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Simulink与Windows程序间实时交互的研究 总被引:4,自引:0,他引:4
该文通过对实时交互仿真的研究,提出了一种实现Simulink仿真模型与外部Windows程序仿真模型实时交互的方法。该方法通过在S-函数的样板中加入使用共享内存的程序代码完成收发数据;然后编写能读写共享内存的外部程序进行数据读写;同时利用Windows消息机制协调仿真同步并实现仿真的实时性。基于上述方法。实现了Simulink仿真模型与外部Windows程序仿真模型的实时数据交互。仿真结果表明该方法能实现实时并获得较好的准确性,为实现Simulink仿真模型的重用及与其它仿真模型的实时交互提供了新的解决方案。 相似文献
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INFI-90是美国Bailay公司在N-90基础上推出的第三代分散型控制系统,也是集计算机技术、控制技术、通信技术和CRT显示技术于一体的新型过程控制装置.由于INFI-90的设备来源主要靠国外进口,许多从事自动控制的人员对它还比较陌生,在分散型控制系统的设计、安装、调试和运行维护方面还都缺乏经验,特别是大型大电机组的自动控制系统,受机组安全运行的限制,一般很难在现场对系统进行有效的试验研究.因此,很有必要建立一套采用INFI-90的控制系统仿真装置. 相似文献
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吸收式制冷系统将是制冷技术的重要发展方向。针对吸收式制冷系统管线长、设备复杂、监控点多、监控点分散的特点,设计了一种基于LabVIEW和CAN总线的分散式参数采集和控制系统。该系统采用CAN总线技术,开发了具有模拟量采集和控制的 CAN 节点,实现了对吸收式制冷系统的数据采集和参数控制,并利用上位机LabVIEW软件对采集到的数据进行运算处理,实现对系统运行状态的实时监控。采用CAN总线技术组成的控制系统,实现了控制系统的彻底分散,使系统结构简单、工作稳定,能实现多节点信号的实时通信与监控。 相似文献
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实时检测控制仪表,用光纤温度传感器测量连续非均相固定床微波催化反应系统的温度。由于系统自带软件基于MS D0S操作系统下,使用起来非常不便,所以目的是开发基于MS Windows平台的微波催化反应计算机实时控制系统。微波控制系统采用VB6.0编程,监控主界面包含操作员需要了解的所有数据。系统实现了对串口数据的实时采集,在wintdows环境实现了两级计算机实时控制系统,成功地对M100光纤温度传感器温控仪进行温度控制,取得较好的控制效果,具有一定的实际意义。 相似文献
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实时历史数据库中压缩技术的并行化研究 总被引:1,自引:0,他引:1
实时历史数据库系统需要极高的数据压缩速度,但传统的压缩算法都使用串行处理,数据压缩和文件读写都要耗费大量的时间.为了提高数据压缩速度,提出一种并行压缩算法,首先把待处理数据分成若干小块,然后通过对块数据压缩、解压缩、文件读写并发处理,充分发挥多核处理器的高性能.并设计出一种适合并行压缩算法的压缩数据存储文件格式和一个数据段信息循环链表,通过多线程编程技术来实现并行压缩算法.使用工程实测数据在多核处理器系统上的实验表明,并行压缩算法可以极大地提高数据压缩速度,满足实时历史数据库的需求. 相似文献
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文章简要介绍了BAILEY INFI-90的系统结构,论述了控制系统在安全可靠性方面存在的问题,并提出了可行的解决方案。 相似文献
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为了解决电力机车可控硅存在的动态击穿问题,提出设计可控硅整流装置实时监测系统,实时发现可控硅的技术状态的解决方案,并且针对监测系统的数据采集部分提出以FPGA作为多通道数据采集控制核心的设计方案,进行了具体设计,该系统有数据采集模块、数据存储器读写模块和数据通讯模块三大功能模块组成,与传统的以单片机为控制核心的多通道数据采集系统相比,该系统具有性能稳定可靠、实时性强、体积小、功耗低等优点。 相似文献
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非易失性存储器具有接近内存的读写速度,可利用其替换传统的存储设备,从而提升存储引擎的性能。但是,传统的存储引擎通常使用通用块接口读写数据,导致了较长的 I/O 软件栈,增加了软件层的读写延迟,进而限制了非易失性存储器的性能优势。针对这一问题,该文以 Ceph 大数据存储系统为基础,研究设计了基于非易失性存储器的新型存储引擎 NVMStore,通过内存映射的方式访问存储设备,根据非易失性存储器的字节可寻址和数据持久化特性,优化数据读写流程,从而减小数据写放大以及软件栈的开销。实验结果表明,与使用非易失性存储器的传统存储引擎相比,NVMStore能够显著提升 Ceph 的小块数据读写性能。 相似文献
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设计了一种基于STC15单片机的U盘实时海量数据采集系统。该系统利用USB接口芯片CH376对U盘进行读写操作,利用实时时钟芯片DS12887实时采集记录数据的时间,将采集到的海量数据以EXCEL文件形式存储在U盘中。实验结果表明,该方案能够采集、存储海量数据而且还兼顾成本低、通用性强、移动性好等优点,具有一定实用价值。 相似文献
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通过计算机USB接口对工业用卡进行命令控制、实时监控、数据通信等,是一种非常有效、十分实用的应用模式,可以解决大部分的实际应用问题。另外,以闪存为介质的存储盘具有体积小读写速度快、易扩展、功耗小、噪声低、能够在恶劣的环境下正常工作等优点。文章详细阐述了将两种技术融合为一体的图像数据存储与回读系统的设计,既解决了实际应用中的难题,而且具有参考价值。 相似文献
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Data outsourcing is plagued with several security and privacy concerns. Oblivious RAM (ORAM) can be used to address one of the many concerns, specifically to protect the privacy of data access pattern from outsourced cloud storage. This is achieved by simulating each original read or write operation with some read and write operations on both real and dummy data items. This paper proposes two single-server write-only ORAM schemes and one multi-server scheme, which simulate only the write operations and protect only the write pattern. The reduction in functionality however allows to build much simpler and efficient (in terms of communication/storage cost) ORAMs. Our schemes can achieve constant communication cost with acceptable storage usage. Write-only ORAM can be used in two situations: (i) only the write pattern is considered to contain sensitive information and needs protection. (ii) In outsourced data sharing, ORAM cannot be used to protect read pattern anyway due to access control issues, and Private Information Retrieval (PIR) has to be used instead. In this paper, we also study how to augment ORAM to support the use of PIR in the latter situation. 相似文献
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We study the performance of concurrency control algorithms in maintaining temporal consistency of shared data in hard real time systems. In our model, a hard real time system consists of periodic tasks which are either write only, read only or update transactions. Transactions may share data. Data objects are temporally inconsistent when their ages and dispersions are greater than the absolute and relative thresholds allowed by the application. Real time transactions must read temporally consistent data in order to deliver correct results. Based on this model, we have evaluated the performance of two well known classes of concurrency control algorithms that handle multiversion data: the two phase locking and the optimistic algorithms, as well as the rate monotonic and earliest deadline first scheduling algorithms. The effects of using the priority inheritance and stack based protocols with lock based concurrency control are also studied 相似文献
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The flash-based SSD is used as a tiered cache between RAM and HDD. Conventional schemes do not utilize the nonvolatile feature of SSD and cannot cache write requests. Writes are a significant, or often dominant, fraction of storage workloads. To cache write requests, the SSD cache should persistently and consistently manage its data and metadata, and guarantee no data loss even after a crash. Persistent cache management may require frequent metadata changes and causes high overhead. Some researchers insist that a nonvolatile persistent cache requires new additional primitives that are not supported by general SSDs in the market. We proposed a fully persistent read/write cache, which improves both read and write performance, does not require any special primitive, has a low overhead, guarantees the integrity of the cache metadata and the consistency of the cached data, even during a crash or power failure, and is able to recover the flash cache quickly without any data loss. We implemented the persistent read/write cache as a block device driver in Linux. Our scheme aims at virtual desktop infra servers. So the evaluation was performed with massive, real desktop traces of five users for ten days. The evaluation shows that our scheme outperforms an LRU version of SSD cache by 50% and the read-only version of our scheme by 37%, on average, for all experiments. This paper describes most of the parts of our scheme in detail. Detailed pseudo-codes are included in the Appendix. 相似文献