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1.
对轨道电路故障判断分析方法的探讨   总被引:1,自引:0,他引:1  
陆晓东 《甘肃科技》2003,19(5):39-41
经过实际验征,对轨道电路故障的判断得出了一种简学易引的方法,文章即对此方法进行说明,以对实际问题进行指导。  相似文献   

2.
双网卡冗余在嵌入式容错网络中的设计与实现   总被引:3,自引:0,他引:3  
为了尽量避免嵌入式网络中网络节点故障和链路故障所带来的损失,在容错网络中,需要经过良好设计的故障恢复方案,以便于在网络通信中获取较高的可靠性和易用性。提出并详细介绍了一种基于双网卡的网络冗余方法,该方法包含了故障检测和故障恢复方法,故障检测方法使用链路状态检测与Loop-back检测相结合的方式;故障恢复方法在发现激活物理层故障后,将引导系统使用备用物理层。这种网络冗余方式的实现有效地提高了嵌入式网络设备的通信可靠性,又由于实现方便,造价低,可靠性高的特点,使其在现实的容错网络中获得了广泛的应用。  相似文献   

3.
分析了雷击致使彩电损坏的原理,指出了雷击的主要途径是从交流电源进入彩电,给出了雷击彩电的一些特殊故障的维修实例,提出了雷电条件下收看电视的要求及防止雷击的措施。  相似文献   

4.
面向故障的软件测试方法正在快速发展中,应用这种方法的关键之一就是定义各种故障模式。本文针对涉及软件性能方面的几类Java语言故障模式,给出其一般形式和产生原因,并分析其对于保证软件质量的重要性及改进措施,最后简要介绍了对故障模式进行检测的方法。  相似文献   

5.
本文论述了低压系统接地故障及其成因和几种常用的接地方式,阐明了造成接地故障引发火灾的原因,提出了接地故障引发火灾的防范措施。  相似文献   

6.
生产过程故障诊断方法研究现状及展望   总被引:4,自引:0,他引:4  
回顾了过程故障诊断技术的研究历史,对已形成的故障诊断方法分三类进行了总结,特别对近年来形成的基于数据分析的方法进行了分析,最后指出了过程故障诊断技术现存的问题,同时指明了故障的预报方法、辨识方法、诊断系统的鲁棒性和非线性研究以及大型、实用故障系统的构建将是该领域研究中近期的发展方向。  相似文献   

7.
电子电路的故障检测   总被引:1,自引:0,他引:1  
检测电路故障的方法,应根据电路的简繁程度、装配方法、仪器设备的装备情况来决定。为方便检测电子电路的故障,简要介绍了常用方法,包括直接观察法、参数测试法、信号寻迹法、对分法、分割测试法、对比法、替代法及电容器旁路法。  相似文献   

8.
软件测试是排除软件故障,提高软件质量和可靠性的重要手段。从是否需要执行被测程序角度考虑,软件测试分为静态测试和动态测试。动态测试通过输入测试数据,动态执行程序来发现软件中存在的错误。尽管动态测试能发现部分软件错误,但对于一些特殊类型错误的检测无效。鉴于此,本文采取了一种特殊的静态分析技术来实现对代码的测试。本文首先讨论了传统软件测试方法的缺点和局限性,给出了软件的故障模型,进而提出了基于抽象语法树的静态分析技术,并给出了故障自动检测算法。依据该算法开发了自动化测试工具,给出了实验结果和对比分析,并指出了下一步的研究方向。  相似文献   

9.
SSCK系列数控车床的致命度分析   总被引:1,自引:0,他引:1  
通过对7台数控车床故障数据进行分析,查清了各故障部位、故障模式的比率,建立了失效模式影响及致命性分析(FMECA)表,从而为可靠性分析和可靠性设计提供了依据  相似文献   

10.
介绍了Oracle数据库故障类型、故障恢复方法及故障恢复所使用的数据结构,给出了两个故障恢复实例,为Oracle数据库系统管理损恢复故障提供有益的经验和技巧。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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。  相似文献   

20.
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.  相似文献   

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