电控双燃料压燃式发动机的研究

采用天然气作主要燃料柴油作辅助燃料的双燃料发动机,因天然气燃烧污染低将会得到广泛的应用,采用高性能,高集成度,模块化的M68300系列单片机开发电控单元ECU,提高发动机性能,并基于此电控单元开发出智能化,结构化的控制策略。     

Electrolyte materials for intermediate-temperature solid oxide fuel cells

Solid oxide fuel cells (SOFCs) directly convert chemical energy that is stored in a wide range of fuels into direct current electricity, with high efficiency and low emissions, via a series of electrochemical reactions at elevated operating temperatures (generally 400–1000 °C). During such an energy conversion process, the properties of electrolyte materials determine the working principle and operating temperature of the SOFC. When considering the cost and stability, lowering the operating temperature is critical, and this has become one of the developing trends in SOFC research. The key point for realizing a reduction in operating temperature is to maintain low ohmic resistance of the electrolyte and low polarization resistance of the electrodes. In practice, the mechanical and chemical stability of the electrolyte is also a big concern. According to their differences in ion conduction mechanisms, there are three main types of electrolyte material available, namely, oxygen ion-conducting, proton-conducting, and dual ion-conducting electrolytes. In this review, we give a comprehensive summary of the recent advances in the development of these three types of electrolyte material for intermediate-temperature SOFCs. Both conductivity and stability are emphasized. In conclusion, the current challenges and future development prospects are discussed.     

Dual Adaptive Turbo Coded Modulation for Integrated Multimedia Service Transmission

This paper proposes a cross-layer dual adaptive coded modulation architecture using turbo codes for mobile multimedia communication, which adapts to both the varying channel characteristics and the QoS of various multimedia services simultaneously to increase the average system throughput substantially. A pragmatic channel-adaptive turbo coded modulation scheme, which comeswithin 2.5 dB of the Shannon limit, is optimally designed,and then a QoS-adaptive scheme is superimposed to buildthe dual adaptive architecture. Simulation results show thatthe novel dual adaption reduces the gap from the fadingchannel capacity to 2 dB when assuming different servicesoccur in equal probability and the service duration followsexponential distribution.     

核空间的对偶上随机微分方程解的存在唯一性

本文在［１］的基础上，讨论了关于非时齐Ｗｉｅｎｅｒ积分的Ｉｔ类随机微分方程的解的存在唯一性．     

"两硬"条件下大倾角煤层开采技术的研究

以8102工作面开采为例，详细叙述“两硬”条件下大倾角煤层的开采技术实践，为同等条件下的煤层开采提供宝贵的实践经验。     

纯整数规划的一种解法

给出了纯整数规划问题的一种异于传统方法的解法。其特点是引进的线性约束条件是从目标函数中产生的。     

一类平面图的生成树数目

利用平面图的对偶图的Kirchhoff矩阵来求一些平面图的生成树数目,求这类平面图的生成树数目比直接利用Cayley公式要简单,且该方法对于同一类的平面图可以进一步推广.     

Banach空间中迫近子空间的判据

本文在Bnach空间中,对于一个具体子空间,给出它为迫近子空间的充分必要条件。     

双棱镜干涉实验中条纹的形状,间隔和可见度

在理论上对双棱镜干涉实验的条件,条纹的形状和间隔进行了详细地论述,计算出了条纹的可见度以及狭缝的最佳宽度。     

双透镜无狭缝一步彩虹全息

用双透镜记录三维漫射物体的一步彩虹全息图,此方法在曝光过程中只移动一个透镜就可以在观察的位置形成合成狭缝．两个透镜用一个短焦透镜以增加可视角和使狭缝变窄,同时也提高了分辨率和光能的利用率．