次Hermite矩阵的次正定性

若ｎ阶次Ｈｅｒｍｉｔｅ矩阵Ａ，对任意非零向量Ｘ＇＝（ｘ＿１，ｘ＿２，…ｘ＿ｎ）∈Ｒ￣ｎ，有ＡＸ＞０，则称次Ｈｅｒｍｉｔｅ矩阵Ａ是次正定的．给出了判定次Ｈｅｒｍｉｔｅ矩阵次正定的几个充要条件：定理ｎ阶次Ｈｅｒｍｉｔｅ矩阵Ａ是次正定的，当且仅当下列条件之一成立：（ｌ）Ｈｅｒｍｉｔｅ矩阵ＪＡ是正定的；（２）存在ｎ阶可逆复矩阵Ｐ，使ＡＰ＝Ｊ；（３）次Ｈｅｒｍｉｔｅ矩阵Ａ的４ｋ阶，４ｋ十互阶下次主子式为正，４ｋ＋２阶，４ｋ＋３阶下次主子式为负；（４）存在ｎ阶可逆复矩阵Ｐ，使其中λ＿ｉ＞０，ｉ＝１，２，…，ｎ。     

关于矩阵迹的几个不等式

设Γ＿１为对角线元素按减序排列的非负对角形矩阵，Ｕ＿１是酉矩阵，ｉ＝１，２，…，ｍ，则有当Ａ＿１，Ａ＿２．…，Ａ＿ｍ为半正定Ｈｅｒｍｉｔｅ矩阵时，有其中Γ＿１＝ｄｉａｇ（σ＿１（Ａ＿１），σ＿２（Ａ＿ｉ）．……σ．（Ａ＿ｉ））．ｉ＝１，２．…，ｍ。     

A′da′m循环图

若对任意的与ｎ互素的整数λ，都有〈λｊ＿１，λｊ＿ｒ，…，λｊ＿ｒ〉＝〈ｊ＿１，ｊ＿２，…，λ＿ｒ〉，则称循环图Ｃ＿ｎ〈ｊ＿１，ｊ＿２，…，ｊ＿ｒ〉为Ａ′ｄａ′ｍ循环图。本文给出了一个循环图Ｃ＿ｎ〈ｊ＿１，ｊ＿２，…ｊ＿ｅ〉为Ａ′ｄａ′ｍ循环图的充要条件以及ｎ阶Ａ′ｄａ′ｍ循环图的个数的计算公式。     

关于图B（m,n）的优美性

证明了：当ｍ≡１或２（ｍｏｄ４）时，Ｂ（ｍ，ｎ）＝Ｃ＿ｍ∪Ｐ＿ｎ是优美图，其中Ｃ＿ｍ＝Ａ＿１Ａ＿２…Ａ＿ｍＡ＿１，Ｐ＿ｎ＝Ａ＿１Ｂ＿１Ｂ＿２…Ｂ＿ｎ（ｍ≥３，ｎ＞０）。     

矩阵的一个定理和线性方程组解的结构

设Ａ∈Ｍ＿（ｍ×ｎ）（Ｆ），则存在ｍ阶可逆矩阵Ｐ和ｎ阶可逆矩阵Ｑ，使其中ｒ＝Ｒ（Ａ）；本文还讨论了一般线性方程组Ａ＿（ｍｎ）Ｘ＿（ｎ１）＝ｂ＿（ｍ１）的可解性及解的结构与矩阵Ｐ，Ｑ之间的关系。     

一道数学竞赛题的推广

记Ｂ是由１，２，…，ｎ的循环排列组成的集合，Ａ＿３（ｎ）＝ｍａｘｍｉｎ（ａ＿（ｉ＋１）＋ａ＿（ｉ＋２）＋ａ＿（ｉ＋３）），其中ｉ＝０，１，２，…．ｎ－１，ａ＿（ｎ＋１）＝ａ＿１，ａ＿（ｎ＋２）＝ａ＿２；ａｉ取１．２，…，ｎ中的任意值，ｉ＝１，２，…，ｎ．本文讨论了Ａ＿３（ｎ）的上界：除ｎ＝３，５．６外，当３｜ｎ－１时，Ａ３（ｎ）≤　；当３｜ｎ时，Ａ３（ｎ）≤　；当３｜ｎ＋１时．Ａ＿３（ｎ）≤．     

分块矩阵的初等变换和合同变换

分块矩阵的初等变换和合同变换江佑民（抚州师专数学系）投Ａ是数域Ｆ上，ｎ×ｎ的矩阵，将Ａ分成分块矩阵，并设Ａ的行的分法与列的分法一致，其中，Ａ＿（ｉｊ）为Ｆ上，ｎ＿ｉ×ｎ＿ｊ矩阵，ｎ＿１＋ｎ＿２十…＋ｎ＿ｓ＝ｎ。定义下面的变换称为分块矩阵的初等变换。１...     

n维Oppenheim不等式及其应用

设ａ＿ｉ（ｉ＝１，２，３）为三角形ΔＡ＿１Ａ＿２Ａ＿３的边长，Ｓ为ΔＡ＿１Ａ＿２Ａ＿３的面积，λ＿ｊ（ｊ＝１，２，３）为任一组正数．作者将Ｏｐｌｓｏｎｂｅｉｍ三角形不等式推广到ｎ维欧氏空间Ｅ￣ｎ中的ｎ维单形，从而获得了ｎ维单形的Ｏｐｐｅｎｂｅｉｍ不等式这里Ｖ是ｎ维单形Ａ＿１Ａ＿２…Ａ＿（ｎ＋１）的体积，Ｖ＿ｉ为顶点Ａ＿ｉ所对之侧面的面积，λ＿ｉ为任意一组正数．     

圈Cn的道路多项式

道路多项式Ｐ＿ｋ（λ）是上，下对角线元素为１，其余位置元素为０的ｋ阶方阵的特征多项式，ｋ≥１和Ｐ＿０（λ）＝１。若Ｐ＿ｋ（Ａ）≥０，ｋ＝０，１，２，…，则说ｎ阶方阵Ａ是道路正矩阵。当图的邻接矩阵是道路正矩阵时，则称这个图是道路正图。该文给出了圈Ｃ＿ｎ的邻接矩阵的道路多项式计算公式。证明它是道路正图。     

实对称矩阵逆特征值问题的可解条件

该文考察以下２个逆特征值问题（１）问题（ＳＡ）；设Ａ＝（ａｉｊ）为ｎ阶实对称矩阵，其主对角元ａｉｊ＝０，ｉ＝２，．．．．ｎ，给定时角矩阵Ａ＝ｄｉａｇ（λ１，λ２，．．．．λｎ）∈Ｒ＾ｎ×ｎ，求一实时对角矩阵Ｘ＝ｄｉａｇ（ｘ１，ｘ２，．．．．ｘｎ）∈Ｒ＾ｎ×ｎ，使λ（Ａ＋Ｘ）＝λ（Ａ），（Ⅱ）问题（ＳＭ）：设Ａ（ａｉｊ）为ｎ阶实时对称矩阵，其主对角元ａｉｊ＝１，ｉ＝１，２，．．．．ｎ。给定对角矩阵Ａ     

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.     

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.     

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.     

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.     

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。     

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.     

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.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-