The research relevance is determined by the need to improve the processes of measurement of objects size in hard-to-reach conditions. In the modern industrial environment, where high measurement ...accuracy is critical for ensuring safety and maximizing the efficiency of production processes, the study of this topic is relevant in the context of rapid technological development and increased requirements for production quality. The study aims to evaluate the possibilities of using modern computer vision methods for measuring and reconstructing objects in difficult technical conditions, such as the enclosure of a water-water power reactor. The study employed 3D photogrammetry methods, including Depth from Stereo and Multi-View Stereo, as well as Structure from Motion methods. The study determined that modern computer vision methods, in particular machine learning methods, can be successfully used for measuring and reconstructing objects in hard-to-reach conditions. The study showed that the measurement accuracy can reach values close to 1 mm under ideal conditions and at a distance of 1.5 from the measuring device to the object. At the same time, the Multi-View Stereo method revealed greater uniformity of the spatial distribution of errors compared to the Depth from the Stereo method. In practice, in the conditions of real photos, the Multi-View Stereo method turned out to be more demanding to accurately determine the position of the camera. Due to its low demand for the exact coordinates of the cameras, the Depth from the Stereo method showed better results, showing less error in the measurements. The study highlighted the possibility of using the proposed method to distinguish fluctuations in the height of the surface of the object, which is important for further applications in the field of reactor maintenance and other areas of industry. The practical value of this research lies in the development and validation of methods for measuring and reconstructing objects in conditions where traditional methods become limited or impractical
We present a measurement of the cross sections for the associated production of a W boson with at least one heavy quark jet, b or c, in proton–antiproton collisions. Data corresponding to an ...integrated luminosity of 8.7 fb−1 recorded with the D0 detector at the Fermilab Tevatron pp¯ Collider at s=1.96 TeV are used to measure the cross sections differentially as a function of the jet transverse momenta in the range 20 to 150 GeV. These results are compared to calculations of perturbative QCD theory as well as predictions from Monte Carlo generators.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A
bstract
The production of beauty and charm quarks in
ep
interactions has been studied with the ZEUS detector at HERA for exchanged four-momentum squared 5
< Q
2
<
1000 GeV
2
using an integrated ...luminosity of 354 pb
−1
. The beauty and charm content in events with at least one jet have been extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. Differential cross sections as a function of
Q
2
, Bjorken
x
, jet trans- verse energy and pseudorapidity were measured and compared with next-to-leading-order QCD calculations. The beauty and charm contributions to the proton structure functions were extracted from the double-differential cross section as a function of
x
and
Q
2
. The running beauty-quark mass,
m
b
at the scale
m
b
, was determined from a QCD fit at next-to-leading order to HERA data for the first time and found to be
m
b
(
m
b
) = 4.07 ± 0.14 (fit)
− 0.07
+ 0.01
(mod.)
− 0.00
+ 0.05
(param.)
− 0.05
+ 0.08
(theo.) GeV.
We present the first measurements of the differential cross section dσ/dpTγ for the production of an isolated photon in association with at least two b-quark jets. The measurements consider photons ...with rapidities |yγ|<1.0 and transverse momenta 30<pTγ<200 GeV. The b-quark jets are required to have pTjet>15 GeV and |yjet|<1.5. The ratio of differential production cross sections for γ+2b-jets to γ+b-jet as a function of pTγ is also presented. The results are based on the proton–antiproton collision data at s=1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. The measured cross sections and their ratios are compared to the next-to-leading order perturbative QCD calculations as well as predictions based on the kT-factorization approach and those from the sherpa and pythia Monte Carlo event generators.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The reduced cross sections for e super(+)p deep inelastic scattering have been measured with the ZEUS detector at HERA at three different center-of-mass energies, 318, 251 and 225 GeV. The cross ...sections, measured double differentially in Bjorken x and the virtuality, Q super(2), were obtained in the region 0.13 < or = y < or = 0.75, where y denotes the inelasticity and 5 < or = Q super(2) < or = 110 GeV super(2). The proton structure functions F sub(2) and F sub(L) were extracted from the measured cross sections.
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Search for first-generation leptoquarks at HERA Abramowicz, H.; Aggarwal, R.; Arneodo, M. ...
Physical review. D, Particles, fields, gravitation, and cosmology,
07/2012, Volume:
86, Issue:
1
Journal Article
Open access
A search for first-generation leptoquarks was performed in electron-proton and positron-proton collisions recorded with the ZEUS detector at HERA in 2003-2007 using an integrated luminosity of 366 pb ...super(-1). Final states with an electron and jets or with missing transverse momentum and jets were analyzed, searching for resonances or other deviations from the standard model predictions. No evidence for any leptoquark signal was found. The data were combined with data previously taken at HERA, resulting in a total integrated luminosity of 498 pb super(-1). Limits on the Yukawa coupling, lambda, of leptoquarks were set as a function of the leptoquark mass for different leptoquark types within the Buchmuller-Ruckl-Wyler model. Leptoquarks with a coupling lambda = 0.3 are excluded for masses up to 699 GeV.
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