Optimal maintenance scheduling of a gas engine power plant using generalized disjunctive programming

A new continuous-time model for long-term scheduling of a gas engine power plant with parallel units is presented. Gas engines are shut down according to a regular maintenance plan that limits the number of hours spent online. To minimize salary expenditure with skilled labor, a single maintenance team is considered which is unavailable during certain periods of time. Other challenging constraints involve constant minimum and variable maximum power demands. The objective is to maximize the revenue from electricity sales assuming seasonal variations in electricity pricing by reducing idle times and shutdowns in high-tariff periods. By first developing a generalized disjunctive programming model and then applying both big-M and hull reformulation techniques, we reduce the burden of finding the appropriate set of mixed-integer linear constraints. Through the solution of a real-life problem, we show that the proposed formulations are very efficient computationally, while gaining valuable insights about the system

Sensor Systems in the Transportation Industry (Spring 2001) IPRO 353

The prototypes for a railroad tank car monitoring system have been developed in prior IPRO projects. The prototypes now need to be developed into potential product form, beta tested, and evaluated both technically and from a market perspective. A patent application has been outlined. A business plan needs to be written that gathers the information required to decide on a commercial product offering to Union Tank Car as the first customer. A market survey should define the potential market within the railroad industry, the economics of such a business, and its potential in other related market segments, such as trucking. At the end of this Entrepreneurial IPRO, we should have beta tested the potential product. If the results are successful, manufacturers and suppliers should be identified to bring the product to market. A first sale offering should be made to Union Tank Car, assuming beta testing is successful. The possibility to formulate a successful business together with our first customer, Union Tank Car, will be evaluated. The team required to execute the business plan will be identified; and the.potential for financing will also be addressed. This entrepreneurial team would ideally consist of chemistry and chemical engineering students for sensor development work; mechanical and electrical engineering students for product engineering and production setup; business school and law school students to support business plan development, market analysis and patenting for the business.Sponsorship: Union Tank Car Company, a member of The Marmon Group of companies.Project Plan for IPRO 353: Sensor Systems in the Transportation Industry for the Spring 2001 semeste

ZrO2- and Li2ZrO3-stabilized spinel and layered electrodes for lithium batteries

Strategies for countering the solubility of LiMn2O4 (spinel) electrodes at 50 °C and for suppressing the reactivity of layered LiMO2 (M=Co, Ni, Mn, Li) electrodes at high potentials are discussed. Surface treatment of LiMn2O4 with colloidal zirconia (ZrO2) dramatically improves the cycling stability of the spinel electrode at 50 °C in Li/LiMn2O4 cells. ZrO2-coated LiMn0.5Ni0.5O2 electrodes provide a superior capacity and cycling stability to uncoated electrodes when charged to a high potential (4.6 V vs Li0). The use of Li2ZrO3, which is structurally more compatible with spinel and layered electrodes than ZrO2 and which can act as a Li+-ion conductor, has been evaluated in composite 0.03Li2ZrO3·0.97LiMn0.5Ni0.5O2 electrodes; glassy LixZrO2+x/2 (0<x⩽2) products can be produced from colloidal ZrO2 for surface coatings. Keywords: Lithium batteries, Stabilized electrode, Spinel, Layered, Zirconia, Coatin