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We present simulations of blood and cancer cell separation in complex microfluidic channels with subcellular resolution, demonstrating unprecedented time to solution, performing at 65.5% of the available 39.4 PetaInstructions/s in the 18, 688 nodes of the Titan supercomputer. These simulations outperform by one to three orders of magnitude the current state of the art in terms of numbers of simulated...
Stream based data processing model is proven to be an established method to optimize data-intensive applications. Data-intensive applications involve movement of huge amount of data between execution nodes that incurs large costs. Data-streaming model improves the execution performance of such applications. In the stream-based data processing model, performance is usually measured by throughput and...
This paper investigates the performance of an overloaded multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system with a repetition code. It has been demonstrated that diversity with block coding prevents the performance degradation induced by signal multiplexing. However, the computational complexity of a joint decoding scheme increases exponentially with the...
This paper proposes a performance model for mobile networks carrying adaptive streaming traffic. The proposed model takes into account the flow dynamics in addition to the main parameters influencing the performance of adaptive streaming, such as the playout buffer and the video bit rates. We show how to compute several performance metrics like the average video bit rate, the deficit rate, defined...
We study TCP performance over ON-OFF channels, i.e., channels which are busy/unavailable for transmissions intermittently. The data may also be subject to random errors. Such situations arise in cognitive radio networks when secondary users opportunistically use the channel when the licensed user is not using it. We use a Markov model to evaluate the TCP throughput and probability of retransmission...
In this paper, we study a cooperative two-hop network with multiple sources and multiple relays where the energy required for the relays is transferred by the sources. In return, the relays transmit the sources' data, along with their own data, to the destination. We consider the setup where each node's objective is to maximize the amount of its own data delivered to the destination. We take a game...
This paper focuses on modelling and performance evaluation of an Intermodal Freight Transport Terminal (IFTT), the rail-road inland terminal of a leading Italian intermodal logistics company. The IFTT is regarded as a discrete event system and is modelled in a timed Petri net framework. By means of suitable performance indices, we simulate the Petri net model and evaluate the operational performance...
For two main problems of the existing stream processing model: lack of support for iterative computing and tight coupling, the paper proposes a real-time stream processing model based on directed graph with sources and sinks, which supports both general DAG computing by means of directed circle detection and iteration protection as well as iterative feedback stream computing of directed circles, tow-way...
The Network-on-chip (NoC) based multiprocessor system-on-chip (MPSoCs) is becoming a promising architecture to meet modern applications' ever-increasing demands for computing capability under limited power budget. NoC traffic patterns are essential tools for NoC performance assessment and architecture design exploration. In this paper, we present a systematic NoC traffic modeling and generation methodology...
High Throughput Computing (HTC) is a powerful paradigm allowing vast quantities of independent work to be performed simultaneously. However, until recently little evaluation has been performed on the energy impact of HTC. Many organisations now seek to minimise energy consumption across their IT infrastructure though it is unclear how this will affect the usability of HTC systems. We present here...
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...
Applications dealing with huge amounts of data suffer significant performance impacts when they are deployed on top of an hybrid platform (i.e. The extension of a local infrastructure with external cloud resources). More precisely, through a set of preliminary experiments we show that mechanisms which enable on demand extensions of current Distributed File Systems (DFSes) are required. These mechanisms...
The waiting time for patients in outpatient departments of university hospitals is a problem throughout the world. Outpatient departments face increasing pressure to improve the quality of their services through effective appointment scheduling in an effort to reduce waiting time. We analyzed the appointment scheduling system in the Obstetrics Gynecology Department at King Abdulaziz University Hospital,...
The design of wireless embedded systems needs their efficient and realistic simulation to verify that requirements are met. The reproduction of communication behavior is crucial to assess the performance of hardware and software components, e.g., dependability and energy consumption. This work presents and discusses different levels of abstraction for the simulation of the communication behavior....
Congestion control plays a significant role in maintaining sufficient network throughput. Variety of methods and algorithms are proposed to solve the bottleneck issue. This paper describes a method based on a particle swarm optimization algorithm and piecewise affine controller for non-stationary, discrete, dynamical model of data exchange network. This solution allows active network nodes buffer...
Typically, mobile users cluster around points of interest in dense urban environments such as city centers forming so-called data traffic hot spots and hot zones. To provide capacity to such users efficiently, mobile operators deploy small cells. However, the deployment of heterogeneous networks, which consist of overlaying macro cells and many co-channel small cells, entails many problems. One typical...
Self-organizing networks (SONs) can carry out their optimization procedures in an on- or off-line manner. On one hand, an online SON solution optimizes network parameters during operation. On the other hand, an offline SON solution employs a simulation environment of the network to be optimized in order to perform an offline parameter optimization before applying changes to the network. Thus far,...
The high performance Digital Signal Processors (DSPs) currently manufactured by Texas Instruments are heterogeneous multiprocessor architectures. Programming these architectures is a complex task often reserved to specialized engineers because the bottlenecks of both the algorithm and the architecture need to be deeply understood in order to obtain a fairly parallel execution. The PREESM framework...
The advent of cloud computing technology has made its presence effectively felt in various application areas such as business, industry, scientific, administrative, astronomy, high-energy physics, information, education etc. Its capability of meeting the various continuously changing demands in all fields makes it increasingly popular. In order to use cloud computing technology, the user has to make...
Improving Quality of Service (QoS) in wireless networks is important and necessary for mobile users. We have previously proposed Comfort Route (CR) Navigation, which navigates users to their destinations using high QoS communication areas, such as Wi-Fi APs, rather than the geographical Shortest Route (SR). In this paper, we employ an analytical model to estimate the CR gain in a theoretical manner...
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