检索结果-内蒙古大学图书馆

Fast terminal sliding mode control for improved transient state power sharing between parallel VSCs in an autonomous microgrid under different loading conditions

引用

IET RENEWABLE POWER GENERATION 2020年第6期14卷 1063-1073页

作者： Prakash, Surya Mishra, Sukumar Indian Inst Technol Delhi Dept Elect Engn New Delhi 110016 India

For low-voltage autonomous microgrids, the essential goal is maintaining stable voltage and frequency throughout its network for the smooth operation of distributed loads. The other goal is to maintain proportionate power-sharing between multiple sources connected through voltage source converters (VSCs). For the particular case of a heavily loaded microgrid, any further increase in demand poses new problems. The VSCs proximate to the loads may overshoot beyond its maximum ratings. Owing to which the stability of the power supply, as well as the longevity of VSCs, may get compromised. Also, these sources provide power under varying composite loading conditions comprising both linear and non-linear loads resulting in unbalancing in its network. To overcome these problems, a decentralised fast terminal sliding mode control strategy for active power-sharing between parallel VSCs has been proposed. A detailed mathematical model based on Lyapunov's stability theory-based study is designed to establish the operating stability of the proposed controller. To validate the proposed control strategy, MATLAB-based simulation results are provided for possible loading scenarios. A comparative study for performance evaluation between the proposed controller and a conventional proportional -integral-based controller is further carried out. Finally, the performance of the proposed controller is also validated in real-time scenario.

关键词： field programmable gate arrays power grids power distribution control variable structure systems power generation control control system synthesis PI control distributed power generation power system stability voltage-source convertors power system transients Lyapunov methods voltage source converters heavily loaded microgrid power supply composite loading conditions nonlinear loads highly resistive network decentralised fast terminal sliding mode control strategy active power-sharing parallel VSCs mathematical model operating stability MATLAB-based simulation results field programmable gate array-based experimental conditions low-voltage autonomous microgrids stable voltage distributed loads transient state power sharing linear loads Lyapunov's stability theory-based study proportional-integral-based controller

来源：评论

学校读者我要写书评

暂无评论

Towards distributed Software Resilience in Asynchronous Many-Task Programming Models 10

Towards Distributed Software Resilience in Asynchronous Many...

引用

IEEE/ACM 10th workshop on Fault Tolerance for HPC at eXtreme Scale (FTXS)

作者： Gupta, Nikunj Mayo, Jackson R. Lemoine, Adrian S. Kaiser, Hartmut Indian Inst Technol Dept CSE Roorkee Uttar Pradesh India Sandia Natl Labs Livermore CA USA Louisiana State Univ Ctr Computat Technol Baton Rouge LA 70803 USA AMD Inc Austin TX USA STE AR Grp Noida India

ISBN: (纸本)9780738110806

Exceptions and errors occurring within mission critical applications due to hardware failures have a high cost. With the emerging Next Generation Platforms (NGPs), the rate of hardware failures will likely increase. Therefore, designing our applications to be resilient is a critical concern in order to retain the reliability of results while meeting the constraints on power budgets. In this paper, we discuss software resilience in AMTs at both local and distributed scale. We choose HPX to prototype our resiliency designs. We implement two resiliency APIs that we expose to the application developers, namely task replication and task replay. Task replication repeats a task n-times and executes them asynchronously. Task replay reschedules a task up to n-times until a valid output is returned. Furthermore, we expose algorithm based fault tolerance (ABFT) using user provided predicates (e.g., checksums) to validate the returned results. We benchmark the resiliency scheme for both synthetic and real world applications at local and distributed scale and show that most of the added execution time arises from the replay, replication or data movement of the tasks and not the boilerplate code added to achieve resilience.

关键词： software resilience parallel and distributed computing asynchronous many-task systems HPX

来源：评论

学校读者我要写书评

暂无评论

Exploring Accelerator and parallel Graph Algorithmic Choices for Temporal Graphs 11

Exploring Accelerator and Parallel Graph Algorithmic Choices...

引用

11th International workshop on Programming Models and Applications for Multicores and Manycores (PMAM)

作者： Rehman, Akif Ahmad, Masab Khan, Omer Univ Connecticut Storrs CT 06269 USA

ISBN: (纸本)9781450375221

Many real-world systems utilize graphs that are time-varying in nature, where edges appear and disappear with respect to time. Moreover, the weights of different edges are also a function of time. Various conventional graph algorithms, such as single source shortest path (SSSP) have been developed for time-varying graphs. However, these algorithms are sequential in nature and their parallel counterparts are largely overlooked. On the other hand, parallel algorithms for static graphs are implemented as ordered and unordered variants. Unordered implementations do not enforce local or global order for processing tasks in parallel, but incur redundant task processing to converge their solutions. These implementations expose parallelism at the cost of high redundant work. Relax-ordered implementations maintain local order through per-core priority queues to reduce the amount of redundant work, while exposing parallelism. Finally, strict-ordered implementations achieve the work efficiency of sequential version by enforcing a global order at the expense of high thread synchronizations. These parallel implementations are adopted for temporal graphs to explore the choices that provide optimal performance on different parallel accelerators. This work shows that selecting the optimal parallel implementation extracts geometric performance gain of 46.38% on Intel Xeon-40 core and 20.30% on NVidia GTX-1080 GPU. It is also shown that optimal implementation choices for temporal graphs are not always the same as their respective static graphs.

关键词： multicores graph algorithms static graphs temporal graphs performance scaling

来源：评论

学校读者我要写书评

暂无评论

EXPPO: EXecution Performance Profiling and Optimization for CPS Co-simulation-as-a-Service 23

EXPPO: EXecution Performance Profiling and Optimization for ...

引用

IEEE 23rd International Symposium on real-time distributed Computing (ISORC)

作者： Barve, Yogesh D. Neema, Himanshu Kang, Zhuangwei Sun, Hongyang Gokhale, Aniruddha Roth, Thomas Vanderbilt Univ Dept Elect Engn & Comp Sci Nashville TN 37212 USA NIST Smart Grid & Cyber Phys Syst Program Off Engn Lab Gaithersburg MD 20899 USA

ISBN: (纸本)9781728169583

A co-simulation may comprise several heterogeneous federates with diverse spatial and temporal execution characteristics. In an iterative time-stepped simulation, a federation exhibits the Bulk Synchronous parallel (BSP) computation paradigm in which all federates perform local operations and synchronize with their peers before proceeding to the next round of computation. In this context, the lowest performing (i.e., slowest) federate dictates the progression of the federation logical time. One challenge in co-simulation is performance profiling for individual federates and entire federations. The computational resource assignment to the federates can have a large impact on federation performance. Furthermore, a federation may comprise federates located on different physical machines as is the case for cloud and edge computing environments. As such, distributed profiling and resource assignment to the federation is a major challenge for operationalizing the co-simulation execution at scale. This paper presents the Execution Performance Profiling and Optimization (EXPPO) methodology, which addresses these challenges by using execution performance profiling at each simulation execution step and for every federate in a federation. EXPPO uses profiling to learn performance models for each federate, and uses these models in its federation resource recommendation tool to solve an optimization problem that improves the execution performance of the co-simulation. Using an experimental testbed, the efficacy of EXPPO is validated to show the benefits of performance profiling and resource assignment in improving the execution runtimes of co-simulations while also minimizing the execution cost.

关键词： cyber-physical systems distributed simulation cloud computing latency performance resource management gang scheduling

来源：评论

学校读者我要写书评

暂无评论

Evaluation of Stream Processing Frameworks

引用

IEEE TRANSACTIONS ON parallel AND distributed systems 2020年第8期31卷 1845-1858页

作者： van Dongen, Giselle Van den Poel, Dirk Univ Ghent B-9000 Ghent Belgium

The increasing need for real-time insights in data sparked the development of multiple stream processing frameworks. Several benchmarking studies were conducted in an effort to form guidelines for identifying the most appropriate framework for a use case. In this article, we extend this research and present the results gathered. In addition to Spark Streaming and Flink, we also include the emerging frameworks Structured Streaming and Kafka Streams. We define four workloads with custom parameter tuning. Each of these is optimized for a certain metric or for measuring performance under specific scenarios such as bursty workloads. We analyze the relationship between latency, throughput, and resource consumption and we measure the performance impact of adding different common operations to the pipeline. To ensure correct latency measurements, we use a single Kafka broker. Our results show that the latency disadvantages of using a micro-batch system are most apparent for stateless operations. With more complex pipelines, customized implementations can give event-driven frameworks a large latency advantage. Due to its micro-batch architecture, Structured Streaming can handle very high throughput at the cost of high latency. Under tight latency SLAs, Flink sustains the highest throughput. Additionally, Flink shows the least performance degradation when confronted with periodic bursts of data. When a burst of data needs to be processed right after startup, however, micro-batch systems catch up faster while event-driven systems output the first events sooner.

关键词： Benchmark testing Sparks Pipelines Throughput Storms Microsoft Windows Measurement Apache spark structured streaming apache flink apache kafka kafka streams distributed computing stream processing frameworks benchmarking big data

来源：评论

学校读者我要写书评

暂无评论

Issues and Algorithm of distributed Shared Memory

Issues and Algorithm of Distributed Shared Memory

引用

International Conference on Innovative Computing (ICIC)

作者： Mian Basam Ahmad Sundas Sagheer University of Management and Technology Lahore Pakistan

ISBN: (纸本)9781665400923

Internet of things is a rapidly growing industry, and there are more connected devices than humans. There are unlimited internet of things devices around us. The scope of these devices has increased manifold in recent years in different areas like healthcare, unmanned vehicles, automatic monitoring systems, and smart homes, etc. These connected devices produce lots of data that need to be processed to achieve the goal of automation in daily life. The cloud provides many centralized solutions to process data using powerful resources in real-time, but there could be latency issues due to increased network traffic. So a distributed solution is much needed to meet this growing demand of processing data in parallel. In this paper, we propose a distributed shared memory [18] abstraction for the internet of things that uses a graph-aware partitioning algorithm and uses smart message passing techniques to process data in distributed and parallel fashion [19].

关键词： Manifolds Message passing distributed databases Telecommunication traffic Smart homes Medical services real-time systems

来源：评论

学校读者我要写书评

暂无评论

CCSDS 131.2-B-1 Software Defined Radio receiver featuring GPU accelerators: up to 1000x with respect to CPU implementation.

CCSDS 131.2-B-1 Software Defined Radio receiver featuring GP...

引用

International workshop on Tracking, Telemetry and Command systems for Space Applications (TTC)

作者： Roberto Ciardi Gianluca Giuffrida Matteo Bertolucci Emanuele Pagani Luca Fanucci dept. of Information Engineering IngeniArs S.r.l. University of Pisa Via Caruso Pisa Italy IngeniArs S.r.l. Via Ponte a Piglieri Pisa Italy dept. of Information Engineering IngeniArs S.r.l. University of Pisa Via Ponte a Piglieri Pisa Italy dept. of Information Engineering University of Pisa Via Caruso Pisa Italy

ISBN: (数字)9781665487801

ISBN: (纸本)9781665487818

Nowadays the number of Earth Observation missions are exponentially increasing. Each satellite may embark payloads which produce a big amount of data, that need to be transmitted on-ground. To address large data transmissions, proper of this kind of missions, CCSDS 131.2-B standard has been developed. A limiting factor in the adoption of this communication system is represented by the complexity of the hardware required for running a receiver in real time. Software Defined Radio (SDR) receivers represent a potential low-cost solution when dealing with scientific data or low-medium-data rate. In this perspective, we present in this paper the implementation of an SDR dedicated to CCSDS 131.2-B. In particular, this software was designed following the Single Instruction Multiple Data paradigm to speed up the reception and data processing, exploiting the so called General Purpose-Graphic Processing Unit (GP-GPU). The entire software has been designed to be completely modular, i.e., allowing to easily add/modify each block in the reception chain. The preliminary results of the adoption of this SDR as a CCSDS 131.2-B receiver, has shown excellent performance, maintaining a throughput up to 10 MBaud for ACM 1-7. This throughput can be easily increased exploiting parallelism at decoder level, hence linearly increasing the SDR performance, up to the GP-GPU memory filling. The proposed solution is designed to be a game changer and a potential flagship killer for such missions wich requirements are relaxed in term of throughput.

关键词： Satellite broadcasting Receivers parallel processing Throughput Software real-time systems Telemetry

来源：评论

学校读者我要写书评

暂无评论

Live Demonstration: Multi-Laptop HEVC Encoding 52

Live Demonstration: Multi-Laptop HEVC Encoding

引用

IEEE International Symposium on Circuits and systems (ISCAS)

作者： Ahovainio, Sami Mercat, Alexandre Vanne, Jarno Tampere Univ Comp Sci Tampere Finland

ISBN: (纸本)9781728133201

This paper presents a demonstration setup for distributed real-time HEVC encoding on a multi-computer system. The demonstrated multi-level parallelization scheme is implemented in the practical Kvazaar open-source HEVC encoder. It allows Kvazaar to exploit parallelism at three levels: 1) Single Instruction Multiple Data (SIMD) optimized coding tools at the data level;2) Wavefront parallel Processing (WPP) and Overlapped Wavefront (OWF) parallelization strategies at the thread level;and 3) distributed slice encoding on multi-computer systems at the process level. This interactive demonstration allows visitors to gradually increase the degree of parallelism in Kvazaar and see the benefits of parallelization in live HEVC encoding. Exploiting all three levels of parallelism on a three-laptop setup speeds up Kvazaar by almost 21x over a non-parallelized single-core implementation of Kvazaar.

关键词： HEVC multi-level parallelization distributed HEVC encoding multi-computer systems

来源：评论

学校读者我要写书评

暂无评论

distributed power management with adaptive scheduling horizons for more electric aircraft

引用

INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY systems 2021年第PartA期126卷 106581-106581页

作者： Zhang, Yicheng Chen, Jian Yu, Yang ASTAR Inst Infocomm Res I2R 1 Fusionopolis Way21-01 Connexis Singapore 138632 Singapore Shandong Univ Minist Educ Key Lab Power Syst Intelligent Dispatch & Control Jinan 250061 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

A more electric aircraft is expected to have low emissions, decreased fuel consumption, high efficiency, and low maintenance costs. To fully enjoy those benefits, major technical obstacles must be overcome first. In terms of power management, an increasing number of power electronic components used in aircraft power systems and their ever-increasing functional sophistication will lead to high modeling and computational complexities, making real-time power management a daunting challenge. To address this challenge, in this paper we will first propose a novel architecture for real-time power scheduling, which allows a user to easily incorporate fault diagnosis, stability analysis and power scheduling together, and then present a locally tactical power scheduling strategy based on a Lagrangian relaxation, which allows a user to adopt different computation techniques to undertake local computations within sub-systems in parallel to ensure good scalability of the distributed strategy. Moreover, the power scheduling is calculated based on an adaptive scheduling horizon to further reduce the computational complexity. Simulations are carried out to illustrate the effectiveness of our proposed distributed architecture, in particular, the optimality of the solution and the balanced computational complexity.

关键词： Energy management Electrical power system distributed power scheduling Lagrangian relaxation Subgradient method Adaptive receding horizon

来源：评论

学校读者我要写书评

暂无评论

DADS: Dynamic Slicing Continuously-Running distributed Programs with Budget Constraints 2020

DADS: Dynamic Slicing Continuously-Running Distributed Progr...

引用

28th ACM Joint Meeting on European Software Engineering Conference and Symposium on the Foundations of Software Engineering (ESEC/FSE)

作者： Fu, Xiaoqin Cai, Haipeng Li, Li Washington State Univ Pullman WA 99164 USA Monash Univ Clayton Vic Australia

ISBN: (纸本)9781450370431

We present DADS, the first distributed, online, scalable, and cost-effective dynamic slicer for continuously-running distributed programs with respect to user-specified budget constraints. DADS is distributed by design to exploit distributed and parallel computing resources. With an online analysis, it avoids tracing hence the associated time and space costs. Most importantly, DADS achieves and maintains practical scalability and cost-effectiveness tradeoffs according to a given budget on analysis time by continually and automatically adjusting the configuration of its analysis algorithm on the fly via reinforcement learning. Against eight real-world Java distributed systems, we empirically demonstrated the scalability and cost-effectiveness merits of DADS. The open-source tool package of DADS with a demo video is publicly available.

关键词： distributed system dynamic slicing reinforcement learning

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：