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1.
将血浆中PaCO2作为自变量、△[HCO3-]/△PaCO2作为因变量,对慢性呼吸性酸碱平衡紊乱时,肾的代偿调节作用进行了量化处理.根据两者间的量化关系,看到:慢性呼吸性酸中毒时,随着血浆中PaCO2值越来越大,△[HCO3-]/△PaCO2的变化率越来越小;慢性呼吸性碱中毒时,随着血浆中PaCO2值越来越小,△[HCO3-]/△PaCO2的变化率也越来越小.这些结果完全符合生物学规律.提示这一量化处理对研究慢性呼吸性酸碱平衡紊乱时,肾代偿调节机制、代偿强度等有一定的意义.  相似文献   

2.
关于酸、碱平衡调节中肺作用的数学描述   总被引:2,自引:2,他引:0  
在正常或疾病情况下,人体内酸碱平衡的调节是一个颇为复杂的过程.迄今尚存很多争议性问题,近年国外多倾向于建立各种数学模型,以期揭示体内酸碱平衡的调节机制.本文将“顺应性”这一概念,引入到人体酸碱平衡调节的研究中,并观察了在代谢性酸中毒和代谢性碱中毒时,肺参与代偿调节的顺应性变化范围和变化幅度,为应用数学模型进一步深入探讨机体内复杂的酸碱平衡调节机制,提供新的研究途径和手段.  相似文献   

3.
在慢性呼吸性酸碱平衡紊乱研究中,引入一新的概念,即顺应性C=Δ[HCO_3-]/ΔPaCO_2,它的变化范围大小能够描述肾调节能力的大小.为了将肾调节能力进行了量化,以X=PaCO_2为自变量,Y=C=Δ[HCO_3-]/ΔPaCO_2,它的变化范围大小能够描述肾调节能力的大小.为了将肾调节能力进行了量化,以X=PaCO_2为自变量,Y=C=Δ[HCO_3-]/ΔPaCO_2为因变量,分别绘制出顺应性C=Δ[HCO_3-]/ΔPaCO_2为因变量,分别绘制出顺应性C=Δ[HCO_3-]/ΔPaCO_2范围中左端点和右端点的散点图,并求出其拟合曲线方程及其变化率,这种定量方法为进一步深入研究肾的调节能力提供依据.  相似文献   

4.
文[1]给出了三角形重心的两个性质,文[2]给出了三角形旁心的两个性质,文[3]给出了三角形外心的两个性质.读后深受启发,笔者对文[1][2][3]做了进一步的研究,得到了三角形两个统一的向量性质.性质1 经过△ABC所在平面上的一点O(不在顶点A上),任作一直线l,分别交边AB,AC所在直线于M,N两点,且→=m→(AB),→(AN)=n→(AC),用SA、SB、Sc、S分别表示△OBC、△OAC、△OAB,△ABC的面积(下文同),则(1)当点O落在区域①②时,有SB/m+SC/n=S.(2)当点O落在区域③时,有SB/m+SC/n=-S.(3)当点O落在区域④⑦时,有SB/m-SC/n=-S.(4)当点O落在区域⑤⑥时,有SB/m-SC/n=S.  相似文献   

5.
格值模型论中的省略型定理   总被引:6,自引:2,他引:4  
王世强 《数学学报》1982,25(2):202-207
<正> 我们在[2][3]开始的工作中,对于多值模型论准备作一些初步考查.我们已经讨论了2-值模型论中超积基本定理及紧致性定理在多值时的初步推广.本文是这一工作的继续,我们将证明某些值格时的省略型定理.文中有些概念及记号可参看[2]、[3]、[4](但本文的内容与[2]、[3]无关).以下再补充叙述一些与本文有关的概念.  相似文献   

6.
严加安 《数学学报》1980,23(2):293-300
设 X 为一零初值局部鞅,(?)(X)为方程(?)的唯一解.本文证明了:(1)设△X≥0.如果对一切0δ>0,及K>2/δ~2(2-(δ)),使得△X≥-1+δ,且 E[expK[X,X]_∞]<∞,则(?)(X)为 L(?)可积鞅,其中r=2δ(2-δ)K/2+δ(2-δ)~2K(1相似文献   

7.
<正>1原题呈现如图1,矩形ABCD的边AB上有一点E,边AD上有一点F,△CEF是正三角形.猜想S△AEF,S△BCE,和S△CDF的关系,并加以证明.对初中生而言,给出猜想S△AEF=S△BCE+S△CDF容易,但证明猜想有一定难度,且证法的选择非常关键.文[1]、文[2]和文[3]从不同的角度用不同的方法证明了猜想,殊途同归,各有所长.其中文[3]用“图形对称”破解问题,若用“图形旋转”来证明猜想,则会得到不一样的思维体验与感悟.  相似文献   

8.
赖绍永  周盛凡 《数学进展》2000,29(5):417-420
Gaustavo Ponce与Thomas C.Sideris猜测:对一些具有特殊非线性项的半线性波动方程,如utt-△u=u^k(Du)^αx∈R^n,k∈Z^ ,ρ=│α│≥2,其中Sobloev指数会在[n/2,n/2 1]中,他们在x∈R^3时回答了这一问题,本文在R^n(n≥4)中得到了半线性波动方程utt-△u=u^k(Du)^α(x∈R^n,k∈R^n,k∈Z^ ,p=│α│≥2)的Sobolev指数为max{n/2,(n/2-1)1-3/l-1 2},此数确实在区间[n/2,n/2 1]中,特别当ρ≤n-1时,我们得到了此半线性波动方程的Sobolev指数为n/2。  相似文献   

9.
文 [1 ]已证明 :在任意△ ABC中 ,有cos3 A cos3 B cos3 C≥ 38,其中“=”当且仅当△ ABC为正三角形时成立 ,并给出如下猜想 :cosn A cosn B cosn C≥ 3( 12 ) n,( n≥ 2 ,n∈ N) .文 [2 ]利用著名的 Jacobsthal不等式证明了这个猜想 ,下面利用平均值不等式给这个猜想一个简捷证明 .猜想证明 :当 n =2时不等式易证 (略 ) .当 n >2时 ,对非钝角△ ABC,由平均值不等式知 :2 ( 2 cos A) n n - 2≥ 4 n .cos2 A,即  ( 2 cos A) n≥ 2 n( cos2 A - 14 ) 1 ,同理  ( 2 cos B) n ≥ 2 n( cos2 B - 14 ) 1 ,  ( 2 cos C)…  相似文献   

10.
Let■=-△+V be a Schrdinger operator on R~n,n3,where △is the Laplacian on R~n and V≠0 is a nonnegative function satisfying the reverse Holder's inequality.Let[b,T]be the commutator generated by the Campanatotype function b∈■ and the Riesz transform associated with Schrdinger operator T=▽(-△+V)~(-1/2).In the paper,we establish the boundedness of[b,T]on Lebesgue spaces and Campanato-type spaces.  相似文献   

11.
Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.  相似文献   

12.
最大度不小于5的外平面图的邻强边染色   总被引:5,自引:0,他引:5  
图G(V,E)的一k-正常边染色叫做k-邻强边染色当且仅当对任意uv∈E(G)有,f[u]≠f[v],其中f[u]={f(uw)|uw∈E(G)},f(uw)表示边uw的染色.并且x'as(G)=min{k|存在k-图G的邻强边染色}叫做图G的图的邻强边色数.本文证明了对最大度不小于5的外平面图有△≤x'as(G)≤△ 1,且x'as(G)=△ 1当且仅当存在相邻的最大度点.  相似文献   

13.
田谷基 《数学杂志》2004,24(4):355-360
本文讨论拟微分算子象证的Witt乘积与C[x]▲△A.G[p]的乘积之间的关系,得到以下结果:具有Witt乘积的象证类S1.0^m。是具有普通乘积的函数类S1.0^m经过对Hopf代数的乘积量子化得到的,进一步,给出了C[x]▲△h.cC[p]上标准的辫导数的显示表示,并且证明了其上的Poisson括号与经典的具有同一形式.  相似文献   

14.
在万有Teichmller空间的对数导数嵌入模型T1(△)中,我们证明了存在无穷多个点[h]∈LT1(△),h(△)相互不Mbius等价,它们到边界的距离均为1,而在万有Teichmller空间的Schwarz导数嵌入模型T(△)中,只有一个点Sid具有类似性质.论文还得到了万有Teichmller空间两类嵌入模型的测地线的一些新的性质.  相似文献   

15.
This paper gives an extension of previous work [2] on weakly nonlinear shallow water waves over a variable bottom to include the effects of strong bores and small surface disturbances. We first consider the interaction of a strong bore with quiescent water over an isolated bottom disturbance to highlight some of the modifications that are introduced in our results for both noncritical and transcritical Froude numbers. We also exhibit the secular effect on the bore trajectory of a bottom disturbance that has a nonzero average. In a second example, we consider the interaction of a strong bore with a small amplitude periodic surface disturbance upstream. We show that downstream of the bore, the wave length of this disturbance increases, whereas its amplitude increases (decreases) depending on whether the bore speed is larger (smaller) than a critical value. We also use this example to illustrate the derivation of the solution and bore trajectory to second order accuracy. All our asymptotic results, obtained in the form of multiple scale expansions, are compared with numerical solutions for a number of illustrative cases.  相似文献   

16.
In this study a theoretical approach is pursued to investigate the effects of suction and blowing on the structure of the lower branch neutral stability modes of three-dimensional small disturbances imposed on the incompressible von Karman’s boundary layer flow induced by a rotating-disk. Particular interest is placed upon the short-wavelength, non-linear and nonstationary crossflow vortex modes developing within the presence of suction/blowing at sufficiently high Reynolds numbers with reasonably small scaled frequencies. Following closely the asymptotic framework introduced in [1], the role of suction on the non-linear disturbances of the lower branch described first in [2] for the stationary modes only, is extended in order to obtain an understanding of the behavior of non-stationary perturbations. The analysis using the rational asymptotic technique based on the triple-deck theory enables us to derive initially an eigenrelation which describes the evolution of linear modes. The asymptotic linear modes calculated at high Reynolds number limit are found to be destabilizing as far as the non-parallelism accounted by the approach is concerned, and they compare fairly well with the numerical results generated directly by solving the linearized system with the usual parallel flow approximation. An amplitude equation is derived next to account for the effects of non-linearity. Even though the form of this equation is the same as that of found in [2] for no suction, it is under the strong influence of suction and blowing. This amplitude equation is shown to be adjusted by a balance between viscous and Coriolis forces, and it describes the evolution of not only the stationary but also the non-stationary modes for both suction and injection applied at the disk surface. A close investigation of the amplitude equation shows that the non-linearity is highly destabilizing for both positive and negative frequency waves, though finite amplitude growth of a disturbance having positive frequency close to the neutral location is more effective at destabilization of the flow under consideration. Finally, a smaller initial amplitude of a disturbance is found to be sufficient for the non-linear amplification of the modes in the case of suction, whereas a larger amplitude is required if injection is active on the surface of the disk.  相似文献   

17.
文[1]曾用"四轴概念"进行分析.并得出了平面曲轴八缸V型内燃机二阶往复惯性力的平衡方案:文[2]又迂回地从前案简化出"二轴平衡"规则.本文系用"二轴概念"直接推出了跟文[2]完全符合"异途同归"的结果,并提出了"滑块平衡"方案.作为一个侧重于数学的附带收获,我们可能发现了一个新型曲线,被命名为"奇形四叶玫瑰花曲线".  相似文献   

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