this study aimed to evaluate the potential of image ratioing techniques to detect and map the extent and particle composition of sand dunes in the erg of gavkhouni in isfahan province. the 6/4 ratio index and also a new index called sadi which was calculated using landsat band 3, 6 and 7 were applied to a georeferenced landsat tm image. to evaluate the performance of ratio techniques, the extra...

A tunable dual-band inverted F antenna (IFA) is presented in this paper. By placing a LC resonator on the radiating arm, dual-band characteristic is achieved. Especially, the capacitor in the resonator is a tunable thin-film BST capacitor, which has a 3.3:1 tuning ratio. The capacitance of the BST capacitors can be tuned by an external DC bias voltage. By varying the capacitance, both the lower...

Band structure parameters, such as the band gap, can be estimated using electrical transport properties. In many thermoelectric studies, the temperature dependent Seebeck coefficient is used to estimate the band gap using the Goldsmid–Sharp band gap formula: Eg 1⁄4 2eSmaxTmax. This important, fundamental parameter is useful for characterizing and understanding any semiconductor, but it is parti...

OFDM transmission in optical wireless channel is established via asymmetrically clipped optical OFDM (ACO-OFDM). Clipping is one of the simplest methods to reduce the high peak to average power ratio (PAPR). Clipping leads to additional in-band distortion and out-of band distortion. In this paper it is proposed to mitigate the clipping noise by iterative reconstruction based method and Channel ...

This article presents the design of a novel dual-band signal cancellation circuit and its application to feedforward linear power amplifier. Intermodulation distortion cancellation loop shows 20.45 dB and 25.04 dB suppression for digital cellular band and IMT-2000 band, respectively, over a correction bandwidth of 100 MHz. From the adjacent channel leakage ratio measurement, 16.5 dB and 18.6 dB...

OBJECTIVE To determine whether the immature neutrophil (band) count in the peripheral blood smear helps to distinguish young febrile children with bacterial or respiratory viral infections. DESIGN AND SETTING A prospective cohort study in 3 pediatric emergency departments. PATIENTS A convenience sample of 100 febrile children aged 2 years or younger with either laboratory-documented bacteri...

This paper presents the development of an Ultra Wide Band (UWB) monopole antenna with dual band notch characteristics. Modified crown-square shaped fractal slots in the ground-plane are implemented to enhance the impedance bandwidth to around 58% as compared to conventional square monopole antenna without slots. Impedance bandwidth of the proposed antenna is approximately 114% with Voltage stan...

ZnO/GaN alloys have exceptional photocatalytic applications owing to their suitable band gaps corresponding to the range of visible light wavelength and thus have attracted extensive attention over the past few years. In this study, the structural stabilities and electronic properties of core/shell, biaxial, and super-lattice ZnO/GaN heterostructured nanowires have been investigated by means of...

In this article, a simple and compact dual bandnotched (DBN) super wideband (SWB) printed monopole antenna (PMA) has been proposed. The proposed antenna composed of a circular PMA, which is connected through a 50-Ω triangular tapered microstrip fed line (TTMFL) and a round-cornered finite ground plane (RCFGP). It exhibits a very wide frequency band from 1.6–25 GHz (ratio bandwidth of 15.63:1) w...

AbstructThe space shuttle orbiter (SSO) Ku-band single access return (KSAR) link and the space station freedom (SSF) KSAR link' via the tracking and data relay satellite system (TDRSS) use the same carrier frequency. The interference between spacecraft is minimized by opposite antenna polarizations and by TDRSS antenna beam pointing, but if the SSF and SSO are in close proximity, it is expected...