混凝土结构的劣化分析与控制

结构混凝土的劣化常常导致结构过早地进行维修或拆除,甚至发生严重事故.有些基层结构设计工程师在设计中往往仅考虑结构的受力状态及变形程度,而对混凝土随时间和环境变化产生性能劣化的认识不清,重视不够.从混凝土自身形成过程、混凝土状态特点与环境因素间相互作用方面,定性分析了其内部损伤发展的各个阶段及影响机理,并结合多年在污水处理工程上的设计经验及有关规范要求,在工程设计、施工管理及使用维护方面提出一些控制措施,以利于建筑物、构筑物使用寿命的提高.     

嵌入式智能家居系统

以ARMv5E的Xscale微处理器PXA270为控制核心,设计开发了符合用户需要的具有网络功能的家居系统。介绍了嵌入式智能家居系统的总体结构,描述了各功能模块的软硬件设计思想,设计了温湿度检测电路,继电器控制电路和以太网接口电路,实现通过互联网或GPRS网络监视和控制家居设备的功能,为进行智能家居设计提供了设计参考。     

基于nRF24E1的智能家居组网技术研究

给出了以nRF24E1芯片的智能家居无线组网新方法。设计一个主节点节点和多个从节点节点构成的星型结构智能家居网络。介绍了智能家居无线组网系统的总体结构和工作原理,给出了硬件电路和软件设计方案。该组网方案针对智能家居设计,具有成本低,结构简单,可靠性强,功能易扩展,实用性强等优点。     

Smart elasto-magneto-electric （EME） sensors for stress monitoring of steel structures in railway infrastructure

Steel structures are widely used in railway infrastructures. Their stress state is the most important determinant of the safety of these structures. The elasto-magnetic (EM) sensor is the most promising for stress monitoring of in-service steel structures. Nevertheless, the necessity of magnetic excitation to saturation due to the use of a secondary coil for signal detection, keeps from its engineering application. In this paper, a smart elasto-magneto-electric (EME) sensor using magneto-electric (ME) sensing units to take the place of the secondary coil has been exploited for the first time. The ME sensing unit is made of ME laminated composites, which has an ultrahigh ME voltage coefficient and can measure the magnetic induction simply and precisely. Theoretical analysis and characterization experiments firstly conducted on the ME laminated composites showed that the ME sensing units can be applied in the EM sensor for improved performance in stress monitoring. A tension test of a steel bar was carried out to characterize our smart EME sensor and the results showed high accuracy and sensitivity. The present smart EME sensor is a promising tool for stress monitoring of steel structures in railway and other civil infrastructures.     

以教学行为为关键线索的智慧校园探究

如何以平台数据为驱动来实现智慧教育教学,是国内外智慧校园建设亟待解决的一个重要问题。文章将教学行为作为智慧业务实施的关键线索,剖析了教学过程的参与对象和相关的"教"行为、"学"行为,按照工程设计规范,设计了智慧校园的对象模型和功能模型;同时,在智慧校园中引入学习分析机制,进行了智慧校园数据的统计与应用、流程的跟踪和监控、分析结果的预测和决策等。在此基础上,文章提出了包含教学行为、资源管理、教学环路、智慧决策、教学评价等五大模块的智慧校园架构方案,可为教育大数据背景下建设智慧校园、实现智慧教育教学提供有效思路。     

Inquiry-Based Science and Technology Enrichment Program for Middle School-Aged Female Students

This study investigates the effects of an intensive 1-week Inquiry-Based Science and Technology Enrichment Program (InSTEP) designed for middle school-aged female students. InSTEP uses a guided/open inquiry approach that is deepened and redefined as eight sciences and engineering practices in the Next Generation Science Standards, which aimed at increasing female students’ interest in science and science-related careers. This study examined the effectiveness of InSTEP on 123 female students’ pre-assessment and post-assessment changes in attitudes toward science and content knowledge of selected science concepts. An attitude survey, a science content test with multiple-choice questions, written assignments, and interviews to collect data were all used to measure students’ attitudes and content knowledge. A within-group, repeated measure design was conducted, and the results indicated that at the post-intervention level, InSTEP increased the participants’ positive attitudes toward science, science-related careers, and content knowledge of selected science concepts.     

形状记忆合金智能混凝土结构研究进展

形状记忆合金作为一种智能材料,不仅在机械电子、生物医疗、航空航天领域得到了越来越多的应用,而且在土木工程的研究与应用方兴未艾。目前,形状记忆合金在土木工程领域的研究主要集中在混凝土梁的自检测、自修复,混凝土柱的抗震与加固处理,混凝土结构的阻尼抗震等方向。本文简述了形状记忆合金的发展过程及主要特性;分别介绍了利用形状记忆合金的形状记忆效应特性和超弹性特性制成的形状记忆合金智能混凝土构件或结构的研究与应用进展;指出了影响形状记忆合金智能混凝土结构发展的因素及今后的发展方向。     

互动教学在弹性力学教学中的实践与探讨

"工程弹性力学"是一门具有代表性的理工科专业课,课程具有重要的工程应用价值,同时也具有一定的理论深度.传统的以教师讲授为主的教学方法较为依赖教师的经验技巧,课堂气氛难以充分活跃,学生也容易陷于抽象概念和复杂公式,而对知识脉络的掌握较为欠缺.基于BOPPPS有效教学法,以学生视角作为教学设计的"参考系",开展了"引入、学...     

The ‘Design Procedure’ as a Means of Storing Engineering Knowledge

The author observes that, apart from work done in the area of some expert systems, there has been little discussion of the problems of storing the knowledge used by engineering designers. It is often assumed that this comprises only a knowledge of engineering science in conjunction with a certain inner ‘feel’ for materials and system behaviour. The author argues that the knowledge of how to design is different from these and merits a separate identity, with its own epistemology and philosophy. The idea of the ‘design procedure’ is introduced as the means by which certain engineering design knowledge and skill can be stored, communicated, learned, researched, and given its own history independent of engineering science.     

基于价值链的企业价值创造结构探析

每个企业完成价值创造活动的过程都必然会依附于一定的价值创造结构,不同价值创造结构其价值创造能力的大小是不同的.企业的价值创造结构由一些影响价值创造的因素构成,在价值链模式下,为顾客创造价值成为价值创造活动的最终目的.因此,企业要以顾客价值为立足点,以核心能力构筑和建立相互信任关系为准则,对构成企业价值创造结构的因素进行整合与调整,从而实现其对市场需求的快速反应,进而提高其价值创造的能力.     

国外文科高等教育发展趋势及其对我们的启示

在国外高等教育发展中,面对社会经济政治的变化和高等教育的发展,文科通过自身的分化与综合。由绝对统冶到与理工科并存竞争。再到相互交叉、渗透,一直保持着重要地位。它持久的生命力来自它巨大的社会作用,它在发扬民族优良传统、继承宝贵文化遗产、形成世界观、提高个人修养方面的作用是无可替代的。文科研究直接面向社会现实问题,为决策机构服务。各国的文科教育在专业结构、课程设置等均有突出的特点,对我国教育改革有借鉴意义,     

环境工程实验小型环境舱的研制与实验设计

以培养学生的科学素质和创新能力为理念,自行设计和制作小型多功能环境舱,可用于模拟室内环境变化对空气污染物浓度变化的影响,亦可作为室内空气污染物去除的实验装置。介绍其制作思想、结构和功能,并设计与教学内容相适应的实验。     

平板-异形柱结构设计方法的研究

阐述了平板—异形柱结构的适用范围、结构选型、材料选择、截面尺寸的确定和结构的内力分析方法,在此基础上得出了平板—异形柱结构构件的配筋计算方法和配筋构造要求,以供设计人员参考。     

基于树莓派的智能家居系统设计

为满足人们对智能家居产品需求,基于树莓派设计了智能家居控制系统。综合使用 WiFi、ZigBee技术,以树莓派作为系统核心,组建维护网络并整合数据,提供 Web 服务供用户访问,实现室内环境监测、安防监测、家居控制等智能方案,用户可通过终端进行查询与控制。整个系统比传统的单一系统具有多通讯协议功能,同时成本低廉、集成度高,可满足物联网时代家居环境智能化、个性化要求。     

Globalizing the science curriculum: an undergraduate course on traditional Chinese medicine as a complementary approach to Western medicine

A course has been created to examine the ways in which China and the West have approached human health and medicine. Though fundamentally different, these two systems are complementary in a number of ways. This course is a model for a global science course in an educational initiative that incorporates Asian themes into science and engineering courses. The course is designed around an active-learning platform that has as major components: team research projects, oral presentations, role play, and peer-review. The students investigate concepts of scientific proof, clinical efficacy, and the functional structure of two very different systems of health and medical care.     

Current State of Numerical Simulations and Testing for the Blast and Impact Protection of the Build Civil Engineering Infrastructure

The identification of the critical infrastructure has shown that the build civil engineering infrastructure is almost involved everywhere, even with the IT-infrastructure. Therefore, the passive safety of structures is demanded. Security associations have analysed that most assaults came along with explosion and impact scenarios, which amount in 80% of assaults. Consequently, these are the extraordinary loads the structures have to be planned and designed for. To carry out such an engineering job, the engineer has to be educated in multiple disciplines as physics, material science, continuum mechanics, numerical mechanics, testing, structural engineering and related specific fields as wave propagation etc. In this paper we will concentrate on the subjects of numerical simulation and testing.     

Current State of Numerical Simulations and Testing for the Blast and Impact Protection of the Build Civil Engineering Infrastructure

The identification of the critical infrastructure has shown that the build civil engineering infrastructure is almost involved everywhere, even with the IT-infrastructure. Therefore, the passive safety of structures is demanded. Security associations have analysed that most assaults came along with explosion and impact scenarios, which amount in 80% of assaults. Consequently, these are the extraordinary loads the structures have to be planned and designed for. To carry out such an engineering job, the engineer has to be educated in multiple disciplines as physics, material science , continuum mechanics, numerical mechanics, testing, structural engineering and related specific fields as wave propagation etc. In this paper we will concentrate on the subjects of numerical simulation and testing.     

强震作用下独塔斜拉桥抗震性能分析

以某跨径为110 m的独塔异形斜拉桥为工程背景,通过非线性有限元分析对斜拉桥在强震作用下的地震响应特性及减震措施进行了研究,得出如下结论:相比Lander-amboy波,卓越周期与桥梁固有周期较为接近的Cerro Prieto波能够引起结构较大的地震响应。行波效应能够显著增大工程背景斜拉桥的地震响应,且随着视波速的增大,桥梁的加速度响应明显增大。阻尼系数25 000 kN·s/m为工程背景斜拉桥的最优粘滞阻尼器设计参数,且在塔梁连接处安装该参数粘滞阻尼器后,斜拉桥减震效果显著,尤其能明显减小结构的位移响应。     

关于地下水科学与工程专业本科毕业设计教学模式的改革

为了解决当前地下水科学与工程专业毕业设计中存在的内容片面性和研究方法单一性、专业知识训练体系缺乏系统性、综合性,以及生师人数比过高等问题,充分发挥毕业设计在教学环节中的特殊作用,提出了新的模块式毕业设计运行模式,并给出了新模式的结构、实现方式和评价完善体系的构架。