Engineering Commons^™

A Novel Model To Measure Supplier Performance In The Supplier Selection Process, Alptekin Ulutas, Senevi Kiridena, Peter Gibson

Peter R Gibson

Supplier evaluation has become a significant topic over the past decades, as companies have started to become more outsourced oriented. However, previous research on this topic has not paid adequate attention to the limitations associated with availability of accurate and reliable data relating to the performance of potential suppliers. In an attempt to address this issue, this paper proposes a novel supplier evaluation model that can handle imprecise quantitative and qualitative data. Additionally, Decision Maker’s opinions regarding both qualitative and quantitative criteria are incorporated into this model so that a more comprehensive and realistic assessment of supplier performance can be …

Indoor Localisation Using A Context-Aware Dynamic Position Tracking Model, Montserrat Ros, Joshua Boom, Gavin De Hosson, Matthew D'Souza

Dr Montserrat Ros

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Indoor wireless localisation is a widely sought feature for use in logistics, health, and social networking applications. Low-powered localisation will become important for the next generation of pervasive media applications that operate on mobile platforms. We present an inexpensive and robust context-aware tracking system that can track the position of users in an indoor environment, using a wireless smart meter network. Our context-aware tracking system combines wireless trilateration with a …

The Application Of Systems Engineering Principles To Model Lithium Ion Battery Voltage, George Gibbs

Master's Theses

The objective of this project is to present a Lithium Ion battery voltage model derived using systems engineering principles. This paper will describe the details of the model and the implementation of the model in practical use in a power system. Additionally, the model code is described and results of the model output are compared to battery cell test data. Finally, recommendations for increased model fidelity and capability are summarized.

The modeling theory has been previously documented in the literature but detailed implementation and application of the modeling theory is shown. The detailed battery cell test voltage profiles are proprietary; …

A Spatial Agent-Based Model To Explore Scenarios Of Adaptation To Climate Change In An Alpine Tourism Destination, Stefano Balbi, Pascal Perez, Carlo Giupponi

Professor Pascal Perez

A vast body of literature suggests that the European Alpine region may be one of the most sensitive to climate change impacts. Adaptation to climate change of Alpine socioecosystems is increasingly becoming an issue of interest for the scientific community while the people of the Alps are often unaware of or simply ignore the problem. ClimAlpTour is a European research project of the Alpine Space Programme, bringing together institutions and scholars from all countries of the Alpine arch, in view of dealing with the expected decrease in snow and ice cover, which may lead to a rethinking of tourism development …

Simamph: An Agent-Based Simulation Model For Exploring The Use Of Psychostimulants And Related Harm Amongst Young Australians, Pascal Perez, Anne Dray, David Moore, Paul Dietze, Gabriele Bammer, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan Hudson, Lisa Maher

Professor Pascal Perez

Background: Computer simulations provide a useful tool for bringing together diverse sources of information in order to increase understanding of the complex aetiology of drug use and related harm, and to inform the development of effective policies. In this paper, we describe SimAmph, an agent-based simulation model for exploring how individual perceptions, peer influences and subcultural settings shape the use of psychostimulants and related harm amongst young Australians. Methods: We present the conceptual architecture underpinning SimAmph, the assumptions we made in building it, the outcomes of sensitivity analysis of key model parameters and the results obtained when we modelled a …

Simreef: An Agent-Based Model To Address Coastal Management Issues In The Yucatan Peninsula, Mexico, Pascal Perez, A Dray, Deborah Cleland, Jesus Ernesto Arias-Gonzalez

Professor Pascal Perez

The northernmost part of the Mesoamerican Barrier Reef (MBR) runs along the eastern Yucatan peninsula (Mexico). Over two decades, sprawling coastal tourism development and over-exploitation of marine resources have considerably reduced fringing reef’s ecological functions. SimReef is an interactive model designed to better understand the interactions between regional and local drivers strongly influencing the health of coral reefs. SimReef’s development follows a collective design approach and an inductive process whereby dynamics are represented by data-driven relationships. Experts and stakeholders participate to the designing phase in order to help calibrating the model and to support a consensual validation of the results.

An Ontology-Based Simulation Model Exploring The Social Contexts Of Psychostimulant Use Among Young Australians, Pascal Perez, Anne Dray, Paul Dietze, David Moore, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan L. Hudson, Lisa Maher, Gabriele Bammer

Professor Pascal Perez

The principal anthropogenic factors driving reef degradation have been known for years, if not decades. Overfishing, sedimentation and nutrient loads are just some of the key impacts of human activities in and around reef communities. Therefore, the future of reefs does not rely on generating new knowledge, but rather on implementing and integrating the knowledge we already have. This will require creating effective links between researchers, managers and communities to promote mutual learning, negotiation and collaborative action for reef management. Combining agent-based models and role-play games, through a technique known as Companion Modelling (ComMod), creates a dynamic and interactive setting …

Are Drug Detection Dogs And Mass-Media Campaigns Likely To Be Effective Policy Responses To Psychostimulant Use And Related Harm? Results From An Agent-Based Simulation Model, David Moore, Lisa Maher, Christine Siokou, Rachael Green, Anne Dray, Rebecca Jenkinson, Susan Hudson, Gabriele Bammer, Pascal Perez, Paul Dietze

Professor Pascal Perez

Background Agent-based simulation models can be used to explore the impact of policy and practice on drug use and related consequences. In a linked paper (Perez et al., 2011), we described SimAmph, an agent-based simulation model for exploring the use of psychostimulants and related harm amongst young Australians. Methods In this paper, we use the model to simulate the impact of two policy scenarios on engagement in drug use and experience of drug-related harm: (i) the use of passive-alert detection (PAD) dogs by police at public venues and (ii) the introduction of a mass-media drug prevention campaign. Results The findings …

A Microslip Model Of The Bonding Process In Ultrasonic Wire Bonders Part I: Transient Response, C M. Hu, N Guo, H Du, W H. Li, M Chen

Dr Haiping Du

Ultrasonic wire bonders with precision capillary tips are widely used for bonding electrical wires to IC chips and circuits. The industry is driving wire-bonding technology towards increased yields, decreased pitch, and ever decreasing cost. However, many technical and material issues will be involved in achieving these goals, such as bond quality monitoring, new failure modes, reliability problems in new plastic mold compounds, and increasing wire sweep problems, in particular lack of the quantitative understanding and validated mathematical model of the bonding process. In this paper, a microslip model is proposed for the bonding process based on the bonding pattern observed, …

A Deformable Model With Cellular Neural Network, Yongmin Zhong, Bijan Shirinzadeh, Gursel Alici, Julian Smith

Gursel Alici

This paper presents a new methodology for deformable models by drawing an analogy between cellular neural network (CNN) and elastic deformation. The potential energy stored in an elastic body as a result of a deformation caused by an external force is propagated among mass points by the local connectivity of cells and the CNN dynamics. An improved CNN model is developed for propagating the energy generated by the external force on the object surface. A method is presented to derive the internal forces from the potential energy distribution established by the CNN. The methodology proposed in this paper can not …

Model-Based Adaptive Control Of Piezoelectric Actuation Systems, Hwee Choo Liaw, Denny Oetomo, Bijan Shirinzadeh, Gursel Alici

Gursel Alici

This paper proposes a model-based adaptive control methodology for piezoelectric actuation systems to follow specified motion trajectories. This is motivated by a search for an effective control strategy to deal with the problem of parametric uncertainties such as disturbance and hysteresis effects. The proposed adaptive law is formulated by combining a parameter compensator and a conventional PD feedback control for a system to drive its position tracking error converging to zero. The fundamental concept lies in the properties of a quasinatural potential function, which allows a saturated position error function in the control formulation. Implementation of the control law requires …

Mathematical Model And Experimental Exploration Of The Nanoinjector Lance Array, Nathan C. Toone

Theses and Dissertations

The Nanoinjector Lance Array has been developed to inject foreign material into thousands of cells at once using electrophoresis to attract and repel particles to and from the electrically-charged lances. A mathematical computer model simulating the motion of attracted or repelled proteins informs the design of the nanoinjection lance array system. The model is validated by accurately predicting protein velocity in electrophoresis experiments. A complete analysis of parameters is conducted via simulations and specific research questions regarding the counter electrode of the nanoinjector lance array system are explored using the model. A novel technique for fabricating lance arrays from collapsed …

A Physical Model For The Kink Effect In Inalas/Ingaas Hemt’S, Mark Somerville, Alexander Ernst, Jesus Del Alamo

Mark Somerville

We present a new model for the the kink effect in InAlAs/InGaAs HEMTs. The model suggests that the kink is due to a threshold voltage shift which arises from a hole pile-up in the extrinsic source and an ensuing charging ofthe surface and/or the buffer-substrate interface. The model captures many of the observed behaviors of the kink, including the kink's dependence on bias, time, temperature, illumination, and device structure. Using the model, we have developed a simple equivalent circuit, which reproduced well the kink's dc characteristics, its time evolution in the nanosecond range, and its dependence on illumination.

A New Computational Model To Augment The Design Of Microfluidic Separations: Electric Field Assisted, Hydrodynamic Chromatography, Jeffrey D. Wells

Master's Theses

This project encompasses the implementation of a computational model to simulate the microfluidic separation of like-charged particles in a continuous flow environment. By accomplishing this task the model can be used to optimize future fractionations by tailoring the process parameters to the properties of the target particles. The primary goal of this project is to develop a vectorized code within Matlab® that captures a sufficient quantity of the physics in separations to assist with the optimization and design of microfluidic systems.

This project differs from other computational models in that it utilizes a personal computer to run the simulation in …

A New Approximate Model For Microscopy Imaging, Heidy Sierra, Dana Brooks, Charles Dimarzio

Dana Brooks

There has been increasing interest in recent years in techniques for microscopic examination of optically thick transparent objects. A number of phase imaging modalities have been developed to address this need. If a stack of images is acquired through focusing, the image at a given focal plane is contaminated by out-of-focus information coming from other planes [1]. There is a need to develop 3D imaging models for phase microscopes that will allow deconvolution, or more generally inverse reconstruction, techniques to be developed. Thus there is a need for an image formation model for phase microscopy that is able to maintain …

A New Approximate Model For Microscopy Imaging, Heidy Sierra, Dana Brooks, Charles Dimarzio

Charles A. DiMarzio

There has been increasing interest in recent years in techniques for microscopic examination of optically thick transparent objects. A number of phase imaging modalities have been developed to address this need. If a stack of images is acquired through focusing, the image at a given focal plane is contaminated by out-of-focus information coming from other planes [1]. There is a need to develop 3D imaging models for phase microscopes that will allow deconvolution, or more generally inverse reconstruction, techniques to be developed. Thus there is a need for an image formation model for phase microscopy that is able to maintain …

Assessing The Validity Of Brain Glucose Concentration Measurement Using Microdialysis, Damon Anthony Vinciguerra

Master’s Theses

Brain functions, such as learning, orchestrating locomotion, memory recall, and processing information, all require glucose as a source of energy. During these functions, the glucose concentration decreases as the glucose is being consumed by brain cells. By measuring this drop in concentration, it is possible to determine which parts of the brain are used during specific functions and consequently, how much energy the brain requires to complete the function. One way to measure in vivo brain glucose levels is with a microdialysis probe. The drawback of this analytical procedure, as with many steadystate fluid flow systems, is that the probe …

Development And Application Of A Hydroclimatological Stream Temperature Model Within The Soil And Water Assessment Tool, Darren L. Ficklin, Yuzhou Luo, Iris T. Stewart-Frey, Edwin P. Maurer

Civil, Environmental and Sustainable Engineering

We develop a stream temperature model within the Soil and Water Assessment Tool (SWAT) that reflects the combined influence of meteorological (air temperature) and hydrological conditions (streamflow, snowmelt, groundwater, surface runoff, and lateral soil flow) on water temperature within a watershed. SWAT currently uses a linear air-stream temperature relationship to determine stream temperature, without consideration of watershed hydrology. As SWAT uses stream temperature to model various in-stream biological and water quality processes, an improvement of the stream temperature model will result in improved accuracy in modeling these processes. The new stream temperature model is tested on seven coastal and mountainous …

A Simulation Analysis Of Photovoltaic Ac Module Integrated Converters In Parallel, Under Controlled Edge Shading Conditions, Lynette O'Callaghan, Mick Mckeever, Brian Norton

Conference Papers

A DC and AC power simulation comparison of: a Photovoltaic (PV) array with a modular, parallel, AC converter configuration; and a series, string configuration with a central AC converter, is presented. The systems are simulated using a comprehensive range of edge shading scenarios and irradiance conditions. Power control and transformation circuitry must be designed for shade and module mismatch tolerance to prevent over-proportional power to shade losses, as average losses from Building Integrated PV (BIPV) systems are approximately 20 to 25%, due to shade, mismatch, differences in orientation and inclination, and temperature effects. 59.4% of the simulations showed gains in …

Departure Time Choice Analysis Using Ordered Response Probit Model: Journey To Work Trip In Dhaka City Of Bangladesh, Ahm Mehbub Anwar

SMART Infrastructure Facility - Papers

No abstract provided.

Indoor Localisation Using A Context-Aware Dynamic Position Tracking Model, Montserrat Ros, Joshua Boom, Gavin De Hosson, Matthew D'Souza

Faculty of Engineering - Papers (Archive)

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Indoor wireless localisation is a widely sought feature for use in logistics, health, and social networking applications. Low-powered localisation will become important for the next generation of pervasive media applications that operate on mobile platforms. We present an inexpensive and robust context-aware tracking system that can track the position of users in an indoor environment, using a wireless smart meter network. Our context-aware tracking system combines wireless trilateration with a …

Shear Strength Model For Sediment-Infilled Rock Discontinuities And Field Applications, Buddhima Indraratna, Wuditha N. Premadasa, Jan Anton Nemcik, Mylvaganam Jayanathan

Faculty of Engineering - Papers (Archive)

Discontinuities have a great influence on the reduction of rock mass shear strength depending on the geometry, roughness and the nature of infill sediments. These discontinuities are generally filled with different types of sediments. When the infill sediments are saturated, they make a considerable impact on the overall strength of the rock mass. Most infilled discontinuities in the field are overconsolidated due to various factors such as climatic and weathering conditions, as well as hydrothermal alteration. The increase in the thickness of joint infill subdues the otherwise prominent role of joint roughness. This paper presents some of the existing mathematical …

A Novel Model To Measure Supplier Performance In The Supplier Selection Process, Alptekin Ulutas, Senevi Kiridena, Peter Gibson

Faculty of Engineering - Papers (Archive)

Supplier evaluation has become a significant topic over the past decades, as companies have started to become more outsourced oriented. However, previous research on this topic has not paid adequate attention to the limitations associated with availability of accurate and reliable data relating to the performance of potential suppliers. In an attempt to address this issue, this paper proposes a novel supplier evaluation model that can handle imprecise quantitative and qualitative data. Additionally, Decision Maker’s opinions regarding both qualitative and quantitative criteria are incorporated into this model so that a more comprehensive and realistic assessment of supplier performance can be …

Introduction To The Sydney Soil Model, Martin D. Liu, John P. Carter, David W. Airey

Faculty of Engineering - Papers (Archive)

In this paper a new constitutive model recently suggested by the authors, referred to as the Sydney Soil model, is introduced. The Sydney Soil Model is formulated within the framework of Critical State Soil Mechanics and is suitable for describing the behaviour of structured soils including both clays and sands. In the proposed model, the mechanical behaviour of soil is divided into two parts, that at a reference state and that attributed to the influence of soil structure. The reference state behaviour is formulated according to the soil properties at the critical state of deformation, based on the concept of …

Application Of Centroidal Voronoi Diagram In Numerical Model Of Microforming Process, Hai Na Lu, Dong Bin Wei, Zheng Yi Jiang

Faculty of Engineering - Papers (Archive)

Grain size, shape and orientation play an important role on the deformability of micro workpiece as the geometrical dimensions approach to a characteristic scale in micro-forming process. This paper addresses the three-dimensional (3D) finite element (FE) model with weighed centroidal voronoi diagram (WCVD). Steady-state grains are generated when the voronoi generating points approach the grain centroid utilising a simplex integration algorithm. As a result of the centroidal process, the topological features of grains advance the uniform and steady state gradually, which may cause a decrease of interfacial energy. The grain size distribution is compared between the 3D domain and random …

A Validated Thermal Model Of Bead-On-Plate Welding, Djarot Darmadi, A K. Tieu, John Norrish

Faculty of Engineering - Papers (Archive)

In this paper, finite element model is used to carry out thermal analysis of bead-on-plate welding. The model followed the proposed five step strategies which were then built into a model to obtain temperature history at the positions of thermocouples. Temperature field was also evaluated by comparing predicted weld bead with the actual weld bead. Using these proposed strategies, well matched temperature histories and temperature field have been obtained.

Soac-Net: A Model To Manage Service-Based Business Process Authorization, Haiyang Sun, Jian Yang, Weiliang Zhao, Sanjay K. Nepal

Faculty of Engineering - Papers (Archive)

Business process (BP) can be supported by a large number of resources with evolving contents. In order to receive the support from these resources, the BP must satisfy the authorization policies of these resources. On the other hand, a BP also has its own authorization policies that users must satisfy in order to interact with the BP. Meanwhile, execution policies need to be applied to manage the sequence of tasks invocations in a BP. Therefore, without proper coordination among these policies, BP may not be able to perform correctly, e.g., imperative support from a specific resource could be missing or …

Stress-Strain Model For Concrete Under Cyclic Loading, Farhad Aslani, Raha Jowkarmeimandi

Faculty of Engineering - Papers (Archive)

A hysteretic stress-strain model is developed for unconfined concrete with the intention of providing efficient modelling for the structural behaviour of concrete in seismic regions. The proposed model is based on the findings of previous experimental and analytical studies. The model for concrete subjected to monotonic and cyclic loading comprises four components in compression and tension - an envelope curve (for monotonic and cyclic loading), an unloading curve, a reloading curve and a transition curve. Formulations for partial unloading and partial reloading curves are also presented. The reliability of the proposed constitutive model is investigated for a reinforced concrete member …

Mechanics Of Design And Model Development Of Cvc-Plus Roll Curve, Jianzhong Xu, Dianyao Gong, Zhengyi Jiang, Xianghua Liu, Guodong Wang

Faculty of Engineering and Information Sciences - Papers: Part A

The mathematic model of CVC-Plus work roll curve is built. The ratio of the initial shifting value to the target crown is determined, and the mathematical model considering the relationship between the coefficients A2, A3, A4, A5 and is established. According to the theoretical analysis, the distance between the maximum or minimum point of the high order equivalent crown for work roll with CVC-plus roll curve and the rolling central point is the times of the roll barrel length. In general, the initial shifting value of the CVC-plus roll curve is not equal to the initial shifting value of the …

Integrated Seat And Suspension Control For A Quarter Car With Driver Model, Haiping Du, Weihua Li, Nong Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, an integrated vehicle seat and sus pension control strategy for a quarter car with driver model is proposed to improve suspension performance on driver ride comfort. An integrated seat and suspension model that includes a quarter-car suspension, a seat suspension, and a 4-degree-of freedom (DOM) driver body model is presented first. This in1 tegrated model provides a platform to evaluate ride comfort 1performance in terms of driver head acceleration responses under typical road disturbances and to develop an integrated control of seat and car suspensions. Based on the integrated model, an H∞ state feedback controller is designed …