圆柱—接管拐角裂纹疲劳寿命的估算

压力容器的失效通常发生在接管拐角部位,而失效的原因往往是拐角区裂纹的疲劳扩展。本文研究压力容器接管拐角裂纹前缘形状的变化规律,对裂纹扩展速率作进一步定量计算。实验验证表明,该研究结论是正确的。     

远距离图文传输监控系统

本文介绍了应用于南京市消防指挥中心的远程图文监控系统,该系统使用标准电话线传输动态图象,并获得了较高性能。文中分析了动静态压缩相结合的图象压缩方法,主要为I、B、P帧压缩流程,帧结构和解压缩流程。用户反馈意见表明该系统易用且可靠。     

氨基离子液体/CO_2高温高效吸收式制冷循环研究

本文选用高热稳定性的氨基功能型离子液体3-丙胺基-三丁基鏻甘氨酸盐([aP_(4443)][Gly])水溶液为吸收剂与CO_2组成新型吸收式制冷循环工质对。根据已测定的CO_2在[aP_(4443)][Gly]水溶液中的溶解度,拟合并外延得到300～510 K、1～10 MPa条件下[aP_(4443)][Gly]水溶液中CO_2的溶解度。测定了285～365 K温度范围内不同浓度[aP_(4443)][Gly]水溶液的质量定压热容,计算得到[aP_(4443)][Gly]水溶液的焓。用两种方法分析了[aP_(4443)][Gly]水溶液对CO_2的吸收焓,得到[aP_(4443)][Gly]水溶液/CO_2体系焓。根据以上数据分析计算[aP_(4443)][Gly]水溶液/CO_2单效吸收式制冷性能系数。结果表明:[aP_(4443)][Gly]水溶液/CO_2工质对可以在较高温度环境下工作,在发生温度为393.15 K,蒸发温度为278.15 K,冷却温度为303.15 K时,制冷性能系数可达0.87;在更高的发生温度下,制冷性能系数可达0.91,说明[aP_(4443)][Gly]水溶液/CO_2工质对具有成为新型吸收式制冷工质对的巨大潜力。     

提高工程机械液压系统清洁度

长期以来,工程机械液压系统的清洁度问题一直影响产品质量提高。据国内有关资料统计,工程机械由于液压系统不清洁出现的故障占整机故障率的40%,而由于液压油管内部不清洁造成的故障占液压系统故障率的60%。由此可见,提高液压系统的清洁度对于提高产品质量是何等的重要。 随着国际国内工程机械发展速度的加快,采用高新技术的液压控制元件、动力元件和执行元件越来越普及,相对的要求液压系统清洁度也就越来越严。 影响液压系统清洁度的因素很多,在液压系统中,液压动力元件（液压泵）、执行元件（液压缸）、控制调节元件（各种控制阀）、辅助装置（油箱、滤油器、油管及管接头）的清洁度,都会直接影响到装载机的性能和参数,直接影     

一种改进的疲劳裂纹闭合Newman模型

针对Nweman模型、Dugdale模型存在的对裂纹前端复杂塑性区和变应力比情况的计算精度不高、计算量大的问题，提出了一种改进模型。利用改进模型的计算结果，与Elber的实验结果以及Dugdale的理论分析结果进行了对比，证明了改进模型具有较高的精度。利用改进模型，对各种不同的应力比和过载情况下的裂纹扩展进行了计算，模拟出明显的裂纹闭合现象，其结果有助于裂纹闭合分析理论的建立。     

High Efficient Removal of Trace Molybdenum from Water by FeCl3: Effects of pH and Affecting Factors in the Presence of Co-existing Background Constituents

The effect of FeCl_3 coagulation-filtration on the removal of trace Mo(Ⅵ) from water is investigated in the p H range of 4. 00 to 9. 00 and the effects of sulfate,silicate,phosphate and humic acid( HA) on the process were determined. Overall,the removal of Mo(Ⅵ) is determined by two factors: the content of Fe intercepted from water( Intercepted Fe) and the affinity between Mo(Ⅵ)( or co-existing background constituents) and adsorption sites. At low p H,where the agglomeration of the iron flocs is limited,the former factor is dominant,so the methods that can promote the agglomeration of the iron flocs,such as increasing the p H,adding co-existing constituents( sulfate,phosphate or HA),can increase the removal of Mo(Ⅵ). While at high p H,the second factor dominated. Increasing the p H weakens the affinity between Mo(Ⅵ) and the iron flocs,and co-existing background constituents( sulfate,phosphate,silicate or HA) compete with Mo(Ⅵ) for adsorption sites,both effects result in a decrease in Mo(Ⅵ) removal. The Mo(Ⅵ) removal efficiency of FeCl_3 in natural water decreases as the p H increases from 4. 00 to 9. 00,and it is better to operate the coagulation process at p H 5.00 in the practical water treatment engineering.     

基于新型PID控制器的列车自动驾驶调速系统

基于对列车自动驾驶系统(ATO)的研究,提出了基于重新参数化的B样条神经网络以及粒子群算法的PSO-B-PID控制器;该控制器能通过PSO搜索找到最佳适合的β因子,从而得到适合本网络权值搜索的最佳的重新参数化B样条基函数,同时,文中还提出了由粒子群算法取代传统BP后向传播算法来作为网络学习算法,从而有效克服传统算法易于陷入局部最优的缺点。通过比较实验中建立的PSO-B-PID、BP-B-PID以及PSO-BP-PID 3种控制器的控制性能,结果表明PSO-B-PID控制过程的误差变化最为缓和,其超调量也最小,因此,该控制器能够提高ATO系统控制的快速性、乘坐舒适度以及停车精度。     

On the designing principles and optimization approaches of bio-inspired self-organized network: a survey

A plethora of studies on self-organization has been carried out in broad areas including chemistry, biology, astronomy, medical science, telecommunications, etc., in both academia and industry. Following the studies on swarm intelligence observed in social species, the artificial self-organized systems are expected to exhibit some intelligent features (e.g., flexibility, robustness, decentralized control, self-evolution, etc.) that may have made social species so successful in the biosphere. In this paper, the application of swarm intelligence in communications networks will be studied, and we survey different aspects of bio-inspired mechanisms and examine various algorithms that have been proposed to improve the performance of artificial systems. Some fundamental self-organized networking (SON) mechanisms, designing principles and optimization approaches for artificial systems will then be investigated, followed by some well-known bio-inspired algorithms (e.g., cooperation, division of labor, distributed network synchronization, load balancing, etc.) as well as their applications to the maintenance/operation/optimization of artificial systems being analyzed. Besides, some new emerging technologies, such as the Self-X capabilities and cognitive machine-to-machine (M2M) optimization for the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE)/LTE-Advanced systems, are also surveyed. Finally, the remaining challenges to be faced in designing the future heterogeneous systems will be discussed.     

Effects of Mitigating Fouling on the Energy Efficiency of Crude-Oil Distillation

An analysis was performed to determine the effects of fouling of the preheat train on the energy efficiency of a typical crude-distillation unit with a capacity of 100,000 bbl/day. A spreadsheet analysis was developed to calculate the thermal duty for each of the heat exchanger groups that heat the crude oil from ambient conditions to the distillation temperature. A fouling-rate model developed in a previous study was applied to calculate the fouling resistance as a function of time. Improvements in the energy efficiency were analyzed for different mitigation scenarios. The analysis shows economic incentives for new and improved techniques for mitigating fouling of the preheat train.     

硅藻土保温材料的实验研究

本文对硅藻土保温制品的烧结温度,加温过程,木屑含量与容重、抗压强度的关系进行了实验研究,结果表明:硅藻土保温材料的最佳烧结温度应在780℃左右,木屑含量为30％～33％.木屑粒子直径应是1mm的均匀粒子为好。此外,对国内部分企业如何提高该类制品的质量提出了建议。