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1. On the Benefits of Traffic “Reprofiling” the Multiple Hops Case—Part I

   https://doi.org/10.1109/TNET.2024.3392030  

   Qiu, Jiaming; Song, Jiayi; Guérin, Roch; Sariowan, Henry (August 2024, IEEE/ACM Transactions on Networking)

   This paper considers networks where user traffic is regulated through deterministic traffic profiles, e.g., token buckets, and requires hard delay bounds. The network's goal is to minimize the resources it needs to meet those bounds. The paper explores how reprofiling, i.e., proactively modifying how user traffic enters the network, can be of benefit. Reprofiling produces "smoother" flows but introduces an up-front access delay that forces tighter network delays. The paper explores this trade-off and demonstrates that, unlike what holds in the single-hop case, reprofiling can be of benefit even when "optimal" schedulers are available at each hop. 

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2. The Influence of Shear on Deep Convection Initiation. Part I: Theory

   https://doi.org/10.1175/JAS-D-21-0145.1  

   Peters, John_M; Morrison, Hugh; Nelson, T_Connor; Marquis, James_N; Mulholland, Jake_P; Nowotarski, Christopher_J (June 2022, Journal of the Atmospheric Sciences)

   Abstract This article introduces a novel hypothesis for the role of vertical wind shear (“shear”) in deep convection initiation (DCI). In this hypothesis, initial moist updrafts that exceed a width and shear threshold will “root” within a progressively deeper steering current with time, increase their low-level cloud-relative flow and inflow, widen, and subsequently reduce their susceptibility to entrainment-driven dilution, evolving toward a quasi-steady self-sustaining state. In contrast, initial updrafts that do not exceed the aforementioned thresholds experience suppressed growth by shear-induced downward pressure gradient accelerations, will not root in a deep-enough steering current to increase their inflow, will narrow with time, and will succumb to entrainment-driven dilution. In the latter case, an externally driven lifting mechanism is required to sustain deep convection, and deep convection will not persist in the absence of such lifting mechanism. A theoretical model is developed from the equations of motion to further explore this hypothesis. The model indicates that shear generally suppresses DCI, raising the initial subcloud updraft width that is necessary for it to occur. However, there is a pronounced bifurcation in updraft growth in the model after the onset of convection. Sufficiently wide initial updrafts grow and eventually achieve a steady state. In contrast, insufficiently wide initial updrafts shrink with time and eventually decay completely without external support. A sharp initial updraft radius threshold discriminates between these two outcomes. Thus, consistent with our hypothesis and observations, shear inhibits DCI in some situations, but facilitates it in others. 

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3. Mutual Learning: Part I - Learning Automata

   https://doi.org/10.23919/ACC.2019.8814751  

   Narendra, Kumpati S.; Mukhopadhyay, Snehasis (July 2019, 2019 American Control Conference (ACC))
4. Mutual Learning: Part I-Learning Automata

   https://doi.org/10.23919/ACC.2019.8814751  

   Narendra, K.S.; Mukhopadhyay, S. (November 2019, 2019 American Control Conference (ACC). IEEE.)
5. Sliding friction of a pillar array interface: part I

   https://doi.org/10.1039/d3sm01323e  

   Kaur, Jasreen; Xiao, Xuemei; Khripin, Constantine; Hui, Chung-Yuen; Jagota, Anand (February 2024, Soft Matter)

   Biology is replete with examples, at length scales ranging from the molecular (ligand–receptor binding) to the mesoscopic scale (wing arresting structures on dragonflies) where shape-complementary surfaces are used to control interfacial mechanical properties such as adhesion, friction, and contact compliance. Related bio-inspired and biomimetic structures have been used to achieve unique interfacial properties such as friction and adhesion enhancement, directional and switchable properties. The ability to tune friction by altering surface structures offers advantages in various fields, such as soft robotics and tire manufacturing. Here, we present a study of friction between polydimethylsiloxane (PDMS) samples with surfaces patterned with pillar-arrays. When brought in contact with each other the two samples spontaneously produce a Moire´ pattern that can also be represented as an array of interfacial dislocations that depends on interfacial misorientation and lattice spacing. Misorientation alone produces an array of screw dislocations, while lattice mismatch alone produces an array of edge dislocations. Relative sliding motion is accompanied by interfacial glide of these patterns. The frictional force resisting dislocation glide arises from periodic single pillar–pillar contact and sliding. We study the behavior of pillar–pillar contact with larger (millimeter scale) pillar samples. Inter-pillar interaction measurements are combined with a geometric model for relative sliding to calculate frictional stress that is in good agreement with experiments. 

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