关键词： 环境监测   NB-IoT技术   OneNET   低功耗   系统设计  

摘要： 针对传统环境监测系统功耗高、维护成本高、不能实时监测的弊端,研制了一种以单片机为主控制芯片的基于NB-IoT技术的环境温湿度监测系统,并对主控制器的工作流程及通信模块的工作方式进行优化,降低系统功耗。利用NB-IoT通信技术进行数据传输,将温湿度传感器采集的数据信息通过基站和核心网发送给云平台,运用中国移动物联网开放平台(OneNET平台)实现终端设备与应用的相互连接。通过平台的拓展功能实现网页界面及手机应用程序的设计,最终实现对环境参数的远程实时监测,提高使用便捷度。

关键词： 龙芯   VPX   Loongnix   数字信号处理   Python  

摘要： 文章设计了一种基于龙芯的数字信号处理实验平台。该平台采用国产化设计方案,基于VPX架构实现了平台功能可扩展;以龙芯处理器为主控芯片的信号处理板卡,集成了多种控制器和接口,将国产Linux系统Loongnix裁剪、配置、编译、移植到CPU上,以桌面方式管理平台内资源,便于实验操作;基于Python语言搭建实验环境,对音频信号进行了仿真加噪及滤波实验,获得良好结果,且测试时间、内存性能参数满足实验性能要求。该平台性能良好,具有操作便捷、扩展性强等特点,可有效降低核心芯片依赖进口问题,实现国产化替代。

关键词： Control systems   State feedback   Drives   Voltage control   DC motors   Velocity control   Torque   Constraints   electric drives   multithreaded state controller (MTSC)   servo drives   state feedback controller  

摘要： The article proposes a ground-breaking solution to address the challenge of imposing constraints in a full state feedback (FSF) control system. Its simplicity is comparable to the introduction of saturation blocks in the cascaded control system. In the developed control system, a given state variable is stabilized at the threshold value using a separate FSF controller. The overall controller consists then of a set of controllers, the main one with an external reference signal and auxiliary controllers with the internal references set to the desired limits to be imposed on each of the physical states of the investigated plant, operating in parallel fashion (hence the proposed name-multithreaded). This means that in each time instance, the processor executes all FSF controllers. Additionally, if the auxiliary integral states are implemented, a back-calculation algorithm is employed to keep the auxiliary states at the desired level for the controllers that are idling at a given time instance. The median of the calculated control signals is put through to the plant as a control signal. Such an elegant and straightforward way of handling constraints in the state feedback system has never been reported before and is currently patent pending. The proposed method is validated for a servo drive using hardware-in-the-loop setup. All the obtained results confirm technical feasibility of the controller structure and its ability to keep all the state variables within the required intervals.

关键词： Heterogeneous many-core architecture   Scratchpad memory   Direct memory access   Network-on-chip   Multithreaded application  

摘要： The heterogeneous many-core architecture plays an important role in the fields of high-performance computing and scientific computing. It uses accelerator cores with on-chip memories to improve performance and reduce energy consumption. Scratchpad memory (SPM) is a kind of fast on-chip memory with lower energy consumption compared with a hardware cache. However, data transfer between SPM and off-chip memory can be managed only by a programmer or compiler. In this paper, we propose a compiler-directed multithreaded SPM data transfer model (MSDTM) to optimize the process of data transfer in a heterogeneous many-core architecture. We use compile-time analysis to classify data accesses, check dependences and determine the allocation of data transfer operations. We further present the data transfer performance model to derive the optimal granularity of data transfer and select the most profitable data transfer strategy. We implement the proposed MSDTM on the GCC complier and evaluate it on Sunway TaihuLight with selected test cases from benchmarks and scientific computing applications. The experimental result shows that the proposed MSDTM improves the application execution time by 5.49x and achieves an energy saving of 5.16x on average.

关键词： Redundant multithreading   Fault tolerance   Soft error reliability   Software reliability  

摘要： Redundant multithreading (RMT) is an effective reliability solution that provides thread-level replication;however, it imposes additional overheads in terms of performance loss or energy consumption. Partial-RMT is an alternative solution that provides partial redundancy of an executing thread to reduce such overheads while trading off full coverage from faults. In this study, we propose a software-level RMT approach that offers lightweight replication of partial code regions within the same application process. Our software-level RMT approach is particularly suitable for applications with varying code criticality, where we determine the critical code regions by performing a fault injection campaign in addition to execution time profile analysis. Using the results of the previous step, the application programmer annotates the source code to indicate the specific code regions that should be executed redundantly without re-implementing the application program from scratch. Our lightweight software-level RMT tool improves the average silent data corruption (SDC) rate of 30 applications of the PolyBench benchmark suite by around 7.6x with average performance and energy consumption overheads of 22 and 37%, respectively, compared to the original version of the program.

关键词： STM32   意法半导体   超低功耗   电子产品   微控制器   全球同步   电池供电   设备运行  

摘要： 工程师在设计使用电池供电的电子产品时,最在意的一个指标就是功耗。众所周知,意法半导体(ST)的STM32超低功耗系列将功耗做到了极致。意法半导体中国区微控制器市场及应用总监曹锦东表示,近两年ST的收购主要聚焦于无线和AI,未来会有更多端侧设备运行AI算法,这些产品对功耗更为敏感。为此,近日ST在全球同步发布了其STM32系列超低功耗MCU的旗舰版产品--STM32U5。

关键词： 低功耗蓝牙   室内定位系统   蓝牙信号   设备   医院信息化  

摘要： 目的:开发一种基于低功耗蓝牙定位技术的手术室移动设备定位管理系统,用于追踪、查看和管理手术室内常用、贵重的麻醉设备。方法:本系统由硬件和软件组成,硬件主要由局域网交换机、蓝牙主机装置、蓝牙从机装置、服务器组成,软件主要是数据库、用户显示界面。利用局域网收集每个房间的蓝牙信号,通过服务器写入数据库,用户在电脑显示界面上搜索需要的设备即可显示位置。结果:本系统可以实现和获取医疗设备或仪器的工作位置,定位结果满足要求,系统工作稳定,界面一目了然,所有硬件维护少,体积小,充满1次电可以使用2年。结论:本系统解决了手术室内设备的定位问题,目前已在临床中使用,效果满意。

关键词： 信息产业   高科技企业   中国芯   生态建设   代替进口   自主化   尖端科技领域   国际竞争  

摘要： 在尖端科技领域,芯片的开发与制造一直是我国的短板。由于未掌握核心科技,在过去几年中,我国每年都要花费巨额外汇进口芯片,一旦被断供,国内高科技企业将会受到严重影响,切肤之痛让我们记忆深刻。这种“受制于人”的局面若无法得到改善,我国就很难在国际竞争中取得领先地位。发展“中国芯”,实现国产代替进口,走自主化道路,是一条虽难但必须要走的战略性道路。

关键词： LLVM   锁机制   多线程   原子性   申威处理器  

摘要： 基于申威处理器,在底层虚拟机(Low Level Virtual Machine, LLVM)编译器后端对锁机制提供编译支持,保证多线程环境下,对共享内存操作的原子性。锁机制研究与实现主要包括实现原子指令语义映射策略保证原子操作的原子性并在锁机制算法中加入对8位和16位数据类型的数据处理,实现锁机制在申威处理器上对小粒度数据类型的支持。基于并行计算机基准测试集NPB进行测试,在多线程环境下所有程序皆自校验通过。在16个线程下,Fortran语言程序平均加速比为11.91,最大加速比为15.73,C语言程序平均加速比为8.08,最大加速比为13.32。