紫外光通信协作编队无人机联盟围捕算法

编队无人机对目标无人机进行围捕是多无人机战场作战中重要且典型的任务之一，本文将无线紫外光通信技术与围捕算法结合，提出了一种紫外光通信协作编队无人机联盟围捕算法。该算法借助无线紫外光辅助无人机编队机间数据保密传输和非直视通信，将联盟生成算法与区域最小化策略进行融合，采用动态规划法对最优联盟结构进行求解，使用区域最小化策略对目标无人机实施空中围捕，完成在复杂场景中无人机编队高效围捕多目标任务。对区域最小化策略和本文提出的紫外光协作编队无人机联盟围捕算法进行了仿真对比，实验结果表明：所提出的紫外光协作编队无人机联盟围捕算法在无人机编队围捕多目标过程中平均降低了12.73%的能耗，算法迭代次数平均降低了27.49%，验证了该算法能耗少、围捕效率高的性能。     

基于JAYA算法的紫外光通信无人机编队路由优化

紫外光通信由于其灵活性高、安全性好和全天候工作等优点,被认为是应急通信用无人机编队(UAV)的有潜力通信解决方案。为了提升紫外光通信无人机编队的有效作业时间,该文基于低功耗自适应集簇分层(LEACH)算法,并结合JAYA智能优化算法提出一种新颖的路由优化算法(RJLEACH)。该方法被用来改善紫外光通信无人机编队的有效操作时间。应用该算法对不同结构的紫外光通信无人机编队路由优化,并与其它算法得到的结果进行了比较分析。结果表明,RJLEACH算法在簇首选举阶段降低了无人机节点间的剩余能量方差,并且通过搜索最优路由降低了簇间通信的能量消耗。最终使网络出现第1个死亡节点和出现1/2死亡节点的时间相比经典LEACH算法分别延长了31.8%和13.8%,同时明显提高了能量利用率,能够为灾区救援和应急通信等任务争取宝贵的时间。     

多旋翼无人机编队动态航路规划研究

针对多旋翼无人机的编队动态航路规划问题,提出一种蚁群算法和快速扩展随机树RRT算法相结合的改进混合算法。首先利用蚁群算法离线搜索全局航路代价最小的初始航路,在局部航路规划中提出"协同避障—重构"策略,同时运用改进RRT算法实时修正几何航路,使机群满足时间协同约束绕过静态威胁源和突发障碍物,编队飞行至目的地。仿真结果表明,提出的改进混合算法和策略能有效规划无人机动态无碰航路,相较普通RRT算法,航路最优性及局部航路在线搜索速率得到明显提升。     

基于一致性理论的四旋翼无人机分布式编队控制方法

介绍了图论和群体系统一致性的相关理论,提出一种分布式四旋翼无人机编队控制方法,将四旋翼无人机描述为二阶积分器动力系统,采用相对位置偏差描述编队队形;根据四旋翼无人机之间通信拓扑关系将四旋翼无人机编队建模为图,探索了领航跟随法和基于图论法的融合策略,给出一种有领航者的二阶一致性算法。在该算法下,编队可以完成编队集结和编队机动等行为,最后通过仿真实验验证了该方法的有效性。     

无人机集群编队控制方法研究综述

随着无人机技术的进一步发展，多无人机编队飞行的研究也受到了越来越多的关注。无人机相互配合组成编队群，可以充分发挥单个无人机所不具备的优势，更能胜任复杂、多任务场景下的工作。对无人机集群编队控制方法进行分类，分为传统控制法、群体智能算法、深度强化学习算法；对各类方法进行分析，着重归纳讨论了领导者-跟随者方法、人工势场法、运动学控制方法、蚁群优化算法、粒子群优化算法、人工蜂群算法、深度Q网络算法、深度确定性策略梯度算法、多智能体深度确定性策略梯度算法，并给出各自的优劣势；对无人机集群编队控制方法进行总结，指出传统控制法已接近成熟，但为了实现无人机的智能自主协同编队控制，仍需在群体智能算法和深度强化学习算法上融合新的思想与改进，从而发挥大数量无人机在复杂场景下的优势。     

多无人机编队自主重构的内点算法

考虑多无人机编队自主重构的优化设计问题,联合编队过程中的3类代价函数、无人机的非线性动力学方程以及4类不等式约束条件,构成一个非线性多目标优化模型。采用加权和策略并将所有的等式和不等式约束分别组合,将非线性多目标优化模型转化为一个标准的非线性单目标优化模型。采用运筹学中的内点算法来求解最优解,并在算法的实现过程中做了某些改进,以避免出现矩阵的秩亏损。从理论上证明多目标优化在加权和策略下与单目标优化间的等价性。最后用仿真算例验证了算法的有效性。     

考虑信息延迟的无人机分布式协同搜索算法

多无人机协同搜索是多无人机协同控制的重要内容之一,无人机协同搜索的两大问题是通讯延迟和分布式的计算环境。各无人机既要提高搜索效率又要避免碰撞。提出了一种以分布式模型预测算法为基础的搜索算法。通过引入合适的缓冲周期,安排不同的无人机分别对未来不同的时间范围进行规划。不同无人机的搜索规划在时间上不再耦合,从而解决了多机分布式计算和通讯延迟的问题。该方法的目的是实现真实环境下的分布式协同控制。最后用仿真算例验证了算法的可行性。     

无人机激光光电目标跟踪指示技术研究

无人机技术近年来发展迅速，军事应用日益广泛。传统机载激光目标指示器重量与体积较大，很难集成于无人机来实现军事应用。主要介绍了一种国际主流的激光制导武器系统技术方案及作战应用流程，并研究了一种轻小型化的三光合一的无人机激光光电目标跟踪指示载荷。有别于传统激光指示照射，该无人机激光光电载荷通过与无人机的紧耦合完成小型化集成，并实现了远近距离一体化探测功能：远距离可对打击目标进行定位引导(大地坐标位置信息)，近距离可对打击目标进行激光照射指示引导。同时，本文的指示方法利用低成本小型无人机突击作战，避免了人员暴露及伤亡风险，提高了无人化作战效率。     

基于改进人工蜂群算法的无人机的航迹规划

针对无人机飞行任务规划系统中的航迹规划问题,提出了一种改进的人工蜂群算法,将其应用于无人机的航迹规划。该算法将航迹规划问题转换成函数优化问题,以蜂群为搜索单位,通过群体之间的信息交流与优胜劣汰机制,使蜂群向更优方向进化。在雇佣蜂搜索阶段采用自适应搜索策略来加快算法收敛速度;在跟随蜂搜索阶段引入一种新的概率选择方式来保证种群的多样性;在侦察蜂搜索阶段利用混沌搜索算子提高算法的全局搜索能力。通过标准函数测试与航迹规划仿真对改进后的算法进行验证,结果表明,改进后的算法提高了全局收敛能力,在收敛速度和精度上优于传统的人工蜂群算法,可有效解决无人机的航迹规划问题。     

基于多目标遗传算法的异构无人机协同察打

针对多架异构无人机在未知环境下协同执行搜索打击任务。考虑无人机和目标资源问题,采用了一种组建联盟方式来完成打击任务,建立了组建联盟的多目标优化模型,并提出了一种并行带精英策略非支配排序的遗传算法(NSGA-Ⅱ)求解模型。通过具体的仿真验证了模型的合理性,分析了不同情况下的算法运行速度,并与传统方法进行对比,证明了并行NSGA-Ⅱ具有很强的实时性,且提高了任务的完成效率。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

中国建立EB级存储实验室,致力云计算应用(英文)

正With the support of 863 programs,Sugon Information Industry Co.,Ltd.,set up a dawning EB-class storage laboratory to address massive data storage requirements and largescale cloud computing demonstration applications.The Dawning EB-class cloud storage system adopts advanced fault-tolerant architecture,efficient data fault-tolerant algorithms with user authentication and data encryption policies to deal with the"lost""wrong"and"stolen"problems of data for ensuring the reliability and safety of the EB-class storage system in the public network application environments.The Dawning EB-class Storage Laboratory taking advan-