具有混合边界透水条件的多孔饱和半空间上刚性圆板的垂直振动

用积分变换和积分方程研究多孔饱和半空间上刚性圆板的垂直振动问题。首先应用逐次解耦方法求解多孔饱和固体的动力基本方程－Ｂｉｏｔ波动方程。然后考虑混合边界透水条件（半空间表面与圆板的接触面是不透水的,而其余表面是透水的）,建立子多孔饱和半空间上刚性圆板垂直振动的对偶积分方程,并化对偶积分方程为第二类Ｆｒｄｄｈｏｌｍ积分方程。     

信息安全遵从行为的激励机制研究——惩罚的确定性与适度性

关于惩罚的确定性及其严重性是否能够有效地影响组织内部雇员的信息安全遵从行为,已有的研究结论尚存在着严重分歧。为了继续探索惩罚对信息安全遵从行为的影响作用,构建了信息安全遵从博弈模型,依据该模型和存在道德风险的委托人——代理人理论,分析了惩罚的确定性以及适度的惩罚严重性对信息安全遵从行为的激励机制,并对惩罚的适度性进行了数值模拟。研究表明:(1)作为委托人的组织可以设计出包含适度惩罚的最优激励契约,并获得最优的信息安全遵从收益;作为代理人的雇员不仅将接受该契约,并且会按照组织所期望的努力水平去遵从信息安全制度。(2)惩罚的确定性和适度性两者能够有效地影响雇员的信息安全遵从行为。(3)组织可以根据雇员的风险规避测度、外部机会收益、激励报酬以及信息安全产出结果这四个因素来设置适当的惩罚额度。这些研究结果将有助于信息安全管理者深入地理解并有效地管理组织内部雇员的信息安全遵从行为。     

Mathematical and numerical approaches to a one-dimensional dynamic thermoviscoelastic contact problem

In this paper, we propose numerical schemes for solving a nonlinear system which consists of a coupled partial differential equations and two conditions, called normal compliance contact condition and Barber’s heat exchange condition. The convergence of numerical trajectories is shown by using a time discretization and passing the limit of the time step size. The uniqueness of the weak solution is proved as well. We derive the extensive form of an energy balance which will be a criterion to examine numerical stability. An example is provided to present and discuss numerical results.     

Viscoelastic modeling of nanoindentation experiments: A multicurve method

Nanoindentation is an increasingly used method of extracting surface mechanical properties of viscoelastic materials, especially polymers. Recently, Hutcheson and McKenna used a viscoelastic contact mechanics model to analyze the contact problem between a nanosphere and polystyrene surface. In nanoindentation experiments, the ramp loading test is a similar problem to the particle embedment experiment except that the indentation load function differs. The motivation in this work is to expand the Hutcheson and McKenna analysis to the nanoindentation problem. In particular, we illustrate the limitations of analyzing only a single load‐indentation curve, which does not provide enough information to determine the full range of the viscoelastic response of a polymer, and we show that performing a test sequence that includes multiple loading rates or indentation rates spanning two or more orders of magnitude greatly improves the extracted viscoelastic properties. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 633–639     

TORSIONAL VIBRATIONS OF A RIGID CIRCULAR PLATE ON SATURATED STRATUM OVERLAYING BEDROCK

The torsional vibration of a rigid plate resting on saturated stratum overlaying bedrock has been analysed for the first time. The dynamic governing differential equations for saturated poroelastic medium are solved by employing the technology of Hankel transform. By taking into account the boundary conditions, the dual integral equations of torsional vibration of a rigid circular plate are established, which are further converted into a Fredholm integral equation of the second kind. Subsequently, the dynamic compliance coefficients of the foundation on saturated stratum, the contact shear stress under the foundation and the angular amplitude of the foundation are evaluated. Numerical results indicate that, when the dimensionless height is bigger than 5, saturated stratum overlaying bedrock can be treated as saturated half space approximately. When the dimensionless frequency is low, the permeability of the soil must be taken into account. Furthermore, when the vibration frequency is a constant, the height of the saturated stratum has a slight effect on the dimensionless contact shear stress under the foundation.     

有关力学谱和内耗工作的综合与回顾(英文)

本文广泛地收集了有关内耗,力学谱,超声衰减方面的专著及会议文集。反映了20世纪在此领域的英文,俄文出版的书籍。也列出了历次国际会议及前苏联,乌克兰,中国的国内会议。文中包括了点缺陷,电,声子,位错,晶界,电畴等诸方面在内的内耗与力学谱工作。     

健康教育对盆腔炎患者的临床影响分析

目的分析健康教育对盆腔炎住院患者的积极影响。方法选取2013年4月—2014年11月江门市人民医院接收的87例盆腔炎患者为研究对象,将其分为对照组(44例)施以常规护理,观察组(43例)在对照组基础上进行健康教育,对两组患者的健康教育知识掌握程度、疗效及护理满意度进行比较。结果观察组疾病认知达标率为95.35%,对照组81.82%(P0.05);观察组总有效率为93.02%,对照组79.55%(P0.05)。结论健康教育可有效提高盆腔炎患者对疾病认知程度,提高治疗效果,进而增加护理满意度。     

Nanoindentation creep of nonlinear viscoelastic polypropylene

Uniaxial tensile creep tests at various applied stresses were carried out to demonstrate that PP is nonlinear viscoelastic. A novel phenomenological model consisting of springs, dashpots, stress-locks and sliders was proposed to describe the nonlinear viscoelasticity. Indentation creep tests at different applied load levels were also performed on nonlinear viscoelastic PP. It was found that the shear creep compliance varies with the applied load level when the applied load is less than 5 mN, which means the indentation creep behavior was nonlinear. To find the real reason for the nonlinearity in indentation creep tests, the elastic modulus at various indentation depths was measured using continuous stiffness measurements (CSM). By analyzing the variation of elastic modulus with indentation depth, the nonlinearity of indentation creep behavior was proved to be caused by the non-uniform properties in the surface of the specimen rather than nonlinear viscoelasticity.     

引用自动检测系统测定HG60RA钢400℃时的da/dN

详细介绍了以降载柔度法为原理用ＩＢＭ－ＰＣ微机采集数据的高温低周疲劳裂纹扩展速率自动检测系统，运用此系统研究了ＨＧ６０ＲＡ钢在４００℃时的低周疲劳裂纹扩展速率，得到了ＨＧ６０ＲＡ钢在４００℃时的ｄａ／ｄＮ－ΔＪ关系．试验结果表明检测系统有很高的测量精度，能用于金属材料疲劳裂纹扩展速率的自动检测．