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Cankaya, Turkey

Haidar Sharif M.,Gediz University | Djeraba C.,Lille University of Science and Technology
Pattern Recognition | Year: 2012

Detection of aberration in video surveillance is an important task for public safety. This paper puts forward a simple but effective framework to detect aberrations in video streams using Entropy, which is estimated on the statistical treatments of the spatiotemporal information of a set of interest points within a region of interest by measuring their degree of randomness of both directions and displacements. Entropy is a measure of the disorder/randomness in video frame. It has been showed that degree of randomness of the directions (circular variance) changes markedly in abnormal state of affairs and does change only direction variation but does not change with displacement variation of the interest point. Degree of randomness of the displacements has been put in for to counterbalance this deficiency. Simple simulations have been exercised to see the characteristics of these crude elements of entropy. Normalized entropy measure provides the knowledge of the state of anomalousness. Experiments have been conducted on various real world video datasets. Both simulation and experimental results report that entropy measures of the frames over time is an outstanding way to characterize anomalies in videos. © 2012 Elsevier Ltd. All rights reserved. Source


Objective: The aim of this study was to examine the prevalence of illicit substance use, alcohol consumption, and psychosocial distress among Norwegian patients on waiting lists for substance use disorder treatment. Methods: Patients on waiting lists at 16 Norwegian treatment clinics for substance use disorders received a mailed questionnaire or were recruited during pre-treatment meetings (response rate 40%, n = 203). The patients completed a questionnaire consisting of validated screening tools of substance use and psychosocial distress. When available, Norwegian norm data were used as a reference group in analyses. Results: Among patients who reported use of illicit substances in the last month, 40% reported scores above cut-off. About 50% of those who had consumed alcohol reported a severe pattern of alcohol consumption. A total of 60% of the sample reported severe symptom loads and nearly 70% of the sample reported interpersonal problems above cut-off. Compared to the norm data, patients on waiting lists reported more psychosocial distress on all the symptom dimensions, as expected. Conclusions: Patients on waiting lists reported substantial substance use and psychosocial burden. Pre-treatment interventions should be conducted among these patients. Treatment could benefit from more standardized screening routines and clinical assessments before patients enter treatment. The findings may challenge the Norwegian policy of supply-driven treatment services. © 2013 Copyright Taylor and Francis Group, LLC. Source


Kusetogullari H.,Gediz University
IEEE Journal on Selected Topics in Signal Processing | Year: 2015

In this paper, dynamic multiple description wavelet based image coding using enhanced particle swarm optimization (EPSO) is proposed for effective multimedia transmission in the dynamically changing network topologies such as mobile ad-hoc networks (MANETs). In wireless networks, multimedia transmission has become a challenging problem because of changing conditions over time such as packet loss rate (PLR), capacity/bandwidth, network and link conditions. The proposed method is used to simultaneously create optimal multiple description coding (MDC) or sub-images based on the dynamically changing capacity/bandwidth of wireless joint/disjoint communication channels/paths. To perform it, PSO is enhanced by adding a position mutation scheme as a generation feature to employ the proposed dynamic cost function to find the optimal solution within in a search space. To create MDs efficiently, three different wavelet transformation methods which are Discrete Wavelet Transform (DWT), Dual Tree-Complex Wavelet Transform (DT-CWT), and Stationary Wavelet Transform (SWT) are investigated. In this manner, a wavelet transform method is first applied to the given input image to create the sub-bands or set of coefficients as a search space, and then EPSO is employed to find optimal results in the search space to generate MDs. The proposed approach produces good quality of descriptions for effective multimedia transmission over dynamically changing and unreliable communication networks, particularly in wireless and ad-hoc networks (MANETs). The results of the proposed method are compared with the state-of-the-art techniques and simulation results demonstrate that using EPSO with DT-CWT provides a significant improvement of optimal and balanced MDC generation with good quality at different bit-rates. © 2014 IEEE. Source


Gungor A.,Gediz University | Erbay Z.,Ege University | Hepbasli A.,Ege University
Applied Energy | Year: 2011

In this study, three medicinal and aromatic plants (Foeniculum vulgare, Malva sylvestris L. and Thymus vulgaris) were dried in a pilot scale gas engine driven heat pump drier, which was designed, constructed and installed in Ege University, Izmir, Turkey. Drying experiments were performed at an air temperature of 45 °C with an air velocity of 1. m/s. In this work, the performance of the drier along with its main components is evaluated using exergy analysis method. The most important component for improving the system efficiency is found to be the gas engine, followed by the exhaust air heat exchanger for the drying system. An exergy loss and flow diagram (the so-called Grassmann diagram) of the whole drying system is also presented to give quantitative information regarding the proportion of the exergy input dissipated in the various system components, while the sustainability index values for the system components are calculated to indicate how sustainability is affected by changing the exergy efficiency of a process. Gas engine, expansion valve and drying ducts account for more than 60% amount of exergy in the system. The exergetic efficiency values are in the range of 77.68-79.21% for the heat pump unit, 39.26-43.24% for the gas engine driven heat pump unit, 81.29-81.56% for the drying chamber and 48.24-51.28% for the overall drying system. © 2010 Elsevier Ltd. Source


Sharif M.H.,Gediz University
Journal of Circuits, Systems and Computers | Year: 2014

Nowadays high-performance computing (HPC) architectures are designed to resolve assorted sophisticated scientific as well as engineering problems across an ever intensifying number of HPC and professional workloads. Application and computation of key trigonometric functions sine and cosine are in all spheres of our daily life, yet fairly time consuming task in high-performance numerical simulations. In this paper, we have delivered a detailed deliberation of how the micro-architecture of single-core Itanium® and Alpha 21264/21364 processors as well as the manual optimization techniques improve the computing performance of several mathematical functions. On describing the detailed algorithm and its execution pattern on the processor, we have confirmed that the processor micro-architecture side by side manual optimization techniques ameliorate computing performance significantly as compared to not only the standard math library's built-in functions with compiler optimizing options but also Intel® Itanium® library's highly optimized mathematical functions. © 2014 World Scientific Publishing Company. Source

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