Tootfinder

Periodic Bipedal Gait Learning Using Reward Composition Based on a Novel Gait Planner for Humanoid Robots
Bolin Li, Linwei Sun, Xuecong Huang, Yuzhi Jiang, Lijun Zhu
https://arxiv.org/abs/2506.08416

Periodic Bipedal Gait Learning Using Reward Composition Based on a Novel Gait Planner for Humanoid Robots
This paper presents a periodic bipedal gait learning method using reward composition, integrated with a real-time gait planner for humanoid robots. First, we introduce a novel gait planner that incorporates dynamics to design the desired joint trajectory. In the gait design process, the 3D robot model is decoupled into two 2D models, which are then approximated as hybrid inverted pendulums (H-LIP) for trajectory planning. The gait planner operates in parallel in real time within the robot's lea…

🛡️ DAY 3 at GÉANT #SecurityDays | Thank you!
A huge thank you to 160 participants from 28 countries! With strong female representation and 63 unique organisations, Security Days was more than just an event—it was a community in action.
We closed with a thought-provoking plenary on #AI, digit…

k-Planar and Fan-Crossing Drawings and Transductions of Planar Graphs
Petr Hlin\v{e}n\'y, Jan Jedelsk\'y
https://arxiv.org/abs/2506.08585 https://

k-Planar and Fan-Crossing Drawings and Transductions of Planar Graphs
We introduce a two-way connection between FO transductions (logical transformations) of planar graphs, and a certain variant of fan-crossing (fan-planar) drawings of graphs which for bounded-degree graphs essentially reduces to being k-planar for fixed k. For graph classes, this connection allows to derive non-transducibility results from nonexistence of the said drawings and, conversely, from nonexistence of a transduction to derive nonexistence of the said drawings. For example, the class of …

Micro-Macro Modeling of Polymeric Fluids with Multi-Bead Polymer Chain
Xuelian Bao, Lidong Fang, Huaxiong Huang, Zilong Song, Shixin Xu
https://arxiv.org/abs/2506.08377

Micro-Macro Modeling of Polymeric Fluids with Multi-Bead Polymer Chain
This work extends the classical dumbbell (two-bead) model of polymer chains to a more detailed multi-bead representation, where each polymer chain consists of $N$ beads connected by $N-1$ springs. We develop a thermodynamically consistent micro-macro model based on the energy variational method to describe the coupled dynamics of polymer configurations and fluid flow. The resulting framework captures complex microscopic behaviors, such as bond stretching and alignment under flow, and links them…

Excluding an induced wheel minor in graphs without large induced stars
Mujin Choi, Claire Hilaire, Martin Milani\v{c}, Sebastian Wiederrecht
https://arxiv.org/abs/2506.08829

Excluding an induced wheel minor in graphs without large induced stars
We study a conjecture due to Dallard, Krnc, Kwon, Milanič, Munaro, Štorgel, and Wiederrecht stating that for any positive integer $d$ and any planar graph $H$, the class of all $K_{1,d}$-free graphs without $H$ as an induced minor has bounded tree-independence number. A $k$-wheel is the graph obtained from a cycle of length $k$ by adding a vertex adjacent to all vertices of the cycle. We show that the conjecture of Dallard et al. is true when $H$ is a $k$-wheel for any $k\geq 3$. Our proof us…

This https://arxiv.org/abs/2404.04218 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_csPL_…

Simplifying explicit subtyping coercions in a polymorphic calculus with effects
Algebraic effect handlers are becoming an increasingly popular way of structuring effectful computations, and their performance is often a concern. One of the proposed approaches towards efficient compilation is tracking effect information through explicit subtyping coercions. However, in the presence of polymorphism, these coercions are compiled into additional arguments of compiled functions, incurring significant overhead. In this paper, we present a polymorphic effectful calculus, identify …

Im kalten Krieg war die Behauptung: „Marktwirtschaft ist effizienter als Planwirtschaft, deswegen haben wir all die schönen Dinge und die da drüben müssen auf ihren Trabi 20 Jahre warten. Und deswegen ist es ok, wenn Unternehmer mehr davon profitieren, weil es letztlich für alle besser ist.“
Und irgendwie wurde daraus ein: „Es ist moralisch richtig, wenn Firmeneigner und Aktionäre stinkreich werden, während sich dein Leben nicht verbessert.“
Bei Ersterem nehmen wir die kapitalist…

Coulomb Branch and Integrability
Frank Coronado, Shota Komatsu, Konstantin Zarembo
https://arxiv.org/abs/2506.07222 https://arxiv.org…

Coulomb Branch and Integrability
We study one-point functions of non-BPS single-trace operators on the Coulomb branch of planar $\mathcal{N}=4$ supersymmetric Yang-Mills theory. Holography relates them to overlaps between on-shell closed string states and a boundary state describing a probe D3-brane in $AdS_5\times S^{5}$. Assuming that the D-brane preserves integrability, we formulate and solve integrable bootstrap equations satisfied by the boundary state at finite 't Hooft coupling. This leads to a closed-form determinant e…

Elastic turbulence in highly entangled polymers and wormlike micelles
Theo A. Lewy, Suzanne M. Fielding, Peter D. Olmsted, Rich R. Kerswell
https://arxiv.org/abs/2506.07146

Elastic turbulence in highly entangled polymers and wormlike micelles
We show theoretically that an initially homogeneous planar Couette flow of a concentrated polymeric fluid is linearly unstable to the growth of two-dimensional (2D) perturbations, within two widely used constitutive models: the Johnson-Segalman model and the Rolie-Poly model. We perform direct nonlinear simulations of both models in 2D to show that this instability leads to a state of elastic turbulence comprising several narrow shear bands that dynamically coalesce, split and interact. Importa…

Thermodynamics of microphase separation in a swollen, strain-stiffening polymer network
Carla Fern\'andez-Rico, Robert W. Style, Stefanie Heyden, Shichen Wang, Peter D. Olmsted, Eric R. Dufresne
https://arxiv.org/abs/2506.08958

Thermodynamics of microphase separation in a swollen, strain-stiffening polymer network
Elastic MicroPhase Separation (EMPS) provides a simple route to create soft materials with homogeneous microstructures by leveraging the supersaturation of crosslinked polymer networks with liquids. At low supersaturation, network elasticity stabilizes a uniform mixture, but beyond a critical threshold, metastable microphase-separated domains emerge. While previous theories have focused on describing qualitative features about the size and morphology of these domains, they do not make quantitat…