Research on Hybrid Scheduling Algorithm Based on CAN bus

In view of the problem that the packet information preempted network resources in the process of transmission in the CAN bus, which leads to the low utilization of network resources and the low accuracy of information transmission. Thus, a hybrid scheduling algorithm NMTS based on CAN bus is proposed, in the NMTS hybrid scheduling algorithm, the dynamic scheduling algorithm EDF is used to schedule hard real-time messages to solve the problem of low utilization of network resources; the static scheduling algorithm RMS is used to schedule soft real-time messages and non real-time messages, so as to solve the problem of low accuracy of information transmission. By using MATLAB software, the CAN network model can be built, the EDF algorithm, RMS algorithm and NMTS algorithm are simulated. The experimental results show that the network resources utilization is 90%, the packet loss rate is 0% of the NMTS algorithm. Therefore, The hybrid scheduling algorithm based on CAN bus NMTS has the characteristics of high network resource utilization and high accuracy of information transmission, which will be very helpful for further research of CAN bus.     

慢光产生的新机理及其应用

通过对比和研究电磁感应透明、相干布居振荡、受激布里渊散射和光子晶体波导等几种使光速变慢的主要技术，论述了近10年中的慢光技术重要理论和技术上的发展以及这些发展对慢光性能的改善及存在的问题与不足，重点介绍了近几年慢光产生的一些新技术及初步应用，并预测了慢光技术今后的发展趋势及潜在应用。本文的研究表明，慢光在光纤传感以及其它领域中将会有越来越重要的应用价值。     

Interface science for optimizing the size of oxidic nanoparticles in supported catalysts

In the present work we attempt to optimize the size of the supported “molybdenum oxide”/titania and “cobalt oxide”/γ-alumina nanoparticles formed after calcination by “selecting”, respectively, the proper mode of deposition and the local structure of the deposited species achieved upon the impregnation step of catalyst preparation. Concerning the first system, it was found that the disubstituted Mo inner sphere surface complexes, which are bound on the support surface stronger than the monosubstituded ones, resist more effectively to the sintering taking place during calcination where the above complexes are transformed progressively into MoO₃ supported nanoparticles. This leads to a catalyst with very small MoO₃ nanoparticles and thus with very high activity for the selective reduction of NO by NH₃. Concerning the “cobalt oxide”/γ-alumina catalysts, it was found that a relatively large (small) size of the supported nanocrystallites is imposed by the bulk deposition (formation of inner sphere surface complexes). A quite small size of the supported “cobalt oxide” nanocrystallites, not strongly interacted with the support surface, is imposed by the interface precipitation. This is the optimum supported phase for the complete oxidation of benzene.     

Molybdenum-titanium oxide catalysts: the influence of the preparation conditions on their activity for the selective catalytic reduction of NO by NH3

MoO₃/TiO₂ catalysts of varying molybdenum content were prepared at various pHs and concentrations of the impregnating solution using the equilibrium deposition filtration (EDF) method. Moreover, a catalyst corresponding to the EDF one with the maximum Mo loading was prepared using the conventional non-dry impregnation (NDI) method. The above catalysts were characterized using X-ray powder analysis, diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy, and tested for the selective catalytic reduction of NO by NH₃ in the temperature range 250–450 °C. It was found that the application of EDF results in an improved MoO₃/TiO₂ catalyst exhibiting higher activity than the corresponding sample prepared by the conventional NDI method. The catalytic activity correlates well with the concentration of the Mo species strongly interacting with the anatase surface. The concentration of the above species is maximized when the EDF method is employed to prepare the catalysts. This is especially, so when low pH and Mo concentration of impregnating solution are used.     

1.48μm泵浦的EDFA理论模型的修正与数值解

本文所建立的ＥＤＦＡ的理论模型考虑了ＡＳＥ和光纤的本征衰耗，修改了速率方程和传输方程，对泵浦光功率，信号光功率沿光纤长度的分布及ＥＤＦＡ增益特性等进行了数值解，所得结果与实验结果符合较好。     

A non-preemptive scheduling algorithm for soft real-time systems

Real-time systems are often designed using preemptive scheduling and worst-case execution time estimates to guarantee the execution of high priority tasks. There is, however, an interest in exploring non-preemptive scheduling models for real-time systems, particularly for soft real-time multimedia applications. In this paper, we propose a new algorithm that uses multiple scheduling strategies for efficient non-preemptive scheduling of tasks. Our goal is to improve the success ratio of the well-known Earliest Deadline First (EDF) approach when the load on the system is very high and to improve the overall performance in both underloaded and overloaded conditions. Our approach, known as group-EDF (gEDF) is based on dynamic grouping of tasks with deadlines that are very close to each other, and using Shortest Job First (SJF) technique to schedule tasks within the group. We will present results comparing gEDF with other real-time algorithms including, EDF, Best-effort, and Guarantee, by using randomly generated tasks with varying execution times, release times, deadlines and tolerance to missing deadlines, under varying workloads. We believe that grouping tasks dynamically with similar deadlines and utilizing a secondary criteria, such as minimizing the total execution time (or other metrics such as power or resource availability) for scheduling tasks within a group, can lead to new and more efficient real-time scheduling algorithms.     

Variations of a passive safety containment for a BWR with active and passive safety systems

The paper presents variations of a certain passive safety containment for a near future BWR. It is tentatively named Mark S containment in the paper. It uses the operating dome as the upper secondary containment vessel (USCV) to where the pressure of the primary containment vessel (PCV) can be released through the upper vent pipes. One of the merits of the Mark S containment is very low peak pressure at severe accidents without venting the containment atmosphere to the environment. Another merit is the capability to submerge the PCV and the reactor pressure vessel (RPV) above the core level by flooding water from the gravity-driven cooling system (GDCS) pool and the upper pool. The third merit is robustness against external events such as a large commercial airplane crash owing to the reinforced concrete USCV. The Mark S containment is applicable to a large reactor that generates 1830 MW electric power. The paper presents several examples of BWRs that use the Mark S containment. In those examples active safety systems and passive safety systems function independently and constitute in-depth hybrid safety (IDHS). The concept of the IDHS is also presented in the paper.     

掺铒光纤放大器(EDFA)及其应用

掺铒光纤放大器（EDFA）是WDM光通信网络最关键技术之一。论文对EDFA的工作原理，基本组成、特性、安全要求、应用方式及EDFA的发展趋势作了概括的阐述。     

不可抢占式EDF调度算法的可调度性分析

现有的不可抢占式EDF调度算法的可调度性分析判定条件限定实时任务的截止期必须等于其周期,限制了它的使用范围。论文突破这一限制,提出了更具一般性的可调度性分析判定充要条件。通过对可调度性判定充要条件的分析,提出了基于不可抢占式EDF调度算法的周期性实时系统可调度性分析算法。