Linear antenna Arrays are synthesized to have maximum directivity for a Specified Beamwidth. The directivity is maximized subject to a given Beamwidth such as null to null or half power one. The excitation currents are obtained using a matrix equation obtained from the Lagrange multiplier method. The performance of the proposed method is studied by means of some examples. The synthesized Arrays have the pre-Specified beamwhidths and their directivity is close to the number of elements.

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Mammary sarcomas are a heterogeneous group of malignant neoplasms that arise from the mammary stroma. Primary sarcomas of the breast are extremely rare and comprise less than 0.1% of all malignant tumors of the breast. We present the case of a 56-year-old female diagnosed as stromal sarcoma, not otherwise Specified - a very rare entity.

Supplying the energy demanded by spacecraft and satellites is an ever-increasing need. As a result, it is an active field in developing space technologies. In addition to the commonly used rigid substrate solar Arrays, flexible substrate and concentrator solar Arrays are other available categories. This paper reviewed the developments and commercial technologies in each category. The flexible solar Arrays, implemented in several spacecraft during the last two decades, have recently attracted attention in satellites. It seems that these Arrays will replace rigid Arrays in the near term due to their higher specific power and smaller stow volume than rigid Arrays.

The class of Hybrid Linear and Circular Antenna Arrays is presented. The properties of linear and circular antenna Arrays are combined to obtain hybrid array types: concentric circular, cylindrical, and coaxial cylindrical antenna Arrays. These three types are defined, the expressions of their array factors are derived, their directivities and half power beam widths (HPBW) are simulated. The obtained plots are approximated by curve fitting. Different combinations of excitation currents (e.g. uniform, Chebyshev, Bessel, …) can exist on the elements of the same antenna array.

the increasing importance of the need for electricity and the need to have a healthy and pollution-free environment have prompted researchers to constantly track renewable sources of energy such as wind, solar, geothermal and so on instead of fossil fuels. But technology is not advanced enough yet to utilize them, and the costs associated with setting up and implementing them is not reasonable. In order to find and complement new methods to employ renewable energy, this paper investigates a new generator, i.e., Kite-Gen. The idea first explored in Torino, Italy, and is now being studied around the world. One of the most important factors to produce the maximum energy in a specific Kite-Gen, is to control its direction in a correct way. The purpose of this paper is to find a feedback control and to obtain proper eigenvalues for zero steady-state error.