人工神经网络预测热油环道启动压力

高含蜡原油管道停输后的再启动问题非常复杂。它涉及因素多，问题的非线性很强。而有足够多神经元的S型三层神经网络理论上可逼近任意有理函数。文章采用误差反向传播网络预测环道实验装置中的启动压力，得到了较好结果。     

A novel optical burst switching scheme—logical cascaded private subnet with start wavelength assignment policy

Many recent studies have convincingly demonstrated that network traffic exhibits a noticeable self-similar nature, which has a considerable impact on network performance, and most studies of optical burst switching (OBS) networks are under a fundamental assumption that full wavelength conversion is available throughout the network. In practice, however, economic and technical considerations are likely to dictate a more limited and sparse deployment of wavelength converters in the optical network. Therefore, we present a novel scheme for OBS networks, called logical cascaded private subnet (LCPN) with start wavelength assignment policy. We define the concept of canoe relative to cluster in self-similar traffic, and introduce a new device named payload segregator at the edge node as a gateway to the core node in OBS Networks. According to the changes in the edge node framework, we put forward the concept of cluster private subnet and canoe private subnet in the core node correspondingly. A new start wavelength assignment policy is proposed for the absence of (full) wavelength conversion capabilities in the core node of OBS Networks. The performance study indicates that, our new scheme is robust under self-similar traffic and wavelength continuity constraint.     

TCP协议在卫星网络中的问题研究

由于TCP协议直接应用到卫星网络中将可能会导致网络性能下降,因此针对卫星网络的特点,分析了传播时延、高误码率、非对称连接方式等特点对TCP协议性能的影响,对主要解决方法进行了分析、比较现有的几种解决方法利弊,应根据具体应用采用相应的解决方案。     

燃料电池发动机冷启动进气预热系统性能研究

为了分析冷启动过程中质子交换膜燃料电池发动机的空气加热系统的工作性能,采用ε-NTU方法和CFD仿真技术得到了双流程换热器内部的温度分布,研究了冷却液温度和流量对整体散热器的换热性能的影响。通过比较发现模拟值与测试数据的误差小于10%,表明仿真模型和采用多孔介质模型的研究方法的可行性。根据仿真结果,采用遗传算法得到了该系统采用的铝制散热器的冷却液的最优参数组合,研究结果为优化空气预热系统,提高散热器的冷却效率提供了指导。     

鼠笼式异步电动机电液变阻软起动技术的研究与应用

介绍了在鼠笼式异步电动机上应用的电液变阻软起动装置的原理及性能特点，通过实践证明了电液变阻软起动技术不仅改善了电动机起动电流大对电网和设备造成的冲击，能使起动电流控制在电动机额定电流的2.5倍以内，而且起动过程中由于电液变阻装置的电阻值随电机负荷的增大而均匀减小，从而使电机具有平滑的起动性能。     

灯泡式贯流泵站机组起动过渡过程仿真计算

为掌握大型贯流泵站同步电动机起动过程中水泵动态流量、装置扬程等水力量及同步电动机的起动电压、起动电流、机组转速等电气量、机械量参数随机组起动历时的变化过程，对贯流泵机组起动过程进行了详细的理论分析并进行了仿真计算。从泵系统整体出发，运用刚体动力学、流体动力学、水力机械全特性理论，分析泵机组系统起动过程中同步电动机的电磁驱动力矩、水阻力矩及其它各种阻力矩动力学特性，建立了大型贯流泵站起动动态过程数学模型，以淮安三站贯流泵为算例，通过仿真计算，揭示大型贯流泵泵站起动过渡过程中各种重要参数如转速、流量、扬程、转矩等随时间变化关系，研究成果对贯流泵站合理设计和安全可靠运行具有重要理论指导意义。     

The Effectiveness of Early Head Start for 3-Year-Old Children and Their Parents: Lessons for Policy and Programs.

Early Head Start, a federal program begun in 1995 for low-income pregnant women and families with infants and toddlers, was evaluated through a randomized trial of 3,001 families in 17 programs. Interviews with primary caregivers, child assessments, and observations of parent-child interactions were completed when children were 3 years old. Caregivers were diverse in race-ethnicity, language, and other characteristics. Regression-adjusted impact analyses showed that 3-year-old program children performed better than did control children in cognitive and language development, displayed higher emotional engagement of the parent and sustained attention with play objects, and were lower in aggressive behavior. Compared with controls, Early Head Start parents were more emotionally supportive, provided more language and learning stimulation, read to their children more, and spanked less. The strongest and most numerous impacts were for programs that offered a mix of home-visiting and center-based services and that fully implemented the performance standards early. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

交换机LS中继全自动维护的实现

环路启动(LS)中继在电力专网中使用非常广泛,人工恢复长时间不拆线的LS中继的维护方式已经不能满足需求,故利用开发工具(Delphi)编写软件实现和交换机通信,自动检测所有LS中继线的状态,自动恢复长时间处于维护忙状态的LS中继。文章介绍了该系统的实现过程及系统中各模块的功能。该系统的实现提高了工作效率,保障了交换网的通信质量。     

为应用程序制作启动封面的几种方法

介绍为应用程序制作启动封面的四种方法.     

The polytropic volume method to detect engine events based on the measured cylinder pressure

Internal combustion engines deliver work using an intermittent thermodynamic process. For control and diagnosis purposes, it is useful to detect key events relative to the crank angle position. A new method to detect the intake valve closing (IVC), start of combustion (SOC), end of combustion (EOC) or exhaust valve opening (EVO), using the measured cylinder pressure as input, is described. The method is based on the observation that the compression and expansion processes are of polytropic nature. It is shown that the events can be detected by detecting the points where the real and the polytropic volume diverge.