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2004

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An Exploratory Study Of How Decisions Are Made In The Yield Management Environment Of Four Star Dublin Hotels, Tony Kiely Jan 2004

An Exploratory Study Of How Decisions Are Made In The Yield Management Environment Of Four Star Dublin Hotels, Tony Kiely

Other resources

Yield management in the hotel industry has been described as a method of profitably managing fixed capacity. A critical element of yield management is the decision strategy employed as this determines the degree to which optimum solutions are generated. Recent research has indicated that the use of technology assisted decision optimising models (the management science model) would greatly improve the optimisation of decisions by minimising the need to employ guesswork in achieving optimum solutions. Despite this assurance, yield management remains couched in uncertainty through being inextricably associated with forecasting future demand for a perishable product in an increasingly competitive environment. …


Chemical Solution Deposition Of Electronic Oxide Films, Robert W. Schwartz, Theodor Schneller, Rainer Waser Jan 2004

Chemical Solution Deposition Of Electronic Oxide Films, Robert W. Schwartz, Theodor Schneller, Rainer Waser

Materials Science and Engineering Faculty Research & Creative Works

The chemical solution deposition (CSD) technique as a highly flexible method for the fabrication of electronic oxide thin films is reviewed. Various chemical aspects of different approaches are discussed, including sol-gel, hybrid, and metallo-organic decomposition (MOD) routes, which all have been successfully applied for the deposition of this class of materials. Principles of the selection and properties of the educts, the mechanism of film crystallization, and tailoring of microstructure through manipulation of deposition parameters are reported. the role of thermodynamics on the phase transformation process is also reviewed. Finally, some of the applications for chemical solution-derived thin films currently under …


Solid State Aircraft Concept Overview, M. Shahinpoor, P. Jenkins, C. Smith, Kakkattukuzhy M. Isaac, T. Dalbello, Anthony Colozza Jan 2004

Solid State Aircraft Concept Overview, M. Shahinpoor, P. Jenkins, C. Smith, Kakkattukuzhy M. Isaac, T. Dalbello, Anthony Colozza

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Due to recent advances in polymers, photovoltaics, and batteries a unique type of aircraft may be feasible. This is a "solid-state" aircraft, with no conventional mechanical moving parts. Airfoil, propulsion, energy production, energy storage and control are combined in an integrated structure. The key material of this concept is an ionic polymeric-metal composite (IPMC) that provides source of control and propulsion. This material has the unique capability of deforming in an electric field and returning to its original shape when the field is removed. Combining the IPMC with thin-film batteries and thin-film photovoltaics provides both energy source and storage in …


Relationship Of Effective Serve Reception Passing To Side Out Offense In Iowa City West Volleyball Matches, Craig A. Pitcher Jan 2004

Relationship Of Effective Serve Reception Passing To Side Out Offense In Iowa City West Volleyball Matches, Craig A. Pitcher

Dissertations and Theses @ UNI

The purpose of this study was to indicate the relationship of effective serve reception to side out offense in Iowa City West volleyball matches. Subjects were member of the 2002 Iowa City West varsity volleyball team. Iowa City West volleyball team was selected for the study based on availability of game tapes throughout the 2002 season. All taped varsity matches were viewed for the study analysis. All reception passes were given a pass value of three, two, one, or zero. Each pass was also categorized into offensive outcomes, kill, play on, or error. The results of the Person correlation test …


Biup3: Boundary Topological Invariant Of 3d Objects Through Front Propagation At A Constant Speed, Xiaoqing Frank Liu Jan 2004

Biup3: Boundary Topological Invariant Of 3d Objects Through Front Propagation At A Constant Speed, Xiaoqing Frank Liu

Computer Science Faculty Research & Creative Works

Topological features constitute the highest abstraction in object representation. Euler characteristic is one of the most widely used topological invariants. The computation of the Euler characteristic is mainly based on three well-known mathematical formulae, which calculate either on the boundary of object or on the whole object. However, as digital objects are often non-manifolds, none of the known formulae can correctly compute the genus of digital surfaces. In this paper, we show that a new topological surface invariant of 3D digital objects, called BIUP/sup 3/, can be obtained through a special homeomorphic transform: front propagation at a constant speed. BIUP/sup …


Priority Assessment Of Software Requirements From Multiple Perspectives, Xiaoqing Frank Liu, Chandra Sekhar Veera, Yan Sun, Kunio Noguchi, Yuji Kyoya Jan 2004

Priority Assessment Of Software Requirements From Multiple Perspectives, Xiaoqing Frank Liu, Chandra Sekhar Veera, Yan Sun, Kunio Noguchi, Yuji Kyoya

Computer Science Faculty Research & Creative Works

The development of complex software systems involves collecting software requirements from various stakeholders. Often stakeholder perceptions conflict during the requirements elicitation phase. An effective technique to resolve such a conflict is needed. We presented a framework that prioritizes software requirements gathered from multiple stakeholders by incorporating inter-perspective relationships, which is not addressed by existing priority assessment techniques. We use a relationship matrix to analyze the impact between requirements and facilitate the integration process which assesses their priorities based on their relationships from multiple perspectives. It allows the development team to resolve conflicts effectively and concentrate their valuable time and resources …


The Robustness Of Resource Allocation In Parallel And Distributed Computing Systems, Shoukat Ali, Howard Jay Siegel, A. A. Maciejewski Jan 2004

The Robustness Of Resource Allocation In Parallel And Distributed Computing Systems, Shoukat Ali, Howard Jay Siegel, A. A. Maciejewski

Electrical and Computer Engineering Faculty Research & Creative Works

This paper gives an overview of the material to be discussed in the invited keynote presentation by H. J. Siegel. Performing computing and communication tasks on parallel and distributed systems involves the coordinated use of different types of machines, networks, interfaces, and other resources. Decisions about how best to allocate resources are often based on estimated values of task and system parameters, due to uncertainties in the system environment. An important research problem is the development of resource management strategies that can guarantee a particular system performance given such uncertainties. We have designed a methodology for deriving the degree of …


A Scalable Approach For Reliable Downstream Data Delivery In Wireless Sensor Networks, Seung Jong Park, Ramanuja Vedantham, Raghupathy Sivakumar, Ian F. Akyildiz Jan 2004

A Scalable Approach For Reliable Downstream Data Delivery In Wireless Sensor Networks, Seung Jong Park, Ramanuja Vedantham, Raghupathy Sivakumar, Ian F. Akyildiz

Computer Science Faculty Research & Creative Works

There exist several applications of sensor networks where reliability of data delivery can be critical. While the redundancy inherent in a sensor network might increase the degree of reliability, it by no means can provide any guaranteed reliability semantics. In this paper, we consider the problem of reliable sink-to-sensors data delivery. We first identify several fundamental challenges that need to be addressed and are unique to a wireless sensor network environment. We then propose a scalable framework for reliable down-stream data delivery that is specifically designed to both address and leverage the characteristics of a wireless sensor network, while achieving …


A Discrete-Time Model For Triply Selective Mimo Rayleigh Fading Channels, Chengshan Xiao, Jingxian Wu, Sang-Yick Leong, Y. Rosa Zheng, Khaled Ben Letaief Jan 2004

A Discrete-Time Model For Triply Selective Mimo Rayleigh Fading Channels, Chengshan Xiao, Jingxian Wu, Sang-Yick Leong, Y. Rosa Zheng, Khaled Ben Letaief

Electrical and Computer Engineering Faculty Research & Creative Works

A statistical discrete-time model is proposed for simulating wideband multiple-input multiple-output (MIMO) fading channels which are triply selective due to angle spread, Doppler spread, and delay spread. The new discrete-time MIMO channel model includes the combined effects of the transmit filter, physical MIMO multipath channel fading, and receive filter, and it has the same sampling period as that of the MIMO receiver. This leads to very efficient simulation of physical continuous-time MIMO channels. A new method is also presented to efficiently generate the MIMO channel stochastic coefficients. The statistical accuracy of the discrete-time MIMO channel model is rigorously verified through …


A Method For Enhancing The Snapshot Performance In San Volume Manager, Chang-Soo Kim, Dong-Jae Kang, Young-Ho Kim, Hag-Young Kim, Myoung-Jun Kim, Yu-Hyeon Bak Jan 2004

A Method For Enhancing The Snapshot Performance In San Volume Manager, Chang-Soo Kim, Dong-Jae Kang, Young-Ho Kim, Hag-Young Kim, Myoung-Jun Kim, Yu-Hyeon Bak

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.


A New Estimative Current Mode Control Technique For Dc-Dc Converters Operating In Discontinuous Conduction Mode, Mehdi Ferdowsi, Zhong Nie, Ali Emadi Jan 2004

A New Estimative Current Mode Control Technique For Dc-Dc Converters Operating In Discontinuous Conduction Mode, Mehdi Ferdowsi, Zhong Nie, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

A new digital control technique for power converters operating in discontinuous conduction mode (DCM) is introduced and applied to a boost converter. In contrast to the conventional analogue control methods, the principal idea of this new control scheme is to use real-time analysis and estimate the required on-time of the switch based on the dynamic of the system. The proposed control algorithm can easily be programmed in a digital signal processor (DSP). This novel technique is applicable to any converter operating in DCM including power factor correctors (PFC). However, this work mainly focuses on the boost topology. In this paper, …


Death Of A Mother, Mary Moynihan Jan 2004

Death Of A Mother, Mary Moynihan

Books/Book Chapters

No abstract provided.


The Social Effects Of Psychism: Spiritual Experience And The Construction Of Privatized Religion, Marty Laubach Jan 2004

The Social Effects Of Psychism: Spiritual Experience And The Construction Of Privatized Religion, Marty Laubach

Sociology and Anthropology Faculty Research

What is the relationship between spiritual experiences and privatized religion? This study defines spiritual experiences in terms of “psychism,” or psychic intrusions in the stream of consciousness that are not perceived by the actor as originating within the “self.” Intrusions interpreted as psychism are regarded by the actor as having the same facticity as empirical experience and are regarded as “proof” of an esoteric belief system. Psychism originated beliefs are therefore resistant to refutation or change, and support spiritual autonomy. Psychism theory is tested using 1988 GSS data on religious beliefs, where psychism is measured using GSS questions on “paranormal” …


Real-Time Sound Source Separation: Azimuth Discrimination And Resynthesis, Dan Barry, Robert Lawlor, Eugene Coyle Jan 2004

Real-Time Sound Source Separation: Azimuth Discrimination And Resynthesis, Dan Barry, Robert Lawlor, Eugene Coyle

Conference papers

We present a real-time sound source separation algorithm which performs the task of source separation based on the lateral displacement of a source within the stereo field. The algorithm exploits the use of the pan pot as a means to achieve image localisation within stereophonic recordings. As such, only an interaural intensity difference exists between left and right channels for a single source. Gain scaling and phase cancellation techniques are used in the frequency domain to expose frequency dependent nulls across the Azimuth plane. The position of these nulls in conjuction with magnitude estimation and grouping techniques are then used …


Harmonic Sound Source Separation Using Fir Comb Filters, Mikel Gainza, Robert Lawlor, Eugene Coyle Jan 2004

Harmonic Sound Source Separation Using Fir Comb Filters, Mikel Gainza, Robert Lawlor, Eugene Coyle

Conference papers

A technique for separating harmonic sound sources using FIR comb filters is presented. First, a pre-processing task is performed by a multipitch estimator to detect the pitches that the signal is composed of. Then, a method based on the Short Time Fourier Transform (STFT) is utilized to iteratively extract the harmonics belonging to a given source by using FIR comb filters. The presented approach improves upon exising sinusoidal model approaches in terms of the perceptual quality of the extracted signal.


Henrietta Street Conservation Plan, Tracy Pickerill, John Montague, Shaffrey Associates (Architects), Carrig Conservation Ltd., Lee Mccullough & Partners (Engineers), Boylan Farrelly (Quantity Surveyors) Jan 2004

Henrietta Street Conservation Plan, Tracy Pickerill, John Montague, Shaffrey Associates (Architects), Carrig Conservation Ltd., Lee Mccullough & Partners (Engineers), Boylan Farrelly (Quantity Surveyors)

Reports

The objectives behind the Henrietta Street Conservation Plan are to re-affirm the significance of Henrietta Street; to identify the issues that undermine the importance of the street and to set out policies aimed at protecting the aspects of the street which are of importance into the future.


Perspectives On Epidemic: The Yellow Fever In 1793 Philadelphia, Katherine Polak Jan 2004

Perspectives On Epidemic: The Yellow Fever In 1793 Philadelphia, Katherine Polak

Constructing the Past

This article discusses the Yellow Fever epidemic of 1793, and how there are several different accounts of what happened then. It also notes that the official descriptions given by the doctors of the time are not the entire story and that they leave some important things out.


Efficient Path Search In Intermodal Transportation Optimization, Daniel Y. Yankov Jan 2004

Efficient Path Search In Intermodal Transportation Optimization, Daniel Y. Yankov

Theses

As the economies of the world become more interrelated and Supply Chains are globalizing, the need arises to create efficient transportation network. This reality in conjunction with conservation of fuel and environmental friendliness gives rise to the research of Efficient Intermodal Transportation System. In particular, the underutilization of railroads in the United States motivates us to research the development of optimal procedures in the transportation of containers in a rail network. With this thesis we search for a cost, time and capacity effective algorithm for solving transportation problem in a graph of intermodal centers (IMC's). We consider discrete model of …


A Change Impact Dependency Measure For Predicting The Maintainability Of Source Code, Xiaoqing Frank Liu Jan 2004

A Change Impact Dependency Measure For Predicting The Maintainability Of Source Code, Xiaoqing Frank Liu

Computer Science Faculty Research & Creative Works

We first articulate the theoretic difficulties with the existing metrics designed for predicting software maintainability. To overcome the difficulties, we propose to measure a purely internal and objective attribute of code, namely change impact dependency, and show how it can be modeled to predict real change impact. The proposed base measure can be further elaborated for evaluating software maintainability.


A Generic Oo Architecture Language For Semantics Analysis Of Oo Specification, Xiaoqing Frank Liu Jan 2004

A Generic Oo Architecture Language For Semantics Analysis Of Oo Specification, Xiaoqing Frank Liu

Computer Science Faculty Research & Creative Works

Formal specification enables a rigorous analysis and model checking for ensuring the correctness of specification. Formal OO specification methods are of mathematical nature and the semantics of specification is purposely defined such that it is not related to the semantics of code. We propose a new language, which will lay a common semantics ground for both specification and code.


Ergodic Capacity Of Mimo Triply Selective Rayleigh Fading Channels, Chengshan Xiao, Y. Rosa Zheng Jan 2004

Ergodic Capacity Of Mimo Triply Selective Rayleigh Fading Channels, Chengshan Xiao, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

New results are presented for the ergodic capacity of spatially-correlated, time-varying and frequency-selective (i.e., triply selective) MIMO Rayleigh fading channels. Simplified capacity formulas are also derived for special cases such as SIMO and MISO triply selective fading channels. A closed form formula is proposed that quantifies the effect of the frequency-selective fading on the ergodic capacity into an intersymbol interference (ISI) degradation factor. It is discovered that, in general frequency-selective MIMO channels, the ISI inter-tap correlations reduce the ergodic capacity compared to the frequency flat fading channel. Only in the special case when the fading does not have ISI inter-tap …


Neural Network Based Classification Of Road Pavement Structures, V. Venayagamoorthy, D. Allopi, Ganesh K. Venayagamoorthy Jan 2004

Neural Network Based Classification Of Road Pavement Structures, V. Venayagamoorthy, D. Allopi, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Roads have formed the basic infrastructure of commerce since flints and other tools and artifacts were first exchanged along the trade routes of prehistory. Roadways are very large, in volume, in extent, and in value. They also wear out, and their useful life is directly proportional to their initial strength and inversely proportional to the number of heavy goods vehicles using them. Therefore, the increasing complexity of road transportation needs advanced techniques for effective design of pavements. This paper proposes an intelligent technique using neural networks to classify different types of road pavement structures, which is essential in estimating bearing …


Data Mining Of Substation Relay Data, Badrul H. Chowdhury, Mythili Chaganti Jan 2004

Data Mining Of Substation Relay Data, Badrul H. Chowdhury, Mythili Chaganti

Electrical and Computer Engineering Faculty Research & Creative Works

Data mining aims to make sense of data by revealing meaningful relationships. This paper discusses data mining techniques applied to data recorded by over current relays at several substations. The purpose is to classify faults, verify relay settings and determine fault induced trip per substations. One of the most demanding tasks at hand is to study the data residing in the relays on a statistical basis. C4.5 approach of data mining (decision tree induction) is discussed in this paper.


An Improved Optimal Elemental Method For Updating Finite Element Models, Zhongdong Duan, B. F. Spencer, Guirong Yan, Jinping Ou Jan 2004

An Improved Optimal Elemental Method For Updating Finite Element Models, Zhongdong Duan, B. F. Spencer, Guirong Yan, Jinping Ou

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Optimal Matrix Method and Optimal Elemental Method Used to Update Finite Element Models May Not Provide Accurate Results. This Situation Occurs When the Test Modal Model is Incomplete, as is Often the Case in Practice. an Improved Optimal Elemental Method is Presented that Defines a New Objective Function, and as a Byproduct, Circumvents the Need for Mass Normalized Modal Shapes, Which Are Also Not Readily Available in Practice. to Solve the Group of Nonlinear Equations Created by the Improved Optimal Method, the Lagrange Multiplier Method and Matlab Function Fmincon Are Employed. to Deal with Actual Complex Structures, the Float-Encoding …


Learning To Learn-Concepts In A First Power Engineering Course, Badrul H. Chowdhury Jan 2004

Learning To Learn-Concepts In A First Power Engineering Course, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

Three well-known and widely accepted concepts in educational psychology are revisited. These are "inventory of learning styles," "taxonomy of educational objectives," and "metacognition." Relationships among these concepts are highlighted. Often, a student can develop his (or her) own learning style by the process of metacognition. Ideas are borrowed from these concepts for use in a first-level power systems course. It is beyond a doubt that both cognitive and metacognitive skills are necessary for students to succeed in any course. While a semester-long power systems course leaves little time for critical thinking and passive reflection for students, certain activities may very …


Neural Network Controller For Manipulation Of Micro-Scale Objects, Vijayakumar Janardhan, Pingan He, Jagannathan Sarangapani Jan 2004

Neural Network Controller For Manipulation Of Micro-Scale Objects, Vijayakumar Janardhan, Pingan He, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement learning-based neural network (RLNN) controller is presented for the manipulation and handling of micro-scale objects in a microelectromechanical system (MEMS). In MEMS, adhesive, surface tension, friction and van der Waals forces are dominant. Moreover, these forces are typically unknown. The RLNN controller consists of an action NN for compensating the unkoown system dynamics, and a critic NN to tune the weights of the action NN. Using the Lyapunov approach, the uniformly ultimate houndedness (UUB) of the closed-loop tracking error and weight estimates are shown by using a novel weight updates. Simulation results are presented to substantiate the …


Neuroidentification Of System Parameters Of The Upfc In A Multimachine Power System, Radha P. Kalyani, Ganesh K. Venayagamoorthy Jan 2004

Neuroidentification Of System Parameters Of The Upfc In A Multimachine Power System, Radha P. Kalyani, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The crucial factor affecting the modern power systems today is load flow control. The Unified Power Flow Controller is an effective means for controlling the power flow. The UPFC is controlled conventionally using PI controllers. This paper presents the designs of neuroidentifiers that models the system dynamics one-time step ahead making the pathway for the design of adaptive neurocontrollers. Two neuroidentifiers are used for identifying the nonlinear dynamics of a multimachine power system and UPFC, one neuroidentifier for the shunt inverter and another for the series inverter. Simulation results carried out in the PSCAD/EMTDC environments on multimachine power system are …


Deformation Analysis Of Missouri Bridge Approach Embankments, Jonathan L. Robison, Ronaldo Luna Jan 2004

Deformation Analysis Of Missouri Bridge Approach Embankments, Jonathan L. Robison, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Missouri has recently experienced below expectation performance or "the bump-at-the-end of the bridge" phenomena at bridge approach slab transitions. Information on approach slab performance was collected state wide to assess if the problem was limited to regional or geological distribution. Finite element analysis was then used to explore the soil embankment-bridge structure differential settlement in two Missouri bridges; MoDOT Bridge A6031 in Livingston County, and MoDOT Bridge A5834 in Pulaski County. These two cases are indicative of the types of soil conditions encountered in the Northern Glaciated Plains region (deeper compressible foundation soils) and the Southern Ozarks region (shallow rocky …


Boost Integrated Push-Pull Rectifier With Power Factor Correction And Output Voltage Regulation Using A New Digital Control Technique, Zhong Nie, Mehdi Ferdowsi, Ali Emadi Jan 2004

Boost Integrated Push-Pull Rectifier With Power Factor Correction And Output Voltage Regulation Using A New Digital Control Technique, Zhong Nie, Mehdi Ferdowsi, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

An integrated converter is a synthesized converter based on the overall system integration, which is simplified by the system objective and can implement the system functions similar to the discrete converters. An integrated converter consists of converter sets; each converter set has a special function defined by the designer. A family of DC/DC Boost based integrated rectifiers with two active switches can be derived by the integration concept. In this paper, Boost + Push-Pull integrated converter is introduced and derived. To regulate the output voltage and shape the input current, a new simple digital control method is applied. In contrast …


Cause And Effects Of Voltage Collapse -- Case Studies With Dynamic Simulations, Feng Dong, Mariesa Crow, Badrul H. Chowdhury, Levent Acar Jan 2004

Cause And Effects Of Voltage Collapse -- Case Studies With Dynamic Simulations, Feng Dong, Mariesa Crow, Badrul H. Chowdhury, Levent Acar

Electrical and Computer Engineering Faculty Research & Creative Works

Voltage collapse studies are made to gain an insight into mechanisms that drive a system into collapse. The inter-play of generator controls in local and external areas are explored. Simulations are carried out on a medium sized network by a transient dynamic simulation program. Simulation results help to better understand remediation strategies. The time dependent characteristics of corrective controls are investigated.