Article
Transportation Science & Technology
Homero Larrain, Hemant K. Suman, Juan Carlos Munoz
Summary: This work introduces a new route-based equilibrium assignment formulation and algorithm for congested transit networks, overcoming three key challenges in the process.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2021)
Article
Economics
Qingyun Tian, David Z. W. Wang, Yun Hui Lin
Summary: This paper focuses on a transit service operation design problem that determines the optimal frequency settings with explicit consideration of congested common lines in a bus service network. A trilevel programming approach is applied, optimizing transit frequency, passengers' transit routing choices, and equilibrium strategies in common line problems. Solution methods include transforming the model into a mixed-integer linear program and using a surrogate optimization approach for efficiency. Extensive numerical examples validate the model and proposed solution algorithms.
TRANSPORTATION RESEARCH PART B-METHODOLOGICAL
(2021)
Article
Transportation Science & Technology
Jiemin Xie, Shuguang Zhan, S. C. Wong, S. M. Lo
Summary: This study proposes a model and method for solving the transit timetabling problem by considering passenger path choices, generating timetables based on passenger-equilibrium assignment results to improve passenger experience efficiently.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2021)
Article
Mathematics, Interdisciplinary Applications
Kai Lu, Nan Cao
Summary: This paper introduces the application of the optimal strategy model in transit network, which can better demonstrate the flexibility of passengers. A simulation-based algorithm considering capacity constraints is proposed and applied to the Beijing Subway to demonstrate the feasibility of the model.
Article
Transportation Science & Technology
Mohammad Hadi Mansourianfar, Ziyuan Gu, S. Travis Waller, Meead Saberi
Summary: The paper proposes a joint routing and pricing control scheme to incentivize CAVs to seek system-optimal routing, reducing total system travel time and discouraging congestion by human-driven vehicles in city centers.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2021)
Article
Chemistry, Physical
Mauricio J. del Razo, Manuel Dibak, Christof Schuette, Frank Noe
Summary: A novel approach, MSM/RD, is developed to simulate protein-ligand systems at large time and length scales by coupling Markov state models of molecular kinetics with particle-based reaction-diffusion simulations. The framework is capable of modeling protein-protein interactions and handling multiple molecules, addressing limitations such as isotropic ligands and single conformational states. The code has been published for reproducibility.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Computer Science, Information Systems
Mahmoud Owais, Abdou S. Ahmed
Summary: In this study, two well-known graphical transit assignment models are comprehensively reviewed and formulated in a single mathematical notation framework for the first time, aiming to better understand their inherent differences. These considered models are deficient in their basic assumptions compared to the most used transit assignment models in TNDP, highlighting the need for renewed attention.
Article
Management
Guoyuan Li, Anthony Chen
Summary: This paper proposes a strategy-based transit stochastic user equilibrium (SUE) model that considers capacity and number-of-transfers constraints in an urban congested transit network. The model uses a route-section-based method for network representation and assumes passengers' route choice behavior obeys the logit model. The transit line capacity and maximum number-of-transfers constraints are considered, and the problem is formulated as a variational inequality (VI) problem. A transit path-set generation procedure is proposed, and the asymmetric cost function is solved using the diagonalization method.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2023)
Article
Chemistry, Physical
Ying Zhang, Samuel A. Isaacson
Summary: In particle-based stochastic reaction-diffusion models, the choice of reaction rates and placement kernels is crucial for determining the occurrence probability and location of reactions. This study presents a general partial-integral differential equation model that encompasses common particle models, and derives a detailed balance condition for reversible reactions. It also discusses the requirement for spatially varying unbinding rate functions near the domain boundary in order to maintain detailed balance of spatial reaction fluxes.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Transportation Science & Technology
Mohammad Hadi Mansourianfar, Ziyuan Gu, Meead Saberi
Summary: This study aims to develop a timedependent optimal ratio control scheme (TORCS) to achieve system optimum routing for AVs in urban networks, while striking a reasonable balance between total travel time savings and control costs. The research introduces a new concept of frequency control within the TORCS application, enabling the central agent to control the route choice of selected AVs only during time periods with the most significant impact on system travel time reduction.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2022)
Article
Transportation
Jiahua Zhang, Kentaro Wada, Takashi Oguchi
Summary: This paper proposes a macroscopic model to describe the equilibrium distribution of passenger arrivals for the morning commute problem in a congested urban rail transit system. The proposed model uses a macroscopic train operation sub-model to simplify the interaction between passengers and trains while maintaining their essential physical relations. The equilibrium conditions and solution method of the model are derived and the characteristics of the equilibrium are examined analytically and numerically. An application of the model is presented to analyze a time-dependent timetable optimization problem with equilibrium constraints, revealing a 'capacity increasing paradox' and evaluating the influence of timetable design on passengers' equilibrium travel costs.
TRANSPORTMETRICA B-TRANSPORT DYNAMICS
(2023)
Article
Operations Research & Management Science
Robert Aboolian, Oded Berman, Majid Karimi
Summary: This paper discusses the design of a facility network with the goal of minimizing overall costs while taking congestion into account. The problem is formulated as a nonlinear mixed-integer program to determine the optimal facility selection and service rate assignment. Consumers aim to maximize utility when choosing facilities, ensuring no incentive to change choices in user-equilibrium. The nonlinear constraints are linearized to efficiently solve a mixed-integer linear problem.
TRANSPORTATION SCIENCE
(2022)
Article
Engineering, Civil
Thien Huy Truong Nguyen, Bree Bennett, Michael Leonard
Summary: Stochastic rainfall models are important for evaluating hydrological risks, but there are discrepancies between rainfall metrics and flow metrics. The performance of different models varies depending on the strictness of the flow-based comparison and the region analyzed.
JOURNAL OF HYDROLOGY
(2023)
Article
Engineering, Electrical & Electronic
Kedir Mamo Besher, Sara Beitelspacher, Juan Ivan Nieto-Hipolito, Mohammed Zamshed Ali
Summary: This paper studied the current healthcare packet routing process in IoT and proposed a sensor driven solution to prioritize healthcare data routing in congested IoT networks. By adding a healthcare data identifier in IP packet header at the sensor level and modifying QoS software at the network router level, the proposed system successfully provides the highest priority to healthcare data packet routing in congested IoT networks.
IEEE SENSORS JOURNAL
(2021)
Article
Transportation
Sijia Hao, Rui Song, Shiwei He
Summary: This paper focuses on the timetabling problem for a congested urban rail transit network, proposing an optimization model that considers dwell time as a decision variable to control the number of boarding passengers. The study successfully addresses the previously unstudied issue of calculating the number of time-varying transfer passengers.
TRANSPORTMETRICA B-TRANSPORT DYNAMICS
(2022)
Article
Management
Juan P. Cavada, Cristian E. Cortes, Marcel Goic, Andres Weintraub, Juan Zambrano
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2020)
Article
Computer Science, Information Systems
Juan Pablo Cavada, Cristian E. Cortes, Pablo A. Rey
Article
Operations Research & Management Science
Javiera Barrera, Rodrigo A. Carrasco, Eduardo Moreno
Article
Engineering, Multidisciplinary
Gianpiero Canessa, Eduardo Moreno, Bernardo K. Pagnoncelli
Summary: This work explores a risk-averse ultimate pit problem with uncertain mineral grade, deriving conditions for generating nested pits by varying risk levels. It introduces two desirable properties and shows that only an entropic risk measure satisfies them. A two-stage stochastic programming formulation is proposed, along with an efficient approximation scheme for solving it, demonstrated in both a constructed example and a real-world mine in Chile.
OPTIMIZATION AND ENGINEERING
(2021)
Review
Geosciences, Multidisciplinary
Luis Yanez-Sandivari, Cristian E. Cortes, Pablo A. Rey
Summary: The article presents a comprehensive review of recent literature on humanitarian logistics and disaster response operations, focusing on optimization models, data availability, the dynamic nature of disasters, and multiple objectives. It identifies theories, relevant research methods, and topics for future research, resulting in a multidimensional framework for optimizing humanitarian logistics decisions.
INTERNATIONAL JOURNAL OF DISASTER RISK REDUCTION
(2021)
Article
Computer Science, Software Engineering
Cristian Ramirez-Pico, Eduardo Moreno
Summary: The method presented deals with solving two-stage stochastic linear programming problems by partitioning the uncertainty space and addressing discrete problems for each subregion. By formulating second-stage subproblems and utilizing dual information, conditions for the partition to obtain an optimal solution are provided. Computational experiments demonstrate how the method automatically adjusts the partition of the uncertainty space in regions of interest.
MATHEMATICAL PROGRAMMING
(2022)
Article
Transportation
Hector Lopez-Ospina, Cristian E. Cortes, Juan Perez, Romario Pena, Juan Carlos Figueroa-Garcia, Jorge Urrutia-Mosquera
Summary: This paper introduces a bi-objective distribution model for urban trips constrained by origins and destinations, with a focus on maximizing entropy. It employs a fuzzy-entropy approach to estimate parameters and measures the uncertainty associated with fuzzy variables. By utilizing compromise programming with weighted sum objectives, the problem is solved uniquely in one step, demonstrating improved predictive capabilities compared to traditional fuzzy models.
TRANSPORTMETRICA A-TRANSPORT SCIENCE
(2022)
Article
Engineering, Electrical & Electronic
Javiera Barrera, Pauline Beaupuits, Eduardo Moreno, Rodrigo Moreno, Francisco D. Munoz
Summary: This study investigates the impact of ignoring correlations between component failures on optimal network design in power systems exposed to natural hazards. The results show that considering correlations is crucial, as it can significantly alter the optimal design and increase expected levels of curtailed demand. Additionally, investing in HVDC transmission lines may be more optimal than AC lines in disaster-prone areas, due to the flexibility they offer in controlling power flows.
ELECTRIC POWER SYSTEMS RESEARCH
(2021)
Article
Computer Science, Hardware & Architecture
Javiera Barrera, Eduardo Moreno, Gonzalo Munoz, Pablo Romero
Summary: This study proposes a novel reliability optimization framework for network design, which can efficiently obtain optimal solutions in cases where failure probabilities are independent but not necessarily identical.
Article
Operations Research & Management Science
Javiera Barrera, Eduardo Moreno, Gonzalo Munoz
Summary: This paper discusses the widespread application of convexification based on convex envelopes in nonlinear optimization, and introduces a new family of functions called ray-concave functions. The authors provide sufficient conditions for computing the convex envelopes of ray-concave functions over arbitrary polytopes. This research offers new insights into previously known convex envelopes and derives a previously unknown convex envelope for a function in probability contexts.
OPTIMIZATION LETTERS
(2022)
Article
Computer Science, Information Systems
Luis Yanez Sandivari, Cristian E. Cortes, Pablo A. A. Rey
Summary: This paper proposes a stepwise development process for constructing a comprehensive model to solve disaster planning and response problems. The suggested approach incorporates factors such as response time sensitivity, social costs, material convergence, and uncertainty. The model is applied to real case study data and demonstrates a progressive decrease in costs as well as the social cost component. It allows decision-makers to test the sensitivity of results and incorporate multiple objectives accordingly.
Article
Engineering, Civil
Cristian E. Cortes, Bruno Stefoni
Summary: Emergency services are crucial in cities and are always under public scrutiny. To dispatch emergency vehicles efficiently, realistic shortest-path algorithms involving the movement of emergency vehicles within an urban network are needed. By studying emergency vehicle trajectories at a microscopic level, the impact of emergency vehicle travel shared with other vehicles can be accurately modeled.
JOURNAL OF ADVANCED TRANSPORTATION
(2023)
Article
Operations Research & Management Science
Cristian Ramirez-Pico, Ivana Ljubic, Eduardo Moreno
Summary: This paper presents a novel Benders adaptive-cuts method for solving two-stage stochastic problems. The method aggregates Benders cuts based on a partition of the scenarios, which is dynamically refined using linear program-dual information. Computational experiments validate the superiority of the new method over other Benders methods and standard methods for solving large-scale stochastic problems.
TRANSPORTATION SCIENCE
(2023)
Article
Operations Research & Management Science
Juan P. Cavada, Cristian E. Cortes, Gustavo Henriquez, Pablo A. Rey
Summary: A mixed integer linear programming model is proposed for personnel planning at Santiago International Airport. The model generates shift rosters for a month, considering heterogeneous workers and various constraints. Solutions are generated using a commercial solver, improving both personnel availability and worker welfare compared to previous manual methods.
OPERATIONAL RESEARCH
(2023)
Article
Economics
Rodrigo Harrison, Pedro Jara-Moroni
Summary: In the study of global games with strategic substitutes, a unique equilibrium is selected as incomplete information vanishes under payoff asymmetry. The equilibrium profile is characterized by players employing switching strategies at different cutoff signals, determined by payoff asymmetry. This research extends the global game literature to new applications in industrial organization, collective action problems, finance, and other fields.
INTERNATIONAL ECONOMIC REVIEW
(2021)
Article
Economics
Songyot Kitthamkesorn, Anthony Chen, Seungkyu Ryu, Sathaporn Opasanon
Summary: The study introduces a new mathematical model to determine the optimal location of park-and-ride facilities, addressing the limitations of traditional models and considering factors such as route similarity and user heterogeneity.
TRANSPORTATION RESEARCH PART B-METHODOLOGICAL
(2024)