最小化拖期任务数并行机调度问题的一种基于知识的遗传算法

本文研究了最小化拖期任务数并行调度问题,提出了一种基于知识的遗传算法,并在问题的描述、遗传算法编码、初始种群的产生办法、交叉方法、变异方法等方面作了研究,不同规模问题的数值计算结果表明了本文提出的基于知识的遗传算法优于目前为止最好的启发式算法和普通的遗传算法,并且能适应于较大规模的并行机调度问题。     

Lignin as a Wood‐Inspired Binder Enabled Strong,Water Stable,and Biodegradable Paper for Plastic Replacement

Plastic waste has been increasingly transferred from land into the ocean and has accumulated within the food chain, causing a great threat to the environment and human health, indicating that fabricating an eco‐friendly and biodegradable replacement is urgent. Paper made of cellulose is attractive in terms of its favorable biodegradability, resource abundance, large manufacturing scale, and low material cost, but is usually hindered by its inferior stability against water and poor mechanical strength for plastic replacement. Here, inspired by the reinforcement principle of cellulose and lignin in natural wood, a strong and hydrostable cellulosic material is developed by integrating lignin into the cellulose. Lignin as a reinforced matrix is incorporated to the cellulose fiber scaffold by successive infiltration and mechanical hot‐pressing treatments. The resulting lignin‐cellulose composite exhibits an outstanding isotropic tensile strength of 200 MPa, which is significantly higher than that of conventional cellulose paper (40 MPa) and some commercial petroleum‐based plastics. Additionally, the composite demonstrates a superior wet strength of 50 MPa. Adding lignin also improves the thermostability and UV‐blocking performance of cellulose paper. The demonstrated lignin‐cellulose composite is biodegradable and eco‐friendly with both components from natural wood, which represents a promising alternative that can potentially replace the nonbiodegradable plastics.     

Self‐Healing,Flexible, and Tailorable Triboelectric Nanogenerators for Self‐Powered Sensors based on Thermal Effect of Infrared Radiation

Self‐healing triboelectric nanogenerators (TENGs) with flexibility, robustness, and conformability are highly desirable for promising flexible and wearable devices, which can serve as a durable, stable, and renewable power supply, as well as a self‐powered sensor. Herein, an entirely self‐healing, flexible, and tailorable TENG is designed as a wearable sensor to monitor human motion, with infrared radiation from skin to promote self‐healing after being broken based on thermal effect of infrared radiation. Human skin is a natural infrared radiation emitter, providing favorable conditions for the device to function efficiently. The reversible imine bonds and quadruple hydrogen bonding (UPy) moieties are introduced into polymer networks to construct self‐healable electrification layer. UPy‐functionalized multiwalled carbon nanotubes are further incorporated into healable polymer to obtain conductive nanocomposite. Driven by the dynamic bonds, the designed and synthesized materials show excellent intrinsic self‐healing and shape‐tailorable features. Moreover, there is a robust interface bonding in the TENG devices due to the similar healable networks between electrification layer and electrode. The output electric performances of the self‐healable TENG devices can almost restore their original state when the damage of the devices occurs. This work presents a novel strategy for flexible devices, contributing to future sustainable energy and wearable electronics.     

基于等离子体镜的太赫兹单脉冲选择方法

研究了一种用于中国工程物理研究院太赫兹自由电子激光装置(CTFEL)输出的太赫兹的单脉冲选择方法,以满足一些对太赫兹脉冲的时间分辨率和峰值强度提出较高要求同时要保证较低平均功率的实验的需要。利用自诱导等离子体开关技术,太赫兹能够被短脉冲激光打靶产生的等离子体镜反射,从而使等离子体镜可以作为门控开关,选出单个太赫兹微脉冲。通过理论分析计算出等离子体临界密度和激光功率密度阈值,采用辐射流体模拟软件对激光打靶过程进行数值模拟。模拟结果表明,激光激发出的等离子体密度远大于临界密度。由此证明了实验的可行性,进而给出实验所需装置的参数指标以及实验光路设计。     

一种新的含噪混沌信号降噪算法

该文针对低信噪比、非高斯加性噪声和混沌动力学系统参数未知的含噪混沌信号降噪问题,提出了一种基于粒子滤波(Particle Filtering, PF)的降噪新算法。该算法将混沌信号和动力学系统中的未知参数作为一个多维状态矢量,利用PF方法递推计算多维状态矢量的联合后验概率分布,进而实现了对混沌信号的最优估计。对于混沌信号轨道分离过快所导致的退化问题,提出了有效的解决方法,并利用核平滑和自回归(Auto-Regression, AR)模型建模的方法分别实现了非时变以及时变参数的递推估计。仿真实验的结果表明,与现有的降噪方法相比,该文提出的新算法能够更加有效地抑制含噪混沌信号中的加性噪声。     

存在设备时间限制的两个企业协同的综合调度算法

针对自有加工企业设备使用时间存在限制无法满足产品交货期的综合调度问题,该文提出存在设备时间限制的两个企业协同的综合调度算法。为了保证自有加工企业能够获得更多的收益,需要将加工任务尽可能多地分配给自有加工企业进行加工。因此,需要将加工任务进行有效分解,首先逆向遍历加工树,将自有加工企业设备使用时间上限作为阈值,设计加工任务分配策略对加工树进行拆分并生成自有加工企业加工的拆分加工树,其余部分为协同加工企业加工的协同加工树。然后设计协同选择策略,在考虑到运输问题并满足交货期的前提下,选取使自有加工企业收益最大的企业为协同加工企业。最后实例分析,该算法可以更好地解决加工企业设备使用时间存在限制并带有交货期和收益的企业车间协同综合调度问题。     

IGBT芯片静态输出曲线连续测量方法

绝缘栅双极型晶体管(IGBT)芯片的静态输出曲线是考核其能量损耗及指导多芯片并联设计的重要指标之一。现有测量IGBT静态输出曲线的方法多采用商用化的功率器件分析仪,然而商业化功率器件分析仪存在价格昂贵、夹具单一的问题。亟需开发一种简单、快速、有效的静态输出曲线测量方法。面向高压IGBT芯片,提出一种新的静态输出曲线连续测量方法及测试电路,有效减小了IGBT芯片的电导调制效应和温升效应对静态输出曲线的影响。通过实时测量动态过程中的电压及电流,可以快速得到IGBT芯片静态输出曲线。通过对比本文连续法与功率器件分析仪的测量结果,证明了所提方法的有效性。     

基于AMC和HARQ的大气激光通信跨层系统性能研究

针对大气激光通信中由大气湍流引起的系统性能下降问题,研究了基于物理层自适应调制编码(AMC)和数据链路层混合自动请求重传(HARQ)的大气激光通信跨层系统性能。在建立了大气湍流信道瞬时信噪比模型的基础上,建立了大气激光通信AMC-HARQ系统模型,并推导了系统误包率和频带利用率公式,最后在双伽马信道模型下进行了仿真分析。仿真结果表明,大气激光通信AMC-HARQ系统能够在保证一定误包性能的条件下,大大提高系统频带利用率,提高单一应用AMC时的系统误包性能。随着重传次数增加,误包率和频带利用率均提高,但频带利用率增幅随重传次数增加而减小。     

多专业网连接性业务管理研究

根据多专业网连接性业务的管理需求,基于电信运营图(TOM,Telecom Operations Map),提出了连接性业务的管理框架,以实现多专业网连接性业务配置和维护的自动化;讨论了多专业网连接性业务管理框架中多专业网综合网管系统和专业网网管系统之间的管理接口;提出了配置和故障管理的管理接口功能需求和信息模型;以及基于 CORBA的实现。     

Littman光栅外腔可调谐Yb3+双包层光纤激光器

本文对LD泵浦的光栅外腔可调谐双包层Yb3 光纤激光器进行了实验研究．采用Littman外腔结构，研究了Yb3 光纤激光器的调谐特性．输出激光调谐范围42nm，谱线宽度0．08nm，最大输出功率达到了460mW，斜率效率约30％．并对其输出光功率随波长的变化进行了观测和分析．