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1. dV/dt Impact on Turn-to-Turn Overvoltage Distribution in Motor Windings

   https://doi.org/10.1109/EMCSIPI50001.2023.10241617  

   Azadeh, Yalda; Mirza, Abdul Basit; Choksi, Kushan; Zhang, Xiaolong; Luo, Fang; Haran, Kiruba S (July 2023, IEEE)
2. Control of turn-to-turn contact resistivity in no-insulation REBCO coils

   https://doi.org/10.1088/1361-6668/ae8b32  

   Lu, Jun; Kim, Kwangmin; Dixon, Iain; Deterding, Justin; Marks, Emsley; Jarvis, Brent; Markiewicz, Denis; Bai, Hongyu; Bird, Mark (July 2026, Superconductor Science and Technology)

   Abstract No-insulation (NI) REBCO magnets with optimized contact resistivity feature short ramp times and low ramp losses while maintaining the advantages of NI coils with high engineering current density and tolerance for defects in the REBCO conductor. Control of the turn-to-turn contact resistivity (ρ_c) is key to NI technology.ρ_cmust be sufficiently high to prevent a large transient current, which could result in high mechanical stress during magnet quenches. Meanwhile it must be lower than the quench propagation limit to avoid conductor burn-out during a quench. Therefore, it is critical to controlρ_cwithin a suitable range of values which is usually coil specific. Previously, we discovered thatρ_cbetween two REBCO tapes with a stainless steel interlayer decreases dramatically with contact pressure cycling by up to three orders of magnitude. This drastic change makes it impossible to design a suitableρ_cvalue for a stainless steel co-wound NI magnet. In this work, we first present methods for mitigatingρ_cpressure cycling sensitivity. We found that by adding conductive fillers, such as conductive paste or epoxy, theρ_cload cycling sensitivity is largely mitigated. For dry-wound coils,ρ_cload cycling sensitivity is mitigated by coating REBCO tape with a layer of 2–3µm of PbSn solder. In addition,ρ_ccan be controlled by oxidizing the stainless steel co-wind tape by heating stainless steel tapes at different temperatures in air. Using above methods, short sample tests showed thatρ_cwas controlled to prescribed values of 1000 and 5000µΩ-cm²and was not sensitive to contact pressure cycling up to 30 000 cycles at 4.2 K. The newρ_ccontrol method was applied to a 6 double-pancake test coil which was tested at 4.2 K. Theρ_cin this test coil was comparable with the short sample results. This demonstrated the ability of this new method to controlρ_cin large coils. Moreover, we propose a method of measuring coil’sρ_cby the decay time of coil’s inductive voltage. 

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3. Turn Constrained Shortest Path

   https://doi.org/10.1109/HONET59747.2023.10374669  

   Allani, Amogh; Yang, KwangSoo (December 2023, International Conference on Smart Communities: Improving Quality of Life using AI, Robotics and IoT (HONET))

   Given a transportation network, a source node s, a destination node t , and the number of maximum possible turnings b , the Turn-Constrained Shortest Path (TCSP) problem is to find the route that minimizes the travel distance and meets the turn-constraint. The TCSP problem is important for societal applications such as shipping and logistics, emergency route planning, and traffic management services. We propose novel approaches for TCSP to meet the turn-constraint while minimizing the travel distance for the vehicle route. Experiments using real-world datasets demonstrated that the proposed algorithms can minimize the travel distance and meet the turn-constraint; furthermore, it has comparable solution quality to the unconstrained shortest path and significantly reduces the computational cost. 

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4. Are Turn-by-Turn Navigation Systems of Regular Vehicles Ready for Edge-Assisted Autonomous Vehicles?

   https://doi.org/10.1109/TITS.2023.3275367  

   Atik, Syeda Tanjila; Brocanelli, Marco; Grosu, Daniel (May 2023, IEEE Transactions on Intelligent Transportation Systems)
5. Why do hybrids turn down sex?

   https://doi.org/10.1093/evolut/qpad129  

   Fyon, Frédéric; Berbel-Filho, Waldir Miron; Schlupp, Ingo; Wild, Geoff; Úbeda, Francisco (July 2023, Evolution)

   Orive, Maria E; Chapman, Tracey (Ed.)

   Abstract Asexual reproduction is ancestral in prokaryotes; the switch to sexuality in eukaryotes is one of the major transitions in the history of life. The study of the maintenance of sex in eukaryotes has raised considerable interest for decades and is still one of evolutionary biology’s most prominent question. The observation that many asexual species are of hybrid origin has led some to propose that asexuality in hybrids results from sexual processes being disturbed because of incompatibilities between the two parental species’ genomes. However, in some cases, failure to produce asexual F1s in the lab may indicate that this mechanism is not the only road to asexuality in hybrid species. Here, we present a mathematical model and propose an alternative, adaptive route for the evolution of asexuality from previously sexual hybrids. Under some reproductive alterations, we show that asexuality can evolve to rescue hybrids’ reproduction. Importantly, we highlight that when incompatibilities only affect the fusion of sperm and egg’s genomes, the two traits that characterize asexuality, namely unreduced meiosis and the initiation of embryogenesis without the incorporation of the sperm’s pronucleus, can evolve separately, greatly facilitating the overall evolutionary route. Taken together, our results provide an alternative, potentially complementary explanation for the link between asexuality and hybridization. 

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