电能计量装置的误差及更正浅析

分析了电能计量中误差产生的原因,针对不同误差原因提出了更正方法,对电能表本身误差、倍率错误、接线错误情况下的电量更正还有实例进行说明,对于实际运用中用户对电能计量误差的认识、电量追补或退补具有一定的参考价值.     

逆抽样条件下风险差的检验

建立了不同的统计量对逆抽样条件下病例对照组实验中的风险差进行检验.这些统计量分别是Wald统计量,Score统计量和似然比统计量.然后采用Fisher-Score的方法求解感兴趣参数的方差.采用近似的方法计算各统计量条件下犯第1类错误的概率和功效.多数情况下,Score统计量比较好,特别是针对感兴趣的样本量小于30的条件下,Score统计量犯第1类错误的概率能控制在置信水平以下.     

电力计量误差产生的原因与改进措施探讨

针对当前电力计量误差大,无法实现高精度计量问题,开展对电力计量误差产生的原因与改进措施的探讨研究.在明确计量工作重要性的基础上,针对误差产生的具体原因进行分析.通过分析得出,造成电力计量误差产生的主要原因包括:计量装置连线错误、二次压降等.针对存在的两项具体原因,从选择合适精度计量装置和减少电压互感器二次压降两方面,提...     

含有单相380V电焊机负载的用电量计量方式分析

电子式电能表已广泛用于电能的计量,但对于380 V电焊机,由于其接入电压与运行状态的特殊性,当采用不同的计量方式或不同功能的电能表时可能造成电能的错误计量.本文分别用3只220 V电子式单相电能表、1只三相四线电子式电能表、1只三相三线电子式电能表三种计量电焊机用电量的方式进行了分析.     

阐述三相三线电能表错误接线的检测方法

文章主要阐述了电能计量装置中三相三线有功电能表的错误接线检测与分析技术、并分析了错误接线造成的经济损失以及避免错误接线的措施。     

10kV侧计量电压错接在变压器35kV侧的分析

为统一计量装置的规格,二次电压均为100V。在这种情况下容易发生错误接线。而错接线时,表计现场检测很难发现。本文通过举例分析某10kV出线计量装置的电压回路错接在35kV侧二次电压,探讨错误接线的发生原因,这对我们处理日常计量异常情况具有积极的意义。     

石化公司中有功电能表计量损失分析

三相四线三元件电能表在石化企业中的应用也越来越广泛,具有诸多优点,但此类有功电能表仍所存在计量损失等问题。对此,分析了由于电流互感器接线错误而导致的计量损失问题,并通过理论分析,获取了错误情况时的接线和电能的表达式,进一步阐述清楚计量损伤的原因,为解决此类问题提供参考。     

电能计量电压互感器二次侧极性反接的误差分析

在三相三线高压网络中,进行电能计量的电能表必须揍夫电压互感器的三次茸路内。二次线路增多,就大大增加了接线错误的几率。互感器有极性问题,极性反接就是造成计量错误的主要原因之一。三相三线高压乒j络中一般采用三相两元件电能表进行电能计量,配合使用的电压互感器存在两种接线方式,不同的接法造成的误差并不相同,该文简要分析了电压互感器一种正确接线而另一种二次侧反接情况下对电能计量误差的影响,分析了电能表功率表达式、更正系数及更正率。     

浅谈如何搞好变电所电度表的接线工作

指出了电度表计接线的准确是影响电量计量的关键,介绍了几种有功电能计量的接线形式,分析了高压三相两元件有功电度表的错误接线方式。     

三相三线电能表误接线对计量的影响

在新装计量装置中由于电流互感器相序、极性的错误导致电能表的误接线,造成电能计量的不准确。本文列举了几种三相三线电能表常见的误接线,通过向量分析推导出电能表误接线时所反映的有功、无功功率表达式,进而求出其对计量的影响。     

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-