采用基于M P I(消息传递库)的并行算法,在贴体网格下对带V形槽稳定器模型加力燃烧室紊流化学反应流场进行数值模拟,湍流模型采用k方程亚网格尺度模型,燃烧模型采用亚网格EBU模型,采用热通量辐射模型估算辐射通量。在程序设计中,采用动...采用基于M P I(消息传递库)的并行算法,在贴体网格下对带V形槽稳定器模型加力燃烧室紊流化学反应流场进行数值模拟,湍流模型采用k方程亚网格尺度模型,燃烧模型采用亚网格EBU模型,采用热通量辐射模型估算辐射通量。在程序设计中,采用动态内存分配、分区算法和多点重合交错网格系统,并行计算的结果与单机运行结果的对比表明计算结果是正确的,可以明显的提高运算效率,是解决复杂燃烧流动大规模数值模拟的有效手段。展开更多
Nowadays, we experience an abundance of Internet of Things middleware solutions that make the sensors and the actuators are able to connect to the Internet. These solutions, referred to as platforms to gain a widespre...Nowadays, we experience an abundance of Internet of Things middleware solutions that make the sensors and the actuators are able to connect to the Internet. These solutions, referred to as platforms to gain a widespread adoption, have to meet the expectations of different players in the IoT ecosystem, including devices [1]. Low cost devices are easily able to connect wirelessly to the Internet, from handhelds to coffee machines, also known as Internet of Things (IoT). This research describes the methodology and the development process of creating an IoT platform. This paper also presents the architecture and implementation for the IoT platform. The goal of this research is to develop an analytics engine which can gather sensor data from different devices and provide the ability to gain meaningful information from IoT data and act on it using machine learning algorithms. The proposed system is introducing the use of a messaging system to improve the overall system performance as well as provide easy scalability.展开更多
IoT applications are promising for future daily activities;therefore, the number of IoT connected devices is expected to reach billions in the coming few years. However, IoT has different application frameworks. Furth...IoT applications are promising for future daily activities;therefore, the number of IoT connected devices is expected to reach billions in the coming few years. However, IoT has different application frameworks. Furthermore, IoT applications require higher security standards. In this work, an IoT application framework is presented with a security embedded structure using the integration between message queue telemetry transport (MQTT) and user-managed access (UMA). The performance analysis of the model is presented. Comparing the model with existing models and different design structures shows that the model presented in this work is promising for a functioning IoT design model with security. The security in the model is a built-in feature in its structure. The model is built on recommended frameworks;therefore, it is ready for integration with other web standards for data sharing, which will help in making IoT applications integrated from different developing parties.展开更多
Internet of Things (IoT) environments are being deployed all over the globe. They have the potential to form solutions to applications, from small scale applications to national and international ones. Therefore, scal...Internet of Things (IoT) environments are being deployed all over the globe. They have the potential to form solutions to applications, from small scale applications to national and international ones. Therefore, scalability, performance, and security form a triangle of requirements that must be carefully set. Furthermore, IoT applications require higher security standards. A previously proposed IoT application framework with a security embedded structure using the integration between message queue telemetry transport (MQTT) and user-managed access (UMA) is analyzed in this work. The performance analysis of the model is presented. Comparing the model with existing models and different design structures shows that the model presented in this work is promising for a functioning IoT design model with security. The results and analysis showed that the built-in security model had performed better than models with other frameworks, especially with fog implementation.展开更多
CAN(Controller Area Network)总线技术的发展令人惊叹,基于CAN的车载总线实现ECU(Electronic Control Unit)分布式实时数据通讯,自由通信,总线仲裁。本文提出了在CAN协议基础上增加ECU间(Key)密钥分配与信息认证,简称MAC(Message Authe...CAN(Controller Area Network)总线技术的发展令人惊叹,基于CAN的车载总线实现ECU(Electronic Control Unit)分布式实时数据通讯,自由通信,总线仲裁。本文提出了在CAN协议基础上增加ECU间(Key)密钥分配与信息认证,简称MAC(Message Authentication Code,信息认证码)。本文会由浅入深阐述当前CAN总线协议基础上的MAC的工作原理与实现方式。展开更多
The Slingshot interconnect designed by HPE/Cray is becoming more relevant in high-performance computing with its deployment on the upcoming exascale systems.In particular,it is the interconnect empowering the first ex...The Slingshot interconnect designed by HPE/Cray is becoming more relevant in high-performance computing with its deployment on the upcoming exascale systems.In particular,it is the interconnect empowering the first exascale and highest-ranked supercomputer in the world,Frontier.It offers various features such as adaptive routing,congestion control,and isolated workloads.The deployment of newer interconnects sparks interest related to performance,scalability,and any potential bottlenecks as they are critical elements contributing to the scalability across nodes on these systems.In this paper,we delve into the challenges the Slingshot interconnect poses with current state-of-the-art MPI(message passing interface)libraries.In particular,we look at the scalability performance when using Slingshot across nodes.We present a comprehensive evaluation using various MPI and communication libraries including Cray MPICH,Open-MPI+UCX,RCCL,and MVAPICH2 on CPUs and GPUs on the Spock system,an early access cluster deployed with Slingshot-10,AMD MI100 GPUs and AMD Epyc Rome CPUs to emulate the Frontier system.We also evaluate preliminary CPU-based support of MPI libraries on the Slingshot-11 interconnect.展开更多
文摘采用基于M P I(消息传递库)的并行算法,在贴体网格下对带V形槽稳定器模型加力燃烧室紊流化学反应流场进行数值模拟,湍流模型采用k方程亚网格尺度模型,燃烧模型采用亚网格EBU模型,采用热通量辐射模型估算辐射通量。在程序设计中,采用动态内存分配、分区算法和多点重合交错网格系统,并行计算的结果与单机运行结果的对比表明计算结果是正确的,可以明显的提高运算效率,是解决复杂燃烧流动大规模数值模拟的有效手段。
文摘Nowadays, we experience an abundance of Internet of Things middleware solutions that make the sensors and the actuators are able to connect to the Internet. These solutions, referred to as platforms to gain a widespread adoption, have to meet the expectations of different players in the IoT ecosystem, including devices [1]. Low cost devices are easily able to connect wirelessly to the Internet, from handhelds to coffee machines, also known as Internet of Things (IoT). This research describes the methodology and the development process of creating an IoT platform. This paper also presents the architecture and implementation for the IoT platform. The goal of this research is to develop an analytics engine which can gather sensor data from different devices and provide the ability to gain meaningful information from IoT data and act on it using machine learning algorithms. The proposed system is introducing the use of a messaging system to improve the overall system performance as well as provide easy scalability.
文摘IoT applications are promising for future daily activities;therefore, the number of IoT connected devices is expected to reach billions in the coming few years. However, IoT has different application frameworks. Furthermore, IoT applications require higher security standards. In this work, an IoT application framework is presented with a security embedded structure using the integration between message queue telemetry transport (MQTT) and user-managed access (UMA). The performance analysis of the model is presented. Comparing the model with existing models and different design structures shows that the model presented in this work is promising for a functioning IoT design model with security. The security in the model is a built-in feature in its structure. The model is built on recommended frameworks;therefore, it is ready for integration with other web standards for data sharing, which will help in making IoT applications integrated from different developing parties.
文摘Internet of Things (IoT) environments are being deployed all over the globe. They have the potential to form solutions to applications, from small scale applications to national and international ones. Therefore, scalability, performance, and security form a triangle of requirements that must be carefully set. Furthermore, IoT applications require higher security standards. A previously proposed IoT application framework with a security embedded structure using the integration between message queue telemetry transport (MQTT) and user-managed access (UMA) is analyzed in this work. The performance analysis of the model is presented. Comparing the model with existing models and different design structures shows that the model presented in this work is promising for a functioning IoT design model with security. The results and analysis showed that the built-in security model had performed better than models with other frameworks, especially with fog implementation.
文摘CAN(Controller Area Network)总线技术的发展令人惊叹,基于CAN的车载总线实现ECU(Electronic Control Unit)分布式实时数据通讯,自由通信,总线仲裁。本文提出了在CAN协议基础上增加ECU间(Key)密钥分配与信息认证,简称MAC(Message Authentication Code,信息认证码)。本文会由浅入深阐述当前CAN总线协议基础上的MAC的工作原理与实现方式。
基金supported in part by the U.S.National Science Foundation under Grant Nos.1818253,1854828,1931537,and 2007991XRAC under Grant No.NCR-130002supported by the Office of Science of the U.S.Department of Energy under Contract No.DE-AC05-00OR22725.
文摘The Slingshot interconnect designed by HPE/Cray is becoming more relevant in high-performance computing with its deployment on the upcoming exascale systems.In particular,it is the interconnect empowering the first exascale and highest-ranked supercomputer in the world,Frontier.It offers various features such as adaptive routing,congestion control,and isolated workloads.The deployment of newer interconnects sparks interest related to performance,scalability,and any potential bottlenecks as they are critical elements contributing to the scalability across nodes on these systems.In this paper,we delve into the challenges the Slingshot interconnect poses with current state-of-the-art MPI(message passing interface)libraries.In particular,we look at the scalability performance when using Slingshot across nodes.We present a comprehensive evaluation using various MPI and communication libraries including Cray MPICH,Open-MPI+UCX,RCCL,and MVAPICH2 on CPUs and GPUs on the Spock system,an early access cluster deployed with Slingshot-10,AMD MI100 GPUs and AMD Epyc Rome CPUs to emulate the Frontier system.We also evaluate preliminary CPU-based support of MPI libraries on the Slingshot-11 interconnect.
