Toward Understanding Key Estimation in Learning Robust Humanoid Locomotion

Accurate state estimation plays a critical role in ensuring the robust control of humanoid robots, particularly in the context of learning-based control policies for legged robots. However, there is a notable gap in analytical research concerning estimations. Therefore, we endeavor to further understand how various types of estimations influence the decision-making processes of policies. In this paper, we provide quantitative insight into the effectiveness of learned state estimations, employing saliency analysis to identify key estimation variables and optimize their combination for humanoid locomotion tasks. Evaluations assessing tracking precision and robustness are conducted on comparative groups of policies with varying estimation combinations in both simulated and real-world environments. Results validated that the proposed policy is capable of crossing the sim-to-real gap and demonstrating superior performance relative to alternative policy configurations

A Public Key Cryptosystem Based on Non-abelian Finite Groups

Abstract We present a new approach to designing public-key cryptosystems, based on covers and logarithmic signatures of nonabelian finite groups. Initially, we describe a generic version of the system for a large class of groups. We then propose a class of 2-groups and argue heuristically about the system's security. The system is scalable, and the proposed underlying group, represented as a matrix group, affords significant space and time efficiency

Modulation of the effects of class Ib antiarrhythmics on cardiac NaV1.5-encoded channels by accessory NaVβ subunits

Native myocardial voltage-gated sodium (NaV) channels function in macromolecular complexes comprising a pore-forming (α) subunit and multiple accessory proteins. Here, we investigated the impact of accessory NaVβ1 and NaVβ3 subunits on the functional effects of 2 well-known class Ib antiarrhythmics, lidocaine and ranolazine, on the predominant NaV channel α subunit, NaV1.5, expressed in the mammalian heart. We showed that both drugs stabilized the activated conformation of the voltage sensor of domain-III (DIII-VSD) in NaV1.5. In the presence of NaVβ1, the effect of lidocaine on the DIII-VSD was enhanced, whereas the effect of ranolazine was abolished. Mutating the main class Ib drug-binding site, F1760, affected but did not abolish the modulation of drug block by NaVβ1/β3. Recordings from adult mouse ventricular myocytes demonstrated that loss of Scn1b (NaVβ1) differentially affected the potencies of lidocaine and ranolazine. In vivo experiments revealed distinct ECG responses to i.p. injection of ranolazine or lidocaine in WT and Scn1b-null animals, suggesting that NaVβ1 modulated drug responses at the whole-heart level. In the human heart, we found that SCN1B transcript expression was 3 times higher in the atria than ventricles, differences that could, in combination with inherited or acquired cardiovascular disease, dramatically affect patient response to class Ib antiarrhythmic therapies

Unusual activity of rationally designed cobalt phosphide/oxide heterostructure composite for hydrogen production in alkaline medium.

Design and development of an efficient, nonprecious catalyst with structural features and functionality necessary for driving the hydrogen evolution reaction (HER) in an alkaline medium remain a formidable challenge. At the root of the functional limitation is the inability to tune the active catalytic sites while overcoming the poor reaction kinetics observed under basic conditions. Herein, we report a facile approach to enable the selective design of an electrochemically efficient cobalt phosphide oxide composite catalyst on carbon cloth (CoP-CoxOy/CC), with good activity and durability toward HER in alkaline medium (η10= -43 mV). Theoretical studies revealed that the redistribution of electrons at laterally dispersed Co phosphide/oxide interfaces gives rise to a synergistic effect in the heterostructured composite, by which various Co oxide phases initiate the dissociation of the alkaline water molecule. Meanwhile, the highly active CoP further facilitates the adsorption-desorption process of water electrolysis, leading to extremely high HER activity

Enumeration of Certain Binary Vectors

In 1986, W. S. Griffith [2] proposed a reliability model and described a Markov chain approach for computing the reliability in the system. F. K. Hwang and S. Papastavridis [4] gave a closed-form formula for this reliability in 1991, by counting the number of n\Gammadimensional binary vectors containing exactly k non-overlapping m-tuples of consecutive ones. In 1988, T. M. Apostol [1] established recursive formulas and a generating function for a related problem, the enumeration of n\Gammadimensional binary vectors containing exactly k isolated m-tuples of consecutive ones. In this paper we study two interrelated elementary enumerator functions in terms of which we are able to address the two enumeration problems mentioned above. This enables us to provide a unified approach to deriving closed-form formulas for both problems, and provides solutions to finer enumeration problems. We extend our results to the case of cyclic binary vectors, and briefly discuss the number of cyclic ordere..

The Number of Classes of Choice Functions under Permutation Equivalence

A choice function f of an n\Gammaset X is a function whose domain is the power set P(X), and whose range is X, such that f(A) 2 A for each A ` X. If k is a fixed positive integer, k n, by a k-restricted choice function we mean the restriction of some choice function to the collection of k\Gammasubsets of X. The symmetric group SX acts, by natural extension on the respective collections C(X) of choice functions, and C k (X) of k\Gammarestricted choice functions of X. In this paper we address the problem of finding the number of orbits in the two actions, and give closed form formulas for the respective numbers. This work was supported in part by NSA grant MSFPF-95-G-091, and by CCIS -- Univ. of Nebraska - Lincoln y This work was supported in part by CCIS -- Univ. of Nebraska - Lincoln 1 Introduction A choice function f on an n\Gammaset X is defined to be a function whose domain is the collection of all subsets of X, and whose range is X, such that for each subset A of X, f(A)..