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With the kinetic freeze-out nucleons and antinucleons obtained from the quark combination model, we study the production of light nuclei and antinuclei in the (anti-)nucleon coalescence mechanism in relativistic heavy ion collisions. We derive analytic formulas of the momentum distributions of different light nuclei and apply them to compute transverse momentum ($p_T$) spectra of (anti-)deuterons ($d$, $\bar d$) and (anti-)tritons ($t$, $\bar t$) in Au-Au collisions at $\sqrt{s_{NN}}=$7.7, 11.5, 19.6, 27, 39, 54.4 GeV. We find that the experimental data available for these $p_T$ spectra can be well reproduced. We further study the yields and yield ratios of different light (anti-)nuclei and naturally explain their interesting behaviors as a function of the collision energy. We especially point out that the multi-particle yield ratio $tp/d^2$ should be carefully corrected from hyperon weak decays for protons to probe the production characteristics of light nuclei. All of our results show that the coalescence mechanism for (anti-)nucleons plays a dominant role for the production of light nuclei and antinuclei at the RHIC beam energy scan energies., Comment: 14 pages,10 figures

Motion feature is of great significance for blob targets recognition, behavior analysis and threat estimation in active sonar echographs. Hence, it is desirable to access the space-time variation of echo intensity on each spatial-temporal resolution cell from the sonar echographs sequence. Then the subtle motion information of the potential blob targets can be accurately characterized. This idea has been conduced in optical image sequences by solving an motion optical flow field (MOFF) function. Nonetheless, due to the sparkle of the sonar echograph sequences, and strong interferences caused by wake and cavitation noise of fast-moving ship in harbor environments, the constraints underlying the traditional motion optical flow function that is couples the brightness constancy constant along time dimension of each echo intensity points and the motion field spatial smoothness does not hold in our case. Hence, this paper presents a new motion acoustic flow field (MAFF) function and its solving strategy to accurately characterize the subtle motion information of blob targets in active sonar echographs of harbor environments. Experiments on a series of cooperative targets in real-world harbor environments demonstrate the efficacy of our proposed MAFF.

Games and simulators can be a valuable platform to execute complex multi-agent, multiplayer, imperfect information scenarios with significant parallels to military applications: multiple participants manage resources and make decisions that command assets to secure specific areas of a map or neutralize opposing forces. These characteristics have attracted the artificial intelligence (AI) community by supporting development of algorithms with complex benchmarks and the capability to rapidly iterate over new ideas. The success of artificial intelligence algorithms in real-time strategy games such as StarCraft II have also attracted the attention of the military research community aiming to explore similar techniques in military counterpart scenarios. Aiming to bridge the connection between games and military applications, this work discusses past and current efforts on how games and simulators, together with the artificial intelligence algorithms, have been adapted to simulate certain aspects of military missions and how they might impact the future battlefield. This paper also investigates how advances in virtual reality and visual augmentation systems open new possibilities in human interfaces with gaming platforms and their military parallels., Comment: Preprint submitted to the Journal of Defense Modeling and Simulation (JDMS) for peer review

We find signals of quark combination at hadronization from the experimental data of $p_{T}$ spectra of hadrons at mid-rapidity in $pp$ collisions at $\sqrt{s}=200$ GeV. The first is the constituent quark number scaling property for $p_{T}$ spectra of $\Omega^{-}$ and $\phi$ and that for $p_{T}$ spectra of $p$ and $\rho^{0}$. The second is that $p_{T}$ spectra of $\Lambda$, $\Xi^{-}$, and $K^{*0}$ can be self-consistently described using the spectrum of strange quarks from $\phi$ data and that of up/down quarks from $p$ data in the equal-velocity combination mechanism. The third is that experimental data for $p_{T}$ spectrum of $D^{*+}$ are also well described using the spectrum of up/down quarks from $p$ data and that of charm quarks from perturbative QCD calculations. These results indicate a similarity between hadron production in $pp$ collisions at $\sqrt{s}=200$ GeV and that at LHC energies. We predict $p_{T}$ spectra of single-charm hadrons and their spectrum ratios. We suggest systematic measurements in $pp$ collisions at $\sqrt{s}=200$ GeV in future so as to better understand the property of small parton system created in $pp$ collisions at different collision energies., Comment: 6 pages, 5 figures