Modeling and simulation of InAs/GaAs quantum dot lasers

Based on the analysis of carrier dynamics in quantum dots (QDs), the numerical model of InAs/GaAs QD laser is developed by means of complete rate equations. The model includes four energy levels and among them three energy levels join in lasing. A simulation is conducted by MATLAB according to the rate equation model we obtain. The simulation results of PI characteristic, gain characteristic and intensity modulation response are reasonable. Also, the relations between the left facet reflectivity of laser cavity and threshold current as well as modulation bandwidth are studied. It is indicated that the left facet reflectivity increasing can result in reduced threshold current and improved modulation bandwidth, which is in accordance with experimental results. The internal mechanism of QD lasers is fully described with the rate equation model, which is helpful for QD lasers research.     

Application Aware Topology Generation for Surface Wave Networks-on-Chip

The networks-on-chip （NoC） communication has an increasingly larger impact on the system power consumption and performance. Emerging technologies, like surface wave, are believed to have lower transmission latency and power consumption over the conventional wireless NoC. Therefore, this paper studies how to optimize the network performance and power consumption by giving the packet-switching fabric and traffic pattern of each application. Compared with the conventional method of wire-linked, which adds wireless transceivers by using the genetic algorithm （GA）, the proposed maximal declining sorting algorithm （MDSA） can effectively reduce time consumption by as much as 20.4% to 35.6%. We also evaluate the power consumption and configuration time to prove the effective of the proposed algorithm.     

GSM网络掉话率的优化

本文对厦门GSM网络的掉话原因进行分析,并总结出各种具体的优化方法及其效果.     

西门子全集成自动化理念初探

系统阐述了全集成自动化理念的内涵，指出其特点在于统一的数据管理、统一的编程组态、统一的通讯以及无与伦比的开放性，其中采用WINCC与STEP7两个软件进行了说明，井提出全集成自动化应用将是今后自动化技术发展应用的方向。     

应用于光触发晶闸管触发的特种光纤性能分析

对光触发晶闸管应用中使用较广泛的一种特种光纤进行了性能分析,对该光纤的芯层与包层的掺杂和包层/芯层直径比等关键光学特性进行了系统的研究,为光触发晶闸管寻找到性价比较优的特种光纤提供了参考。通过对比分析得出,在光触发晶闸管触发应用中,光纤设计类型为芯层直径200μm,包层直径250μm;采用阶跃折射率分布设计;芯层掺杂为锗氟共掺,芯层掺杂量为锗元素16mol%、氟元素5mol%;包层掺杂为氟元素,包层掺杂量为1mol%的光纤触发性能较优,适合光触发晶闸管的应用。     

无线网络优化经验浅谈之处理呼叫建立成功率低的方法

本文描述了无线网络优化中呼叫建立成功率低的处理思路和方法。     

国外战术导弹半实物仿真试验验证能力发展分析

半实物仿真是战术导弹等先进武器装备在研制试样、性能评估、作战演练中必不可少的主要仿真方法和手段。从多物理场/控制耦合、导航、多模/宽谱段制导、导引头抗干扰、靶场试验等五个方面,介绍了国外战术导弹半实物仿真试验设备、试验技术的具体情况,分析了其半实物仿真验证能力的发展现状及发展趋势,提出了战术导弹半实物仿真应重点关注在复杂战场环境、新型物理效应、多弹协同/多体飞行器协同等方面的能力建设,分析结果可对未来战术导弹半实物仿真能力建设发展具有借鉴意义。     

Matrix Manipulation of Directly-Synthesized PbS Quantum Dot Inks Enabled by Coordination Engineering

The direct-synthesis of conductive PbS quantum dot (QD) ink is facile, scalable, and low-cost, boosting the future commercialization of optoelectronics based on colloidal QDs. However, manipulating the QD matrix structures still is a challenge, which limits the corresponding QD solar cell performance. Here, for the first time a coordination-engineering strategy to finely adjust the matrix thickness around the QDs is presented, in which halogen salts are introduced into the reaction to convert the excessive insulating lead iodide into soluble iodoplumbate species. As a result, the obtained QD film exhibits shrunk insulating shells, leading to higher charge carrier transport and superior surface passivation compared to the control devices. A significantly improved power-conversion efficiency from 10.52% to 12.12% can be achieved after the matrix engineering. Therefore, the work shows high significance in promoting the practical application of directly synthesized PbS QD inks in large-area low-cost optoelectronic devices.