Ali Hoseiny

A time-domain equalizer (TEQ) is proposed for MIMO-OFDM transmission in underwater acoustic (UWA) channels that simultaneously exhibit large delay and doppler spreads. The aim of the equalizer is to jointly mitigate the intercarrier interference (ICI) and interblock interference (IBI). In this paper, the well known basis expansion model (BEM) is used to describe the UWA channel. Then, the equalizer is derived based on maximizing the signal-to-interference-plus-noise-ratio (SINR). The performance of the proposed approach is demonstrated by numerical simulations. Also, a previously proposed frequency-domain equalizer (FEQ) for communication over doubly selective radio channels is applied to UWA channel and its performance is compared to that of the proposed TEQ.

In this research, adults of Tribolium castaneum (Herbst) and Rhyzopertha dominica (Fabricius) were exposed to various air pressures solely (first phase) and air pressures together with acrolein (second phase) in various durations and mortality rates were determined. Complete mortality of T. castaneum was obtained at 1, 3 and 6 h after exposure to 10, 30 and 50 mmHg, respectively. R. dominica showed 96.25% and 60% mortality during 3 and 10 h exposed to 10 and 30 mmHg, respectively. Percentage mortality of the insects in second phase was significantly higher than the rate in first phase. T. castaneum was more susceptible than R. dominica in the both phases.

The paper deals with experimental investigations on reinforcing the adhesive in single lap joints subjected to mechanical loads such as tensile, bending, impact and fatigue. The adhesive used for bonding was an epoxy reinforced with unidirectional and chopped glass fibres as well as micro-glass powder. The adherends were glass reinforced composite laminates. The bonding surfaces were prepared before joining. In the case of unidirectional fibres in the adhesive region, the fibre orientations considered were 0°, 45° and 90°. The volume fraction of fibres in the adhesive layer in all the cases was 30%. The volume fractions of micro-glass powder were 20%, 30% and 40%. The tensile, bending, impact and fatigue tests on the prepared specimens were conducted according to ASTM standards. The results show that except the 90° unidirectional orientation, reinforcing the adhesive with glass fibres or powder increases the joint strength. The use of volume fraction of 30% of micro-glass powder gave the best performance in the above loading conditions. The fatigue life increased by 125%, the ultimate joint strength in tension increased by 72%, the bending ultimate joint strength increased by 112% and the impact joint strength increased by 63%. The microstructure of the debonded area was examined and three modes of failure could be observed namely cohesive failure, light fibre-tear failure and thin layer cohesive failure.

The aim of this article is to propose an intelligent electrocardiogram classifier. The classifier is similar to probabilistic neural networks. In these networks, a user needs to set some parameters optionally. Improper selections may decrease the performance drastically. The proposed method needs no optional parameter settings and all required parameters are extracted from the statistics of the input signals. The proposed classifier has two layers and a database of known signals that has been categorized and labeled to M classes based on their similarities. The first layer calculates the similarities of the input unknown signal to the known signals of each class using Basis Radial functions and outputs Bayesian variables equal to the number of classes. The second layer is just a maximum selector of these Bayesian variables as the winner. In fact, it indicates that the input signal most probably belongs to the class in which Bayesian variable is maximum. Five classes of ECG signals from MIT-BIH arrhythmia database are selected to illustrate the good performance of the non-invasive proposed classifier compared to the previous methods. Moreover, acceptable low computational complexity and robustness against high noise are significant features of the proposed classifier.

A simple and efficient procedure for the synthesis of 2-arylquinazolin-4(3H)-ones has been developed through cyclocondensation of 2-aminobenzamide with aromatic aldehydes using tetrabutylammonium bromide (TBAB) as novel neutral ionic liquid catalyst in the presence of copper (II) chloride (CuCl2) as oxidizing agent under solvent-free conditions at 100 °C. In the absence of CuCl2 and under a nitrogen atmosphere, the unoxidized intermediates, 2-aryl-2,3-dihydroquinazolin-4(1H)-ones, were isolated. Treatment of these intermediates with CuCl2 in TBAB media gave the oxidized products 2-arylquinazolin-4(3H)-ones. On the other hand, cyclocondensation of 2-aminobenzamide with aromatic aldehydes in TBAB under microwave irradiation directly gave 2-arylquinazolin-4(3H)-ones.

To assess bone regeneration in critical sized defects in the rabbit calvarium, filled with the bone substitute calcium phosphate cement. Circular bone defects (8mm) were made in both parietal bones of 10 rabbits. One of the defects was filled with the calcium phosphate cement, and the other received autogenous bone harvested from the calvaria. The animals were killed at 3 or 6 weeks (n=5). Data analysis included qualitative assessment of the calvarial specimens and histomorphometric analysis was used to quantify the amount of new bone within the defects. The microscopic analysis of the samples showed bone healing with both calcium phosphate cement and autogenous bone graft. Data obtained from the histomorphometric analysis were statistically analyzed using 2-way analysis of variance and the Tukey's test. Data analysis showed that the autogenous bone graft had significantly more new bone compared with calcium phosphate cement at 3 and 6 weeks. Calcium phosphate cement at 6 weeks presented similar results to autogenous bone at 3 weeks. Both treatments presented an increase in bone healing with time. Treatments allowed bone regeneration that increased with time, however surgical cavities treated with the autogenous graft had more bone formation than those with calcium phosphate cement.

Tehran is one of the megacities of the world with a population of over eight million. Its air is highly polluted mainly due to the suspended particulate matters, which encompasses a wide spectrum of chemical elements. These elements based on their type, size, and impact on the life cycle have various environmental and heath risks. In this research, the neutron activation method is used to determine the concentration levels of Al, Ba, Fe, Mg, and V in the urban air. Thus, two districts of Tehran with different characteristics are selected. District 21 includes much of the industries located in Tehran metropolitan and is considered as an industrial area. In contrast, district 22 lacks any significant industrial activity. It is a newly established and expanding district adjacent to district 21 with a great deal of constructional activities. For the measurement of the suspended particulate matters in the air, the various sections of the aforesaid districts with industrial, residential, heavily congested traffic, residential/commercial, residential/heavily congested traffic, and residential/industrial classifications were identified. Subsequently, 24 sampling stations were selected. The sampling of the suspended particulate matters was conducted with the aid of a high volume pump containing 125 mm cellulose filters in two different time intervals. After completion of the sampling process, the samples were prepared and sent to the research reactor of the Iran Nuclear Energy Organization for Neutron Activation. During the next steps, the radiations emitted from the samples were registered, the radiation curves were plotted, and the amounts of the trace elements were determined. As a result, the average concentration levels of Al, Ba, Fe, Mg, and V were identified to be 3.301140, 2.273658 × 10, 4.0681696 × 10 − 1, 3.5525475 × 10 − 1, and 3.04075 × 10 − 2 μg/m3, respectively. Moreover, the emission sources of the aforesaid elements into the air were identified. The concentration levels of these elements in the industrial and heavily congested traffic sections were higher. Finally, it was concluded that the statistical analysis of these elements presents a meaningful correlation among them.