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21.
The main goal of this paper is the design of a novel and robust methodology for calibrating cameras from a single image in sport scenarios, such as a soccer field, or a basketball or tennis court. In these sport scenarios, the only references we use to calibrate the camera are the lines and circles delimiting the different regions. The first problem we address is the extraction of image primitives, including the challenging problems of shaded regions and lens distortion. From these primitives, we automatically recognise the location of the sport court in the scene by estimating the homography which matches the actual court with its projection onto the image. This is achieved even when only a few primitives are available. Finally, from this homography, we recover the camera calibration parameters. In particular, we estimate the focal length as well as the position and orientation in the 3D space. We present some experiments on models and real courts which illustrate the accuracy of the proposed methodology. 相似文献
22.
Summary The Stefan-Winkelmann diffusion technique has been used to determine vapor pressures of high boiling point compound-solvents mixtures. Data are reported at a temperature of 67°C for the mixtures polyphenyl ether (6 rings) — benzene and carbowax 1500 — benzene and at a temperature of 100°C for the mixtures polyphenyl ether (6 rings) — toluene and tricresylphosphate-toluene. The range of concentration is only limited by the appearance of a solid phase, and results are in good agreement with those determined by vapor pressure osmometry.Nomenclature A
Vapour source
- B
Flowing gas phase
- c
Concentration, g-mol/cm3
- DAB
Molecular diffusion coefficient, cm2/s
- hi
Total interface depth, cm
- K
Parameter defined by equation (6), dimensionless
- I
Polymer or high boiling point compound
- MA
Molecular weight
- NAZ
Molar flux, g-mol/(cm2) (s)
- PA
Partial pressure at the interface, atm
- P
Total pressure, atm
- R
Gas constant, (atm) (cm3) / (°K) (g-mol)
- T
Temperature, °K
- t
Time, s
- YA
Molar fraction at the interface, dimensionless
- zo
Initial interface depth, cm
- zi
Drop of the interface depth, cm
- z
Interface position
Greek Letters A
Density of the liquid phase, g/cm3 相似文献
23.
Robert K. Vander Meer Francisco Alvarez Clifford S. Lofgren 《Journal of chemical ecology》1988,14(3):825-838
TheSolenopsis invicta trail pheromone is synthesized by the Dufour's gland and is released through the sting apparatus. The recruitment subcategory of theS. invicta trail pheromone was shown to be composed of a mixture of the orientation pheromone, (Z,E)--farnesene and an unidentified homosesquiterpene consisting of three rings and one double bond (C-1). C-1 is present in worker Dufour's glands at only 75 pg per worker equivalent. This is the first report that demonstrates that different exocrine products from the same gland control different subcategories of behavior related to mass recruitment. 相似文献
24.
Hydrolyzed olive pit residues from the production of furfural were ammoniated to obtain a nitrogenenriched humic fertilizer. Samples had been previously oxidized with nitric acid. The oxidized samples were further ammoniated in a batch reactor in the following range of experimental conditions: T = 80–210°C,
, solid/liquid ratio, S/L = 0.5–2.8 w/w and reaction time, t = 1–4 h.Planning of experiments was made by statistical design and results were fitted by multiple non-lineal regression polynomials. The product consists of two fractions: a water soluble fraction which contains most of the nitrogen (10–13 wt%) and a solid fraction with a very low nitrogen content (<4.0 wt%), which is likely to be fixed during the oxidation step. The soluble fraction can be used as a humic fertilizer and the solid product as a soil conditioner. 相似文献
25.
26.
Gain measurements are carried out for different lengths of three types of erbium-doped silica fiber with different pump powers at 1480 nm. From these measurements a relation is established for each type of fiber between gain and the attenuation factor of the pump power. This relation is in complete agreement with the one predicted by an analytic model based on overlapping factors, which makes it possible to obtain methods for the experimental characterization of doped fibers. 相似文献
27.
Quality control and safety related issues have become more and more important in industrial production of high added value products and chemical specialities during last years. In this regard, many successful applications of multivariate statistical process control (MSPC) for monitoring and diagnosis of batch processes have been presented. It is a common industrial practice to monitor the batch progress by exploiting the information contained in a historical database of successful batches using projection techniques such as principal components analysis (PCA), partial least squares (PLS) and independent component analysis (ICA). In this work, a new MSPC strategy for batch process monitoring is presented. Its distinctive feature is that it works in the space of the original variables. The technique uses only the T2-statistic for detection and identification purposes. The identification of the set of observations that signal the fault is accomplished by decomposing the T2-statistic as a unique sum of each variable contribution. Performance comparisons among the proposed strategy and the most popular PCA-based approaches are carried out by simulation of polymerization and penicillin cultivation batch processes. Results show that the new approach can be successfully applied to monitor this kind of processes since it works very well during both fault detection and identification stages. 相似文献
28.
A planar voltammetric sensor array for use in an electronic tongue was fabricated using a combination of microfabrication techniques. The techniques of e-beam evaporation and pulsed laser deposition were applied to prepare a device that contained all of the electrodes integrated on a silicon die (6 mm × 6 mm). The working electrodes were metals gold, platinum, iridium and rhodium. They were characterized by SEM and EDX, and by electrochemical investigation of the packaged dies with cyclic voltammetry in solutions of sulfuric acid and of ferrocene carboxylic acid in aqueous buffer solution. The robustness and reproducibility of the devices were assessed by potential cycling in acid solution. 相似文献
29.
Marya Wani Vishnupriya Raghavan Dolphy Abraham Virginia Kleist 《Information Systems Frontiers》2017,19(4):769-785
Travel websites are extensively used by travelers for their travel bookings, yet little is known about the hedonic effectiveness of such experiences for the customer. The end users of these websites are customers who may not always be sophisticated information system (IS) users. Further, traditional utility based measures of customer evaluation are dated with respect to the interactive nature of the technology in use and the hedonic benefits that may result from the use of the technology. The evaluation of IS needs to include hedonic measures facilitated by the interactive technology in addition to the traditional utility based measures. We propose and test an evaluation model for retail travel websites that combines the traditional utility based measures with hedonic measures which collectively create a more comprehensive measure for the IS evaluation of consumer focused websites. Thus rooted in theory, the model extends DeLone and McLean’s model of IS Success by adding the construct of User Experience. The model was tested on a sample of 255 customers of travel websites targeted at the Indian market. The results indicate that both utility based and hedonic measures are important factors for customer IS (travel website in this study) evaluation. The larger implications for theory and practice of IS evaluation are explained. 相似文献
30.
Luis Alvarez‐Icaza Oscar Rosas‐Jaimes María Elena Lárraga 《Asian journal of control》2017,19(2):494-509
A framework for stability analysis of local on‐ramp metering control strategies based on the cell transmission model is presented. Within this framework, it is possible to formulate Lyapunov and input‐state stability results for on‐ramp metering control strategies in an open section of highway with on‐ramps. Using this analysis, recommendations for the design of on‐ramp metering control laws set points are derived. Two examples on the use of such analysis are presented. One deals with the stability analysis of a local on‐ramp metering control law and the other with the design of a disturbance observer that, used in combination with the local on‐ramp metering control law, provides a more robust response to traffic regulation. Simulation results are included that confirm the possibility of using this framework to test the impact of local on‐ramp metering control strategies. 相似文献