An Algorithm for Crew Scheduling Problem with Bin Packing Features

An Algorithm for Crew Scheduling Problem with Bin Packing Features

Abstract :-
This thesis proposes a new approach for solving the traditional crew scheduling problem. The crew scheduling problem is solved with a bin packing approach in polynomial time. Based on the extensive research on the bin packing problem during the past 40 years, an algorithm that is proved to be the most efficient for solving most bin packing problems is selected and modified for application in the crew scheduling problem. Continue reading An Algorithm for Crew Scheduling Problem with Bin Packing Features

Air Express Network Design with Hub Sorting

Air Express Network Design with Hub Sorting

Abstract :-
This dissertation examines an innovative strategic operation for next day air package delivery. The proposed system, in which some packages are sorted twice at two distinct hubs before arriving at their destinations, is investigated for its potential savings. A two-stage sorting operation is proposed and compared to the currently operated single-stage sorting operation. Continue reading Air Express Network Design with Hub Sorting

An Agent-Based Model To Examine Housing Price, Household Location Choice And Commuting Times In Knox County, Tennessee

An Agent-Based Model To Examine Housing Price, Household Location Choice, And Commuting Times In Knox County, Tennessee

Abstract :-
The research conducted for this thesis uses an agent-based model (ABM) to simulate housing price, location, and journey to work (JTW) times for households in Knox County, Tennessee. The model is a unique hybrid, combining analytic functions and agents that typically have been used separately for theoretical urban research in very simplified urban landscapes. At the same time it uses data from a real urban area to run and calibrate the model, which is common for statistically-based or gravity models. Continue reading An Agent-Based Model To Examine Housing Price, Household Location Choice And Commuting Times In Knox County, Tennessee

Methods for Adjusting U.S. Geological Survey Rural Regression Peak Discharges in an Urban Setting

Methods for Adjusting U.S. Geological Survey Rural Regression Peak Discharges in an Urban Setting

Abstract :-
A study was conducted of 78 U.S. Geological Survey gaged streams that have been subjected to varying degrees of urbanization over the last three decades. Flood-frequency analysis coupled with nonlinear regression techniques were used to generate a set of equations for converting peak discharge estimates determined from rural regression equations to a set of peak discharge estimates that represent known urbanization. Specifically, urban regression equations for the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year return periods were calibrated as a function of the corresponding rural peak discharge and the percentage of impervious area in a watershed. The results of this study indicate that two sets of equations, one set based on imperviousness and one set based on population density, performed well. Both sets of equations are dependent on rural peak discharges, a measure of development (average percentage of imperviousness or average population density), and a measure of homogeneity of development within a watershed. Average imperviousness was readily determined by using geographic information system methods and commonly available land-cover data. Similarly, average population density was easily determined from census data. Thus, a key advantage to the equations developed in this study is that they do not require field measurements of watershed characteristics as did the U.S. Geological Survey urban equations developed in an earlier investigation. During this study, the U.S. Geological Survey PeakFQ program was used as an integral tool in the calibration of all equations. The scarcity of historical land-use data, however, made exclusive use of flow records necessary for the 30-year period from 1970 to 2000. Such relatively short-duration streamflow time series required a nonstandard treatment of the historical data function of the PeakFQ program in comparison to published guidelines. Thus, the approach used during this investigation does not fully comply with the guidelines set forth in U.S. Geological Survey Bulletin 17B, and modifications may be needed before it can be applied in practice.

Author:- Moglen, Glenn E., Schwartz, Dorianne E.

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