scholarly journals Analysis of Quadratic Surface Fitting for Subpixel Motion Extraction from Video Images

Author(s):  
Bian Xiong ◽  
Qinghua Zhang ◽  
Vincent Baltazart
2015 ◽  
Vol 21 (3) ◽  
pp. 624-636 ◽  
Author(s):  
FANG-SHII NING

Abstract:Geoidal undulation is the distance from the surface of an ellipsoid to the surface of a geoid measured along a line that is perpendicular to the ellipsoid. This paper describes how the geoidal undulation can be derived from the orthometric height, Global Navigation Satellite System geodetic height, and a surface model. Various surfaces fitting using the plane coordinates of the reference points and analysis with different buffers were used to determine the geoid undulation Taiwan. The results show that the quadratic surface model outperformed other surface models, yielding a buffer radius ranging from 15 to 25 km. According to the results, the accuracy of regional geoid undulation (city or state) can be improved through this process of surface fitting


Author(s):  
Tim Oliver ◽  
Akira Ishihara ◽  
Ken Jacobsen ◽  
Micah Dembo

In order to better understand the distribution of cell traction forces generated by rapidly locomoting cells, we have applied a mathematical analysis to our modified silicone rubber traction assay, based on the plane stress Green’s function of linear elasticity. To achieve this, we made crosslinked silicone rubber films into which we incorporated many more latex beads than previously possible (Figs. 1 and 6), using a modified airbrush. These films could be deformed by fish keratocytes, were virtually drift-free, and showed better than a 90% elastic recovery to micromanipulation (data not shown). Video images of cells locomoting on these films were recorded. From a pair of images representing the undisturbed and stressed states of the film, we recorded the cell’s outline and the associated displacements of bead centroids using Image-1 (Fig. 1). Next, using our own software, a mesh of quadrilaterals was plotted (Fig. 2) to represent the cell outline and to superimpose on the outline a traction density distribution. The net displacement of each bead in the film was calculated from centroid data and displayed with the mesh outline (Fig. 3).


2012 ◽  
Vol 6 (1) ◽  
pp. 47-63
Author(s):  
Stephen Pihlaja

Using membership categorization analysis, this article investigates membership categories in a YouTube video made by an Evangelical Christian in which he differentiates between “saved” and “religious” users. Analysis will take a discourse-centred, multimodal approach grounded in longitudinal observation, using analysis of video discourse to instruct analysis of video images and user comments. Findings will show that categorization is accomplished by using recognized categories with ambiguous descriptions of category-bound activities that include metaphors, such as “being hungry for God” and not “hanging out with atheists.” These categories are recognized by commenters on the video, but the category bound activities applied to the category members are disputed. Findings will also show that scriptural reference plays an important role in categorization in the video, drawing on direct Bible quotes as well as paraphrases of key passages.


2020 ◽  
pp. 26-32
Author(s):  
VLADIMIR V KIRSANOV VLADIMIR V ◽  

The problems of the digitalization of livestock enterprises are closely related to the construction of models and algorithms describing the functioning of individual technological processes and subsystems united by a common control system. Based on the cluster approach, three groups of tasks for the intellectualization and digitalization of objects in livestock breeding are formulated: 1) recognition of images of biological objects and models of their group and individual behavior, 2) genomic assessment of farm animals, prediction of their genetic potential, with the possibility of better adaptation to technologies and specifi c economic conditions, 3) multi-agent management of automated and robotic technical means. The authors initialized the video images of biological objects, developed a structural and functional model of a complex biotechnical system “Man-Machine-Animal”, including automated workstations of key specialists, signal receiving-and-transmitting base stations, technological modules for animal service (feeding, watering, milking, microclimate, etc.), representing local biotechnical systems. The paper presents a structural-and-logistic “funnel” model of a livestock farm functioning. The model includes vectors of incoming material fl ows, outgoing production fl ows and outgoing byproducts (production waste) described using appropriate formalizations. The authors provide the structural typifi cation of technological modules and subsystems for their mathematical analysis and subsequent digital transformation of livestock farms.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Julia Woitischek ◽  
Nicola Mingotti ◽  
Marie Edmonds ◽  
Andrew W. Woods

AbstractMany of the standard volcanic gas flux measurement approaches involve absorption spectroscopy in combination with wind speed measurements. Here, we present a new method using video images of volcanic plumes to measure the speed of convective structures combined with classical plume theory to estimate volcanic fluxes. We apply the method to a nearly vertical gas plume at Villarrica Volcano, Chile, and a wind-blown gas plume at Mount Etna, Italy. Our estimates of the gas fluxes are consistent in magnitude with previous reported fluxes obtained by spectroscopy and electrochemical sensors for these volcanoes. Compared to conventional gas flux measurement techniques focusing on SO2, our new model also has the potential to be used for sulfur-poor plumes in hydrothermal systems because it estimates the H2O flux.


Author(s):  
Raymond Berry

AbstractThe bed bug, Cimex lectularius L., is a common ectoparasite found to live among its vertebrate hosts. Antennal segments in bugs are critical for sensing multiple cues in the environment for survival. To determine whether the thermo receptors of bed bugs are located on their antennae; innovative bioassays were created to observe the choice between heated and unheated stimuli and to characterize the response of bugs to a heat source. Additionally, the effect of complete antenectomized segments on heat detection were evaluated. Heat, carbon dioxide, and moisture are cues that are found to activate bed bug behavior; a temperature at 38°C was used to assess the direction/degree at which the insect reacts to the change in distance from said stimulus. Using a lightweight spherical ball suspended by air through a vacuum tube, bed bugs and other insects are able to move in 360° while on a stationary point. Noldus EthoVision XT was used to capture video images and to track the bed bugs during 5-min bioassays. A bioassay was created using four Petri dish arenas to observe bed bug attraction to heat based on antennae segments at 40°C. The purpose of this study was to evaluate the effects of heat on complete antenectomized segments of the antennae. The results in this experiment suggest that bed bugs detect and are attracted to heat modulated by nutritional status. Learning the involvement of antennae segments in heat detection will help identify the location and role of thermoreceptors for bed bug host interaction.


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