钢管混凝土Y形柱非线性有限元分析及试验对比研究

以北京市某地铁车站Y形钢管混凝土柱为工程背景,在对其进行拟静力试验的基础上,利用大型通用有限元软件Abaqus对缩比试验模型进行建模和分析,并将计算模型得到的骨架曲线、柱底应力和应变、Y形铸钢部分应力与试验结果进行对比分析,得到结论:1)模拟计算结果与试验结果基本吻合,有限元模拟有一定的可靠度,可为实际设计及施工提供参考,也可为以后研究提供借鉴。2)根据结果推测,柱底仍是试件最薄弱部位。3)提出扩大模型范围研究,对结构进行设计优化和通过等效简化模型来提高其精确度的展望。     

提高测控技术与仪器专业学生创新能力的探索

测控技术与仪器是一个集光、机、电为一体的宽口径电类专业,不仅涉及的理论知识广泛,而且工程性强,对学生的实践能力要求高.本文介绍了我们在提高测控技术与仪器专业本科生创新实践能力方面所做的一些探索工作,即引导学生开展课外研学,发挥科研优势,吸收本科生参与教师的科学研究,并采用导师制和课题组集体指导方式,提高学生的创新实践能力等.     

采用小波降噪和神经网络的FOG温度漂移补偿方法

光纤陀螺(FOG)输出易受环境温度的影响,发生漂移导致光纤陀螺测量精度降低。采用传统的BP神经网络容易陷入局部极小值,导致网络训练失败。为了优化BP神经网络,本文提出了一种粒子群(PSO)优化BP神经网络与小波降噪相结合的光纤陀螺温度漂移补偿方法。首先分析了光纤陀螺温度漂移产生的原因;然后在不同温度下对光纤陀螺进行测试,最后采用该方法建立了光纤陀螺温度漂移模型并根据模型对光纤陀螺进行补偿,结果表明采用该方法补偿后光纤陀螺在不同温度下的输出标准差降低了60.19%,与传统的BP神经网络相比补偿效果显著提高。     

Time-energy analysis of multilevel parallelism in heterogeneous clusters: the case of EEG classification in BCI tasks

The Journal of Supercomputing - Present heterogeneous architectures interconnect nodes including multiple multi-core microprocessors and accelerators that allow different strategies to accelerate...     

对交互图表系统的案例解析

通过对交互图表系统的解析,向人们展示了一个交互系统实例工作的全过程.交互界面的设计以及功能的实现是设计此系统的关键.并放眼未来,描述了人机交互的未来发展趋势.     

浅析新旧文化式原型

日本的文化式原型由于其科学性和方便性受到服装界人士的广泛认可.1999年日本文化服装学院在旧原型的基础上推出了新一代原型.但由于旧原型已被普遍接受,新原型传入时间短,其合理性未被充分认识因而未得到广泛推广.为了提高服装界人士对新原型的认识,本文对新旧文化式原型的结构原理及造型效果进行了分析和比较,并通过实验进行了验证,结果表明新原型在各个部位的设计更趋向合理,对体型的覆盖率也有了很大程度的提高.     

Modular proofs for key exchange: rigorous optimizations in the Canetti–Krawczyk model

Various optimizations in the Canetti–Krawczyk model for secure protocol design are proven to preserve security. In particular it is shown that multiple authenticators may be safely used together; that certain message components generated by authenticators may be reordered (to be sent at a different time) or replaced with other values with certain precautions; and that protocols may be defined in the ideal world with session identifiers constructed during protocol runs. Consequently protocol designers now have a set of clear rules to optimize and customize their designs without fear of breaking the security proof. In order to obtain the required proofs, we find it necessary to slightly revise the authenticated links part of the Canetti–Krawczyk model. Research funded by Australian Research Council through Discovery Project DP0345775     

Comparison of Gut Bacterial Communities of Grapholita molesta (Lepidoptera: Tortricidae) Reared on Different Host Plants

Intestinal symbiotic bacteria have played an important role in the digestion, immunity detoxification, mating, and reproduction of insects during long-term coevolution. The oriental fruit moth, Grapholita molesta, is an important fruit tree pest worldwide. However, the composition of the G. molesta microbial community, especially of the gut microbiome, remains unclear. To explore the differences of gut microbiota of G. molesta when reared on different host plants, we determined the gut bacterial structure when G. molesta was transferred from an artificial diet to different host plants (apples, peaches, nectarines, crisp pears, plums, peach shoots) by amplicon sequencing technology. The results showed that Proteobacteria and Firmicutes are dominant in the gut microbiota of G. molesta. Plum-feeding G. molesta had the highest richness and diversity of gut microbiota, while apple-feeding G. molesta had the lowest. PCoA and PERMANOVA analysis revealed that there were significant differences in the gut microbiota structure of G. molesta on different diets. PICRUSt2 analysis indicated that most of the functional prediction pathways were concentrated in metabolic and cellular processes. Our results confirmed that gut bacterial communities of G. molesta can be influenced by host diets and may play an important role in host adaptation.     

基于Pro／E＋VC＋ADO＋Access的角钢参数化设计

以VC＋＋6.0为开发工具, Access 2003为数据库管理系统,采用ADO数据库访问技术,在Pro/E环境下实现了采用ADO接口技术访问Access ,以等边角钢参数化设计为例,介绍了其实现过程。     

Genetic algorithm to design logical topologies in reconfigurable WDM networks

A new method to design logical topologies based on genetic algorithms is presented. Not only does the algorithm determine which nodes should be connected by means of lightpaths with the aim of minimizing congestion, but it also solves the routing and wavelength assignment problem. In this way, the algorithm guarantees that the logical topology obtained can be embedded in the optical network subject to the available set of resources. The algorithm is effective in terms of both congestion and fairness. For instance, when compared with other work, the congestion is significantly reduced (from 20% to 75% depending on the matrix of traffic considered), and the fairness, when evaluated in terms of the Jain index, is generally higher than 0.94. Moreover, the algorithm brings advantages when employed in dynamic scenarios where the logical topology is frequently reconfigured, as it is fast and, in contrast to other algorithms previously proposed, the calculation process can be stopped at any time (if required) in order to give the best virtual topology found up to the moment.