MCF: A Metamodeling-Based Component Composition Framework—Composing SystemC IPs for Executable System Models

Reusing Intellectual Property (IP)-cores accompanied by automated generation of the glue-logic, and automated composability checks can help designers to create efficient system-level models quickly and correctly for fast design space exploration. Furthermore, with the rise of multiple transaction level and register-transfer level abstractions, constructing models with mixed abstraction levels is also important. A framework that allows designers to: 1) describe the structure of components, their interfaces, and their interactions, with a semantically rich visual frontend; 2) automatically select IPs from a component library-based on sound-type theoretic principles; and 3) perform constraint based checks for composability, is highly desirable in this context. A metamodel based framework brings forth further advantages. It helps in: 1) providing rigorous semantics to the visual models; 2) imposing restrictions on the model and on interactions between components through constraints expressed in a constraint language; and 3) enabling type-checking and inference-based facilities. Furthermore, using XML-based schemas to store and process meta-information about the IPs as well as the schematic visual model, allows for an IP selection and integration methodology using existing XML processing tools. With these in mind, we present MCF, a metamodeling-based component composition framework for SystemC-based IP core composition at multiple and mixed abstraction levels, with all the advantages stated above.     

Enforcing Cooperative Resource Sharing in Untrusted P2P Computing Environments

Peer-to-Peer (P2P) computing is widely recognized as a promising paradigm for building next generation distributed applications. However, the autonomous, heterogeneous, and decentralized nature of participating peers introduces the following challenge for resource sharing: how to make peers profitable in the untrusted P2P environment? To address the problem, we present a self-policing and distributed approach by combining two models: PET, a personalized trust model, and M-CUBE, a multiple-currency based economic model, to lay a foundation for resource sharing in untrusted P2P computing environments. PET is a flexible trust model that can adapt to different requirements, and provides the solid support for the currency management in M-CUBE. M-CUBE provides a novel self-policing and quality-aware framework for the sharing of multiple resources, including both homogeneous and heterogeneous resources. We evaluate the efficacy and performance of this approach in the context of a real application, a peer-to-peer Web server sharing. Our results show that our approach is flexible enough to adapt to different situations and effective to make the system profitable, especially for systems with large scale.     

CLIF, a framework based on Fractal for flexible, distributed load testing

The context of this work is performance evaluation of IT systems based on load testing. It typically consists in generating a flow of requests on a system under test, and to measure response times, request throughput, or computing resource usage. A quick overview of available load testing platforms shows that there exist hundreds of such platforms, including in the open source domain. However, many testers still tend to develop their own ad hoc load testing tooling. Why? This paper starts by looking for possible answers to this question, in order to introduce the CLIF load injection framework, which intends not to be yet another load testing platform. Based on the Fractal component model, the CLIF open source project aims at addressing key issues such as flexibility, adaptation, and scalability. We give here details about CLIF’s architecture and associated tools as well as some feedback from a bunch of practical utilizations.     

SML-Sys: a functional framework with multiple models of computation for modeling heterogeneous system

System-on-Chip and other complex distributed hardware/software systems contain heterogeneous components. High-level modeling of such systems require frameworks that provide designers with the ability to express concepts of models of computation (MoC)s as modeling constructs. Many system-level modeling frameworks and corresponding modeling notations such as Ptolemy II and SystemC-H facilitate multi-MoC modeling but are based on imperative programming languages (C++, Java, etc). In such frameworks, the computation and communication aspects between the components of models get intertwined thereby hindering its amenability to formal analysis. In this work, we illustrate function-based semantic definitions of MoCs, which are formulated in a functional framework called SML-Sys. We illustrate through a number of examples how to create system models using this functional programming paradigm.     

Overview of the MPEG Reconfigurable Video Coding Framework

Video coding technology in the last 20 years has evolved producing a variety of different and complex algorithms and coding standards. So far the specification of such standards, and of the algorithms that build them, has been done case by case providing monolithic textual and reference software specifications in different forms and programming languages. However, very little attention has been given to provide a specification formalism that explicitly presents common components between standards, and the incremental modifications of such monolithic standards. The MPEG Reconfigurable Video Coding (RVC) framework is a new ISO standard currently under its final stage of standardization, aiming at providing video codec specifications at the level of library components instead of monolithic algorithms. The new concept is to be able to specify a decoder of an existing standard or a completely new configuration that may better satisfy application-specific constraints by selecting standard components from a library of standard coding algorithms. The possibility of dynamic configuration and reconfiguration of codecs also requires new methodologies and new tools for describing the new bitstream syntaxes and the parsers of such new codecs. The RVC framework is based on the usage of a new actor/ dataflow oriented language called CAL for the specification of the standard library and instantiation of the RVC decoder model. This language has been specifically designed for modeling complex signal processing systems. CAL dataflow models expose the intrinsic concurrency of the algorithms by employing the notions of actor programming and dataflow. The paper gives an overview of the concepts and technologies building the standard RVC framework and the non standard tools supporting the RVC model from the instantiation and simulation of the CAL model to software and/or hardware code synthesis.     

Optimal Query-Driven Data Forwarding for Delay-Sensitive Wireless Sensor Networks

Most of existing works on the topic of real-time routing for wireless sensor networks suffer from void forwarding paths (cannot reach the destination, but have to backtrack) and time overhead of handling isolated nodes. Designing a desired real-time data forwarding protocol as well as achieving a good tradeoff between real time and energy efficiency (as well as energy balance) for delay-sensitive wireless sensor networks remains a crucial and challenging issue. In this paper, we propose an optimal query-driven data forwarding framework that each sensor gets its optimal data forwarding paths (directed acyclic graphs) based on the query messages flooded by the base station without extra overhead. Furthermore, First Forwarding Nodes and Second Forwarding Nodes schemes are developed for data forwarding. In addition, two greedy distributed data forwarding algorithms are provided base on hybrid link cost model trying to achieve energy balance and congestion avoidance in data forwarding. Our framework is fully distributed and practical to implement, as well as robust and scalable to topological changes. The extensive simulations show that our framework has significantly outperformed the existing routing protocols in terms of real time and energy efficiency.     

Generation of component level fault models for MEMS

Component level (nodal) simulations have been proposed to both implement closed loop simulation of complete microsystems to support the migration to shorter design cycles and implement fault models of micromechanical components. Within such a simulation environment, library cells in the form of behavioural models are used for the basic components of microelectromechanical (MEM) transducers, such as beams, plates, comb-drives and membranes. This paper presents both methodologies to generate the model parameters required for the implementation of accurate component fault models and simulation results from representative defective structures in a MEMS product.     

Closed-Loop Modeling in Future Automation System Engineering and Validation

This paper presents a new framework for design and validation of industrial automation systems based on systematic application of formal methods. The engineering methodology proposed in this paper is based on the component design of automated manufacturing systems from intelligent mechatronic components. Foundations of such componentspsila information infrastructure are the new IEC 61499 architecture and the automation object concept. It is illustrated in this paper how these architectures, in conjunction with other advanced technologies, such as Unified Modeling Language, Simulink, and net condition/event systems, form a framework that enables pick-and-place design, simulation, formal verification, and deployment with the support of a suite of software tools. The key feature of the framework is the inherent support of formal validation techniques achieved on account of automated transformation among different system models. The paper appeals to developers of automation systems and automation software tools via showing the pathway to improve the system development practices by combining several design and validation methodologies and technologies.     

AADL流模型与实时演算模型的转换方法研究

在分布式综合航空电子信息流时延分析的过程中,时间触发(TT)流量可以直接在体系结构分析与设计语言的流时延分析框架下进行分析,而对速率约束(RC)流量的分析必须借助其他专用的分析模型,即实时演算(RTC)模型。因此,必须实现基于模型意义一致性的从AADL模型向RTC模型的转换,并且使转换后的模型可以利用RTC分析工具快速获取必要的时延参数,文章对此进行了研究。     

Leveraging component-based software engineering with Fraclet

Component-based software engineering has achieved wide acceptance in the domain of software engineering by improving productivity, reusability and composition. This success has also encouraged the emergence of a plethora of component models. Nevertheless, even if the abstract models of most of lightweight component models are quite similar, their programming models can still differ a lot. This drawback limits the reuse and composition of components implemented using different programming models. The contribution of this article is to introduce Fraclet as a programming model common to several lightweight component models. This programming model is presented as an annotation framework, which allows the developer to annotate the program code with the elements of the abstract component model. Then, using a generative approach, the annotated program code is completed according to the programming model of the component model to be supported by the component runtime environment. This article shows that this annotation framework provides a significant simplification of the program code by removing all dependencies on the component model interfaces. These benefits are illustrated with the Fractal and OpenCOM component models.     

An Integrated CAD Methodology for Evaluating MOSFET and Parasitic Extraction Models and Variability

An integrated computer-aided design (CAD) framework for evaluating MOSFET and layout parasitic extraction (LPE) models and circuit simulators used in the timing and power analysis of CMOS products is presented. This unified CAD methodology builds a step-wise understanding of the underlying parameter values in the models and their impact on circuit performance. A number of circuit experiments are included to extract the contributions of key MOSFET parameters and physical layout sensitive parasitic elements from circuit simulation results. This CAD setup thus allows easy and detailed comparison of different technologies, device models, and LPE tools to prevent possible bugs in the software as well as inaccuracies in device and parasitic models and timing tools. The software code to carry out the circuit simulations, analysis, and display of the results in an automated fashion has been specifically developed to support this framework. Some of the experiments designed for this work are also placed on the product chip for model-to-hardware correlation. The comparison of the hardware data to the model predictions points to the sources of any discrepancies and aids in tuning the product design to reflect changes in the technology as part of an overall design for manufacturing (DFM) platform     

Development of Behavioural Models for Mechanically Loaded Microcantilevers and Beams

From a modelling viewpoint MEMS are very complex structures. The development of full mathematical models is an extremely challenging problem. Some of the methods, assumptions and simplifications commonly used when modelling macroengineering structures may not be applied to real MEMS. Furthermore applying well-known behavioural models developed for macrostructures to microdevices has proved to be questionable if not inappropriate. Thus alternative approaches need to be used and new models need to be developed. This paper presents mathematical models of mechanical behaviour of micromachined cantilevers and beams on supports under uniform or concentrated load. The models were extracted from finite element simulation data using dimensional analysis.Maryna Lishchynska received a M.Sc. in Applied mathematics from Lviv Polytechnic State University, Ukraine in 1993, and was awarded Ph.D. in Technical Sciences from the Institute of Physics and Mechanics of the National Academy of Sciences of Ukraine in 2000. Dr. Lishchynska’s Ph.D. research was in the area of deformable solid mechanics (fatigue fracture mechanics). During 1993–2001 she worked as a research scientist on fracture mechanics problems for the Institute of Physics and Mechanics of the National Academy of Sciences of Ukraine and published a range of papers. Maryna joined the Tyndall National Institute (Cork, Ireland) in 2003 as a post-doctoral researcher in the Computational Modelling Group. She is currently involved in development of behavioural models of microsystems structures.Nicolas Cordero received Ing. Superior de Telecomunicación at Polytechnical University of Madrid. He is at Tyndal National Institute (Cork, Ireland) since 1990. Here he has worked on numerical modelling of electronic and optoelectronic devices based on compound semiconductors (MESFETs, HEMTs, Schottky diodes, Lasers and LEDs). He has also worked on modelling of photo-voltaic (PV) systems. Since 2001 Nicolas is at the Computational Modelling Group working on thermal and thermo-mechanical modelling, including finite element modelling of MEMS.Orla Slattery obtained a B.E. in civil engineering from University College Cork in 1989, M.Eng.Sc (civil engineering) in 1991 and M.Eng.Sc (electronics) 1998. In 1991 she joined the Interconnection and Packaging Group at NMRC where she was responsible for simulation and characterisation of thermal and thermomechanical issues in electronics components and systems. Since 1999 she has been working as a research scientist with the Computational Modelling Group in NMRC. She has participated in a number of European Union and Irish Government funded projects as well as providing services to Irish and European Industry. Her current research interests include the application of computational simulation tools to the solution of thermal and thermomechanical problems in microelectronics components and systems. She has published a range of papers in these areas. She is also involved in modelling and simulation of MEMS and is currently vice-chair of the EU funded Network of Excellence on Design for Micro and Nano manufacture, PATENT- DfMM.     

Speech and Language Processing for Multimodal Human-Computer Interaction

In this paper, we describe our recent work at Microsoft Research, in the project codenamed Dr. Who, aimed at the development of enabling technologies for speech-centric multimodal human-computer interaction. In particular, we present in detail MiPad as the first Dr. Who's application that addresses specifically the mobile user interaction scenario. MiPad is a wireless mobile PDA prototype that enables users to accomplish many common tasks using a multimodal spoken language interface and wireless-data technologies. It fully integrates continuous speech recognition and spoken language understanding, and provides a novel solution to the current prevailing problem of pecking with tiny styluses or typing on minuscule keyboards in today's PDAs or smart phones. Despite its current incomplete implementation, we have observed that speech and pen have the potential to significantly improve user experience in our user study reported in this paper. We describe in this system-oriented paper the main components of MiPad, with a focus on the robust speech processing and spoken language understanding aspects. The detailed MiPad components discussed include: distributed speech recognition considerations for the speech processing algorithm design; a stereo-based speech feature enhancement algorithm used for noise-robust front-end speech processing; Aurora2 evaluation results for this front-end processing; speech feature compression (source coding) and error protection (channel coding) for distributed speech recognition in MiPad; HMM-based acoustic modeling for continuous speech recognition decoding; a unified language model integrating context-free grammar and N-gram model for the speech decoding; schema-based knowledge representation for the MiPad's personal information management task; a unified statistical framework that integrates speech recognition, spoken language understanding and dialogue management; the robust natural language parser used in MiPad to process the speech recognizer's output; a machine-aided grammar learning and development used for spoken language understanding for the MiPad task; Tap & Talk multimodal interaction and user interface design; back channel communication and MiPad's error repair strategy; and finally, user study results that demonstrate the superior throughput achieved by the Tap & Talk multimodal interaction over the existing pen-only PDA interface. These user study results highlight the crucial role played by speech in enhancing the overall user experience in MiPad-like human-computer interaction devices.