摘要：软件设计模式是经分类编目的关于代码设计经验的系统总结。一个良好的应用软件设计,不仅可增加代码的可维护性,而且还可提高软件系统的灵活性和可扩展性,起到事半功倍的效果。以水文站信息推送APP框架设计为例,以观察者模式为研究对象,具体说明设计模式在水文信息化软件开发过程中的应用。

摘要：Hydrogen,regarded as a promising energy carrier to alleviate the current energy crisis,can be generated from hydrogen evolution reaction(HER),whereas its efficiency is impeded by the activity of ***,effective strategies,such as strain and interfacial engineering,are imposed to tune the catalysis performance of novel two-dimensional(2D)phosphorus carbide(PC)layers using first-principle *** findings show that P site in pristine monolayer PC(ML-PC)exhibits higher HER performance than C ***,constructing bilayer PC sheet(BL-PC)can change the coordinate configuration of P atom to form 3-coordination-P atom(3-co-P)and 4-coordination-P atom(4-co-P),and the original activity of 3-co-P site is higher than the 4-co-P *** an external compressive strain is applied,the activity of the 4-co-P site is enhanced whereas the external strain can barely affect that of 3-co-P ***,the graphene substrate enhances the overall activity of the BL-PC because the graphene substrate optimizes the?GH*value of 4-co-P site,although it can barely affect the HER activity of 3-co-P site and *** desirable properties render 2 D PC-based material promising candidates for HER catalysts and shed light on the wide utilization in electrocatalysis.

摘要：为进一步提高力流变抛光效率与抛光质量,提出振动辅助力流变抛光方法。对不锈钢振动辅助力流变抛光加工过程中,工件材料去除过程及不同工艺参数对抛光特性影响进行研究。基于振动辅助力流变抛光原理及试验,以材料去除率和表面粗糙度为评价条件,分析了抛光速度、振动频率和振幅3个关键参数对抛光影响规律。基于田口法设计试验,采用信噪比评估试验结果并得出优化的工艺参数,通过方差分析法得出各因素的权重。结果表明:抛光速度对材料去除率影响最大,振幅次之,振动频率影响最小;抛光速度对表面粗糙度影响最大,振动频率次之,振幅影响最小。在优选的抛光参数组合下,抛光速度40 r·min^(-1)、振幅0.35 mm、振动频率80 Hz,加工30 min后工件表面粗糙度由(80±10)nm下降至(7.1±0.9)nm,其材料去除率达到68 nm·min^(-1)。受振动的抛光液中粒子间发生相对相位差并形成一定的剪切速率,使抛光液产生流变效应并把持游离磨粒。在相对运动作用下对工件表面施加压力及剪切力,以塑性去除方式实现不锈钢材料去除。利用所提方法,在优化工艺参数下可有效去除不锈钢表面划痕,提高表面质量。

摘要：本文介绍了一种高速CAN总线称重仪表,该仪表集成了CANopen协议,以及仪表与传感器通信的内部CAN协议。文中对称重仪表CAN接口电路、CANopen应用协议及内部CAN协议设计的关键点进行了重点阐述。

摘要：铁路用地管理比较重要,结合实际情况,需要从实际情况入手,做好实际管理工作,提升可行性。当前铁路建设在改革以及发展时期,为了起到深化资产运营的优势,在现有基础上进行合理化部署和管理,能提升整体稳定性。集中设计和部署是关键,在整个管控过程中实现信息管理系统的有序应用,使其符合规范化要求,实现整体进步。