Thompson sampling based Monte-Carlo planning in POMDPs

Monte-Carlo tree search (MCTS) has been drawinggreat interest in recent years for planning under uncertainty. One of the key challenges is the tradeoffbetween exploration and exploitation. To addressthis, we introduce a novel online planning algorithmfor large POMDPs using Thompson sampling basedMCTS that balances between cumulative and simple regrets.The proposed algorithm — Dirichlet-Dirichlet-NormalGamma based Partially Observable Monte-Carlo Planning (D2NG-POMCP) — treats the accumulatedreward of performing an action from a beliefstate in the MCTS search tree as a random variable followingan unknown distribution with hidden parameters.Bayesian method is used to model and infer theposterior distribution of these parameters by choosingthe conjugate prior in the form of a combination of twoDirichlet and one NormalGamma distributions. Thompsonsampling is exploited to guide the action selection inthe search tree. Experimental results confirmed that ouralgorithm outperforms the state-of-the-art approacheson several common benchmark problems

Ground vibration propagation and attenuation of vibrating compaction

When a high-power vibrating roller compact the subgrade, the vibration wave will quickly propagate along the surface of the subgrade and generate hazards to surrounding environment and structure. To study the vibration propagation rules of the roller, the vibration acceleration of the high-power vibrating roller was measured on the surface of the rock subgrade, coarse-grained soil subgrade and fine-grained soil subgrade. The respective relations between vibration acceleration and the distance from a vibration source in the vertical, horizontal radial and horizontal circumferential direction have been discovered. The research results show that the vibration peak frequency generated by the vibrating roller on the subgrade approximates vibration frequency. The vibration effective influence distance varies from 10m to14m, and the horizontal radial vibration is greater than that of vertical and horizontal circumferential direction. The vibration of the rock subgrade attenuates the most slowly and propagates the most remotely

A New Model of Ultracapacitors Based on Fractal Fundamentals

An intuitive model is proposed in this paper to describe the electrical behavior of certain ultracapacitors. The model is based on a simple expression that can be fully characterized by five real numbers. In this paper, the measured impedances of three ultracapacitors as a function of frequency are compared to model results. There is good agreement between the model and measurements. Results presented in a previous study are also reviewed and the paper demonstrates that those results are also consistent with the newly described model

Sox10+ adult stem cells contribute to biomaterial encapsulation and microvascularization.

Implanted biomaterials and biomedical devices generally induce foreign body reaction and end up with encapsulation by a dense avascular fibrous layer enriched in extracellular matrix. Fibroblasts/myofibroblasts are thought to be the major cell type involved in encapsulation, but it is unclear whether and how stem cells contribute to this process. Here we show, for the first time, that Sox10+ adult stem cells contribute to both encapsulation and microvessel formation. Sox10+ adult stem cells were found sparsely in the stroma of subcutaneous loose connective tissues. Upon subcutaneous biomaterial implantation, Sox10+ stem cells were activated and recruited to the biomaterial scaffold, and differentiated into fibroblasts and then myofibroblasts. This differentiation process from Sox10+ stem cells to myofibroblasts could be recapitulated in vitro. On the other hand, Sox10+ stem cells could differentiate into perivascular cells to stabilize newly formed microvessels. Sox10+ stem cells and endothelial cells in three-dimensional co-culture self-assembled into microvessels, and platelet-derived growth factor had chemotactic effect on Sox10+ stem cells. Transplanted Sox10+ stem cells differentiated into smooth muscle cells to stabilize functional microvessels. These findings demonstrate the critical role of adult stem cells in tissue remodeling and unravel the complexity of stem cell fate determination

USING AUXILIARY CONTACT FOR THE DISPOSITION OF DROP-OUT FUSE FAULTS ---A NEW RESCUE MEASURES TO SHORTEN THE RESTORATION TIME AND INCREASE THE POWER SUPPLY RELIABILITY IN FAULT RESCUE

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Changes in Life's Essential 8 and risk of cardiovascular disease in Chinese people

Background The American Heart Association recently released an updated algorithm for evaluating cardiovascular health-Life's Essential 8 (LE8). However, the associations between changes in LE8 score over time and risk of cardiovascular disease (CVD) remain unclear. Methods We investigated associations between 6-year changes (2006-12) in LE8 score and risk of subsequent CVD events (2012-20) among 53 363 Chinese men and women from the Kailuan Study, who were free from CVD in 2012. The LE8 score was calculated based on eight components: diet quality, physical activity, smoking status, sleep health, body mass index, blood lipids, blood glucose and blood pressure. Multivariable-adjusted Cox proportional-hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results We documented 4281 incident CVD cases during a median of 7.7 years of follow-up. Compared with participants whose LE8 scores remained stable in a 6-year period, those with the large increases of LE8 score over the 6-year period had a lower risk of CVD, heart disease and stroke in the subsequent 8 years [HRs and 95% CIs: 0.67 (0.64, 0.70) for CVD, 0.65 (0.61, 0.69) for heart disease, 0.71 (0.67, 0.76) for stroke, all P-trend < 0.001]. Conversely, those with the large decreases of LE8 score had 47%, 51% and 41% higher risk for CVD, heart disease and stroke, respectively. These associations were consistent across the subgroups stratified by risk factors. Conclusions Improving LE8 score in a short- and moderate-term was associated with a lower CVD risk, whereas decreased LE8 score over time was associated with a higher risk