In recent years, unmanned autonomous vehicle navigation technology or UAV research is a hot topic in the field of machine vision, and obstacle detection is the basis of autonomous navigation. In this thesis, the autho...
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ISBN:
(纸本)9781479953905
In recent years, unmanned autonomous vehicle navigation technology or UAV research is a hot topic in the field of machine vision, and obstacle detection is the basis of autonomous navigation. In this thesis, the author analyzed the deficiency of stereoscopic vision and classified current monocular obstacle detection algorithms. According to the properties of algorithms, this paper elaborated the function of algorithms based on features, focal length and movements respectively. The author also discussed current situation and prospects for various types of algorithms, including feature extraction and matching, focusing and defocusing model, background subtraction, frame difference and optical flow. Finally, this paper summarized advantages and disadvantages of different autonomous navigation algorithm and discussed the prospect of the monocular obstacle detection technology.
The algorithm presented here is used on unmanned aerial vehicles system. In 2013,*** proposed a matching cost computation model(or function), This matching cost model combined three kinds of constraints, the cost func...
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ISBN:
(纸本)9781479953905
The algorithm presented here is used on unmanned aerial vehicles system. In 2013,*** proposed a matching cost computation model(or function), This matching cost model combined three kinds of constraints, the cost function is formulated by combining three individual costs: a cost computed on an extended census transformation of the images;the absolute difference cost, taking into account information from colour channels;and a cost based on the principal image derivatives. Experiments show that the cost function is excellent performance in similar estimates. Apply it to the stereo matching of ancient buildings, it is favorable for practical. However, this experiment, in color mutated region, leaded to blurred border. Therefore, our proposed method added color space structural information, which based on HVS Weber's law, to the cost function. we use the differential excitation of WLD reflects the structure of color space. This robust cost measures can reduce percent of bad pixels in mutated color region. The proposed method use color image, which is used after epipolar line rectification.
Hausdorff distance measure is one of the widely adopted feature-based image matching algo- rithms due to its simplicity and accuracy. However, it is considered that its robustness still needs to be improved. In this p...
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Hausdorff distance measure is one of the widely adopted feature-based image matching algo- rithms due to its simplicity and accuracy. However, it is considered that its robustness still needs to be improved. In this paper, various forms of original and improved Hausdorff distance （HD） and their limitations are studied. Focusing on robust Hausdorff distance （ RHD）, an improved RHD with an adaptive outlier point threshold selection method is proposed. Furthermore, another new form of the Hausdorff distance which possesses the merits of RHD and M-HD is prsented. Finally, a recur- sire algorithm is introduced to accelerate the image matching speed of Hausdorff algorithms. Exten- sive simulation and experiment results are presented to validate the feasibility of the proposed Haus- dorff distance algorithm.
Novel graphite sheet (GTS) has been used as anodic catalyst in microbial fuel cell (MFC) base on Escherichia coli (ATCC 25922) and characterized by cyclic voltammogram (CV) and polarization curve. Findings from these ...
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Novel graphite sheet (GTS) has been used as anodic catalyst in microbial fuel cell (MFC) base on Escherichia coli (ATCC 25922) and characterized by cyclic voltammogram (CV) and polarization curve. Findings from these measurements revealed that GTS showed an excellent electrochemical performance. The two-chambered MFC operated with the GTS anode delivered a maximum power density of 2249 mW/m(2). Scanning electron microscopy (SEM) results indicate that the high power output could be attributed to the high biocompatibility of the GTS. These results demonstrate that the GTS is promising in the application of microbial fuel cells. (C) 2013 Elsevier B.V. All rights reserved.
A new type high-g(10000g) three-dimension silicon piezoresistive accelerometer is introduced in this paper. The sensor's principle, structure, mechanical analysis and measurement circuit are described. Finally, fa...
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ISBN:
(纸本)7800034410
A new type high-g(10000g) three-dimension silicon piezoresistive accelerometer is introduced in this paper. The sensor's principle, structure, mechanical analysis and measurement circuit are described. Finally, fabrication result (SEM photo of the accelerometer) is publicized.
In this paper, a graphene-based magnetic nano-composite (Fe3O4@G) was synthesized by covalent bonding. The presence of Fe3O4 was characterized by fourier transform infrared spectroscopy, X-ray diffraction, thermo-grav...
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In this paper, a graphene-based magnetic nano-composite (Fe3O4@G) was synthesized by covalent bonding. The presence of Fe3O4 was characterized by fourier transform infrared spectroscopy, X-ray diffraction, thermo-gravimetric analysis, scanning electron microscopy (SEM), and transmission electron microscopy. Subsequently, the Fe3O4@G was used as adsorbent for the extraction of eight organochlorine pesticides in orange juice samples prior to their gas chromatography mass spectrometry detection. Various experimental parameters affecting the extraction efficiencies, such as the amount of Fe3O4@G, extraction time, the pH of the sample solution and desorption conditions were investigated. Under optimized experimental conditions, good linearity existed in the range of 1.0-200.0 ng mL(-1) for all the analytes with the correlation coefficients (R-2) ranging from 0.9904 to 0.9992. The limits of detection (S/N = 3) of the method for the compounds were between 0.01 and 0.05 ng mL(-1). Good reproducibilities were obtained with the relative standard deviations (RSDs) below 9.6 %. The recoveries of the method were in the range between 73.8 and 105.4 % with RSDs less than 7.7 %.
This paper proposes a new self-tuning Kalman filter with good tracking ability for unknown noise statistics and unknown abrupt input change. The new filter can easily compute unknown abrupt input and steady-state gain...
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Due to periodic occlusion caused by rotating vehicles, the antenna cannot continuously receive GNSS signal. At the same time, the Doppler frequency shift caused by rotation also brings additional influence on GNSS sig...
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Two new baccharane-type glycosides（1 and 2）, together with seven known baccharane-type glycosides （3u9） hosenkoside A, hosenkoside B, hosenkoside C, hosenkoside F, hosenkoside M, hosenkoside K and hosenko- side G ...
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Two new baccharane-type glycosides（1 and 2）, together with seven known baccharane-type glycosides （3u9） hosenkoside A, hosenkoside B, hosenkoside C, hosenkoside F, hosenkoside M, hosenkoside K and hosenko- side G were isolated from the dried seeds of Impatientis balsamina L. The new baccharane-type glycosides were identified as honsenkol A-3-O-β-D-glucopyranosyl-26-O-p-D-glucopyranosyl-28-O-β-D-glucopyranosyl-O-β-D- glucopyranosyl（1） and （3S,4R,17R,20S）17-hydrroxy-3-O-β-D-xylopyranose（12）-β-D-glucopyranosyl-26-O-β-D- glucopyranosyl-28-O-β-D-glucopyranosyl-21,24-epoxybaccharane（2）, respectively, by spectroscopic methods, in- cluding NMR（1D and 2D）, IR and HR-ESI-MS. Compounds 1 and 2 were evaluated for in vitro inhibitory activity against the cell lines. Compound 2 with a new baccharane skeleton had anti-hepatic fibrosis activity against A375 cells in bioassay results, which means the new compounds have potential value in antitumor applications.
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