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To cultivate professional sports referees, we develop a sports referee training system, which can recognize whether a trainee wearing the Myo armband makes correct judging signals while watching a prerecorded professional game. The system has to correctly recognize a set of gestures related to official referee's signals (ORSs) and another set of gestures used to intuitively interact with the system. These two gesture sets involve both large motion and subtle motion gestures, and the existing sensor-based methods using handcrafted features do not work well on recognizing all kinds of these gestures. In this work, deep belief networks (DBNs) are utilized to learn more representative features for hand gesture recognition, and selective handcrafted features are combined with the DBN features to achieve more robust recognition results. Moreover, a hierarchical recognition scheme is designed to first recognize the input gesture as a large or subtle motion gesture, and the corresponding classifiers for large motion gestures and subtle motion gestures are further used to obtain the final recognition result. Moreover, the Myo armband consists of eight-channel surface electromyography (sEMG) sensors and an inertial measurement unit (IMU), and these heterogeneous signals can be fused to achieve better recognition accuracy. We take basketball as an example to validate the proposed training system, and the experimental results show that the proposed hierarchical scheme considering DBN features of multimodality data outperforms other methods.

This paper aims to characterize the photoelectrochemical properties of the visible-light enabling titanium dioxide (TiO2) film electrodes prepared by codoping nitrogen (N) and a presputtered carbon film (C-film) onto indium tin oxide (ITO) glass substrates using a direct current (DC) magnetron sputtering technique. To improve its photoelectrochemical properties, different amount of C-doping sources, 2 h and 4 h C-film, are chose to prepare the N/C-codoped TiO2 film electrodes. Under visible-light (420 < lambda < 610 nm) illumination, a remarkable photocurrent density of 22 microA/cm2 is obtained for the N/C-TiO2 film electrode prepared with a 4 h C-film (NC(4)-T) at an applied potential of +1.2 V versus SCE. Under ultraviolet (lambda approximately 365 nm) illumination, the NC(4)-T film electrode also exhibits the highest photocurrent density of 0.23 mA/cm2 among all samples tested. A more negative flat band potential of NC(4)-T film electrode is attributed to the synergistic effect of N/C codoping. The XRD spectrum of the NC(4)-T film electrode shows mainly the well-crystallized anatase TiO2 phase and an extremely intense (211) plane. Thus, photoelectrochemical activity of the NC(4)-T film electrode can be ascribed to the well-crystallized columnar crystals with pores at its grain boundary, open surface morphology, which are revealed by SEM and TEM images, and a more negative flat band potential. The visible-light induced activity is mostly enhanced as a result of the synergistic effects of N/C-codoping into the TiO2 crystals. A potential application to photocatalytic splitting of water for hydrogen evolution using solar light is practically possible.

Visible-light-responsive layered titanium dioxide/tin indium oxide (TiO2/ITO) catalysts prepared on unheated glass slides by DC magnetron sputtering were investigated in this study. Transmittance spectra of the catalyst revealed that an interference pattern gradually appeared at wavelengths of 550-650 nm which indicated a strong light absorption up to this region. The red-shift may be ascribed to the difference in both compositions and phase structures of the layered catalyst. X-ray diffraction (XRD) and scanning electron microscopy (SEM) exhibited a strong columnar growth morphology with highly faceted grains and a distinct (211) texture. Selected area electron diffraction (SAED) measurements also confirmed the crystalline nature of the layered catalyst. The SIMS elemental depth profiles showed that tin atoms permeated into the overlaid TiO2 film. This could be resulted from the diffusion of tin from the intercalated ITO thin film during the TiO2 deposition. It suggested that the tin atoms played an important role on the microstructure formation and on the catalytic property of the layered catalyst. This was also confirmed by the cross-sectional TEM images where a layer of crystalline anatase TiO2 grown epitaxially above the intercalated ITO thin film was observed. In addition, a better crystalline TiO2 film with larger grains of 120-180 nm and a higher specific surface area of 1.55 was obtained on successively coated ITO substrate. The layered catalysts showed significant photocatalytic activity on methylene blue (MB) degradation illuminated by ultra-violet (UV 365 nm) and visible light (420 < lambda < 620 nm) sources. A preliminary study on water splitting for hydrogen production showed that a noticeable amount of hydrogen was generated at Pt cathode by employing electrical potential (approximately 0.5 V) and UV-light and visible (lambda > 420 nm) sources via a TiO2/ITO anode.

Binary optimization is a widely investigated topic in integer linear programming. This study proposes a DNA-based computing algorithm for solving the significantly large binary integer programming (BIP) problem. The proposed approach is based upon Adleman and Lipton's DNA operations to solve the BIP problem. The potential of DNA computation for the BIP problem is promising given the operational time complexity of O(nxk).