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41.
曲率模态是结构损伤识别的敏感标示量,采用数值仿真方法,把曲率模态用于桥梁损伤识别.利用简支梁损伤前后一阶曲率变化率作为识别参数,便可明显确定其多处损伤位置.对相关样本参数进行归一化处理并引入噪声干扰,利用BP人工神经网络进行数值仿真计算,也能对其损伤程度进行有效模拟,验证了BP神经网络也有很强的泛化能力及容错能力. 相似文献
42.
对在CSY型传感器综合实验仪上拓展悬臂梁力学实验进行了研究,研究了在该实验仪上实现材料弹性模量的测定.通过材料力学的理论推导出悬臂梁弹性模量与其受力和挠度比值的关系,通过应变式传感器的实验确定出悬臂梁受力与其挠度的比值关系,进一步可推导出悬臂梁材料的弹性模量,并验证了该方法的可行性及有效性.该方法集合了电阻应变效应、全桥差动电路等传感器电测技术以及材料弹性力学、悬臂梁结构力学的基础知识,具有综合应用性.同时,对高校实验室如何有效利用设备资源、开发拓展型实验有一定的示范作用. 相似文献
43.
基于RFID技术的仓库综合管理系统 总被引:1,自引:0,他引:1
为保证大型物流企业仓库的安全,提高仓储效率,提出了一种基于RFID技术构建综合仓库管理系统的思路与方法.系统具有报警功能,可对货物自动进行存储统计.介绍了系统的结构、模块的功能、硬件设计以及软件设计的系统流程,阐述了基于动态二进制的系统防碰撞算法. 相似文献
44.
基于光纤色散引起的脉冲展宽效应,在理论和实验上研究了有源光学电流传感器(AOCS)中宽带光源对系统输出的影响.理论结果表明:对于长度为500m的光纤,当光源谱宽在40—60nm之间变化时,多模光纤传输下的脉冲展宽范围在0.5~0.8ns,单模光纤传输下的脉冲展宽范围在2×10^-5~4×10^-5,信号衰减量对系统输出影响很小,且随光源谱宽的增加而有微弱的增加,实验与理论相符合. 相似文献
45.
Yuan-Chih Yu 《中国科学:信息科学(英文版)》2014,57(3):1-10
As the use of smartphones become popular,people heavily depend on smartphone applications to deal with their social activities.For this reason,traditional message texting between mobile applications does not fulfill the versatile requirements of social networking.Many mobile applications use multimodality to deliver multimedia messages including sticker,voice and photo message,video call,and snap movie to enhance the communicative capability.However,without face-to-face interaction,people may fail to detect the other side’s non-verbal social behavior such as fine-grain facial expressions,body movements,or hand gesture.During social interaction,non-verbal behavior conveys information about the involved individuals and help the speakers express their social emotion in an implicit way.It is so important for real-world face-to-face interaction but is often blocked on the mobile telephony.To cope with this problem,we propose an afective computing model to assist the representation of social emotion and then help the progress of social interaction on the mobile telephony.In this model,for the purpose of real-time afective analysis,we delegate the computing loading to the cloud side service and enhance the system’s scalability and availability.The result of this experiment approves the feasibility of our system design for the applications of social intelligent.Also,the system provides a research framework of the social intelligent system on the mobile telephony. 相似文献
46.
Caroline Cannizzo 《Polymer》2005,46(4):1269-1276
Translucent boronic acid-carrying nanolatexes are prepared by copolymerisation of vinylbenzyl chloride in microemulsion followed by post functionalisation with 3-aminophenylboronic acid. The diol binding capacity and selectivity of the phenylboronic acid remain unchanged after anchoring to polymer nanoparticles (16 nm diameter, 0.22 mmol/g). The binding of a catechol dye, Alizarin Red S (ARS), to the boronic acid-carrying nanoparticles affords a colored, stable, nanolatex which is used for the selective visual detection of fructose in a competitive assay. The binding of fructose at pH 8.2 is readily evidenced by a color change and monitored by UV/Vis spectroscopy. The nanosensor can be regenerated in acidic medium. The entrapment of the nanolatex in a dialysis cell provides a re-usable support for binding and optical detection. 相似文献
47.
Xiangmao MENG Wenkai LI Xiaoqing PENG Yaohang LI Min LI 《Frontiers of Computer Science》2021,15(6):156902
In the post-genomic era, proteomics has achieved significant theoretical and practical advances with the development of high-throughput technologies. Especially the rapid accumulation of protein-protein interactions (PPIs) provides a foundation for constructing protein interaction networks (PINs), which can furnish a new perspective for understanding cellular organizations, processes, and functions at network level. In this paper, we present a comprehensive survey on three main characteristics of PINs: centrality, modularity, and dynamics. 1) Different centrality measures, which are used to calculate the importance of proteins, are summarized based on the structural characteristics of PINs or on the basis of its integrated biological information; 2) Different modularity definitions and various clustering algorithms for predicting protein complexes or identifying functional modules are introduced; 3) The dynamics of proteins, PPIs and sub-networks are discussed, respectively. Finally, the main applications of PINs in the complex diseases are reviewed, and the challenges and future research directions are also discussed. 相似文献
48.
Device-to-Device (D2D) communication can reduce the mobile devices' energy consumption and increase the spectral efficiency in D2D underlaid cellular networks. However, D2D users will interfere with co-channel cellular users, which can lead to cellular communication access failures. There are two reasons for cellular communication access failures: (1)D2D interference and (2)insufficient spectrum resources. To address the absence of research on the performance of cellular services' access in D2D underlaid cellular networks, this paper defines the new services' access failure probability and handoff services' access failure probability to evaluate the effect of both D2D interference and limited resources on cellular communication access. Based on the stochastic geometry and stochastic process, a random network model is presented to estimate the access failure probabilities, which can provide guidelines for network design to ensure cellular services' access. The accuracy of the estimated access failure probability is validated through extensive simulations. 相似文献
49.
邵林 《安徽冶金科技职业学院学报》2017,27(1)
为了能够准确地测量污水旋流池的液面高度,设计了基于超声传感技术的污水旋流池液面测量方法,通过长时间的运行,测量数据完全满足污水旋流池的生产工艺要求。 相似文献
50.
通过鱼骨图的方法对现有智能公交投币机存在识别率偏低的问题进行了分析,提出在智能投币机中采用闭式五角叶轮或增加硬币预处理部分,对现有的智能公交投币机进行改进,使智能公交投币机的硬币辨识率得到提高. 相似文献