In order to speed up logistics distribution efficiency and reduce distribution costs, logistics companies around the world began to use drones for related distribution work. In addition to upgrading the hardware techn...
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In order to speed up logistics distribution efficiency and reduce distribution costs, logistics companies around the world began to use drones for related distribution work. In addition to upgrading the hardware technology of UAV, optimizing the distribution path is also one of the ways to reduce the distribution cost of UAV distribution center. In this paper, the location of UAV distribution center will be studied theoretically based on the economic optimization and equipment maintenance optimization. Finally, the feasibility of the algorithm is verified by simple simulation application.
Unbalanced amount of the accumulated charge on the anodic grid of a Photomultiplier Tube combined with center of gravity position reconstruction algorithms produces systematically shifts towards the center of the imag...
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ISBN:
(纸本)9781728141640
Unbalanced amount of the accumulated charge on the anodic grid of a Photomultiplier Tube combined with center of gravity position reconstruction algorithms produces systematically shifts towards the center of the image, reducing the effective Field of View and causing deformation effects at the edges of the image. The main purpose of this study is to detect the origin of this kind of image deformation, mainly known as barreloid distortion, and in addition to propose appropriate algorithmic approaches for the correction of these effects on planar imaging. Various analyses with simulated and real data are presented and the success of the method is discussed with different phantom geometries measured with a small field gamma-Camera system.
Quick and presumptive identification of seized drug samples without destroying evidence is necessary for law enforcement officials to control the trafficking and abuse of drugs. This work reports an automated screenin...
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Quick and presumptive identification of seized drug samples without destroying evidence is necessary for law enforcement officials to control the trafficking and abuse of drugs. This work reports an automated screening method to detect the presence of cocaine in seized samples using portable Fourier transform infrared (FT-IR) spectrometers. The method is based on the identification of well-defined characteristic vibrational frequencies related to the functional group of the cocaine molecule and is fully automated through the use of an expert system. Traditionally, analysts look for key functional group bands in the infrared spectra and characterization of the molecules present is dependent on user interpretation. This implies the need for user expertise, especially in samples that likely are mixtures. As such, this approach is biased and also not suitable for non-experts. The method proposed in this work uses the well-established center of gravity peak picking mathematical algorithm and combines it with the conditional reporting feature in MicroLab software to provide an automated method that can be successfully employed by users with varied experience levels. The method reports the confidence level of cocaine present only when a certain number of cocaine related peaks are identified by the automated method. Unlike library search and chemometric methods that are dependent on the library database or the training set samples used to build the calibration model, the proposed method is relatively independent of adulterants and diluents present in the seized mixture. This automated method in combination with a portable FT-IR spectrometer provides law enforcement officials, criminal investigators, or forensic experts a quick field-based prescreening capability for the presence of cocaine in seized drug samples.
This paper presents an extended version of the separation plane algorithm for subgradient-based finite-dimensional nondifferentiable convex optimization. The extension introduces additional cuts for epigraph of the co...
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ISBN:
(纸本)9783319449142;9783319449135
This paper presents an extended version of the separation plane algorithm for subgradient-based finite-dimensional nondifferentiable convex optimization. The extension introduces additional cuts for epigraph of the conjugate of objective function which improve the convergence of the algorithm. The case of affine cuts is considered in more details and it is shown that it requires solution of an auxiliary convex subproblem the dimensionality of which depends on the number of additional cuts and can be kept arbitrary low. Therefore algorithm can make use of the efficient algorithms of low-dimensional nondifferentiable convex optimization which overcome known computational complexity bounds for the general case.
In the isolation testing platform, vibration spectrum is tested, The course of test, result from atmospheric disturbances and optical aberration, That studies typical tracking facula center of gravity algorithm and su...
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ISBN:
(纸本)9781457703218
In the isolation testing platform, vibration spectrum is tested, The course of test, result from atmospheric disturbances and optical aberration, That studies typical tracking facula center of gravity algorithm and summarizes reason of the algorithm precision, Result in frequency-field facula algorithm. Experiment performance results from the effect of background and anomaly facula and so on. Integrates from high precision and center of gravity algorithm, frequency-field optical communication tracking method is designed. The method is immunity to the halation, optical aberration and optical communication link. The range of testing platform vibration less than two scalar NASDA satellite platform vibration, that is achievable the tracking test, and put forward optimization time segment.
To measure the wave-front aberration, the Shack-Hartmann(SH) wave front sensor(WFS) is used in most adaptive optics(AO) systems. The accuracy of the centoid(center of gravity) detecting of sub-images plays an importan...
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ISBN:
(纸本)9780819483836
To measure the wave-front aberration, the Shack-Hartmann(SH) wave front sensor(WFS) is used in most adaptive optics(AO) systems. The accuracy of the centoid(center of gravity) detecting of sub-images plays an important role in the performance of SHWFS. Normally the centriods of the point source spots are estimated to determine the local wave-front slopes by a center-of-gravity (CoG) algorithm. However the CoG algorithm suffers from several weaknesses. At first, there are few situations when a standard point source is available, such as situations with strong atmosphere disturbance and low flux. Secondly, CoG suffers significantly from CCD read-out noise. Instead of the traditional CoG, the correlation algorithm to estimate the wave-front slopes is used here, and the main characteristics of this method is analyzed. Analytical results predict this correlation approach presents better linear and robust performance. Moreover both simulation and experimental data from a point source based indoors experiment are carried out to verify the expected conclusions. The result agrees well with the simulation analysis.
It is widely accepted that the emergence of cognitive radio (CR) will lead to a wireless communication revolution. Spectrum sensing is one key process of CR, which makes effective use of scarce spectrum. Two novel sch...
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ISBN:
(纸本)9781424425198
It is widely accepted that the emergence of cognitive radio (CR) will lead to a wireless communication revolution. Spectrum sensing is one key process of CR, which makes effective use of scarce spectrum. Two novel schemes, clustering and locating schemes, are presented for spectrum sensing based on energy detection on the condition that there are multiple primary users in the cognitive radio network. Clustering scheme is used for estimating the number of primary users and dividing the secondary users into several groups based on their geographical position as well as received energy by my proposed iterative max-min theory, and then locates the position of primary user by locating scheme based on the center of gravity algorithm. These schemes work well when only geographic information and the amount of energy can be obtained. Finally, numerical analysis and simulation results of these schemes are provided. It is proved that the proposed criteria are practical and efficient in the absence of the type of primary signal and the amount of noise which are necessary for previous methods.
A novel design for an inexpensive depth of interaction capable detector for gamma-ray imaging has been developed. The design takes advantage of the strong correlation between the width of the scintillation light distr...
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A novel design for an inexpensive depth of interaction capable detector for gamma-ray imaging has been developed. The design takes advantage of the strong correlation between the width of the scintillation light distribution in monolithic crystals and the interaction depth of gamma-rays. We present in this work an inexpensive modification of the commonly used charge dividing circuits which enables the instantaneous and simultaneous computation of the second order moment of light distribution. This measure provides a good estimate for the depth of interaction and does not affect the determination of the position centroids and the energy release of gamma-ray impact. The method has been tested with a detector consisting of a monolithic LSO block sized 42 x 42 x 10 mm(3) and a position-sensitive photomultiplier tube H8500 from Hamamatsu. The mean spatial resolution of the detector was found to be 3.4 mm for the position centroids and 4.9 mm for the DOI. The best spatial resolutions were observed at the center of the detector and yielded 1.4 mm for the position centroids and 1.9 mm for the DOI. (C) 2008 Elsevier B.V. All rights reserved.
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