The influence of fiber type and conformation on the damping property of FRP composite

In order to get a fiber reinforced plastic(FRP) composite with good damping property as well as good mechanical properties, different types of reinforcing materials were used to reinforcing a damping resin. The influence of fiber types and conformation on the damping property of the composite are tested. Compared to the glass fiber(GF), carbon fiber(CF) can improve the damping factor of the composites; the highest tanδ value is 0.827 while the Tg is 22.5 ℃. The style of the fibers also influences the damping factors of the composite. The composite reinforced with mat has higher loss factors than that composite reinforced with clothe for the reason that the former has the ability to deform and the composite has higher resin content. The loss factor of GF mat reinforced composite is 0.704 while the Tg is 27 ℃. Both composite has good damping properties and can be used as the damping layer of the structural damping composite.     

混凝土结构空间多尺度相对湿度值

针对环境作用具有空间分布特性,借鉴空间多尺度环境作用模型框架（包括全局环境、地区环境、工程环境、构件表面环境、内部环境）及其数学模型,对相对湿度进行了空间多尺度研究：在分析空间各尺度上相对湿度的不同影响因素的基础上,由全局环境尺度开始,通过地区环境尺度、工程环境尺度以及构件表面环境尺度上环境因素的逐步调整,最终计算得到混凝土内部的相对湿度值。研究结果表明,采用＂常规统计模型＋空间残差＂的方法,可有效建立地区环境尺度上的相对湿度值与工程环境尺度上相对湿度值的定量关系;混凝土结构构件的表面相对湿度与表面温度有关;实际工程结构应考虑构件表面相对湿度与内部相对湿度之间的不同。     

Physicochemical properties and heavy metals leachability of fly ash from coal-fired power plant

The physicochemical properties of fly ash from two kinds of coal-fired power plants were studied. Three aspects were examined: the micro-morphology, the mineral composition and the content of heavy metals. The results show that the fly ash from plants using a circulating fluidized bed are more irregular particles, while the particles from the plants using a pulverized coal-fired boiler are mainly spherical in shape. Quartz and mullite are the main crystalline phases in the ash. Clearly, both the technology and the coal used by a power plant can influence the mineral composition of the ash. The mineral composition of fly ash from a circulating fluidized bed is more complex than that from a pulverized coal-fired boiler. The quantity of elements found in the fly ash is greater than that found in the bottom ash for the same plant. Heavy metals are likely to be enriched in the fly ash. Heavy metal leachability was studied using two leaching methods. The results indicate that most of the heavy metals that leached during either batch leaching or column leaching experiments did not exceed the related maximum concentration standards. But Ni concentrations in the leachates from both batch and column tests exceed the standard. The highest excess rates in both tests were 572% and 497%, which levels might threaten the environment.     

水库水沙优化调度

摘 要:针对水沙优化调度多目标、高维和难以求解的特点,利用约束法将多目标模型转化为单目标模型,并采用全局搜索能力和收敛性较强的鲶鱼效应粒子群算法求解水沙优化调度模型.该算法利用鲶鱼效应对种群多样性的动态调节和驱赶作用,克服了粒子群容易陷入局部最优的缺点.实例验证表明,优化结果给出了较为满意的水库发电与泥沙淤积的非劣解集及水库非劣运用过程,算法具有有效性和通用性.     

白莲河抽水蓄能电站球阀密封损坏原因分析与处理

湖北白莲河抽水蓄能电站主进水球阀在调试过程中先后发生了1号球阀上游密封及2号球阀下游密封损坏事件。通过分析球阀密封结构及原理,剖析了导致球阀密封损坏原因,提出了如何在安装及运行阶段避免类似事件发生的防范措施。两年来的实际运行表明对密封损坏的处理是成功的,对同类电站尤其是设备调试阶段如何避免类似问题有一定的借鉴意义。     

Facial expression recognition using radial encoding of local Gabor features and classifier synthesis

Primarily motivated by some characteristics of the human visual cortex (HVC), we propose a new facial expression recognition scheme, involving a statistical synthesis of hierarchical classifiers. In this scheme, the input images of the database are first subjected to local, multi-scale Gabor-filter operations, and then the resulting Gabor decompositions are encoded using radial grids, imitating the topographical map-structure of the HVC. The codes are fed to local classifiers to produce global features, representing facial expressions. Experimental results show that such a hybrid combination of the HVC structure with a hierarchical classifier significantly improves expression recognition accuracy when applied to wide-ranging databases in comparison with the results in the literature. Furthermore, the proposed system is not only robust to corrupted data and missing information, but can also be generalized to cross-database expression recognition.     

基于混沌PSO算法的Hadoop配置优化

针对Hadoop的组合优化问题,提出一种基于混沌粒子群优化算法的配置优化策略。为保证算法在进行局部搜索的同时避免陷入局部最优,对陷入局部最优的标准值和混沌处理的迭代次数的不同组合进行实验,获得使Hadoop性能达到最优的配置。实验结果表明,算法得出的最优配置方案能够有效提高Hadoop的性能,具有较好的稳定性。     

PVA纤维混凝土受弯梁力学性能分析

研究了PVA纤维混凝土改性梁的抗弯性能,通过对不同配筋率和不同PVA纤维体积掺量的混凝土受弯梁的试验测试,研究混凝土中加入PVA纤维后的增强与增韧作用效果.结果表明:PVA纤维能有效提高混凝土梁的初裂荷载和极限承载力,PVA纤维的掺入使混凝土由脆性破坏变为延性破坏,明显改善了混凝土变形能力.     

MSMSE-based optimal beamforming design and simplification on AF MIMO two-way relay channels

An optimal cooperative beamforming for the amplify-and-forward (AF) MIMO two-way relay channels was designed. Supposing the channel state information (CSI) was perfectly known by the receiver and transmitter as well as the relay, optimal beamforming vectors (matrices) of all nodes were jointly designed based on the criterion of minimizing the sum mean square errors (MSMSE). The analysis result shows that the performance effect of transmitting and receiving beamforming pairs is to maximize the receive signal-to-noise ratio (SNR) at two communication nodes, and the rank of the optimal relay beamforming matrix is no larger than two when there is only one data stream at each source node. A simplified algorithm was put forward to accomplish the design based on the analysis conclusions. Simulation results provide that the system performance, which is characterized in terms of bit error rates (BER), is significantly improved by cooperative beamforming, and the performance of the simplified method is not only very close to the optimal one but also with faster iteration speed and much lower computational complexity.