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We report the observation of the torsional vibration of an optically levitated nanodiamond in vacuum. We propose a scheme to achieve torsional ground state cooling, and utilize the electron spin-torsional coupling to do quantum simulation.
Traditional PLC system in the event of system failure, there is no perfect mechanism to ensure the safety of control, the safety PLC based on heterogeneous dual-processor redundant structure can meet the requirements of industrial control for equipment and personnel, improve the reliability of industrial control. In this paper, according to the operation requirements of safety PLC based on heterogeneous...
The unmanned multi-ducted-fan flying vehicle is a kind of novel multi-purpose platform for future transportation. In this paper, flight dynamics model is established based on aerodynamics principles and rigid body dynamics theory. To make the controller of the multi-ducted fan flying vehicle more robust, a double closed loop PID controller is put forward with non-smooth parameters optimization method...
Due to the low weight of monocular camera, monocular Simultaneous Localization and Mapping (SLAM) is an area of popular research and promotes countless applications of micro Unmanned Aerial Vehicles (UAVs), especially in some GPS-denied indoor environments. Nevertheless, the motion of UAVs is often faster and more complex than that of ground-based robots. It would also lead to error accumulation if...
Online quality inspection is an effective way to guarantee the quality of PET bottles packaging on the high-speed filling production line. This paper focused on studying and developing a machine vision inspecting system for on-line defects detection of PET caps without support rings. An image processing algorithm was proposed to detecting the serious defects such as surface foreign matters and link...
In this paper, we design a novel knee exoskeleton. The designed exoskeleton has a 1 DOF with knee joint actuated in the sagittal plane. The exoskeleton is actuated base on Series Elastic Actuator (SEA) instead of traditonal stiff actuator. SEA is a compliant actuator, having the advantages of low output impedance, low friction, high quality force control and backdrivability. Thanks to these nice characteristics,...
Multi-class classification algorithm of support vector machine (SVM) has always been a research hotspot. A new multi-class SVM algorithm, naming recall reordering adaptive directed acyclic graphs (RRADAG), is proposed from the perspective of error detection to solve the error accumulation existed in multi-class SVM algorithm of which is based on Directed Acyclic Graphs (DAG). By detecting the output...
To satisfy the enormous data transmission demands, caching popular files into memories at user terminals (UTs) is a promising solution, which can alleviate the heavy burden on backhaul links and shorten the transmission delay. In this paper, we study the user caching strategy by exploiting the effect of user mobility. The contact of mobile users is modeled as the Poisson process. Both Zipf distributed...
Prototyping and proper testing of the electrical control unit of more electric aircraft (MEA) under various load profiles and fault conditions is necessary to ensure the performance of the controller. In order to solve the problems such as complicated operation, high experiment cost and long development period in aircraft power system traditional test method, this paper presents a semi-physical real-time...
Recommender systems represent an important research area with a variety of applications. Review topic based recommendation aims at inferring users ratings over their unrated items using existing reviews and corresponding ratings. Though combining latent factors and review topics shows the strength in improving the effectiveness and interpretability for rating prediction, it brings uncertainties led...
A method for mitigating antenna motion effects in high frequency radar Doppler spectra developed from ocean backscatter is proposed. Based on the established radar cross section models for a fixed antenna and for an antenna on a floating platform, the relationship between these models is developed. Through this relationship, motion compensation can be achieved by deconvolving the radar cross section...
A real-time vision-based object tracking system embedded in a quadrotor is presented in this paper. The integrated system is expected to enable the quadrotor to track a target object and keep with a fixed distance. A robust object tracking method via improving Kernelized Correlation Filters algorithm is proposed to achieve accurate visual tracking. In addition, a PID controller is applied to utilize...
With technology scaling, process variations influence the performance, power and reliability significantly, especially for multi-core and many-core systems. Faulty-tolerant multi-core architectures are paid widely attention to, which integrate redundant cores to improve the manufacturing yield. In this paper, a two-stage variation-aware task mapping scheme is proposed for multi-core NoCs with redundant...
Delay-tolerant networks (DTNs) are wireless mobile networks that exhibit frequent intermittent connectivity and large transmission delay among nodes. Research results have shown that quota-controlled routing protocols can strike a reasonable balance between routing performance and cost, where quota is a value to control the number of message copies. However, the question of how to set the optimal...
Heterogeneous MPSoCs consisting of cores with different performance/power behaviors are widely used in many power-constrained real-time systems. Both soft-error reliability and lifetime reliability are key concerns in such systems. Although existing work have investigated related problems, they either focus on one of the two reliability concerns or propose complicated scheduling algorithms that cannot...
Measuring inconsistency degrees of inconsistent knowledge bases is an important problem as it provides context information for facilitating inconsistency handling. Many methods have been proposed to solve this problem and a main class of them is based on some kind of paraconsistent semantics. In this paper, we consider the computational aspects of inconsistency degrees of propositional knowledge bases...
This paper presents an online nonlinear actuator fault detection and isolation system, aiming at monitoring monitor the health of a novel ducted fan UAV. In order to cover wider flight envelope, an unscented multiple model adaptive estimation method is introduced as an extension of the EKF-based method. The proposed method provides a bank of UKFs running in parallel, each of which is responsible for...
Traditional pneumatic servo systems usually use load ports linkage control, but it doesn't always work well. When the gravitational load in the systems is large, conventional pneumatic servo systems can not meet the needs of high positioning accuracy. This study takes the method of independent load ports control technology. The method presented in this paper has one modification. It controls two chambers...
This paper addresses the problem of relay selection and power allocation in a device-to-device (D2D) communication underlaying heterogeneous cellular network. For the femto user equipments (FUEs) relay selection, two novel relay selection metrics are derived, which take both the intra-tier and cross-tier interferences into account. Based on the proposed metrics, centralized and distributed methods...
The first-order high frequency radar cross section of the ocean surface is derived for an antenna on a floating platform. In this analysis, simulations are conducted for more complicated platform motion than appear in earlier work and comparisons are made to model outputs for a fixed antenna. Results show that motion-induced peaks appear symmetrically in the Doppler frequency. The magnitude and width...
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