• 제목/요약/키워드: almost stability

검색결과 554건 처리시간 0.025초

HOMOMORPHISMS BETWEEN C*-ALGEBRAS ASSOCIATED WITH THE TRIF FUNCTIONAL EQUATION AND LINEAR DERIVATIONS ON C*-ALGEBRAS

  • Park, Chun-Gil;Hou, Jin-Chuan
    • 대한수학회지
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    • 제41권3호
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    • pp.461-477
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    • 2004
  • It is shown that every almost linear mapping h : A\longrightarrowB of a unital $C^{*}$ -algebra A to a unital $C^{*}$ -algebra B is a homomorphism under some condition on multiplication, and that every almost linear continuous mapping h : A\longrightarrowB of a unital $C^{*}$ -algebra A of real rank zero to a unital $C^{*}$ -algebra B is a homomorphism under some condition on multiplication. Furthermore, we are going to prove the generalized Hyers-Ulam-Rassias stability of *-homomorphisms between unital $C^{*}$ -algebras, and of C-linear *-derivations on unital $C^{*}$ -algebras./ -algebras.

신규 Carbapenem 유도체 CRB 529, 535, 538, 545, 550의 시험관내 항균력 평가 (In Vitro Antibacterial Activities of CRB 529, 535, 538, 545 and 550, A New Carbapenem Derivatives)

  • 민관기;김준겸;이홍우;김정우
    • 약학회지
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    • 제39권3호
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    • pp.215-222
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    • 1995
  • The in vitro antibacterial activities of new carbapenem. CRB 529, 535, 538, 545 and 550 with meropenem and imipenem were compared. CRB 529. 535, 538, 545 and 550 proved to have a broad an tibacterial spectrum. Its in vitro activity against standard 20 strains was almost the same as that of imipenem and slightly higher than that of meropenem. However. against clinical isolated P. aeruginosa, CRB 529, 535, 538, 545 and 550 showed significantly higher activity than imipenem, and also CRB 529, 535, 538, 545 and 550 showed almost the same activity than imipenem and meropenem against 82 clinical isolated strains including S. aureus (MRSA), S. aureus (MSSA), E. faecalis, E. facium, E. coli, P. aeruginosa, K. pneumonia, P. mirabiris, P. stuartii, M. morganii, C. freundii, E. cloacae, S. marcescens and A. calcoaceticus var. anitratus. The stability of CRB 529, 535, 538, 545 and 550 against porcine renal dehydropeptidase-I(DHP-1) was 10 folds higher than that of imipenem and was 3 folds higher than that of meropenem.

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해저탐사잠수정의 연직평면에서의 방향안정성에 관한 연구 (A Study about the Pitch Stability of Exploratory Underwater Vehicles)

  • 윤점동
    • 한국항해학회지
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    • 제11권1호
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    • pp.93-106
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    • 1987
  • Nowadays natural resources on shore have been almost exhausted all over the world and mankind is beginning searching for unexploited resources on the bed of deep-sea floor. In exploring mineral resources and etc. in the ground of sea-bed, a sumbersible craft is one of the most important tools. These days, the stage of the technique of building and operating an exploring submersible craft is almost alike that of building and operating an airplane in the first years of the nineteen-twenties. At the present time, the problems arising in building and operating a submersible craft can be divided into four parts as follows; 1. How to build a hull that can bear high pressure under deep sea level. 2. How to decide the necessary facilities to be put on it. 3. How to decide the scope of stabilities and maneuvering characteristics of it. 4. On what sea conditions, the devices of launching and recovering it should be designed on the mother-ship. In this paper treating one of the third problems the author made a mathematic formula that can be useful in deciding the scope of dynamic course stability on the vertical plane and actually calculated the onset speed of pitch instability of an exploring craft. With the above mentioned calculations the author demonstrated that the value of $Z_g$ and the speed of a submerged craft are the most important factors in decideing the scope of dynamic stability on the vertical plane.

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절리암반사면의 안정해석 방법에 관한 비교연구 (A Comarative study on slope stability modeling of highly fractured rock slopes)

  • 유충식;김선빈;양기호;정하승
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.434-443
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    • 2009
  • Slope stability analysis is an essential part of rock slope design. For highly fractured rock, the limit equilibrium method (LEM) based slope stability analysis with a circular failure surface is often carried out assuming the rock mass behaves more or less as a continuum. This paper examines first, the applicability of the finite-element method (FEM) based shear strength reduction (SSR) technique for highly fractured rock slope, and second the use of Mohr-Coulomb (MC) failure criterion in conjunction with generalized Hoek-Brown (HB) failure criterion. The numerical results on a number of cases are compared in terms of the factor of safety (FS). The results indicated that the FEM-based SSR technique yields almost the same FSs from LEM, and that the MC and HB failure criteria yield almost identical FSs when the strength parameters for MC failure criterion are obtained based on the modified HB failure criterion if and only if value of the Hoek-Brown constant $m_i$ is smaller than 10 and slope angle is smaller than 1:1, otherwise MC failure criteria over-estimate the factor of safety.

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ON A GENERALIZED TRIF'S MAPPING IN BANACH MODULES OVER A C*-ALGEBRA

  • Park, Chun-Gil;Rassias Themistocles M.
    • 대한수학회지
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    • 제43권2호
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    • pp.323-356
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    • 2006
  • Let X and Y be vector spaces. It is shown that a mapping $f\;:\;X{\rightarrow}Y$ satisfies the functional equation $$mn_{mn-2}C_{k-2}f(\frac {x_1+...+x_{mn}} {mn})$$ $(\ddagger)\;+mn_{mn-2}C_{k-1}\;\sum\limits_{i=1}^n\;f(\frac {x_{mi-m+1}+...+x_{mi}} {m}) =k\;{\sum\limits_{1{\leq}i_1<... if and only if the mapping $f : X{\rightarrow}Y$ is additive, and we prove the Cauchy-Rassias stability of the functional equation $(\ddagger)$ in Banach modules over a unital $C^*-algebra$. Let A and B be unital $C^*-algebra$ or Lie $JC^*-algebra$. As an application, we show that every almost homomorphism h : $A{\rightarrow}B$ of A into B is a homomorphism when $h(2^d{\mu}y) = h(2^d{\mu})h(y)\;or\;h(2^d{\mu}\;o\;y)=h(2^d{\mu})\;o\;h(y)$ for all unitaries ${\mu}{\in}A,\;all\;y{\in}A$, and d = 0,1,2,..., and that every almost linear almost multiplicative mapping $h:\;A{\rightarrow}B$ is a homomorphism when h(2x)=2h(x) for all $x{\in}A$. Moreover, we prove the Cauchy-Rassias stability of homomorphisms in $C^*-algebras$ or in Lie $JC^*-algebras$, and of Lie $JC^*-algebra$ derivations in Lie $JC^*-algebras$.

당첨가가 한탄바이러스백신의 안정성에 미치는 영향 (Effect of Addition of Sugar on the Stability of Hantaan Virus Vaccine)

  • 성인화
    • 대한바이러스학회지
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    • 제26권2호
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    • pp.245-249
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    • 1996
  • Hantaan virus vaccine was developed in 1988 and proved effective. This vaccine is a kind of inactivated vaccine, stable for two years when stored at $2-8^{\circ}C$. Almost virus vaccines including Hantaan virus vaccine are produced and kept in fluid state, and the immumogenicity can be easily destroyed at room temperature or at higher temperature. Therefore the vaccines should be kept in the refrigerator to maintain the immunogenicity. In this study, glucose and/or lactose was added as a stabilizer into Hantaan virus vaccine to increase the stability and dried in vaccum with ethanol treatment. 5% glucose and or lactose in Hantaan virus vaccine most effectively increased the stability of vaccine and maintained the immunogenicity at least for three months at room temperature. But drying with ethanol treatment did not help increasing the stability. These results suggest that glucose and lactose could be good stabilizer of virus vaccines.

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ASYMPTOTIC BEHAVIOR OF SOLUTIONS TO STOCHASTIC 3D GLOBALLY MODIFIED NAVIER-STOKES EQUATIONS WITH UNBOUNDED DELAYS

  • Cung The Anh;Vu Manh Toi;Phan Thi Tuyet
    • 대한수학회지
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    • 제61권2호
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    • pp.227-253
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    • 2024
  • This paper studies the existence of weak solutions and the stability of stationary solutions to stochastic 3D globally modified Navier-Stokes equations with unbounded delays in the phase space BCL-∞(H). We first prove the existence and uniqueness of weak solutions by using the classical technique of Galerkin approximations. Then we study stability properties of stationary solutions by using several approach methods. In the case of proportional delays, some sufficient conditions ensuring the polynomial stability in both mean square and almost sure senses will be provided.

MCT 대체지방의 산화안정성 및 조리 적합성에 관한 연구 (A Study on the Oxidative Stability and Cooking Scientific Characteristics of Fat Substitute MCT)

  • 안명수;우나리야
    • 한국식생활문화학회지
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    • 제18권2호
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    • pp.181-191
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    • 2003
  • This study was carried on the oxidative stability and the real practice possibilities in cooking of fat replacer MCT. Nowadays, it was known that fats and oils had become causes for cardiac disease, obesity and cancer, so the new materials were needed for fat substitute that has less fat contents and low calories. The food industry concerned about fats and oils had been researched and developed new and various kinds of substitute fats. MCT(medium chain triglycerides) is one of the fat based fat substitutes used as fat replacers. The POV of com germ oil(CO), soybean oil(SO), shortening(ST), butter(BT), their blended oil with MCT 10-50%(w/w), and MCT were determined and oxidative stability by POV was compared MCT with those of them. MCT has shown higher oxidative stability than CO, SO, ST, BT, so oxidative stabilities in all kinds of blended oils become higher and higher by the increased substitution ratios. In case of bread, the volume of bread prepared with MCT(MCT bread) substituted for ST at 10-40% level(w/w) were increased a little comparing to that made of shortening(ST bread). But degree of gelatinization of MCT bread were a little lower than ST bread, at the substitute ratio above 40%, the degree of gelatinization were reduced greatly. These phenomena were sustained in 9 stored days. While baking losses of MCT breads were almost same as ST bread until 30% substitute ratio, and the appearances of MCT breads were similar to ST bread until 40% substitute ratio. Also rheological properties and color(Lab) of MCT breads had shown no different significantly from ST bread until 20% substitute ratio, but by the results of sensory evaluation, overall acceptance including appearance, color, flavor, taste, texture of MCT breads were recognized almost same as ST bread by panel until 40% substitute ratio. Depends on the above results, we can suggest that 30-40% of MCT will substitute for shortening in making bread in order to reduce fat and calories intake amounts.