焦化氨水介质中0Cr17Ni12Mo2不锈钢电化学腐蚀行为研究

采用全浸动态挂片和极化曲线实验法研究0Cr17Ni12Mo2不锈钢在模拟现场工况条件下的腐蚀行为。结果表明,0Cr17Ni12Mo2试样的腐蚀速率随温度的升高不断加快;增大硫离子和氯离子浓度可使0Cr17Ni12Mo2试样腐蚀速率加快;氰根离子浓度不高于临界值时,试样腐蚀速率减缓,反之,腐蚀速率加快。     

高速公路隧道边坡稳定性分析与加固措施选择

对巫奉高速公路某隧道进口边坡的工程地质条件进行勘察,并依此进行边坡稳定性分析。通过研究得出几种边坡加固措施,并由力学计算与分析得出以"注浆+锚索加固"为最优方案,可以使边坡稳定性系数提高至1.25以上。现场应用表明,"注浆+锚索加固"方案效果显著,可以为类似边坡加固工程提供参考。     

外部环境干扰下的非线性渔业资源种群动力模型及分析

运用欧拉方法获得离散的捕食者-食饵差分系统方程,并考虑添加一对捕食者的扰动项后建立了一外部环境干扰下的非线性渔业资源种群模型,从而定量分析正不动点的存在性、稳定性和局部分叉,发现系统可能产生Neimark分叉和倍周期分叉,用全局分析方法描述了资源在什么范围具有可持续性利用,即保持渔业资源种群数量不枯竭的资源储量范围.     

基于兴趣点特征的多类物体识别

针对多类物体识别中计算量大、识别率低等问题,在现有模拟视觉系统的计算模型基础上,对原模型进行了改进,提出了改进模型.首先,通过有效的算法提取图像中的兴趣点,并以此为中心选择适当尺度的小块作为特征模板,从而提高模板有效性;然后,确立了以固定兴趣点个数的方法来选择兴趣点,从而解决多类物体识别中兴趣点选取的阈值问题.对多类物体分类识别的实验结果表明:改进后的模型比原有模型具有更快的识别速度和更高的识别率.     

Molecular dynamics simulation of injection of polyethylene fluid in a variable cross-section nano-channel

Numerical simulation of injection of polyethylene fluid in a variable cross-section nano-channel was carried out using the molecular dynamics method.The effects of the nano-channel cross-section and the external force on the rheological behavior and structural properties of the polyethylene fluid were investigated.It was found that an absorbed layer appeared near the wall and the thickness of the absorbed layer increased with increasing cone angle of the nano-channel.The injection distance of the polyethylene fluid decreased with increasing cone angle and decreasing external force.In the nano-channel with cone angle 45°,polyethylene particles uniformly filled the whole channel and were stretched along the flow direction.Uniaxial stretching of particles was enhanced when the external force was strengthened,which facilitates injection of the polyethylene fluid into the nano-channel.     

A note on stability of the split-step backward Euler method for linear stochastic delay integro-differential equations

In the literature(Tan and Wang,2010),Tan and Wang investigated the convergence of the split-step backward Euler(SSBE) method for linear stochastic delay integro-differential equations (SDIDEs) and proved the mean-square stability of SSBE method under some condition.Unfortunately, the main result of stability derived by the condition is somewhat restrictive to be applied for practical application.This paper improves the corresponding results.The authors not only prove the mean-square stability of the numerical method but also prove the general mean-square stability of the numerical method.Furthermore,an example is given to illustrate the theory.     

切铅机定位系统改造

现阶段雷管生产中延期时间的控制,主要采取加装铅延期体,铅延期体质量和生产效率直接影响雷管质量与雷管产能。文章介绍了一种切铅设备的改进,提高铅延期体质量和生产效率。     

How to do the Audit of Project Budget and Settlement

工程预结算审核主要内容包括合同审查、图纸审查、参与图纸会审、设计变更论证等,深入现场,了解工程实际情况、审核工程量、套用单价计价、费用审核,认真审核现场签证.     

Enriching Service Learning by its Diversity: Combining University Service Learning and Corporate Social Responsibility to Help the NGOs Adapt Technology to Their Needs

Community-based service learning helps students link subject matter to everyday life and developing sense of responsibility to their community. Corporate social responsibility (CSR) is a form of corporate self-regulation integrated into a business model. Both promote civic engagement but the two hardly come across each other. We explore the process that enriched service learning with its diversity by combining CSR practices of a multinational software company. It begins by exploring different forms of action research with a focus on action engagement to improve students’ involvement in marginalized communities. The article provides field-based reflections of the sustained engagement and suggests ways in which service learning experiences may create rooms for innovation and growth in the non-profit sector, local communities, businesses, and students themselves.