物联网中几种定位技术应用的比较分析

根据在实际工作中应用物联网中的各种定位技术的开发经验,对目前物联网中定位技术的概念、原理和特点进行了分析和比较,根据这些特点和在实际应用中的测试结果对物联网中这几种定位技术的应用提出建议。     

对公路填石路基施工技术应用的思考

在公路施工过程中,填石路基施工技术是常用的技术之一.在实际工程应用中,需要根据不同公路施工现状、施工技术要点做好填石路基施工技术的合理应用,并且还要对施工中可能出现的问题提前加以预防,如此才能确保施工技术的应用水平.文章对公路填石路基施工技术的应用问题进行了详细分析,以更好地促进该项技术的优化应用.     

等电位连接有效性的检测

根据最新建筑物防雷设计规范,结合工作实际,指出了等电位连接技术在防雷工程中的重要性,等电位连接技术的应用可放宽对接地阻值的要求。重点介绍了如何在工作中检测等电位连接的质量,同时总结了实际应用中存在的主要问题。     

HDPE内衬防腐油管制造技术及应用效益

该文根据向光明所著《HDPE内衬油管的技术特性及应用》,结合我公司在油套管生产线方面的技术积累,及目前延长油矿内衬油管的使用情况;针对内衬油管在应用的经济效益及社会效益进行了分析,对使用过程中解决的实际问题作了阐述。     

无线局域网技术在组建高校信息网中的应用

随着信息化建设的深入和无线网络技术的崛起,无线局域网技术在校园网络建设中的应用越来越广泛。本文首先介绍了无线局域网技术的基本概念,然后根据当前高校的实际情况介绍了无线局域网技术在高校信息网组建中的应用,最后讨论了现阶段无线网络组建及应用中应注意的问题。     

结构损伤诊断技术的研究和发展趋势

综述了近几年来工程结构损伤诊断技术的研究应用，对工程结构损伤诊断的各种方法进行了评述，讨论了各种方法在理论上和实际应用中存在的问题．根据国内外最新文献．推测工程结构损伤诊断的发展趋势。     

300MW大容量燃煤锅炉节能减排技术研究及应用

结合目前我国能源现状和工业锅炉在实际燃烧中对环境的污染,笔者根据工作实际分析了大容量燃煤锅炉存在的问题和原因,在此基础上阐释了改变大容量燃煤锅炉技术应用的措施,并对该技术未来发展做了进一步阐述,供同行参考。     

浅论道路桥梁施工中预应力的应用以及存在的问题

在我国,最初的预应力混凝土结构使用在钢筋混凝土轨枕,因为这样的混凝土结构具有很好的稳定性能。在此之后,预应力混凝土结构在各个项目施工中进行了广泛的应用。随着经济的发展,公路建设的需求增加,公路桥梁工程也越来越多,而预应力混凝土结构技术在桥梁施工中的应用也普遍增加,并根据实际施工情况进行着适当的技术调整,使得预应力技术不断的发展。预应力混凝土结构具有高强度的特性,能够很好的降低混凝土开裂的概率,减轻整个结构的自重,增大桥梁结构的跨度。然而在实际的桥梁施工中,预应力混凝土技术的应用存在着很多问题,本文就对施工过程中常见的问题进行探讨,分析原因并提出相应的处理方法及预防措施。     

VPN技术在实际应用中若干问题的探讨

在虚拟专用网(VPN)的分类和核心技术等方面进行了简要的阐述，并分析和讨论了VPN技术在实际应用中存在的一些问题和问题的解决方法，最后结合实例对VPN技术在实际应用中的实现进行了探讨．     

基于桌面虚拟化的高校机房的调研与构建

该文通过分析现有高校机房在管理和教学方面存在的问题,着重研究将桌面虚拟化技术引入到我校公共机房的管理和维护。通过对比目前主流的虚拟化技术,根据当前我校计算机实验教学环境的特点和机房管理的需求,提出了搭建基于桌面虚拟化架构的高校公共机房的解决方案,在此基础上搭建个性化教学环境进行实际测试和验证,并对测试结果进行了对比分析,指出了今后实际应用管理中应注意的问题。     

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.     

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.     

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the