The Population Growth, Land-use Development and the Increase in Vehicle Ownership in big cities have caused an increase in Travel Demand and the volume of vehicles passing through Urban Routes. Travel Time in the urba...
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ISBN:
(纸本)9789806560680
The Population Growth, Land-use Development and the Increase in Vehicle Ownership in big cities have caused an increase in Travel Demand and the volume of vehicles passing through Urban Routes. Travel Time in the urban route network due to increase in congestion in one of the most important problems in Metropolises. A considerable part of Travel Time in the Metropolitan routes network is related to delay time in intersections. Thus, controlling methods for intersections in order to decrease such delays is of a great importance. The application of Fuzzy Logic as a control basis in engineering issues has a proper background. In this study, a method for controlling such signalized intersections has been assessed and proposed using Fuzzy Method. Various Experiments in simulated environments has shown that as for different traffic conditions, this algorithm could considerably be better than the conventional pre-time control algorithms and actuated ones.
Ultrasonic dental scalers are electronically powered dental cleaning tools which are commonly used by clinicians for dental cleaning. They were developed in the mid 1950s [S.C. Trenter, A.D. Walmsley, G. Landini, J.M....
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Ultrasonic dental scalers are electronically powered dental cleaning tools which are commonly used by clinicians for dental cleaning. They were developed in the mid 1950s [S.C. Trenter, A.D. Walmsley, G. Landini, J.M. Shippen, Assessment of the ultrasonic dental scaler insert, Med. Eng. Phy. 24 (2002) 139-144]. Ultrasonic scalers are being widely used with few studies on the correct methods and techniques that should be used to obtain their maximum efficiency. Different types of inserts/tips do not show clearly which particular designs are best suited to the task of removing dental calculus to combat periodontal disease. The aim of this study is to begin preliminary investigation on whether the performance of these clinical instruments may be improved if the displacement waveform of the scaler tip could be controlled. (c) 2005 Elsevier B.V. All rights reserved.
IRMCF343 is designed to achieve low cost and high performance one chip solution for digital PFC and PMSM with sensorless control. This paper introduces the digital PFC control algorithm of the chip in detail, designs ...
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IRMCF343 is designed to achieve low cost and high performance one chip solution for digital PFC and PMSM with sensorless control. This paper introduces the digital PFC control algorithm of the chip in detail, designs a novel, bridgeless PFC topology which has simple current sensing circuit and low EMI, and compares bridge-less PFC and conventional Boost PFC circuits. Experimental results verify that the bridgeless PFC has higher power factor and efficiency comparing with conventional Boost PFC. When the designed bridgeless PFC circuit's power is 1 000 W, the power factor is more than 0.98, the THD is less than 10%, the efficiency is more than 0.97, and the EMI test result is lower than standard.
The response of Metal Oxide Chemical sensors is highly sensitive to operating temperature, and it is well known that this temperature has to be controlled within few degrees. Moreover operating sensors with variable t...
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ISBN:
(纸本)9780780393592
The response of Metal Oxide Chemical sensors is highly sensitive to operating temperature, and it is well known that this temperature has to be controlled within few degrees. Moreover operating sensors with variable temperature allows enhancing chemical sensing system capabilities. In this paper a simple but highly flexible temperature control system for Metal Oxide conductive chemical sensors is presented and discussed.
Iterative modeling and simulation form an integral part of modern control system design. While industry engineers rely heavily on proprietary "legacy" models to rapidly develop and implement new control syst...
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ISBN:
(纸本)9781424401581
Iterative modeling and simulation form an integral part of modern control system design. While industry engineers rely heavily on proprietary "legacy" models to rapidly develop and implement new control systems, others must initiate models to develop production-capable control systems. The design process has now been considerably improved by the availability of COTS modeling packages, vehicle simulators, software environments for RT execution and compatible production hardware. This paper documents the incremental approach adopted by the Mississippi State University Challenge X team to configure the overall powertrain system controller of its through-the-road parallel hybrid electric vehicle.
This paper presents control algorithm for dynamic voltage restorer (DVR) to improve voltage quality problems such as voltage sags/swells in distribution systems. When voltage sags/swells occur, possibly, due to faults...
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ISBN:
(纸本)9781424401109
This paper presents control algorithm for dynamic voltage restorer (DVR) to improve voltage quality problems such as voltage sags/swells in distribution systems. When voltage sags/swells occur, possibly, due to faults and some load switching, DVR has to detect the problem and inject appropriate voltage component as soon as possible. The paper proposes a dynamic control based on feedforward and feedback control. The proposed control enhances the performance of DVR. In the proposed control, voltage and current closed-loop controllers are considered. A simple distribution system with sensitive load and DVR at 22 kV is used to test the proposed control algorithm. The simulation results show that the proposed control given a better voltage quality and enhances the performance of DVR.
The effective optimal and practical time-dependent heat transfer coefficients of the cooling passage for highspeed motors are determined in a three-dimensional optimal control problem. The control algorithm utilizing ...
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The effective optimal and practical time-dependent heat transfer coefficients of the cooling passage for highspeed motors are determined in a three-dimensional optimal control problem. The control algorithm utilizing the steepest descent method and a general purpose commercial code CFX4.4 is applied successfully in accordance with the design (or desired) temperature distributions on the interior heating surface. Two different design temperature distributions are used to illustrate the validity of determining both the effective optimal and practical heat transfer coefficients. Results of the numerical simulation show that the reliable estimated effective practical heat transfer coefficients can be obtained by using the present optimal inverse design (or optimal control) algorithm.
Electronic attack on air defense radar networks by electronic combat air vehicles (ECAVs) is considered. The scope of the attack is the creation of a coherent phantom track in two dimensions-range and azimuth-by a tea...
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Electronic attack on air defense radar networks by electronic combat air vehicles (ECAVs) is considered. The scope of the attack is the creation of a coherent phantom track in two dimensions-range and azimuth-by a team of cooperatively controlled ECAVs, each capable of intercepting and sending delayed returns of radar pulses. It is first shown that assuming constant speeds for the phantom track and ECAVs severely restricts where the ECAVs can fly. Accordingly, general dynamic and spatial limitations on an ECAV are developed given ranges on the ECAV speed, phantom track speed, and ECAV region of antenna operation;six dynamical systems are also constructed for simulating feasible ECAV trajectories to test the analytical limitations. This theory is applied to construct detailed flyable ranges for an ECAV generating a straight and a circular phantom track, separately. Based on distilling the results, generalized bounds are presented-independent of the phantom track type-for the initial conditions and time-dependent flyable ranges of a team of ECAVs. These bounds are then used with coordination functions to informally solve an illustrative decentralized cooperative control problem in which the ECAV team seeks an optimal straight phantom track to minimize their bounds-dependent aggregate cost.
Background The last two decades have witnessed unprecedented technological progress in the development of continuous glucose sensors, resulting in the first generation of commercial glucose monitors. This has fuelled ...
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Background The last two decades have witnessed unprecedented technological progress in the development of continuous glucose sensors, resulting in the first generation of commercial glucose monitors. This has fuelled the development of prototypes of a closed-loop system based on the combination of a continuous monitor, a control algorithm, and an insulin pump. Method A review of electromechanical closed-loop approaches is presented. This is followed by a review of existing prototypes and associated glucose sensors. A literature review was undertaken from 1960 to 2004. Results Two main approaches exist. The extracorporeal s.c.-s.c. approach employs subcutaneous glucose monitoring and subcutaneous insulin delivery. The implantable i.v.-i.p. approach adopts intravenous sampling and intraperitoneal insulin delivery. Feasibility of both solutions has been demonstrated in small-scale laboratory studies using either the classical proportional-integral-derivative controller or a model predictive controller. Performance in the home setting has yet to be demonstrated. Conclusions The glucose monitor remains the main limiting factor in the development of a commercially viable closed-loop system, as presently available monitors fail to demonstrate satisfactory characteristics in terms of reliability and/or accuracy. Regulatory issues are the second limiting factor. Closed-loop systems are likely to be used first by health-care professionals in controlled environments such as intensive care units.
Canal automation equipment in the East Bench Irrigation District in Dillon, Montana, was over 30 years old and needed to be replaced. Portions of the old automation system were salvaged in an attempt to reduce rehabil...
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Canal automation equipment in the East Bench Irrigation District in Dillon, Montana, was over 30 years old and needed to be replaced. Portions of the old automation system were salvaged in an attempt to reduce rehabilitation costs. Because wiring diagrams were not available for the old control system, time would have been saved if the old control system were completely removed and replaced with a completely new system. Data communication via radio and bubbler water level sensors proved to be troublesome. After three seasons of operation, problems with the new automation system were corrected, but it became evident that a technician was needed to maintain the system. Copyright (C) 2006 John Wiley & Sons, Ltd.
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