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Full-Text Articles in Engineering
Intelligent Simulation-Based Lot Scheduling Of Photolithography Toolsets In A Wafer Fabrication Facility, Amr Arisha, Paul Young
Intelligent Simulation-Based Lot Scheduling Of Photolithography Toolsets In A Wafer Fabrication Facility, Amr Arisha, Paul Young
Conference papers
Scheduling of a semiconductor manufacturing facility is one of the most complex tasks encountered. Confronted with a high technology product market, semiconductor manufacturing is increasingly more dynamic and competitive in the introduction of new products in shorter time intervals. Photolithography, being one of the processes repeated often, is a fabrication bottleneck. Lot scheduling within photolithography is a challenging activity where substantial improvements in factory performance can be made. The proposed scheduling methodology integrates two common approaches, simulation and artificial intelligence. Using detailed simulation modeling within a structured modeling method, a comprehensive model to characterize the photolithography process was developed. An …
A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Ashu Guru, Paul Savory
A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Ashu Guru, Paul Savory
Department of Industrial and Management Systems Engineering: Faculty Publications
Although simulation is one of the most innovative and cost-effective tools for modeling and analyzing a system, simulation studies often fail to provide any useful results. One reason is attributed to the fact that model formulation depends on the skills of the analyst. This paper describes a research to develop a conceptual modeling infrastructure to assist a simulation analyst in specifying components for studying physical security systems. The modeling framework has been programmed as an internet-based web application. Using the application, the successful development and implementation of a physical security simulation model will be aided by a defined scientific methodology …
Pre-Impact Lower Extremity Posture And Brake Pedal Force Predict Foot And Ankle Forces During An Automobile Collision, Elizabeth C. Hardin, Anne Su, Antonie J. Van Den Bogert
Pre-Impact Lower Extremity Posture And Brake Pedal Force Predict Foot And Ankle Forces During An Automobile Collision, Elizabeth C. Hardin, Anne Su, Antonie J. Van Den Bogert
Mechanical Engineering Faculty Publications
Background: The purpose of this study was to determine how a driver’s foot and ankle forces during a frontal vehicle collision depend on initial lower extremity posture and brake pedal force. Method of Approach: A 2D musculoskeletal model with seven segments and six right-side muscle groups was used. A simulation of a three-second braking task found 3647 sets of muscle activation levels that resulted in stable braking postures with realistic pedal force. These activation patterns were then used in impact simulations where vehicle deceleration was applied and driver movements and foot and ankle forces were simulated. Peak rearfoot ground reaction …
A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Paul Savory
A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Paul Savory
Department of Industrial and Management Systems Engineering: Faculty Publications
Although simulation is one of the most innovative and cost-effective tools for modeling and analyzing a system, simulation studies often fail to provide any useful results. One reason is attributed to the fact that model formulation depends on the skills of the analyst. This paper describes a research to develop a conceptual modeling infrastructure to assist a simulation analyst in specifying components for studying physical security systems. The modeling framework has been programmed as an internet-based web application. Using the application, the successful development and implementation of a physical security simulation model will be aided by a defined scientific methodology …
Modeling Yield Of Carbon-Nanotube/Silicon-Nanowire Fet-Based Nanoarray Architecture With H-Hot Addressing Scheme, Shanrui Zhang, Minsu Choi, Nohpill Park
Modeling Yield Of Carbon-Nanotube/Silicon-Nanowire Fet-Based Nanoarray Architecture With H-Hot Addressing Scheme, Shanrui Zhang, Minsu Choi, Nohpill Park
Electrical and Computer Engineering Faculty Research & Creative Works
With molecular-scale materials, devices and fabrication techniques recently being developed, high-density computing systems in the nanometer domain emerge. An array-based nanoarchitecture has been recently proposed based on nanowires such as carbon nanotubes (CNTs) and silicon nanowires (SiNWs). High-density nanoarray-based systems consisting of nanometer-scale elements are likely to have many imperfections; thus, defect-tolerance is considered one of the most significant challenges. In this paper we propose a probabilistic yield model for the array-based nanoarchitecture. The proposed yield model can be used (1) to accurately estimate the raw and net array densities, and (2) to design and optimize more defect and fault-tolerant …
An Extrapolation Procedure To Shorten Time Domain Simulations, Giuseppe Selli, James L. Drewniak, David Pommerenke
An Extrapolation Procedure To Shorten Time Domain Simulations, Giuseppe Selli, James L. Drewniak, David Pommerenke
Electrical and Computer Engineering Faculty Research & Creative Works
Time-domain simulation algorithms are widely used in the anaylsis and design of electromagnetic systems. Many of them are characterized by high Q's. Thus, the simulations have to employ many time steps in order to achieve a complete characterization of these systems. This time-consuming computational effort can be avoided if the late instants of time are extrapolated by applying a parametric estimation algorithm. An optimized implementation of a time-domain extrapolation method and a stop criterion are discussed in this paper. The latter criterion is based upon a normalized squared difference between the waveforms extrapolated from two different sets of initial data …
Foot And Ankle Forces During An Automobile Collision: The Influence Of Muscles, Elizabeth C. Hardin, Anne Su, Antonie J. Van Den Bogert
Foot And Ankle Forces During An Automobile Collision: The Influence Of Muscles, Elizabeth C. Hardin, Anne Su, Antonie J. Van Den Bogert
Mechanical Engineering Faculty Publications
Muscles have a potentially important effect on lower extremity injuries during an automobile collision. Computational modeling can be a powerful tool to predict these effects and develop protective interventions. Our purpose was to determine how muscles influence peak foot and ankle forces during an automobile collision. A 2-D bilateral musculoskeletal model was constructed with seven segments. Six muscle groups were included in the right lower extremity, each represented by a Hill muscle model. Vehicle deceleration data were applied as input and the resulting movements were simulated. Three models were evaluated: no muscles (NM), minimal muscle activation at a brake pedal …
Quantization With Knowledge Base Applied To Geometrical Nesting Problem, Grzegorz Chmaj, Leszek Koszalka
Quantization With Knowledge Base Applied To Geometrical Nesting Problem, Grzegorz Chmaj, Leszek Koszalka
Electrical & Computer Engineering Faculty Research
Nesting algorithms deal with placing two-dimensional shapes on the given canvas. In this paper a binary way of solving the nesting problem is proposed. Geometric shapes are quantized into binary form, which is used to operate on them. After finishing nesting they are converted back into original geometrical form. Investigations showed, that there is a big influence of quantization accuracy for the nesting effect. However, greater accuracy results with longer time of computation. The proposed knowledge base system is able to strongly reduce the computational time.
Geometric Modelling Of The Temporal Bone For Cochlea Implant Simulation, Catherine Todd, Fazel Naghdy, S. J. O'Leary
Geometric Modelling Of The Temporal Bone For Cochlea Implant Simulation, Catherine Todd, Fazel Naghdy, S. J. O'Leary
Faculty of Engineering - Papers (Archive)
The first stage in the development of a clinically valid surgical simulator for training otologic surgeons in performing cochlea implantation is presented. For this purpose, a geometric model of the temporal bone has been derived from a cadaver specimen using the biomedical image processing software package Analyze (AnalyzeDirect, Inc) and its three-dimensional reconstruction is examined. Simulator construction begins with registration and processing of a Computer Tomography (CT) medical image sequence. Important anatomical structures of the middle and inner ear are identified and segmented from each scan in a semi-automated threshold-based approach. Linear interpolation between image slices produces a three-dimensional volume …