Browsing by Author "Li A"

Now showing 1 - 3 of 3
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    Indoor Particulate Matter Transfer in CNC Machining Workshop and The Influence of Ventilation Strategies—A Case Study
    (MDPI (Basel, Switzerland), 2023-04-04) Yao H; Qiu S; Lv Y; Wei S; Li A; Long Z; Wu W; Shen X; Daneshazarian R
    Particulate matter in Computer Numerical Control (CNC) machining workshop is harmful to workers’ health. This paper studies particulate matter transfer and the performance of various ventilation strategies in a CNC machining workshop. To obtain the boundary condition of the particle field, instruments were installed to obtain the particle size attenuation characteristics and source strength, respectively. The results show that the 99% cumulative mass concentration of particles is distributed within 1.5 μm, and the release rate of particles from the full enclosure. Next, the indoor flow field and particle field were simulated by numerical simulation with the measured boundary conditions. The working area’s age of air, particle concentration, and ventilation efficiency were compared between four displacement ventilation methods and one mixed ventilation method. The results show that the working area’s mean particle concentration and ventilation efficiency under longitudinal displacement ventilation is better than other methods. At the same time, the mean age of air is slightly worse. In addition, mixed ventilation can obtain lower mean age of air, but the particle concentration is higher in the working area. The bilateral longitudinal ventilation can be improved by placing axial circulation fans with vertical upward outlets in the center of the workshop.
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    Measurement of the polarizations of prompt and non-prompt [Formula presented] and ψ(2S) mesons produced in pp collisions at s=13TeV
    (Elsevier B.V., 2024-10-04) Hayrapetyan A; Tumasyan A; Adam W; Andrejkovic JW; Bergauer T; Chatterjee S; Damanakis K; Dragicevic M; Hussain PS; Jeitler M; Krammer N; Li A; Liko D; Mikulec I; Schieck J; Schöfbeck R; Schwarz D; Sonawane M; Templ S; Waltenberger W; Wulz CE; Darwish MR; Janssen T; Van Laer T; Van Mechelen P; Breugelmans N; D'Hondt J; Dansana S; De Moor A; Delcourt M; Heyen F; Lowette S; Makarenko I; Müller D; Tavernier S; Tytgat M; Van Onsem GP; Van Putte S; Vannerom D; Bilin B; Clerbaux B; Das AK; De Lentdecker G; Evard H; Favart L; Gianneios P; Jaramillo J; Khalilzadeh A; Khan FA; Lee K; Mahdavikhorrami M; Malara A; Paredes S; Shahzad MA; Thomas L; Vanden Bemden M; Vander Velde C; Vanlaer P; De Coen M; Dobur D; Gokbulut G; Hong Y; Knolle J; Lambrecht L; Marckx D; Mota Amarilo K; Samalan A; Skovpen K; Van Den Bossche N; van der Linden J; Wezenbeek L; Benecke A; Bethani A; Bruno G; Caputo C; De Favereau De Jeneret J; Delaere C; Donertas IS; Giammanco A; Guzel AO; Jain S; Lemaitre V; Lidrych J; Mastrapasqua P; Tran TT; Wertz S; Alves GA; Alves Gallo Pereira M; Coelho E; Correia Silva G; Hensel C; Menezes De Oliveira T; Mora Herrera C; Moraes A; Rebello Teles P; Soeiro M; Vilela Pereira A; Aldá Júnior WL; Barroso Ferreira Filho M; Brandao Malbouisson H; Doser M
    The polarizations of prompt and non-prompt [Formula presented] and ψ(2S) mesons are measured in proton-proton collisions at s=13 TeV, using data samples collected by the CMS experiment in 2017 and 2018, corresponding to a total integrated luminosity of 103.3fb−1. Based on the analysis of the dimuon decay angular distributions in the helicity frame, the polar anisotropy, λϑ, is measured as a function of the transverse momentum, pT, of the charmonium states, in the 25–120 and 20–100 GeV ranges for the [Formula presented] and ψ(2S), respectively. The non-prompt polarizations agree with predictions based on the hypothesis that, for pT≳25GeV, the non-prompt [Formula presented] and ψ(2S) are predominantly produced in two-body B meson decays. The prompt results clearly exclude strong transverse polarizations, even for pT exceeding 30 times the [Formula presented] mass, where λϑ tends to an asymptotic value around 0.3. Taken together with previous measurements, by CMS and LHCb at s=7 TeV, the prompt polarizations show a significant variation with pT, at low pT.
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    Search for a resonance decaying to a W boson and a photon in proton-proton collisions at s = 13 TeV using leptonic W boson decays
    (Springer Nature, 2024-09-25) Hayrapetyan A; Tumasyan A; Adam W; Andrejkovic JW; Bergauer T; Chatterjee S; Damanakis K; Dragicevic M; Hussain PS; Jeitler M; Krammer N; Li A; Liko D; Mikulec I; Schieck J; Schöfbeck R; Schwarz D; Sonawane M; Templ S; Waltenberger W; Wulz CE; Janssen T; Van Laer T; Van Mechelen P; Breugelmans N; D’Hondt J; Dansana S; De Moor A; Delcourt M; Heyen F; Lowette S; Makarenko I; Müller D; Tavernier S; Tytgat M; Van Onsem GP; Van Putte S; Vannerom D; Bilin B; Clerbaux B; Das AK; De Lentdecker G; Evard H; Favart L; Gianneios P; Jaramillo J; Khalilzadeh A; Khan FA; Lee K; Mahdavikhorrami M; Malara A; Paredes S; Shahzad MA; Thomas L; Vanden Bemden M; Vander Velde C; Vanlaer P; De Coen M; Dobur D; Gokbulut G; Hong Y; Knolle J; Lambrecht L; Marckx D; Mota Amarilo K; Samalan A; Skovpen K; Van Den Bossche N; van der Linden J; Wezenbeek L; Benecke A; Bethani A; Bruno G; Caputo C; De Favereau De Jeneret J; Delaere C; Donertas IS; Giammanco A; Guzel AO; Jain S; Lemaitre V; Lidrych J; Mastrapasqua P; Tran TT; Wertz S; Alves GA; Alves Gallo Pereira M; Coelho E; Correia Silva G; Hensel C; Menezes De Oliveira T; Mora Herrera C; Moraes A; Rebello Teles P; Soeiro M; Vilela Pereira A; Aldá Júnior WL; Barroso Ferreira Filho M; Brandao Malbouisson H; Carvalho W
    A search for a new charged particle X with mass between 0.3 and 2.0 TeV decaying to a W boson and a photon is presented, using proton-proton collision data at a center-of-mass energy of 13 TeV, collected by the CMS experiment and corresponding to an integrated luminosity of 138 fb−1. Particle X has electric charge ±1 and is assumed to have spin 0. The search is performed using the electron and muon decays of the W boson. No significant excess above the predicted background is observed. The upper limit at 95% confidence level on the product of the production cross section of the X and its branching fraction to a W boson and a photon is found to be 94 (137) fb for a 0.3 TeV resonance and 0.75 (0.81) fb for a 2.0 TeV resonance, for an X width-to-mass ratio of 0.01% (5%). This search presents the most stringent constraints to date on the existence of such resonances across the probed mass range. A statistical combination with an earlier study based on the hadronic decay mode of the W boson is also performed, and the upper limit at 95% confidence level for a 2.0 TeV resonance is reduced to 0.50 (0.63) fb for an X width-to-mass ratio of 0.01% (5%).