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Point cloud data of complex product with small changes of surface has narrow data range, high spatial relativity and smooth data change. It is not sensitive to feature extraction and shape recognition. Point cloud data enhancement based on layer connected region is proposed. The two-dimensional matrix is calculated to describe point cloud data reflecting the product shape and spacial relationship...
A high-current-density, long life and uniformemission cathode is a key requirement for a THz-VED. Using a new synthesis approach Sc2O3 doped W-nanoparticles were made to fabricate cathode, which is believed to play a dominant role for above application. The fabrication details along with the emission results will be presented.
Fringe effects of electric field distribution near the FEA surface in diode configuration are studied by mathematical modelling. Different anode shapes are considered: plane anode and spherical anode. Modelling results of surface electric field distribution are presented. The spherical shape of anode allows higher voltage (and higher field emission current) without destructive arcs risk.
Traditional technology of experimental modal analysis bases on the known input and output signals, and utilizes integrated information of both the excitation and responses to identify the modal parameter. In most of the actual conditions, only the response data is measurable while excitations are unknown. Thus modal parameter must be extracted only from responses. In allusion to this limitation, this...
Reduction of radar cross section (RCS) is one of the most desirable features for fighter airplanes. As the reduction in RCS reduces the detectability of the object, therefore its reduction is of great importance for military and defense applications. RCS depends on a number of parameters including shape, orientation, operating frequency, aspect angle, permittivity and permeability of the medium, transmitted...
Article deals with current situation of the histogram use. Overwhelming majority of ELINT systems applies histogram depiction in their analytic displays. Significant majority of distinguished radar signals experts use their advantageous function. This contribution shows breaking approach in histogram description via Gaussian function. Particular parts are aimed into creation of data library. This...
A demonstration is made of the high-speed real-time image processing capabilities of the SCAMP-5 vision chip. The device provides a software-programmable 256×256 pixel-parallel SIMD processor array. In the example application, the IC can determine dimensions and the location of a single object, at a sustained rate of 100,000fps. At 30,000fps, the chip can return the same metrics from 5 objects. This...
Voronoi diagrams are powerful for solving spatial problems among particles with different sizes. In particular, the Voronoi diagram of spheres, also called the additively-weighted Voronoi diagram, has proven its powerful capability for solving molecular biology/material science problems in an unified framework. Beta-complex is a generalization of (weighted) alpha-complex and they share similarities...
The development of automated measurement systems for monitoring basic functional geometries arises as a response to the increasing automation of manufacture. The paper describes the optimization of the grid increment to be used in the algorithm established by the authors to automatically recognize 3D geometries. Differential geometry was used to determine Gaussian and mean local curvatures of surfaces...
The given is the review of the basic result of experimental investigations of the electron work function of sodium. It has been shown that (i) existing data are a few and obtained in narrow temperature limits, (ii) electron work function of sodium at negative temperatures is reported in just several papers, (iii) the temperature dependence of electron work function does not reveal any noticeable breaks...
Caudal fin plays significant role in the swimming of bony fishes. It has often been considered as a simple two-dimensional propulsive surface that generates forces in the horizontal plane. However, fish caudal fin has complex origami structures, and is able to produce multiple three-dimensional (3D) kinematics. Based on the biological data from Lauder lab at Harvard University, we developed a multi-material...
Aiming at a class of nonlinear stochastic systems with additive Gaussian White noise and the polynomial nonlinear function we propose a shape control technique for probability density function (PDF) of the state variable. Controlling the PDF shape requires to design a controller making the PDF shape as close as possible to the desired PDF, and this actually is to determine the parameters of the controller...
In this paper, a novel fully automatic method of extraction of lung parenchyma is presented. Combining the iterative gray-level thresholds selection and the pulmonary regions extraction with error detection in 2D image, seed points and threshold are fast determined. In consequence, the pulmonary airspace is detected with 3D region growing method. Two steps airways segmentation with additional shape...
Vision based road detection is a key technique in Autonomous driving and Advance Drive Assistance System. We propose an approach for vision-based road detection which exploits road shape prior, color consistence representation and discrimination analysis. Firstly, road shape prior probability map is constructed from available road images which have been annotated by matching and classifying of road...
Donor cell injection is a significant technique in nuclear transfer and many other biological operations. Recent achievements in biology and biomedicine demonstrate great potential of these micromanipulation technologies. Traditionally, these operations are done manually, which require high professional skills and are of low repeatability. To overcome these disadvantages, automatic operation of this...
This research presented a geometric CAPTCHA which was not created from images in any database, but it is an image of a geometric shape that randomly generated from a program and its edge was incomplete. Geometric CAPTCHAs were tested with users to identify the number of angles from a shape and to do a simple calculation. Users must type a right answer to pass the CAPTCHA test. Geometric CAPTCHAs were...
This paper addresses the problem of group path planning while maintaining group coherence and persistence. Group coherence ensures that a group minimizes both longitudinal and lateral dispersion, and is achieved with the introduction of a deformation penalty to the cost formulation. When the deformation penalty is significantly high, a group may split and later merge. Group persistence is modeled...
The unique characteristics of origami to realize 3-D shape from 2-D patterns have been fascinating many researchers and engineers. This paper presents a fabrication of origami patterned fabric wheels that can deform and change the radius of the wheels. PVC segments are enclosed in the fabrics to build a tough and foldable structure. A special cable driven mechanism was designed to allow the wheels...
Automatic plant identification via computer vision techniques has been greatly important for a number of professionals, such as environmental protectors, land managers, and foresters. In this paper, a novel leaf image recognition technique via sparse representation is proposed for automatic plant identification. In order to model leaf images, we learn an overcomplete dictionary for sparsely representing...
For electrical grid systems with significant levels of intermittent renewables it will be essential to shape aggregate demand to match periods of cheap renewable supply. For example, the Irish grid will have approximately 40% of its electricity coming from intermittent wind turbines by 2020. Currently at 18%, the turbines are curtailed when they reach 50% of instantaneous supply for control reasons...
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