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This paper describes the development of a power device characterization curve tracer based on transient thermal measurement. Experimental test set ups along with the required conditions to mitigate the measurement errors are discussed. The measurement algorithms are implemented in LabVIEW environment as a set up controller. The junction temperature is maintained at the specified set point for carrying...
The infrared imaging technology is widely used in nondestructive and noninvasive imaging nowadays. The scientists and researches are showing much more interest to the expansion of this technology in medical imaging. The infrared images show a passive relationship between the body surface temperature and tissue metabolism. Determination of the metabolism rate, hyperactive region and depth from the...
Most of the reported control algorithms for uninterruptible power supplies use either inductor currents or capacitor currents of their filter as feedback variables to regulate the output voltage. This paper proposes a simple non linear control using current and voltage of a DC/AC inverter of an isolated three phase power network. Theoretical analysis and simulation results demonstrate fast response,...
This paper presents the strategy of combining antenna selection with an adaptive modulation scheme for Multiple Output (MIMO) systems. The proposed scheme maximized the Average Spectral Efficincy (ASE) with a constant power for a given Bit Rate (BER) Constraint. This system provided the advantages of both antenna selection and adaptive modulation technique Also due to the practical system cannot estimates...
This paper presents the strategy of combining antenna selection with an adaptive modulation scheme for Multiple Input Multiple Output (MIMO) systems. The proposed scheme maximized the Average Spectral Efficiency (ASE) with a constant power for a given Bit Error Rate (BER) constraint. This system provided the advantages of both antenna selection and adaptive modulation technique Also due to the practical...
Antenna selection is an attractive technique in MIMO system that improves the system performance and reduces the system complexity and cost. Throughput based antenna selection is new. This technique utilizes cross layer information to select k instead of M transmit antennas to maximize the throughput of the system. Throughput based transmit antenna selection is proposed in this paper when truncated...
We present a systematic approach for design of extremum seeking (ES) controllers for a class of uncertain plants that are parameterized with unknown parameters. First, we present results for static plants and show how it is possible to combine, under certain general conditions, an arbitrary optimization method with an arbitrary parameter estimation method in order to obtain extremum seeking. Our main...
Considering the quality-of-service (QoS), power allocation is a critical importance issue in realizing multi-hop relay systems. In this paper considering the QoS Constraints in term of BER or instantaneous SNR, an optimal power allocation scheme that minimized the total power consumption in an amplify-and-forward (AF) multi-hop multi-branch transmission system is proposed. Considering an asymptotic...
Most electron sources are used to create a single beam. For high resolution instruments such as electron microscopes and electron lithography machines, most of the current that is emitted by the source is cut away by apertures. The typical emission current from a CRT (Cathode Ray Tube) impregnated tungsten source is hundreds of milli-amperes and from a Schottky source (field assisted emission from...
This study investigates the effect of converter slag- a by-product of steel industry- as an iron fertilizer on Fe and pH of some calcareous soils. Slag used contained approximately 24% of iron oxides plus a relatively large amount of calcium, silicon, phosphorus, and manganese. An incubation study was conducted with 3 calcareous soils for up to 2 months and the treatments included various amounts...
This study was carried out to study effects of super absorbent polymer and plant growth promoting rhizobacteria (PGPR) on yield and some physiological traits of maize (double cross 370) in Karaj region/Iran in 2009. Experiment was conducted as a randomized complete block design with 4 replicates and in two separate experiments under drought stress and normal conditions. Seven different treatments...
Ilseed crops have become a major industry in Golestan, Iran. However, these crops are not grown without risk. Proper management tools are essential to minimize potential risks and ensure maximum profits for farmers. This study aims to determine canola losses in harvest operations with three types of head. Losses of canola seeds occur in each level of canola production especially in harvesting level...
The main purpose of the paper is to present sophisticated means to implement Q-guidance scheme in satellite injection missions. Optimality and simplicity of Q-guidance approach makes it appropriate for practical settings of a wide range of launch systems. Calculation of required velocity as a fundamental and inherent concept of Q-guidance implementation for orbital injection missions has been proposed...
An infrared (IR) thermography measurement setup to capture the temperature distribution and power dissipation of the device under test is proposed in this paper. The system is based on a transparent oil heatsink which captures the thermal profile and run-time power dissipation from the device under test with a very fine degree of granularity. The proposed setup is used to perform the thermal analysis...
Optimal power allocation is a critical approach to realize the full potentials of relay-assisted transmission promised by the recent information-theoretic results. In this paper an optimal power allocation scheme that maximizes the instantaneous signal-to-noise ratio (SNR) in an amplify-an-forward (AF) multi-hop multi-branch transmission system is proposed. By considering an asymptotic expression...
In this paper, a novel analytic method is proposed for calculating the transfer function of an RF feedforward linearizer circuitry considering imbalances in the two loops of the circuit. Using Taylor series with complex coefficients in RF amplifier modelling, both AM-AM and AM-PM distortions are considered. Finally, the function of output envelope versus input envelope is achieved. Simulations results...
A new current mirror based all-pass, tunable phase shifting technique is proposed and simulated in 0.18 um CMOS, after a brief introduction on phase shifter applications, and comparison between different implementation methods. In the new current-mode approach, cut-off frequency of transistor is the operational limit of the proposed phase-shifter architecture and power consumption for this design...
The paper proposes a near-optimal, distributed implementation of the particle filter for large scale dynamical systems with sparse measurements, as in wireless sensor networks (WSN) and power distribution systems. Compared to the centralized approach, the distributed implementation of the particle filter is computationally efficient and provides considerable transmission bandwidth savings due to a...
The optimization algorithms which are inspired from intelligent behavior of honey bees are among the most recently introduced techniques. In this paper, a novel algorithm called bee swarm optimization, or BSO, is presented. The BSO is a population based optimization technique which is inspired from foraging behavior of honey bees. The proposed approach provides different patterns which are used by...
A new current mirror based all-pass, tunable phase shifter architecture is proposed in 0.18 um CMOS, after a brief introduction on phase shifter applications, and comparison between different implementation methods. In the new current-mode approach the cut-off frequency of transistor is the operational limit of the proposed phase-shifter architecture and power consumption for this design is 80 microwatts...
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