Simultaneous Feature and Body-Part Learning for Real-Time Robot Awareness of Human Behaviors

Robot awareness of human actions is an essential research problem in robotics with many important real-world applications, including human-robot collaboration and teaming. Over the past few years, depth sensors have become a standard device widely used by intelligent robots for 3D perception, which can also offer human skeletal data in 3D space. Several methods based on skeletal data were designed to enable robot awareness of human actions with satisfactory accuracy. However, previous methods treated all body parts and features equally important, without the capability to identify discriminative body parts and features. In this paper, we propose a novel simultaneous Feature And Body-part Learning (FABL) approach that simultaneously identifies discriminative body parts and features, and efficiently integrates all available information together to enable real-time robot awareness of human behaviors. We formulate FABL as a regression-like optimization problem with structured sparsity-inducing norms to model interrelationships of body parts and features. We also develop an optimization algorithm to solve the formulated problem, which possesses a theoretical guarantee to find the optimal solution. To evaluate FABL, three experiments were performed using public benchmark datasets, including the MSR Action3D and CAD-60 datasets, as well as a Baxter robot in practical assistive living applications. Experimental results show that our FABL approach obtains a high recognition accuracy with a processing speed of the order-of-magnitude of 10e4 Hz, which makes FABL a promising method to enable real-time robot awareness of human behaviors in practical robotics applications.Comment: 8 pages, 6 figures, accepted by ICRA'1

Effects of tidally enhanced stellar wind on the horizontal branch morphology of globular clusters

Metallicity is the first parameter to influence the horizontal branch (HB) morphology of globular clusters (GCs). It has been found, however, that some other parameters may also play an important role in affecting the morphology. While the nature of these important parameters remains unclear, they are believed to be likely correlated with wind mass-loss of red giants, since this mass loss determines their subsequent locations on the HB. Unfortunately, the mass loss during the red giant stages of the stellar evolution is poorly understood at present. The stellar winds of red giants may be tidally enhanced by companion stars if they are in binary systems. We investigate evolutionary consequences of red giants in binaries by including tidally enhanced stellar winds, and examine the effects on the HB morphology of GCs. We find that red, blue, and extreme horizontal branch stars are all produced under the effects of tidally enhanced stellar wind without any additional assumptions on the mass-loss dispersion. Furthermore, the horizontal branch morphology is found to be insensitive to the tidal enhancement parameter, Bw. We compare our theoretical results with the observed horizontal branch morphology of globular cluster NGC 2808, and find that the basic morphology of the horizontal branch can be well reproduced. The number of blue horizontal branch stars in our calculations, however, is lower than that of NGC 2808.Comment: 7 pages, 4 figures, 2 tables, accepted for publication in Astronomy & Astrophysic

Survivability of probiotics in symbiotic low fat buffalo milk yogurt

In present study, symbiotic low fat buffalo milk yogurt prototypes (plain and blueberry) were developed using a commercial starter containing probiotics. Samples were analyzed for physicochemical and microbiological properties, and the survivability of probiotics during 10 weeks of storage. Gross composition results were: total solids 11.60 ± 0.58 and 17.12 ± 0.36%, ash 0.82 ± 0.06 and 0.78 ± 0.02%, protein 4.49 ± 0.31 and 4.16 ± 0.11%, fat 0.68 ± 0.03 and 0.55 ± 0.05%, carbohydrates 5.68 ± 0.18 and 11.38 ± 0.18% for plain and blueberry flavored samples, respectively. Mineral contents (mg/g) were: Calcium 1.97 ± 0.20 and 1.72 ± 0.06, magnesium 1.63 ± 0.02 and 1.69 ± 0.01, zinc 0.07 ± 0.01 and 0.07 ± 0.00, sodium 0.87 ± 0.15 and 0.94 ± 0.12 for the plain and blueberry flavored yogurt respectively. The values of pH, titratable acidity and viscosity ranged from 4.34 to 4.01 and 4.42 to 3.70, 0.96 to 1.13% and 0.94 to 1.30%, 1.40 to 1.67 and 2.15 to 1.56 Pa.s for the plain and blueberry flavored yogurts respectively. The initial population of Bifidobacterium spp. and Lactobacillus casei were above 108 CFU/g for both the plain and blueberry flavored yogurts. Lactobacillus acidophilus was viable only for the first two weeks; however, Bifidobacterium spp and L. casei remained viable (>106 CFU/g) during the storage. The results indicate that the low fat buffalo milk yogurt is a good vehicle for developing symbiotic yogurt.Key words: Buffalo milk, symbiotic yogurt, refrigerated storage, probiotic survivability, physicochemical properties

Power-law distribution and scale-invariant structure from the first CHIME/FRB Fast Radio Burst catalog

We study the statistical property of fast radio bursts (FRBs) based on a selected sample of 190 one-off FRBs in the first CHIME/FRB catalog. Three power law models are used in the analysis, and we find the cumulative distribution functions of energy can be well fitted by bent power law and thresholded power law models. And the distribution functions of fluctuations of energy well follow the Tsallis $q$-Gaussian distribution. The $q$ values in the Tsallis $q$-Gaussian distribution are constant with small fluctuations for different temporal scale intervals, indicating a scale-invariant structure of the bursts. The earthquakes and soft gamma repeaters show similar properties, which are consistent with the predictions of self-organized criticality systems.Comment: 7 pages, 3 figures, 2 tables; accepted for publication in Research in Astronomy and Astrophysic