Metal nanogratings as one of the promising architectures for effective light trapping in organic photovoltaics (OPVs) have been actively studied over the past decade. Here we designed a novel metal nanowall grating wi...
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With the development of information technology, the increase of system information brings new problems to the military system effectiveness evaluation. Aiming at nonlinear, high dimension and strong coupling data of s...
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With the development of information technology, the increase of system information brings new problems to the military system effectiveness evaluation. Aiming at nonlinear, high dimension and strong coupling data of system effectiveness analysis, a data yard based system effectiveness evaluation and decision support method was proposed. Data recovery, subtraction, refinement and reconstruction operations were applied to the simulation data processing, then a data yard cube was built up to meet the multiple demands for system analysis of different levels and data dependency were reduced. Taking task-oriented networked fire controlsystem for example, its system effectiveness evaluation, timeliness evaluation and indices analysis were carried out, and practicability and validity of the method were verified in three levels. Applying data mining technology to the simulation system effectiveness evaluation decision-making, makes it get more extensive application.
Terrain perception in complex environment is important for Autonomous Land Vehicle to drive *** order to access the terrain information,in this paper,we present a terrain perception method based on Hidden Markov Model...
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Terrain perception in complex environment is important for Autonomous Land Vehicle to drive *** order to access the terrain information,in this paper,we present a terrain perception method based on Hidden Markov Model(HMM) which combines LIDAR with machine *** the basis of spatial fan-shaped model,terrain feature extraction is performed to acquire the observation *** markov models describe the vertical structure of the driving space and Viterbi algorithm is used for terrain *** the navigation decision is given based on the perception of the complex *** results show that the method can give an accurate environment description for ALV.
Image matching is widely used in machine vision, computer technology, industry and agriculture and other fields. Matching the characteristics of traditional methods such as SIFT has advantages of compressed informatio...
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ISBN:
(纸本)9781479970063
Image matching is widely used in machine vision, computer technology, industry and agriculture and other fields. Matching the characteristics of traditional methods such as SIFT has advantages of compressed information quantity, high precision, but there are also some deficiencies such as the large of calculation, long time, the object to be measured of position should be required accurately and etc. This paper presents image matching method based on improved SURF feature, and the analysis and comparison are made for the three kinds of image matching methods. The experiment proved: Sometimes it can also be A single SIFT or SURF, The improved SURF more can meet the requirements of parameter estimation accuracy and real-time. It can carry out accurate judgment, recognition for the digital image. It has certain theoretical value and practical value.
An operation strategy of the electric vehicle (EV) battery charging and swapping station is proposed in the paper. The strategy is established based on comprehensively consideration of the EV charging behaviors and ...
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An operation strategy of the electric vehicle (EV) battery charging and swapping station is proposed in the paper. The strategy is established based on comprehensively consideration of the EV charging behaviors and the possible mutual actions between battery charging and swapping. Three energy management strategies can be used in the station: charging period shifting, energy exchange between EVs, and energy supporting from surplus swapping batteries. Then an optimization model which minimizes the total energy management costs of the station is built. The Monte Carlo simulation is applied to analyze the characteristics of the EV battery charging load, and a heuristic algorithm is used to solve the strategy providing the relevant information of EVs and the battery charging and swapping station. The operation strategy can efficiently reduce battery charging during the high electricity price periods and make more reasonable use of the resources. Simulations prove the feasibility and rationality of the strategy.
Currently, most researches use signals, such as the coil current or voltage of solenoid, to identify parameters; typically, parameter identification method based on variation rate of coil current is applied for positi...
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Currently, most researches use signals, such as the coil current or voltage of solenoid, to identify parameters; typically, parameter identification method based on variation rate of coil current is applied for position estimation. The problem exists in these researches that the detected signals are prone to interference and difficult to obtain. This paper proposes a new method for detecting the core position by using flux characteristic quantity, which adds a new group of secondary winding to the coil of the ordinary switching electromagnet. On the basis of electromagnetic coupling theory analysis and simulation research of the magnetic field regarding the primary and secondary winding coils, and in accordance with the fact that under PWM control mode varying core position and operating current of windings produce different characteristic of flux increment of the secondary winding. The flux increment of the electromagnet winding can be obtained by conducting time domain integration for the induced voltage signal of the extracted secondary winding, and the core position from the two-dimensional fitting curve of the operating winding current and flux-linkage characteristic quantity of solenoid are calculated. The detecting and testing system of solenoid core position is developed based on the theoretical research. The testing results show that the flux characteristic quantity of switching electromagnet magnetic circuit is able to effectively show the core position and thus to accomplish the non-displacement transducer detection of the said core position of the switching electromagnet. This paper proposes a new method for detecting the core position by using flux characteristic quantity, which provides a new theory and method for switch solenoid to control the proportional valve.
For humanoid robots, there exist a class of challenging tasks, e.g. playing table tennis, which are non-repeatedly, triggered randomly by sensor events, and compelling the robots to produce reactive operations in very...
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For humanoid robots, there exist a class of challenging tasks, e.g. playing table tennis, which are non-repeatedly, triggered randomly by sensor events, and compelling the robots to produce reactive operations in very short time. Additionally, some key poses of the robot are partially constrained to accomplish the operations, and are usually adjusted during the operation execution. In this paper, efforts are made to generate trajectory for these operations. Firstly, an extended manipulability index is proposed to optimize the key poses so that the humanoid robot has the manipulability considering joint limits at the key poses, which makes it convenient to adjust the trajectory. Secondly, a fast approach to generating the whole trajectory consisting of all the key poses and the strategies to realize the trajectory adjustment when specifications change are proposed. Finally, the ZMP (Zero Moment Point) displacement excited by the reactive operations is also given to decide whether the generated trajectory is feasible. The effectiveness of the method is demonstrated through simulations.
Moving object detection is usually used in gray image, and the color image should be converted to gray images to achieve detection. However, the color object can't be described by simple gray information completel...
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Moving object detection is usually used in gray image, and the color image should be converted to gray images to achieve detection. However, the color object can't be described by simple gray information completely. In order to achieve automatic color moving object detection, the method based on automatic color clustering is especially proposed. Because the difference between adjacent pixels in an image is very small, the initial cluster center can be moved in the maximum distance. The proposed method can reduce the number of iterations and quicken convergence speed, meanwhile determine the number of color cluster and the location of the color object automatically. The proposed algorithm is validated in the actual system, experimental results show that the proposed method can automatically achieve color clustering for color image, while detect color objects.
Based on the excellent mechanical structure of the wheel-foot multi-joint mobile robot, we have strictly deduced the direct and inverse kinematical formulas of the robot's legs. So the theoretical method and techn...
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Based on the excellent mechanical structure of the wheel-foot multi-joint mobile robot, we have strictly deduced the direct and inverse kinematical formulas of the robot's legs. So the theoretical method and technology of gaits control for the wheel-foot multi-joint mobile robot have been explored out. By precisely analyzing the obstacle performance and the workspace of the robot's feet, the constraints and efficiency of the robot have been illustrated clearly. After studying the features of various gaits, we also have designed four kinds of specific gaits for the wheel-foot multi-joint mobile robot, including the swing forward gait, the crab-lateral gait, the bent-knee forward gait and the wheel-turn gait, to verify the mobile ability and control effects of the robot. Then we research most fully on the control features, the attitudes of legs, the simulation effects and the fluctuation of the robot's body when walking with these four kinds of gaits, in order to fully understand the performance of the robot. The results of simulations and actual prototype tests have proved that the wheel-foot multi-joint mobile robot, with special mechanical structure and reasonable gaits planning, can move fast and steadily with versatile gaits in various complex terrains. The effectiveness of the theoretical exploration and the technical implementation has been fully proved in this paper.
Considering two disadvantages in traditional gravity matching aided inertial navigation system, low matching accuracy and error accumulation, we propose an improved gravity matching algorithm and aided method for iner...
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Considering two disadvantages in traditional gravity matching aided inertial navigation system, low matching accuracy and error accumulation, we propose an improved gravity matching algorithm and aided method for inertial navigation system. Instead of using the sequence sampling, the single point sampling is applied to improve the structure of proposed algorithm, enhancing the matching speed and efficiency. In the aided navigation system method, we use combination of Sage-Husa adaptive filter and strong-tracked Kalman filter to make further optimal estimation of the matching trajectory. Simulation results show the effectiveness of the real-time ICCP algorithm and the combined filter algorithm. Comparing to the traditional methods, proposed method provides higher matching and navigation accuracy.
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