SOURCE CODING THEOREMS FOR GENERAL SEQUENCE MODEL

In this paper, we give a coding theorem for general source sequence. A source sequence \[{\mathcal{T}^{(n)}} = \{ [{X^{(n)}},{p^{(n)}}({X^{(n)}})],[{X^{(n)}} \otimes {Y^{(n)}},{\rho ^{(n)}}({X^{(n)}},{Y^{(n)}})]\} \] is said to be \[({R^{(n)}},{d^{(n)}})\]-compress, if (i)\[{R^{(n)}}\], \[{d^{(n)}}\] are two sequences of real numbers \[{R^{(n)}} \to \infty \]； (ii) there exist \[{\varepsilon ^{(n)}} > 0({\varepsilon ^{(n)}} \to 0)\] and set \[{B^{(n)}} \subset {Y^{(n)}}\] so that \[|{B^{(n)}}| \leqslant {2^{{R^{(n)}}(1 + {\varepsilon ^{(n)}})}}\] and \[{p^{(n)}}{\text{\{ }}({X^{(n)}}){\rho ^{(n)}}({X^{(n)}},{B^{(n)}}) \leqslant {d^{(n)}}\} \geqslant 1 - {\varepsilon ^{(n)}}\] where \[{\rho ^{(n)}}({X^{(n)}},{B^{(n)}}) = \mathop {\min }\limits_{{y^{(n)}} \in {B^{(n}}} {\rho ^{(n)}}({X^{(n)}},{Y^{(n)}})\]. A \[{\mathcal{T}^{(n)}}\] is said to be \[({\mathcal{F}^{(n)}}{D^{(n)}})\]-information bounded, if (i)\[{\mathcal{F}^{(n)}} \to \infty \];(ii) there exist \[{\varepsilon ^{(n)}} > 0\] and conditional probability \[{Q^{(n)}}({Y^{(n)}}/{X^{(n)}})\] so that probability distribution \[{p^{(n)}}({X^{(n)}}{Y^{(n)}}) = {p^{(n)}}({X^{(n)}}){Q^{(n)}}({Y^{(n)}}/{X^{(n)}})\] is satisfied by \[\begin{gathered} {p^{(n)}}\{ ({X^{(n)}},{Y^{(n)}}):i({X^{(n)}},{Y^{(n)}}) \leqslant {\mathcal{F}^{(n)}}(1 + {\varepsilon ^{(n)}}), \hfill \ {\rho ^{(n)}}({X^{(n)}},{Y^{(n)}}) \leqslant {\rho ^{(n)}}\} \geqslant 1 - {\varepsilon ^{(n)}} \hfill \\ \end{gathered} \] where \[i({X^{(n)}},{Y^{(n)}}) = \log \frac{{{p^{(n)}}({X^{(n)}},{Y^{(n)}})}}{{{p^{(n)}}({X^{(n)}}){p^{(n)}}({Y^{(n)}})}}\] Theorem The necessary and sufficient conditions for a source sequence \[{\mathcal{F}^{(n)}}\] to be \[({R^{(n)}},{a^{(n)}})\]-compress is that \[{\mathcal{F}^{(n)}}\] must be \[({R^{(n)}},{a^{(n)}})\]-information bounded. From the theorem we obtain immediately the coding theorem and its converse for stationary and unstationary sources with memory.     

任意六位数的有趣性质——从《为神奇分数m/7增添魅力》中得到的启示

<正>贵刊2013年6月下第20页上洪振铎老师的《为神奇的分数m7增添魅力》一文非常有趣,也很有启发.本文目的是将该文后半部分数字等式,推广成一般等式.在此,与朋友们交流,并请指正.图1性质1已知abcdef是一个六位数,将图1各顶点处的数字按顺时针或逆时针排成数列,其和及平方和都会相等,即(Ⅰ)二位数:ab n+bc n+cd n+de n+ef n+fa n=af n+fe n+ed n+dc n+cb n+ba n.(Ⅱ)三位数:abc n+bcd n+cde n+def n+efa n+fab n=afe n+fed n+edc n+dcb n+cba n+baf n.     

麦比乌斯梯子C(2n,n)的强边色数

本文研究了麦比乌斯梯子C(2n,n)的强边染色问题.利用组合分析的方法,得到了如下结果:当n=3时,χ'_s(C(2n,n))=9;当n=4时,χ'_s(C(2n,n))=10;当n=5,8时,χ'_s(C(2n,n))=8;当n 3且n≡2(mod 4)时,χ'_s(C(2n,n))=6;当n 7且n≡0,1或3(mod 4)时,χ'_s(C(2n,n))=7.     

构造函数解决与自然数有关的问题

解决与自然数有关的命题通常用数学归纳法、二项式定理的展开式 .而数列作为定义在自然数集上的函数 ,若用数学归纳法解题有一定的难度 ,如果将问题转化为函数来处理 ,则往往使问题变得简洁、容易 ,此时常常将 n视为自变量 .下面举几例说明 .例 1　已知 n∈ N ,证明不等式1 12 13 … 1n <2 n .证明　构造函数 f ( n) =1 12 13 … 1n - 2 n ,∵　 f ( n 1 ) - f ( n)　 =1n 1 2 n - 2 n 1　 = n - n 1( n 1 n ) n 1 <0 ,∴　 f ( n 1 ) 相似文献   

证明不等式的几种特殊方法

文[1]给出了六种证明不等式的特殊方法.这里再给出四种,以解决一些不等式的证明问题.1　利用二项式定理证明对于有些不等式,可根据其结构特点,联想或构造二项式模型,利用二项式定理来证.例1　(第2 1届全苏数学竞赛)求证:对于任意的正整数n ,不等式(2n + 1) n ≥(2n) n + (2n - 1) n成立.证　由二项式定理,有　(2n + 1) n- (2n - 1) n=2 [C1n(2n) n -1+C3n(2n) n -3 +…]≥2C1n(2n) n -1=(2n) n,即(2n + 1) n≥(2n) n+ (2n - 1) n.例2　(1988年全国高中数学联赛)已知a ,b为正实数,且1a+ 1b =1.试证对于每一个n∈N都有(a +b) n-an-bn≥2 2n-…     

正整数的一类三分拆的应用

利用正整数n的一类特殊的3分拆n=n1+n2+n3,n1>n2>n3≥1,且n2+n3>n1的Ferrers图将不定方程4x1+3x2+2x3=n(n≥9)的正整数解与这种分拆联系起来,从而得到了该不定方程的正整数解数公式;同时也给出了正整数n的一类4分拆的计数公式.此外,还给出了周长为n的整边三角形的计数公式的一个简单证明.     

关于数论函数方程S(SL(n))=φ(n)的可解性

对于任意正整数n,S(n),SL(n),φ(n)分别为Smarandache函数,Smarandache LCM函数和Euler函数.本文利用S(n),SL(n),φ(n)的基本性质结合初等方法推广了方程S(n)=φ(n)和SL(n)=φ(n),研究了方程S(SL(n))=φ(n)的可解性,给出并证明了该方程仅有正整数解n=1,8,9,12,18.     

双截尾柯西分布顺序统计量的概率性质

设{X_k,1≤k≤n}独立同分布,服从参数为μ,λ;A,B的双截尾柯西分布,X_(1,n),X_(2,n),…,X_(n,n)为其顺序统计量.本文给出X_(k,n)(1≤k≤n)的密度函数,X_(1,n),X_(2,n),…,X_(n,n)的联合密度函数,极端顺序统计量X_(1,n)和X_(n,n)的渐近分布以及X_(k,n)和X_(n-k+1,n)(k1)的渐近分布,并证明X_(1,n)和X_(n,n)是渐近独立的.     

关于n~(1/k)的两个不等式

文 [1 ]中给出了一个涉及n的不等式 :设正整数n >1 ,则2n + 23·n - 2 (n - 1 ) + 23·n - 1≤n <4n + 36 ·n - 4(n - 1 ) + 36 ·n - 1 ( 1 )由不等式 ( 1 ) ,可推出2n + 23·n - 2 - 13≤∑nk=1k≤4n + 36 ·n - 16 ( 2 )当且仅当n =1 ,2时 ,式中等号成立 .本文给出类似于不等式 ( 1 )的关于 kn的两个不等式 ,并提出一个猜想 .定理 1　设正整数n >1 ,则1 2n + 71 6 ·3n - 1 2 (n - 1 ) + 71 6 ·3n - 1 <3n <3n + 24 ·3n - 3(n - 1 ) + 24 ·3n - 1 ( 3)证　要证上限不等式 3n <3n + 24 ·3n- 3(n - 1 ) + 24 ·3n - 1 ,只要证( 3n - 2…     

构造模型求自然数的方幂和

自然数方幂和问题是指Sk(n)=nΣi=1ik(n,k∈N)的计算与表示.早在公元前二百多年,希腊著名科学家阿基米德就已经得出了k=2和k=3时的结果:S2(n)=12+22+…+n2=n(n+1)(2n+1)/6,S3(n)=13+23+…+n3=n2(n+1)2/4,尽管他的证明比较复杂,但S4(n)的结果却始终无法找到,直到一千多年之后的11世纪,阿拉伯数学家才得道:S4(n)=1/30n(n+1)(2n+1)(3n2+3n-1).……     

二次曲面和平面位置关系的判式

在解析几何中有二次曲线与直线位置关系的讨论、二次曲面与直线位置关系的讨论,而二次曲面与平面相关位置关系的探讨较少.本文给出二次曲面a11x2+a22y2+a33z2+2a12xy+2a13xz+2a23yz+2a14x+2a24y+2a34z+a44=0(1)和平面Ax+By+Cz+D=0(2)的相对位置的判别式Δ=a11a12a13a14Aa21a22a23a24Ba31a32a33a34Ca41a42a43a44DA B C D0(aij=aji).(3)并证明了:若Δ>0,则二次曲面(1)与平面(2)相交;若Δ=0,则(1)和(2)相切;若Δ<0,则(1)和(2)相离.     

New parameters of subsets in polynomial association schemes

We define new parameters, a zero interval and a dual zero interval, of subsets in P- or Q-polynomial association schemes. A zero interval of a subset in a P-polynomial association scheme is a successive interval index for which the inner distribution vanishes, and a dual zero interval of a subset in a Q-polynomial association scheme is a successive interval index for which the dual inner distribution vanishes. We derive bounds of the lengths of a zero interval and a dual zero interval using the degree and dual degree respectively, and show that a subset in a P-polynomial association scheme (resp. a Q-polynomial association scheme) having a large length of a zero interval (resp. a dual zero interval) induces a completely regular code (resp. a Q-polynomial association scheme). Moreover, we consider the spherical analogue of a dual zero interval.     

Scalarization of Henig Proper Efficient Points in a Normed Space

In a general normed space equipped with the order induced by a closed convex cone with a base, using a family of continuous monotone Minkowski functionals and a family of continuous norms, we obtain scalar characterizations of Henig proper efficient points of a general set and a bounded set, respectively. Moreover, we give a scalar characterization of a superefficient point of a set in a normed space equipped with the order induced by a closed convex cone with a bounded base.     

Two questions on semi-clean group rings

It was proved in [4] that every group ring of a torsion abelian group over a commutative local ring is a semi-clean ring. It was asked in [4] whether every group ring of a torsion abelian group over a commutative clean ring is a semi-clean ring and whether every group ring of a torsion abelian group over a commutative semi-clean ring is a semi-clean ring. In this paper, we give a positive answer to question 1 and a negative answer to question 2.     

Staircase Parameterization in Dynamical Selection

This paper deals with a variant of a dynamical selection scheme introduced by Attouch and Cominetti for ill-posed convex minimization which combines approximation with the steepest descent method by mean of a suitable parameterization of the approximation parameter as a function of the time. This variant applies to a general inclusion with a maximal monotone operator by mean of a staircase parameterization. A discrete analogue is also considered. Applications to selecting a particular zero of a maximal monotone operator or a particular fixed point of a nonexpansive mapping via regularization techniques are presented. Finally, the alternative use of well-posedness by perturbations is discussed.     

On arithmetic Macaulayfication of Noetherian rings

The Rees algebra is the homogeneous coordinate ring of a blowing-up. The present paper gives a necessary and sufficient condition for a Noetherian local ring to have a Cohen-Macaulay Rees algebra: A Noetherian local ring has a Cohen-Macaulay Rees algebra if and only if it is unmixed and all the formal fibers of it are Cohen-Macaulay. As a consequence of it, we characterize a homomorphic image of a Cohen-Macaulay local ring. For non-local rings, this paper gives only a sufficient condition. By using it, however, we obtain the affirmative answer to Sharp's conjecture. That is, a Noetherian ring having a dualizing complex is a homomorphic image of a finite-dimensional Gorenstein ring.

     

Spectrum of a homogeneous graph

We describe the spectrum of the Laplacian for a homogeneous graph acted on by a discrete group. This follows from a more general result which describes the spectrum of a convolution operator on a homogeneous space of a locally compact group. We also prove a version of Harnack inequality for a Schrödinger operator on an invariant homogeneous graph.     

Partially isometric dilations of noncommuting -tuples of operators

Given a row contraction of operators on a Hilbert space and a family of projections on the space that stabilizes the operators, we show there is a unique minimal joint dilation to a row contraction of partial isometries that satisfy natural relations. For a fixed row contraction the set of all dilations forms a partially ordered set with a largest and smallest element. A key technical device in our analysis is a connection with directed graphs. We use a Wold decomposition for partial isometries to describe the models for these dilations, and we discuss how the basic properties of a dilation depend on the row contraction.

     

Inventory replenishment model: lot sizing versus just-in-time delivery

Motivated by a practical industrial problem where a manufacturer stipulates a minimum order from each buyer but where a local dealer promises the buyer a just-in-time delivery with a slightly higher unit cost, this paper uses a dynamic lot-sizing model with a stepwise cargo cost function and a minimum order amount constraint to help the buyer select the supplier with minimum total cost.     

A pair of orthogonal frames

We start with a characterization of a pair of frames to be orthogonal in a shift-invariant space and then give a simple construction of a pair of orthogonal shift-invariant frames. This is applied to obtain a construction of a pair of Gabor orthogonal frames as an example. This is also developed further to obtain constructions of a pair of orthogonal wavelet frames.