This paper derives an optimal inventory replenishment policy for two parameters Weibull deteriorating items with a permissible delay in payment under   inflation over finite planning horizon. The theoretical results reflected in this paper is also studied through numerical examples and sensitivity analysis.

Given the anticipated benefits of better solutions, the scheduling problem of minimizing the total tardiness for single machine with sequence dependent setup times continues to represent a challenge for researchers to resolve. This research presents a novel Max-Min Ant System (MMAS) algorithm for solving this problem. The MMAS algorithm adopts a new local search technique where, a position is randomly chosen from the jobs' sequence and the job located at this position is either interchanged with other jobs or another job from the sequence is inserted in this position. The best move is chosen and the algorithm is repeated. The new algorithm has been tested on a number of benchmark problems for both the weighted and the unweighted tardiness and the experimental results show that the algorithm can reach better results on most of the cases.   

In this paper, the homotopy perturbation method (HPM) which doesn’t small parameter is applied to solve the linear and nonlinear parabolic equations. The HPM deforms a difficult problem into a simple problem which can be easily solved. It is implemented with appropriate initial conditions. Comparison of the applied methods with exact solutions reveals that the method is tremendously effective.

In this numerical study, performance of Ranque-Hilsch vortex tubes, with a length to diameter ratios (L/D) of 8, 9.3, 10.5, 20.2, 30.7, and 35 with six straight nozzles, on the basis of available experimental results were investigated. Also, this study has been done to understanding the physical behavior of the flow field in the vortex tube. CFD analysis is employed to achieve the highest temperature separation and optimum length to diameter (L/D) ratio of the Ranque–Hilsch vortex tubes. The temperature separation phenomenon in the vortex tube has been obtained by a 3D compressible turbulent CFD model. Also it was found that the best performance was obtained when the ratio of vortex tube’s length to the diameter was 9.3. Moreover, it is found that increasing the cold mass fraction decreases the cold temperature difference and efficiency. Finally the computed results such as velocity and temperature variations are presented and discussed in more details. Presented results in this paper shown good agreement with experimental results.

Two types of mucoadhesive suspension of Ciprofloxacin were formulated by taking Carbopol934 and Carbopol940 polymers. The morphologies and mechanical properties of the resultant formulations were investigated. The dispersion of particle was observed using Scanning electron microscopy (SEM) techniques. The particle size distribution (PSD) and aspect ratio (AR) of particles in the polymeric suspension were obtained from SEM image analysis. It was found that SEM imaging displays directly the micron level dispersion of particles in polymeric formulation. The technique has significant potential for characterizing such formulation, having some advantages over ‘traditional’ transmission electron microscopy in terms of generating representative data in a realistic timescale. Considering graphical analysis, the maximum particle size range for formulation containing Cipro and C934 is between 10 and 15 µm but in case of Cipro and C940, it is 5 to 10 µm.  In the rod-like particles whose shapes are characterized by the two major and minor lengths of the particle, the length/width ratios are satisfactorily consistent with the aspect ratio value evaluated from the instrumental measurements. Formulation containing Cipro and C934 is more stable because it has lesser standard deviation and co-efficient of variation in aspect ratio analysis. The PSD and AR distribution and degree of dispersion in the formulation give insights into the modification of mechanical properties of the mucoadhesive formulation studied.

An efficient scheme to reduce peak to average power ratio (PAPR) of OFDM signal is presented, which introduces bandwidth efficiency increasing method to OFDM. In other words the spacing of the sub-carriers in this new method is twice as dense when compared to conventional OFDM system.  In this new method the frequency separation of the sub-carriers is halved compared to the conventional OFDM. It is evident from simulation results that the new technique has significantly reduced the PAPR for high data rate systems. This improvement in the systems performances have been maintained even when different combination modulation scheme and number of subcarrier were used. Using statistical hypotheses testing with confidence level 95%, we have sufficient evidence that the proposed method is better than the conventional OFDM system.

Radon gas with chemical symbol Rn222 is the heaviest element radioactivity, colorless, odorless, tasteless, heavy and noble. Radon naturally in rocks and soils and waters is available and because there is no affinity to plead easily by soil and water molecules into the air and is moving. Radon enters the body with breathing, eating and drinking. Alpha, which is emitted from radon and other nuclear radiations, sent by its daughters nucleus, serious damage to human respiratory and gastrointestinal system brings, so after smoking, the second risk factor in lung cancer is radon radiation. Radon gas density varies due to factors such as temperature, air pressure, humidity and changes in ground layers. As a result, radon gas densities in the seasons are different. In this research, water radon concentration of 10 point Shandiz area in different seasons of the year with the help PRASSI system is measured. Fortunately, the results show that only two samples of drinking water are higher than normal density Bq / l 11.1 in the fall.

The analyses of self and mutual impedances and voltage distributions of 8dBi Modified Driven Array of Dipoles Antenna at UHF/L (850 – 1150MHz) band using hybrid frequency domain moment method have been presented in this paper. The results of the analyses indicated that the currents distributions lead the voltages distributions in the proposed antenna, and the antenna has the ability to dissipate little or no energy loss as heat, all the energy received by the antenna will be expended as radiation resistance. The antenna’s voltages distributions reached the maximum peak values at 1000MHz and 1150MHz resonant frequencies. The analyses also confirmed the supreme performance of the dipole antenna array as compare to the single element dipole antenna in agreement with the previous work by other scientists and engineers. Here, the peak values  (maximum of 80±0.1mV and minimum of 70±0.1mV) reached by the voltages distributions of the proposed antenna array are much greater than that of the individual dipole element of the antenna (maximum of 13±0.1mV and minimum of 6.5±0.1mV) at the same resonant frequencies of 1000MHz and 1150MHz. The computed Voltage Standing Wave Ratio (VSWR) is ~1.0 at the frequency band of consideration, and the bandwidth is ±10% of the resonant frequency which doubles ±5% of the individual dipole element of the proposed antenna array at the same resonant frequency.