Digital Commons Network^™

Introduction Of Iowa System Of Curves To Reliability Engineers, Alamgir Alvi

Masters Theses

The reliability engineers have been using different techniques and a good number of theoretical models to analyze and predict the performance of the designed systems and products. While, most of the engineers working in the area of life analysis, have been using the empirical model named Iowa systems of curves to analyze and forecast the service life of industrial properties. Two different groups of experts have obviously been working toward almost the same objective but using different techniques and tools. The purpose of this study is to introduce to reliability engineers the Iowa systems of curves and compare this empirical …

Experimental Investigation Of Water Spray Cooling Characteristics Of A Solid Heated Surface, Rainer F. Ponzel

Masters Theses

Water spray cooling characteristics of a solid heated surface were investigated to better understand the physical phenomenon of nucleate boiling heat transfer for full cone sprays. An experimental test loop was developed to conduct the spray cooling experiments. A uniform heat flux condition was assumed, and the liquid flow rate and nozzle orifice diameter were selected as the main variables. Two water temperatures were chosen to perform the study. Saturated water spray was utilized to measure the wall superheat temperature. Subcooled water spray was applied to investigate the effect of water spray in the single-phase regime.

Experiments conducted using the …

Flow Due To A Moving Pressure Distribution Over Free-Surface With Finite-Depth Bottom, Noriaki Okita

Masters Theses

Two-dimensional, steady-state and time-dependent analysis of wave making phenomenon due to a moving pressure distribution in sub-critical Froude number was performed. The domain is consisted of undisturbed free-surface at y=0, flat bottom at y=-h, and it is unbounded in horizontal direction. The pressure distribution was treated as an ideal model of an air-cushioned-vehicle (ACV). Ideal flow theory and linearized boundary conditions were used. Numerical integration algorithm was developed to evaluate the analytical solution. The surface elevation, bottom pressure profiles, and wave resistance were analyzed as functions of speed and depth.

The steady-state wave resistance calculated from the surface elevation profile …

Design And Development Of A User Interface Between Mapics/Db And Factor 5.2, Raghu Pothuri

Masters Theses

An interface program was designed to transfer production data from MAPICS/DB, a MRP II software, to FACTOR 5.2, a Finite Capacity Scheduling software. Since FACTOR 5.2 is designed to be used in a stand-alone mode with its own independent data base, this interface program extracts data from the MRP II System and converts it to formats specified by the Scheduling System. To create a computer model of the manufacturing process, information about manufacturing orders, routings, and production facilities was obtained from MAPICS/DB files. Certain information needed by FACTOR 5.2, which is not available in MAPICS/DB, was supplemented by the program …

Fuzzy Based Forebody Vortex Flow Controller For The X-29a Aircraft, Jin Suzuki

Masters Theses

This paper demonstrates the development and performance of A Fuzzy Logic based regulator for an aircraft which is equipped with pneumatic forebody Vortex Flow Controller at high angle-of-attack flight condition. The VFC provides the pilot additional control power at flight conditions where conventional effectors such as rudder and differential flaps lose effectiveness.

Fuzzy Logic Control (FLC) is applied to a mixed bang-bang and conventional type control system. This unique configuration ensures robustness of the system and simplifies the controller design. Performance of the FLC based regulator shows a 10.3% reduction in cost function compared to the system controlled by a …

Evolutionary Codesign, Karthikeyan Ethirajan

Masters Theses

We present our approach to hardware/software partitioning for embedded systems based upon Evolutionary Algorithms. We have implemented it in a CAD tool, EvoC - Evolutionary Codesign which does automatic hardware/software partitioning of real-time embedded systems at the system level. Our objective is to find good design configurations that are tuned towards user's preferences. We are able to explore a large, often intractable design space using Evolutionary Algorithms while evaluating solutions having multiple and sometimes conflicting attributes in the light of Multi-Attribute Utility Theory. EvoC provides a generic format for specifying a wide variety of design problems and the implementation assumes …

Predicting Timing Behavior In Architectural Design Exploration Of Real-Time Embedded Systems, Rajeshkumar Sambandam

Masters Theses

This thesis aims at developing efficient analytical techniques to perform trade-off studies in the architectural design exploration phase of real-time embedded systems. Real-time embedded systems (RTES) have stringent timing requirements. In the process of designing such a system, a key issue is to determine if a system is able to meet all the timing requirements imposed on it, though it may prove attractive in terms of cost and performance. Traditional methods of using event-driven simulation for modern RTES are very time consuming and are not guaranteed to prove feasibility. Specifically, we identify a flexibility metric to compare various options in …