Efficient Model-Based Object Pose Estimation Based on Multi-Template Tracking and PnP Algorithms

[[abstract]]Three-Dimensional (3D) object pose estimation plays a crucial role in computer vision because it is an essential function in many practical applications. In this paper, we propose a real-time model-based object pose estimation algorithm, which integrates template matching and Perspective-n-Point (PnP) pose estimation methods to deal with this issue efficiently. The proposed method firstly extracts and matches keypoints of the scene image and the object reference image. Based on the matched keypoints, a two-dimensional (2D) planar transformation between the reference image and the detected object can be formulated by a homography matrix, which can initialize a template tracking algorithm efficiently. Based on the template tracking result, the correspondence between image features and control points of the Computer-Aided Design (CAD) model of the object can be determined efficiently, thus leading to a fast 3D pose tracking result. Finally, the 3D pose of the object with respect to the camera is estimated by a PnP solver based on the tracked 2D-3D correspondences, which improves the accuracy of the pose estimation. Experimental results show that the proposed method not only achieves real-time performance in tracking multiple objects, but also provides accurate pose estimation results. These advantages make the proposed method suitable for many practical applications, such as augmented reality.[[notice]]補正完

Exploring the Effects of EEG-Based Alpha Neurofeedback on Working Memory Capacity in Healthy Participants

Neurofeedback, an operant conditioning neuromodulation technique, uses information from brain activities in real-time via brain–computer interface (BCI) technology. This technique has been utilized to enhance the cognitive abilities, including working memory performance, of human beings. The aims of this study are to investigate how alpha neurofeedback can improve working memory performance in healthy participants and to explore the underlying neural mechanisms in a working memory task before and after neurofeedback. Thirty-six participants divided into the NFT group and the control group participated in this study. This study was not blinded, and both the participants and the researcher were aware of their group assignments. Increasing power in the alpha EEG band was used as a neurofeedback in the eyes-open condition only in the NFT group. The data were collected before and after neurofeedback while they were performing the N-back memory task (N = 1 and N = 2). Both groups showed improvement in their working memory performance. There was an enhancement in the power of their frontal alpha and beta activities with increased working memory load (i.e., 2-back). The experimental group showed improvements in their functional connections between different brain regions at the theta level. This effect was absent in the control group. Furthermore, brain hemispheric lateralization was found during the N-back task, and there were more intra-hemisphere connections than inter-hemisphere connections of the brain. These results suggest that healthy participants can benefit from neurofeedback and from having their brain networks changed after the training

Charged probes: turn-on selective fluorescence for RNA

RNA controls many biological processes. The selective detection and imaging of RNA molecules can provide information about their location, kinetics, and functions at the cellular level. The imidazolium-based positively charged probes would play a significant role in the deep investigation of RNA biomolecules to check their therapeutic potential and provide aids in the future rational molecular and drug design

Design and Analysis of 15 nm MOSFETs

We present the design and analysis of 15 nm NMOS transistors, fabricated on three different substrate materials -- namely silicon, indium nitride and indium arsenide. Close inspection on the I-V characteristic curves reveals that the saturation voltage and current of the indium arsenide transistors are significantly higher than the other two counterparts. We attribute this result to the high mobility of carriers in indium arsenide substrate. It is also observed that the breakdown voltages of the indium arsenide transistors are also one of the highest. The breakdown behaviour shows that transistors fabricated on indium arsenide substrate renders reasonably high robustness. Due to high channel length modulation effect, it could also be seen that current variation between saturation and breakdown currents is the highest in the conventional silicon transistors. Our analysis suggests that indium arsenide could be an alternative substrate material in the design and fabrication of nano-scale MOSFETs. For devices which may require high power consumption (and therefore high current and voltage), indium arsenide can also be considered as an appropriate substrate material

Analysis of Hammerhead Probes in a Rectangular Waveguide

We present the analysis of hammerhead probes with different geometrical sizes in a rectangular waveguide. In order to investigate coupling efficiency, we vary the widths and thicknesses of the head and its handle. The results show that the probe gives higher return loss when the widths of the structure are relatively smaller, i.e. the head is of the same size and the handle is smaller than the core of the coaxial cable. Experimental measurements show that the impedance of the probe increases in corresponds to the width of the head. The poor performance found in the probe with a larger size can therefore be attributed to the impedance mismatch between the probe and the cable. It can also be observed that the probe with a thicker head and thinner handle exhibits the highest return loss and largest bandwidth. Indeed, by carefully adjusting the geometry of the hammerhead probe, the coupling efficiency is found to be better than conventional rectangular microstrip and coaxial probes. The thick head hammerhead probe gives about 22.72 dB and 31.36 dB higher peak return loss than those of the rectangular microstrip and coaxial probes. Although the bandwidths of the thick head hammerhead probe and the rectangular microstrip probe are similar, i.e. approximately 22.18 GHz, its bandwidth is about 5.88 GHz wider than the conventional coaxial probe

Mathematical Analysis of Mixed Convective Peristaltic Flow for Chemically Reactive Casson Nanofluid

Nanofluids are extremely beneficial to scientists because of their excellent heat transfer rates, which have numerous medical and industrial applications. The current study deals with the peristaltic flow of nanofluid (i.e., Casson nanofluid) in a symmetric elastic/compliant channel. Buongiorno’s framework of nanofluids was utilized to create the equations for flow and thermal/mass transfer along with the features of Brownian motion and thermophoresis. Slip conditions were applied to the compliant channel walls. The thermal field incorporated the attributes of viscous dissipation, ohmic heating, and thermal radiation. First-order chemical-reaction impacts were inserted in the mass transport. The influences of the Hall current and mixed convection were also presented within the momentum equations. Lubricant approximations were exploited to make the system of equations more simplified for the proposed framework. The solution of a nonlinear system of ODEs was accomplished via a numerical method. The influence of pertinent variables was examined by constructing graphs of fluid velocity, temperature profile, and rate of heat transfer. The concentration field was scrutinized via table. The velocity of the fluid declined with the increment of the Hartman number. The effects of thermal radiation and thermal Grashof number on temperature showed opposite behavior. Heat transfer rate was improved by raising the Casson fluid parameter and the Brownian motion parameter