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31.
本文从平板扫描仪的结构和信息捕获特点分析灰色再现误差的原因。两种平板扫描仪的灰色再现测量数据表明,中性灰捕获后灰度等级按红、绿、蓝次序升高,总体上EpsonGTX970的灰色再现精度要高于SeanMaker3850Ⅲ扫描仪。  相似文献   
32.
The asymptotic stability of linear neutral systems with a single delay is investigated in this article. Based on the characteristic equation, new algebraic criteria for the stability of the system are derived in terms of the spectral radius of corresponding modulus matrices. The significance of our new criteria is that it takes into consideration the structure information of the system matrices, thus reducing the conservatism found in the literature. Numerical examples are given to demonstrate the new stability criteria and to compare them with the previous results in the literature.  相似文献   
33.
文中研究了一类具有连续变量的二阶中立型多时滞差分方程,给出了该类方程所有有界解解振动的几个充分条件.  相似文献   
34.
The problem of asymptotic stability of linear neutral systems with multiple delays is addressed in this article. Using the characteristic equation approach, new delay-independent stability criteria are derived in terms of the spectral radius of modulus matrices. The structure information of the system matrices are taken into consideration in the proposed stability criteria, thus the conservatism found in the literature can be significantly reduced. Simple examples are given to demonstrate the validity of the criteria proposed and to compare them with the existing ones.  相似文献   
35.
This paper is a further note which corrects an error of the paper by Park and Won. A new stability criteria which is less conservative than those in the literature is presented.  相似文献   
36.
目的:研究高温α-淀粉酶处理浓度和时间对中性洗涤纤维(NDF)的影响,为准确测定NDF提供参考。方法:利用玉米、豆粕、玉米秸秆和黄豆秸秆为原料,开展5批试验,每批5个处理,每个处理3个重复。在每批试验中,分别用0、0.5、1.0、1.5和2.0 g/L高温α-淀粉酶对其在75℃处理24 h,研究高温α-淀粉酶的浓度对淀粉消失率和NDF测定结果的影响;用2.0 g/L高温α-淀粉酶在75℃对饲料原料分别处理0、12、24、36和48 h,研究高温α-淀粉酶的处理时间对淀粉消失率和NDF测定结果的影响。结果:随着高温α-淀粉酶的浓度升高,玉米、玉米秸秆和黄豆秸秆的淀粉消失率分别线性提高(P0.05),但对豆粕的淀粉消失率影响较小(P=0.401)。玉米和豆粕的NDF测定结果分别线性降低(P0.05),但对玉米秸秆(P=0.300)和黄豆秸秆(P=0.144)的NDF测定结果影响较小。随着高温α-淀粉酶处理时间的增加,玉米、豆粕、玉米秸秆和黄豆秸秆的淀粉消失率分别线性提高(P0.05)。与对照组相比,玉米、豆粕、玉米秸秆和黄豆秸秆的NDF分别线性降低(P0.05)。结论:添加高温α-淀粉酶能够有效降低饲料原料中淀粉含量,淀粉酶添加量越大或处理时间越长,对淀粉含量降低效果越明显,饲料原料的NDF测定结果就越准确。在本试验中,用于测定饲料原料的适宜α-淀粉酶的浓度与时间分别为2.0 g/L与24 h。  相似文献   
37.
By means of Mawhin's continuation theorem, we study a kind of fourth-order p-Laplacian neutral functional differential equation with a deviating argument in the form:
(φp(x(t)−cx(tδ)))=f(x(t))x(t)+g(t,x(tτ(t,|x|)))+e(t).  相似文献   
38.
The objective of the present study was to evaluate hypolipidemic effect of methanolic extract of Celastrus paniculatus in experimentally induced hypercholesterolemic rats. Hypercholesterolemia was induced by feeding the animals with high fat diet. Oral administration of methanolic seed extract (50%) of Celastrus paniculatus at the optimized dose of 65 mg/kg body weight, substantially reduced the plasma total cholesterol, triglycerides and LDL cholesterol in comparison with induced hypercholesterolemic animal group and the results were comparable with the standard hypocholesterolemic drug and almost similar to the control group. Atherogenic index and liver weight of treated animals also showed significant decrease compared to the hypercholesterolemic animals. It substantially increased the HDL cholesterol level as compared to control group. A significant increase in the activities of lipoprotein lipase and plasma LCAT enhanced hepatic bile acid synthesis and thereby, increased degradation of cholesterol to neutral sterols. Furthermore, the activities of HMG-CoA reductase, glucose 6-phosphate dehydrogenase and malate dehydrogenase were significantly reduced. Histological studies showed less cholesterol deposits in the aorta of animals fed with seed extract of C. paniculatus compared to the induced hypercholesterolemic animals not given C. paniculatus supplement.  相似文献   
39.
研究了一类具变滞量的变系数的二阶中立型差分方程的振动性,给出了该类方程振动及差分算子△振动的充分条件  相似文献   
40.
《苏日中立条约》与中国   总被引:2,自引:0,他引:2  
《苏日中立条约》的签订作为二战期间苏日关系和国际关系中的一个重大事件,使苏日双方得以避免两线作战。但从苏日双方签约的动机、谈判的中心议题乃至条约的内容看,都是围绕着中国问题而展开的。《苏日中立条约》是日苏双方牺牲中国利益、干涉中国主权而达成的交易,而且条约的签订对中国的抗日战争和远东国际关系格局的变动,乃至第二次世界大战的进程都产生了重大而深远的影响。  相似文献   
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