Advances, Updates, and Analytics for the Computation-Ready, Experimental Metal–Organic Framework Database: CoRE MOF 2019

Over 14 000 porous, three-dimensional metal–organic framework structures are compiled and analyzed as a part of an update to the Computation-Ready, Experimental Metal–Organic Framework Database (CoRE MOF Database). The updated database includes additional structures that were contributed by CoRE MOF users, obtained from updates of the Cambridge Structural Database and a Web of Science search, and derived through semiautomated reconstruction of disordered structures using a topology-based crystal generator. In addition, value is added to the CoRE MOF database through new analyses that can speed up future nanoporous materials discovery activities, including open metal site detection and duplicate searches. Crystal structures (only for the subset that underwent significant changes during curation), pore analytics, and physical property data are included with the publicly available CoRE MOF 2019 database

Essays on Energy Operations

The global energy landscape is going through major shifts triggered by consumer preferences, regulations, and technological development. My dissertation develops optimization models to de-rive insights into strategic decisions in energy operations management. In the first essay, I examine how blockchain-enabled peer-to-peer energy trading shifts electricity consumers’ investment in renewable energy. Using the equilibrium model, I show that electricity consumers are always better off by participating in the virtual network, with their resulting cost savings averaging 9.7%. I also prove that blockchain is able to fully coordinate heterogeneous participants in the network to minimize the total cost in the system. The second essay addresses how a Transmission System Operator (TransCo) can optimally invest in a long-distance transmission line to allow renewable energy development by a Power Generation Company (GenCo) in a geographically remote region. Using a continuous-time, infinite-horizon, Stackelberg game between TransCo and GenCo, I show that transmission and generation act as complements with regard to the value functions for both companies. I derive the value-maximizing transmission fee charged by TransCo to GenCo for each unit of energy exported via transmission lines. I characterize a Pareto-improving cost-sharing contract through which both companies can improve the value of their investment. The third essay focuses on how to better manage a decentralized supply chain of an oil-field service company. To minimize the transportation and inventory holding costs of different members in a cross-docking supply chain, I formulate multi-period, mixed-integer programming models. I use structural properties of optimal solutions to show that different collaborations in the supply chain can generate significant cost savings for individual supply chain members, whereas the quantified cost savings exhibit significant variations depending on product weight and holding cost. I also develop a Stackelberg pricing game between an independent logistics company and oil wells seeking to lower their costs by outsourcing their operations. I provide the best response of oil wells to the price of outsourcing services and the structure of the logistics provider’s optimal pricing policy

Optimal Shipping, Collaboration, and Outsourcing Decisions in a Hybrid Cross-docking Supply Chain

This repository contains code associated with our accepted paper in IISE Transactions titled "Optimal Shipping, Collaboration, and Outsourcing Decisions in a Hybrid Cross-docking Supply Chain." To briefly summarize, 1. value of collaboration.zip - includes code to evaluate the value of upstream collaboration and downstream collaboration in a hybrid cross-docking supply chain. The "upstream" folder includes code to evaluate the upstream collaboration benefits to the cross-dock in a varying number of products (q=2, 4, 6). The "downstream" folder includes code to evaluate the downstream collaboration benefits to the oil-well facilities (OWFs) in a varying number of products (q=2, 4, 6). 2. outsourcing.zip - includes code to obtain the optimal outsourcing decision for oil well facilities and pricing decisions of the logistics provider using the sample approximation method. The "best response (OWF-outsourcing-decision)" folder includes code to obtain the threshold for each individual OWF's optimal outsourcing decision, such that for any outsourcing price lower than the threshold, the OWF outsources to the logistics provider. Given the OWFs' best responses, the "outsourcing price" folder includes code to evaluate the optimal outsourcing price for the logistics provider. The code evaluates the optimal pricing strategy under a varying number of OWFs (M=1,2,3,4) in supplemental materials. To conduct the numerical experiment in the paper, the author team used the ILOG AMPL CPLEX system (ILOG AMPL CPLEX 2021) on Intel Core i7-8650 CPU with a 2.11 GHz processor and 16 GB of RAM

Data-Driven Discovery of New Zeolitic Imidazolate Frameworks

The discovery of new advanced materials is important for sustainable future. Traditionally, the materials discovery rely heavily on synthetic scientists through repeated trial-and-error experiments. Theorists commonly utilized the large-sized materials database to seek the optimal materials for desired properties. Such computational approach has been quite successful in revealing the performance limits of porous materials, but often extremely difficult to predict which materials could be synthesizable from the millions of candidates. We hypothesize that collective structural signatures, extracted from known porous solids, could be served as structural descriptors, which then could be efficient data filters for screening porous materials. In this presentation, we show not-yet-synthesized ZIF topologies, filtered and modelled from both real and hypothetical zeolite databases. To filer the entries in these databases, we have identified three structural descriptors. Together with these new candidate topologies for ZIFs, we also suggest possible synthetic strategies to realize these future ZIFs

Optimal shipping, collaboration, and outsourcing decisions in a hybrid cross-docking supply chain

Motivated by the supply chain of our oil-field service industry partner, we study shipping, collaboration, and outsourcing decisions in a decentralized, three-stage supply chain consisting of suppliers, a hybrid cross-dock facility, and oil well facilities. Unlike pure cross-docking, which transships arriving products quickly downstream, hybrid cross-docking allows for inventory to remain at the cross-dock for multiple periods. We formulate multi-period, optimization models to minimize costs of different members in a hybrid cross-docking supply chain and establish structural properties of optimal solutions. We make use of those results to identify conditions under which hybrid cross-docking is more cost efficient than pure cross-docking. Our results provide managerial insights regarding when a hybrid cross-dock should be enabled, and the value of the resulting cost savings. We also quantify the value of collaboration among different stages in the supply chain. Upstream collaboration results in 1% to 9% average cost savings for the cross-dock, while downstream collaboration generates 4% to 13% in average cost savings for oil well facilities, depending on the number of products and their holding cost. We also develop a Stackelberg pricing game between a logistics company and oil well facilities seeking to lower their costs by outsourcing their transportation and inventory operations. We identify the structure of oil well facilities’ best response to the price of outsourcing services, as well as the structure of the logistics provider’s optimal pricing policy. Our findings and models, based on current literature, provide application focused tools that allow managers to improve cross-docking operations in their supply chains, realize the benefits of collaborations, and make better outsourcing decisions

NIR-Triggered High-Efficiency Self-Healable Protective Optical Coating for Vision Systems

Recently, self-healing materials have evolved to recover specific functions such as electronic, magnetic, acoustic, structural or hierarchical, and biological properties. In particular, the development of self-healing protection coatings that can be applied to lens components in vision systems such as augmented reality glasses, actuators, and image and time-of-flight sensors has received intensive attention from the industry. In the present study, we designed polythiourethane dynamic networks containing a photothermal N-butyl-substituted diimmonium borate dye to demonstrate their potential applications in self-healing protection coatings for the optical components of vision systems. The optimized self-healing coating exhibited a high transmittance (∼95% in the visible-light region), tunable refractive index (up to 1.6), a moderate Abbe number (∼35), and high surface hardness (>200 MPa). When subjected to near-infrared (NIR) radiation (1064 nm), the surface temperature of the coating increased to 75 °C via the photothermal effect and self-healing of the scratched coatings occurred via a dynamic thiourethane exchange reaction. The coating was applied to a lens protector, and its self-healing performance was demonstrated. The light signal distorted by the scratched surface of the coating was perfectly restored after NIR-induced self-healing. The photoinduced self-healing process can also autonomously occur under sunlight with low energy consumption

NIR-Triggered High-Efficiency Self-Healable Protective Optical Coating for Vision Systems

Recently, self-healing materials have evolved to recover specific functions such as electronic, magnetic, acoustic, structural or hierarchical, and biological properties. In particular, the development of self-healing protection coatings that can be applied to lens components in vision systems such as augmented reality glasses, actuators, and image and time-of-flight sensors has received intensive attention from the industry. In the present study, we designed polythiourethane dynamic networks containing a photothermal N-butyl-substituted diimmonium borate dye to demonstrate their potential applications in self-healing protection coatings for the optical components of vision systems. The optimized self-healing coating exhibited a high transmittance (∼95% in the visible-light region), tunable refractive index (up to 1.6), a moderate Abbe number (∼35), and high surface hardness (>200 MPa). When subjected to near-infrared (NIR) radiation (1064 nm), the surface temperature of the coating increased to 75 °C via the photothermal effect and self-healing of the scratched coatings occurred via a dynamic thiourethane exchange reaction. The coating was applied to a lens protector, and its self-healing performance was demonstrated. The light signal distorted by the scratched surface of the coating was perfectly restored after NIR-induced self-healing. The photoinduced self-healing process can also autonomously occur under sunlight with low energy consumption