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Spherical cameras are widely used for robot perception because of their full 360 degree fields of view. However, the robot body is always seen in the view, causing occlusions. In this paper, we propose a video completion method which is able to remove occlusions fast and recover the occluded background accurately. We first estimate motion in a 2D dense spherical optical flow field. Then we interpolate...
This paper presents the multi-UAVs cooperative target observation and tracking considering the communication interference and the propagation loss. UAVs are assigned to the appropriate target group which maximises information defined by the Fisher information matrix (FIM). We propose multi-UAVs cooperative target optimal measurement and tracking models considering the communication factors. Using...
The turret system is one of the key functional components of the CNC lathe. Therefore it is important that the reliability of the turret system is optimised. In this paper, an imperfect preventive maintenance strategy, based on the Weibull distribution, for the turret system of the CNC lathe is proposed. The restoration and failure intensity increase factors are consistent with a uniform distribution...
After the random failure period, CNC machine tools will enter the wear-out failure period as a result of abrasion, fatigue and aging. Therefore, it is extremely important to monitor the changing trend of operation state and thus to construct rational maintenance policy or determine when to scrap it. In this paper, the mean time between failures (MTBF) is chosen to be the characteristic variable of...
In order to achieve the time domain load signals of CNC lathe during the cutting process, a new signal processing method based on improved Neighbor Block was proposed according to the character of noise in this paper. First, statistical variance smoothing method was utilized to remove the singular points. Then, denoising method of Neighbor Block was chosen. Finally, feasibility of wavelet basis was...
Aiming at the large bias of LSE (Least Squares Estimation) in estimating MTBF (mean time between failures) under a small sample of data, a Bayesian MTBF estimating method is proposed for NC (numerical control) machine tools. To solve difficulty in directly presenting the prior distributions of Weibull parameters, an expert-judgment method which incorporates prior information is developed to indirectly...
The purpose of this study is to develop a new system to synchronously control the simulated robot and humanoid robot based on the skeletal tracking technology. This system is a human-robot interaction system. Human can control the robot through the skeletal tracking technology without placing any marker on the subject's body. We use the Microsoft Kinect to get the skeleton framework information of...
From a point view of nonlinear dynamics, the electrical activity of the heart is a complex dynamical system, whose dynamics reflects the actual state of health of the heart. Nonlinear signal-processing methods are needed in order to accurately characterize these signals and improve understanding of cardiac arrhythmias. Recent developments on reconstructible signals and multiscale information content...
Cardiac arrhythmias are one of the most important death causes in the world. Compared to the numerical models, the experimental ones provide a more realistic tool to study the mechanisms of cardiac arrhythmias. The in vitro culture of cardiac cells developed on the Multi-Electrodes Array (MEA) constitutes a suitable model in this context. The extracellular field potential (EFP) acquired from the MEA...
A mixed reliability evaluation and prediction method which is particularly suitable for the machining center was proposed in this study, considering the poor adaptability of the current reliability evaluation and prediction method. Using fault occurrence time as modeling parameter and based on the empirical modeling technique, this method evaluates the realtime reliability of the machining center...
The cardiac electrical activity follows a complex dynamics whose accurate description is crucial to characterize arrhythmias and classify their complexity. Rhythm reflects the connection topology of pacemaker cells at their source. Hence, characterizing the attractors as nonlinear, effective dynamics can capture the key parameters without imposing any particular model on the empirical signals. A dynamic...
Nowadays, with the developing of the computer science, computer vision is widely used in many areas. It is still a major problem about feature recognition in complex background and uneven intensity of light environment. Some researchers have already achieved in particular conditions. With the robot stepping into family, it is necessary to conduct in-depth study about feature recognition and access...
The purpose of this study is to develop a potential method to quantify the effect of functional electrical stimulation (FES) on hemiplegic drop-foot (HDF) patients' movements. This method evaluates the effect of FES by comparing the ankle-angles of movements with and without FES. The change of the ankle-angles is one of the significant characteristics of the recovery of drop-foot. Therefore, this...
Multicode STBC-MIMO systems can provide flexibility in the diversity-multiplexing gain tradeoff. It is worth noting that multicode operation can provide additional degrees of freedom in the code domain to achieve high data rates. Meanwhile an immune-clonal-selection-based minimum-BER detection algorithm (ICS-MBER) is proposed for the multicode STBC-MIMO systems. The main idea is to directly minimize...
In the process of maintainability allocation of numerical control (NC) machine tools, many influence factors should be considered, and some of which are difficult to analyze quantitatively. In order to solve the above-mentioned problem, this paper proposed a new method for maintainability allocation, which comprehensively applied interval analysis, fuzzy comprehensive evaluation, and analytic hierarchy...
This paper proposed a urban design auxiliary support system using Geographic information technology on the understanding of urban design operation. In this paper, system function requirements are detailedly analyzed, and system design is given based on the analysis of system function requirements.
Failure mode analysis is important in CNC machine tool. In order to assess the failure mode of CNC machine tool, this paper described a new fuzzy FMEA model integrating with fuzzy linguistic scale method. The model proposed a risk-space diagram to explicit the relationship of S,O and D. On the basis of the risk-space diagram, risk priority number is calculated by weighted Euclidean Distance formula...
This study investigates the existence of the pseudo complex fractionated atrial electrogram (CFAE) at cellular level. Our assumptions are based on the fact that CFAEs are linked to the generation of the spiral waves. These are created using a numerical model and an experimental model of in vitro culture of neonatal rats cardiac cells. Pseudo bipolar electrograms resulting from these two models are...
Experiments in vitro on a Microelectrode Array (MEA) platform show that electrical stimulation can provoke the generation of spiral waves in cardiac tissue. Nevertheless, the conditions leading to this artificial fibrillation state remain unclear. In order to have a better understanding of this phenomenon, a numerical simulation study has been conducted. The results obtained with a two-dimensional...
Partial transmit sequences (PTS) is one of the most effective method for reducing the peak-to-average power ratio (PAPR) in OFDM systems. By carefully investigating the correlation among the candidate signals in PTS, a novel PTS method using optimized (or partially optimized) phase factors, denoted as PTS-OPV, is proposed. Specifically, the phase vectors are applied in weighting the subblocks and...
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