机载大规模复杂软件开发及验证技术

针对航空电子系统结构综合化、硬件共享化、功能软件化引发软件规模、复杂度指数级上升的趋势,分析了软件开发、软件综合以及软件测试的困难和挑战,并从开发技术、测试验证技术和项目管理3个维度,结合模型驱动开发、软件复用、虚拟仿真验证、DO-297规范、CMMI等技术和管理方法,为机载大规模复杂软件开发及验证提供了解决方案,提高软件的可靠性,缩短软件的研发周期。     

面向航空电子系统的网络文件系统设计

针对IMA的多个应用模块的文件共享问题,基于具有自主知识产权的机载多分区实时OS平台,提出了一种网络文件系统NFS的设计方案。文中采用网络文件锁,通过对文件的上锁和解锁,实现多个分区互斥访问文件;使用权限验证机制验证用户对文件的访问权限,用户通过验证后方可对文件执行相应的操作;日志文件保存整个NFS的运行情况,用于对NFS性能的分析。文中阐述了NFS客户端、服务器端的设计和网络封装格式,并给出了NFS运行的原理图。     

基于SOA中四波混频效应的全光波长变换

基于半导体光放大器的四波混频效应进行了 2 .5 Gbit/s的光脉冲的波长变换。向上波长变换间距为 1 0 nm,向下变换间距大于 1 0 nm。对基于半导体光放大器四波混频效应的波长变换技术进行了较为详尽的试验报道     

铝-RIE刻蚀工艺

干法刻铝中 ,BCl3添加 Cl2 、CHCl3和 N2 ,可改变 Al的刻蚀速率、Al对 Si O2 和胶的选择性、线宽和胶膜质量 ,其中 Cl2 流量影响最大。此外 ,本文还给出 RF功率和气压的影响。采用适当的气体组合、不太高的功率和不太低的气压 (BCl3∶ Cl2 ∶ CHCl3∶ N2 =70 sccm∶ 1 5 sccm∶ 1 0 sccm∶ 0～ 5 0 sccm,2 0 0 m Torr,2 0 0 W)可以实现细线条 (0 .6μm) Al的刻蚀。     

LD泵浦的声光调Q腔内倍频固体激光器

应用国产的８０８ｎｍ激光二极管（ＬＤ）研制了声光调Ｑ的Ｎｄ：ＹＶＯ４－ＫＴＰ腔内倍频的准连续、单脉冲激光器,得到了ＴＥＭ００模、频率为２０ｋＨｚ的准连续稳定的５３２ｎｍ原绿光输出,阈值泵浦功率为３００ｍＷ。在连续２Ｗ的泵浦功率下,准连续绿光输出为１２０ｍＷ,脉冲宽度为４０ｎｓ,单脉冲能量为５０μＪ,通过对声光Ｑ开关的驱动电源改造,得到了单脉冲激光输出。在分析计算的基础上,建立了２Ｗ、８０８ｎｍＬＤ     

利用SOA交叉增益调制实现2.5 Gbit/s非归零码的全光波长变换

采用半导体光放大器 (SOA)的交叉增益调制进行了 2 5Gbit/s的非归零码光脉冲的波长变换。向下波长变换间距大于 2 0nm ,向上波长变换间距大于 10nm。对变换信号测量了接收机入纤功率和误码率的关系。实验中采用同向变换的方式 ,信号光中心波长固定 ,探测光采用外腔半导体激光器 ,中心波长连续可调。对变换信号进行了至少 1h的测量 ,误码为零。为其在波分复用(WDM)网络中的应用奠定了基础。     

A direct digital frequency synthesizer with high-speed current-steering DAC

A high-speed SiGe BiCMOS direct digital frequency synthesizer (DDS) is presented. The design in tegrates a high-speed digital DDS core, a high-speed differential current-steering mode 10-bit D/A converter, a serial/parallel interface, and clock control logic. The DDS design is processed in 0.35 μm SiGe BiCMOS standard process technology and worked at 1 GHz system frequency. The measured results show that the DDS is capable of generating a frequency-agile analog output sine wave up to 400+ MHz.     

Efficiency Roll‐Off in Blue Emitting Phosphorescent Organic Light Emitting Diodes with Carbazole Host Materials

The efficiency roll‐off in blue phosphorescent organic light emitting diodes (OLEDs) using different carbazole compounds as the host is systematically studied. While there is no significant difference in device efficiency, OLEDs using ter‐carbazole as the host show a reduction in efficiency roll‐off at high luminance. Data from transient photoluminescence and electroluminescence measurements show that the lower triplet–triplet annihilation (TTA) and triplet–polaron quenching (TPQ) rates in devices with the ter‐carbazole host compared with other carbazole hosts are the reasons for this reduced efficiency roll‐off. It is also found that the host materials with low glass transition temperatures are more susceptible to the efficiency roll‐off problem.     

Well‐Defined Protein‐Based Supramolecular Nanoparticles with Excellent MRI Abilities for Multifunctional Delivery Systems

Protein‐based nanoparticles are widely used for effective biomedical applications. The objective of this work is to design series of magnetic resonance imaging (MRI)‐visible cationic supramolecular nanoparticles (PGEA@BSA‐Ad/Gd³⁺) based on bovine serum albumin (BSA) and β‐cyclodextrin‐cored star ethanolamine‐functionalized poly(glycidyl methacrylate) (CD‐PGEA) in the presence of Gd³⁺ ions for multifunctional delivery systems. CD‐PGEA is prepared via atom transfer radical polymerization and ring‐opening reaction. It is found that in the absence of Gd³⁺ ions, CD‐PGEA does not well interact with adamantine‐modified BSA (BSA‐Ad). The well‐defined PGEA@BSA‐Ad/Gd³⁺ supramolecular nanoparticles could be produced through the synergistic actions of the host–guest and electrostatic self‐assemblies by mixing aqueous solutions of CD‐PGEA, BSA‐Ad, and Gd³⁺. In comparison with CD‐PGEA assembly units, such kinds of uniform PGEA@BSA‐Ad/Gd³⁺ supramolecular nanoparticles exhibit better pDNA condensation ability, lower cytotoxicity, higher gene transfection, and easier cellular uptake. In addition, PGEA@BSA‐Ad/Gd³⁺ also produces outstanding MRI abilities, much better than Magnevist (Gd‐diethylenetriaminepentacetate acid). The present design of protein–polymer supramolecular nanoparticles with MRI contrast agents would provide a new way for multifunctional gene/drug delivery systems.     

Efficient and Stable Bifunctional Electrocatalysts Ni/NixMy (M = P,S) for Overall Water Splitting

Development of easy‐to‐make, highly active, and stable bifunctional electrocatalysts for water splitting is important for future renewable energy systems. Three‐dimension (3D) porous Ni/Ni₈P₃ and Ni/Ni₉S₈ electrodes are prepared by sequential treatment of commercial Ni‐foam with acid activation, followed by phosphorization or sulfurization. The resultant materials can act as self‐supported bifunctional electrocatalytic electrodes for direct water splitting with excellent activity toward oxygen evolution reaction and hydrogen evolution reaction in alkaline media. Stable performance can be maintained for at least 24 h, illustrating their versatile and practical nature for clean energy generation. Furthermore, an advanced water electrolyzer through exploiting Ni/Ni₈P₃ as both anode and cathode is fabricated, which requires a cell voltage of 1.61 V to deliver a 10 mA cm^?2 water splitting current density in 1.0 m KOH solution. This performance is significantly better than that of the noble metal benchmark—integrated Ni/IrO₂ and Ni/Pt–C electrodes. Therefore, these bifunctional electrodes have significant potential for realistic large‐scale production of hydrogen as a replacement clean fuel to polluting and limited fossil‐fuels.