Article
Computer Science, Interdisciplinary Applications
Frank Piedra-Jimenez, Natalia G. Tassin, Juan M. Novas, Maria Analia Rodriguez
Summary: This study proposes a mathematical framework based on Generalized Disjunctive Programming for addressing the Forest Biorefinery Supply Chain (FBSC) design problem. The approach simultaneously solves the dynamic capacity allocation and facilities' co-location issues, promoting circularity of the network through flexible processing recipes and utilization of multiple biomass residues.
COMPUTERS & CHEMICAL ENGINEERING
(2022)
Article
Engineering, Industrial
Shengnan Zhao, Ying Meng, Lijie Su, Jiyin Liu, Lixin Tang
Summary: This paper addresses a new optimal plate design problem in steel production, considering slab selection. It formulates the problem as a mixed integer nonlinear programming model with generalized disjunctive programming constraints. A logic-based outer approximation algorithm is proposed to solve the problem. Numerical results demonstrate the effectiveness and computational efficiency of the proposed algorithm.
INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
(2023)
Article
Computer Science, Interdisciplinary Applications
Bruno Theozzo, Moises Teles dos Santos
Summary: This study proposes an optimization framework for biorefineries design that considers the complex dynamics of forest systems, aiming to improve efficiency. The model, formulated as a MILP for maximizing the operational Net Present Value, integrates decision layers including biomass supply, conversion processes, storage, and markets. A case-study on lignin extraction in eucalyptus Kraft Pulp mills in Brazil demonstrates the importance of factors such as land availability, forest productivity, and interest rates in facility location and sizing.
COMPUTERS & CHEMICAL ENGINEERING
(2021)
Article
Computer Science, Interdisciplinary Applications
Qi Chen, Yunshan Liu, Grant Seastream, John D. Siirola, Ignacio E. Grossmann
Summary: Pyosyn is an open-source framework for systematic superstructure-based process synthesis, with a new representation, superstructure generation approaches, modeling, and solution strategies. The framework introduces a new representation called Pyosyn Graph (PSG) consisting of units, ports, and streams, with support for nested units and new single-choice units. Superstructure generation strategies are based on both library-assisted and direct-hierarchical means-ends analysis, including generalized port annotations for compatibility conditions between connected unit ports.
COMPUTERS & CHEMICAL ENGINEERING
(2021)
Article
Engineering, Chemical
Xiang Zhang, Teng Zhou, Ka Ming Ng
Summary: The design of cosmetics requires meeting multiple functional and hard-to-quantify sensorial product attributes, which can be achieved by a large number of cosmetic ingredients. To expedite cosmetic formulation, an optimization-based approach utilizing a hierarchy of models in an iterative manner is presented. This approach improves efficiency and finds better solutions for creating high-quality cosmetic products.
Article
Chemistry, Multidisciplinary
Mohammadamin Zarei, Ali Cherif, Ha-Jun Yoon, J. Jay Liu, Chul-Jin Lee
Summary: Due to the scarcity of fossil fuels and environmental concerns, renewable energy sources have gained attention. In this study, multi-objective function optimization was used to design a sustainable biofuel supply chain based on greenhouse gas emissions and cost. The results show that the sustainable solution has a cost of $6.63 per gallon of gasoline-equivalent and emits 674.83 grams of CO2-equivalents per gallon of gasoline-equivalent.
Article
Computer Science, Software Engineering
Tamas Kis, Marko Horvath
Summary: This paper reconsiders a technique for constructing strong MIP formulations for disjunctive constraints, based on the Cayley Embedding of the union of polytopes. The paper provides a full characterization of the facets of the formulated union, along with applications in various fields and a new formulation for piecewise linear functions on grid triangulations. The applications demonstrate the richness of disjunctive constraints for which the method can be applied.
MATHEMATICAL PROGRAMMING
(2022)
Article
Green & Sustainable Science & Technology
Luca Moretti, Mario Milani, Giovanni Gustavo Lozza, Giampaolo Manzolini
Summary: The optimal design of a biomass supply chain is a complex problem that needs to consider multiple interrelated factors. The study uses Mixed Integer Linear Programming to economically optimize the design and management strategy of the Advanced Biofuel Supply Chains, highlighting the advantages of a multi-feedstock approach.
Article
Engineering, Multidisciplinary
Nathan Stewart, Bryan Arguello, Matthew Hoffman, Bethany Nicholson, Richard Garrett
Summary: Optimal mitigation planning for highly disruptive contingencies in a transmission-level power system requires considering dynamic power system constraints. This research introduces a novel formulation that allows for the analysis of the interdependencies between mitigation planning, preventive control, and emergency control. Demonstrations on a test system show the effectiveness of using these three strategies together in maintaining robust power system operation.
OPTIMIZATION AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Qi Chen, Emma S. Johnson, David E. Bernal, Romeo Valentin, Sunjeev Kale, Johnny Bates, John D. Siirola, Ignacio E. Grossmann
Summary: This article introduces three core principles for engineering-oriented integrated modeling and optimization tool sets, and explains how Pyomo.GDP for Generalized Disjunctive Programming (GDP) advances this vision. By implementing a new logical expression system and two logic-based global optimization solvers on Pyomo.GDP, it improves the handling of logical constraints in nonlinear network design problems. The flexible array of solution paths available to GDP models and the new library of GDP models demonstrate the value of multiple solution approaches.
OPTIMIZATION AND ENGINEERING
(2022)
Article
Energy & Fuels
Dongho Han, Jay H. Lee
Summary: Microgrid (MG) is designed to accommodate distributed renewable energy sources and manage electricity generation using dispatch and storage systems to meet local demand. Multi-microgrid (MMG) systems can alleviate demand-supply mismatch issues through energy trading between individual MGs, but their design and operation become more complex. A two-stage stochastic decision-making approach is proposed in this study to design and operate an MMG while considering both capital and operating costs for electric cable installations. Stochastic models are developed using real weather data to describe the uncertain nature of energy production through renewable sources, and decisions are made in the first stage regarding the installation of electric cables between individual MGs to achieve the best tradeoff.
Article
Agricultural Engineering
J. C. Lopez-Linares, J. M. Romero-Garcia, I. Romero, E. Ruiz, E. Castro
Summary: This work investigated three process configurations for the biorefinery of olive oil mill leaves (OL), which include natural antioxidants, lignin, and bioethanol. Configuration 1 achieved the simplest process but had poor biomass fractionation. Configuration 2 included ethanol extraction to enhance the recovery of natural antioxidants. Configuration 3 achieved better fractionation and the highest bioethanol production with a yield of 71% of the theoretical yield. It also generated a liquid stream with higher lignin content, facilitating the obtainment of high purity lignin.
INDUSTRIAL CROPS AND PRODUCTS
(2023)
Article
Economics
Qiaolin Hu, Weihua Gu, Shuaian Wang
Summary: This paper investigates the optimal container subsidies for shippers to promote intermodal shipping involving waterways in a regional transportation network. A case study suggests that an optimally designed subsidy scheme can increase the intermodal split of container transport by 16%.
TRANSPORTATION RESEARCH PART E-LOGISTICS AND TRANSPORTATION REVIEW
(2022)
Article
Environmental Studies
Nelson Morales, Diego Mancilla, Roberto Miranda, Javier Vallejos
Summary: This study proposes an improved method for designing a sublevel stoping mine, which determines the optimal layout of stopes through enumeration and optimization models. The method ensures the profitability and geotechnical stability of the generated stopes, and organizes them into drifts and levels for a more operational layout. The method is suitable for algorithmic and theoretical contributions, and has been tested on different block models, showing both feasibility and efficiency of the resulting optimal layouts. Sensibility analyses demonstrate the robustness of the optimal solutions to variations in economic values and geometric locations of the stopes.
Article
Green & Sustainable Science & Technology
Nicolas M. Clauser, Fernando E. Felissia, Maria C. Area, Maria E. Vallejos
Summary: Sustainable biomass valorization and development of conversion processes can bring multiple benefits to society. Industrial biorefinery schemes require technical and economic assessments, while also focusing on process design and optimization for efficiency and profitability.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Engineering, Chemical
Ahmad Al-Douri, Abdulrahman S. Alsuhaibani, Margaux Moore, Rasmus B. Nielsen, Amro A. El-Baz, Mahmoud M. El-Halwagi
Summary: The paper discusses the substantial increases in shale gas production due to advances in hydraulic fracturing, with a key opportunity being the use of liquified natural gas (LNG) as a shipping fuel for sustainable development. Research shows that incorporating renewable energy in LNG production can further reduce emissions compared to conventional fuels.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Tania Itzel Serrano-Arevalo, Luis Fernando Lira-Barragan, Mahmoud M. El-Halwagi, Jose Maria Ponce-Ortega
Summary: This paper presents a mathematical programming approach for managing wastewater in shale gas production. The approach considers the variability of wastewater characteristics and seasonal variabilities in freshwater availability, aiming to achieve economic and environmental objectives through stream segregation and water reuse.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Green & Sustainable Science & Technology
Fahad M. Al-Fadhli, Nawaf Alhajeri, Hisham Ettouney, Debalina Sengupta, Mark Holtzapple, Mahmoud M. El-Halwagi
Summary: This paper investigates the goals of sustainable water and energy production and proposes a novel systems-integration approach. Using the case study of the Kuwait water-energy nexus, it explores optimized design and operational strategies to meet economic and environmental objectives.
CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY
(2022)
Article
Geochemistry & Geophysics
Tim Jesper Suhrhoff, Joerg Rickli, Marcus Christl, Elena G. Vologina, Viet Pham, Moustafa Belhadj, Eugene V. Sklyarov, Catherine Jeandel, Derek Vance
Summary: This study provides a detailed analysis of weathering fluxes at Lake Baikal and evaluates the potential of lake records for understanding denudation and weathering processes. The results show that the denudation rates at Lake Baikal are significantly lower than the global average, while the chemical weathering rates are comparable to global values. The variation in denudation rates between the north and south of the catchment may be attributed to the stabilizing effect of permafrost soils. The study also reveals significant differences in trace element concentrations between the lake and inflowing rivers, suggesting the role of pH-induced changes and the formation of authigenic Fe-Mn (oxyhydr)oxide phases in trace element removal. The isotopic composition of strontium is uniform within the lake, indicating rapid mixing, while neodymium and beryllium show isotopic variability between the basins.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Engineering, Chemical
Juan Jose Olivarez-Areyan, Sandra Cecilia Cerda-Flores, Fabricio Napoles-Rivera, Mahmoud M. El-Halwagi
Summary: This work presents an optimization model for macroscopic water networks, considering wastewater treatment, rainwater harvesting, allocation, and recycle/reuse. The systematic optimization approach provides rigorous trade-offs and synergistic opportunities for the design and operation of the macroscopic water system while considering multiple intertwined objectives.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Computer Science, Interdisciplinary Applications
N. J. Chrisandina, S. Vedant, E. Iakovou, E. N. Pistikopoulos, M. M. El-Halwagi
Summary: This article discusses the challenges faced by energy supply chain resilience and the necessity of adopting a multi-scale approach. The authors propose a framework for energy supply chain resilience and list four scales of operation.
COMPUTERS & CHEMICAL ENGINEERING
(2022)
Article
Immunology
Selin Somersan-Karakaya, Eleftherios Mylonakis, Vidya P. Menon, Jason C. Wells, Shazia Ali, Sumathi Sivapalasingam, Yiping Sun, Rafia Bhore, Jingning Mei, Jutta Miller, Lisa Cupelli, Eduardo Forleo-Neto, Andrea T. Hooper, Jennifer D. Hamilton, Cynthia Pan, Viet Pham, Yuming Zhao, Romana Hosain, Adnan Mahmood, John D. Davis, Kenneth C. Turner, Yunji Kim, Amanda Cook, Bari Kowal, Yuhwen Soo, A. Thomas DiCioccio, Gregory P. Geba, Neil Stahl, Leah Lipsich, Ned Braunstein, Gary A. Herman, George D. Yancopoulos, David M. Weinreich
Summary: In hospitalized COVID-19 patients on low-flow or no supplemental oxygen, casirivimab and imdevimab reduce viral load and likely improve clinical outcomes, with the greatest benefit observed in seronegative patients.
JOURNAL OF INFECTIOUS DISEASES
(2022)
Review
Engineering, Chemical
Cesar Ramirez-Marquez, Musaed M. Al-Thubaiti, Mariano Martin, Mahmoud M. El-Halwagi, Jose Maria Ponce-Ortega
Summary: Nowadays, industrial processes need to meet market demands and be sustainable. Process intensification (PI) offers opportunities to enhance process performance and achieve sustainability objectives. PI can be achieved through reducing resource consumption, increasing efficiency, downsizing equipment, improving throughput, and reducing environmental emissions. This perspective article discusses the background, challenges, and opportunities of PI in order to identify options for enhanced sustainability. It also explores emerging tools that can help intensify conventional processes and improve sustainable performance.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Moises Ferreyra-Quiroz, Luis Fernando Lira-Barragan, Mahmoud M. El-Halwagi, Jose Maria Ponce-Ortega
Summary: This paper proposes a mathematical programming formulation to optimize the configuration of water and CO2 in shale gas hydraulic fracturing operations. The aim is to minimize the total annual cost while considering water availability and CO2 generation. The results show that increasing the percentage of CO2 in the fracturing fluid can reduce freshwater requirements but increases the overall cost, and the availability of freshwater has an impact on the optimization.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Engineering, Chemical
Francisco Javier Lopez-Flores, Luis Fernando Lira-Barragan, Eusiel Rubio-Castro, Mahmoud M. El-Halwagi, Jose Maria Ponce-Ortega
Summary: In this study, deep learning models based on a multilayer perceptron are developed to forecast 12 month cumulative produced shale gas and 90 day produced flowback water using data from the Eagle Ford Formation. These models provide important references for decision-makers in drilling new wells. Input variables such as latitude, longitude, true vertical depth, lateral longitude, total proppant, and total fracture water are used. The trained models are then evaluated in the Burgos Basin to analyze energy benefits, freshwater consumption, and flowback water produced through well drilling in Mexico. The results show that the multilayer perceptron models perform well with high coefficient of determination and low mean absolute error values for the validation set.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Francisco Javier Lopez-Flores, Luis Fernando Lira-Barragan, Eusiel Rubio-Castro, Mahmoud M. El-Halwagi, Jose Maria Ponce-Ortega
Summary: This paper proposes a novel mathematical programming approach that combines mixed-integer nonlinear programming with machine learning models for determining operating conditions, gas production, and optimal water management in shale gas fields during the completion phase. The dataset used for developing the artificial neural network model is collected from the Eagle Ford Texas formation, selecting total cumulative gas production and flowback water as output variables. The mathematical optimization model considers machine learning models, mass balances, treatment, storage, reuse, and disposal options, as well as well location selection and economic indicators from shale gas sales. A case study demonstrates the benefits of the proposed approach, which achieves a water consumption of 6.71 L/GJ and allows for 27% of the required fracture water to be obtained through flowback water reuse, with attractive economic indicators.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Engineering, Chemical
Saul Herrera-Ovando, Arturo Jimenez-Gutierrez, Nikolaos K. Kazantzis, Mahmoud M. El-Halwagi
Summary: This study presents a probabilistic approach for inherent process safety assessment, which takes into account uncertainties and provides a more accurate evaluation and characterization of inherent process safety during the design stage of chemical processes.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Engineering, Chemical
Eman Aldamigh, Sarbajit Banerjee, Mahmoud M. El-Halwagi
Summary: Municipal solid waste (MSW) is an important resource for biomass-based monetization and decarbonization. This study combines MSW utilization with solar-assisted electrolysis to generate green hydrogen and oxygen. The results show the tradeoffs of various design and operating strategies in terms of profitability and environmental impact.
Article
Business
Jie Hao, Viet Pham, Meng Guo
Summary: This research explores whether there are differences in the impact of PCAOB Rule 3211 on audit quality and cost between female and male audit partners. The study finds that the improvement in audit quality is more pronounced for female partners after the adoption of Rule 3211, along with higher fee increases and report lag. Additionally, the presence of female CFOs or audit committee members can mitigate the effects of increased audit fees and report lag post-adoption.
JOURNAL OF BUSINESS ETHICS
(2022)
Article
Green & Sustainable Science & Technology
Marc Panu, Chi Zhang, Mahmoud M. El-Halwagi, Mike Davies, Margaux Moore
Summary: The Power to Gas (PtG) project utilizes free or low-cost electricity during mismatches between power demand and supply to convert water into hydrogen and oxygen via electrolysis, adding significant value by co-utilizing oxygen and utilizing the natural gas infrastructure for hydrogen production and chemical manufacturing.
PROCESS INTEGRATION AND OPTIMIZATION FOR SUSTAINABILITY
(2021)
