• Title/Summary/Keyword: ${\Delta}T$

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EXISTENCE OF THREE POSITIVE PERIODIC SOLUTIONS OF NEUTRAL IMPULSIVE FUNCTIONAL DIFFERENTIAL EQUATIONS

  • Liu, Yuji;Xia, Jianye
    • Journal of applied mathematics & informatics
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    • v.28 no.1_2
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    • pp.243-256
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    • 2010
  • This paper is concerned with the neutral impulsive functional differential equations $$\{{x'(t)\;+\;a(t)x(t)\;=\;f(t,\;x(t\;-\;\tau(t),\;x'(t\;-\;\delta(t))),\;a.e.\;t\;{\in}\;R, \atop {\Delta}x(t_k)\;=\;b_kx(t_k),\;k\;{\in}\;Z.$$ Sufficient conditions for the existence of at least three positive T-periodic solution are established. Our results generalize and improve the known ones. Some examples are presented to illustrate the main results.

Oscillatory Behavior of Linear Neutral Delay Dynamic Equations on Time Scales

  • Saker, Samir H.
    • Kyungpook Mathematical Journal
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    • v.47 no.2
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    • pp.175-190
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    • 2007
  • By employing the Riccati transformation technique some new oscillation criteria for the second-order neutral delay dynamic equation $$(y(t)+r(t)y({\tau}(t)))^{{\Delta}{\Delta}}+p(t)y(\delta(t))=0$$, on a time scale $\mathbb{T}$ are established. Our results as a special case when $\mathbb{T}=\mathbb{R}$ and $\mathbb{T}=\mathbb{N}$ improve some well known oscillation criteria for second order neutral delay differential and difference equations, and when $\mathbb{T}=q^{\mathbb{N}}$, i.e., for second-order $q$-neutral difference equations our results are essentially new and can be applied on different types of time scales. Some examples are considered to illustrate the main results.

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The assessment of oriental medicine treatment for cervical sprain from traffic accident using DITI (DITI를 이용한 교통사고 환자의 한의학적인 치료평가)

  • Lee, Chang-Hoon;Cho, Jung-Hoon;Jang, Jun-Bock;Lee, Kyung-Sub;Hwang, Jae-Ho
    • Journal of Oriental Medical Thermology
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    • v.4 no.1
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    • pp.39-44
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    • 2005
  • Purpose: This study is to assess oriental medicine treatment for cervical sprain from traffic accident using DITI. Methods: 21 patients who hospitalized in the Kangnam Korean Hospital, KyungHee Univ. from March 1, 2004 to September 30, 2005 diagnosed as cervical sprain from traffic accident were participated in this study. They received acupuncture treatment, Herb medicine, ICT-Tx, and Nega-Tx during the admission period. We checked temperature of neck(A area) and whole back(B area) and ${\Delta}T$ were calculated at admission date(pre-Tx group, ${\Delta}T1$) and discharged date(post-Tx group, ${\Delta}T2$). Results: ${\Delta}T2$ decreased significantly in post-Tx group compared with ${\Delta}T1$ in pre-Tx group Conclusion: Oriental medicine treatment can be the effective way to treat cervical sprain from traffic accident. and DITI can be useful instrument to assess oriental medicine treatments.

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홧병환자에서 DITI의 진단활용

  • Ko, Chang-Nam;Lee, Kyung-Sub
    • Journal of Oriental Medical Thermology
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    • v.1 no.1
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    • pp.13-19
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    • 2002
  • Objectives : This study was performed to apply thermography as an method in diagnosis of hwabyung patients. We studied 11 Hwabyung patients who visited to chronic diseases center and circulatory oriental internal medicine of Kangnam oriental medicine hospital and 11 patients control group. Methods : Diagnosis of Hwabyung was based on the dignostic criteria of Hwabyung. The temperature was measured on Chonjung(CV17) Shimsu(B15), Kansu(B18), Kyonjong(G21) in each group. The ${\Delta}T$ was measured between Chonjung(CV17) and Chungjong(CV16), left and right Chungjong(CV16), Shimsu(B15), Kansu(B18), Kyonjong(G21) in each group. We compared the ${\Delta}T$ and DITI types between patients and control group. Results : The ${\Delta}T$ between left and right Chungjong(CV16), Shimsu(B15), Kansu(B18), Kyonjong(G21) were not statistically significant. But the ${\Delta}T$ between Chonjung(CV17) and Chungjong(CV16) was statistically significant(P<0.05) in each group. In control group, DITI type was straight 36%, diamond 27%, multiple small spot 18%, others 18%. In Hwabyung patients group, DITI type was inverse triangle 64%, multiple small spot 9.1%, round 9.1%. Conclusions : The ${\Delta}T$ between Chonjung(CV17) and Chungjong(CV16) and DITI type is considered useful diagnostic methods on Hwabyung patients.

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Service Life Analysis of Control Valve for Automatic Turbine Startup of Thermal Power Plant (화력 발전소 증기 터빈의 자동기동을 위한 주증기 제어 밸브 수명해석)

  • Kim, Hyo-Jin;Kang, Yong-Ho;Shin, Cheul-Gyu;Park, Hee-Sung;Yu, Bong-Ho
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.7-12
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    • 2000
  • The automatic turbine startup system provides turbine control based on thermal stress. During the startup, control system monitors and evaluates main components of turbine using damage mechanism and life assessment. In case of valve chest, the temperature of inner/outer wall is measured by thermo-couples and the safety of these values are evaluated by using allowable ${\Delta}T$ limit curve during the startup. Because allowable ${\Delta}T$ limit curve includes life assessment, it is possible to apply this curve to turbine control system. In this paper, low cycle fatigue damage and combined rupture and low cycle fatigue damage criterion proposed for yielding the allowable ${\Delta}T$ limit curve of CV(control valve) chest. To calculate low cycle fatigue damage, the stress analysis of valve chest has peformed using FEM. Automatic turbine startup to assure service life of CV was achieved using allowable ${\Delta}T$ limit curve.

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Tocotrienol and Tocopherol Content in Various Plant Seeds (몇 가지 작물 종실의 Tocotrienol과 Tocopherol 함량)

  • 박경열;강창성;이용선;이영현;이영상
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.3
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    • pp.207-210
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    • 2004
  • Vitamin E, consisting of tocotrienols ($\textrm{T}_3$) and tocopherols ($\textrm{T}$) is well-known nutraceutical compound for its antioxidant, anticancer and cholesterol-low-ering activity. The contents of alpha ($\alpha\textrm{-}$), beta ($\beta\textrm{-}$), gamma ($\gamma\textrm{-}$) and delta ($\delta\textrm{-}$) tocotrienols and tocopheyols in some Korean crop seeds were evaluated by using HPLC after saponification. Among tested crops, total 73 contents (mg/110g) were purple perilla 25.06, barley 4.50, corn 3.54, iris 3.04, adlay 2.58, safflower 0.12. Other crops including 5 soybean cultivars, kidneybean, sunflower and perilla contained no tocotrienols. Regarding $\textrm{T}_3$ isomers, $\beta\textrm{-}$$\textrm{T}_3$ were rut observed in adlay and corn, and $\delta$-$\textrm{T}_3$ were not in iris aid purple perilla, while safflower exhibited no detectable $\alpha\textrm{-}$, $\beta\textrm{-}$ and $\delta\textrm{-}$$\textrm{T}_3$. Total T contents (mg/100g) were high in iris (51.82), perilla (40.90), soybean (34.11), sunflower (20.88), and they all contained all $\alpha\textrm{-}$, $\beta\textrm{-}$, $\gamma\textrm{-}$ and $\delta\textrm{-}$ tocopterol isomers. Total Vit E contents (T + $\textrm{T}_3$, mg/100g) were iris 54.86, purple perilla 41.80, perilla 40.90, soybean 34.11, sunflower 20.88, safflower 14.73, corn 11.49, evening-primrose 10.07, barley 7.48, adlay 6.24 and kidneybean 5.27.

Biochemical and Molecular Biological Studies on the DNA Replication of Bacteriophage T7 (Bacteriophage T7의 유전자 복제기작에 관한 생화학적, 분자생물학적 특성 연구)

  • KIM Young Tae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.2
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    • pp.209-218
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    • 1995
  • Bacteriophage T7 gene 2.5 protein, a single-stranded DNA binding protein, has been implicated in T7 DNA replication, recombination, and repair. Purified gene 2.5 protein has been shown to interact with the phage encoded gene 5 protein (DNA polymerase) and gene 4 proteins (helicase and primase) and stimulates their activities. Genetic analysis of T7 phage defective in gene 2.5 shows that the gene 2.5 protein is essential for T7 DNA replication and growth. T7 phage that contain null mutants of gene 2.5 were constructed by homologous recombination. These mutant phage $(T7\Delta2.5)$ cannot grow in Escherichia coli. After infection of E. coli with $T7\Delta2.5$, host DNA synthesis is shut off, and $T7\Delta2.5$ DNA synthesis is reduced to less than $1\%$ of wild-type phage DNA synthesis (Kim and Richardson, 1993, Proc. Natl. Aca. Sci. USA, 90, 10173-10177). A truncated gene 2.5 protein $(GP2.5-\Delta21C)$ deleted the 21 carboxyl terminal amino acids was constructed by in vitro mutagenesis. $GP2.5-\Delta21C$ cannot substitute for wild-type gene 2.5 protein in vivo; the phage are not viable and exhibit less than $1\%$ of the DNA synthesis observed in wild-type phage-infected cells. $GP2.5-\Delta21C$ has been purified to apparent homogeneity from cells overexpressing its cloned gene. Purified $GP2.5-\Delta21C$ does not physically into「act with T1 gene 4 protein as measured by affinity chromatography and immunoblot analysis. The mutant protein cannot stimulate T7 gene 4 protein activity on RNA-primed DNA synthesis and primer synthesis. These results suggest that C-terminal domain of gene 2.5 protein is essential for protein-protein interactions.

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STABILITY FOR A VISCOELASTIC PLATE EQUATION WITH p-LAPLACIAN

  • Park, Sun Hye
    • Bulletin of the Korean Mathematical Society
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    • v.52 no.3
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    • pp.907-914
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    • 2015
  • In this paper, we consider a viscoelastic plate equation with p-Laplacian $u^{{\prime}{\prime}}+{\Delta}^2u-div({\mid}{\nabla}u{\mid}^{p-2}{\nabla}u)+{\sigma}(t){\int}_{0}^{t}g(t-s){\Delta}u(s)ds-{\Delta}u^{\prime}=0$. By introducing suitable energy and Lyapunov functionals, we establish a general decay estimate for the energy, which depends on the behavior of both ${\sigma}$ and g.

CHARACTERIZATIONS OF STABILITY OF ABSTRACT DYNAMIC EQUATIONS ON TIME SCALES

  • Hamza, Alaa E.;Oraby, Karima M.
    • Communications of the Korean Mathematical Society
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    • v.34 no.1
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    • pp.185-202
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    • 2019
  • In this paper, we investigate many types of stability, like (uniform stability, exponential stability and h-stability) of the first order dynamic equations of the form $$\{u^{\Delta}(t)=Au(t)+f(t),\;\;t{\in}{\mathbb{T}},\;t>t_0\\u(t_0)=x{\in}D(A),$$ and $$\{u^{\Delta}(t)=Au(t)+f(t,u),\;\;t{\in}{\mathbb{T}},\;t>t_0\\u(t_0)=x{\in}D(A),$$ in terms of the stability of the homogeneous equation $$\{u^{\Delta}(t)=Au(t),\;\;t{\in}{\mathbb{T}},\;t>t_0\\u(t_0)=x{\in}D(A),$$ where f is rd-continuous in $t{\in}{\mathbb{T}}$ and with values in a Banach space X, with f(t, 0) = 0, and A is the generator of a $C_0$-semigroup $\{T(t):t{\in}{\mathbb{T}}\}{\subset}L(X)$, the space of all bounded linear operators from X into itself. Here D(A) is the domain of A and ${\mathbb{T}}{\subseteq}{\mathbb{R}}^{{\geq}0}$ is a time scale which is an additive semigroup with property that $a-b{\in}{\mathbb{T}}$ for any $a,b{\in}{\mathbb{T}}$ such that a > b. Finally, we give illustrative examples.

Range Kernel Orthogonality and Finite Operators

  • Mecheri, Salah;Abdelatif, Toualbia
    • Kyungpook Mathematical Journal
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    • v.55 no.1
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    • pp.63-71
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    • 2015
  • Let H be a separable infinite dimensional complex Hilbert space, and let $\mathcal{L}(H)$ denote the algebra of all bounded linear operators on H into itself. Let $A,B{\in}\mathcal{L}(H)$ we define the generalized derivation ${\delta}_{A,B}:\mathcal{L}(H){\mapsto}\mathcal{L}(H)$ by ${\delta}_{A,B}(X)=AX-XB$, we note ${\delta}_{A,A}={\delta}_A$. If the inequality ${\parallel}T-(AX-XA){\parallel}{\geq}{\parallel}T{\parallel}$ holds for all $X{\in}\mathcal{L}(H)$ and for all $T{\in}ker{\delta}_A$, then we say that the range of ${\delta}_A$ is orthogonal to the kernel of ${\delta}_A$ in the sense of Birkhoff. The operator $A{\in}\mathcal{L}(H)$ is said to be finite [22] if ${\parallel}I-(AX-XA){\parallel}{\geq}1(*)$ for all $X{\in}\mathcal{L}(H)$, where I is the identity operator. The well-known inequality (*), due to J. P. Williams [22] is the starting point of the topic of commutator approximation (a topic which has its roots in quantum theory [23]). In [16], the author showed that a paranormal operator is finite. In this paper we present some new classes of finite operators containing the class of paranormal operators and we prove that the range of a generalized derivation is orthogonal to its kernel for a large class of operators containing the class of normal operators.