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Despite advanced supply chain planning and execution systems, manufacturers and distributors tend to observe service levels below their targets, owing to different sources of uncertainty and risks. These risks, such as drastic changes in demand, machine failures, or systems not properly configured, can lead to planning or execution issues in the supply chain. It is too expensive to have planners continually track all situations at a granular level to ensure that no deviations or configuration problems occur. We present a machine learning system that predicts service-level failures a few weeks in advance and alerts the planners. The system includes a user interface that explains the alerts and helps to identify failure fixes. We conducted this research in cooperation with Michelin. Through experiments carried out over the course of four phases, we confirmed that machine learning can help predict service-level failures. In our last experiment, planners were able to use these predictions to make adjustments on tires for which failures were predicted, resulting in an improvement in the service level of 10 percentage points. Additionally, the system enabled planners to identify recurrent issues in their supply chain, such as safety-stock computation problems, impacting the overall supply chain efficiency. The proposed system showcases the importance of reducing the silos in supply chain management.

Vast quantities of the natural terpene (R)‐limonene can be collected from food waste. Epoxidation of its two double bonds provides limonene dioxide (LDO), a difunctional epoxy monomer. However, LDO is a mixture of four isomers, two of which (trans‐LDO) are actually difunctional while the others (cis‐LDO) have one epoxide group which is significantly less reactive, as revealed by Fourier transformed infrared spectroscopic analysis of formulations cross‐linked with polyethylene imine. These results are also confirmed when preparing epoxy formulations using respectively cisor transisomers. From DFT calculations, the reactivity of each epoxide group of LDO has been assessed in model reactions with primary and secondary amines, in the presence of amine or alcohol hydrogen‐bond donors. The kinetics of cross‐linking has also been probed by differential scanning calorimetry. As measured by dynamic mechanical analysis, the resulting epoxy resins based on transisomers have a storage modulus of ca1GPa at room temperature and a glass transition temperature (Tg) of 70°C. These results demonstrate that transLDO is a promising bio‐based epoxy monomer, which could be used as an alternative to petroleum‐based epoxy monomers. Trans‐Limonene dioxide (LDO), an epoxy monomer that can be obtained from food waste, is a promising monomer for the preparation of epoxy resins. The mechanistic reasons explaining the higher reactivity of trans‐LDO relative to cis‐LDO is unraveled. Highly‐cross‐linked epoxy polymers are prepared with trans‐LDO.

Conjugated polymers with alternating electron-withdrawing and electron-donating groups along their backbone (donor–acceptor copolymers) have recently attracted attention due to high power conversion efficiency in bulk heterojunction solar cells. In an effort to understand how the bandgap in a typical donor–acceptor copolymer is reduced by internal charge transfer character and what the implications of this charge transfer are, we have synthesized the isolated repeat unit (CDTBT) of the photovoltaically highly successful PCDTBT polymer. We compare here the spectroscopic and electrochemical properties of the polymer, the repeat unit, and the separate carbazole donor and dithienylbenzothiadiazole acceptor moieties (CB and dTBT, respectively) in the solid state and in solutions of various polarity. The results are interpreted with the help of time-dependent density functional theory (TD-DFT) calculations. We identify the dominant electronic transitions responsible for the first two absorption bands in the “camel back” spectrum of PCDTBT as partial charge transfer transitions with significant delocalization in the directly excited states. The low bandgap, overall shape, and partial charge transfer character of the PCDTBT absorption spectrum originate from transitions in the dTBT unit. The attached CB moiety extends the conjugation length in CDTBT, rather than acting as a localized donor. Further electronic delocalization, leading to a relatively small reduction in bandgap, occurs upon polymerization. We use our finding of higher delocalization following excitation in the second absorption band to explain the increased yield of photogenerated charges from this band in PCDTBT solid thin films. Moreover, we point out the importance of initial delocalization in the functioning of bulk heterojunction solar cells. The results presented here are therefore not only highly important for a better understanding of donor–acceptor copolymers in general but can also potentially guide the strategic development of future photovoltaic materials.

Effective target tracking and obstacle avoidance strategies are essential to the success of unmanned aerial vehicle (UAV) missions. This paper describes a decentralized model-based predictive control to calculate the optimal UAV trajectory that will lead each UAV to the interception of a target at a desired time and with desired speed, heading and flight path angle, while avoiding dynamic ellipsoidal obstacles detected en route. Obstacle avoidance is based on the minimization of the UAV collision probability with all known obstacles on a future horizon, while ensuring that the collision probability with any given obstacle at each prediction step does not surpass a preset threshold. Cooperation between UAVs is possible by exchanging information about the obstacles they detect. To respect the arrival specifications, a virtual target is created and tracked. The virtual target moves at the desired speed and along a straight line that is correctly oriented to intercept the real target position at the desired arrival time. Arrival specifications are respected if tracking of the virtual target by the UAV is successful. Simulations are presented to demonstrate the effectiveness of the proposed approach. They also illustrate that cooperation can improve the UAV performance.

Irradiation of 2- and 4-xanthone acetic acid in aqueous buffer (pH 7.4) leads to efficient (Φ = 0.67 and 0.64, respectively) photodecarboxylation to give the corresponding methyl products, consistent with an intermediate benzylic carbanion. Fluorescence and laser flash photolysis (LFP) studies suggest singlet state reactivity, which is unusual for aromatic ketones. 3-Xanthone acetic acid is photoinert under the same conditions. The results suggest that the reactive xanthone acetic acids are promising precursors for carbanion-mediated photocages.

Objective: To provide updated data on the incidence, types, and demographics of laryngoceles in the adult population.Methods: We searched the medical archives of our institute for computed tomography (CT) studies acquired between January 1, 2007 and December 31, 2017 in which the term “laryngocele” appeared in the radiology reports. Two of the authors reviewed relevant images for the presence, type, distribution, and laterality of true laryngoceles. Demographic and clinical data were extracted from medical records and the incidence was calculated.Results: Laryngoceles were detected in 53 out of the 79 893 patients with relevant CT data, which equates to an incidence of 151 per 2.5 million (0.06:1000) patients per year. The male:female ratio was 3:1, average age was 60 (±18) years, and incidence peaked among patients in the sixth decade of life. Nine patients (17%) had known laryngeal cancer; however, the majority of the cohort did not have follow up clinic visits.Conclusion: Our study demonstrates that the incidence of laryngoceles is much greater than previously reported. In most cases, the diagnosis of a laryngocele was an incidental radiological finding. Male gender predilection and age at presentation are in agreement with previous reports. Association of laryngoceles with laryngeal cancer could not be calculated due to low rates of follow ups.Level of Evidence: 3.

Several letters to the editor are presented in response to articles in previous issues of "Harrowsmith Country Life" including "Picture Perfect Pickles" and "Wild Horse Country" in the October 2009 issue and "Our Internet Solution" in the August 2009 issue.