• 제목/요약/키워드: Ty-4

검색결과 92건 처리시간 0.022초

정4각덕트의 입구영역에서 난류 비정상유동에 대한 이론과 실험적 연구 (A Theoretical and Experimental Study on the Developing Turbulent Unsteady Flows in the Entrance Region of a Square Duct)

  • 고영하
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권5호
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    • pp.643-651
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    • 1998
  • Turbulent unsteady flows in the entrance region of a square duct are investigated with a hot-wire anemometer system. The velocity waveforms the mean and turbulence components of the axial velocity and the entrance length are obtained as a major characteristics of the developing turbulent unsteady flows. An inviscid flow theory is presented to describe the developing axial mean velocity profiles. A good agreement is seen between the measured and theoretically predicted values. The propagation of turbulence generated near the entrance of the square duct is satisfactorily approximated by an empirical correlation of the propagation of turbulence proposed so far. The local turbulence intensi-ty is found to be a little smaller in the accelerating phase than in the decelerating phase. The entrance length is about 60 times as large the hydraulic diameter.

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On Common Fixed Prints of Expansive Mappings

  • Kang, Sin-Min;Park, Bae-Hun
    • 한국수학교육학회지시리즈A:수학교육
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    • 제29권1호
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    • pp.41-45
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    • 1990
  • S. Z. Wang, B. Y. Li, Z. M. Gao and K. Iseki proved some fixed point theorems on expansion mappings, which correspond some contractive mappings. In a recent paper, B. E. Rhoades generalized the results for in of mappings. In this paper, we obtain the following theorem, which generalizes the result of B. E. Rhoades. THEOREM. Let A, B, S and T be mappings from a complete metric space (X, d) into itself satisfying the following conditions: (1) ${\Phi}$(d(A$\chi$, By))$\geq$d(Sx, Ty) holds for all x and y in X, where ${\Phi}$ : R$\^$+/ \longrightarrowR$\^$+/ is non-decreasing, uppersemicontinuous and ${\Phi}$(t) < t for each t > 0, (2) A and B are surjective, (3) one of A, B, S and T is continuous, and (4) the pairs A, S and B, T are compatible. Then A, B, S and T have a unique common fixed point in X.

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한 종합병원 약품 재고관리를 위한 수요예측(需要豫測) (Demand Forecasting for Developing Drug Inventory Control Model in a University Hospital)

  • 손명세
    • Journal of Preventive Medicine and Public Health
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    • 제16권1호
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    • pp.113-120
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    • 1983
  • The main objective of this case study is to develop demand forecasting model for durg inventory control in a university hospital. This study is based on the pertinent records during the period of January 1975 to August 1981 in the pharmacy and stock departments of the hospital. Through the analysis of the above records the author made some major findings as follows: 1. In A.B.C. classification, the biggest demand (A class) consists of 9 items which include 6 items of antibiotics. 2. Demand forecasting level of an index or discrepancy in A class drug compared with real demand for 6 months is average 30.4% by X-11 Arima method and 84.6% by Winter's method respectively. 3. After the correcting ty the number of bed, demand forecasting of drug compared with real demand for 6 months is average 23.1% by X-11 Arima method and 46.6% by Winter's method respectively.

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Penicillium chrysogenum에 의한 ${\beta}-Lactamase$ 생성(生成) (Extracellular Production of ${\beta}-Lactamase$ by Penicillium chrysogenum)

  • 이삼환;허규정;김은수;이길수
    • 한국균학회지
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    • 제8권1호
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    • pp.63-68
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    • 1980
  • ${\beta}-Lactamase$ was isolated from the culture filtrate of the penicillin producing strain, Penicillium chrysogenum Q176. When the pH of the medium was adjusted to 5.0 at the start of culture, a rapid increase in pH accompanied by the synthesis of penicillin was observed in the first $2{\sim}4$ days. When the pH of medium was brought to 6.0 or 7.0 the opposite was observed: high yield of the enzyme and little of the antibiotics in the medium. The optimum enzyme activi­ty was at a temperature of $40^{\circ}C$ and around pH 7.0. A partially purified enzyme was assayed on several different substrates including penicillins V and G, 6-aminopenicillanic acid, cephalospo­rin C. The V max values calculated were 24.5, 20.4, 7.6, and 6.1 mmoles/hour, and the $K_m$, values were 16.4, 12.6, 7.5, and 6.9 mM in the order given.

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경북지방유래 추백리 양성계에서의 균분리 및 혈청역가 추이 (The variation of serological titers on the chickens infected pullorum disease from Kyongbuk provinces)

  • 김영환;김경희;우용구;장영술;조민희;김수웅
    • 한국동물위생학회지
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    • 제20권1호
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    • pp.19-26
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    • 1997
  • The present study was conducted to investigate the general epidemiological situations with 18-pullorum infected chickens from Kyongbuk provinces during the period from June 1995 to January 1996. On the Salmonella pullorum isolation tests by rectal swab culture method from infected chickens (386-samples), any Salmonella spp was not isolated from infected live-birds. But 2-S pullorum were isolated of 2-dead chickens(33.3% ) from 6-dead chickens which were positively reacted by serological tests. On the other hand, we could not isolated any Salmonella spp. in any parts of egg-contents ; egg-shell, egg-white and egg-yolks with 25-infected bird eggs. On the tests of antibiogram, 2-S pullorum strains were highly sensitive to GM, AM, SXT, CZ, K, FIM, ENR, C, AN, N, NN, LIN+SP, CF, TE and PB, respectively and intermediate sensitive to the CB, CFP, CL, S, P and XNL. But 2-strains were resistant to CC, DP, E, L, OX, TLA and TyLO. In the serological tests, pullorum antibody titers of 18-infected birds was from 2.76 to 9.18 with average by the microplate test. During the 6-months, pullorum antibody average titers were not changed generally. To validate the effects of the antimicrobial agent treatments to the serological antibody titers, infected 6-chickens was medicated with 0.5%-futazolidone. The titer of premeditated birds was average 4.26 but after medication with furazolidone, the titers of treated 6-birds was average 4.08.

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MODIFIED KRASNOSELSKI-MANN ITERATIONS FOR NONEXPANSIVE MAPPINGS IN HILBERT SPACES

  • Naidu, S.V.R.;Sangago, Mengistu-Goa
    • Journal of applied mathematics & informatics
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    • 제28권3_4호
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    • pp.753-762
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    • 2010
  • Let K be a nonempty closed convex subset of a real Hilbert space H. Let T : K $\rightarrow$ K be a nonexpansive mapping with a nonempty fixed point set Fix(T). Let f : K $\rightarrow$ K be a contraction mapping. Let {$\alpha_n$} and {$\beta_n$} be sequences in (0, 1) such that $\lim_{x{\rightarrow}0}{\alpha}_n=0$, (0.1) $\sum_{n=0}^{\infty}\;{\alpha}_n=+{\infty}$, (0.2) 0 < a ${\leq}\;{\beta}_n\;{\leq}$ b < 1 for all $n\;{\geq}\;0$. (0.3) Then it is proved that the modified Krasnoselski-Mann iterative sequence {$x_n$} given by {$x_0\;{\in}\;K$, $y_n\;=\;{\alpha}_{n}f(x_n)+(1-\alpha_n)x_n$, $n\;{\geq}\;0$, $x_{n+1}=(1-{\beta}_n)y_n+{\beta}_nTy_n$, $n\;{\geq}\;0$, (0.4) converges strongly to a point p $\in$ Fix(T} which satisfies the variational inequality

    $\leq$ 0, z $\in$ Fix(T). (0.5) This result improves and extends the corresponding results of Yao et al[Y.Yao, H. Zhou, Y. C. Liou, Strong convergence of a modified Krasnoselski-Mann iterative algorithm for non-expansive mappings, J Appl Math Com-put (2009)29:383-389.

Branched Chain 아미노산과 대사산물들이 Serratia marcescens ATCC 25419 Acetolactate Synthase의 생합성에 미치는 영향 (The Effects of Branched Chain Amino Acids and Small Metabolites on the Biosynthesis of Acetolactate Synthase in Serratia rnarcescens ATCC 25419)

  • 최병범;김승수
    • 한국미생물·생명공학회지
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    • 제20권2호
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    • pp.115-121
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    • 1992
  • 최소 배지에 여러가지 아미노산들을 첨가하여 배양한 Serratia marcescens ATCC 25419 세포 추출물에서 acetolactate syhthase(ALS)의 비활성도를 0.5mM에서 40 증가시킨 반면 8mM에서 60, 20mM에서 90 감소시켰다. Valine은 효소의 비활성도를 2-4 mM에서 20-40 정도 증가시켰고 20mM의 높은 농도에서 10 정도 감소시켰다.

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$Tb^{3+}$$Eu^{3+}$로 활성화된 $Al_3GdB_4O_{12}$ 형광체의 발광특성 (Photoluminance Properties of $Al_3GdB_4O_{12}$ Phosphors Activated by $Tb^{3+}$and $Eu^{3+}$)

  • 김기운;김성우;이임렬
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.594-597
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    • 1999
  • The new green and red phosphors for PDP application activated by T $b^{3+}$ and E $u^{3+}$ were synthesized, and their photoluminance properties were investigated. It was found that the brightness of $Al_3$Gd $B_4$ $O_{12}$ :T $b^{3+}$ green phosphor under 147nm VUV irradiation was higher than that of commercial Z $n_2$ $SiO_4$:M $n^{2+}$ phosphor. But the emitting intensity of A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ red phosphor was inferior to the commercial (Y,Gd)B $O_3$:E $u^{3+}$. $Al_3$Gd $B_4$ $O_{12}$ Phosphor had a strong excitation band at 160nm associated with the host absorption, and also the photoluminance excitation intensity of $Al_3$Gd $B_4$ $O_{12}$ :T $b^{3+}$ was higher than that of Z $n_2$ $SiO_4$:M $n^{2+}$, but the intensity of $Al_3$Gd $B_4$ $O_{12}$ :E $u^{3+}$ phosphor was smaller than (Y,Gd)B $O_3$:E $u^{3+}$ phosphor In the VUV range. C $e^{3+}$ co-doping in A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ and substitution of $Al^{3+}$ by G $a^{3+}$ A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ phosphor were tried, but they did not improved the optical property .d the optical property .ty .

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제2감수분열 중기에서 발달정지된 돼지 난자의 인위적 난활성 (Artificial Activation of Pig Oocytes Arrested at meiotic Metaphase II)

  • ;김재환
    • 한국가축번식학회지
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    • 제20권4호
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    • pp.395-412
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    • 1997
  • 포유동물의 난자는 제 2 감수분열 중기에서 배란되어 수정된다. 일반적으로 포유동물에서의 수정은 inositol triphosphate (IP3) 또는 cyclic adenosine diphosphoribose (cADPr)에 의해 조절되어지는 세포질내 칼슘변화에 의해 일어난다. 난활성이 일어나면 세포질내 고농도의 MPF (maturation promotion factor)는 감소하고, 전핵이 형성되고, cytoskeleton이 재구성되고, 단백질합성이 조절되어진다. 이러한 모든 과정이 정상적으로 일어난 후 수정란은 종특이한 발달경로로 배발달을 시작한다. 본 논문에서는 돼지난자의 인위적인 난활성 유도방법에 대해서 설명하고자 한다. 신호전달(signal transduction) 경로에 의한 하나의 기전이 돼지난자에서 확인되었는데, 이 경로의 자극은 난활성으로 이루어진다. 또한 전기자극에 의한 난활성방법에 의해 12일까지 정상배 발달이 이루어진다고 보고되고 있다. 향후 연구에서는 정자가 어떠한 기전에 의해서 배발달을 시작하게 하는지를 밝혀내야 한다고 본다.

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곤충병원성 선충에서 분리한 공생세균의 안정화 및 항진균활성 (Stabilization and Antifungal Activity of Isolated Symbiotic Bacteria from Entomopathogenic Nematodes)

  • 강동희;김효현;남욱호;김현수
    • KSBB Journal
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    • 제30권3호
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    • pp.132-139
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    • 2015
  • In order to use the symbiotic bacteria from ethomophatogenic nematodes as a biological control agent for agriculture, the cultural condition for maintaining phase I and antifungal activity was investigated. Symbiotic bacteria (SB) 1 stain from nematodes were selected from the three strains isolated from entomopathogenic nematodes. The growth of the SB 1 strain in NB, TSB, TY and YS medium was higher than that of the SB 2 and SB 3 strain. The packed cell volume of the SB 1 strain was reduced in NB medium which showed radical pH change. Phase I of the SB 1 strain was maintained in TSB medium after being stored for 2 weeks at $4^{\circ}C$. Culture broth with the SB 1 strain in TSB medium for 6 days and 7 days showed antifungal activities against Rhizoctonia solani KACC 40142, Botrytis cinerea Pers. KACC 40854, and Botrytis cinerea Pers. KACC 41008. Culture broth with the SB 1 strain in TSB medium containing 100 mM L-proline for 5 days showed antifungal activities against Rhizoctonia solani KACC 40142, and Botrytis cinerea Pers. KACC 40854.