东南沿海波导结构的预报方法

通过分析东南沿海地区可出现低空波导的天气形势，部位和有关天气要素及天气形势，天气要素的发展变化对波导结构发生发展和消亡过程的影响，得出了东南沿海波导结构出现的预报方法，、步骤及可以使用的一些参数。     

Ka频段脊波导过渡的仿真与工程应用

在分析各种过渡结构的基础上，用高频分析软件HFSS仿真设计了Ka频段直线型脊波导过渡和曲线型脊波导过渡结构，在31-38GHZ的宽带范围内，插入损耗小于0.35dB，实测结果与仿真结果基本符合，直线型脊波导结构简单，适合工程应用。     

锥面AWG能量密度及其色散特性的研究

基于阵列波导光栅(AWG)的结构特点，采用Bloch函数近似算法，建立了锥面波导的结构模型，考虑信号在波导中的辐射特性，讨论锥面AWG能量密度及其散射特性。结合作者前期在锥面AWG波导结构参数的研究工作，对锥面AWG进行了仿真计算。数值结果表明：锥面AWG布里渊区的中心区域辐射能量最大，并得到传输系数与轴向距离2及衍射角的关系，计算得到的基本参数与仿真结果相吻合。     

波导光栅耦合器

介绍了近几年国外波导光栅耦合器的研究和应用情况，重点介绍了光栅参数和波导结构对波导光栅耦耦器输入耦合效率的影响以及光栅耦合器在光盘读出头、传感器、光 谱分析等方面的应用。     

扁波导馈电的平板缝隙天线阵的带宽扩展

扁波导馈电的平板缝隙天线阵,除了馈电波导内部耦合增强以外,带宽也受到限制.文章从谱域角度分析了缝隙天线的内外场分布,在此基础上,得到了周期波导和金属波导中各模式场的功率/储能谱.计算了波导缝隙天线的Q值并分析其变化规律,解释了扁波导馈电带宽受限的原因是辐射波导内的驻波储能场增强造成的.提出了在缝隙两侧增加扼流槽的改进方案,并同样从谱域的角度分析了该方案对带宽改善的影响.将该方案应用于一个实际的SIW平板波导缝隙天线阵设计中,获得了8.1%的带宽.     

东南沿海对流层大气波导结构的出现规律

沿海地区和海上是有利于大气波导结构出现的地区，通常需要在这些地区开展专题试验研究来掌握当地的大气波导层结的出现情况，以便给无线电应用系统提供基础。文章介绍了1997年10月份在我国东南沿海地区开展的大气波导层结探测试验，详细讨论该试验得到的海上蒸发波导，近地大气波导和低空大气波导结的出现情况及它们和气象条件的关系。     

高功率平板波导激光器进展

详细介绍了平板波导二极管(LD)抽运高功率同体激光器的进展，分析了系统的优点和潜在的风险。具体讨论了接近式LD耦合方式、双包层波导结构和非稳腔的使用，以及梯形结构波导、集成被动调Q设计。激光介质包括Yb^3 ，Nd^3 和Tm^3 掺杂的YAG晶体材料。具有单片紧凑波导结构的激光器可以获得超过10W的激光输出，获得近衍射极限的激光束。将来可以实现100W以上的激光输出并在单片器件内集成更多的功能。     

理想匹配层及模式匹配法分析多段平面光波导结构

将理想匹配层（PML）吸收边界条件和模式匹配法用于多段平面光波导结构分析，给出了一种改进的平面光波导结构的PML吸收边界条件，并对光波导的光场分布进行数值模拟，所得结果表明了PML吸收边界条件应用于多段平面光波导结构分析的有效性。该方法也可用于分析复杂结构的平面光波导。     

阵列波导光栅复用器优化设计的数值计算

阵列波导光栅(AWG)复用／解复用器的优化设计计算是集成光波导器件设计计算中的难点．文章应用AWG光信号传输特性和光栅方程，提出了AWG组成部分输入／输出波导、阵列波导、平板波导相关参数及阵列波导结构优化设计的数值计算方法，给出了具体的计算数值；该计算方法解决了AWG复用器优化设计计算的问题，为进一步建立AWG的计算机辅助设计提供了基础．     

圆型槽波导的结构与损耗的关系

本文在圆型槽波导一级近似特征方程求解的基础上,分析了圆型槽波导的损耗并给出了它们与圆型槽波导结构尺寸之间的关系。     

Study of sectorial groove—gap RF structure for cusptron

A novel sectorial groove-gap RF structure for cusptron (gyromagnetron) is presented and its characteristic equation and stored energy expression are derived. The magnetron-like vane structure is a special case of this structure. The calculated curves of dispersion, energy and efficiency are given and the results show that maximum efficiency η=16.1% is obtained when the sectorial groove-gap is evolved to vane structure.     

Radiation Absorption Mechanism in Nonvolatile MNOS Structure

The γ-ray radiation will speed up the discharge of the stored charge in nonvolatile MNOS structure.The radiation absorption mechanism to enhance the discharge is discussed.A direct radiation emission model from the interface traps distributing both in energy level and in space is given.The theoretical results based on this model are in good agreement with experimental measurement.     

Calculation of the surface-wave excitation in multilayeredstructures

A novel rigorous analysis of the surface waves excited by a Hertzian dipole embedded in a multilayered structure is presented. A transmission-line resonator equivalent circuit is used to calculate the surface wave's electromagnetic field components. It is shown that the power carried by the surface waves is related to the energy stored in the resonator. An analytical method for the calculation of the stored energy is given. A simple algorithm iterating over the layers of the structure is derived to analytically calculate the surface wave's electromagnetic field components and the power carried by surface waves. The need of numerical integration or calculation of residues is omitted. This benefits a reduction in computation time and an improvement in accuracy and versatility of computer-aided design (CAD) programs. The presented method has been implemented in a microwave CAD program. Numerical results for planar antennas are presented     

星载腔体滤波器功率容量分析

介绍了星载腔体滤波器功率容量的仿真分析方法。先利用ADS电路模型计算出滤波器各腔的储能情况,再用HFSS仿真实际三维结构中谐振腔的储能,计算最易产生微放电部位处的电压值,最后给出了腔体滤波器能承受的最大功率理论计算公式。     

An Ant-Based On-Demand Energy Route Protocol for IEEE 802.15.4 Mesh Network

In this paper, an improved ant-based on-demand energy route (AOER) protocol for IEEE 802.15.4 mesh networks is presented. The information of network status is obtained by Forward_Ant and stored in an inversed pheromone table which simplifies the data structures of route packets. The simplified structure can avoid wasting of storage memories and processing capabilities which are very important for low-power wireless personal area network devices. The average path energy, average network energy and minimum remaining node energy of the path are combined to evaluate paths and update the inversed pheromone table. The positive and negative reinforcement of ant colony optimization algorithm are used to enhance the routes with better fitness. The pseudo-random-proportional-selection strategy is used to determine routes with the transferring of Backward_Ant from the destination to the source. Nodes with higher pheromone trail values are selected as the next hop with higher probabilities, therefore the network loads are distributed and nodes energy consumptions are balanced. A proactive route maintenance mechanism is also used in AOER to trigger route maintenance and avoid over-use of node energy. Experimental results on NS-2 show that AOER performs better than AODVjr in different network traffics and dynamics.     

Voltage equaliser for Li–Fe battery

In this article, a voltage equaliser is proposed for a battery string with four Li–Fe batteries. The proposed voltage equaliser is developed from a flyback converter, which comprises a transformer, a power electronic switch and a resonant clamped circuit. The transformer contains a primary winding and four secondary windings with the same number of turns connected to each battery. The resonant clamped circuit is for recycling the energy of leakage inductance of the transformer and for performing zero-voltage switching (ZVS) of the power electronic switch. When the power electronic switch is switched on, the energy is stored in the transformer; and when the power electronic switch is switched off, the energy stored in the transformer will automatically charge the battery whose voltage is the lowest. In this way, the voltage of individual batteries in the battery string is balanced. The salient features of the proposed voltage equaliser are that only one switch is used, the energy stored in the leakage inductance of the transformer can be recycled and ZVS is obtained. A prototype is developed and tested to verify the performance of the proposed voltage equaliser. The experimental results show that the proposed voltage equaliser achieves the expected performance.     

The Mantis Shrimp Saddle: A Biological Spring Combining Stiffness and Flexibility

Stomatopods are aggressive crustacean predators that use a pair of ultrafast raptorial appendages to strike on prey. This swift movement is driven by a power amplification system comprising components that must be able to repetitively store and release a high amount of elastic energy. An essential component of this system is the saddle structure, in which the elastic energy is stored by bending prior to striking. Here, a comprehensive study that sheds light on the microstructural and chemical designs of the stomatopod's saddle is conducted. MicroCT scans combined with electron microscopy imaging, elemental mapping, high‐resolution confocal Raman microscopy, and nanomechanical mapping show that the saddle is a bilayer structure with sharp changes in chemical composition and mechanical properties between the layers. The outer layer is heavily mineralized whereas the inner layer contains a high content of chitin and proteins, leading to a spatial organization of phases which is optimized for load distribution during saddle bending. The mineralized outer layer sustains compressive stresses, whereas the inner biopolymeric layer provides tensile resistance. These findings reveal that the saddle chemical composition and microstructure have been spatially tuned to generate a stiff, yet flexible structure that is optimized for storage of elastic energy.     

Tailoring of a Piezo-Photo-Thermal Solar Evaporator for Simultaneous Steam and Power Generation

Water and electricity shortages constitute a global energy crisis that cannot be ignored. The sun is an unlimited source of energy, and oceans provide abundant water and renewable energy resources. In this study, poly(vinylidene fluoride) (PVDF)/graphene solar evaporator membranes are fabricated for simultaneous freshwater production and power generation. Graphene addition transformed the PVDF crystal from the α-phase to the piezoelectric self-assembly β-phase. The resulting membrane is used to convert the mechanical energy of waves to electrical energy. The membrane has an output voltage of 2.6 V (±1.3 V) and an energy density of 2.11 Wm⁻² for 1 Hz simulated waves, which are higher than values reported in the literature. The stacked graphene and polymer formed a wood-lumens-like mesoporous structure with a photothermal effect. Under one sun illumination, the water production rate is 1.2 kg m⁻² h⁻¹, and the solar-thermal energy conversion efficiency is 84%. Finally, a prototype is built to prove a single evaporator's feasibility that can simultaneously obtain freshwater and generate electricity. Thus, this membrane serves as an ocean wave power generation device that can provide all-weather energy generation, convert stored electrical energy into thermal energy at night and on cloudy days, and continuously provide safe drinking water.     

Eddy power flow of electromagnetic waves

The energy transport velocity of electromagnetic waves is reformulated to interpret the energy transport of non-piano waves by extending the classical concept of the stored energy flow of plane waves. The dyadic phase velocity, dyadic energy velocity, and stored energy vector are proposed. A new concept of eddy power flow is given, with which a well-known contradiction of energy transport velocity in waveguides can be solved.     

Techniques for Leakage Energy Reduction in Deep Submicrometer Cache Memories

The techniques known in literature for the design of SRAM structures with low standby leakage typically exploit an additional operation mode, named the sleep mode or the standby mode. In this paper, existing low leakage SRAM structures are analyzed by several SPEC2000 benchmarks. As expected, the examined SRAM architectures have static power consumption lower than the conventional 6-T SRAM cell. However, the additional activities performed to enter and to exit the sleep mode also lead to higher dynamic energy. Our study demonstrates that, due to this, the overall energy consumption achieved by the known low-leakage techniques is greater than the conventional approach. In the second part of this paper, a novel low-leakage SRAM cell is presented. The proposed structure establishes when to enter and to exit the sleep mode, on the basis of the data stored in it, without introducing time and energy penalties with respect to the conventional 6-T cell. The new SRAM structure was realized using the UMC 0.18-mum, 1.8-V, and the ST 90-nm 1-V CMOS technologies. Tests performed with a set of SPEC2000 benchmarks have shown that the proposed approach is actually energy efficient