In the real-time scheduling theory,schedulability and synchronization analyses are used to evaluate scheduling algorithms and real-time locking protocols,respectively,and the empirical synthesis experiment is one of t...In the real-time scheduling theory,schedulability and synchronization analyses are used to evaluate scheduling algorithms and real-time locking protocols,respectively,and the empirical synthesis experiment is one of the major methods to compare the performance of such analyses.However,since many sophisticated techniques have been adopted to improve the analytical accuracy,the implementation of such analyses and experiments is often time-consuming.This paper proposes a schedulability experiment toolkit for multiprocessor real-time systems(SET-MRTS),which provides a framework with infrastructures to implement the schedulability and synchronization analyses and the deployment of empirical synthesis experiments.Besides,with well-designed peripheral components for the input and output,experiments can be conducted easily and flexibly on SET-MRTS.This demonstration further proves the effectiveness of SET-MRTS in both functionality and availability.展开更多
With the development of technology,the number of English learners who opt for online learning has been increasing.In the past,students had a tendency to download English materials and watch online videos for improving...With the development of technology,the number of English learners who opt for online learning has been increasing.In the past,students had a tendency to download English materials and watch online videos for improving their English skills.Recently,thanks to a shift to online learning,students have been making more use of online synchronous oneon-one English classes to improve their English at leisure.Although this type of learning mode is becoming more and more popular,the study of the difficulties and challenges of English learners in such a field has been under-explored.This study attempts to use a qualitative approach to interview two English learners of different backgrounds to better understand the difficulties and challenges they encountered when using such a learning method.The two interviewees conclude points ranging from the learning aspect,distant feeling,signal delay,instability of the learning software and hardware that lead to technical problems.Certain measures to avoid the problems are also suggested in this paper.展开更多
To verify the performance of NR-PSS (Nonlinear Robust Power System Stabilizer) for large synchronous generators, field experiments were carried out on a 300 MW generator in Baishan Hydro Plant of Northeast China Power...To verify the performance of NR-PSS (Nonlinear Robust Power System Stabilizer) for large synchronous generators, field experiments were carried out on a 300 MW generator in Baishan Hydro Plant of Northeast China Power Grid. The experiment results show that NR-PSS can improve the generator damping and enhance system stability remarkably.展开更多
针对高压气枪在阵列中使用时的同步性能要求,介绍了气枪震源系统的组成原理、同步控制原理和影响同步性能的因素;详细阐述了气枪阵列中激发电路对电磁阀激发时刻的控制,及在可变延时控制电路的干预下实现高压气枪阵列的同步控制方法;提...针对高压气枪在阵列中使用时的同步性能要求,介绍了气枪震源系统的组成原理、同步控制原理和影响同步性能的因素;详细阐述了气枪阵列中激发电路对电磁阀激发时刻的控制,及在可变延时控制电路的干预下实现高压气枪阵列的同步控制方法;提出了在实验室条件下开展同步性能测试的方法,并以容积150 in 3高压气枪为例,组建了实验室条件下的高压气枪同步性能测试系统,得到连续20组测试数据,通过分析得到其激发的时间偏差在±0.498 ms内,符合勘探同步性需求,激发一致性较好,气枪工作稳定,可用于气枪阵列的组建。展开更多
基金supported by the National Natural Science Foundation of China under Grant No.61802052the Fundamental Research Funds for the Central Universities under Grant No.A030202063008085the China Postdoctoral Science Foundation Funded Project under Grant No.2017M612947。
文摘In the real-time scheduling theory,schedulability and synchronization analyses are used to evaluate scheduling algorithms and real-time locking protocols,respectively,and the empirical synthesis experiment is one of the major methods to compare the performance of such analyses.However,since many sophisticated techniques have been adopted to improve the analytical accuracy,the implementation of such analyses and experiments is often time-consuming.This paper proposes a schedulability experiment toolkit for multiprocessor real-time systems(SET-MRTS),which provides a framework with infrastructures to implement the schedulability and synchronization analyses and the deployment of empirical synthesis experiments.Besides,with well-designed peripheral components for the input and output,experiments can be conducted easily and flexibly on SET-MRTS.This demonstration further proves the effectiveness of SET-MRTS in both functionality and availability.
文摘With the development of technology,the number of English learners who opt for online learning has been increasing.In the past,students had a tendency to download English materials and watch online videos for improving their English skills.Recently,thanks to a shift to online learning,students have been making more use of online synchronous oneon-one English classes to improve their English at leisure.Although this type of learning mode is becoming more and more popular,the study of the difficulties and challenges of English learners in such a field has been under-explored.This study attempts to use a qualitative approach to interview two English learners of different backgrounds to better understand the difficulties and challenges they encountered when using such a learning method.The two interviewees conclude points ranging from the learning aspect,distant feeling,signal delay,instability of the learning software and hardware that lead to technical problems.Certain measures to avoid the problems are also suggested in this paper.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50525721, 59837270)
文摘To verify the performance of NR-PSS (Nonlinear Robust Power System Stabilizer) for large synchronous generators, field experiments were carried out on a 300 MW generator in Baishan Hydro Plant of Northeast China Power Grid. The experiment results show that NR-PSS can improve the generator damping and enhance system stability remarkably.
文摘针对高压气枪在阵列中使用时的同步性能要求,介绍了气枪震源系统的组成原理、同步控制原理和影响同步性能的因素;详细阐述了气枪阵列中激发电路对电磁阀激发时刻的控制,及在可变延时控制电路的干预下实现高压气枪阵列的同步控制方法;提出了在实验室条件下开展同步性能测试的方法,并以容积150 in 3高压气枪为例,组建了实验室条件下的高压气枪同步性能测试系统,得到连续20组测试数据,通过分析得到其激发的时间偏差在±0.498 ms内,符合勘探同步性需求,激发一致性较好,气枪工作稳定,可用于气枪阵列的组建。
