Positive Eigen-Pair of Dual Operator and Applications in Two-Player Game Control

Vo Viet Tri

doi:10.46719/dsa20213016

Policy adaptation for vehicle routing

AI Communications ◽

10.3233/aic-201577 ◽

2020 ◽

pp. 1-15

Author(s):

Tristan Cazenave ◽

Jean-Yves Lucas ◽

Thomas Triboulet ◽

Hyoseok Kim

Keyword(s):

Vehicle Routing ◽

Search Algorithm ◽

Daily Basis ◽

Electric Utility ◽

Routing Problem ◽

Utility Company ◽

Standard Problem ◽

Policy Adaptation ◽

Monte Carlo Search ◽

Player Game

Nested Rollout Policy Adaptation (NRPA) is a Monte Carlo search algorithm that learns a playout policy in order to solve a single player game. In this paper we apply NRPA to the vehicle routing problem. This problem is important for large companies that have to manage a fleet of vehicles on a daily basis. Real problems are often too large to be solved exactly. The algorithm is applied to standard problem of the literature and to the specific problems of EDF (Electricité De France, the main French electric utility company). These specific problems have peculiar constraints. NRPA gives better result than the algorithm previously used by EDF.

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Constraints on quasinormal modes and bounds for critical points from pole-skipping

Journal of High Energy Physics ◽

10.1007/jhep03(2021)265 ◽

2021 ◽

Vol 2021 (3) ◽

Author(s):

Navid Abbasi ◽

Matthias Kaminski

Keyword(s):

Critical Points ◽

Thermal State ◽

Quasinormal Modes ◽

Scalar Perturbation ◽

Black Brane ◽

Massive Scalar ◽

Dual Operator ◽

Conformal Dimension ◽

Scalar Operator ◽

First Time

Abstract We consider a holographic thermal state and perturb it by a scalar operator whose associated real-time Green’s function has only gapped poles. These gapped poles correspond to the non-hydrodynamic quasinormal modes of a massive scalar perturbation around a Schwarzschild black brane. Relations between pole-skipping points, critical points and quasinormal modes in general emerge when the mass of the scalar and hence the dual operator dimension is varied. First, this novel analysis reveals a relation between the location of a mode in the infinite tower of quasinormal modes and the number of pole-skipping points constraining its dispersion relation at imaginary momenta. Second, for the first time, we consider the radii of convergence of the derivative expansions about the gapped quasinormal modes. These convergence radii turn out to be bounded from above by the set of all pole-skipping points. Furthermore, a transition between two distinct classes of critical points occurs at a particular value for the conformal dimension, implying close relations between critical points and pole-skipping points in one of those two classes. We show numerically that all of our results are also true for gapped modes of vector and tensor operators.

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Analysis of Injuries and Pitching Performance Between Major League Baseball and Nippon Professional Baseball: A 2-Team Comparison Between 2015 to 2019

Orthopaedic Journal of Sports Medicine ◽

10.1177/23259671211008810 ◽

2021 ◽

Vol 9 (5) ◽

pp. 232596712110088

Author(s):

Ryan L. Crotin ◽

Toshimasa Yanai ◽

Peter Chalmers ◽

Kenneth B. Smale ◽

Brandon J. Erickson ◽

...

Keyword(s):

Los Angeles ◽

Major League Baseball ◽

Professional Baseball ◽

Injury Incidence ◽

Mechanism Of Injury ◽

Research Collaborations ◽

Minor League ◽

Major League ◽

Player Game ◽

And Performance

Background: There has been minimal research investigating injury and pitching performance differences between Major League Baseball (MLB) and other professional leagues. Purpose/Hypothesis: This 2-team comparison between MLB and Japan’s Nippon Professional Baseball (NPB) involved affiliated players over 5 years. We hypothesized that teams would differ in the injury incidence, mechanism of injury, pitch velocity, and pitch type usage. Study Design: Descriptive epidemiology study. Methods: Between 2015 and 2019, pitching data as well as injury statistics for the highest level and minor league affiliates of the Los Angeles Angels (MLB) and the Hiroshima Toyo Carp (NPB) were reviewed for significant differences in the injury prevalence, injury type, mechanism of injury, and days missed. In total, 3781 MLB and 371 NPB injuries were studied. Results: MLB-affiliated players were significantly younger, taller, and heavier ( P < .001) than were NPB-affiliated players. MLB-affiliated pitchers threw faster than did their NPB counterparts ( P = .026). MLB minor league pitchers threw more curveballs than did NPB minor league pitchers ( P = .004), and MLB minor league relief pitchers threw more sliders than did NPB minor league relief pitchers ( P = .02). The MLB team had a 3.7-fold higher incidence of injuries versus the NPB team (0.030 vs 0.008 injuries per player-game, respectively) as well as more repeat injuries, with fewer days missed per injury (15.8 ± 54.7 vs 36.2 ± 55.1 days, respectively; P < .001). The MLB team also had a higher percentage of injuries that were throwing related ( P < .001), were contact related ( P < .001), and occurred outside of competition ( P < .001) compared with the NPB team. Conclusion: This is the first empirical study examining injury trends and pitching characteristics between MLB and NPB athletes. MLB-affiliated pitchers threw faster and relied more on breaking pitches in comparison with NPB-affiliated pitchers. From injury data, MLB players were younger, taller, and heavier with a higher percentage of throwing-related injuries, contact injuries, and injuries sustained outside of competition. Overall, the MLB team indicated a 3.7-fold higher rate of reported injuries with fewer days missed per injury than did the NPB team. Competitive conditions are distinctly different between MLB and NPB, and thus, more extensive research collaborations in the future can identify best practices to advance health and performance for both leagues.

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Online Ramsey Games in Random Graphs

Combinatorics Probability Computing ◽

10.1017/s0963548308009632 ◽

2009 ◽

Vol 18 (1-2) ◽

pp. 271-300 ◽

Cited By ~ 16

Author(s):

MARTIN MARCINISZYN ◽

RETO SPÖHEL ◽

ANGELIKA STEGER

Keyword(s):

Lower Bound ◽

Random Graphs ◽

Empty Graph ◽

Current Graph ◽

Player Game ◽

Monochromatic Copy

Consider the following one-player game. Starting with the empty graph onnvertices, in every step a new edge is drawn uniformly at random and inserted into the current graph. This edge has to be coloured immediately with one ofravailable colours. The player's goal is to avoid creating a monochromatic copy of some fixed graphFfor as long as possible. We prove a lower bound ofnβ(F,r)on the typical duration of this game, where β(F,r) is a function that is strictly increasing inrand satisfies limr→∞β(F,r) = 2 − 1/m2(F), wheren2−1/m2(F)is the threshold of the corresponding offline colouring problem.

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