一类n元轮换不等式的证明

本文对一类n元轮换式V(a_1,…,a_n)=a_3/(a_1+a_2)+…+a_2/(a_n+a_1)构成的不等式V(a_1,…,a_n)=a_3/(a_1+a_2)+…+a_2/(a_n+a_1)≥n/2给出一般性的证明.据此,其它一些类似的轮换不等式可用相同的方法加以证明,从而得到相应的结论.     

多项式根的分布

本文以复变函数论中的 Rouche 定理为基础,给出了有关多项式根的分布规律。Rouche 定理:若 f(Z)与 g(Z)在封闭曲线 C 内及 C 上都解析,又在 C 上有|g(Z)|max{1,(|a_(n-1)| |a_(n-2| … |a_1| |a_0|)/|a_n|}令 f(Z)=a_nZ~n,g(Z)=a_(n-1)Z~(n-1) a_(n-2))Z~(n-2) … a_1Z a_0 由有关 R 的假设可得:|a_(n-1| |a_(n-2| … |a_1| |a_0|<|a_n|R 即(|a_(n-1)| |a_(n-2)| … |a_1| |a_0|)<|a_n|R~n由于 R>1及在 C 上|Z|=R,所以,|a_(n-1)Z~(n-1) a_(n-2)Z~(n-1) …… a_1Z a_0|<|a_nZ~n|也就是说,|g(Z)|<|f(Z)|,因此 f(Z)与 f(Z) g(Z)在 C 内(|Z|相似文献   

关于不定方程a_1X_1+a_2X_2+…+a_nX_n=N的非负解个数的讨论

设不定方程(1)a_1x_1+a_2x_2+…+a_nx_n=N,其中,n≥2,(a_1,…a_n)=1,N和a_i(i=1,2,…,n)均为正整数(且不妨假设a_1≤a_2≤…≤a_n)。 (1) (1)的非负整数解的个数是有限的,设为T_n(N)。记0相似文献   

THE COMPOUND BOUNDARY VALUE PROBLEMS WITH THE MIXED BOUNDARY CONDITIONS IN THE UPPER HALF-PLANE

In this paper, we consider two problems (MR) and (MH).Let L_(1j)(j=1, …, m) be a mutually exclusive closed Lyapunov curve system in the upper half-planeZ~+ and each curve L_(1j) take the clockwise direction as its positive direction, D_(1j)~- be the inner region boundedby L_(2j)(j=1,…,m) and L_1= L_(1j), D_1~+=Z~+\(D_1~- U L_1), X be the real axis, {a_1,b_1…,a_n,b_n} be a set of points on X and -∞相似文献   

几种递推数列通项公式的求法

<正>数列是高中代数的重点内容之一,也是高考考查的重点,从近几年的高考试题看。递推数列为考查热点,通常题目条件中给出a_n,a_(n-1),a_(n-2)及S_n的关系,然后要求解决一些有关数列通项、求和等问题。本文就几种递推数列的通项求法做一些讨论。1递推数列a_(n+1)=pa_n+q型(p,q为常数)通项的求法例1求满足a_1=3,a_(n+1)=1/2a_n+3(n∈N)的数列{a_n}的通项。     

一阶微分方程的几个可积类型-兼谈广义黎卡提微分方程的一个猜想及两个结论

本文拟给出一阶微分方程的几个可积类型。这些方程只要通过适当的变 量变换,就可以化归为变量可分离方程,从而可积。可以着出,通常意义下的 一阶齐次微分方程、线性微分方程,和伯努里(Bernoulli)微分方程,是本文 所给几个可积微分方程的特例。 本文还定义了广义黎卡提方程(Gene rdized Riccati′s eguation): dy/dx+q(X)y=a_0(y)y~n+a_1(X)y~(n-1)+…+a_(n-1)(X)y+a_n(X),(a_0(X)≠0,n≥2):并提出了一个猜想:广义黎卡提方程一般是不能用初等积分法求解的;同时,作者给出了有关广义黎卡提方程的两个结论: (i)在条件a_n(x)≠0,a_(n-1)(X)=c_(n-1) a_(x) (i= l,2,…,n; C_(n-1)为常数)之下,广义黎卡提方程是可积的。 (ii)如果a_(n-1)(X)=0(0≤j(x)=c_(n-i)a_(n-i-1)(x)(i>j+1),则广义黎卡提方程也是可积的。     

关于Frobenius问题

设n≥2,a_1,a_2,…,a_n都是正整数,且(a_1,a_2,…,a_n)=l,记a_1x_1+a_2x_2+…+a_nx_n 当X_i≥0(i=1,2,…,n)时不可表出的最大整数为g(a_1,a_2…,a_n).本文首先用构造性方法简单地证明了g(a_1,a_2,…a_n)的存在性,并运用这种方法给出了某些应用;其次对n=3的重要情形用不同的方法讨论,提出了求g(a_1,a_2,a_3)的一种简便而实用的方法。     

一个关于{1,2,…,n}排列的猜想（英文）

我们证明了孙智伟的下述猜想:对任意不等于3的正整数n,存在{1,2,dos,n)的一个全排列(a_1,…,a_n)使得a_1=1,a_n=n,并且a_1+a_2,a_2+a_3,…,a_(n-1)+a_n,a_n+a_1都与n互素     

关于多项式旣约性问题——教学研究一则

<正> 中学代数中因式分解,一般都是在有理数域Q的范围内考虑的。关于有理系数多项式的既约性有着名的Eisenstein判别法则,现在把它写在下面: 定理1(判别法则): 设 f(x)=a_nX~n+a_(n-1)X~(n-1)+…+a_0 是一个整系数多项式,如果有一个素数p使得     

一个递推数列及勾股连续数

由递推式a_(n+1)=2a_n+a_(n-1) a_0=l,a_1=2,n∈N(l)给出的数列十分有趣,由它可得到勾股为连续自然数的全部基本的勾股数组.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.