Digital Commons Network^™

Asymptotic Stability Of Nonholonomic Mobile Robot Formations Using Multilayer Neural Networks, Jagannathan Sarangapani, Travis Alan Dierks

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a combined kinematic/torque control law is developed for leader-follower based formation control using backstepping in order to accommodate the dynamics of the robots and the formation in contrast with kinematic-based formation controllers that are widely reported in the literature. A multilayer neural network (NN) is introduced along with robust integral of the sign of the error (RISE) feedback to approximate the dynamics of the follower as well as its leader using online weight tuning. It is shown using Lyapunov theory that the errors for the entire formation are asymptotically stable and the NN weights are bounded as …

A Normalized Fractionally Lower-Order Moment Algorithm For Space-Time Adaptive Processing, Y. Rosa Zheng, Genshe Chen, Erik Blasch

Electrical and Computer Engineering Faculty Research & Creative Works

A new space-time adaptive processing algorithm is proposed for clutter suppression in phased array radar systems. In contrast to the commonly used normalized least mean square (NLMS) algorithm which uses the second order moments of the data for adaptation, the proposed method uses the lower order moments of the data to adapt the weight coefficients. The normalization is also performed based on the data sample dispersion rather than the variance. Processing results using simulated and measured data show that the proposed algorithm converges faster than the NLMS algorithms in Gaussian and non-Gaussian clutter environments. It also provides better clutter suppression …

Channel Estimation And Phase-Correction For Robust Underwater Acoustic Communications, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a new channel estimation, equalization, and phase correction scheme to combat the convergence and stability problem encountered by time-domain adaptive equalizers in underwater acoustic communication systems. Large Doppler spread and symbol scaling in underwater channels have been challenging problems causing significant phase drift and performance degradation. Our new method targets this problem by first allowing phase errors in the estimation of the fading channel coefficients and then perform group-wise (rather than symbol-wise) phase estimation and correction after equalization and multiple channel combining. Single transmitter and multiple receiver data obtained through ocean experiments have been processed using the …

Asia Pacific Perspectives Vol. 7 No. 1, July 2007, University Of San Francisco, University Of San Francisco

Asia Pacific Perspectives

Contents:

Editor's Introduction by Joaquin L. Gonzalez III

Cross-Regional Trade Cooperation: The Mexico-Japan Free Trade Agreement by Sarita D. Jackson

Latin American and Asia-Pacific countries are fervently forging economic cooperative relationships, which began with the Asia-Pacific Economic Cooperation in 1989. The two regions have shifted away from looking intra-regionally for economic stability against the forces of globalization. Rather, they have moved towards emphasizing cross-regional trade pacts. Cross-regional trade pacts present a number of advantages for member countries. The Mexico-Japan FTA, as a case study, shows us that trade and FDI between member countries increase with cross-regional free trade agreements (FTA). …

A Growth Theory Perspective On The International Diffusion Of Electronic Commerce., S.C Ho, Robert John Kauffman, T.P. Liang

Research Collection School Of Computing and Information Systems

Information and communication technologies (ICTs) continue to have a profound effect on the economies and societies where they are used. In this article, we propose three related theories to describe the underlying mechanism for growth in e-commerce revenues at the national level. Endogenous growth theory posits that the primary drivers of e-commerce growth are internal to a country. Exogenous growth theory suggests that the primary drivers of e-commerce growth are external to an economic system, and reflect the forces of the regional economy. A blend of these, a mixed endogenous–exogenous growth theory, incorporates drivers from both the economy and …

A Comparison Of Print Advertisements From Egypt, Lebanon, Kuwait, Saudi Arabia, United Arab Emirates And The United States, Gilberto De Los Santos, Caroline Fisher, Salma Ghanem, Morris Kalliny, Anshu Saran

Business and Information Technology Faculty Research & Creative Works

This study examines cultural differences between the United States and the Arab world regarding low/high context, collectivism/individualism, time orientation and man's relationship with nature in print advertising. Study reveals that the main differences between the United States and the Arab world include cultural values that are embedded in religious values and beliefs.

Cultural Values Reflected In Arab And American Television Advertising, Morris Kalliny, Lance Gentry

Business and Information Technology Faculty Research & Creative Works

This study examines cultural values as reflected in U.S. And the Arab world television advertising. A total of 866 television commercials from Egypt, Kuwait, Lebanon, Saudi Arabia, United Arab Emirates and the United States were analyzed. Contrary to the common notion that the U.S. culture and the Arabic culture are vastly different, we found many similarities between the two cultures regarding TV advertising content and appeal. The findings contribute to the debate of standardization versus adaptation of international advertising.

Civil Control Of The Military And Police In Ireland: The Armed Forces, Tom Clonan

Books/Book chapters

Independence and Civil War: Origins of Irish Defence Forces The Irish armed forces, known as the Permanent Defence Forces (PDF) or ‘Oglaigh na hEireann’ number approximately 10,000 personnel across the Naval Service, Army and Air Corps. The Defence Forces in Ireland play an active role domestically in ‘Aid to the Civil Power’ Operations or ATCP Ops with the Irish police force, An Garda Siochana. The Defence Forces are also active internationally in UN peacekeeping and peace enforcement operations in Europe, Asia, Africa and the Middle East. As an organisation, the Irish Defence Forces is a direct descendant of the Irish …

Civil Control Of The Military And Police In Ireland: The Armed Forces, Tom Clonan

Books/Book chapters

The Irish armed forces, known as the Permanent Defence Forces (PDF) or ‘Oglaigh na hEireann’ number approximately 10,000 personnel across the Naval Service, Army and Air Corps. The Defence Forces in Ireland play an active role domestically in ‘Aid to the Civil Power’ Operations or ATCP Ops with the Irish police force, An Garda Siochana. The Defence Forces are also active internationally in UN peacekeeping and peace enforcement operations in Europe, Asia, Africa and the Middle East. As an organisation, the Irish Defence Forces is a direct descendant of the Irish Free State Army - initially formed in 1922 following …

Good Things Come In Small Packages: Tiny Plankton Producing Oxygen Near Dead Zone, Abbie Basile

Libraries Faculty & Staff Publications

(First paragraph) For many, the words “Lake Erie” bring to mind large things: big sport fish, sprawling waterfront homes, and an enormous body of water bordering four states and two countries. Similarly, much of the Lake Erie research of which the public is aware deals with larger biological organisms—larger algae and zooplankton, the small fish that eat the zooplankton, and the large fish that feed on those smaller fish. Over the years, the smaller lake life have been somewhat overlooked.

The Practitioner, The Priest, And The Professor: Perspectives On Self-Initiation In The American Neopagan Community, Marty Laubach, Louis Martinie’, Roselinda Clemons

Sociology and Anthropology Faculty Research

Initiation is a religious practice that is generally understood as involving socialization and acceptance into a religious community, but American Neopaganism, with its emphasis on individualism and autonomy, has evolved a meaning that challenges that simple understanding. American Neopagan communities are marketplaces of ideas that are comprised of groups and solo practitioners, all in interaction in which they might conduct main holidays together, but not necessarily work together in what they would consider more “serious” practices in which they receive the spirit communications with which they develop the ideas. Among groups, these practices include initiations through which candidates are trained …

Citax: Defining Xml Standards For Data Exchange In The Construction Industry Supply Chain, Alan V. Hore, Roger West

Conference papers

The current methods of ordering, delivering and invoicing of products in the construction industry is enormously inefficient, with vast quantities of paperwork, duplication of effort, scanning, re-keying and resolving mismatches between invoices, delivery dockets and purchase orders. The purpose of this paper is to introduce the Construction IT Alliance eXchange (CITAX) project and, in particular, to outline the work carried out-to-date by a special interest group within the project. They are seeking to define a universal set of eXtensible Mark-Up Language (XML) message standards that will allow suppliers and contractors to exchange information with each other in supply chain activity. …

Building Bridges: The Transition From Preschool To Primary School For Children In Ireland, Mary O'Kane

Doctoral

The overarching aim of this study was to provide an information base on the transition from preschool to formal schooling in Ireland, and to improve understanding about how best to support children’s learning during this time. The theoretical framework for the project was based on the ecological systems model of development proposed by Bronfenbrenner. As there was no previous Irish research in this area, the study took an exploratory approach, and drew on a variety of sources to present the perspectives of preschool practitioners, primary school teachers, parents and children themselves. Phase 1 involved a questionnaire being completed by a …

Towards A Personal Automatic Music Playlist Generation Alogorithm: The Need For Contextual Information, Gordon Reynolds, Dan Barry, Ted Burke, Eugene Coyle

Conference papers

Large music collections afford the listener flexibility in the form of choice, which enables the listener to choose the appropriate piece of music to enhance or complement their listening scenario on-demand. However, bundled with such a large music collection is the daunting task of manually searching through each entry in the collection to find the appropriate song required by the listener. This often leaves the listener frustrated when trying to select songs from a large music collection. In this paper, an overview of existing methods for automatically generating a playlist is discussed. This discussion outlines advantages and disadvantages associated with …

Shared And Mutual Knowledge In Language Learning, Marty Meinardi

Articles

This article discusses the matter of shared knowledge from the perspective of the different deictic centres of understanding. Difficulties, which may result from a possible lack of a shared knowledge between NSs and NNSs due to differences in language experiences and personal backgrounds, are identified.

University Futures: The Direction, Shape And Provision Of Higher Education In The University Of The Future, Arlene Finn, John Ratcliffe, Lorcan Sirr

Reports

The aim of this study is to help create an awareness of the changing milieu within which Higher Education (HE) will operate over coming decades, while concurrently exploring its possible alternative forms. The specific objectives of the study are to review literature relevant to the University of the Future in a global, European and Irish context. We have sought to determine key trends which have the potential to affect the future of Higher Education (and the institutions charged with its delivery), under the headings of Demography, Society, Technology, Governance, Economy and Environment, and to identify different possible formats for the …

A Brief Introduction To Speech Synthesis And Voice Modification, Alan O'Cinneide, David Dorran, Mikel Gainza

Conference papers

For both engineers and linguists, the computer synthesis of natural speech is an objective that would provide many useful applications to human-computer interaction, including the realm of electro-acoustic music. The purpose of this paper is to introduce the area of speech synthesis by providing an overview of the three main methods of computer speech synthesis; namely concatenative, articulatory and formant syntheses. Some aspects of the current state of the technology are illuminated and the final section will explain the author’s motivation and current research approach to the field of voice modification.

Baugruppe - Lessons From Freiburg On Cooperative Housing : Lessons From Freiburg On Cooperative Housing, Joseph Little

Articles

Creating Sustainable Communities in the UK and Ireland

The Genesis of Quartier Vauban

Exploring The Fate Of No Longer Relevant Spatial Information Using A Modified Sternberg Task, Kirsten Burghardt

School of Psychology Theses

Forgetting, the breakdown of memory, is often associated with inconveniences in everyday life when the car key has been left on the kitchen table or when a phone number will simply not come to mind. However, forgetting has its justified and valued place in cognition. Forgetting allows us to remember the place where we parked our car today, rather than two weeks ago, it enables us to update previously incorrect information in our memory, and It gives us the opportunity to move on from unpleasant past experiences.

The Social And Psychological Effects Of Sms Text Messaging, Donna Reid

School of Psychology Theses

This thesis reports an exploration of the phenomenon of mobile phone SMS text messaging and examines the applicability of two key theories of computer-mediated communication that forecast contrasting outcomes of this medium for personal relationship development and maintenance. It explores how SMS texting is being used, the impact it can have on the formation and maintenance of interpersonal relationships, and its attraction to particular groups of users. The importance of individual differences in moderating the use and outcomes of text messaging is emphasised throughout the studies reported. The investigation was split into two phases. An exploratory phase analysed samples of …

Error Performance Of Double Space Time Transmit Diversity Systems, Jingxian Wu, Y. Rosa Zheng, Ashwin Gumaste, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

The theoretical error performance of double space time transmit diversity (DSTTD) system with optimum combining receiver is analyzed in this paper. by employing both spatial multiplexing and transmit diversity in one system, DSTTD provides practical tradeoff between system spectral efficiency and diversity gain. We derive exact analytical expressions to describe the symbol error rate for DSTTD systems. The effects of both diversity gain and antenna interference introduced by spatial multiplexing are quantified in the results. In addition, the performance of DSTTD system with successive interference cancellation is also investigated. Simulation results are in excellent agreement with the theoretical results obtained …

Frequency-Domain Channel Estimation And Equalization For Broadband Wireless Communications, Y. Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency-domain equalization (FDE) is an effective technique for high data rate wireless communication systems suffering from very long intersymbol interference. Most of existing FDE algorithms are limited to quasi-static or slow time-varying fading channels, where least mean squares (LMS) or recursive least squares (RLS) adaptive algorithms were utilized for channel estimation. In this paper, we employ interpolation method to develop channel estimation algorithm in the frequency domain. We show that the new channel estimation algorithm can significantly outperform LMS and RLS algorithms. Numerical examples demonstrate that the new algorithm can track time-varying fading channels with Doppler up to 300-400 Hz. …

Near Optimal Output-Feedback Control Of Nonlinear Discrete-Time Systems In Nonstrict Feedback Form With Application To Engines, Peter Shih, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement-learning based output-adaptive neural network (NN) controller, also referred as the adaptive-critic NN controller, is developed to track a desired trajectory for a class of complex nonlinear discrete-time systems in the presence of bounded and unknown disturbances. The controller includes an observer for estimating states and the outputs, critic, and two action NNs for generating virtual, and actual control inputs. The critic approximates certain strategic utility function and the action NNs are used to minimize both the strategic utility function and their outputs. All NN weights adapt online towards minimization of a performance index, utilizing gradient-descent based rule. …

Neural Network Control Of Robot Formations Using Rise Feedback, Jagannathan Sarangapani, Travis Alan Dierks

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a combined kinematic/torque control law is developed for leader-follower based formation control using backstepping in order to accommodate the dynamics of the robots and the formation in contrast with kinematic-based formation controllers that are widely reported in the literature. A neural network (NN) is introduced along with robust integral of the sign of the error (RISE) feedback to approximate the dynamics of the follower as well as its leader using online weight tuning. It is shown using Lyapunov theory that the errors for the entire formation are asymptotically stable and the NN weights are bounded as opposed …

Optimal Wide Area Controller And State Predictor For A Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

An optimal wide area controller is designed in this paper for a 12-bus power system together with a Static Compensator (STATCOM). The controller provides auxiliary reference signals for the automatic voltage regulators (AVR) of the generators as well as the line voltage controller of the STATCOM in such a way that it improves the damping of the rotor speed deviations of the synchronous machines. Adaptive critic designs theory is used to implement the controller and enable it to provide nonlinear optimal control over the infinite horizon time of the problem and at different operating conditions of the power system. Simulation …

Frequency-Domain Channel Estimation And Equalization For Single Carrier Underwater Acoustic Communications, Y. Rosa Zheng, Chengshan Xiao, T. C. Yang, Wen-Bin Yang

Electrical and Computer Engineering Faculty Research & Creative Works

A new frequency-domain channel estimation and equalization (FDE) scheme is proposed for single carrier (SC) underwater acoustic communications. The proposed SC-FDE employs a small training signal block for initial channel estimation in the frequency domain and converts the estimated transfer function to a desired DFT (discrete Fourier transform) size for channel equalization of the data blocks. The frequency domain equalizer is designed using the linear minimum mean square error criterion. A new phase coherent detection scheme is also proposed and deployed to combat the phase drift due to the instantaneous Doppler in the underwater channels. The channel transfer functions and …

Mobile Speed Estimation For Broadband Wireless Communications, Y. Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new algorithm is proposed to estimate mobile speed for broadband wireless communications, which often encounter large number of fading channel taps causing severe intersymbol interference. Theoretical analysis is first derived and practical algorithm is proposed based on the analytical results. The algorithm employs a modified auto-covariance of received signal power to estimate the speed of mobiles. The algorithm is based on the received signals which contain unknown transmitted data, unknown frequency selective multipaths possibly including line-of-sight (LOS) component, and random receiver noise. The algorithm works well for frequency selective Rayleigh and Rician channels. The algorithm is …

Neural Network Controller Development And Implementation For Spark Ignition Engines With High Egr Levels, Jonathan B. Vance, Atmika Singh, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

Past research has shown substantial reductions in the oxides of nitrogen (NOx) concentrations by using 10% -25% exhaust gas recirculation (EGR) in spark ignition (SI) engines (see Dudek and Sain, 1989). However, under high EGR levels, the engine exhibits strong cyclic dispersion in heat release which may lead to instability and unsatisfactory performance preventing commercial engines to operate with high EGR levels. A neural network (NN)-based output feedback controller is developed to reduce cyclic variation in the heat release under high levels of EGR even when the engine dynamics are unknown by using fuel as the control input. A separate …

On The Error Performance Of Wireless Systems With Frequency Selective Fading And Receiver Timing Phase Offset, Jingxian Wu, Y. Rosa Zheng, Khaled Ben Letaief, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Heat Transfer Coefficients In A High-Pressure Bubble Column, Chengtian Wu, Muthanna H. Al-Dahhan, Anand Prakash

Chemical and Biochemical Engineering Faculty Research & Creative Works

Time-Averaged Local Heat Transfer Coefficients Were Studied in a 0.16 M Inner Diameter High-Pressure Air-Water Bubble Column. the Effects of the Superficial Gas Velocity (Up to 0.30 M/s), Pressure (Up to 10 Bar), Probe Position, and Probe Orientation Were Investigated. the Heat Transfer Coefficients Increased with Superficial Gas Velocity, and the Values in the Center of the Column Were 9-16% Greater Than Those Near the Wall Region under Atmospheric Pressure (1 Bar). with the Increase in Pressure, the Heat Transfer Coefficients Decreased Due to Combined Effects of Bubble Size Decreasing, Gas Holdup Increasing, and Bubble Number Increasing. the Heat Transfer …