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Article
Publication date: 9 November 2012

Redha Benachour, Saïda Latreche, Mohamed El Hadi Latreche and Christian Gontrand

The present work aims to explain how the nonlinear average model can be used in power electronic integration design as a behavioral model.

Abstract

Purpose

The present work aims to explain how the nonlinear average model can be used in power electronic integration design as a behavioral model.

Design/methodology/approach

The nonlinear average model is used in power electronic integration design as a behavioral model, where it is applied to a voltage source inverter based on IGBTs. This model was chosen because it takes into account the nonlinearity of the power semiconductor components and the wiring circuit effects, which can be formalized by the virtual delay concept. In addition, the nonlinear average model cannot distinguish between slow and quick variables and this is an important feature of the model convergence.

Findings

The paper studies extensively the construction of the nonlinear average model algorithm theoretically. Detailed explanations of the application of this model to voltage source inverter design are provided. The study demonstrates how this model illustrates the effect of the nonlinearity of the power semiconductor components' characteristics on dynamic electrical quantities. It also predicts the effects due to wiring in the inverter circuit.

Research limitations/implications

More simulations and experimental analysis are still necessary to improve the model's accuracy, by using other static characteristic approaches, and to validate the applicability of the model to different converter topologies.

Practical implications

The paper formulates a simple nonlinear average model algorithm, discussing each step. This model was described by VHDL‐AMS. On the one hand, it will assist theoretical and practical research on different topologies of power electronic converters, particularly in power integration systems design such as the integrated power electronics modules (IPEM). On the other hand, it will give designers a more precise behavioral model with a simpler design process.

Originality/value

The nonlinear average model used in power electronic integration design as behavioral model is a novel approach. This model reduces computational costs significantly, takes physical effects into account and is easy to implement.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Abstract

Details

Transportation and Traffic Theory in the 21st Century
Type: Book
ISBN: 978-0-080-43926-6

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Article
Publication date: 8 May 2007

Yushing Cheung and Jae H. Chung

This paper aims to make an industrial robot intelligently and remotely cooperate with humans to work in unknown unstructured environments.

Abstract

Purpose

This paper aims to make an industrial robot intelligently and remotely cooperate with humans to work in unknown unstructured environments.

Design/methodology/approach

Presents a bilateral adaptive teleoperation control approach involving a contact force driven compensation with an auto‐switching function, which utilizes a biologically motivated compliance function. Based on sensed contact force, the switching function can adjust its slave control input to decide how much robotic intelligences should intervene in the system by switching modes. Other schemes for robotic intelligence, robotic impedances and compensators, are investigated to guarantee good transparency without warranting human error and maintain a stable contact, based on the force feedback, in constrained motion while a communication delay exists.

Findings

The simulation and experimental results demonstrate transparency and contact stability in the presence of constant and time‐varying communication delays, respectively. The proposed bilateral adaptive teleoperation control method outperforms three other techniques.

Originality/value

This paper introduces an adaptive teleoperation control method with local robotic intelligence assistance. The developed method does not modify the existing designs of industrial robots. The contact force and position and force errors are well controlled to obtain a stable contact and transparency, through adaptation of robotic impedances.

Details

Industrial Robot: An International Journal, vol. 34 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 11 May 2015

Bikramaditya Das, Bidyadhar Subudhi and Bibhuti Bhusan Pati

The purpose of this paper is to propose development of a formation control algorithm by employing a nonlinear observer for compensating the delay in the sensor signal…

Abstract

Purpose

The purpose of this paper is to propose development of a formation control algorithm by employing a nonlinear observer for compensating the delay in the sensor signal transmission to the controller arising due to packet dropout in acoustic medium.

Design/methodology/approach

A robust control law is developed using the sliding mode approach integrated with a communication consensus algorithm for achieving cooperative motion of acoustic underwater vehicles in a group ensuring the transfer of information among the AUVs. In acoustic medium, inter-vehicle communication is challenging for a group of AUVs deployed in formation because underwater channel encounter a number of constraints such as low data rate, packet delays and dropouts.

Findings

It is observed that the sliding mode control-unscented Kalman filter formation control exhibits superior control performance such as mitigating larger initial error of estimation and removing the use of the Jacobian matrices among the three controllers developed. The proposed nonlinear observer estimates the un-measureable states such as position in x, y and z-axes, heading, rudder and sturn angle, needed for generating the formation control. A simulation setup is realized to demonstrate the performance of the proposed observer-based formation controller. Simulations were performed in MATLAB and the obtained results are analysed and compared which envisage that the proposed control algorithm provides efficient formation control under the acoustic communication constraints.

Originality/value

Development of observer for achieving formation control of AUVs in underwater area – common reference velocity and error signals being available to all cooperating AUVs – UKO performs better based on initial error estimation and tracking the same path in shallow water area.

Details

International Journal of Intelligent Unmanned Systems, vol. 3 no. 2/3
Type: Research Article
ISSN: 2049-6427

Keywords

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Article
Publication date: 1 February 1988

Larry L. Learn

This article provides a broad overview of telecommunications and network‐related technologies. Topics covered include identification and review of network elements, analog…

Abstract

This article provides a broad overview of telecommunications and network‐related technologies. Topics covered include identification and review of network elements, analog and digital signals, synchronous and asynchronous transmission formats, transmission media and equipment, transmission techniques and characteristics, multiplexing, network types, access technologies, network architectures and topologies, local‐area network technologies and attributes, protocols and protocol issues, gateways, internetworking, local networking alternatives, equipment certification, and various aspects of network management. It is intended to provide the practicing professional in the field of library and information science with a broad, up‐to‐date technical review that might serve to support and facilitate further investigation of current developments in networks and networking. Although the broad range of topics is not treated in depth, numerous references are provided for further investigation.

Details

Library Hi Tech, vol. 6 no. 2
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 31 December 2006

Yu Wang and Jie Wu

Compared to the traditional wireless network, the multi‐hop ad hoc wireless network is self‐configurable, dynamic, and distributed. During the past few years, many routing…

Abstract

Compared to the traditional wireless network, the multi‐hop ad hoc wireless network is self‐configurable, dynamic, and distributed. During the past few years, many routing protocols have been proposed for this particular network environment. While in wired and optical networks, multi‐protocol label switching (MPLS) has clearly shown its advantages in routing and switching such as flexibility, high efficiency, scalability, and low cost. However MPLS is complex and does not consider the mobility issue for wireless networks, especially for ad hoc wireless networks. This paper migrates the label concept into the ad hoc network and provides a framework for the efficient label routing protocol(LRP) in such a network. The MAC layer is also optimized with LRP for shorter delay, power saving, and higher efficiency. The simulation results show that the delay is improved significantly with this cross‐layer routing protocol.

Details

International Journal of Pervasive Computing and Communications, vol. 2 no. 4
Type: Research Article
ISSN: 1742-7371

Keywords

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Article
Publication date: 1 May 2006

Brian P. DeJong, Eric L. Faulring, J. Edward Colgate, Michael A. Peshkin, Hyosig Kang, Young S. Park and Thomas F. Ewing

Sets out to discuss lessons learned from the creation and use of an over‐the‐internet teleoperation testbed.

Abstract

Purpose

Sets out to discuss lessons learned from the creation and use of an over‐the‐internet teleoperation testbed.

Design/methodology/approach

Seven lessons learned from the testbed are presented.

Findings

This teleoperation interface improves task performance, as proved by a single demonstration.

Originality/value

In helping to overcome time‐delay difficulties in the operation, leading to dramatically improved task performance, this study contributes significantly to the improvement of teleoperation by making better use of human skills.

Details

Industrial Robot: An International Journal, vol. 33 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

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Book part
Publication date: 12 September 1997

Carlos F. Daganzo

Abstract

Details

Fundamentals of Transportation and Traffic Operations
Type: Book
ISBN: 978-0-08-042785-0

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Article
Publication date: 1 February 1988

Dennis G. Perry, Steven H. Blumenthal and Robert M. Hinden

The ARPANET, initiated in 1969 by the Advanced Research Projects Agency (DARPA) of the Department of Defense (DoD), was the first wide area packet switching network. In…

Abstract

The ARPANET, initiated in 1969 by the Advanced Research Projects Agency (DARPA) of the Department of Defense (DoD), was the first wide area packet switching network. In 1984, the ARPANET, which had grown to over 100 nodes, was separated into two parts: an operational component, the MILNET, to serve the operational needs of the DoD, and a research component that retained the ARPANET name. After the network split, the MILNET expanded, and it should reach over 250 nodes within a year. The DARPA Internet was formed in the 1970s in response to a requirement to interconnect different types of packet‐switching networks that were being implemented. It has grown to be very large; it now consists of over 330 networks, hundreds of gateways, and tens of thousands of hosts. Where the ARPANET used to connect hosts that were single computers into a network, many of these hosts now serve as gateways to local campus networks, regional networks, and other national networks, such as the NSFNET. The impact of this growing system of inter‐connected networks on research, communications, and library access will be profound.

Details

Library Hi Tech, vol. 6 no. 2
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 1 January 1997

Granted that the Information Superhighway is here, what are the nine imperative issues arising from the explosion of content? was the question we discussed in Chapter 6…

Abstract

Granted that the Information Superhighway is here, what are the nine imperative issues arising from the explosion of content? was the question we discussed in Chapter 6. Bill Gates puts the date of the Information Superskyway (as we prefer to call it) at least a decade away; and Michael Dertouzos, Director of MIT Computer Science Laboratory since 1974, deplores the decade that will be wasted. What are the Technology, Demand, and Supply Issues that drive/delay the Highway/Sky‐way? Technology Issue 1: Hardly anybody is working on Shared Conventions for interconnected machines to work together. Dertouzos warns: Major players of the 1990s who keep extolling fiber optics, real‐time video, virtual reality, multimedia, and electronic commerce will discover that none of these awesome stuff will be useful unless computers and software at diverse sites can “understand” one another. Supply Issue 1: Dertouzos' war of spiders is one in which 3C industry members each offer the customer a car to drive on the Highway so long as he(she) never drives another car or wheeled vehicle. Supply Issue 2: Dertouzos declares: “There is no true information infrastructure anywhere in the world today.” Everybody is busy putting up toll booths, but nobody is putting up the highway. Demand Issue 1: Europeans declare “Good roads create traffic.” Video on demand is too small to justify the massive investment necessary to connect just the US homes to the broadband network. Europeans urge the Economic Community to remove IT barriers. Demand Issue 2: American and European experts concur that customer and business applications are the driver. This concurrent emphasis on applications confirms the USE‐orientation: What do you USE the high‐speed, high‐capacity switched network for? which we raised as Issue 1 in Chapter 6. Demand Issue 3: In his keynote address to the Harvard Conference on Internet and Society, Intel Vice President McGeady blasted Digital Pundits (Al Gore, Nicholas Negroponte) for taking us down the wrong path of interactive television which would simply subject us to an avalanche of advertising… They all failed to realize that the information reformation is about personal information, not about the same old stuff turned into bits and delivered to your doorstep in a slightly new way. It's about creating on one's own. Technology Issue 2: Technologically, what is the promise; what is the bottleneck? Combining the advantages of two technologies ‐ optics and semiconductors ‐ holds the best promise of reliable, fast, and inexpensive storage and transfer, communication and computing.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 9 no. 1/2
Type: Research Article
ISSN: 1355-5855

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