Baku, Azerbaijan
Baku, Azerbaijan

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Sardarly R.M.,Azerbaijan Academy of Sciences | Badalov A.Z.,National Academy of Aviation | Abdullaev A.P.,Azerbaijan Academy of Sciences | Vezirova T.N.,National Academy of Aviation | And 3 more authors.
Physics of the Solid State | Year: 2016

Vibrational spectra of TlInS2 crystals in the terahertz frequency range (0.1–3 THz) have been obtained and analyzed. The observed low-frequency band is attributed to the libration oscillations of nanolayers (so-called boson peak). A correlation between the coherent low-frequency oscillation and a disordered character of the crystal structure is shown. A conclusion is made on the presence of a topological disorder that manifests itself on the layered subsystem level. © 2016, Pleiades Publishing, Ltd.

Eyvazova S.A.,Azerbaijan State Advanced Training Institute For Doctors Named After A Aliyev | Safarzade A.A.,National Academy of Aviation | Musayev G.C.,Azerbaijan Medical University
Azerbaijan Medical Journal | Year: 2012

The article presents the results of studying skin squamous epitheoliocytes and mucos of bladder from human papillomavirus-infected female patients by cytology and atomic force microscopy. It was established cytomorphology signs papillomavirus infection which have completely topographic differentiation from the normal surface of cells. Using the AFM we received the information about squamous epitheoliocytes with and without cytomorphological signs of papillomavirus infection (coilocytosis, dyskeratosis, parakeratosis).

Tagiev B.G.,National Academy of Aviation | Tagiev B.G.,Azerbaijan Academy of Sciences | Abushov S.A.,Azerbaijan Academy of Sciences | Asadov E.G.,Azerbaijan Academy of Sciences | And 3 more authors.
Crystallography Reports | Year: 2015

Photoluminescence (PL) excitation and emission spectra of Ca(AlxGa1–x)2S4:Eu2+ (х = 0.1, 0.2) crystals have been investigated at different temperatures (20–300 K) and europium concentrations (3, 5, 7%). The emission spectrum is a band peaking at 556 nm, which is due to 4f65d → 4f7(8S7/2) transitions in the Eu2+ ion. An increase in the Eu2+ concentration leads to an increase in the PL intensity by a factor of almost 3. Stokes shift ΔS = 0.32 eV, Huang–Rhys factor s = 10 ± 2, activation energy Еа = 0.02 and 0.03 eV, and lifetime τ = 250 ns are determined by analyzing the spectra. © 2015, Pleiades Publishing, Inc.

Tagiev B.G.,Azerbaijan Academy of Sciences | Tagiev B.G.,National Academy of Aviation | Abushov S.A.,Azerbaijan Academy of Sciences | Tagiev O.B.,Azerbaijan Academy of Sciences | Tagiev O.B.,Baku State University
Optics and Spectroscopy (English translation of Optika i Spektroskopiya) | Year: 2016

The photoluminescence (PL) and PL excitation spectra of CaGa2S4 polycrystals doped with praseodymium are studied in the regions of the activator absorption and the fundamental absorption of the host. It is found that the PL excitation spectrum consists of two regions: broadband absorption in the range of 200-380 nm corresponding to the fundamental absorption of the host and the narrow-band absorption of the dopant in the range of 430–515 nm. The luminescence spectra are different for different excitation wave-lengths, which occurs because Pr3+ ions substitute divalent cations occupying different crystallographic positions in the host crystal lattice. © 2016, Pleiades Publishing, Ltd.

Pashaev A.M.,National Academy of Aviation | Pashaev A.M.,Azerbaijan Academy of Sciences | Tagiev B.G.,National Academy of Aviation | Tagiev B.G.,Azerbaijan Academy of Sciences | And 2 more authors.
Physics of the Solid State | Year: 2013

The results of investigation of electrical conductivity of a large group of chalcogenide semiconductors having the layered, cubic, and orthorhombic structures in strong electric fields up to 105 V/cm are presented. The revealed increase in electrical conductivity σ in strong electric fields has been explained by the Frenkel thermionic ionization. This has made it possible, along with other parameters (for example, activation energy and trap concentration, charge-carrier mean free path, permittivity), to evaluate the concentration and mobility of charge carriers in semiconductors under study. It has been shown that in strong electric fields in semiconductors, when the thermionic ionization of the traps occurs, their permittivity e{open}, which is caused by the electron polarization, is determined by the simple formula e{open} = n2, where n is the refractive index of light. © 2013 Pleiades Publishing, Ltd.

Aida-Zade K.R.,Azerbaijan Academy of Sciences | Ardil C.,National Academy of Aviation | Sharifova A.M.,National Academy of Aviation
World Academy of Science, Engineering and Technology | Year: 2010

In this paper, the main principles of text-to-speech synthesis system are presented. Associated problems which arise when developing speech synthesis system are described. Used approaches and their application in the speech synthesis systems for Azerbaijani language are shown.

Mekhtiev A.S.,National Academy of Aviation | Abdullaev N.A.,Research Institute of the Defense Industry Ministry | Asadov K.G.,Research Institute of Aerospace Information Science
Russian Journal of Nondestructive Testing | Year: 2014

Problems of the design criteria for comparing two possible versions of the trilateration approach to acoustic location are considered, viz., a location method based on measuring the amplitude of the signal and a location method based on measuring distances from receivers to a sound source. It is shown that when some conditions are met and the noise in the signal is low it can be preferable to select the method that is based on measuring the amplitude of the implementation signal of the trilateration approach for locating the source of an acoustic signal. © 2014, Pleiades Publishing, Ltd.

Mishra S.K.,NIST Berhampur | Panda S.,NIST Berhampur | Padhy S.,Prasar Bharati Broadcasting Corporation of India | Ardil C.,National Academy of Aviation
World Academy of Science, Engineering and Technology | Year: 2011

In this paper, real-coded genetic algorithm (RCGA) optimization technique has been applied for large-scale linear dynamic multi-input-multi-output (MIMO) system. The method is based on error minimization technique where the integral square error between the transient responses of original and reduced order models has been minimized by RCGA. The reduction procedure is simple computer oriented and the approach is comparable in quality with the other well-known reduction techniques. Also, the proposed method guarantees stability of the reduced model if the original high-order MIMO system is stable. The proposed approach of MIMO system order reduction is illustrated with the help of an example and the results are compared with the recently published other well-known reduction techniques to show its superiority.

Khuntia S.R.,Indian National Institute of Engineering | Mohanty K.B.,Indian National Institute of Engineering | Panda S.,U.S. National Institute of Standards and Technology | Ardil C.,National Academy of Aviation
World Academy of Science, Engineering and Technology | Year: 2010

This paper presents a comparative study of various controllers for the speed control of DC motor. The most commonly used controller for the speed control of dc motor is Proportional- Integral (P-I) controller. However, the P-I controller has some disadvantages such as: the high starting overshoot, sensitivity to ontroller gains and sluggish response due to sudden disturbance. So, the relatively new Integral-Proportional (I-P) controller is proposed to overcome the disadvantages of the P-I controller. Further, two Fuzzy logic based controllers namely; Fuzzy control and Neuro-fuzzy control are proposed and the performance these controllers are compared with both P-I and I-P controllers. Simulation results are presented and analyzed for all the controllers. It is observed that fuzzy logic based controllers give better responses than the traditional P-I as well as I-P controller for the speed control of dc motor drives.

Gasanov A.R.,National Academy of Aviation | Gasanov R.A.,National Academy of Aviation
Radioelectronics and Communications Systems | Year: 2015

This paper presents the physical and mathematical interpretation for the sequence of the response formation at the output of the acousto-optic delay line direct detection for various forms of connected to the terminals electro-acoustic transducer of high-frequency vibration. It has been shown that for the chosen design the intensity of light, which is incident on the photosensitive surface of the photodetector, varies only in the case of a change of acoustic power in the photoelastic medium. This eliminates the possibility of using the angular modulation for the transfer of video signal spectrum in the range of operating frequencies of the acousto-optic modulator in acousto-optic delay line with direct detection. In order to provide such a possibility it is recommended to install on the path of the deflected light a reference indicator, which converts the changes in the angle of diffraction into corresponding changes in the intensity of light, which is incident on the photosensitive surface of the photodetector. The proposed design is investigated for square and circular apertures of the light beam. It has been determined that best results are achieved in the case of the light beam with a square aperture and with a uniform distribution of power flow therein. We present the main results of experimental studies that confirm the effectiveness of the proposed design. © 2015, Allerton Press, Inc.

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