Digital Commons Network^™

Simulation And Fabrication Of Three Novel Micromechanical Sensors, Yanqing Lu

Doctoral Dissertations

This work focuses on the simulation, fabrication and characterization of novel microdevices for chemical and biological sensors for improved sensitivity, enhanced performance and applicability. Specifically, microbridge and microcoil sensors have been fabricated via advanced microfabrication technologies. Due to the potential application in chemical and biological sensing, the growth of gold and platinum nanowires during an electrolysis process have also been investigated.

A microbridge can be considered as the head-to-head fusion of two cantilevers and the middle of the bridge would deform in a way similar to a microcantilever. The microbridge sensing device is more stable than the microcantilever, especially in …

Computer-Based Instruction For Engineering Education In The Developing World, Bradford G. Singley

Theses and Dissertations

Although civil engineers continually develop new ways to solve problems involving water, energy, infrastructure and environmental sustainability, these innovations can take years – or even decades – to reach developing countries. Computer-based instruction has the potential to dramatically decrease this lag time by improving engineering education in the developing world. This paper discusses the development of instructional simulations, based on the theory of model-centered instruction. These simulations can serve as self-paced learning modules, which can be accessed for free over the Internet. A pilot learning module was developed for the United Nations Educational Scientific and Cultural Organization (UNESCO) on the …

Steer It And Clear It: Effectiveness Of Quick Clearance Legislation, Amy Carol Hamlin

All Theses

Innovative incident management strategies have been sought by transportation professionals to minimize the impacts of incidents on traffic operation and safety. Some current quick clearance strategies such as 'Steer It and Clear It' legislation in South Carolina, which requires driver(s) of involved vehicle(s) in a minor incident to move vehicles promptly from the traveled roadway prior to the arrival of the first responders, can potentially reduce the duration of an incident. The research detailed in this paper endeavored to measure the benefit of the Steer It and Clear It law on a section of I-85 in South Carolina. A simulation …

A New Method For Treating Wells In Reservoir Simulation, Gregory M. Gessel

Theses and Dissertations

A new method for formulating finite difference equations for reservoir simulation has been developed. It can be applied throughout the entire simulated reservoir or to local segments. When applied to cells containing vertical, fully penetrating, straight-line wells in a homogeneous reservoir, the resulting equations are equivalent to Peaceman's classical well equations used in most reservoir simulators today. However, when the new finite difference equations are applied to both the well-containing cells, and their neighbors, the accuracy of the simulation improves substantially. The method produces still better accuracy results when applied throughout the reservoir. Unlike the Peaceman correction, the new method …

Gate Level Dynamic Energy Estimation In Asynchronous Circuits Using Petri Nets, Ryan Mabry

USF Tampa Graduate Theses and Dissertations

This thesis introduces a new methodology for energy estimation in asynchronous circuits. Unlike existing probabilistic methods, this is the first simulative work for energy estimation in all types of asynchronous circuits.

The new simulative methodology is based on Petri net modeling. A real delay model is incorporated to capture both gate delays and interconnect delays. The switching activity at each gate is captured to measure the average dynamic energy consumed per request/acknowledge handshaking pair. The new type of Petri net is called Hierarchical Colored Asynchronous Hardware Petri net (HCAHPN). The HCAHPN is able to capture the temporal and spatial correlations …

Comparison Of Simulated And Measured Flow Patterns: Solid And Gas Mixing In A 2d Turbulent Fluidized Bed, Ulla Ojaniemi, Sirpa Kallio, Alf Hermanson, Mikko Manninen, Maiju Seppälä, Veikko Taivassalo

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

Results from experiments done in a 2D turbulent fluidized bed cold model are presented. Experiments were conducted to study flow patterns, particle mixing in the bed and spreading of gas blown from one side into the bed. 2D simulations of the experiments were carried out using the Eulerian multiphase models of the Fluent and MFIX CFD softwares.

Numerical Simulation Of Spouted Bed Reactors Using Process Engineering Models: Application To Coal Gasification, Alexandra Mendes, Alain Dollet, Carine Ablitzer, Gilles Flamant, Christophe Perrais

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

A spouted bed reactor operating at high temperature has been modelled using one dimensional models based on process engineering concepts. The process of coal gasification has been selected to demonstrate the models achievements and predictions have been compared to previous spouted bed reactor experimental results.

Network Performance Management Using Application-Centric Key Performance Indicators, Susan Mcgill

Electronic Theses and Dissertations

The Internet and intranets are viewed as capable of supplying "Anything, Anywhere, Anytime" and e-commerce, e-government, e-community, and military C4I are now deploying many and varied applications to serve their needs. Network management is currently centralized in operations centers. To assure customer satisfaction with the network performance they typically plan, configure and monitor the network devices to insure an excess of bandwidth, that is overprovision. If this proves uneconomical or if complex and poorly understood interactions of equipment, protocols and application traffic degrade performance creating customer dissatisfaction, another more application-centric, way of managing the network will be needed. This research …

Assessment Of The Contribution Of Game-Based Simulation In The Advancement Of Individual Soldier Intelligence Gathering Skills, Carlos Wiley

Electronic Theses and Dissertations

Self-directed Learning Internet Modules based on gaming technology are making tremendous strides as tools to current training system for our military services. Currently, the US Army is testing the Every Soldier is a Sensor Simulation software (ES3) as part of the Every Soldiers a Sensor program that focuses on intelligence gathering and maintaining situational awareness. The primary training goal of this simulation is the training of individual soldiers on conducting "Active Surveillance" and "Threat Indicator Identification" where the soldier is an active participant in the process. Traditional training in intelligence gathering is based largely on cold war models. As a …

Details And Description Of Operations Research, Paul Savory

Industrial and Management Systems Engineering: Reports

The ambiguous term operations research was coined during World War II. A frequent substitute is management science. Operations research is a scientific approach to analyzing problems and making decisions. It uses mathematics and mathematical modeling on computers to forecast the implications of various choices and zero in on the best alternatives. This content paper provides an overview of operations research. It highlights operations research problems, methods for solving problems, different areas of operations research, and example problems.

Simulation Of Dynamic Recrystallization Using Irregular Cellular Automata, N Yazdipour, A Dehghan-Manshadi, C H. J Davies, P D. Hodgson

Faculty of Engineering - Papers (Archive)

Computer simulation is a powerful tool to predict microstructure and its evolution during dynamic recrystallization. Cellular Automata (CA), as one of the most efficient methods proposed to simulate recrystallization and grain growth. In this work, recrystallization and grain growth phenomena were modelled by using a two dimensional irregular CA method. Initial grain size, nuclei density and orientation of each grain were variables which have been used as entering data to the CA model. Final grain size, orientation of each grain, dislocation density and stress-strain curve were the results which have been resulted to validate the current model. Considering the model …

Dynamic Construction Visualizer, Purdue Ect Team

ECT Fact Sheets

The Dynamic Construction Visualizer (DCV) is general-purpose 3D visualization system that allows simulation model developers to animate modeled operations with chronological and spatial accuracy in 3D virtual space. The system is independent of any particular simulation-modeling program or CAD modeling software.

Stroboscope, Purdue Ect Team

ECT Fact Sheets

STROBOSCOPE is an acronym for STate and Resource Based Simulation of COnstructionProcEsses. It is a general-purpose simulation programming language that has been designed for the simulation of very complex construction processes that involve many different types of resources. STROBOSCOPE models are based on a network of interconnected modeling elements and on a series of programming statements that give the elements unique behavior and control the simulation.

The Simulation Of Magnetorheological Elastomers Adaptive Tuned Dynamic Vibration Absorber For Automobile Engine Vibration Control, X.C Zhang, X.Z. Zhang, W.H. Li, B. Liu, X.L. Gong, P.Q Zhang

Faculty of Engineering - Papers (Archive)

The aim of this article is to investigate the use of a Dynamic Vibration Absorber to control vibration of engine by using simulation. Traditional means of vibration control have involved the use of passive and more recently, active methods. This study is different in that it involves an adaptive component in the design of vibration absorber using magnetorheological elastomers (MREs) as the adaptive spring.

MREs are kind of novel smart material whose shear modulus can be controlled by applied magnetic field. In this paper, the vibration mode of a simple model of automobile engine is simulated by Finite Element Method …

Prosidyc: Simulation Program For Construction Operations, Purdue Ect Team

ECT Fact Sheets

PROSIDYC is a system for simulating construction operations jointly developed by the Planning and Methods Unit of Dragados y Construcciones, Madrid, Spain and the Division of Construction Engineering & Management at Purdue University. PROject SImulation Dragados Y Construcciones (PROSIDYC) is a computer based system for analyzing construction job site production processes. It is used to improve productivity in the field by studying resource utilization and cycle times and identifying opportunities for production improvement. PROSIDYC uses the CYCLic Operations NEtwork (CYCLONE) modeling format originally developed by Daniel W. Halpin

Virtualstep: 4d Simulation, Purdue Ect Team

ECT Fact Sheets

The main value from 4D is derived from using it proactively to visualize the construction sequence. Another benefit is the ability to run what-if scenarios to determine optimum scheduling and resource management. Also, by linking 3D drawings to a project schedule, all project stakeholders, from the owner to the tiling subcontractor, can see how the project is supposed to progress. VirtualSTEP Products include 4D Project Navigator, Conflict Coordinator, Project Reporter, and Project Analyzer. All these products are web-based.

Frequency-Domain Measurement Method For The Analysis Of Esd Generators And Coupling, Jayong Koo, Qing Cai, Giorgi Muchaidze, Andrew Martwick, Kai Wang, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

A method for analyzing electrostatic discharge (ESD) generators and coupling to equipment under test in the frequency domain is proposed. In ESD generators, the pulses are excited by the voltage collapse across relay contacts. The voltage collapse is replaced by one port of a vector network analyer (VNA). All the discrete and structural elements that form the ESD current pulse and the transient fields are excited by the VNA as if they were excited by the voltage collapse. In such a way, the method allows analyzing the current and field-driven linear coupling without having to discharge an ESD generator, eliminating …

Signal Processing Of An Ecg Signal In The Presence Of A Strong Static Magnetic Field, Aditya Gupta

Electronic Theses and Dissertations

This dissertation addresses the problem of elevation of the T wave of an electrocardiogram (ECG) signal in the magnetic resonance imaging (MRI). In the MRI, due to the strong static magnetic field the interaction of the blood flow with this strong magnetic field induces a voltage in the body. This voltage appears as a superimposition at the locus of the T wave of the ECG signal. This looses important information required by the doctors to interpret the ST segment of the ECG and detect diseases such as myocardial infarction. This dissertation aims at finding a solution to the problem of …

Modeling And Simulation Of A Microturbine Generator To Be Coupled With A Molten Carbonate Fuel Cell For Distributed Generation, Karleine M. Justice

Browse all Theses and Dissertations

Distributed generation is desired when the individual energy requirements ranging from 25-75 kW of office buildings, restaurants, hospitals and apartments can not be met by the current electric utility grid. Microturbine generators as stand alone power generation systems have been designed to meet these requirements. For power requirements up to 50 MW, hybrid fuel cell systems offer higher efficiency and lower levels of pollutant emissions with more advanced fuel energy savings than non-hybrid systems. The objective of this project is to develop a simulation of a microturbine generator as a stand alone power generation system to validate a microturbine generator …

Simulation Study Of Quadrupole Dielectrophoretic Trapping, Weihua Li, J Sun, B Liu, X Z. Zhang

Faculty of Engineering - Papers (Archive)

This paper presents a numerical study of particle trapping using quadrupole microfludic dielectrophoretic device. By taking into account the dielectrophoreis, viscous drag, the trajectory of particles flowing through the quadrupole device was obtained. Simulation results show that the device is effective for negative trapping, where particles are effectively trapped at the device centre. The device geometry is optimized by maximizing the dielectrophoretic force.

Fault Diagnosis In Multi-Station Assembly Systems Using An Agent-Based Simulation Model, Nagesh Shukla, Manoj Tiwari, Darek Ceglarek

Faculty of Engineering - Papers (Archive)

Today’s automotive industries require quick ramp-up in order to shorten the time to market and fulfill greater demand for product variety. Since, dimensional tolerance problems are one of the main causes for delay during ramp-up in multi-station assembly systems; hence, rapid diagnosis of faults contributing to dimensional errors is of significant concern. This paper presents an agent-based simulation model (ABSM) which integrates model-based and data-based diagnostics for fault diagnosis and correction in multi-station assembly processes. The fault causing variation sources, their effects on dimensional accuracy, diagnosis from sensors data and corrective actions in multi-station assembly systems are simulated using proposed …

Numerical Simulation Of Pile Group Behaviour In Liquefying Sloping Ground, Deepa S. Liyanapathirana

Faculty of Engineering - Papers (Archive)

This paper investigates pile group behaviour in liquefying sloping ground. The numerical procedure utilised involves two main steps. First a ground response analysis is carried out using a stress path model to obtain the maximum ground displacements along the pile and the degraded soil modulus over the depth of the soil deposit. Next a dynamic analysis is carried out for a single pile in the group assuming that each pile in the group behaves in the same way during the earthquake loading. The method has been verified using centrifuge data, where soil liquefaction has been observed in laterally spreading sloping …

Numerical Simulation Of Temperature Field And Thermal Stress Field Of Work Roll During Hot Strip Rolling, Chang-Sheng Li, Hai-Liang Yu, Guan-Yu Deng, Xiang-Hua Liu, Guo-Dong Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Based on the thermal conduction equations, the three-dimensional (3D) temperature field of a work roll was investigated using finite element method (FEM). The variations in the surface temperature of the work roll during hot strip rolling were described, and the thermal stress field of the work roll was also analyzed. The results showed that the highest roll surface temperature is 593 °C, and the difference between the minimum and maximum values of thermal stress of the work roll surface is 145. 7 MPa. Furthermore, the results of this analysis indicate that temperature and thermal stress are useful parameters for the …

Design Of A Controller To Control Light Level In A Commercial Office, Saeid Javidbakht

Browse all Theses and Dissertations

Proper amount of light in a business office is important for health and productivity of the employees. On a sunny day, there may be more than enough light entering the office from outside to carry out the necessary tasks. Presently, the main source of light in most offices is the fluorescent lamp. Thus, It is possible to save energy by dimming the fluorescent lamp. Dimming of the fluorescent lamp is possible by changing the frequency of the sinusoidal voltage or current. Hence, there is a need of a control system to adjust the light from the fixtures based on the …