铁素体-奥氏体异种钢接头的界面组织及力学性能

为提高电站锅炉过热器铁素体－奥氏体异种钢焊接接头的高温蠕变断裂强度和服役寿命，设计了专用的镍基填充材料及组合焊接接头。通过对不同焊缝接头的高温蠕变力不试验，焊缝界面组织变化分析，碳扩散和热应力的测试分析，认为在高温低力的条件下，接头焊缝界面及热影响区碳元素扩散迁移和碳化物聚集是影响接头蠕变断裂强度的重要原因。     

ANALYSIS ON THE BEHAVIOR OF PRECIPITATES IN ULTRA-THIN HOT STRIP OF PLAIN LOW CARBON STEEL PRODUCED BY COMPACT STRIP PRODUCTION

This paper investigated the mechanism of precipitation and its influence upon prop-erties of ultra-thin hot strips of low carbon steel produced by CSP techniques using experiment and thermodynamics theory. The experimental results show that there are lots of fine and dispersive precipitates in microstructures. By analysis, most of aluminum nitrides are in grains, while coexisted precipitates of MnS are along grain boundaries. Coexisted precipitates compose cation-vacancy type oxides such as Al2O3 in the core, while MnS is at the fringe of surface. The precipitation behavior of AlN and MnS in the hot strip is studied by thermodynamic calculation. At last, implica-tions between strengthening effect and techniques are analyzed using obtained solubility products.     

空气预热器密封片失效原因分析及建议

通过宏观分析、理化检验、扫描电镜观察及能谱成分分析，对燃油电厂空气预热器密封片的失效原因进行分析。结果表明:空气预热器密封片出现规律性破损，是由低温硫酸露点腐蚀、密封片刮擦及吹灰蒸汽带水共同作用导致，其中又以吹灰蒸汽带水作用为甚。建议通过提高吹灰蒸汽过热度以及延长疏水时间，来提高吹灰蒸汽品质，进而达到减缓密封片损坏的目的。     

水工钢闸门使用年限对其结构安全的影响分析

随着使用年限的逐渐延长,水工钢闸门会出现锈蚀、磨损、空蚀、裂纹、变形、连接件松动、活动关节咬死等各种各样的缺陷。在对腐蚀削弱后的断面进行强度复核时,不宜采用使用年限折减的方式修正结构材料的容许应力。     

一种高精度车载坡度检测仪的研制

针对现有车载坡度检测技术缺陷,提出了一种高精度车载道路坡度检测仪的设计及实现方案。该检测仪由主控节点和多个检测节点组成,检测节点通过三轴加速度传感器检测与地面倾角,并将其发送给主控节点;主控节点收集各检测节点数据,对其进行数据融合得到坡度的最优估计值。通过仿真和实验验证了方案的可行性,设计成果可广泛应用于车载导航系统中。     

融合张角拥挤控制策略的高维多目标优化

对于高维多目标优化问题,随着目标维数的增加,种群中非被支配解的比例剧增, 严重降低了种群的进化压力.为了对数量众多的非被支配解进行有效的拥挤控制并提升种群的多样性, 本文在提出张角概念的基础上设计了一种新的拥挤控制策略(Congestion control strategy based on open angle, CCSOA),它的时间复杂度并不会随着目标维数的增加而增大. 与目前优秀的进化多目标优化(Evolutionary multiobjective optimization, EMO)算法IBEA (Indicator-based evolutionary algorithm)、NSGAIII (Nondominated sorting genetic algorithm III)和GrEA (Grid-based evolutionary algorithm)的比较结果表明, 融合了CCSOA的高维多目标优化算法在收敛效果和解集分布的均匀性两个方面均有较大的优势.     

Model checking dynamic pushdown networks

A dynamic pushdown network (DPN) is a set of pushdown systems (PDSs) where each process can dynamically create new instances of PDSs. DPNs are a natural model of multi-threaded programs with (possibly recursive) procedure calls and thread creation. Thus, it is important to have model checking algorithms for DPNs. We consider in this work model checking DPNs against single-indexed LTL and CTL properties of the form \({\bigwedge f_i}\) such that f _i is a LTL/CTL formula over the PDS i. We consider the model checking problems w.r.t. simple valuations (i.e., whether a configuration satisfies an atomic proposition depends only on its control location) and w.r.t. regular valuations (i.e., the set of the configurations satisfying an atomic proposition is a regular set of configurations). We show that these model checking problems are decidable. We propose automata-based approaches for computing the set of configurations of a DPN that satisfy the corresponding single-indexed LTL/CTL formula.     

多社区网络上的命名博弈

为了模仿人类对新物体认知和命名的过程,提出了一种新型的命名博弈模型,它通过词汇的权重表示个体的认知程度,低权重词汇被删除模拟个体有限记忆的过程.实验发现,在单社区网络上,所有个体的词汇最终能够统一,通过总词汇数、不同词汇数和平均协议成功率的分析解释了新个体命名的演化过程.衰减因子和删除阈值的取值对于演化速度影响较大,当它们之间存在线性关系时演化收敛较快.通过将该模型应用到多社区网络模型上,发现收敛词汇数可能不唯一,会与社区数相同,且收敛词汇数的稳定性与网络社区化强度和社区内节点的平均度有关,而与社区内节点数无关.最后,使用微分动力学的方法对这种情况进行了定量分析.     

Finding logos in real-world images with point-context representation-based region search

Finding logos in the real-world images is a challenging task due to their small size, simple shape, less texture and clutter background. In this paper, through visual logo analysis with different types of features, we propose a novel framework for finding visual logos in the real-world images. First, we exploit the contextual shape and patch information around feature points, merge them into a combined feature representation (point-context). Considering the characteristics of logos, this kind of fusion is an effective enhancement for the discriminability of single point features. Second, to eliminate the interference of the complex and noisy background, we transfer the logo recognition to a region-to-image search problem by segmenting real-world images into region trees. A weak geometric constraint based on regions is encoded into an inverted file structure to accelerate the search process. Third, we apply global features to refine initial results in the re-ranking stage. Finally, we combine each region score both in max-response and accumulate-response mode to obtain the final results. Performances of the proposed approach are evaluated on both our CASIA-LOGO dataset and the standard Flickr logos 27 dataset. Experiments and comparisons show that our approach is superior to the state-of-the-art approaches.