Joint Optimization of Control Strategy and Energy Consumption for Energy Harvesting WSAN

With the rapid development of wireless sensor technology, recent progress in wireless sensor and actuator networks (WSANs) with energy harvesting provide the possibility for various real-time applications. Meanwhile, extensive research activities are carried out in the fields of efficient energy allocation and control strategy design. However, the joint design considering physical plant control, energy harvesting, and consumption is rarely concerned in existing works. In this paper, in order to enhance system control stability and promote quality of service for the WSAN energy efficiency, a novel three-step joint optimization algorithm is proposed through control strategy and energy management analysis. First, the optimal sampling interval can be obtained based on energy harvesting, consumption, and remaining conditions. Then, the control gain for each sampling interval is derived by using a backward iteration. Finally, the optimal control strategy is determined as a linear function of the current plant states and previous control strategies. The application of UAV formation flight system demonstrates that better system performance and control stability can be achieved by the proposed joint optimization design for all poor, sufficient, and general energy harvesting scenarios.     

(112)B碲锌镉衬底表面Everson腐蚀坑与材料缺陷的关系

通过研究碲锌镉衬底(112)B面缺陷腐蚀坑和(111)B面缺陷腐蚀坑之间的关系,揭示了(112)B面腐蚀坑与材料缺陷之间的关系.结果显示,Everson腐蚀剂在碲锌镉材料(112)B面上揭示的棒状腐蚀坑起源于材料中的体缺陷,或由延伸缺陷腐蚀坑在缺陷终止后演变而成,三种典型形状的锥形腐蚀坑分别来自延伸方向为<110>、<...     

微电子专业的通才和专才培养模式

国内微电子产业迅猛发展,支持在低端产品的基础技术人员的储备已经达到相当规模,但自主研发高端产品的专业人才匮乏。目前高等学校微电子专业改革中,在通才和专才培养模式之间很难找到平衡点。本文通过对比中美的微电子人才培养模式,讨论微电子专业通才和专才的培养模式。     

激光大气传输相位不连续点的探测实验

利用30×30 Hartmann-Shack波前传感器对激光在大气中传输时产生的相位不连续点进行了探测.实验结果与数值模拟结果对比分析表明:强湍流条件下,探测到了相位不连续点,实验结果与数值模拟结果基本相符,并充分说明了相位不连续点是成对出现的.利用激光大气传输四维程序对激光大气传输相位不连续性问题进行了数值计算,分析了发射口径和网格精度对相位不连续点数密度的影响.     

网络多层语义深度挖掘及流媒体缓存策略研究

对网络音视频数据进行多层次语义的深度挖掘,统计分析用户行为,建立一个流行度预测模型,在此基础上提出智能化的代理缓存替换策略.初步模拟实验表明该策略能提高缓存字节命中率,减短客户端的请求延迟时间.     

Level Statistics Crossover of Chiral Surface States in a Three-Dimensional Quantum Hall System

Recent experiments have demonstrated the realization of the three-dimensional quantum Hall effect in highly anisotropic crystalline materials, such as ZrTe|_5 and BaMnSb_2. Such a system supports chiral surface states in the presence of a strong magnetic field, which exhibit a one-dimensional metal-insulator crossover due to suppression of surface diffusion by disorder potential. We study the nontrivial surface states in a lattice model and find a wide crossover of the level-spacing distribution through a semi-Poisson distribution. We also discover a nonmonotonic evolution of the level statistics due to the disorder-induced mixture of surface and bulk states.     

Tunnel visible light communication system utilizing frequency domain pre-equalization technique

Simultaneously improving the communication speed and equalizing the nonlinear frequency response are still challenging for tunnel visible light communication(TVLC) system. Here, we propose and numerically investigate a frequency domain pre-equalization scheme for discrete multitone(DMT) modulation TVLC system. The amplitude of each subscriber is appropriately pre-equalized by optimized nonlinear compensation parameters. Simulation results demonstrate that our proposed equalization technique can ...     

炉管制程工艺中的片数效应及其优化方案

随着半导体技术的发展,越来越多的立式炉管在200mm及300mm集成电路晶圆制造中被应用到。同时炉管制程中的片数效应随着集成电路芯片的集成度越来越高而被凸显出来。文章将以LPCVD氮化硅在0.16μm、64M堆叠式内存制造过程中的片数效应为例,阐述炉管制程工艺中的片数效应以及通过调整制程参数（温度、沉积时间）的方式予以解决的实例。文中通过调整炉管上中下的温度来补偿气体的分布不均匀,调整沉积时间来补偿不同片数的沉积速率的差异,两者结合并辅以基于片数的分片程式来解氮化硅电介质沉积的片数效应。同时以此为基础总结出炉管片数效应的解决方案。     

JPEG2000中算术编码的VLSI结构设计

算术编码算法对于无损数据压缩是一种非常有效的方法,它已经被JPEG2000标准所采用.通过研究JPEG2000标准中的算术编码算法,设计了一种算术编码器的VLSI结构.该设计用Verilog语言进行了RTL级描述,然后用Modelsira对电路进行了仿真,经Quartus综合以后在FPGA上进行了验证.实验表明,在Ahera的芯片EP2C35F672C8上,该设计最高工作时钟可达63.37 MHz,可以作为IP核应用于JPEG2000图像编码芯片中.     

短沟Trench MOSFET阈值电压解析模型

传统MOS器件的阈值电压模型被广泛地用于分析Trench MOSFET的阈值电压,这种模型对于长沟道和均匀分布衬底的MOS器件来说很合适.但是对于Trench MOSFET器件来说却显现出越来越多的问题,这是因为Trench MOSFET的沟道方向是垂直的,其杂质分布也是非均匀的.本文基于二维电荷共享模型,给出了Trench MOSFET的一种新的阈值电压解析模型,该模型反映了器件的阈值电压随不同结构和工艺参数变化的规律,模型的结果和器件仿真软件Sivaco TCAD的仿真结果吻合较好.该模型较好地解决了以往所用的Trench MOSFET阈值电压模型计算不准确的问题.