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Design for Process Flexibility: Efficiency of the Long Chain and Sparse Structure
tl;dr
The concept of chaining, or in more general terms, sparse process structure, has been extremely influential in the process flexibility area, with many large automakers already making this the cornerstone of their business strategies to remain competitive. Expand
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  • Open Access
Models and Insights for Hospital Inpatient Operations: Time-Dependent ED Boarding Time
tl;dr
We propose a novel stochastic processing network with the following characteristics to model the dynamics of inpatient flow with a particular focus on predicting the time-of-day waiting time performance during the process of transferring from the ED to wards and identifying strategies (from the inpatient side) to reduce the waiting. Expand
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  • Open Access
Process Flexibility Revisited: The Graph Expander and Its Applications
tl;dr
We analyze in this paper the worst-case performance of the flexible structure design problem under a more general setting, which encompasses a large class of objective functions. Expand
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  • Open Access
Models for Effective Deployment and Redistribution of Bicycles Within Public Bicycle-Sharing Systems
tl;dr
We develop a network flow model with proportionality constraints to estimate the flow of bicycles within the network and the number of trips supported, given an initial allocation of bicycles at each station. Expand
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  • Open Access
The asymptotic performance ratio of an on-line algorithm for uniform parallel machine scheduling with release dates
tl;dr
The Weighted Shortest Processing Requirement (WSPR) heuristic is a simple extension of the well known WSPT heuristic, which is optimal for the single machine problem without release dates. Expand
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On range and response: Dimensions of process flexibility
tl;dr
We model the response dimension in terms of uniformity of production cost. Expand
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Hospital Inpatient Operations : Mathematical Models and Managerial Insights
One key factor contributing to the emergency department (ED) overcrowding is prolonged waiting time for admission to inpatient wards, also known as ED boarding time. To gain insights into theExpand
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  • Open Access
On the Asymptotic Optimality of a Simple On-Line Algorithm for the Stochastic Single-Machine Weighted Completion Time Problem and Its Extensions
tl;dr
We analyze the performance of the on-line nonpreemptive weighted shortest expected processing time among available jobs (WSEPTA) heuristic for the stochastic single-machine problem, when the objective is to minimize the expected total weighted completion time of a set of jobs that are released over time. Expand
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Stowage planning for container ships: A heuristic algorithm to reduce the number of shifts
tl;dr
We consider the stowage planning problem of a container ship, where the ship visits a series of ports sequentially and containers can only be accessed from the top of stacks. Expand
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Patient Flow from Emergency Department to Inpatient Wards: Empirical Observations from a Singaporean Hospital
This document presents a comprehensive empirical study on the inpatient flow management in a Singaporean hospital. The empirical study uses high resolution patient flow data from 2008 to 2010. ThisExpand
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  • Open Access