Evolutionary strategy based improved motion estimation technique for H.264 video coding

In this paper we propose an improved motion estimation algorithm based on evolutionary strategy (ES) for H.264 video codec applied to video. The proposed technique works in a parallel local search for macroblocks. For this purpose (mu+lambda) ES is used with an initial population of heuristically and randomly generated motion vectors. Experimental results show that the proposed scheme can reduce the computational complexity up to 50% of the motion estimation algorithm used in the H.264 reference codec at the same picture quality. Therefore, the proposed algorithm provides a significant improvement in motion estimation in the H.264 video codec

Rejecting spam during SMTP sessions

This paper analyzes a spam rejection scheme at Simple Mail Transfer Protocol (SMTP) sessions. This scheme utilizes a layer-3 e-mail pre-classification technique to estimate e-mail classes before an SMTP session ends. We study the spam rejection scheme using discrete-time Markov chain analysis and analyze the performance of the proposed scheme under different e-mail traffic loads and service capacities. The proposed scheme reduces the e-mail volume to be queued and processed by e-mail servers. This reduces non-spam e-mail queuing delay and loss, and protects e-mail servers from being overloaded by spam traffic

Mobile-IP ad-hoc network MPLS-based with QoS support.

The support for Quality of Service (QoS) is the main focus of this thesis. Major issues and challenges for Mobile-IP Ad-Hoc Networks (MANETs) to support QoS in a multi-layer manner are considered discussed and investigated through simulation setups. Different parameters contributing to the subjective measures of QoS have been considered and consequently, appropriate testbeds were formed to measure these parameters and compare them to other schemes to check for superiority. These parameters are: Maximum Round-Trip Delay (MRTD), Minimum Bandwidth Guaranteed (MBG), Bit Error Rate (BER), Packet Loss Ratio (PER), End-To-End Delay (ETED), and Packet Drop Ratio (PDR) to name a few. For network simulations, NS-II (Network Simulator Version II) and OPNET simulation software systems were used.Dept. of Electrical and Computer Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .A355. Source: Masters Abstracts International, Volume: 44-03, page: 1444. Thesis (M.Sc.)--University of Windsor (Canada), 2005

A Very Low Complexity Successive Symbol-by-Symbol Sequence Estimator for Faster-Than-Nyquist Signaling

In this paper, we investigate the sequence estimation problem of binary and quadrature phase shift keying faster-than-Nyquist (FTN) signaling and propose two novel low-complexity sequence estimation techniques based on concepts of successive interference cancellation. To the best of our knowledge, this is the first approach in the literature to detect FTN signaling on a symbol-by-symbol basis. In particular, based on the structure of the self-interference inherited in FTN signaling, we first find the operating region boundary---defined by the root-raised cosine (rRC) pulse shape, its roll-off factor, and the time acceleration parameter of the FTN signaling---where perfect estimation of the transmit data symbols on a symbol-by-symbol basis is guaranteed, assuming noise-free transmission. For noisy transmission, we then propose a novel low-complexity technique that works within the operating region and is capable of estimating the transmit data symbols on a symbol-by-symbol basis. To reduce the error propagation of the proposed successive symbol-by-symbol sequence estimator (SSSSE), we propose a successive symbol-by-symbol with go-back-$K$ sequence estimator (SSSgb$K$SE) that goes back to re-estimate up to $K$ symbols, and subsequently improves the estimation accuracy of the current data symbol. Simulation results show that the proposed sequence estimation techniques perform well for low intersymbol interference (ISI) scenarios and can significantly increase the data rate and spectral efficiency. Additionally, results reveal that choosing the value of $K$ as low as $2$ or $3$ data symbols is sufficient to significantly improve the bit-error-rate performance. Results also show that the performance of the proposed SSSgb$K$SE, with $K = 1$ or $2$, surpasses the performance of the lowest complexity equalizers reported in the literature, with reduced computational complexity.Comment: IEEE Access, accepte

A Stateful Approach to Generate Synthetic Events from Kernel Traces

We propose a generic synthetic event generator from kernel trace events. The proposed method makes use of patterns of system states and environment-independent semantic events rather than platform-specific raw events. This method can be applied to different kernel and user level trace formats. We use a state model to store intermediate states and events. This stateful method supports partial trace abstraction and enables users to seek and navigate through the trace events and to abstract out the desired part. Since it uses the current and previous values of the system states and has more knowledge of the underlying system execution, it can generate a wide range of synthetic events. One of the obvious applications of this method is the identification of system faults and problems that will appear later in this paper. We will discuss the architecture of the method, its implementation, and the performance results

How Can Personality Influence Perception on Security of Context-Aware Applications?

[Context and Motivation] Our lives are being transformed by context-aware software applications with important social, environmental, and economic implications. [Question/Problem] Experts recognized that quality attributes, e.g. security, are the cornerstone to get healthy social implications of these applications. However, do end-users (service consumers) perceive these attributes as so important? [Methodology] To answer this question, we designed a survey, to understand how end-users perceive security of context-aware software applications and how the users’ personality traits might influence their perceptions. To this end, we did a web-based survey that embeds two animated-demonstration videos in order to present i) the functionality of a context-aware mobile app, and ii) some vulnerabilities of the mobile app. It involved 48 subjects divided in two groups: subjects with software engineering (SE) background (Group A) and subjects without any SE background (Group B). [Results] Our study found that the importance of confidentiality and integrity is more clearly perceived by subjects with SE backgrounds (Group A). Accountability is more difficult to be perceived by subjects. And this difficulty can be even more pronounced for subjects without any SE background (Group B). Our findings suggest that importance preferences on security are influenced by personality types. For instance, open-minded people have a higher propensity to perceive the importance of confidentiality and integrity. Whilst, people with a high level of agreeableness hold quite different perceptions regarding the importance of authenticity and accountability. Analyzing the level of association between personality and the perceived importance on security, we found that the importance perceptions on confidentiality are influenced by the personality of subjects from Group B. And, the changes (positive an negative) in the importance perception on confidentiality are very strongly influenced by personality, even more so by the personality of subjects from Group B.</p