Sustainable management of crustacean populations requires an understanding of the range of factors affecting different crustacean species. Recently, a high prevalence of a paramyxid parasite, ...Paramarteilia canceri, was reported in velvet crabs Necora puber in Ireland. Similar parasites have been known to cause mass mortalities in bivalves and, as velvet crabs are an important commercial species, these parasite infections are cause for concern. The main objective of this study was to examine variation in P. canceri infections in relation to host biology and season over a 2 yr period. In addition, we tested a range of host tissues and organs to gain more information on the host-parasite interaction. The parasite was present in all tissues and organs investigated, including the gonad and eggs of a berried female. Parasite prevalence was highest in the cuticular epithelium and hepatopancreas. Both annual and seasonal variation was found in parasite prevalence and parasite load. No difference was found in parasite prevalence or parasite load with either crab size or crab sex. Granulomas as a response to infection were significantly more abundant in infected velvet crab individuals. The results of this study provide important information on the host-parasite interaction between P. canceri and the velvet crab and highlight the importance of including parasite monitoring in the management of crustacean fisheries.
This article presents IDEA1, a SystemC-based system-level design and simulation framework for WSNs. It allows the performance evaluation (e.g., packet delivery rate, transmission latency and energy ...consumption) at high level, but with elaborate models of the hardware and software of sensor nodes. Many hardware components are modeled and the IEEE 802.15.4 standard is implemented. IDEA1 uses a clock-based synchronization mechanism to support simulations with cycle accurate communication and approximate time computation. The simulation results have been validated by a testbed of 9 nodes. The average deviation between the IDEA1 simulations and experimental measurements is 4.6%. The performances of IDEA1 have also been compared with NS-2. To provide a similar result (deviation less than 5%) at the same abstraction level, the simulation of IDEA1 is 2 times faster than NS-2. Moreover, with the hardware and software co-simulation feature, IDEA1 provides more detailed modeling of sensor nodes. Finally, IDEA1 is used to study a real-time industrial application in which a wireless sensor and actuator network is deployed on a vehicle to measure and control vibrations. By the simulation, some preliminary designs based on IEEE 802.15.4 protocols and two different hardware platforms are evaluated.
This book discusses the opportunities offered by disruptive technologies to overcome the economical and physical limits currently faced by the electronics industry. It provides a new methodology for ...the fast evaluation of an emerging technology from an architectural prospective and discusses the implications from simple circuits to complex architectures. Several technologies are discussed, ranging from 3-D integration of devices (Phase Change Memories, Monolithic 3-D, Vertical NanoWires-based transistors) to dense 2-D arrangements (Double-Gate Carbon Nanotubes, Sublithographic Nanowires, Lithographic Crossbar arrangements). Novel architectural organizations, as well as the associated tools, are presented in order to explore this freshly opened design space.
On-chip integrated lasers are key devices to deliver the high bandwidth expected from nanophotonic interconnects. However, lasers are highly sensitive to temperature variation, which influences the ...lasing efficiency and the wavelengths of emitted optical signals, both of which are key factors in interconnect power efficiency. It is, thus, necessary to develop techniques for efficient thermal-aware control of lasers. In this brief, we propose the grouping of lasers for efficient power control of their temperature. Laser grouping is carried out taking into account the layout symmetries, and a design method allows the definition of control laws.
Despite considerable debate in the literature, social work continues to invest considerable analytical and empirical energy on understanding, recognizing and critiquing the nature and form of its ...knowledge base. Although such contributions have advanced the discussion, what is largely absent but essential to this debate is an understanding of how practitioners actually express what they know. This paper focuses specifically on this issue and in so doing, advances one template for working with practice language. From a qualitative, multi-method research methodology, it was found that participants' communication of their knowledge was not always formal and labelled. Knowing could be expressed via examples, stories, metaphor, as well as understandings that resembled existing theoretical knowledge or that which had been reformulated and synthesized in practice. The paper emphasizes the necessity to recognize this diversity in knowledge communication, so as to accurately and responsibly map actual practice knowledge, but in doing so, also raises the issue of addressing limitations that such recognition brings. The issue of competent and clear practice articulation is a topic to which the profession should give serious attention. The inability of practitioners to explicitly articulate the basis of practice behaviour places them at a considerable disadvantage in a competitive labour market.
Design technology to address the new and vast problem of heterogeneous embedded systems design while remaining compatible with standard "More Moore flows, i.e. capable of simultaneously handling ...both silicon complexity and system complexity, represents one of the most important challenges facing the semiconductor industry today and will be for several years to come. While the micro-electronics industry, over the years and with its spectacular and unique evolution, has built its own specific design methods to focus mainly on the management of complexity through the establishment of abstraction levels, the emergence of device heterogeneity requires new approaches enabling the satisfactory design of physically heterogeneous embedded systems for the widespread deployment of such systems. Heterogeneous Embedded Systems, compiled largely from a set of contributions from participants of past editions of the Winter School on Heterogeneous Embedded Systems Design Technology (FETCH), proposes a necessarily broad and holistic overview of design techniques used to tackle the various facets of heterogeneity in terms of technology and opportunities at the physical level, signal representations and different abstraction levels, architectures and components based on hardware and software, in all the main phases of design (modeling, validation with multiple models of computation, synthesis and optimization). It concentrates on the specific issues at the interfaces, and is divided into two main parts. The first part examines mainly theoretical issues and focuses on the modeling, validation and design techniques themselves. The second part illustrates the use of these methods in various design contexts at the forefront of new technology and architectural developments.
The many cores design research community have shown high interest in optical crossbars on chip for more than a decade. Key properties of optical crossbars, namely a) contention-free data routing b) ...low-latency communication and c) potential for high bandwidth through the use of WDM, motivate several implementations. These implementations demonstrate very different scalability and power efficiency ability depending on three key design factors: a) the network topology, b) the considered layout and c) the insertion losses induced by the fabrication process. The emerging design technique relying on multi-layer deposited silicon allows reducing optical losses, which may lead to significant reduction of the power consumption. In this paper, multi-layer deposited silicon based crossbars are proposed and compared. The results indicate that the proposed ring-based network exhibits, on average, 22% and 51.4% improvement for worst-case and average losses respectively compared to the most power-efficient related crossbars.
The many cores design research community have shown high interest in optical crossbars on chip for more than a decade. Key properties of optical crossbars, namely a) contention free data routing b) ...low latency communication and c) potential for high bandwidth through the use of WDM, motivate several implementations of this type of interconnect. These implementations demonstrate very different scalability and power efficiency ability depending on three key design factors: a) the network topology, b) the considered layout and the c) the injection losses induced by the fabrication process. In this paper, the worst-case optical losses of crossbar implementations are compared according to the factors mentioned above. The comparison results has the potential to help many cores system designer to select the most appropriate crossbar implementation according, for instance, to the number of IP cores and the chip die size.
Optical technology promises to solve the bottleneck communication in Multiprocessor Systems-on-Chip (MPSoCs) by integrating high speed interconnections. From the system point of view, one of the most ...critical problems in optical communication is channel bandwidth, strongly influencing the system performance and cost. Channel bandwidth establishes the number of waveguides and wavelengths to serve each communication request. Dynamic approaches allow to define the channel bandwidth at the runtime, which leads flexible systems but may turn their performance unpredictable. Design-time approaches appear as an attractive alternative to define the channel bandwidth for systems that require performance guarantees and simple solutions. A method for exploring the channel bandwidth design space is thus mandatory in order to identify the best communication channel size. In this work we explore the trade-off among channel bandwidth alternatives, performance, area and power. We show that the channel size has a strong impact on the system performance and cost. We employ synthetic and real application traffic which has been executed on Gem5. As a result we show that different channel bandwidth can improve the execution time of an application up to 75% while including low area and power penalties.
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