Evaluation of contrast agent dose and diffusion coefficient measurement on vessel size index estimation

Magnetic Resonance Materials in Physics, Biology and Medicine - The goal of this study is to examine the effect of contrast agent (CA) dose and diffusion coefficient on the estimation of vessel...     

Galerkin’s approach for buckling analysis of functionally graded anisotropic nanoplates/different boundary conditions

Engineering with Computers - For the first time, buckling behavior of functionally graded (FG) nanoplates made of anisotropic material (beryllium crystal as a hexagonal material) is investigated....     

An Accurate Persian Part-of-Speech Tagger

The processing of any natural language requires that the grammatical properties of every word in that language are tagged by a part of speech (POS) tagger.To present a more accurate POS tagger for the Persian language, we propose an improved and accurate tagger called IAoM that supports properties of text tospeech systems such as Lexical Stress Search, Homograph words Disambiguation, Break Phrase Detection, and main aspects of Persian morphology. IAoMuses Maximum Likelihood Estimation (MLE) to determine the tags of unknown words. In addition, it uses a few defined rules for the sake of achieving highaccuracy. For tagging the input corpus, IAoM uses a Hidden Markov Model (HMM) alongside the Viterbi algorithm. To present a fair evaluation, we haveperformed various experiments on both homogeneous and heterogeneous Persian corpora and studied the effect of the size of training set on the accuracyof IAoM. Experimental results demonstrate the merit of the proposed tagger in achieving an overall accuracy of 97.6%.     

Service discovery in the Internet of Things: review of current trends and research challenges

Wireless Networks - Recent technologies have made the life of people more comfortable and more straightforward than it was before. With the development of information technology, the Internet of...     

Effect of waste EVA (Ethylene Vinyl Acetate) and Waste CR(Crumb Rubber) on characteristics of Bitumen

In this research, waste Polymer Ethylene Vinyl Acetate (EVA) in three levels 3, 5 and 7 percent and waste crumb rubber in three levels 2, 4 and 6 percent were used as modifier of 85/100 refinery bitumen of Iran. In order to evaluate low temperature behavior of modified bitumen and it's compare with low temperature behavior of base bitumen, Superpave protocol has been used in this way that Bending Beam Rheometer test (BBR) has been done and with measuring creep stiffness indexes and creep rate, low temperature behavior of bitumen has been accounted according to SHRP standard. With doing Bending Beam Rheometer test (BBR), it is realized that these additive caused to improvement features of bitumen low temperature prior to base bitumen. In this way that 3% polymer Ethylene Vinyl Acetate (EVA) and 4% waste crumb rubber are chosen as the optimum mixture. Then with doing Elastic Recovery test, rate of Elastic Recovery of modified bitumen is recognized including different percent of additives and with doing Rotary Viscometer test, viscosity (Pa.s) has been measured for examining pumping ability of modified bitumen.     

Structural response of vertically irregular tall moment‐resisting steel frames under pre‐ and post‐earthquake fire

Post‐earthquake fires (PEF) may result in a catastrophe in urban regions even worse than the earthquake itself. Most urban structures are not designed to resist two subsequent extreme loads such as earthquake and fire. Thus, these types of structures are too weak when subjected to the PEF loads. On the other hand, it is well understood that irregular building structures are more susceptible to sustain earthquake damage than regular buildings. Investigating irregular buildings can therefore be more important when there is a high possibility of PEF. While there are various irregularities, here, vertical irregularity is considered. The study is performed on one irregular seven‐story tall moment‐resisting steel frame designed based on the American Society of Civil Engineers code. The frame is firstly subjected to an earthquake load with the peak ground acceleration of 0.35 g and then is exposed to a generalized exponential fire curve. To make a comparison between the results, the PEF analysis is also performed for the regular frame. The results show that there is a marked difference between the PEF of the regular frame with that of the irregular frame. In addition, two types of failure—local and global—were observed during the analysis, where the local collapse is related to the deflection of beams, and the global collapse is pertained to the considerable movement of the columns. It is observed during the analysis that the irregular frames are more susceptible to collapse globally. Copyright © 2015 John Wiley & Sons, Ltd.     

Stochastic Design of Flood Control Systems; Uncertainty Propagation and Results Representation

Water Resources Management - The design and operation of flood control systems are always subjected to different uncertainties. In general, uncertainty occurs due to the inherent randomness of...     

Kinetic modeling of photoassisted-electrochemical process for degradation of an azo dye using boron-doped diamond anode and cathode with carbon nanotubes

To well describe the photoassisted-electrochemical process for treatment of the contaminated water, a new kinetic model was established based on the intrinsic reactions of the process. The kinetic model correlated apparent kinetic constants to operational parameters including applied current, initial dye concentration and flow rate. Degradation experiments were carried out with boron-doped diamond (BDD) anode and carbon nanotubes–polytetrafluoroethylene (CNTs–PTFE) cathode. The proposed kinetic model was validated by the experiments of C.I. Acid Blue 92 degradation in aqueous solution. The goodness of fitting (R² = 0.96) demonstrated that the new model could describe both the kinetics and the hydrodynamics of the photo-electrochemical system.     

Diversity achieving full-duplex DF relaying with joint relay-antenna selection under Nakagami-m fading environment

One of the main imperfections degrading the performance of full-duplex (FD) relaying systems is the outage floor. In this work, a power scaling method is proposed, which overcomes this effect even when there does not exist a direct channel between source and destination nodes. The system is composed of $K$ decode-and-forward (DF) FD relays over the Nakagami-m fading environment. To promote system performance, joint antenna and relay selection methods are employed in the FD relaying systems. Each FD relay is equipped with multiple antennas for receiving and the other for transmitting the information. The transmitting and receiving antennas are chosen based on the instantaneous channel variations, and one relay is selected to improve the signal-to-interference and noise ratio (SINR) of the FD relaying system. The performance of the proposed design is investigated. Moreover, the closed-form equations of the ergodic capacity and outage probability are attained. The analytical results are confirmed by different simulations. Results indicate that the proposed design achieves an additional spatial diversity gain because of using the antenna selection at the relay nodes. Moreover, by power scaling (PS) method, the system performance is effectively improved compared to the conventional FD relaying structures.