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The design decisions for a distributed-mixed control structure for controlling a test rig currently being designed within the Gran Telescopio Canarias (GTC) project [gtcp] are described. We show the proposed control system structure and the simulations performed on a dynamical model of the test rig. The simulations show that the distributed-mixed control with a fast local loop reduces the system response...
Design-time analysis and verification of distributed real-time embedded systems necessitates the modeling of the time-varying performance of the network and comparing that to application requirements. Earlier work has shown how to build a system network model that abstracted away the network's physical medium and protocols which govern its access and multiplexing. In this work we show how to apply...
Crowdsourcing-based video service systems, e.g., Thunder Crystal, are novel content distribution platforms composed by a large number of agent devices, acting like miniservers. Most agents are normal Internet users who would like to earn rewarded cash by uploading content through their devices. Compared with CDN, the bandwidth cost is much cheaper; while compared with Peer-to-Peer(P2P), the bandwidth...
Efforts were made to integrate emerging Vehicular Ad-hoc Network (VANETs) with the mobile internet architecture through Road Side Unit (RSU) to enhance its operational capabilities for safety and non safety applications. Transmission Control Protocol (TCP) is one of the prominent protocol that contributes a considerable amount of internet traffic as the vast majority of internet applications such...
Smart grid paradigm is hailed as the Holy Grail to manage the future electricity consumption in a sustainable manner, and demand response (DR) is a fundamental component in the realization of smart grids. However, DR requires active household participation and in the previous studies monetary benefit is identified as the main motivation for the households to participate. In this paper, we analyze...
Next-generation digital broadcasting system transmits the DASH segment files. Delays and inefficient use of resources are the major challenges in the transmission of DASH segment files in broadcasting systems. Because the size of DASH segment files varies even though the files have the same quality, and broadcasting systems uses the fixed resource. Delay is an important problem in broadcasting systems...
Today's leadership computing facilities have enabled the execution of transformative simulations at unprecedented scales. However, analyzing the huge amount of output from these simulations remains a challenge. Most analyses of this output is performed in post-processing mode at the end of the simulation. The time to read the output for the analysis can be significantly high due to poor I/O bandwidth,...
Given the rapid change in processor architecture in the past years, there is a driving necessity to assess processor performance for a high performance computation workload. Assessing performance for a given workload is important to understand which architecture parameters the workload performance is sensitive to. A given workload can be categorized as memory bounded, compute bounded, or in between...
Software Defined Network (SDN) may significantly enhance network and service management by enabling separated control and data planes. The centralized OpenFlow controller with a global vision of network states offers a promising approach to realizing flow-based admission control for supporting Quality of Service (QoS) provisioning in SDN. However, per-flow process brings in challenges to scalability...
Fully Integrated Voltage Regulator (FIVR) has been introduced on Intel® Xeon® microprocessors which are switching power converters on die. The FIVR design includes air core inductor structures implemented on the package along with output capacitor, compensators, power transistors and control circuits implemented on-die. FIVR analysis has to comprehend and co-optimize both the package and the die....
Wireless communication has achieved great proliferation in communication technologies. IEEE 802.11 WLANs have been widely deployed as wireless access mechanism technology. To keep up with growing bandwidth and data rate requirements, legacy standards such as IEEE 802.11 have been deeply researched for their operation in multi-channel environment through usage of multiple interfaces. In the multi-channel...
Large multimedia files are accessed by a high number of mobile users over the Internet. Therefore, the bandwidth demand for mobile Internet access is increasing exponentially. To answer users' demand, carrier aggregation is proposed in LTE-A. In carrier aggregation, the best available one or more component carriers of each band are assigned as primary and secondary component carriers to each user...
In the present paper, the applicability of various on-ground antenna type at 2.45 GHz for launching creeping waves is examined. The performance of three antenna configurations is compared with the discone having purely dominant normal polarization to a body surface. The results are set against an analytical path loss model for a wireless body area network. The type of the studied antennas on a ground...
Connected vehicles are promoted with the use of different communication technologies for diverse applications. A host with multiple network devices is referred to as a multi-homed node. Stream Control Transmission Protocol (SCTP) is an IETF standard which supports multi-homing. However, original SCTP multi-homing functionality is only used when the primary address becomes unavailable. This paper presents...
P2P live streaming system is one of the most popular Internet applications which develop rapidly in the past decade. However, some common problems, such as long startup delay and unsmooth playback, seriously restrict user's experience on live streaming. In this paper, we propose a novel but simple scheme, namely guarantee mechanism of contingency resource (GMCR), which can improve the quality of service...
The worst-case network throughput is an important performance metric of interconnection networks and it is of particular concern to real-time systems. The existing model for throughput analysis assumes that the router nodes will not constrain the throughput, and hence the ideal throughput of the network is determined completely by congestion in the channels/links. In many recently proposed NoCs, however,...
A current-mode approach is often used when designing front-end electronics for Silicon Photomultipliers, to cope with the peculiar features of this kind of detectors. Very low input resistance Rin and bandwidth BW as large as possible are classic design choices for the preamplifier, since it is commonly assumed that timing accuracy performance are optimized if this strategy is adopted. In our study,...
Software, even if carefully optimized, rarely reaches the peak performance of a processor. Understanding which hardware resource is the bottleneck is difficult but important as it can help with both further optimizing the code or deciding which hardware component to upgrade for higher performance. If the bottleneck is the memory bandwidth, the roofline model provides a simple but instructive analysis...
VoD (Video-on-Demand) has become a hot topic over the last few years. Research was conducted on reducing the bandwidth cost of it. Different from conventional schemes like batching and patching, pushing popular videos to users with external storage during off-peak periods gives a new perspective. In this paper, we propose a new scheme under a hierarchical network environment, named “PPVoD (Pre-Pushing...
The dispersive transfer function has been derived in this paper to describe the distortions on pulse propagation in the ionosphere. As the crucial parameter in the function, the dispersive coefficient has been discussed and calculated on condition that the ionosphere is spherical stratified. Furthermore, simulation has been conducted to illustrate the low-pass filtering modulation and pulse mixing...
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