• Title/Summary/Keyword: $({\Delta}T\

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이중 경사 자장 에코와 일반 경사 자장 에코 펄스열로부터의 $\Delta{R}_1$$\Delta{R}_2$에 대한 컴퓨터 가상 실험

  • 김대홍;김은주;서진석
    • Proceedings of the KSMRM Conference
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    • 2002.11a
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    • pp.102-102
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    • 2002
  • 목적:$\Delta{R}_1$$\Delta{R}_2\;^{*}$$T_1$, $T_2\;^{*}$로부터 직접 구해야 하지만, 시간 해상도 때문에 각각 $T_1$, $T_2\;^{*}$ 강조영상으로부터 구하는 것이 일반적이다. $T_1$, $T_2\;^{*}$ 강조영상으로부터 얻은 $\Delta{R}_1$$\Delta{R}_2\;^{*}$ 과 이중 경사 자장에코 펄스열로부터 얻은 $\Delta{R}_1$$\Delta{R}_2\;^{*}$ 를 컴퓨터 가상 실험을 통해서 비교한다. 강조 영상의 신호 세기만으로는 정확한 관류 정보를 얻을 수 없음을 보이고자 한다. 대상 및 방법: 알려진 $\Delta{R}_1$$\Delta{R}_2\;^{*}$ 값을 이용하여 강조영상으로부터 구할 수 있는 $\DeltaR_1$$\Delta{R}_2\;^{*}$ 을 농도에 따라서 가상실험으로 구하고, 이 값과 이중 경사 자장 에코 펄스열로부터 구할 수 있는 $\Delta{R}_1$$\Delta{R}_2\;^{*}$를 가상실험으로 구해서 비교한다.

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T-NEIGHBORHOODS IN VARIOUS CLASSES OF ANALYTIC FUNCTIONS

  • Shams, Saeid;Ebadian, Ali;Sayadiazar, Mahta;Sokol, Janusz
    • Bulletin of the Korean Mathematical Society
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    • v.51 no.3
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    • pp.659-666
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    • 2014
  • Let $\mathcal{A}$ be the class of analytic functions f in the open unit disk $\mathbb{U}$={z : ${\mid}z{\mid}$ < 1} with the normalization conditions $f(0)=f^{\prime}(0)-1=0$. If $f(z)=z+\sum_{n=2}^{\infty}a_nz^n$ and ${\delta}$ > 0 are given, then the $T_{\delta}$-neighborhood of the function f is defined as $$TN_{\delta}(f)\{g(z)=z+\sum_{n=2}^{\infty}b_nz^n{\in}\mathcal{A}:\sum_{n=2}^{\infty}T_n{\mid}a_n-b_n{\mid}{\leq}{\delta}\}$$, where $T=\{T_n\}_{n=2}^{\infty}$ is a sequence of positive numbers. In the present paper we investigate some problems concerning $T_{\delta}$-neighborhoods of function in various classes of analytic functions with $T=\{2^{-n}/n^2\}_{n=2}^{\infty}$. We also find bounds for $^{\delta}^*_T(A,B)$ defined by $$^{\delta}^*_T(A,B)=jnf\{{\delta}&gt;0:B{\subset}TN_{\delta}(f)\;for\;all\;f{\in}A\}$$ where A, B are given subsets of $\mathcal{A}$.

Comparison of the Diagnostic Validity of Real and Absolute Skin Temperature Differences for Complex Regional Pain Syndrome (복합부위통증증후군 진단 시 좌우 체온 차이의 실제값과 절대값의 진단적 타당도 비교)

  • Nahm, Francis Sahngun;Lee, Pyung Bok;Park, Soo Young;Kim, Yong Chul;Lee, Sang Chul
    • The Korean Journal of Pain
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    • v.22 no.2
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    • pp.146-150
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    • 2009
  • Background: A skin temperature difference is one of the variables used in the diagnosis of complex regional pain syndrome. However, there have been no reports as to whether the real (${\Delta}T$) or absolute value ($|{\Delta}T|$) of skin temperature differences should be used in the diagnosis of complex regional pain syndrome. This study was conducted to compare the diagnostic validity of ${\Delta}T$ with $|{\Delta}T|$ for complex regional pain syndrome using receiver operating characteristic curves (ROC). Methods: Infrared thermographic images were obtained from the 144 patients who were suspected to have CRPS in a unilateral limb. After ${\Delta}T$ and $|{\Delta}T|$ calculation from the thermographic image, ROCs of ${\Delta}T$ and $|{\Delta}T|$ were developed, and the areas under the curve (AUC) for the ROC curves were compared. Results: AUCs of ${\Delta}T$ and $|{\Delta}T|$ were 0.520 and 0.746 respectively, this difference was statistically significant (P < 0.001). Conclusions: Absolute skin temperature difference shows greater validity in the diagnosis of CRPS than ${\Delta}T$. Therefore, $|{\Delta}T|$ is more useful when comparing the skin temperature of CRPS patients.

Natural Convection Heat Transfer in Rectangular Air Enclosures With Adiabatic and Isothermal Horizontal Boundary Conditions (단열 및 등온수평 경계조건을 갖는 직각 밀폐용기내 공기의 자연대류 열전달)

  • 이진호;김무현;모정하
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.1
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    • pp.207-213
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    • 1990
  • Natural convection heat transfer in rectangular air enclosure was studied interferometrically and numerically for the use of adiabatic and constant temperature horizontal boundary conditions. In the isothermal horizontal boundary case with the temperature difference ratio, .DELTA. $T_{v/}$.DELTA. $T_{H}$ .simeq. 1 temperature distribution in the enclosure is strongly stratified and the average Nusselt Number is higher than that of adiabatic horizontal boundary case.ase.

Prediction of Affinity between Membrane and Esters Using Solubility Parameter (용해도 파라미터에 의한 막과 esters 간의 친화도 예측)

  • Song, Kun-Ho;Lee, Kwang-Rae
    • Membrane Journal
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    • v.24 no.6
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    • pp.484-490
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    • 2014
  • To find out the feasibility of the separating/enriching esters from aqueous solution using FASs (Fluoloalkyl-silanes-coupling agent)-surface modified hydrophobic membrane, the solubility parameter of FASs was obtained and compared with those of esters and water. The value of the solubility parameter of FASs (${\delta}_t=16.9$) was almost same with those of esters (ethyl acetate ${\delta}_t=18.1$, propyl acetate ${\delta}_t=18.0$, ethyl propionate ${\delta}_t=17.9$, butyl acetate ${\delta}_t=17.4$, ethyl butyrate ${\delta}_t=17.0$). However, the calculated value of the solubility parameter of water was ${\delta}_t=47.8$, which was far from the value of the solubility parameter of FASs (${\delta}_t=16.9$). This means that the FASs-modified membrane has a much higher affinity to esters than water. The experimental results of permeation flux of esters used in this study showed that the order of permeation flux predicted by the solubility parameter was almost coincide with experimental results. It might be concluded that the solubility parameter may be applicable for a separating/enriching flavors from aqueous natural-flavor solution, in which esters are main components of natural flavors.

A temperature adjustment process of stratified fluid induced simultaneously by sidewall thermal variation and vertical through-flow (용기의 온도변화와 수직관류가 동시에 작용하는 성층유체의 과도유동)

  • Park, Jun-Sang;Hyun, Jae-Min
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.450-455
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    • 2001
  • An analytical study is made of transient adjustment process of an initially stationary, stably-stratified fluid in a square. The boundary walls are highly-conducting. The overall Rayleigh number $R_a$ is large. Considerations are given to both opposing (${\delta}w/{\delta}T>0$) and cooperating (${\delta}w/{\delta}T<0$) configurations. The flow character in opposing configuration can be classified into (a) a forced-convection dominaut mode (${\delta}w/{\delta}T>1/\sqrt{2}$), (b) a buoyancy-convection dominant mode ($0<{\delta}w/{\delta}T<1/\sqrt{2}$), and (c) a static mode (${\delta}w/{\delta}T{\cong}1/\sqrt{2}$). Global evolutionary processes are depicted. and physical rationalizations are provided.

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The Distribution of ${\gamma}{\delta}$ T Cells in Tuberculous Lymphadenopathy (결핵성 림프절에서 ${\gamma}{\delta}$ T 림프구의 분포에 관한 연구)

  • Shim, Tae-Sun;Yoo, Chul-Gyu;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.5
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    • pp.484-488
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    • 1994
  • Background : The antigen-specific receptor on the surface of most peripheral T lymphocytes is a disulfide-linked heterodimer composed of $\alpha$ and $\gamma$ subunits, noncovalently associated with CD3 polypeptides. Recently, a novel type of CD3-associated heterodimer was described on a T cell subset that does not express CD4 or CD8 molecules. This second type of TCR dimer is composed of chains encoded for by the $\gamma$- and $\delta$-TCR genes. These cells may exert both cytotoxic and lymphokine producing functions. Although it was reported that some ${\gamma}{\delta}$-TCR might recognize an MHC-linked determinant, the funεtion or physiologic ligand for this new receptor is not yet clear. It was found that ${\gamma}{\delta}$-TCR can react with 65 kD heat shock protein of M. tuberculosis, which suggests the possible protective role of ${\gamma}{\delta}$ T lymphocytes against tuberculosis. In our previous study, there was neither the increase in number nor the functional activation of ${\gamma}{\delta}$ T cells in the peripheral blood from patients with pulmonary tuberculosis. Now we report the distribution of ${\gamma}{\delta}$ T cells in the regional sites of M. tuberculosis infection, especial1y tuberculous lymphadenitis. Methods : Lymph nodes from patients with pathologically-proven tuberculous lymphadenopathy (n=5) and reactive hyperplasia (n=3) were used. Tissues were frozen in liquid nitrogen immediately after removal and stored below $-70^{\circ}C$. The cryostat sections of these frozen specimens were stained with anti-Leu-4 Ab, Identi-T TCR ${\delta}1$, and Identi-T ${\beta}F1$. The number of positively stained cells were counted at high power field. Results : The infiltration of ${\gamma}{\delta}$ T cells was significantly higher in the lymph nodes from patients with tuberculous lymphadenopathy than that with reactive hyperplasia ($16.3{\pm}10.3%$ vs. $1.7{\pm}1.5%$). Conclusion : These results suggest that ${\gamma}{\delta}$) T cells may play a role in the defense against M. tuberculosis infection, especially in the regional sites of infection.

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Trans Fatty Acid Isomers of Processed Foods Commonly Consumed in Korea (한국인 상용 가공식품의 trans 지방산 이성체)

  • 노경희;원미숙;송영선
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.3
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    • pp.325-337
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    • 2003
  • This study was designed to determine the distribution of trans fatty acids (tFAs) isomers of Processed foods commonly consumed in Korea. The tFAs positional isomers were analyzed using GC/MS spectrometer with HP-23 cis/trans FAME, capillary column (50m $\times$ 0.20 mm, id., 0.2 ${\mu}{\textrm}{m}$ film thickness) for 41 food samples. TFAs isomers were identified by comparing retention time with standards and GC/MS spectrum. In margarines, the content of tFAs ranged from 4.0% to 25.16% and the most abundant positional isomer of tFAs was C18:1 $\Delta$9t. In oils and fats, lards contained higher levels of tFAs (5.70~16.54%) than shortenings (6.77~10.55%). Shortenings contained higher levels of C18:1 $\Delta$9t (3.1~5.1%) than lard (1.6~4.3%), but corn oils had no tFAs. In seasonings, mayonnaise had no C16:1 $\Delta$9t, whereas C18:3t was detected. The content of tFAs in confectioneries was wide (16.20~52.16%). Among them, instant popcorns contained the highest amount of tFAs. Milk and dairy products showed even distribution of tFAS such as C18:1t, C18:2t, and C18:3t. Predominant tFAS isomer of condensed milk and ice cream was C16:1 $\Delta$9t. Frozen french fries and fried chicken contained higher levels of C18:1$\Delta$9t (9.4%), whereas grilled pork (jowl) had no C18:1 $\Delta$9t. The amount of tFAs per serving size was the highest in popcorn, followed by frozen pizza, frozen french fries, fried chicken, and bakeries.

ON EXISTENCE OF SOLUTIONS OF DEGENERATE WAVE EQUATIONS WITH NONLINEAR DAMPING TERMS

  • Park, Jong-Yeoul;Bae, Jeong-Ja
    • Journal of the Korean Mathematical Society
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    • v.35 no.2
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    • pp.465-490
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    • 1998
  • In this paper, we consider the existence and asymptotic behavior of solutions of the following problem: $u_{tt}$ -(t, x) - (∥∇u(t, x)∥(equation omitted) + ∥∇v(t, x) (equation omitted)$^{\gamma}$ $\Delta$u(t, x)+$\delta$$u_{t}$ (t, x)│sup p-1/ $u_{t}$ (t, x) = $\mu$│u(t, x) $^{q-1}$u(t, x), x$\in$$\Omega$, t$\in$[0, T], $v_{tt}$ (t, x) - (∥∇uu(t, x) (equation omitted) + ∥∇v(t, x) (equation omitted)sup ${\gamma}$/ $\Delta$v(t, x)+$\delta$$v_{t}$ (t, x)│sup p-1/ $u_{t}$ (t, x) = $\mu$ u(t, x) $^{q-1}$u(t, x), x$\in$$\Omega$, t$\in$[0, T], u(0, x) = $u_{0}$ (x), $u_{t}$ (0, x) = $u_1$(x), x$\in$$\Omega$, u(0, x) = $v_{0}$ (x), $v_{t}$ (0, x) = $v_1$(x), x$\in$$\Omega$, u│∂$\Omega$=v│∂$\Omega$=0 T > 0, q > 1, p $\geq$1, $\delta$ > 0, $\mu$ $\in$ R, ${\gamma}$ $\geq$ 1 and $\Delta$ is the Laplacian in $R^{N}$.X> N/.

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OSCILLATORY BEHAVIOR AND COMPARISON FOR HIGHER ORDER NONLINEAR DYNAMIC EQUATIONS ON TIME SCALES

  • Sun, Taixiang;Yu, Weiyong;Xi, Hongjian
    • Journal of applied mathematics & informatics
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    • v.30 no.1_2
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    • pp.289-304
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    • 2012
  • In this paper, we study asymptotic behaviour of solutions of the following higher order nonlinear dynamic equations $$S_n^{\Delta}(t,x)+{\delta}p(t)f(x(g(t)))=0$$ and $$S_n^{\Delta}(t,x)+{\delta}p(t)f(x(h(t)))=0$$ on an arbitrary time scale $\mathbb{T}$ with sup $\mathbb{T}={\infty}$, where n is a positive integer, ${\delta}=1$ or -1 and $$S_k(t,x)=\{\array x(t),\;if\;k=0,\\a_k(t)S_{{\kappa}-1}^{\Delta}(t),\;if\;1{\leq}k{\leq}n-1,\\a_n(t)[S_{{\kappa}-1}^{\Delta}(t)]^{\alpha},\;if\;k=n,$$ with ${\alpha}$ being a quotient of two odd positive integers and every $a_k$ ($1{\leq}k{\leq}n$) being positive rd-continuous function. We obtain some sufficient conditions for the equivalence of the oscillation of the above equations.