Ghost的命令行参数及其应用

运用Ghost的命令行参数,可以简化操作过程。本文对各种命令行参数的使用作了一番简要的介绍,并以实例加以说明。     

A sensitivity-based parameterization concept for the automated design and placement of reinforcement doublers

This paper presents a sensitivity-based approach for an automated generation of laminated composite structures with local reinforcement doublers. The method is demonstrated on the problem of finding structural design solutions with maximal frequency-to-mass ratios but can be extended to optimization of different objectives. Eigenvalue sensitivities on finite element level with respect to the thickness of laminate layers are derived analytically and provide the basis for the generation of laminate doublers. Sensitivities can also be evaluated for non-existent layers, namely Ghost Layers. Predefined material properties and orientations are assigned to them but their thickness is specified to zero by a thickness control factor. Assigning a real thickness to parts of these layers, which is controlled by sensitivity information, creates local reinforcement doublers. The locally reinforced solutions are superior to solutions with fully covered layers in terms of eigenfrequency-to-mass ratio. Due to the choice of the parameterization and the iterative thickening process, solutions can be manufactured without significant modifications. The efficiency as well as the solution quality is demonstrated with a numerical experiment.     

P92钢的蠕变行为研究

在不同温度和压力条件下完成P92钢的蠕变及持久试验,采用SEM、TEM研究P92钢的强化机制及退化机制。持久试验外推强度同欧洲蠕变委员会公布的数据基本相同。Norton应力指数数值表明,高应力阶段的蠕变机制为位错蠕变。组织观察结果表明:P92钢的主要强化机制为位错强化及弥散强化,淬火得到的马氏体内部有高密度的位错,板条间的碳化物M23C6及弥散分布碳氮化物MX是P92钢热强性高的原因。随着位错密度的降低及析出相的粗化,P92钢的高温耐热性也降低。     

P92钢的蠕变损伤容许量系数及蠕变断裂机理

利用P92钢在595、610、640、670℃的高应力试验条件下的蠕变试验数据,得出其Norton应力指数,依据Norton应力指数的大小判定其蠕变机理为位错蠕变。同时结合1种新的蠕变变形及断裂模型,引入将蠕变损伤看作1个内在的阶段变量的蠕变损伤容许量系数,根据蠕变损伤容许量λ=2.94,判断其蠕变变形和断裂是位错运动控制的。微观组织的观察也表明,蠕变后的试样中位错密度大大降低,高密度位错是P92钢持久强度高的原因,伴随着位错密度的下降,P92钢持久强度降低直至断裂。     

电路理论结合电路测试技术的探讨

在研究电路理论时,如能注意引进某些电路调试技术的内容,则这些电路理论问题将得到良好的阐释和验证,此外我们还发现,在证明电路中的某些定理时,电路测试技术也能发挥作用。本文就此列举了两个例子:星形与三角形网络等效互换公式的证明以及罗森定理的证明。     

Creep Behavior of Dispersion-Hardened Aluminum Materials

Dispersion-hardened aluminum materials of pure aluminum with extremely fine oxide and carbide dispersions and very fine grain sizes were creep-deformed under compressive loadings between 573 and 773 K. The creep behavior of the investigated materials is influenced by time, temperature, stress level and microstructure. An increasing content of dispersions causes increasing threshold stresses _thand resistances against creep. The Norton plots of the minimum creep rate versus stress are characterized by extremely high stress exponents n. On the basis of the threshold concept it is demonstrated that the same diffusion process dominates in the dispersion-hardened aluminum materials as in pure aluminum. Their true stress exponents n^*as the slopes of the best fit lines of the are close to 5. The threshold stress decreases considerably with increasing temperature due to the thermally activated recovery of long-range internal back stresses of quasi-planar dislocation structures on the grain boundaries.     

一种基于光线光学的杂光分析模型

光学系统的杂散光极易在系统内形成多个鬼像,这不仅严重影响光束质量和传输特性,并可能对系统光学元件造成永久性损伤。该文提出了一种基于光线追迹的分析光学系统杂光影响的有效方法,建立适合各类光学系统杂散光及鬼像分析的数理模型。编制了专门的杂散光分析软件,通过计算机光路模拟,对光学系统中的鬼光束进行全面、系统分析,可得出系统鬼像及关键元件处的能量密度,从而在光学系统设计阶段排除鬼像的潜在危害。     

浅谈实验室计算机硬盘的维护

分析了利用率较高的计算机实验室中计算机硬盘在实验教学中所能遇到的各种故障特征.介绍了相关的硬盘维护及数据修复方法,并对应所存在的故障,针对性较强的设计及改进了对于所存在的问题一贯性的维护及数据修复方法,提高了工作效率,保证正常的教学秩序的顺利进行.     

综合自动化变电站异地备份系统的改进

综合自动化变电站的监控系统在长期的运行过程中会出现软件和硬件的故障,及时备份各变电站的数据,在系统出现故障后可以迅速恢复并保证系统安全。浙江萧山供电局采用了Ghost备份软件对辖区内的各个综合自动化变电站的监控系统进行异地备份,这种软件不仅操作简单,而且可靠性高,大大简化了变电站后台机及远动机系统崩溃后的恢复工作,提高了工作效率和供电的可靠性。     

网络克隆在图书馆电子阅览室中的应用

应用Ghost网络多播克隆技术能实现连网工作站硬盘的批量克隆,这为有效地解决图书馆电子阅览室系统维护提供了一种便捷途径,达到既方便用户又便于管理的目的,从而营造一个良好的检索、咨询环境。