Publications by IORA

A Planner-Trader Decomposition for Multimarket Hydro Scheduling

Kilian Schindler, Napat Rujeerapaiboon, Daniel Kuhn, Wolfram Wiesemann

Peak/off-peak spreads on European electricity forward and spot markets are eroding due to the ongoing nuclear phaseout in Germany and the steady growth in photovoltaic capacity. The reduced profitability of peak/off-peak arbitrage forces hydropower producers to recover part of their original profitability on the reserve markets. We propose a…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Operations Research

A Planner-Trader Decomposition for Multimarket Hydro Scheduling

Kilian Schindler, Napat Rujeerapaiboon, Daniel Kuhn, Wolfram Wiesemann

Operations Research

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Buffer Times Between Scheduled Events in Resource Assignment Problem: A Conflict-Robust Perspective

Jinjia Huang, Chung-Piaw Teo, Fan Wang, Zhou Xu

Problem definition: In many resource scheduling problem for services with scheduled starting and com- pletion times (e.g., airport gate assignment), a common approach is to maintain appropriate buffer between successive services assigned to a common resource. With a large buffer, the chances of a “crossing” (i.e., a flight arriving…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Manufacturing & Service Operations Management

Buffer Times Between Scheduled Events in Resource Assignment Problem: A Conflict-Robust Perspective

Jinjia Huang, Chung-Piaw Teo, Fan Wang, Zhou Xu

Manufacturing & Service Operations Management

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Real-time cruising speed design approach for multiline bus systems

Bomin Bian, Ning Zhu, Qiang Meng

In this paper, we focus on controlling multiline buses operated in networks with curbside bus stops. In such networks, both bus bunching and bus queueing, which often result in passenger inconvenience as well as bus waiting delays, are frequently observed during bus operations. To address the adverse influences of…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Transportation Research Part B: Methodological

Real-time cruising speed design approach for multiline bus systems

Bomin Bian, Ning Zhu, Qiang Meng

Transportation Research Part B: Methodological

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Online Passenger Flow Control in Metro Lines

Jinpeng Liang, Guodong Lyu, Chung-Piaw Teo, Ziyou Gao

Crowd management during peak commuting hours is a key challenge facing oversaturated metro systems worldwide, which results in serious safety concerns and uneven service experience for commuters on different origin-destination (o-d) pairs. This paper develops real-time passenger flow control policies to manage the inflow of crowds at each station,…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Operations Research

Online Passenger Flow Control in Metro Lines

Jinpeng Liang, Guodong Lyu, Chung-Piaw Teo, Ziyou Gao

Operations Research

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Taming the Long Tail: The Gambler’s Fallacy in Intermittent Demand Management

Sheng Bi, Long He, Chung-Piaw Teo

Problem definition: “Long tail” products with intermittent demand often tie up valuable warehouse space and capital investment for many companies. Furthermore, the paucity of demand data poses additional challenges for model estimation and performance evaluation. Traditional inventory solutions are not designed for products with intermittent demand. In this paper,…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

MSOM

Taming the Long Tail: The Gambler’s Fallacy in Intermittent Demand Management

Sheng Bi, Long He, Chung-Piaw Teo

MSOM

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Vessel deployment with limited information: Distributionally robust chance constrained models

Yue Zhao, Zhi Chen, Andrew Lim, Zhenzhen Zhang

This paper studies the fundamental vessel deployment problem in the liner shipping industry, which decides the numbers of mixed-type ships and their sailing frequencies on fixed routes to provide sufficient vessel capacity for fulfilling stochastic shipping demands with high probability. In reality, it is usually difficult (if not impossible)…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Transportation Research Part B: methodological

Vessel deployment with limited information: Distributionally robust chance constrained models

Yue Zhao, Zhi Chen, Andrew Lim, Zhenzhen Zhang

Transportation Research Part B: methodological

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

A target-based optimization model for bike-sharing systems

Qingxin Chen, Chenyi Fu, Ning Zhu, Shoufeng Ma, Qiao-Chu He

The emergence of bike-sharing systems has considerably improved last- and first-mile transportation systems. To ensure attractiveness to end users, operators aim to design effective service-oriented operational strategies to meet the desired service targets for users. Most existing studies focus on the service efficiency of bike-sharing systems, while service equity…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Transportation Research Part B: Methodological

A target-based optimization model for bike-sharing systems

Qingxin Chen, Chenyi Fu, Ning Zhu, Shoufeng Ma, Qiao-Chu He

Transportation Research Part B: Methodological

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Bike-sharing inventory management for market expansion

Chenyi Fu, Ning Zhu, Shoufeng Ma, Qiao-Chu He, Hai Yang

Over the past two decades, bike-sharing systems have grown significantly worldwide. Compared with that of other business sectors, the means by which revenue is obtained in the bike-sharing industry is unique. When the market in a region or city is saturated, an efficient way for a firm to increase…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Transportation Research Part B: Methodological

Bike-sharing inventory management for market expansion

Chenyi Fu, Ning Zhu, Shoufeng Ma, Qiao-Chu He, Hai Yang

Transportation Research Part B: Methodological

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Dynamic Inventory Repositioning in On-Demand Rental Networks

Saif Benjaafar, Daniel Jiang, Xiang Li, Xiaobo Li

We consider a rental service with a fixed number of rental units distributed across multiple locations. The units are accessed by customers without prior reservation and on an on-demand basis. Customers can decide on how long to keep a unit and where to return it. Because of the randomness…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Management Science

Dynamic Inventory Repositioning in On-Demand Rental Networks

Saif Benjaafar, Daniel Jiang, Xiang Li, Xiaobo Li

Management Science

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Satisficing Models under Uncertainty

Patrick Jailet, Sanjay D. Jena, Adam TS Ng, Melvyn Sim

Satisficing, as an approach to decision making under uncertainty, aims at achieving solutions that satisfy the problem’s constraints as well as possible. Mathematical optimization problems that are related to this form of decision making include the P-model. In this paper, we propose a general framework of satisficing decision criteria…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

INFORMS Journal on Optimziation

Satisficing Models under Uncertainty

Patrick Jailet, Sanjay D. Jena, Adam TS Ng, Melvyn Sim

INFORMS Journal on Optimziation

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Robust pricing and production with information partitioning and adaptation

Georgia Perakis, Melvyn Sim, Qinshen Tang, Xiong Peng

We introduce a new distributionally robust optimization model to address a two-period, multiitem joint pricing and production problem, which can be implemented in a data-driven setting using historical demand and side information pertinent to the prediction of demands. Starting from an additive demand model, we introduce a new partitioned-moment-based…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Management Science

Robust pricing and production with information partitioning and adaptation

Georgia Perakis, Melvyn Sim, Qinshen Tang, Xiong Peng

Management Science

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Advance admission scheduling via resource satisficing

Minglong Zhou, Melvyn Sim, Shao-Wei Lam

We study the problem of advance scheduling of ward admission requests in a public hospital, which affects the usage of critical resources such as operating theaters and hospital beds. Given the stochastic arrivals of patients and their uncertain usage of resources, it is often infeasible for the planner to…

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

Production and Operations Management

Advance admission scheduling via resource satisficing

Minglong Zhou, Melvyn Sim, Shao-Wei Lam

Production and Operations Management

This research is supported by the Ministry of Education, Singapore, under its 2019 Academic Research Fund Tier 3 grant call (Award ref: MOE-2019-T3-1-010)

IORA

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