Article
Management
Qihao Liu, Xinyu Li, Liang Gao, Jiaxin Fan
Summary: Process planning and shop scheduling are two independent subsystems in traditional flexible manufacturing systems. Integrated process planning and scheduling (IPPS) is the main focus of production research. This study proposes two MILP models to solve IPPS problems, with full-flexibility and semi-flexibility for small-scale and larger-scale problems respectively. Experimental results demonstrate the superiority of the two models in solving IPPS problems.
JOURNAL OF THE OPERATIONAL RESEARCH SOCIETY
(2023)
Article
Thermodynamics
Verena Halmschlager, Rene Hofmann
Summary: Holistic energy efficiency solutions are crucial for minimizing energy consumption in today's industry, while incorporating production scheduling into energy optimization can significantly enhance energy efficiency.
Article
Mathematics
Tzu-Chin Lin, Bertrand M. T. Lin
Summary: Taichung is the hub of the precision optical industry in Taiwan, with modernized and automated optics companies running 24-hour production lines. However, the current manual shift scheduling system for engineers is time-consuming and often leads to workload imbalances. This study aims to provide a solution for Glorytek to increase efficiency and optimize engineering staff allocation. The results show that an automated system significantly improves shift scheduling efficiency.
Article
Management
Cinna Seifi, Marco Schulze, Juergen Zimmermann
Summary: This paper introduces a mixed-integer linear program for a shift scheduling problem in a German potash mine, which outperforms existing solution procedures by considering production scheduling with sequence-dependent setup, changeover, and removal times, and meeting mining-specific requirements for practical implementation. Computational experiments on realistic problem instances derived from real-world data show the effectiveness of the new formulation.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2021)
Article
Management
Maarten Otten, Sander Dijkstra, Greanne Leeftink, Bas Kamphorst, Angelique Olde Meierink, Anouk Heinen, Rhode Bijlsma, Richard J. Boucherie
Summary: This paper proposes an iterative simulation optimisation approach to maximise the number of in-person consultations in the blueprint schedule of a clinic facing same-day multi-appointment patient trajectories and restrictions. The study takes into account the combined effects of early arrival times, bridging times, and waiting times, and combines an Integer Linear Program with a Monte Carlo simulation model.
JOURNAL OF THE OPERATIONAL RESEARCH SOCIETY
(2023)
Article
Economics
Ana Raquel Pena de Aguiar, Tania Rodrigues Pereira Ramos, Maria Isabel Gomes
Summary: The demand for home care services is growing steadily, especially in healthcare and social care. This study focuses on the synchronization of caregivers in social care services to improve human resources management. It introduces decision support tools to assist managers in designing operational plans and efficiently assigning caregivers to tasks. By considering teams of one caregiver that can synchronize to perform tasks requiring two caregivers, daily continuity of care and teams' synchronization can be effectively modeled.
SOCIO-ECONOMIC PLANNING SCIENCES
(2023)
Article
Computer Science, Information Systems
I Fikry, Amr Eltawil, Mohamed Gheith
Summary: This study considers the crop rotation problem while incorporating uncertainties related to water supply/demand and net return, using robust optimization for numerical tractability. The main objectives include optimal cropping plans, reasonable income for farmers, and tactical consideration of water uncertainties. The robustness level adjustment in robust optimization provides insights for tradeoff decisions in the face of uncertainty sets.
Article
Management
M. A. Forbes, M. G. Harris, H. M. Jansen, F. A. van der Schoot, T. Taimre
Summary: This article proposes a new approach to integrating simulation into the optimization model, which solves stochastic resource allocation problems and derives strong Benders cuts. The approach is tested on nursing home shift scheduling and airport check-in counter allocation problems, achieving exact solutions within a reasonable amount of time.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2024)
Article
Economics
Fotios A. Katsigiannis, Konstantinos G. Zografos
Summary: This paper addresses the lack of consideration for airlines' flight scheduling flexibility preferences in existing Airport Slot Allocation (ASA) literature by proposing a novel framework that integrates these preferences with dynamic allocation of airport resources. By introducing the Timing Flexibility Indicator (TFI) and considering constraints from IATA WSG, the proposed framework improves airport capacity utilization and slot schedules, leading to reduced total and maximum displacement and significant improvements in displaced slot requests and passenger satisfaction.
TRANSPORTATION RESEARCH PART B-METHODOLOGICAL
(2021)
Article
Management
Osman T. Aydas, Anthony D. Ross, Matthew C. Scanlon, Buket Aydas
Summary: This study examines medium-term integrated nurse staffing policy options for hospital intensive care units, aiming to reduce nurse staffing costs while balancing the risks of under/over-staffing. Dynamic nurse staffing using historical patient data resulted in over 3% higher cost savings compared to fixed staffing policies.
JOURNAL OF THE OPERATIONAL RESEARCH SOCIETY
(2021)
Article
Computer Science, Artificial Intelligence
Mojahid Saeed Osman
Summary: This paper introduces an algorithmic method that hybridizes solution procedures with an optimization model to solve the problem of scheduling and allocating changeover tasks. Three priority rules are identified and investigated as objective functions to minimize total changeover time and maximize worker utilization, while satisfying task-sequence-dependency and worker-limit constraints. The proposed hybrid approach provides effective changeover time and worker utilization.
EXPERT SYSTEMS WITH APPLICATIONS
(2021)
Article
Mathematics
Fabian Riquelme, Elizabeth Montero, Leslie Perez-Caceres, Nicolas Rojas-Morales
Summary: This work focuses on generating conference programs that organize talks into different tracks, with main contributions in literature review, problem formulation and benchmarking, and heuristic approach. A new track-based conference scheduling problem formulation is introduced, with a proposed heuristic method for solving it efficiently.
Article
Computer Science, Information Systems
Yarong Chen, Ya-Chih Tsai, Fuh-Der Chou
Summary: This paper focuses on the hybrid flow shop scheduling problem and proposes a new mixed integer programming model and two new lower bounds based on the bin-packing concept. The proposed model is compared with existing models using two sets of small and small-to-medium problems, and the effectiveness of the proposed lower bound is also demonstrated.
Article
Management
Teobaldo Bulhoes, Rubens Correia, Anand Subramanian
Summary: Scheduling technical sessions for scientific events is a challenging task, with different conferences having unique characteristics requiring individual approaches. Maximizing clustering of papers with common topics in the same session is a beneficial strategy. Mathematical formulations prove NP-hard, with different model variations providing solutions for instances of varying sizes.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2022)
Article
Mathematics
Rafael L. Patrao, Reinaldo C. Garcia, Joao M. da Silva
Summary: The increasing urban population worldwide puts pressure on public services, especially healthcare. This study proposes an integer linear programming model to improve the efficiency of surgical centers and reduce the waiting time for surgeries. The model considers case-mix planning and master surgical scheduling problems. Promising results were obtained using data from a hospital in Turin, Italy, showing a significant reduction in the surgical waiting list.
Article
Engineering, Multidisciplinary
Ebru Yilmaz, Rizvan Erol
ENGINEERING OPTIMIZATION
(2015)
Article
Energy & Fuels
Onur Derse, Elifcan Gocmen, Ebru Yilmaz, Rizvan Erol
Summary: This article presents a mathematical programming model that aims to minimize the costs associated with the production, storage, transportation, safety, location, and staff assignment decisions of hydrogen energy. Unlike other studies, this article also includes considerations for production, safety, and staff assignment, making the model more practical and comprehensive. Computational results demonstrate that the proposed model effectively addresses the coverage needs of all regions and minimizes total costs in real-world scenarios.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2022)
Article
Energy & Fuels
Onur Derse, Ebru Yilmaz
Summary: Renewable energy sources (RES) have gained attraction in recent years. This study evaluates 81 provinces in Turkey using Pareto diagram and estimates long-term electricity consumption for 13 provinces using ARIMA and Time Series Analysis methods. Modeling an integrated optimum site selection problem in GAMS 23.5 software based on predicted future energy demand, the study makes 41 installation decisions for strategic optimal site selection between 2021 and 2025, with a focus on minimizing total cost. The computational results show effective solutions and cost reduction by increasing wind energy use up to 4-5% to reduce total cost by approximately 3.62% from the current 3.5% usage.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2022)
Article
Chemistry, Multidisciplinary
Emine Bozoklar, Ebru Yilmaz
Summary: This study aims to design flexible manufacturing cells with routing flexibility. It develops a weighted mixed-integer linear mathematical programming model to find optimal part routing in flexible manufacturing cells while considering various constraints and objectives. The model simultaneously minimizes the weighted sum of five objective functions, including intracellular and intercellular movements, workload and labor-system unbalance. The study integrates these factors to provide a comprehensive approach for optimizing the design of flexible manufacturing cells, with the potential to enhance system performance.
APPLIED SCIENCES-BASEL
(2023)
