Influence of minor boron on the microstructures of a second generation Nibased single crystal superalloy

Boron is added into single crystal superalloys as a micro-alloying element to strengthen low angle grain boundaries.However,systematic investigations on the effect of boron on microstructures of single crystal superalloys are limitedly reported.The effect of boron on as-cast and heat-treated microstructures was investigated in two experimental Ni-based single crystal superalloys containing 3 wt% Re.The current results indicated that the volume fraction of(γ+γ′)eutectic and M_3B_2 borides was evidently increased,while the number of micropores was evidently decreased with the addition of 0.02 wt% boron.The(γ+γ′)eutectic could not be dissolved completely due to the lower incipient melting temperature caused by the formation of M_3B_2 borides.Meanwhile,the M_3B_2 borides were found to be enriched with indispensable strengthening elements Cr,Mo,W and Re,and this may lower the strengthening effect and cause stress concentration during high temperature creep.     

System deployment optimization in architecture design

Optimization of architecture design has recently drawn research interest. System deployment optimization （SDO） refers to the process of optimizing systems that are being deployed to activi- ties. This paper first formulates a mathematical model to theorize and operationalize the SDO problem and then identifies optimal so- lutions to solve the SDO problem. In the solutions, the success rate of the combat task is maximized, whereas the execution time of the task and the cost of changes in the system structure are mini- mized. The presented optimized algorithm generates an optimal solution without the need to check the entire search space. A novel method is finally proposed based on the combination of heuristic method and genetic algorithm （HGA）, as well as the combination of heuristic method and particle swarm optimization （HPSO）. Experi- ment results show that the HPSO method generates solutions faster than particle swarm optimization （PSO） and genetic algo- rithm （GA） in terms of execution time and performs more efficiently than the heuristic method in terms of determining the best solution.     

李渔从绘画到戏曲的身份认同

李渔是中国古代著名的文化艺术大家,毕生直面社会经济发展潮流,绘画理论与实践根置现实,执着无待而兴;与此同时,通过实施直观实用的创作原则,绘画向戏曲渗透,艺术向谋生齐观,获得了戏曲上的独特建树,充分体现了李渔从绘画到戏曲的身份认同,以及商品经济价值取向。李渔从绘画到戏曲具有强烈的商品经济意识与动机,所含审美理想与经济实用兼而有之,给予当今人们有益的启迪。     

浅谈隧道锚喷混凝土的施工技术

公路隧道锚喷支护是将锚杆与喷射混凝土作为加强和利用围岩自身支撑能力,文章结合多次隧道施工、实践经验,介绍了常用锚杆的安设、喷射混凝土作业过程及喷枪头施工操作注意事项。     

Upper bounds of differential characteristic probability for unbalanced Feistel network employing DSM

In this paper, for the unbalanced Feistel network which employs diffusion matrices in a switching way, we study the fixed number of its differential active S-boxes. Firstly we obtain some lower bounds of the differential active S-boxes for m, 2m and 3m rounds of Feistel structure, respectively. By concatenating these rounds, a fixed number of differential active S-boxes for arbitrary round number is derived. Our results imply that the unbalanced Feistel network using DSM is more secure than the traditional structure.     

Ho∞-based fault detection for nonlinear networked systems with random packet dropout and probabilistic interval delay

The fault detection problem for the nonlinear networked control system (NCS) with packet dropout and delay is investigated.A nonlinear stochastic system model is proposed to account for the NCS with random packet dropout and networkinduced non-uniformly distributed time-varying delay in both from sensor to controller (S/C) and from controller to actuator (C/A).Based on the obtained NCS model,employing an observer-based fault detection filter as the residual generator,the addressed fault detection problem is converted into an auxiliary nonlinear H∞ control problem.Then,with the help of Lyapunov functional approach,a sufficient condition for the desired fault detection filter is constructed in terms of certain linear matrix inequalities,which depend on not only the delay interval but also the delay interval occurrence rate and successful packet communication rate.Especially,a trade-off phenomenon between the maximum allowable delay bound and successful data packet transmission rate is found,which is typically resulted from the limited bandwidth of communication networks.The effectiveness of the proposed method is demonstrated by a simulation example.     

论美国保险法合理期待原则的产生与新发展

合理期待原则是美国保险法为规范保险合同最新发展的原则,该原则针对的是保险合同订立中不利于投保人、被保险人的特点而提出,该原则最新的发展动向是法院在适用中与第二次《合同法重述》关于格式合同的适用例外规定相结合,为我国保护保险消费者提供了新的思路。     

Attentional negativity bias moderated by positive mood arousal

Automatically allocation of more attention to negative stimuli is called emotional negativity bias. An event-related potentials (ERPs) experiment investigated whether or not this bias was altered by positive mood arousal. The results suggested that the attention bias towards negative stimuli was attenuated when positive information was accessible.     

X80级管线钢的开发研究

根据X80级管线钢技术要求,对湘潭钢铁(集团)有限公司试制X80级管线钢进行成分设计、相变规律和再结晶规律研究,开发出了1 016×22.0 mm X80级热轧钢板.检验结果表明,各项性能指标均满足技术要求.