Stergios Stergiou

Bio: Stergios Stergiou is an academic researcher from Fujitsu. The author has contributed to research in topics: Binary decision diagram & Set (abstract data type). The author has an hindex of 20, co-authored 118 publications receiving 1819 citations. Previous affiliations of Stergios Stergiou include Google & National and Kapodistrian University of Athens.

NoC synthesis flow for customized domain specific multiprocessor systems-on-chip

Abstract: The growing complexity of customizable single-chip multiprocessors is requiring communication resources that can only be provided by a highly-scalable communication infrastructure. This trend is exemplified by the growing number of network-on-chip (NoC) architectures that have been proposed recently for system-on-chip (SoC) integration. Developing NoC-based systems tailored to a particular application domain is crucial for achieving high-performance, energy-efficient customized solutions. The effectiveness of this approach largely depends on the availability of an ad hoc design methodology that, starting from a high-level application specification, derives an optimized NoC configuration with respect to different design objectives and instantiates the selected application specific on-chip micronetwork. Automatic execution of these design steps is highly desirable to increase SoC design productivity. This work illustrates a complete synthesis flow, called Netchip, for customized NoC architectures, that partitions the development work into major steps (topology mapping, selection, and generation) and provides proper tools for their automatic execution (SUNMAP, xpipescompiler). The entire flow leverages the flexibility of a fully reusable and scalable network components library called xpipes, consisting of highly-parameterizable network building blocks (network interface, switches, switch-to-switch links) that are design-time tunable and composable to achieve arbitrary topologies and customized domain-specific NoC architectures. Several experimental case studies are presented In the work, showing the powerful design space exploration capabilities of the proposed methodology and tools.

/spl times/pipes Lite: a synthesis oriented design library for networks on chips

Abstract: The limited scalability of current bus topologies for systems on chips (SoCs) dictates the adoption of networks on chips (NoCs) as a scalable interconnection scheme. Current SoCs are highly heterogeneous in nature, denoting homogeneous, preconfigured NoCs as inefficient drop-in alternatives. While highly parametric, fully synthesizeable (soft) NoC building blocks appear as a good match for heterogeneous MPSoC architectures, the impact of instantiation-time flexibility on performance, power and silicon cost has not yet been quantified. The paper details /spl times/pipes Lite, a design flow for automatic generation of heterogeneous NoCs. /spl times/pipes Lite is based on highly customizable, high frequency and low latency NoC modules, that are fully synthesizeable. Synthesis results provide modules that are directly comparable, if not better, than the current published state-of-the-art NoCs in terms of area, power latency and target operating frequency measurements.

Data aggregation platform

Abstract: In particular embodiments, a method includes accessing an original data stream from a sensor, associating a timestamp with each of the samples in the data stream based on a system clock, and recording the original data stream with the associated timestamps.

Modeling Topics Using Statistical Distributions

Abstract: In one embodiment, modeling topics includes accessing a corpus comprising documents that include words. Words of a document are selected as keywords of the document. The documents are clustered according to the keywords to yield clusters, where each cluster corresponds to a topic. A statistical distribution is generated for a cluster from words of the documents of the cluster. A topic is modeled using the statistical distribution generated for the cluster corresponding to the topic.

Determining Words Related To A Given Set Of Words

Abstract: In one embodiment, display of a user entry window of a graphical user interface is initiated. Search terms entered into the user entry window to initiate a first search are received. One or more first search results from a corpus of documents are determined according to the search terms. Display of the search terms at a current search terms window of the graphical user interface is initiated. Display of the first search results at a search results window of the graphical user interface is initiated. Display of the first search suggestions at a search suggestion window of the graphical user interface is initiated.

A survey of research and practices of Network-on-chip

Abstract: The scaling of microchip technologies has enabled large scale systems-on-chip (SoC). Network-on-chip (NoC) research addresses global communication in SoC, involving (i) a move from computation-centric to communication-centric design and (ii) the implementation of scalable communication structures. This survey presents a perspective on existing NoC research. We define the following abstractions: system, network adapter, network, and link to explain and structure the fundamental concepts. First, research relating to the actual network design is reviewed. Then system level design and modeling are discussed. We also evaluate performance analysis techniques. The research shows that NoC constitutes a unification of current trends of intrachip communication rather than an explicit new alternative.

Computer Architecture, Fifth Edition: A Quantitative Approach

Abstract: The computing world today is in the middle of a revolution: mobile clients and cloud computing have emerged as the dominant paradigms driving programming and hardware innovation today. The Fifth Edition of Computer Architecture focuses on this dramatic shift, exploring the ways in which software and technology in the "cloud" are accessed by cell phones, tablets, laptops, and other mobile computing devices. Each chapter includes two real-world examples, one mobile and one datacenter, to illustrate this revolutionary change. Updated to cover the mobile computing revolutionEmphasizes the two most important topics in architecture today: memory hierarchy and parallelism in all its forms.Develops common themes throughout each chapter: power, performance, cost, dependability, protection, programming models, and emerging trends ("What's Next")Includes three review appendices in the printed text. Additional reference appendices are available online.Includes updated Case Studies and completely new exercises.

Outstanding Research Problems in NoC Design: System, Microarchitecture, and Circuit Perspectives

Abstract: To alleviate the complex communication problems that arise as the number of on-chip components increases, network-on-chip (NoC) architectures have been recently proposed to replace global interconnects. In this paper, we first provide a general description of NoC architectures and applications. Then, we enumerate several related research problems organized under five main categories: Application characterization, communication paradigm, communication infrastructure, analysis, and solution evaluation. Motivation, problem description, proposed approaches, and open issues are discussed for each problem from system, microarchitecture, and circuit perspectives. Finally, we address the interactions among these research problems and put the NoC design process into perspective.

System and method for server based control

Abstract: A system and method in a building or vehicle for an actuator operation in response to a sensor according to a control logic, the system comprising a router or a gateway communicating with a device associated with the sensor and a device associated with the actuator over in-building or in-vehicle networks, and an external Internet-connected control server associated with the control logic implementing a PID closed linear control loop and communicating with the router over external network for controlling the in-building or in-vehicle phenomenon. The sensor may be a microphone or a camera, and the system may include voice or image processing as part of the control logic. A redundancy is used by using multiple sensors or actuators, or by using multiple data paths over the building or vehicle internal or external communication. The networks may be wired or wireless, and may be BAN, PAN, LAN, WAN, or home networks.