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For the bad accuracy and high costs of the transit passenger traffic statistics, we propose a machine vision-based algorithm. As the body parts of the human often occur overlap in congested conditions, the algorithm in this study uses the overhead image of the passengers as the statistic targets. The Histogram of Oriented Gradient (HOG) combined with the Support Vector Machine (SVM) is adopted in this study. Compared with the traditional methods, the accuracy and the speed of the detection stage have been greatly improved. The algorithm can be divided into three steps: the target detection, target tracking and statistics. Based on the machine learning methods, it first extracts the head HOG feature, and then uses the SVM algorithm to train feature sets to get a classifier based on passenger heads. We choose the Camshift as the tracking algorithm. In order to improve the correct trajectory, it must be fuse the target detection and the target tracking. Through the rules of the passengers to alight, we can get the number of passengers automatically.

This paper demonstrates an 8 × 8 Butler Matrix design that does not employ cross-overs. The Butler Matrix was manufactured on a single side of Printed Circuit Board (PCB) and is intended for use with a low-profile C-band directional antenna array. This solution provides an effective methodology for electronically switching beam states of a planner distributed array where typical applications of active phase shifters would either be cost prohibitive or are unnecessary to meet the technical requirements. This design makes use of a series of quadrature hybrid couplers made up of microstrip line circuit board. Test results show that the Matrix efficiently produces the necessary power and phase distribution to each output port allowing the antenna array to show 8 distinct beam states.

To help with long range coverage, minimal interference, and reduced energy requirements, recently there have been growing interest in incorporating directional antenna arrays in wireless communication networks. In this paper, we describe the challenges and opportunities in developing directional wireless communication networks and present innovative options that could facilitate this development, with focus on changes in the physical layer and minimal impact on the higher layers in the ISO model. Example of such research activities in the antenna design area is described in details. Specifically, a broadband, dual polarization, and very narrow beam (

This Electronic Guidance Case(EGC) is a design patterns of Guidance Case based on web, under this mode, the teachers control the state of student learning instantaneously and can make the corresponding “teaching” contents, the methods of choice and change, while they can also make full and effective use of the factors of educational resources, including the factors of the students themselves, the scenes of the design task, knowledge links and other learning support services, so that their ability of thinking and innovating will be developed well in the group cooperation and self-exploration activities. Through the literature and theoretical study methods, put forward the necessity of researching EGC, and compared to traditional design patterns of plan, illustrate the theoretical basis of the design patterns of EGC electronics modules of the plan; build up basic processes and process model of EGC. Asynchronous learning respect for individual learning differences and realize independent learning, all of which profoundly incarnate the concept of student-centered Education.

Aimed at the disadvantage of current research of shill bidding with different online auctions types, in this paper, Applying decision analysis method and game theory, firstly, we research the bidder's optimal biding Strategy on English Auction, First-price Sealed-bid Auction and Second-price sealed-bid auction with Shill Bidding, respectively. Secondly, we use bidder's expected gain and seller's revenue as a basis to compare these three important auctions types, and interpret some bidding behavior in practice.

In the paper, an optimized data network security system based on 4G is designed. Abiding by the information system safety theory, the paper follows the methods of systems analysis and overall balance, and raises the principles systematically that by study and analyze the network venture of Power Supply Bureau in the process of informatization. And, according to the No.30 order of The State Economic and Trade Committee, the Power Supply Bureau data network is designed. The project it referred is based on the real requirement and technology practice when rebuilding Supply Bureau network, and bring out the guidance effect for generalizing the new unified operation system, planning the network flat and disposing the network safe policy.

A Ka band radial waveguide power divider has been designed for two-dimensional scanning phased array antennas. A measured result of 24% frequency bandwidth has been obtained for -20 dB return loss. Simulated results shows that the coupling amount of energy from a radial waveguide power divider to phase shifters can be controlled to meet the sidelobe requirements. Sensitivity studies for the coupling shows the tolerable amplitude errors for mass production. The coupling design results need to be verified by measurement results.

A mechanical microswitch has been fabricated by single crystal silicon bulk micromachining on a glass substrate. The mechanical part of the device has superior mechanical reliability and can be applied to a phased-array antenna, since the glass substrate can be easily extended to a large area, accommodating a large number of elements on it. A fabricated device was measured to have less than 0.2 dB of on-state insertion loss and higher than 13 dB of off-state isolation at 30 GHz.

This paper checks the accuracy of physical optics (PO) as applied to the scattering of dipole waves by a finite size surface which is composed of strips on a grounded dielectric slab. By using the closed form expressions of reflected waves from the surface, the PO calculation can be conducted straightforwardly. Since the reflection coefficients are obtained for a local plain wave and an infinite slab, considerable errors are expected for the dipole and the rapid curvature of the strip patterns. It is pointed out that for the straight patterns of strips, PO is applicable for the dipoles in at a distance of more than 0.5 wavelength from the surface. For the portion of the surface where the incident electric fields are perpendicular to the strips, larger errors are observed. The reason for this may be the excitation of surface waves. The accuracy of the PO is evaluated by comparing the calculation and measurement of the radiation patterns of a half-wavelength dipole antenna vertically mounted above the circular disk of strips loaded with a grounded dielectric slab as a reflector.

Artificial soft and hard surfaces are intensively applied for antenna engineering. The importance of this kind of surface in antenna and propagation studies makes accurate and simple electromagnetic expressions necessary. The purpose of the present paper is to analyze the reflection coefficients of the strip gratings on a dielectric slab over a ground plane and by using the low frequency assumption, the simple closed form expressions of reflection coefficients are derived. These are based upon the singular integral equations approach developed for the analyses of gratings. We can use the simple expressions to design hard and soft surfaces artificially.

Low orbit global satellite communication systems require low cost user terminals. A low cost microstrip patch phased array antenna is the most possible choice. For a wide frequency band and wide scan angle microstrip patch phased array antenna, the use of a thick patch substrate results in an increased excitation of surface waves. The mutual coupling effects caused by these surface waves have to be taken into account in the design. This is especially true for the design of microstrip patch arrays for future satellite communication systems, which will consist of several hundreds of microstrip patch elements. This article introduces a simple calculation procedure of the active reactive coefficients and radiation patterns of a finite size element microstrip patch phased array. The active impedance is calculated by matrix summation of isolated element impedance and mutual coupling between any two elements. Once the active element impedance is calculated, the radiation pattern can be calculated using the excitation voltage of each element. Some calculated results are shown.

The simple and closed form expressions for the reflection coefficients of the dielectric slab loaded with a periodic array of strips over a ground plane are utilized and two special polarization angles are derived for which the polarization direction of the reflected wave remains unchanged. The physical optics (PO) diffraction coefficient of an isotropic surface can be used in terms of two sets of coefficients for the special polarization angle of the anisotropic surfaces.

The antenna presented uses vertical linear polarization and scans from -45/spl deg/ to +45/spl deg/ in the azimuth plane and has a fixed cosecant squared beam in the elevation plane. This paper presents the performance and measurement results for a 1-D scanning phased array antenna with a 16/spl times/16 element configuration. Gain is measured to be 22.5 dBi at 0/spl deg/ scan. The measured radiation patterns, gains and active return loss for scans from -45/spl deg/ to +45/spl deg/ in 5/spl deg/ steps demonstrate consistent patterns with no grating lobes and blindness. This performance is attributed to minimum mutual coupling effects of this microstrip patch array.

Ideally soft and hard surfaces can be obtained by transversely and longitudinally oriented conducting strips on a grounded dielectric slab, respectively. The importance of this kind of surfaces in antenna and propagation makes their accurate and simple electromagnetic expressions necessary. In this communication, the expressions are derived by using the low frequency assumption. The results of our expressions are compared numerically with that by Point Matching Method (PMM). We have calculated and discussed the structures used as the soft and hard surfaces, and the bandwidth of the reflection coefficient phase.