1,733,042 research outputs found
A low-voltage low-power instrumentation amplifier based on supply current sensing technique
No full textMinaei, Shahram (Dogus Author)In this paper a new low-voltage low-power instrumentation amplifier (IA) is presented. The proposed IA is based on supply current sensing technique where Op-Amps in traditional IA based on this technique are replaced with voltage buffers (VBs). This modification results in a very simplified circuit, robust performance against mismatches and high frequency performance. To reduce the required supply voltage, a low-voltage resistor-based current mirror is used to transfer the input current to the load. The input and output signals are of voltage kind and the proposed IA shows ideal infinite input impedance and a very low output one. PSPICE simulation results, using 0.18 μm TSMC CMOS technology and supply voltage of ±0.9 V, show a 71 dB CMRR and a 85 MHz constant −3 dB bandwidth for differential-mode gain (ranging from 0 dB to 18 dB). The output impedance of the proposed circuit is 1.7 Ω and its power consumption is 770 µW. The method introduced in this paper can also be applied to traditional circuits based on Op-Amp supply current sensing technique
Book review: 'Young and Defiant in Tehran' by Shahram Khosravi
No full textThis book review discusses 'Young and Defiant in Tehran' by Shahram Khosravi
Dual input all-pass filter using DVCC
No full textMinaei, Shahram (Dogus Author) -- Conference full title: International Symposium on Signals, Circuits and Systems, SCS 2003; Iasi; Romania; 10 July 2003 through 11 July 2003.A new first-order dual-input all-pass filter in current-mode operation using the differential voltage current conveyor (DVCC) is proposed. The novelty of the configuration is that the DVCC supplies high input impedances for applications requesting differential or floating inputs. PSPICE simulation results verifying theoretical analyses are also included
General configuration for realizing current-mode first-order all-pass filter using DVCC
No full textMinaei, Shahram (Dogus Author)In this paper, a new general configuration for realizing current-mode all-pass filter circuits using differential voltage current conveyor (DVCC) is proposed. The proposed configuration is composed of a DVCC and five passive admittances. However, each of the circuits extracted from the proposed configuration uses only three passive elements. As an application, the proposed configuration is used to construct a quadrature oscillator. The theoretical results are verified by SPICE simulations
Universal current-mode filters and parasitic impedance effects on the filter performances
No full textMinaei, Shahram (Dogus Author)In this letter, two universal current-mode (CM) filters for simultaneously realizing low-pass, band-pass and high-pass characteristics are proposed. Both of the presented filters can also realize notch and all-pass responses with interconnection of the relevant output currents. They employ second-generation current-controlled conveyors (CCCIIs) and only grounded capacitors. They also have low active and passive element sensitivities along with electronically adjustable angular resonance frequency (omega(0)) and quality factor (Q). Based on the first developed filter, the parasitic impedance effects of the conveyors on the filter performances are investigated in detail. Simulation results using SPICE simulation program are included to verify the theory
Examination of contagion in financial markets in Iran Using a Combination of Ornstein Uhlenbeck Process and Continuous Wavelet Transform
No full textNowadays, with development of information system and interaction among financial markets across the world, downturn and boom transition in different markets is growing with a significant speed and with regard to developing economies in countries like Iran; contagion of crisis from global markets, slows down the development of the domestic economy. This study, by examine the contagion in financial markets of Iran and figure out, how the positive and negative shocks moves in different markets, tries to present guidelines for policy makers in order to improve domestic economy to avoid or control the entrance of shocks in national economic. The sample includes time series data of commodity prices on oil market, stock market of Tehran, foreign exchange market and gold market over a period of 8 years (Dec, 2008 –Dec, 2016) with weekly sampling rate. In order to achieve mentioned goals, we utilized a combination of Ornstein Uhlenbeck and Continuous Wavelet Transform. It finds out that the starting point of contagion in the financial markets of Iran is oil market and the speed of synchronization between stock market and oil market is more than other markets and then the foreign market and gold market are in the next places. In next step, it finds that the coherence of markets in short-run is powerfull between oil market and other markets, but this coherence in long-run is just between oil market with stock market and foreign exchange market, and after global oil sanction in 2012 against Iran, the coherrence between oil market with stock and foreign exchange markets is growed in middle-run
ASD: çok amaçlı ayarlanabilir sınıflandırıcı devreler
No full textGöknar, İzzet Cem (Dogus Author) -- Minaei, Shahram (Dogus Author) -- Yıldız, Merih (Dogus Author)Çalışmada, ayarlanabilir sınıflandırıcı devreleri ve uygulama alanları incelenmiştir. AMS 0.35 μm CMOS prosesi ile, tasarlanan sınıflandırıcı bir tümdevrenin üretimi de yapılmıştır. Bu sınıflandırıcı devresinin kontrol parametrelerinin bulunmasını sağlayan öğrenme algoritmaları çeşitli uygulamalar için geliştirilmiştir. Sınıflandırma işlemleri geliştirilen algoritmalar ve üretilen devre ile İris ve Haberman veri kümelerine uygulanarak sonuçların uyum içinde olduğu gösterilmiştir.TÜBİTA
Pulse width modulation using a recently developed CMOS core circuit
No full textGöknar, İzzet Cem (Dogus Author) -- Minaei, Shahram (Dogus Author) -- Yıldız, Merih (Dogus Author) -- Akçakaya, Ergül (Dogus Author)In this paper a new approach for a Pulse Width Modulation (PWM) circuit operating in current-mode using a CMOS classifier core circuit, and its application to level crossing are presented. The proposed architecture is much simpler than existing PWM methods and the generated PWM signal can be controlled electronically through the control currents of a core circuit. Measurements performed with DU-TCC 1209, an IC designed and manufactured using 0.35 μm AMS technology parameters, show a perfect match with theoretical results
Vient de paraître : Illegal' Traveller: An Auto-ethnography of Borders / Shahram Khosravi
No full textIllegal' Traveller: An Auto-ethnography of Borders / Shahram Khosravi, Basingstoke, Palgrave Macmillan, 2011. -(Global ethics series). - 160 p. Based on fieldwork among undocumented immigrants and asylum seekers,Illegal Traveller offers a narrative of the polysemic nature of borders, border politics, and rituals and performances of border-crossing. Interjecting personal experiences into ethnographic writing it is "a form of self-narrative that places the self within a social context." SHAHRAM..
- …
