JENSEN TYPE FUNCTIONAL EQUATION IN BANACH ALGEBRAS: A FIXED POINT APPROACH

  • Park, Choonkil;Park, Won Gil;Lee, Jung Rye;Rassias, Themistocles M.
    • Korean Journal of Mathematics
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    • 제19권2호
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    • pp.149-161
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    • 2011
  • Using fixed point methods, we prove the generalized Hyers-Ulam stability of homomorphisms in Banach algebras and of derivations on Banach algebras for the following Jensen type functional equation: $$f({\frac{x+y}{2}})+f({\frac{x-y}{2}})=f(x)$$.

Influence of aspect ratio and fibre orientation on the stability of simply supported orthotropic skew plates

  • Kutlu, Darilmaz
    • Steel and Composite Structures
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    • 제11권5호
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    • pp.359-374
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    • 2011
  • In this paper, the influence of fibre orientation and aspect ratio on stability analysis of simply supported skew plates subjected to in plane loading is studied by using a four noded hybrid plate finite element. The formulation of the element is based on Hellinger-Reissner variational principle. The element is developed by combining a hybrid plane stress element and a hybrid plate element. Some numerical problems are solved and the effects of skew angle, aspect ratio, fibre orientation and loading type on the critical buckling loads are highlighted.

GENERALIZED HYERS-ULAM-RASSIAS STABILITY FOR A GENERAL ADDITIVE FUNCTIONAL EQUATION IN QUASI-β-NORMED SPACES

  • Moradlou, Fridoun;Rassias, Themistocles M.
    • 대한수학회보
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    • 제50권6호
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    • pp.2061-2070
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    • 2013
  • In this paper, we investigate the generalized HyersUlam-Rassias stability of the following additive functional equation $$2\sum_{j=1}^{n}f(\frac{x_j}{2}+\sum_{i=1,i{\neq}j}^{n}\;x_i)+\sum_{j=1}^{n}f(x_j)=2nf(\sum_{j=1}^{n}x_j)$$, in quasi-${\beta}$-normed spaces.

계면활성제 첨가가 커튼 코팅용 도공액의 물성과 커튼 안정성에 미치는 영향 (Effect of surfactant addition on curtain coating color properties and curtain stability)

  • 오규덕;김채훈;윤혜정;이학래
    • 펄프종이기술
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    • 제43권5호
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    • pp.49-54
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    • 2011
  • Curtain coating has been considered as the best coating technology because it is a coating technology that forms contour coating layer with better coverage. To increase the curtain stability surfactants are being used. In this study, the effect of a surfactant on the stability of curtain coating colors was examined by evaluating dynamic surface tension with a bubble surface tensiometer. Di-2-ethylhexyl sodium sulfosuccinate was used as a surfactant since it showed low dynamic surface tension at low surface age. And we evaluated the influence of surfactant on coating color properties including surface tension, viscosity and curtain stability. The surface tension of coating color was decreased when surfactant addition was increased up to 0.5 pph, but it was leveled off at 0.3 pph of surfactant addition. With the increase of surfactant addition rate, viscosity of coating color were increased. Micelles formed by surfactant contributed to the increase of the viscosity. Curtain stability was improved with the addition of surfactant until it reached up to 0.5 pph. Excessive addition of surfactant (> 0.5 pph) didn't improve curtain stability. This was attributed to Marangoni effect(self-healing) and decreasing of curtain thickness.

고기능성 생활용기 성형을 위한 대용량 스택금형 개발 (Development of large-capacity stack mold for the high-performance household case)

  • 신장순;김유진;정귀재;황순환;허영무;윤길상;정우철;서태일
    • Design & Manufacturing
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    • 제2권3호
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    • pp.28-31
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    • 2008
  • In recent, the demand of high-productivity injection mold is increased because of the growth of international packaging market which is induced by an increase of population. The increase of productivity leads to the large-capacity injection molding machine and peripheral devices. For solving this problem, the stack mold which is based on the exsiting machine and device has researched in advanced countries actively. In this paper, as the preliminary research of stack mold development, the stack mold which has 2 level ${\times}4$ cavity was designed and fabricated. Besides, the motion and structural analysis were performed to verify the stability of developed stack mold.

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상향으로 설치된 쏘일네일링의 안정성 및 거동에 관한 연구 (A Study on the Stability and Behavior of upward Soil-nailing)

  • 김재윤;이인;최근혁;김홍택
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.1086-1091
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    • 2009
  • The purpose of this study is to provide the technical information of the stability change and behaviour characteristics in case upward direction of soil nailing is installed. Generally, the soil nailing which installed in case of vertical excavation or for the purpose of the slope stability is installed between 5 to 15 degree of downward direction. The downward direction of the soil nailing method has lots of advantages such as the increase of the stability, the convenience of the grout compared to upward direction of soil nailing. Even though the upward direction of the soil nailing has the disadvantages in terms of the stability and the grout construction, horizontal displacement tends to be decreased.

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THE EFFECTS OF TiN PARTICLES ON THE HAZ MICROSTRUCTURE AND TOUGHNESS IN HIGH NITROGEN TiN STEEL

  • Jeong, Hong-Chul;An, Young-Ho;Choo, Wung-Yong
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.217-221
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    • 2002
  • In the coarse grain HAZ adjacent to the fusion line, most of the TiN particles in conventional Ti added steel are dissolved and austenite grain growth is easily occupied during welding process. To avoid this difficulty, thermal stability of TiN particle is improved by increasing the nitrogen content in steel. In this study, the effect of high nitrogen TiN particle on preventing austenite grain growth in HAZ was investigated. Increased thermal stability of TiN particle is helpful for preventing the austenite grain growth by pinning effect. High nitrogen TiN particle in simulated HAZ were not dissolved even at high temperature such as 1400 C and prevented the austenite grain growth in simulated HAZ. Owing to small austenite grain size in HAZ the width of coarse grain HAZ in high nitrogen TiN steel was decreased to 1/10 of conventional TiN steel. Even high heat input welding, the microstructure of coarse grain HAZ consisted of fine polygonal ferrite and pearlite and toughness of coarse grain HAZ was significantly improved.

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