受控源的电源性在叠加定理中的表现

本文对电路分析的一些教材中关于受控源在叠加定理中不能参与叠加的观点提出了不同的看法,并通过例题证明受控源也可和独立源一样单独在电路中产生“激励”作用。     

含受控源电路的分析计算方法

利用电压源和电流源的等效变换、叠加定理、戴维南定理等,分析受控源电路时,就不能简单地把它当作独立源来处理。本文就这三种分析方法在含有受控源电路中的应用作一介绍。     

关于补偿定理的推广

本文将通常线性电路分析中的补偿定理推广到含受控源电路,得到统一地处理电路参数(包括独立源、受控源参数以及电阻)改变时,以电流或电压改变量为变量的电路图形,从而直接计算得到变化量。     

含有受控源的线性网络的隐式叠加定理

拓展了叠加定理，指出在具有多个独立源和受控源的线性电路中，任一电压、电流响应可由各独立源和受控源单独作用所得响应分量的合成来得到。文中给出定理的证明。该定理可以视为隐式叠加定理。与原来显式的叠加定理相比较，应用这一定理可以更有效地简化电路计算。     

节点间含源电路的简化分析法

节点分析法是学习分析线性时不变网络以及进行计算机辅助网络分析的基本方法之一。文中将含独立源电路的改进节点分析法，推广到既含独立源又含受控源的电路。计算结果表明，这种方法可以极大地简化含源电路的分析过程。     

泛函随机理论与量子力学（续）

泛函随机理论与量子力学（续）刘涤修（徐州师范大学物理系，徐州，２２１００９）２相互统计独立的随机变量之和的概率函数定理两个相互统计独立的随机变量之和的概率函数等于这两个随机变量的概率函数之积．若Ｘ与Ｙ是两个统计独立的随机变量，则其和ｅ—Ｘ＋Ｙ也是一个...     

受控源及在电路分析中的作用

本文就电路分析课程的教学中,如何引入受控源的概念和受控源在电路分析中的具体地位和作用提出一些看法。     

选加定理中处理受控源的一种新方法

独立电源与受控源在电路中所起的作用不同。在选加定理的使用中,受控源和独立电源的处理方法也不同。独立电源可以单独作用,而受控源不能。本文提出了一种新方法,在选加定理的使用中,受控源也可以象独立电源一样来处理。这种处理方法可简化电路的分析,特别适于电子电路的参数计算。     

节点电压矩阵方程的一种直接列写方法

提出一种直接列写电路节点电压矩阵方程的方法，通过直接建立独立源、受控源和控制变量等向量的ＫＣＬ，ＫＶＬ方程，使节点电压矩阵方程直接写出。该法可适用于含有各类受控源的电路，进行矩阵运算便可得到节点电压解向量和任意输出解向量。     

等效变换在含受控源电路中的应用

当电路中含有受控源时,由于受控源具有受控性和电源性的双重特性,使此种电路的分析、计算过程较麻烦。本文针对不同结构的含线性受控源电路,通过具体实例,采用不同的变换方法介绍了等效变换在含受控源的线性电路中的应用。将受控源电路等效变换成不同的简单电路形式,从而使电路的分析、计算过程大大简化。此方法应用到实际教学中,受到了很好的教学效果。     

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.     

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.     

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-