Cyclostationary feature detection is one of the most powerful spectrum sensing techniques used for cognitive radio (CR) systems. This is because of its robustness against noise uncertainties. However, this technique needs high sampling rates, which is limited by the state-of the-art analog to digital converters (ADCs), especially in wideband regime. Comressive sensing (CS) was used by many researchers for solving this problem via sub-Nyquist sampling rates. However CS solves the high sampling rate problem, but it does not reduce complexity considerably. This is because spectrum sensing is performed in three steps: sensing compressed measurements, then reconstructing the Nyquist rate signal, and finally performing cyclostationary detection (CD) on the reconstructed signal. In this paper we suggest performing CD directly on the compressed measurements skipping the reconstruction step which is the most complex step in CS. This can be realized by designing the sensing matrix with constraints different from those used in the conventional CS. Results show that performance is improved relative to applying CD on the Nyquist rate signal. This is in addition to reduction in receiver complexity resulting from reducing sampling rates. A detection probability of 78.7% can be achieved with only 7% of samples used by the conventional cyclostationary detection technique that achieves a detection probability of 32.7%.

Optimal computation of parameters and placement of UPFC based minimization of New Voltage Stability Index (NVSI) are presented in this paper. The application of Unified Power Flow Controller (UPFC) to enhance transient stability of a multi-machine power system is listed. A supplementary stabilizer based on UPFC (like power system stabilizer) is designed to reach the defined purpose. Phase Angle Particle Swarm Algorithm (θ-PSO) is usedas an optimization method. Several nonlinear time-domain simulation tests visibly show UPFC capability in damping of power system oscillations and consequently transient stability betterment. Comparisons based system transient stability enhancement among different UPFC locations and parameters are introduced. The effectiveness of the proposed method is analyzed with IEEE 14-bus and IEEE 30-bus test systems.

Using of false ceilings (FC) for decoration and covering different ducts in modern buildings is spreading so much nowadays. This paper tries to find a new employment and other benefits for using false ceilings (FC).A one dimensional transient mathematical model has been established to study the effects of using false ceiling on reduction of heat gained from concrete roof of controlled temperature space. The effect of using false ceiling (FC), with and without adding reflector sheet on its upper side facing to concrete roof on the room cooling load is studied by modeling and solving the transient heat transfer processes in the different components of the space. The results showed that using of false ceiling only without reflector sheet reduces heatgain introduced to space through 24 hours by 66.8%, while using of false ceiling with reflector sheet increases the reduction percent of heat gained from concrete roof to be 81.6% for the same period.

Retrofitting the seismically deficient structures before earthquakes provides a feasible approach to improve their load carrying capacity and reducing their vulnerability. This study presents an analytical assessment investigation on hollow block slab reinforced concrete building. The building is not designed according to seismic standards; moreover, hollow block slab systems may lack the sufficient lateral seismic resistance. Different retrofitting systems to enhance the seismic capacity of the target building are proposed and evaluated. These systems include strengthening the columns with reinforced concrete jackets or using internal shear walls or introducing steel chevron bracing. The target building before and after retrofitting is analyzed either as bare frames or considering masonry infill walls with different parameters. The three dimensional nonlinear pushover analysis procedures are used in evaluating the seismic performance of the original building and the retrofitted ones. The demand response spectra proposed by the Egyptian Code of Loads, ECOL 201, 2012 edition, for different seismic zones with different soil properties are utilized in the evaluation. Real seven earthquakes response spectra with maximum-scaled spectrum acceleration close to the one calculated for Cairo city are also applied. It is found that the original target building, before retrofitting, fails to fulfill the demands of neither many of the ECOL response spectra nor many of the applied real earthquakes. All the proposed retrofitting systems succeed in highly enhancing the seismic capacity of the original building. Considering masonry infill walls in the analysis has a crucial role on the seismic performance of the original building, the retrofitting systems can, due to the increase in the lateral strength, limit this effect.

Using of false ceilings (FC) for decoration and covering different ducts in modern buildings is spreading so much nowadays. This paper tries to find a new employment and other benefits for using false ceilings (FC).A one dimensional transient mathematical model has been established to study the effects of using false ceiling on reduction of heat gained from concrete roof of controlled temperature space. The effect of using false ceiling (FC), with and without adding reflector sheet on its upper side facing to concrete roof on the room cooling load is studied by modeling and solving the transient heat transfer processes in the different components of the space. The results showed that using of false ceiling only without reflector sheet reduces heatgain introduced to space through 24 hours by 66.8%, while using of false ceiling with reflector sheet increases the reduction percent of heat gained from concrete roof to be 81.6% for the same period.

In this paper, a D-Q model of fuzzy based unified power flow controller (UPFC) has been proposed to control the active and reactive power flow through the transmission lines. Power loss reduction also intends with the proposed UPFC controller. The UPFC's shunt and series controllers are developed based on D-Q fuzzy logic (FL) controller, which has been designed in PSCAD environment as an independent module. The proposed UPFC controller is tested by using IEEE-5 and 14 bus systems. The performance of D-Q fuzzy based UPFC reveals better improvement compared to PI based UPFC in terms of power flow control and power loss reduction.

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The composite coating of a titanium carbide aluminide–alumina-iron composite was synthesized by centrifugal-assisted self-propagating high-temperature synthesis (SHS). The in situ TiC–Al2O3–Fe with intermetallic phases of titanium aluminide (TiAl/Ti3Al) possesses excellent metallurgical properties. This composite was produced from compacted titanium (Ti) and carbon (C) powders in the form of pellets embedded in a tube, which were exposed to very high temperature generated by the thermite Fe2O3 and Al reaction. The process took place in a graphite–steel tube mounted in a centrifugal accelerator machine purposely developed for this function. Functionally graded coating was produced under the centrifugal acceleration field and the product of the thermite reaction (Al2O3 and Fe) infiltrated the TiC pellet and to create a strong, titanium aluminide intermetallic layer. The centrifugal force significantly enhanced both metallurgical alloying and mechanical interlocking between different sample layers during product formation. The purpose of the research addresses the applications of local reinforcement of the ceramic-lined tubes.