舰船可视化指挥调度通信系统设想

本文结合当前舰船指挥调度通信系统的大趋势，设想了一个指挥调度系统可视化方案，组建了一个有线／无线混合的可视化指挥调度系统，说明了此系统的功能及关键技术，并在理论上阐述了方案的可行性。     

不同方向交替干扰方法对抗雷达旁瓣对消技术

由于现代雷达采用了旁瓣对消技术，使得传统方式的旁瓣干扰几乎完全失去效果。本文提出了一种针对旁瓣对消雷达的交替干扰方法，即在不同方向布置干扰机对同一部旁瓣对消雷达实施时间上的交替干扰。通过理论分析和模拟可知，其干扰功率甚至高于双方都不采用特殊技术时（即干扰方采用一般的旁瓣干扰，雷达方不采用旁瓣对消）的旁瓣干扰功率14dB以上。     

Highly Efficient Three Primary Color Organic Single‐Crystal Light‐Emitting Devices with Balanced Carrier Injection and Transport

Organic single crystals have a great potential in the field of organic optoelectronics because of their advantages of high carrier mobility and high thermal stability. However, the application of the organic single crystals in light‐emitting devices (OLEDs) has been limited by single‐layered structure with unbalanced carrier injection and transport. Here, fabrication of a multilayered‐structure crystal‐based OLED constitutes a major step toward balanced carrier injection and transport by introducing an anodic buffer layer and electron transport layer into the device structure. Three primary color single‐crystal‐based OLEDs based on the multilayered structure and molecular doping exhibit a maximum luminance and current efficiency of 820 cd cm^?2 and 0.9 cd A^?1, respectively, which are the highest performance to date for organic single‐crystal‐based OLEDs. This work paves the way toward high‐performance organic optoelectronic devices based on the organic single crystals.     

Analysis and implementation of variable step size adaptivealgorithms

Stochastic gradient adaptive filtering algorithms using variable step sizes are investigated. The variable-step-size algorithm improves the convergence rate while sacrificing little in steady-state error. Expressions describing the convergence of the mean and mean-squared values of the coefficients are developed and used to calculate the mean-square-error evolution. The initial convergence rate and the steady-state error are also investigated. The performance of the algorithm is studied when a power-of-two quantizer algorithm is used, and finite-word-length effects are considered. The analytical results are verified with simulations encompassing variable applications. Two CMOS implementations of the variable-step-size, power-of-two quantizer algorithm are presented to demonstrate that the performance gains are attainable with only a modest increase in circuit complexity     

Guanidine and Galactose Decorated Nanophotosensitizer with Oxygen Self-Sufficient Capability for the Localized Ablation of Oral Biofilm

Dental caries is a common disease caused by plaque biofilms, which are important pathogenic factors in many diseases. When hosts are overexposed to dietary sugars, pathogens such as Streptococcus mutans (S. mutans) and other cariogenic bacteria, metabolically assemble an extracellular matrix rich in exopolysaccharides to form a disease-causing biofilm, in which the microenvironment is characterized by regional hypoxia, low pH, and nutritional deprivation. Current antimicrobials with inadequate penetration and a lack of pathogens targeting the biofilm do not degrade the protective matrix within the biofilm. In this study, a guanidine and galactose decorated nanophotosensitizer with oxygen self-sufficient capability, p(GF/GEF)-I, is developed to enhance the permeability of biofilms by positively charging the particle surface and easily binding to the bacteria within the membrane through electrostatic interactions. 90% of the biofilm on enamel surface is eliminated after treatment with p(GF/GEF)-I under laser irradiation. Notably, the nanophotosensitizer inhibits the recolonization of dental biofilms by S. mutans, preventing secondary infections. Furthermore, dental caries in a rodent model are reduced with exposure to nanophotosensitizer. p(GF/GEF)-I is a significantly higher efficacy without damaging the surrounding soft tissue. With further development and optimization, p(GF/GEF)-I shows significant potential as a phototherapeutic agent for the treatment of biofilm-induced diseases.     

纳秒量级脉冲光纤激光器研究进展

脉冲光纤激光器作为当前国内外激光领域研究的热点之一,其应用越来越广泛。介绍了获取纳秒量级脉冲激光输出的两种典型结构,并基于相应原理分析了各自的关键性技术。概括了国内外该方向的研究进展,提出了有待于解决的若干问题,最后对脉冲光纤激光器的应用和发展前景进行展望。     

MIMO-OFDM系统中的一种空时频编码方案

基于MIMO-OFDM系统,本文提出了一种空时频编码方案,其利用扩展码,使数据符号在空域、时域、频域得到扩展,通过设置合适的参数,能够在频率选择性衰落信道下获得满空间分集和满频率分集,同时该方案的编解码复杂度不高。仿真结果表明,该方法在低信噪比下,也具有良好的误码率性能。     

基于LPC2368的操作系统设计

在嵌入式系统开发的过程中,有时由于系统规模小、资源少而无需嵌入操作系统,这给习惯在操作系统下编程的开发人员带来很大的不便,针对这种情况该文在LPC2368上设计了一个轻型操作系统,实现了轮询式的任务调度,解决了无操作系统环境下编程的困扰。     

基于PADS2004的高速PCB设计

在高速印刷电路板设计过程中,仅依靠个人经验布线,往往存在巨大的局限性,因而高速电路设计的仿真显示出越来越重要的地位。借助仿真软件,通过对高速信号线进行布局布线前仿真和布局布线后仿真,可以发现和解决信号完整性、串扰、EMC等问题。本文主要介绍了使用PADS2004/hyperLynx软件进行印刷电路板的仿真,通过对高速数字电路中的阻抗匹配、传输线长度及EMC问题的仿真,根据仿真结果分析给出了相应解决办法。文章还对高速电路设计中电源层分配、时钟设计进行了讨论。