圆形截面混凝土偏心受压构件极限承载力的理论分析

根据混凝土材料非线性的应力—应变关系,采用非线性分析的方法,对圆形截面的混凝土偏心受压构件的极限承载力做了理论计算,建立了荷载偏心对承载力影响的折减系数计算方法,为简化计算方法提供了理论依据     

压电磁耦合振动能量俘获系统的非线性模型研究

为了建立压电磁耦合振动能量俘获系统的动力学模型,提出了一种非线性多项式拟合系统的非线性回复力的建模方法。使用微型测力仪直接测得悬臂梁处于不同位置时的非线性回复力,并用多项式进行参数拟合以获得非线性回复力的表达式。根据哈密顿原理、欧拉-伯努利梁理论和压电理论等,建立了考虑非线性回复力的系统模型,由龙格-库塔数值算法仿真后得到系统的非线性输出特性。研究结果表明,该模型具有参数求解简单、计算量小、无需直接求解磁场力等优点,能够描述非线性宽频能量系统的跳跃频率、最大电压和有效频带等关键设计参数,为压电磁耦合振动能量俘获系统的机理研究奠定了理论基础。     

考虑温度效应的风电增速箱动力学特性研究

针对风电增速齿轮箱温度异常现象,基于Block闪温理论与Hertz接触理论,提出一种考虑随机风载作用下齿面接触温度的计算方法.以该方法为理论基础,根据行星轮系耦合建模理论,建立风电增速齿轮箱动力学性能计算模型.模型不仅揭示了随机风载、齿面接触温度及齿廓热变形之间相互影响的函数关系,还展现了随机风载、齿面接触温度等非线性...     

高分子熔体和浓溶液流变性能的研究──（I）具有Nagai缠结链限制作用下高分子熔体的非线性粘弹性分子理论

根据多重缠结模型和多重蠕动机理．用统计力学和动力学相结合的方法．建立了具有缠结限制作用的非线性粘弹性分子理论，计算了处于多重缠结态高分子链的构象统计．得到了高聚物熔体的粘弹性形变自由能，推导出了４种简单形变方式下的应力－应变关系、高分子流体的回忆函数、简单剪切流下的物料函数．推出了一种测定参数η０，ｎ’和ａ的新方法．从理论和实验上证实了非线性粘弹性理论的时间效应和形变影响是相互独立的．并以聚乙烯，聚丙烯和聚苯乙烯熔体的大量流变性能实验数据加以验证．结果证明，该理论能较好地预测高聚物熔体的非线性和线性粘弹性力学行为．     

GMDH－EPTSV建模方法及其应用

对于多变量非线性系统，根据控制理论中的自组织原理，提出了改进的主成分分析双向量选择的数据处理组合方法，简称ＣＭＤＨ－ＥＰＴＳＶ方法建立了合成氨系统的数学模型，该方法有较好的模型精度和计算稳定性。     

非线性动力系统理论在机械故障诊断中的应用

从非线性动力系统理论的角度出发，对非线性动力系统进行了分析，据此建立了数学模型，并应用于实际的物理系统中．根据对Ｌｉａｐｕｎｏｖ指数的计算，分析了在非线性问题处理中各方法的优劣及其可靠性．作为尝试，文中试图利用非线性方法对故障进行分类，并对系统进行定性预测分析．实际结果表明在一定程度上是较为成功的     

模拟退火方法的改进及其在地震剩余静校正中的应用

分析了模拟退火非线性反演方法随机寻优的特点,提出了一种改进的具有较高计算效率的模拟退火方法,该方法采用数论中的均匀试验设计方法来建立候选解在解空间的均匀分布,少量的目标函数计算就能了解目标函数解空间性质,减少了目标函数的计算次数.理论和实际计算表明该方法具有较高的计算效率.     

基于泛形理论与概率统计理论的结合面接触刚度分析

泛形理论是根据分形理论逐渐发展而来的一种表征复杂几何形态的非线性方法。针对分形理论中结合面微凸体接触无限趋近于零的不合理现象,依据泛形理论和概率统计理论建立了粗糙表面与刚性平面接触的法向接触刚度数值模型。数值计算表明,法向接触刚度与复杂度表现出明显的非线性关系,并且随着复杂度的增大,接触刚度也随之增大。研究结论可供精密制造装备提供设计依据。     

钢管混凝土拱桥空间稳定非线性分析

文章采用有限元软件ANSYS建立了钢管混凝土拱桥的空间模型,计算了4种工况下的线弹性、几何非线性和双重非线性稳定安全系数,并根据计算结果,评价了桥梁的整体稳定性,分析结果为同类型桥梁的空间稳定分析提供参考。     

设置FVD框架结构的非线性地震反应控制研究

根据粘弹性阻尼器和摩擦阻尼器各自的特点,设计出一种新型粘弹性-摩擦阻尼器(FVD)耗能装置．针对粘弹性材料的分数导数模型和摩擦单元的力-位移-滑移量的矩阵关系式,建立了FVD精确的有限元模型,推导了FVD单元刚度矩阵和控制力向量计算公式和求解方法;根据钢筋混凝土框架结构的非线性特性,建立了设置FVD非线性钢筋混凝土框架结构地震反应时程分析的控制方法．最后,应用本文方法,对设置FVD的非线性钢筋混凝土框架结构进行了在罕遇地震和多遇地震作用下的时程分析,并根据计算结果对其减震效果进行了分析讨论．     

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.     

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.     

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。     

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.