This paper examines the advantages and disadvantages of noninvasive and remote temperature estimation employing magnetic nanoparticles (MNPs) in DC and AC applied fields. A Langevin function that describes the magneti...
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This paper examines the advantages and disadvantages of noninvasive and remote temperature estimation employing magnetic nanoparticles (MNPs) in DC and AC applied fields. A Langevin function that describes the magnetization of the MNPs in different applied magnetic fields is investigated to obtain a noninvasive and remote measurement of on-site temperature using MNPs. Several nonlinear functions, in which temperature and concentration are independent variances, are found by discretizing the Langevin function model of the magnetization of MNPs. Then, the temperature estimation range from 310 K to 350 K is transformed to the solution of the nonlinear function using the temperature independence of the saturation magnetization of the MNPs.
Multi micro parts recognition is one of the important tasks for the assembly of multi micro objects in micromanipulation. Zernike moments have been widely used as invariant features in many image analysis and pattern ...
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Character information is hard to detect in billet scene images by CCD camera. In this paper, we present a method for detection of billet characters from measurements of recursive segmented image. This recursive segmen...
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Character information is hard to detect in billet scene images by CCD camera. In this paper, we present a method for detection of billet characters from measurements of recursive segmented image. This recursive segmented method can be used in a wide variety of billet scenes. According to high temperature and complex scene in the rolling line, we use an effective clustering and projection characteristics to determine the terminal condition of recursive segmentation. Then we can label character candidate regions in turn by this effective characteristics, and select the regions we want to achieve. The experiments show that this method makes full use of the characteristics of region and clustering. It can improve the quality of detection, and the detection result meets the need of practical application.
The focus of this paper is the design and development of an automatic system for microassembly. The automatic processing is made possible by (i) the development of a machine vision algorithm to identify the targets an...
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The focus of this paper is the design and development of an automatic system for microassembly. The automatic processing is made possible by (i) the development of a machine vision algorithm to identify the targets and end-effectors, (ii) an uncalibrated visual servoing algorithm to lead the end-effector to grasp the micro-pieces and then assemble the target. The experimental results demonstrate that this prototype microassembly system is effective and practicable for automatic microassembly applications.
The license plate location technique is an important imageprocessing step in license plate recognition system. Vehicle license plates are distinguished from backgrounds using features proposed in existing literatures...
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The license plate location technique is an important imageprocessing step in license plate recognition system. Vehicle license plates are distinguished from backgrounds using features proposed in existing literatures. However, the effect of location is quite affected by feature selection. In this paper, we propose a method of precise license plate location fusing salient features. The method is mainly divided into three steps. First, candidate license plate regions are detected using improved Harris corner feature with much less time than traditional method. Then, candidates are sifted to only retain license plates based on two salient features named color combination and mean difference which are first proposed in this paper. Finally, the license plates are located precisely according to the projection feature. In experiment, the proposed algorithm was tested with 1942 real images captured in different environment and the license plates are successfully located as 97.6% in average with only 109ms. The experiment results demonstrates the effectiveness and efficient of our algorithm.
A time-based nested partition (NP) approach is proposed to solve resource-constrained project scheduling problem (RCPSP) in this paper. In iteration, one activity is selected as the base point of which the finish ...
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A time-based nested partition (NP) approach is proposed to solve resource-constrained project scheduling problem (RCPSP) in this paper. In iteration, one activity is selected as the base point of which the finish time interval calculated by CPM is divided into two parts to form two subregions on the basis of the promising region of the last iteration. Then sampling is taken in both subregions and the surrounding region to determine the promising region and aggregate the other as the surrounding region of this iteration so that whether the backtracking or the moving operation being performed is determined. Double justification is also performed in iteration to improve the results. The results of numerical tests on PSPLIB show the effectiveness and time-efficient of the proposed NP method.
Presently pneumatic muscles (PMs) are used in various applications due to their simple construction, lightweight and high force to weight ***, pneumatic muscles are facing various problems due to their nonlinear chara...
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Presently pneumatic muscles (PMs) are used in various applications due to their simple construction, lightweight and high force to weight ***, pneumatic muscles are facing various problems due to their nonlinear characteristic in various mechanical *** model of PM is nonlinear and *** this paper, a Lyapunov-based control (LBC) approach is proposed for the control of *** on the nonlinear characteristic of PM, a dynamic model of the PM actuator with pulling a mass against gravity is *** objectives are both a regulation and an asymptotic tracking of a desired *** analysis based on Lyapunov method with respect to our proposed control law is *** simulation results show the validity, effectiveness and enhancing robustness of the proposed method.
This paper presents an active disturbance rejection guidance method using quadratic transition for the atmospheric ascent guidance problem. The quadratic transition is designed from the current flight states with a re...
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This paper presents an active disturbance rejection guidance method using quadratic transition for the atmospheric ascent guidance problem. The quadratic transition is designed from the current flight states with a reference trajectory planned off-board. For any states error, the solution of the designed quadratic transition converges to the reference trajectory. The guidance command is obtained from the derivative of the designed quadratic transition. For the unknown modeling error, the guidance command is compensated using the estimated disturbances from the extended state observer. Computer simulation for GHV (Generic Hypersonic Air Vehicle) model, which includes initial states error and modeling error, shows great accuracy and effectiveness of this guidance method.
Landing footprint of an entry vehicle provides critical information for mission planning. Conventional methods calculate it through solving a family of multi-constraints optimal control problems. It is difficult to so...
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Landing footprint of an entry vehicle provides critical information for mission planning. Conventional methods calculate it through solving a family of multi-constraints optimal control problems. It is difficult to solve. To generate the boundary of it, we proposed a new scheme based on differential evolution(DE). Utilizing DE's parallelism, each run generates one side instead of one point of the boundary. To get the full boundary, just need run the algorithm two times. The algorithm's merits include accurate, fast, not relying on simplification of the system, all control variables are under consideration and facilitating parallel programming.
It is difficult to guide the entry vehicle to prescribed area due to the disperse of environment and kinematics. Through predicted residual range at the current state based on drag acceleration, we developed a predict...
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It is difficult to guide the entry vehicle to prescribed area due to the disperse of environment and kinematics. Through predicted residual range at the current state based on drag acceleration, we developed a predictor-corrector guidance law which doesn't need iteration to figure out the reference trajectory. Then using extended state observer based controller to track the reference trajectory. We use several missions(under various disperse conditions) to test the guidance law. Simulation results demonstrated that the guidance law is able to achieve the prescribed terminal conditions under various perturbations in the aerodynamic coefficients, the density of the atmosphere and the mass of the vehicle.
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