Open Access. Powered by Scholars. Published by Universities.®

Operations Research, Systems Engineering and Industrial Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Robust Multichannel Functional-Data-Analysis Methods For Data Recovery In Complex Systems, Jian Sun Dec 2011

Robust Multichannel Functional-Data-Analysis Methods For Data Recovery In Complex Systems, Jian Sun

Doctoral Dissertations

In recent years, Condition Monitoring (CM), which can be performed via several sensor channels, has been recognized as an effective paradigm for failure prevention of operational equipment or processes. However, the complexity caused by asynchronous data collection with different and/or time-varying sampling/transmission rates has long been a hindrance in the effective use of multichannel data in constructing empirical models. The problem becomes more challenging when sensor readings are incomplete. Traditional sensor data recovery techniques are often prohibited in asynchronous CM environments, not to mention sparse datasets. The proposed Functional Principal Component Analysis (FPCA) methodologies, e.g., nonparametric FPC ...


A Numerical Study Of Droplet Formation And Behavior Using Interface Tracking Methods, Sandeep Menon Sep 2011

A Numerical Study Of Droplet Formation And Behavior Using Interface Tracking Methods, Sandeep Menon

Open Access Dissertations

An adaptive remeshing algorithm has been developed for multiphase flow simulations using the moving-mesh interface tracking (MMIT) technique. The edge-swapping algorithm uses the Delaunay criterion (in 2D) and a dynamic programming technique (in 3D) to maximize the quality of mesh primitives surrounding edges in the mesh, and performs local remeshing to minimize interpolation errors. Edge bisection and contraction operations are also performed to adjust the mesh resolution around important features like fluid-interfaces, driven by a local length scale estimation algorithm that is efficient and easily parallelized. Flow-field interpolation after reconnection is achieved using a conservative, second-order accurate remapping scheme that ...


High-Resolution, Non-Contact Angular Measurement System For Psa/Rsa, Ronald D. Sloat Mar 2011

High-Resolution, Non-Contact Angular Measurement System For Psa/Rsa, Ronald D. Sloat

Master's Theses and Project Reports

A non-contact angular measurement system for Pitch Static Attitude (PSA) and Roll Static Attitude (RSA) of hard disk drive sliders is designed and built. Real-time sampling at over 15 KHz is achieved with accuracy of +/- 0.05 degrees over a range of approximately 2-3 degrees. Measuring the PSA and RSA is critical for hard drive manufacturers to control and improve the quality and reliability of hard drives. Although the hard drive industry is able to measure the PSA and RSA at the subassembly level at this time, there is no system available that is able to measure PSA/RSA at ...


Benefits Of Cpfr And Vmi Collaboration Strategies In A Variable Demand Environment, Dattaraj Kamalapurkar Jan 2011

Benefits Of Cpfr And Vmi Collaboration Strategies In A Variable Demand Environment, Dattaraj Kamalapurkar

Dissertations

In recent years, practitioners and academic researchers have emphasized that organizations need to collaborate with suppliers and customers to improve their competitive advantage. The availability of cost efficient information technologies like EDI, XML, etc. have made it possible to develop and implement many forms of collaboration strategies. Among them, Vendor Managed Inventory (VMI) and Collaborative Planning, Forecasting and Replenishment (CPFR) are most popular, which are considered for this study. While many studies have identified the benefits of demand information sharing in supply chains; however the benefits gained by implementing collaboration strategies like VMI and CPFR in a variable demand environment ...