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  1 - Increasing data throughput in HF channel by decision feedback equalizer employing MC-FQRD-RLS algorithm and weight extraction in data mode
  yahya ravaie Mohammad mahdinejadnouri mohammadhosein madani
  Increasing data throughput of Multipath time-varying HF channel by employing decision feedback equalization is addressed. In this paper, we propose multichannel FQRD-RLS adaptive filtering algorithm employing weight extraction in Decision-directed mode. A comparison bet More

  Increasing data throughput of Multipath time-varying HF channel by employing decision feedback equalization is addressed. In this paper, we propose multichannel FQRD-RLS adaptive filtering algorithm employing weight extraction in Decision-directed mode. A comparison between this technique and IQRD-RLS algorithm is performed. Simulation is conducted under channel parameters with respect to MIL-STD-188-110B. The results show higher data throughput in a frame with acceptable computational cost. It is also shown that the achieved data throughput is as same as using MC-FQRD-RLS algorithm in Full-Iteration equalization mode, at a much lower computational cost. Manuscript profile
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  2 - A Wideband Low-Noise Downconversion Mixerwith Positive-Negative Feedbacks
  Hadi Naderian Ahmad Hakimi
  10.7508/jist.2013.02.003
  This paper presents a wideband low-noise mixer in CMOS 0.13-um technology that operates between 2–10.5 GHz. The mixer has a Gilbert cell configuration that employs broadband low-noise trans conductors designed using the negative-positive feedback technique used in low-n More

  This paper presents a wideband low-noise mixer in CMOS 0.13-um technology that operates between 2–10.5 GHz. The mixer has a Gilbert cell configuration that employs broadband low-noise trans conductors designed using the negative-positive feedback technique used in low-noise amplifier designs. This method allows broadband input matching. The current-bleeding technique is also used so that a high conversion gain can be achieved. Simulation results show excellent noise and gain performance across the frequency span with an average double-sideband noise figure of 2.9 dB and a conversion gain of 15.5 dB. It has a third-order intermodulation intercept point of -8.7 dBm at 5 GHz. Manuscript profile
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  3 - Building and Managing the Constituencies: Requirements and Experiences
  Mohammadreza haeri Yazdi Bab Hadeston
  n this paper the challenges of managing several key constituencies are described. Examples of existing parks are used to illustrate the challenge and to show the problems that were faced and the approaches that were taken to overcome them. Foresight, or similar longer t More

  n this paper the challenges of managing several key constituencies are described. Examples of existing parks are used to illustrate the challenge and to show the problems that were faced and the approaches that were taken to overcome them. Foresight, or similar longer term visioning tools are proposed as a strategy to develop the shared vision necessary to sustain efforts over the medium to longer time period. The final section reviews key challenges facing parks with particular emphasis on: the advantages and disadvantages of fiscal incentives the role of regional hubs the widening range of tools that are needed alongside the S&T park to foster knowledgebased businesses the role and contributions that have been made by universities and how can these be expanded in future. Manuscript profile
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  4 - Design and Control of Three-Phase Shunt Active Power Filter Using the Sliding Mode Control and Energy Feedback
  M. Nayeripour A. Yazdian Varjani M. Mohamadian H. R. mohammadi
  The presence of nonlinear and unbalance loads in a three-phase network causes harmonics generation and dissipation in power network. One of the usual methods used for decreasing and eliminating these effects is the application of active and passive filter. The passive f More

  The presence of nonlinear and unbalance loads in a three-phase network causes harmonics generation and dissipation in power network. One of the usual methods used for decreasing and eliminating these effects is the application of active and passive filter. The passive filter is designed for a particular kind of frequency and therefore eliminates a particular harmonics. Its weakness, however, is the possibility of its resonance with the equivalent network impedance and the large size of its elements. The active filter helps to remove the above problems. Moreover, this filter causes the harmonics to be rejected individually or all together and prohibits the occurrence of resonance with the network. One of the problems of these filters is the limited dynamics response that considers the steady state of harmonics. In this paper, unlike the previous methods on single phase analysis, the inverter used in active filter is analyzed more precisely, i.e., the simultaneous three- phase analysis. The ohmic effect of phase-inductances is also taken into account. The inverter control system makes use of two internal and external loops. The external loop produces suitable signal for on/off switching through sliding mode control. The internal loop utilizes energy feedback to adjust the capacitor voltages. This new method effectively improves the speed of dynamic filter response in comparison with the previously reported methods and is able to quickly compensate harmonics and load unbalancing. Manuscript profile
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  5 - Design of a Low-Pass Switched Capacitor Fourth Order Chebyshev Filter Using an Improved Auto Zero Integrator
  Mohammad Rashtian O. Hashemipour K. Navi
  In this work the low-voltage high-speed auto zeroed integrator characteristics is improved by utilizing the non-linear properties of switches. Based on this improvement a newly designed structure for a low-pass filter is presented. The designed filter is a fourth order More

  In this work the low-voltage high-speed auto zeroed integrator characteristics is improved by utilizing the non-linear properties of switches. Based on this improvement a newly designed structure for a low-pass filter is presented. The designed filter is a fourth order Chebyshev with pass band frequency of 500 KHz and sampling frequency of 5 MHz. Based on this method a fast and accurate sample and hold structure is introduced. The designed work is simulated using 0.25µm CMOS technology at 1.2 V supply voltage. Manuscript profile
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  6 - Design and Simulation of a Two Stages OPAMP Using Positive Feedback for Achieving to a High Unity Gain Bandwidth and a High DC Gain
  P. Moallem A. Shiri Sichani
  The Fabrication of switch capacitor Filters and continuous time CMOS circuits, with a suitable unity gain bandwidth, a high DC gain and a high quality factor are a major challenge in integrated circuits design basically. This article is proposed a novel positive feedbac More

  The Fabrication of switch capacitor Filters and continuous time CMOS circuits, with a suitable unity gain bandwidth, a high DC gain and a high quality factor are a major challenge in integrated circuits design basically. This article is proposed a novel positive feedback topology for designing of OPAMP kernel and then a sample of OPAMP based on this method by tuning of the fabrication parameters is designed. The results of simulations which are done in frequency and time domain demonstrate that unity gain bandwidth of the designed OPAMP is greater than 1.4GHz and DC gain is greater than 108dB that in comparison with similar designs based on positive feedback can demonstrate there are plentiful increment in unity gain bandwidth and suitable increment in DC gain. The phase margin of the designed OPAMP is greater than 170 degree. Moreover, investigation of the proposed design outputs in time domain demonstrates the stability of the proposed OPAMP. Manuscript profile
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  7 - Power System Stability Improvement Using QFT-Based Excitation Robust Control
  A. Akbari Forod H. Seifi A. khaki sedigh
  Due to uncertainties in system modeling as well as system parameters, current excitation systems are unable to perform quite satisfactorily over a wide range of operating conditions. In this paper a QFT-based excitation robust control is proposed which the above mention More

  Due to uncertainties in system modeling as well as system parameters, current excitation systems are unable to perform quite satisfactorily over a wide range of operating conditions. In this paper a QFT-based excitation robust control is proposed which the above mentioned uncertainties are, somehow, considered. The Horowitz second method is employed in the design of the nonlinear QFT controller. Manuscript profile
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  8 - Designing an Optimal Proportional-Integral Sliding Surface for a Quarter Car Active Suspension System with Suspension Components Possessing Uncertain Constants and Nonlinear Characteristics
  S. A. Zahiripour A. A. Jalali
  In this paper, design of a controller for a quarter car active suspension system have been done with the focus on sliding mode strategy. Suspension components, including spring and shock-absorber have nonlinear characteristics with uncertain constants, but they have def More

  In this paper, design of a controller for a quarter car active suspension system have been done with the focus on sliding mode strategy. Suspension components, including spring and shock-absorber have nonlinear characteristics with uncertain constants, but they have defined bound. To simplify the controller designing, feedback-linearization is proposed, then with using the optimal strategy, we obtain a proportional - integral sliding surface and a controller for meeting the sliding condition has been proposed. The design process is in a such way that not only, guarantees asymptotic stability of the suspension system in the presence of parametric uncertainties, but also the designer can supply his slightly trade-off between convenience of passengers and controllability of car, with setting some parameters. Manuscript profile
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  9 - Content Based Image Retrieval by the Fusion of Short Term Learning Methods
  B. Bagheri M. Pourmahyabadi H. Nezamabadi-pour
  Content based image retrieval (CBIR) contains a set of techniques to process the visual features of a query image, in order to retrieve images semantically similar to it, in a database. To improve the performance of image retrieval systems, relevance feedback tool can b More

  Content based image retrieval (CBIR) contains a set of techniques to process the visual features of a query image, in order to retrieve images semantically similar to it, in a database. To improve the performance of image retrieval systems, relevance feedback tool can be used. In this research, to increase the effectiveness of the image retrieval systems, the fusion of two (multiple) short term learning methods based on relevance feedback is proposed. In the proposed method, fusion is performed in three levels: fusion in ranks, fusion in retrieved images, and fusion in similarities. To evaluate the performance of the proposed method, a CBIR system with 10000 images of 82 different semantic groups is employed. The experimental results confirm the superior of suggested method in terms of retrieval precision. Manuscript profile
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  10 - Content Based Image Retrieval by the Fusion of Short Term Learning Methods
  B. Bagheri M. Pourmahyabadi H. Nezamabadi-pour
  Content based image retrieval (CBIR) contains a set of techniques to process the visual features of a query image, in order to retrieve images semantically similar to it, in a database. To improve the performance of image retrieval systems, relevance feedback tool can b More

  Content based image retrieval (CBIR) contains a set of techniques to process the visual features of a query image, in order to retrieve images semantically similar to it, in a database. To improve the performance of image retrieval systems, relevance feedback tool can be used. In this research, to increase the effectiveness of the image retrieval systems, the fusion of two (multiple) short term learning methods based on relevance feedback is proposed. In the proposed method, fusion is performed in three levels: fusion in ranks, fusion in retrieved images, and fusion in similarities. To evaluate the performance of the proposed method, a CBIR system with 10000 images of 82 different semantic groups is employed. The experimental results confirm the superior of suggested method in terms of retrieval precision. Manuscript profile
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  11 - Designing Excellence Management Model in the Cement Industry Using Human Capital Approach
  morteza hashempour      
  The purpose of this article is designing excellence management model in the Cement industry using human capital approach. It is a practical research using Exploratory mixed method (Cross-sectional survey and Delphi by type of study). The population of this research is a More

  The purpose of this article is designing excellence management model in the Cement industry using human capital approach. It is a practical research using Exploratory mixed method (Cross-sectional survey and Delphi by type of study). The population of this research is all Specialists and experts in the field of cement industry that are 1000 persons and 255 samples selected by using simple random sampling method and Table Bula to respond 216 researcher-made indices. Also 80 educated and experienced people in the Cement industry with managerial insight were selected to investigate their opinion, dimensions, components and indicators using confirmatory factor analysis. The construct validity and Cronbach's alpha obtained (٧٨ percent) indicates the validity and reliability of the questionnaire. Exploratory factor analysis indicates 4 dimensions (Data, process, output and feedback) and 12 components that explained 72.45 percent of variance. Also Confirmatory factor analysis indicated that the model was a good fit and confirmed dimensions and components of human capital management model with human capital approach. In qualitative section, dimensions, components and criteria of excellence management model confirmed by delphi (with three posts) and Brainstorming among 30 experts in this field (focus ring) too. Manuscript profile