基于风险因子的软件项目风险评价模型

以软件项目的启动过程、计划过程、执行过程、控制过程、收尾过程和项目综合管理能力作为六个风险因子,提出了一个风险评价模型,总结了78个风险指标,依据模型计算出各种风险对进度、成本、范围和质量的综合影响。     

多元线性回归分析在机组发电耗水率中的应用

多元线性回归分析是一个有广泛适用性的多元统计分析方法。本文利用葛洲坝发电站的部分数据,对葛洲坝发电站一段时间内的库水位、出库流量及其对应的机组耗水率利用多元线性回归进行建模分析。显然,对这个问题的深入研究,可以有效地认识各种因素对机组发电耗水率的影响程度,从而可以更好地对机组发电耗水率进行预测。     

基于工作流的高校科研项目管理Petri网建模

科研项目管理是高校科研信息系统的核心部分之一,利用Petri网,对复杂的科研项目管理工作流程建模,解决高校信息化中较为复杂的科研项目管理工作流问题。以高校科研项目申请流程为例,给出了相关定义,分析和解决建模中遇到的几个问题。     

Metal Single-Site Molecular Complex–MXene Heteroelectrocatalysts Interspersed Graphene Nanonetwork for Efficient Dual-Task of Water Splitting and Metal–Air Batteries

Development of multifunctional electrocatalysts with high efficiency and stability is of great interest in recent energy conversion technologies. Herein, a novel heteroelectrocatalyst of molecular iron complex (Fe_MC)-carbide MXene (Mo₂TiC₂T_x) uniformly embedded in a 3D graphene-based hierarchical network (GrH) is rationally designed. The coexistence of Fe_MC and MXene with their unique interactions triggers optimum electronic properties, rich multiple active sites, and favorite free adsorption energy for excellent trifunctional catalytic activities. Meanwhile, the highly porous GrH effectively promotes a multichannel architecture for charge transfer and gas/ion diffusion to improve stability. Therefore, the Fe_MC–MXene/GrH results in superb performances towards oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline medium. The practical tests indicate that Zn/Al–air batteries derived from Fe_MC–MXene/GrH cathodic electrodes produce high power densities of 165.6 and 172.7 mW cm⁻², respectively. Impressively, the liquid-state Zn–air battery delivers excellent cycling stability of over 1100 h. In addition, the alkaline water electrolyzer induces a low cell voltage of 1.55 V at 10 mA cm⁻² and 1.86 V at 0.4 A cm⁻² in 30 wt.% KOH at 80 °C, surpassing recent reports. The achievements suggest an exciting multifunctional electrocatalyst for electrochemical energy applications.     

Abrasion-Resistant and Enhanced Super-Slippery Flush Toilets Fabricated by a Selective Laser Sintering 3D Printing Technology

Flush toilets waste a significant amount of water every day due to the unavoidable adhesions between human waste and the toilet surfaces. Super-slippery surfaces can repel complex fluids and various viscoelastic solids, however, are easily broken by mechanical abrasions. Herein, the fabrication of an abrasion-resistant super-slippery flush toilet (ARSFT) is reported using a selective laser sintering 3D printing technology. Unlike traditional super-slippery surfaces with limited thicknesses which can be easily worn away, the powder-sintered strategy endows the ARSFT not only with a self-supporting 3D complex shape but also with a porous structure that can accommodate considerable lubricants for an abrasion-resistant super-slippery property. As a result, the as-prepared ARSFT remains clean after contacting with various liquids such as milk, yogurt, highly sticky honey, and starch gel mixed congee, demonstrating excellent repellence to complex fluids. Besides liquids, the ARSFT exhibits a high resistance to sticky synthetic feces. Notably, even after being abraded to 1,000 cycles of abrasion using sandpaper, the ARSFT maintains its record-breaking super-slippery capability. The concept of the 3D-printed object with a superior abrasion-resistant slippery ability will improve the development of super-slippery materials and further save water consumption in the human society.     

改革实践教学模式、培养学生综合能力──增设给水排水专业质量检测实习的体会

对给排水专业在优化专业教学体系,深化专科教学模式及教学内容改革中,实施的四次大型综合性实践教学,进行了认真总结．经过改变随课跟进的实验教学旧模式,在教学计划中增设了“水质指标综合测试与水质评价”实习内容使分散的教学实验得以“水质监测与评价”为骨架,有机穿插在实践教学中,为专科学校培养复合应用型人才,进行了有益的探索与实践,并获得较好效果．     

煤矿机电及运输事故防治的紧迫性研究

分析了2005—2010年全国煤矿死亡事故中顶板、瓦斯、水灾、火灾、运输、机电、爆破等各类事故数占事故总数的比例及每起事故的平均死亡人数,指出运输和机电事故死亡人数分别居第3位和第5位,共占死亡总人数的13.72%;指出电气火源是引爆瓦斯的第一火源,且2010年由机电事故引发的矿井火灾占火灾事故总数的80%,得出加强煤矿机电事故防治工作是遏制瓦斯爆炸事故及矿井火灾的迫切需要的结论;最后指出,应加强机电及运输事故防治工作,以减少由煤矿机电、运输事故引发的瓦斯爆炸事故和火灾事故。     

基于PLC的变频节能系统在井筒冻结施工中应用的研究

针对冻结施工法装机容量大、电能消耗高以及施工过程的阶段性特点,在分析了冻结系统螺杆盐水机组不同工况下的机械特性和在各个冻结阶段电能消耗情况下,设计了一种基于PLC的变频节能系统。该系统以PLC为控制核心,通过压力传感器、液位计等对系统工况信息进行反馈,利用PID算法控制变频器的输出频率,从而达到了调节盐水泵流量、控制供冷量的目的。实验数据论证了该系统在井筒施工中应用的可行性与高效性。     

职业学校课程项目化教学改革

项目化教学是一种面向就业市场的新型教学模式,正逐步走进职业学校的课堂。在获得师生认可的同时,该教学方式在教学改革中体现出的矛盾也十分突出。本文对当前职业学校课程项目化教学改革中的诸多问题进行系统分析,提出比较现实的解决对策及具体的实施过程。