基于PXI总线的虚拟仪器测试系统

本文介绍了新一代仪器总线技术PXI的性能和应用领域,讨论了虚拟仪器技术的概况和基于PXI总线的虚拟仪器测试系统架构及软硬件设计。     

基于虚拟仪器技术的电子设备测试系统

通过对基于Lab Windows／CVI的虚拟仪器的开发平台的研究,提出了用于电子设备的通用测试系统的设计方案,主要由通用计算机和基于PXI、GPIB总线技术的功能化硬件模块组成。用户可以通过编写测试软件驱动硬件平台,代替传统的仪器完成测试任务。由于可以按照自己的需求设定测试任务,因此能够实现测试平台的通用化,最大限度地减少了仪器的数量,同时也提高了测试系统的可维护性。     

基于PXI总线和虚拟仪器的高速数据采集系统

系统地介绍运用PXI总线和虚拟仪器等测试领域新技术,进行高速数据采集系统的研发,以及克服其他低速总线数据传输的"瓶颈"的方法,并阐述了虚拟仪器代替传统仪器开发测试系统的过程和优缺点.     

基于TEDS传感器和虚拟仪器技术的测试系统设计与实现

针对传统机械测试系统中存在的仪器操作复杂、配置调试时间长、功能单一等缺点,设计了一套基于TEDS传感器和虚拟仪器技术的测试系统.采用先进的1-wire和PXI总线搭建了硬件平台.通过将TEDS植入传统传感器内,使得传感器具有自我标识的能力.基于虚拟仪器平台的TEDS传感器、自动配置线路、数据采集及分析等功能模块使用方便并可根据用户的需要进行定制.实验证明,该系统具有较强的实用性,代表了未来机械测试系统的一种发展方向.     

下一代测试自动化总线技术--LXI

LXI是继GPIB仪器、VXI/PXI虚拟仪器之后的、新一代基于以太网络LAN的总线技术,适用于自动测试系统的模块化仪器平台标准.本文依据有关LXI的最新报道及测试技术和相关科学技术现状,介绍了GPIB、VXI、PXI、LXI的历史发展轨迹及各自的优缺点,重点分析了基于LXI平台下的模块化仪器的特点和优势,最后简要介绍了LXI所面临的问题及其应用前景.     

基于PXI总线的电子装备测试系统设计

PXI总线电子装备测试系统是将基于PXI总线的虚拟仪器技术,应用于航空电子装备的测试。针对航空电子装备的测试需求、系统开放性和可扩展的要求,设计研制了一套基于PXI总线的检测设备。详细说明了基于PXI总线的电子装备测试系统的硬件构成和软件设计方法。该系统以PXI内嵌主控计算机为核心,以LabVIEW软件为开发环境,并综合运用标准接口和总线技术来实现系统的综合设计。通过设计测试证明该系统方案切实、有效。     

采用SOA技术解决虚拟仪器技术发展中遇到的问题

本文叙述了虚拟仪器技术的特点、组成架构及发展历史,以及当前虚拟仪器技术发展存在的问题,并提出了基于SOA(面向服务的体系架构)技术解决这些问题,随着计算机技术和网络技术的发展,多仪器协同工作在各种应用领域成为必然,基于SOA技术能很好的整合应用系统。     

基于DataSocket的虚拟仪器技术在设备远程状态监测与故障诊断中的应用

虚拟仪器技术是计算机系统与仪器系统相结合的产物。DataSocket技术是面向网络化测试的技术,支持实时数据交换传输。本文介绍了如何基于DataSoeket的虚拟仪器技术实现设备远程状态监测与故障诊断,并基于DataSocket的虚拟仪器技术开发了一套远程状态监测与故障诊断系统。     

论电子技术试验中对虚拟仪器的有效运用

在计算机技术、测试仪器及相关技术的发展背景下,仪器接口总线方式不断丰富和完善,为电子技术试验中虚拟仪器的运用提供了基础。相比于传统仪器,虚拟仪器实现了应用功能及范围上的延展,在电子技术试验中提供了更为方便、快捷、灵活的应用方式,其实践价值效力毋庸置疑。时至今日,有关电子技术试验中对虚拟仪器有效运用的学术研究备受关注,并成为现代科技发展的重要议题。本文基于对虚拟仪器的概述及分析,就其在电子技术试验中的有效运用进行了探究。     

一种用于测试技术教学实验的网络虚拟仪器实验室

网络虚拟实验室是目前国内外研究的热点和实验教学的发展方向,本文综合利用计算机技术、虚拟仪器技术和网络技术,提出了基于网络的虚拟仪器实验室的系统结构。本系统以测试技术教学实验室建设为对象,针对测试专业特点,基于浏览器/服务器构架和LabVIEW软件,设计虚拟仪器实验室平台,并将虚拟仪器在网页上进行发布,用户可通过浏览器访问和操作仪器,并实时观察结果。     

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.     

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.     

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.     

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.     

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.     

A computer generator for randomly layered structures

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

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.     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.