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We consider a manufacturer and an e-platform where the manufacturer sells products through offline and e-platform channels under the cap-and-trade scheme. The interaction between the two channels produces the cross-channel effect (CCE). This manufacturer cooperates with the e-platform in the agency or reseller mode. In addition, the platform shares its observed data with the manufacturer and the blockchain can achieve traceability and high transparency of these data. We formulate a Stackelberg game to derive the following results: In the agency mode, the optimal service level is independent of (decreases with) CCE without (with) blockchain. CCE positively affects the optimal service level in the reseller mode and the optimal service level has no impact on (increases with) the cap in the agency (reseller) mode. Second, when the platform-enabled power is high (low), the platform is (not) willing to adopt blockchain. Third, coordination of the manufacturer and platform only can be achieved in the agency mode when CCE is low with blockchain. The reseller mode can (cannot) achieve coordination of the two firms with (without) blockchain. We also consider the cases where the manufacturer serves as the leader and the omni-channel strategy is adopted to check the robustness of the coordination results. [ABSTRACT FROM AUTHOR]

This paper considers a supply chain consisting of a manufacturer and a retailer. The manufacturer sells its products through the retailer and an online platform and adopts green technology in the blockchain era. The platform can operate with marketplace mode or reselling mode. The network effect is considered to reflect the power of the platform to enlarge the potential market size. In the decentralised supply chain, the online platform encroaches the offline demand despite the same retail price. The increase of the network coefficient improves the abatement level, and benefits the manufacturer and the platform but damages the retailer's profit. For the supply chain coordination, the abatement level with reselling mode in the centralised supply chain is less than that in the decentralised supply chain if the network coefficient is high. Both marketplace mode and reselling mode can coordinate the supply chain if the network coefficient is low. Blockchain technology helps the products become greener and brings more profits for the manufacturer and the platform. And it induces supply chain coordination. Based on real data of a supply chain, its profit is increased by 3% after coordination. [ABSTRACT FROM AUTHOR]

To support the 2021 Manufacturing & Service Operations Management (M&SOM) Data-Driven Research Challenge, RiRiShun Logistics (a Haier group subsidiary focusing on logistics service for home appliances) provides MSOM members with logistics operational-level data for data-driven research. This paper provides a detailed description of the data associated with over 14 million orders from 149 clients (the consigners) associated with 4.2 million end consumers (the recipients and end users of the appliances) in China, involving 18,000 stock keeping units operated at 103 warehouses. Researchers are welcomed to develop econometric models, data-driven optimization techniques, analytical models, and algorithm designs by using this data set to address questions suggested by company managers. History: This paper has been accepted as part of the 2021 M&SOM Data-Driven Research Challenge. Funding: This work was supported by the National Natural Science Foundation of China [Grants 72091215/72091210, 71871207, 71991464/71991460, and 71921001]. Supplemental Material: Data and the online appendix are is available at https://doi.org/10.1287/msom.2021.0994. [ABSTRACT FROM AUTHOR]

Autonomous vehicle storage and retrieval systems have greatly increased in popularity in the last decade. In such a system, at each tier multiple roaming vehicles transport totes between the storage locations and the lifts. However, this may lead to vehicle interference. We study in which order and by which vehicle the storage and retrieval requests should be executed to minimize the makespan, without vehicle interference. The optimal storage locations for incoming totes are also determined. A blocking mitigation protocol is proposed to address vehicle interference. We propose a two‐phase matheuristic, where in the first phase, the tier is divided into zones, with each zone assigned its own vehicle. The second phase focuses on reassigning requests between adjacent vehicles to obtain improved solutions. The models proposed in both phases are solved to optimality in polynomial time and pseudo‐polynomial time, respectively. Computational experiments show that the matheuristic produces high‐quality solutions within a few seconds, even for large‐sized instances, making it suitable for real‐time decisions. Compared to methods commonly used in practice, our matheuristic can reduce the makespan by up to 15%. Our results show that making integrated decisions that combine storage assignment and request scheduling, is more beneficial than sequential optimization in terms of throughput performance, space utilization and overall system cost. We also find that increasing the number of vehicles has a diminishing return effect on the makespan. Another finding is that the system with a large number of short storage aisles leads to higher throughput capacity than that with a small number of long storage aisles. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid perovskites have electronic and optoelectronic properties that make them appealing in many device applications.sup.1-4. Although many approaches focus on polycrystalline materials.sup.5-7, single-crystal hybrid perovskites show improved carrier transport and enhanced stability over their polycrystalline counterparts, due to their orientation-dependent transport behaviour.sup.8-10 and lower defect concentrations.sup.11,12. However, the fabrication of single-crystal hybrid perovskites, and controlling their morphology and composition, are challenging.sup.12. Here we report a solution-based lithography-assisted epitaxial-growth-and-transfer method for fabricating single-crystal hybrid perovskites on arbitrary substrates, with precise control of their thickness (from about 600 nanometres to about 100 micrometres), area (continuous thin films up to about 5.5 centimetres by 5.5 centimetres), and composition gradient in the thickness direction (for example, from methylammonium lead iodide, MAPbI.sub.3, to MAPb.sub.0.5Sn.sub.0.5I.sub.3). The transferred single-crystal hybrid perovskites are of comparable quality to those directly grown on epitaxial substrates, and are mechanically flexible depending on the thickness. Lead-tin gradient alloying allows the formation of a graded electronic bandgap, which increases the carrier mobility and impedes carrier recombination. Devices based on these single-crystal hybrid perovskites show not only high stability against various degradation factors but also good performance (for example, solar cells based on lead-tin-gradient structures with an average efficiency of 18.77 per cent). A solution-based lithography-assisted epitaxial-growth-and-transfer method is used to fabricate single-crystal hybrid perovskites on any surface, with precise control of the thickness, area and chemical composition gradient., Author(s): Yusheng Lei [sup.1] , Yimu Chen [sup.1] , Ruiqi Zhang [sup.1] , Yuheng Li [sup.1] , Qizhang Yan [sup.1] , Seunghyun Lee [sup.2] , Yugang Yu [sup.3] , Hsinhan [...]

Strain engineering is a powerful tool with which to enhance semiconductor device performance.sup.1,2. Halide perovskites have shown great promise in device applications owing to their remarkable electronic and optoelectronic properties.sup.3-5. Although applying strain to halide perovskites has been frequently attempted, including using hydrostatic pressurization.sup.6-8, electrostriction.sup.9, annealing.sup.10-12, van der Waals force.sup.13, thermal expansion mismatch.sup.14, and heat-induced substrate phase transition.sup.15, the controllable and device-compatible strain engineering of halide perovskites by chemical epitaxy remains a challenge, owing to the absence of suitable lattice-mismatched epitaxial substrates. Here we report the strained epitaxial growth of halide perovskite single-crystal thin films on lattice-mismatched halide perovskite substrates. We investigated strain engineering of [alpha]-formamidinium lead iodide ([alpha]-FAPbI.sub.3) using both experimental techniques and theoretical calculations. By tailoring the substrate composition--and therefore its lattice parameter--a compressive strain as high as 2.4 per cent is applied to the epitaxial [alpha]-FAPbI.sub.3 thin film. We demonstrate that this strain effectively changes the crystal structure, reduces the bandgap and increases the hole mobility of [alpha]-FAPbI.sub.3. Strained epitaxy is also shown to have a substantial stabilization effect on the [alpha]-FAPbI.sub.3 phase owing to the synergistic effects of epitaxial stabilization and strain neutralization. As an example, strain engineering is applied to enhance the performance of an [alpha]-FAPbI.sub.3-based photodetector. A method of deposition of mixed-cation hybrid perovskite films as lattice-mismatched substrates for an [alpha]-FAPbI.sub.3 film is described, giving strains of up to 2.4 per cent while also stabilizing the metastable [alpha]-FAPbI.sub.3 phase for several hundred days., Author(s): Yimu Chen [sup.1] , Yusheng Lei [sup.1] , Yuheng Li [sup.1] , Yugang Yu [sup.2] , Jinze Cai [sup.2] , Ming-Hui Chiu [sup.3] , Rahul Rao [sup.4] , Yue [...]