Search

The article presents the synthesis and liquid crystalline properties of some of new bent and linear core compounds containing a 1,3,4-oxadiazole, piperazine and thiazolidin-4-one rings as a central...

In this article, the influence of variable thermal conductivity and Hall current is investigated for elastic semiconductor medium. The medium is linear and exposed to a very strong magnetic field w...

In this problem, the photothermal excitation processes and thermal conductivity of a semiconducting elastic medium due to the change in the temperature effect are studied. The dual-phase-lag (DPL) ...

The main goal of this paper is to develop a mathematical model for the piezoelectric elastic-semiconductor medium. The medium is homogeneous and isotropic that is exposed to photothermal excitation...

We aimed to prospectively study the demography, severity of injury and outcome of alcohol-related road traffic collision (RTC) injuries in the United Arab Emirates.Data of RTC Registry of Al-Ain City were prospectively collected from Al-Ain and Tawam hospitals during the period of April 2006 to October 2007. It included all RTC trauma patients who were admitted or those who died after arrival to these hospitals. Car occupants with complete data on alcohol use were included in the study. Patients were divided into two groups, those who reported using alcohol and those who did not.Out of the 771 car occupants, sixteen (16) used alcohol (2.1%), 15 (94%) of them were males. The median (range) age of the alcohol group was significantly higher than those without alcohol (35 (15-53) years compared with 26 (1-78) years, p = 0.02). The UAE nationals were significantly more (P = 0.01) and the revised trauma score was significantly less in the alcohol group (P = 0.03). Head/face was the most commonly injured region in the alcohol group (94%).Self reported alcohol-related car collisions in Al-Ain City had a low incidence. It affected older Emirati male nationals and was associated with lower revised trauma score, mainly due to head injury. There is a need for a national registry with data on alcohol abuse so as to assess its effects and strategies for its prevention.

The problem of electromagnetic TE scattering by an infinitely long conducting cylinder coated with an inhomogeneous dielectric/magnetic material is analyzed. A volume-surface integral equation (VSI...

The numerical implementation of Green's functions is a fundamental step for analyzing multi-layered media applications. The computation time and the accuracy of results, which should be maintained for all field regions, are two crucial issues. The discrete complex image method is one of the methods that proved its efficiency in accelerating the computation time and yielding accurate results in the near- and intermediate-field regions. In order to retain this accuracy for the far-field region, the surface-wave contribution should be extracted. However, this procedure results in erroneous results in the near field. This article is concerned with the nonsymmetrical components of the magnetic vector potential. Two different approaches to handle this problem are analyzed. In both approaches, additional artificial poles are extracted in order to eliminate the problem of contaminated results in the near field. The results of both approaches are presented, and the effect of these artificial poles is expl...

In this paper a neural network model is presented for solving the two-dimensional inverse scattering problem of a metal strip. The proposed model estimates the location of the strip based on the back-scattering field measurements at a few distant points. A radial basis functions neural network is adopted. Besides its remarkably fast response, the proposed model is capable of estimating the location of the strip with very high accuracy.

The Green's function for multilayered media is expressed in terms of Sommerfeld integrals. The discrete complex image method is an appealing technique in handling such integrals. However, the results of the nonsymmetrical components lacks sufficient accuracy in the near-field region. This is due to the fact that these components have slowly varying spectral-domain behavior. In this work, the quasi-dynamic contribution is explicitly extracted. The remaining part has fast decaying behavior. The generalized pencil-of-function method is used to recast this part into a set of exponentials. Using a special identity, a closed-form expression is obtained that is valid in the near-field region. The method is demonstrated to yield accurate results for microstrip structures.

Nitrogen and potassium fertilization and plant spacing affected seed yield and seed content of the active, antiheptotoxic flavonolignans silybin (silymarin), silidianin, and silicristin of Silybum marianum(L.) Gaertn. A narrow row spacing (25cm) produced higher yields of seeds, but reduced oil and flavonolignan content as compared with a wide row spacing (50cm). Potassium fetilization at 115 kg K2O/ha and nitrogen fertilization at 140 kg N/ha increased seed yield, oil yield, and percent oil, and flavonolignan content of seeds as compared with lower rates of fertilization. Cultivation of Silybum marianum at spacing of 50 cm between rows and with fertilization at 55 kg K2O/ha yielded the highest percentage of silybin in Silybum marianum seeds. Nitrogen had no effect on the percentage of silybin seeds at the 2 levels tested.

The integral equations governing the electromagnetic scattering by bodies of revolution involve the computation of what are called the modal Green's functions. These functions are evaluated repeatedly. Hence, any saving in time while computing these functions will be reflected on the overall time of computation. These functions are usually evaluated using an adaptive numerical integration technique. In this work, an exact series form is obtained to efficiently evaluate these functions. An acceleration technique is used to speed up the series convergence. The method can be implemented in existing codes. It is shown that a significant saving in the time of computation is achieved using the series form.

This work presents a new formulation for conducting bodies of revolution (BOR) in layered media. It is derived using magnetic field integral equation (MFIE). The discrete complex image method is used to transform the Sommerfeld integrals into closed form solutions. For large closed objects, the use of the magnetic field formulation is shown to be more advantageous than the electric field integral equation (EFIE) concerning the convergence of the solution. The obtained formulation is applied to the contiguous half-spaces case. Results of both the magnetic and electric field integral equation formulations are presented.