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.     

中国地图学百年回顾与展望

地图的产生和发展是人类生产和生活的需要.地图学是研究有关地图的理论体系和技术系统及其应用的学科,它是建立在正确的地理认识基础上的图形显示的技术科学.     

优先放行的环形快速路入口匝道控制

针对城市快速路因交通需求大于交通供给而出现的交通拥堵现象,考虑入口匝道处车辆对城市快速路优先使用权的需求,通过分析优先放行的效益,提出了优先放行的入口匝道控制策略,即在交通高峰期让等级较高的车辆优先进入城市快速路.文中还研究了优先放行的城市快速环形路段算法,并给出了具体的算例.结果表明:将该策略运用到入口匝道控制上,能限制等级较低的车辆进入,提高道路的使用效率.     

Mechanical properties of electroformed copper layers with gradient microstructure

The electroformed copper layer with gradient microstructure was prepared using the ultrasonic technique. The microstructure of the electroformed copper layer was observed by using an optical microscope (OM) and a scanning electron microscope (SEM). The preferred orientations of the layer were characterized by X-ray diffraction (XRD). The mechanical properties were evaluated with a Vicker’s hardness tester and a tensile tester. It is found the gradient microstructure consists of two main parts: the outer part (faraway substrate) with columnar crystals and the inner part (nearby substrate) with equiaxed grains. The Cu-(220) preferred orientation increases with the increasing thickness of the copper layer. The test results show that the microhardness of the electroformed copper layer decreases with increasing grain size along the growth direction and presents a gradient distribution. The tensile strength of the outer part of the electroformed copper layer is higher than that of the inner part but at the cost of ductility. Meanwhile, the integral mechanical properties of the electroformed copper with gradient microstructure are significantly improved in comparison with the pure copper deposit.     

高职高专体育教育专业课程体系改革研究

为探索高职高专体育教育专业课程体系优化设计,以我校体育教育专业课程体系作为实践改革试点对象,构建了以体育教学应用能力模块、运动技能模块和职业综合素质模块三大模块为内容的体育教育专业课程体系,指出了高职高专体育教育专业课程体系设计的影响因素,并提出了改革方案。     

Improved Oustaloup approximation of fractional-order operators using adaptive chaotic particle swarm optimization

A rational approximation method of the fractional-order derivative and integral operators is proposed. The turning frequency points are fixed in each frequency interval in the standard Oustaloup approximation. In the improved Oustaloup method, the turning frequency points are determined by the adaptive chaotic particle swarm optimization (PSO). The average velocity is proposed to reduce the iterations of the PSO. The chaotic search scheme is combined to reduce the opportunity of the premature phenomenon. Two fitness functions are given to minimize the zero-pole and amplitude-phase frequency errors for the underlying optimization problems. Some numerical examples are compared to demonstrate the effectiveness and accuracy of this proposed rational approximation method.