基于电阻应变片式传感器的单体液压支柱密封检测系统

介绍了一种单体液压支柱密封检测系统，可对单体液压支柱做高、低压密封试验，系统前端检测元件采用电阻应变片式传感器。阐述了系统的设计方法和技术特点，指出该系统可提高煤矿单体液压支柱密封检测工作的自动化水平，具有很好的应用前景。     

液压系统中的几种密封模式研究

按照密封机理和密封结构分析，液压系统中的密封有被动密封、主动密封和隔离密封等。文中对这几种密封模式进行分析，对密封件和密封结构的设计具有一定的指导作用。     

基于径向自紧密封的双金属复合管液压成形

针对现有复合管制造中存在的问题，开发了一种径向自紧密封式双金属复合管液压胀合成形装置，介绍了该装置的工作原理及技术特点，阐述了复合管液压成形过程的原理，并采用弹塑性理论分析了其在液压成形过程中内管及外管的应力应变状态．利用变形协调条件，得出了成形压力与复合管内外管之间残余接触压力的理论计算公式，并通过实验对公式进行了验证．结果表明，该新技术性能可靠且可适于工程应用．     

高炉炉顶液压控制系统改进与应用

本文主要介绍对高炉炉顸液压控制系统存在的设计不合理，稳定性差等问题，进行的一系列改造和实验，使液压控制系统得到稳定顺行，满足生产要求。     

充压密封机理的研究

本文介绍了充压密封的密封作用原理，根据单体液压支柱的工作特性曲线，计算出了充压密封的泄漏流量值；通过对充压密封的密封摩擦阻力分析，为充压密封圈的设计提供了科学依据。图４，参３。     

硫化机高压柱塞油缸密封问题的研究

在液压传动中，柱塞与缸体的配合一般采用（Ｄ４／Ｄｃ４）Ｈ８／Ｆ９的间隙配合。但对大直径的液压缸来讲，其产生的间隙便会增加，导致严重泄漏，即影响硫化机的性能，又浪费液压油，本工作结合生产实际从理论上讨论了液压介质泄漏量Ｑ与间隙δ以及压力Ｐ之间的关系；分析了Ｖ型密封圈在应用上的缺点，找出了解决上述问题的办法。     

中小型液压气动与密封企业的信息化方法

我国的液压气动与密封行业,主要由中小企业组成。这些企业,对信息的获取能力、产品的创新设计开发能力、对市场的敏捷能力十分差。随着入关时刻的逐渐来临,如何使得这些中小企业能够应付这些挑战？开展面向中小制造企业的行业型企业联盟的信息化技术研究与应用,旨在为我国的液压行业,建立基于行业型企业联盟理论的信息化平台,实现行业信息的主动获取与服务、基于网络的典型产品协同设计功能,以及面向行业的电子商务,提高该行     

液压密封装置的探索

在液压传动中，液压缸密封装置的优劣直接决定系统性能。本文对液压缸密封装置的分类、密封圈形状、密封材料和密封装置结构进行了分析与研究，给出了典型组合式密封装置的结构形式和所用材料和测试参数，指明了组合式密封装置的应用和研究前景。     

浅谈提高沉降罐伴生气回收率

目前沉降罐伴生气回收技术一般是封闭沉降罐呼吸阀,依靠液压安全阀进行回收,但随着来液量变化,沉降罐分离出天然气量也时刻变化,压力变化幅度大,因此液压安全阀密封液极易在高压时被吹出盛液槽,使油罐和大气直接相通,降低伴生气回收的效率,同时给伴生气的回收工作带来很多不便。目前通过改造,这一问题在长庆油田靖二联已经得到很好地解决。     

开关型闸板防喷器密封胶芯性能试验研究

带压作业密封系统试验台利用液压动力系统输出水压代替油田油水井内部压力,模拟真实油田带压作业起升油管柱修井作业过程,确立开关型闸板防喷器密封胶芯性能试验步骤。利用带压作业密封系统试验台的控制系统进行全程自动化开关型闸板防喷器密封胶芯性能试验,测试油水井井压与密封副驱动力之间关系以及液压驱动力与开关型防喷器胶芯变形关系。     

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.     

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.     

A computer generator for randomly layered structures

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

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to