A MATLAB-based visualization package for planar arrays of isotropic radiators

This article introduces a simple MATLAB antenna package (ANTEN/spl I.bar/GUI) for the visualization of the radiation patterns, beamforming, and beam-steering capabilities of user-designed planar arrays of isotropic radiators. The package can be used as an educational aid, especially in antennas and propagation lectures.     

An intelligent balance

This paper discusses the intelligent balance, which has been established between real and virtual experiments and it also gives skills that have not covered in conventional electronics and communication engineering. Engineering is the art of applying scientific and mathematical principles, experience, judgment and common sense to make things that benefit people. The explosive growth of computer capabilities and easy access to nanominiature devices has revolutionized communication and the analysis of complex systems. The EC engineer either individually or as a member of a team, can play an important role in this technical diverse mosaic and this community prepares to adapt frequency shifts in technical priorities. EC engineers should be given computers hand-on-practice and training and also should understand the physics of the problem and fundamental theorem.     

Boron containing UV-curable epoxy acrylate coatings

In the present work boron acrylate monomer was synthesized by esterification reaction. UV-curable boron containing epoxy acrylate coatings were prepared and applied on plexiglass substrates to obtain thermally and mechanically stable coatings. The physical and mechanical properties of UV-cured coatings were investigated such as gel content, solvent resistance, hardness, flexibility and tensile tests. The thermal behavior of coatings was also evaluated. It was observed that the tensile properties and thermal stabilities of boron modified epoxy coatings mainly depend on the boron content.     

Determining Attribute Weights in a CBR Model for Early Cost Prediction of Structural Systems

This paper compares the performance of three optimization techniques, namely feature counting, gradient descent, and genetic algorithms (GA) in generating attribute weights that were used in a spreadsheet-based case based reasoning (CBR) prediction model. The generation of the attribute weights by using the three optimization techniques and the development of the procedure used in the CBR model are described in this paper in detail. The model was tested by using data pertaining to the early design parameters and unit cost of the structural system of 29 residential building projects. The results indicated that GA-augmented CBR performed better than CBR used in association with the other two optimization techniques. The study is of benefit primarily to researchers as it compares the impact attribute weights generated by three different optimization techniques on the performance of a CBR prediction tool.     

Sustained-Release Dosage Form of Nicardipine Hydrochloride: Application of Factorial Design and Effect of Surfactant on Release Kinetics

Microcapsules of nicardipine hydrochloride with core:wall ratios of 1:1, 2:1, and 1:2 were prepared by the coacervation-phase separation method, using ethyl-cellulose as the coating material. Two batches of nicardipine hydrochloride microscapsules were divided into size fraction by using standard sieves ranging from 840 μm to 476 pn. Dissolution rate studies from microcapsules were performed using the USP XXII basket method. The kinetic model according to the Rosin-Rammler-Sperling-Bennet-Weibull (RRSBW) distribution was applied for the parametric representation of the dissolution curves. Preparation and dissolution rate studies on the nicardipine hydrochloride microcapsules were pellformed and the influence of particle size, core:wall ratio, and the amount of nicardipine hydrochloride on the release rate was examined by 2³ factorial design. The sign@cance of the observed effects was tested with the F test. A surface active substance was added in the dissolution medium to understand how this substance effects the release of drug from ideal microcapsule form which is found by the findings of the 2³ factorial design. Dissolution studies were repeated with this ideal formulation using different ratio of Tween 20.

The results of this study suggested that the solubility and bioavailability of the sustained-release dosage forms of nicardipine hydrochloride using sullface active substances could be increased.     

Psychosocial aspects of genital herpes virus infection.

Reviews studies of psychosocial aspects of genital herpes virus infection. The fact that no cure is yet available has contributed to the heightened emotions caused by this sexually transmitted disease. Significant moral overtones exist for many people, and powerful social stigma are associated for many. Depression, anger, hostility, and reduced self-esteem have been reported among herpes sufferers. Alterations in sexual activity are common. The relationship between stress and recurrence has been examined. Results, although not fully conclusive, support the role of stress and emotional factors in the disease process. In terms of areas of future research, the interactive role of behavioral, emotional, and social variables and the immune system must be examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Microstructure and ionic conductivity properties of gadolinia doped ceria (GdxCe1−xO2−x/2) electrolytes for intermediate temperature SOFCs prepared by the polyol method

Gd_0.1Ce_0.9O_1.95 and Gd_0.2Ce_0.8O_1.9 powders were prepared through the polyol process without using any protective agent. Microstructural and physical properties of the samples were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TG) and impedance analysis methods. The results of the thermogravimetry/differential thermal analysis (TG/DTA) and XRD indicated that a single-phase fluorite structure formed at the relatively low calcination temperature of 500 °C. The XRD patterns of the samples revealed that the crystallite size of the samples increased as calcination temperatures increased. The sintering behavior and ionic conductivity of pellets prepared from gadolinia doped ceria (GDC) powders, which were calcined at 500 °C, were also investigated. The relative densities of the pellets, which were sintered at temperatures above 1300 °C, were higher than 95%. The results of the impedance spectroscopy revealed that the GDC-20 sample that was sintered at 1400 °C exhibited an ionic conductivity of 3.25×10⁻² S cm⁻¹ at 800 °C in air. This result clearly indicates that GDC powder with adequate ionic conductivity can be prepared through the polyol process at low temperatures.     

Influence of Cape gooseberry (Physalis peruviana L.) addition on the chemical and sensory characteristics and mineral concentrations of ice cream

In this research, the influence of Cape gooseberry (CG) addition at different concentrations (5, 10 and 15%) on the physical, chemical and sensory properties and mineral contents of ice cream was investigated. The increment of CG concentration caused the decrease of fat, protein, pH and overrun values in ice cream, on the contrary it increased the total solid, ash, titratable acidity, viscosity values and first dripping and complete melting times. S contents of ice creams significantly increased with the CG addition. Moreover, CG increased K, and Na concentrations of ice cream, while lowered Ca and P contents. Mg contents of ice creams didn't change with CG addition (P > 0.05). Fe, Zn, Mn and Ni were determined as minor elements in ice cream samples and a significant increase was observed in Fe, Zn and Mn values (P < 0.05). The addition of CG did not affect Ni content of ice creams. The sensory results indicated that the ice cream containing 15% CG was the highest-scored by the panelists.