关于周期函数的两个定理

本文绘出两个定理，为判断一元函数的周期性提供了方便。定理1若函数y＝f（x）在R上的图象关于直线x＝a与x＝b（a＜b）对称，则函数f（x）是周期函数。定理2若函数y＝f(x)在R上的图象关于点A（a，y0）和直线x=b（a相似文献   

6-连通图最长圈上的可收缩边

 图的可收缩边与可去边是研究连通图的构造和使用归纳法证明连通图一些性质的有力工具。设G是一个6-连通图,e∈E（G）,若收缩e后得到的图仍是6-连通的,则称e是G的可收缩边。采用树型结构理论进行分类讨论,得到如下结论：① 如果P:x=x1x2…xn=y是6-连通图G的一条最长（x,y）－路,xi xi+1是一条不可收缩边,且S={xi,xi+1,u1,u2,u3,u4}是其对应的6-点割,则G-S的每一个断片至少包含P上的一个点;② 设P:x=x1x2…xn=y是6-连通图G的一条最长（x,y）－路,且G的任意断片的阶都大于2。如果P上任意顶点xi都满足条件d（xi）≥7或者若d（xi）=6则[V（P）]中无3-圈包含它,那么P上至少包含一条可收缩边。在上述结论的基础上,进一步研究了任意断片阶都大于2的6-连通图中最长圈上的可收缩边的分布情况,得到如下新结果：任意断片阶都大于2的6-连通图最长圈上至少有两条可收缩边。     

Series-Parallel图的全选择数与全色数

对2-连通Series-Parallel图G，证明了当△（G）≥4时，其全选择数等于△（G） 1；在△（G）≥3时，其全色数等于△（G） 1；对△（G）≠时，其边选择数等于其边色数（即列表染色猜想）。由于外平面图是特殊的Series-Parallel图，本文包含了外平面图的相应染色结论。     

关于奇完全数的存在问题

如果正整数n适合δ（n）＝2n，则称n是完全数。w（n）是n的不同素因数的个数。本文证明了：如果n为奇数且w（n）2，则n不是完全数；如果正奇数n有标准分解式，其中p1、p2、…、ps是适合p1＜p2＜…＜ps的素数，a1、a2、…、as是正整数，则当a1＝1时，n不是完全数。     

互为反函数的函数值间的关系

高中代数上册中定理：“函数y二人x）的图象和它的反函数x二人Z的图象关于直线x一X对称。”指出了互为反函数的函数图象间的关系。由该定理的证明过程不难发现；若点八。。；在函数y一f（）的图象上，则点M；。，。；在它的反函数x一人Z的图象上；反之亦然。由此可以得到函数y一八l）在某点的函数值与它的反函数y一兀在相应处的函数值之间的关系。即：命题：函数y一八x）有反函数y一九，（l）若f（）一b，则几Z—a；（2）著人Z一a，则f（）一b。充分利用互为反函数的函数值间的关系，可以使某些问题得到十分简捷的解决。例1设八x）一4”…     

关于丢番图方程x8+py2=4z4与x4+16py8=z2

设p为奇数，证明了丢番图方程x^8＋py^2=4z^4（x，y）；1除开p=3时仅有正整数解（z，y，z）=（1，1，1）和p=7时仅有正整数解（x，y，z）=（1，3，2）之外，无其它正整数解。证明了方程x^4＋16py^8=z^2，p≡3（mod 4），2/z，（x，y）=1，无正整数解。证明了P≡3（mod 4），方程x^4＋16py^8=z^2，（x，y）=1当2/x时，除开p=3时仅有正整数解（x，y，z）-（1，1，7）外，无其它正整数解；当2｜x时，有解x^2=2｜pr^8-s^8｜，y=rs，z=2（pr^8＋s^8），2/rs，（r，s）=1。从而推广了文[4]的结果。由此可知（x，y，z）=（2，1，8）是方程x^4＋48y^8=z^2的一个本原解，文[4]漏掉了此解，这说明文[4]引理2不是完全正确的，依据引理2证明的结论也是不可靠的。     

六角系统的点强全色数

对图G及正整数k,映射σ：VUE→{1,2,…,k}满足：（1）任意e1,e2∈VUE,如果e1,e2是相邻或相关联的,则有σ（e1）≠σ（e2）;（2）对u,v,w∈V（G）,uw,vw∈E（G）,uv￠E（G）有σ（u）≠σ（v）,则称σ为G的一个k-点强全染色,并且xτ^vs（G）={k｜存在G的k点强全染色},称为G的点强全色数．研究了六色系统图G的点强全色数,得到△（G）＋l≤xτ^vs;（G）≤△（G）＋2,其中△（G）,xτ^vs（G）分别表示G的最大度和点强全色数．     

与任意图2-正交的(g,f)-因子分解

设G是一个图，用V(G）和E(G）表示它的顶点集和边集，并设g(x）和f(x）是定义在V(G）上的两个整数值函数，且对每个x∈V(G），有4≤g(x)≤f(x)，则图G的一个支撑子图F称为G的一个（g，f）-因子，如果对每个x∈V(G)，有g(x)≤dF(x)≤f(x)。图G的（g，f）-因子分解是指E(G）能划分成边不交的（g，f）-因子，设F={F1,F2,…,Fm}和H分别是图G的因子分解和子图，若对所有1≤i≤m有|E(H)∩E(Fi）|=2，则称F和H2-正交。本文证明：若G是一个（mg m-1，mf-m 1）-图，H是G中任一有2m条边的子图，则G有一个（g，f）-因子分解与H2-正交。     

序与“复数无大小”

在数系中，自然数、整数、有理数、实数均有大小，且能排次序。复数能否排次序？为什么复数没有大小？下面从现代数学的基础结构之———序结构的观点探讨一下复数元大小的根源，并对中学复数教学相关的问题谈一点看法。1集的序关系实数集中，有小于“＜”、等于“。”、大于“＞”3种关系。另外，近代数学中还常用＜表示“小于或等于”，即“＜”相当于“＜”。定义1如果在集M的元素之间定义一个关系“＜”，满足：（1）三分律若x、yeM，则x＜y，但x4y；x＝y；x＞y，但y4y三者有且只有一种成立。（2）传递性若X，y，XEM，X＜y，且y＜Z…     

平面三角剖分图的L(2,1)标号

图G的L（2，1）标号是从一个顶点集V（G）到非负整数集的函数f(x)，使得若d(x,y)＝１，则|f(x)-f(y)|≥２；若d(x,y)=2，则|f(x)-f(y)|≥1。图G的L（2，1）标号数λ（G）是使得G有max{f(v):v∈V（G）}=k的L（2，1）标号中的最小数k。本文证明了对最大度数为△的一般平面三角剖分图G，有λ（G）≤△^2-△；当G的直径大于2时，有λ（G）≤△^2-△。     

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.     

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.     

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.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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.