Southwest Wisconsin Technical College

About: Southwest Wisconsin Technical College is a education organization based out in Fennimore, Wisconsin, United States. It is known for research contribution in the topics: Microstructure & Alloy. The organization has 240 authors who have published 219 publications receiving 2667 citations. The organization is also known as: Southwest Tech.

Uncertainty analysis for computer model projections of hurricane losses.

Abstract: Projecting losses associated with hurricanes is a complex and difficult undertaking that is wrought with uncertainties. Hurricane Charley, which struck southwest Florida on August 13, 2004, illustrates the uncertainty of forecasting damages from these storms. Due to shifts in the track and the rapid intensification of the storm, real-time estimates grew from 2 to 3 billion dollars in losses late on August 12 to a peak of 50 billion dollars for a brief time as the storm appeared to be headed for the Tampa Bay area. The storm hit the resort areas of Charlotte Harbor near Punta Gorda and then went on to Orlando in the central part of the state, with early poststorm estimates converging on a damage estimate in the 28 to 31 billion dollars range. Comparable damage to central Florida had not been seen since Hurricane Donna in 1960. The Florida Commission on Hurricane Loss Projection Methodology (FCHLPM) has recognized the role of computer models in projecting losses from hurricanes. The FCHLPM established a professional team to perform onsite (confidential) audits of computer models developed by several different companies in the United States that seek to have their models approved for use in insurance rate filings in Florida. The team's members represent the fields of actuarial science, computer science, meteorology, statistics, and wind and structural engineering. An important part of the auditing process requires uncertainty and sensitivity analyses to be performed with the applicant's proprietary model. To influence future such analyses, an uncertainty and sensitivity analysis has been completed for loss projections arising from use of a Holland B parameter hurricane wind field model. Uncertainty analysis quantifies the expected percentage reduction in the uncertainty of wind speed and loss that is attributable to each of the input variables.

Microstructures and Mechanical Properties of In-Situ Al 3 Ti/2024 Aluminum Matrix Composites Fabricated by Ultrasonic Treatment and Subsequent Squeeze Casting

Abstract: Squeeze casting is a near net shaping technology which is advantageous to refining the microstructures and improving the mechanical properties. In the present work, in-situ Al3Ti/2024 Aluminum matrix composites with different amount of Al3Ti reinforcements were successfully fabricated by ultrasonic treatment and subsequent squeeze casting. The effects of specific pressure and the amount of reinforcements on microstructures and mechanical properties were studied. The results show that when the specific pressure is increased from 0 to 150 MPa, the average grain sizes of α-Al matrix are decreased by 39.8%, and the yield strength and compressive strength are increased by 16.8% and 22.9%, respectively. However, severe segregations of eutectic structures were generated under an excessive specific pressure of 200 MPa, which also results in deterioration in the mechanical strength. The mass fraction of Al3Ti phases has significant influence on morphology of eutectic structures. When the mass fraction of Al3Ti phases is increased from 4 to 16 wt%, the eutectic structures was changed from continuous network to dispersed structures gradually. The compressive strength was increased from 611.2 to 712.0 MPa (increased by 16.5%), as the Al3Ti content increasing from 0 to 16 wt%. However, as the mass fraction of Al3Ti phases increased, the variation in the yield strength is not monotonically increasing.