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"Variable Structure Load Frequency Controller: Optimal Design and Chattering Reduction using Particle Swarm Optimization Algorithm"
No full textTwo Analytical Models for Evaluating Performance of Gigabit Ethernet Hosts with Finite Buffer
Get PDFTwo analytical models are developed to study the impact of interrupt overhead on operating system performance of network hosts with limited-size or finite buffer. Under heavy network traffic such as that of Gigabit Ethernet, the system performance will be negatively affected due to interrupt overhead caused by incoming traffic. In particular, packet loss, excessive latency and significant degradation in system throughput can be experienced. Also, user applications may livelock as the CPU power is mostly consumed by interrupt handling and protocol processing. In this paper, we present and compare two analytical models that capture host behavior and evaluate its performance. The first model is based on Markov processes and queueing theory, while the second, which is more accurate but more complex, is a pure Markov process. The models yield equations for a number of important system performance metrics. These performance metrics include throughput, latency, packet loss, stability condition, CPU utilizations of interrupt handling and protocol processing, and CPU availability for user applications. Both models yield closed-form solutions and equations that are either mathematically equivalent or very closely matching. Our analysis yields insight into understanding and predicting the impact of system and network choices on the performance of interrupt-driven systems when subjected to light and heavy network loads. More importantly, our analytical work can also be valuable in improving host performance. The paper gives guidelines and recommendations to address design and implementation issues. Simulation and reported experimental results show that our analytical models are valid and give a good approximation
Efficient Sample Rate Conversion for Software Radio Systems
No full textAn efficient sample rate conversion (SRC) method for software radio (SWR) systems is proposed. The proposed method modifies conventional single- or multistage SRC processes such that the computation of the output of a particular stage is performed in a hierarchical fashion. This SRC method consumes fewer computations than traditional SRC methods over a range of SRC factors and is especially suitable for SWR base station transmitters. The computational requirements of the proposed SRC method and conventional SRC methods are compared and simulation results of the proposed method are discussed
Scalable VLSI Design for Fast GF(p) Montgomery Inverse Computation
Get PDFThis paper accelerates a scalable GF(p) Montgomery inversion hardware. The hardware is made of two parts a memory and a computing unit. We modified the original memory unit to include parallel shifting of all bits which was a task handled by the computing unit. The new hardware modeling, simulating, and synthesizing is performed through VHDL for several 160-bits designs showing interesting speedup to the inverse computation
Treatment of simulated petrochemical wastewater by means of continuous electrocoagulation-ultrafiltration process
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An empirical study of relationships among extreme programming engineering activities
Get PDFExtreme programming (XP) is an agile software process that promotes early and quick production of working code. In this paper, we investigated the relationship among three XP engineering activities: new design, refactoring, and error fix. We found that the more the new design performed to the system the less refactoring and error fix were performed. However, the refactoring and error fix efforts did not seem to be related. We also found that the error fix effort is related to number of days spent on each story, while new design is not. The relationship between the refactoring effort and number of days spent on each story was not conclusive
A Fingerprinting System for Musical Content
Get PDFDriven by the recent advances in digital entertainment technologies, digital multimedia content (such as music and movies) is becoming a major part of the average computer user experience. Through daily interaction with digital multimedia content, large digital collections of music, audio and sound effects have emerged. Furthermore, these collections are produced/consumed by different groups of users such as the entertainment, music, movie and animation industries. Therefore, the need for identification and management of such content grows proportionally to the increasing widespread availability of such media virtually ”any time and any where” over the Internet. In this paper, we propose a novel algorithm for robust perceptual hashing of musical content using balanced multiwavelets (BMW). The procedure for generating robust perceptual hash values (or fingerprints) is described in details. The generated hash values are used for identifying, searching, and retrieving musical content from large musical databases. Furthermore, we illustrate, through extensive computer simulation, the robustness of the proposed framework to efficiently represent audio content and withstand several signal processing attacks and manipulations