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951.
为预付费采暖系统设计了用于供热中心主管部门依卡购热的IC卡购热系统,IC卡读写器主控芯片为单片机STC89C52RC,通过串口(或USB接口)与上位机通信,上位机软件采用LabVIEW开发,使用LabSQL实现了对数据库的管理。  相似文献   
952.
等离子裂解煤制乙炔工艺是一种处于试验阶段的新型煤化工路线。系统的节能、平稳运行对新工艺的经济性和可行性至关重要。本文基于夹点技术对煤制乙炔全流程进行了用能分析和诊断,得出了最优的能量利用目标;在考虑实际约束的情况下提出2套换热方案。进一步,利用路径法得出两套换热方案的传递函数,由此建立了动态仿真模型,进而得到2套换热方案对扰动的动态响应特性;在对传递函数进行分析的基础上,发现影响换热网络动态性能的公用工程位置和单个换热器换热充分度2个因素。结果表明,方案1和方案2均具有较好的动态性能,能够保障节能方案的平稳运行。  相似文献   
953.
面向P2P特定信息的传播动力学模型研究   总被引:1,自引:1,他引:0  
丁军平  蔡皖东 《计算机科学》2011,38(11):96-99,113
鉴于P2P特定信息传播与传染病传播的相似性,传播动力学是P2P特定信息传播的最新研究方向。针对现有传播动力学模型都不能准确模拟P2P特定信息传播过程的问题,对现有的SEIR传播动力学模型进行改进,建立了SEInR模型。该模型的主要特点包括:将传统的感染者(I)分为n个子类,每个子类赋予不同的模型参数;建立潜伏者(E)与移除者(R)之间的转换关系等。应用现代数学中的矩阵理论,得到SEInR模型的基本再生数计算公式,并对其进行分析。仿真结果表明,所提出的SEInR模型比传统SEIR模型能够更准确地模拟P2P特定信息传播过程,得到的基本再生数计算公式能够准确反映P2P特定信息的传播阂值。  相似文献   
954.
Ensuring model quality is a key success factor in many computer science areas, and becomes crucial in recent software engineering paradigms like the one proposed by model-driven software development. Tool support for measurements and redesigns becomes essential to help developers improve the quality of their models. However, developing such helper tools for the wide variety of (frequently domain specific) visual notations used by software engineers is a hard and repetitive task that does not take advantage from previous developments, thus being frequently forgotten.In this paper we present our approach for the visual specification of measurements and redesigns for Domain Specific Visual Languages (DSVLs). With this purpose, we introduce a novel DSVL called SLAMMER that contains generalisations of some of the more used types of internal product measurements and redesigns. The goal is to facilitate the task of defining measurements and redesigns for any DSVL, as well as the generation of tools from such specification reducing or eliminating the necessity of coding. We rely on the use of visual patterns for the specification of the relevant elements for each measurement and redesign type. In addition, SLAMMER allows the specification of redesigns either procedurally or by means of graph transformation rules. These redesigns can be triggered when the measurements reach a certain threshold.These concepts have been implemented in the meta-modelling tool AToM3. In this way, when a DSVL is designed, it is possible to specify measurements and redesigns that will become available in the final modelling environment generated for the language. As an example, we show a case study in the web modelling domain.  相似文献   
955.
The simplicity of regular mesh topology Network on Chip (NoC) architecture leads to reductions in design time and manufacturing cost. A weakness of the regular shaped architecture is its inability to efficiently support cores of different sizes. A proposed way in literature to deal with this is to utilize the region concept, which helps to accommodate cores larger than the tile size in mesh topology NoC architectures. Region concept offers many new opportunities for NoC design, as well as provides new design issues and challenges. One of the most important among these is the design of an efficient deadlock free routing algorithm. Available adaptive routing algorithms developed for regular mesh topology cannot ensure freedom from deadlocks. In this paper, we list and discuss many new design issues which need to be handled for designing NoC systems incorporating cores larger than the tile size. We also present and compare two deadlock free routing algorithms for mesh topology NoC with regions. The idea of the first algorithm is borrowed from the area of fault tolerant networks, where a network topology is rendered irregular due to faults in routers or links, and is adapted for the new context. We compare this with an algorithm designed using a methodology for design of application specific routing algorithms for communication networks. The application specific routing algorithm tries to maximize adaptivity by using static and dynamic communication requirements of the application. Our study shows that the application specific routing algorithm not only provides much higher adaptivity, but also superior performance as compared to the other algorithm in all traffic cases. But this higher performance for the second algorithm comes at a higher area cost for implementing network routers.  相似文献   
956.
A suitable combination of materials for sheltering a system from a sudden change of environmental temperature has been theoretically studied. The protective composite wall consists of two materials. An insulating material is placed on the outer surface, while, for the inner surface, materials that have good heat storage properties but negligible heat transfer resistance are chosen. The results show that by replacing some of the insulation material with a heat storage material, the temperature of the protected system can be maintained at a considerably lower level. Although the optimal thickness ratio X depends on the Biot number, Fourier number, and on the heat capacity ratio K C, for a large number of thermal protection cases, the approximation X = 0.45 yields practically the minimum progress of the transient. If the Biot number is sufficiently small, it is better to replace all of the insulation material with a good heat storage material.  相似文献   
957.
To meet both flexibility and performance requirements, particularly when implementing high-end real-time image/video processing algorithms, the paper proposes to combine the application specific instruction-set processor (ASIP) paradigm with the reconfigurable hardware one. As case studies, the design of partially reconfigurable ASIP (r-ASIP) architectures is presented for two classes of algorithms with widespread diffusion in image/video processing: motion estimation and retinex filtering. Design optimizations are addressed at both algorithmic and architectural levels. Special processor concepts used to trade-off performance versus flexibility and to enable new features of post-fabrication configurability are shown. Silicon implementation results are compared to known ASIC, DSP or reconfigurable designs; the proposed r-ASIPs stand for their better performance–flexibility figures in the respective algorithmic class.
Luca FanucciEmail:

Sergio Saponara   got the Laurea degree, cum laude, and the Ph.D. in Electronic Engineering from the University of Pisa in 1999 and 2003, respectively. In 2002, he was with IMEC, Leuven (B), as Marie Curie Research Fellow. Since 2001, he collaborates with Consorzio Pisa Ricerche-TEAM in Pisa. He is senior researcher at the University of Pisa in the field of VLSI circuits and systems for telecom, multimedia, space and automotive applications. He is co-author of more than 80 scientific publications. He holds the chair of electronic systems for automotive and automation at the Faculty of Engineering. Michele Casula   received the Laurea degree in Electronic Engineering from the University of Pisa in 2005. Since 2006, he is pursuing a Ph.D. degree in Information Engineering at the same university. His current interests involve VLSI circuits design, computer graphics, and Network-on-Chips. Luca Fanucci    received the Laurea degree and the Ph.D. degree in Electronic Engineering from the University of Pisa in 1992 and 1996, respectively. From 1992 to 1996, he was with ESA/ESTEC, Noordwijk (NL), as a research fellow. From 1996 to 2004, he was a senior researcher of the Italian National Research Council in Pisa. He is Professor of Microelectronics at the University of Pisa. His research interests include design methodologies and hardware/software architectures for integrated circuits and systems. Prof. Fanucci has co-authored more than 100 scientific publications and he holds more than ten patents.  相似文献   
958.
集中供热是近年来大力推广的节能和环保措施。本文介绍一种无线数据传输网络控制系统,它可用来对大型集中供热系统中的换热站进行遥测、遥信和遥控。实现换热站的无人值守,保证设备的安全运行。具体介绍了换热站的工艺流程、无线三遥控制系统的构成、工作原理、软件设计以及应用效果。  相似文献   
959.
This paper presents novel algorithmic and architectural solutions for real-time and power-efficient enhancement of images and video sequences. A programmable class of Retinex-like filters, based on the separation of the illumination and reflectance components, is proposed. The dynamic range of the input image is controlled by applying a suitable non-linear function to the illumination, while the details are enhanced by processing the reflectance. An innovative spatially recursive rational filter is used to estimate the illumination. Moreover, to improve the visual quality results of two-branch Retinex operators when applied to videos, a novel three-branch technique is proposed which exploits both spatial and temporal filtering. Real-time implementation is obtained by designing an Application Specific Instruction-set Processor (ASIP). Optimizations are addressed at algorithmic and architectural levels. The former involves arithmetic accuracy definition and linearization of non-linear operators; the latter includes customized instruction set, dedicated memory structure, adapted pipeline, bypasses, custom address generator, and special looping structures. The ASIP is synthesized in standard-cells CMOS technology and its performances are compared to known Digital signal processor (DSP) implementations of real-time Retinex filters. As a result of the comparison, the proposed algorithmic/architectural design outperforms state-of-art Retinex-like operators achieving the best trade-off between power consumption, flexibility, and visual quality.
Giovanni RamponiEmail:

Sergio Saponara   is a Research Scientist and Assistant Professor at the University of Pisa. He was born in Bari, Italy, in 1975. He received the Electronic Engineering degree cum laude and the Ph.D. in Information Engineering, both from Pisa University, in 1999 and 2003, respectively. Since 2001 he collaborates with Consorzio Pisa Ricerche, Italy and in 2002 he was with IMEC, Belgium as Marie Curie research fellow. His research and teaching interests include electronic circuits and systems for multimedia, telecom and automation. He co-authored more than 40 papers including journals, conferences and patents. Luca Fanucci   is Associate Professor of Microelectronics at the University of Pisa. He was born in Montecatini, Italy, in 1965. He received the Doctor Engineer degree and the Ph.D. in Electronic Engineering from the University of Pisa in 1992 and 1996, respectively. From 1992 to 1996, he was with the European Space Agency's Research and Technology Center, Noordwijk, The Netherlands, and from 1996 to 2004 he was a Research Scientist of the Italian National Research Council in Pisa. His research interests include design technologies for integrated circuits and systems, with emphasis on system-level design, hardware/software co-design and low-power. He co-authored more than 100 journal/conference papers and holds more than 10 patents. Stefano Marsi   was born in Trieste, Italy, in 1963. He received the Doctor Engineer degree in Electronic Engineering (summa cum laude) in 1990 and the Ph.D. degree in 1994. Since 1995 he has held the position of researcher in the Department of Electronics at the University of Trieste where he is the teacher of courses in electronic field. His research interests include non-linear operators for image and video processing and their realization through application specific electronics circuits. He is author or co-author of more than 40 papers in international journals, proceedings of international conferences or contributions in books. Giovanni Ramponi   is Professor of Electronics at the Department of Electronics of the University of Trieste, Italy. His research interests include nonlinear digital signal processing, and the enhancement and feature extraction in images and image sequences. Prof. Ramponi has been an Associate Editor of the IEEE Signal Processing Letters and of the IEEE Transactions on Image Processing; presently is an AE of the SPIE Journal of Electronic Imaging. He has participated in various EU and National Research Projects. He is the co-inventor of various pending international patents and has published more than 140 papers in international journals and conference proceedings, and as book chapters. Prof. Ramponi contributes to several undergraduate and graduate courses on digital signal processing.   相似文献   
960.
催化裂化提升管反应器数学模型基本上都是基于平推流反应器的假设建立起来的,但是由于其内部流动、传热以及反应过程非常复杂、偏离平推流较大,所以在模型的实际应用中必须用装置因数去校正,表现出较强的经验性,为了改变这种状况,本文通过研究分析,提出了对催化裂化提升管反应器进行多维微分模拟的研究方法,从根本上把反应器结构尺寸、物流入口条件,流动特征及传热特征等影响考虑进来,把流动、传热、传质、裂化反应以及湍流脉动作用全部纲入模型中,建立催化裂化提升管反应器的流动反应综合模型,通过对模型的求解,可以得到提升管反应器内催化剂颗粒及油气的速度分布、温度分布以及组分分布,从而揭示工业提升管反应器内的化学工程信息。这些数据对工业提升管反应器的设计、操作优化及新技术的实施都是十分重要的。  相似文献   
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