Bottomonium observables in an open quantum system using the quantum trajectories method

We solve the Lindblad equation describing the Brownian motion of a Coulombic heavy quark-antiquark pair in a strongly coupled quark gluon plasma using the Monte Carlo wave function method. The Lindblad equation has been derived in the framework of pNRQCD and fully accounts for the quantum and non-Abelian nature of the system. The hydrodynamics of the plasma is realistically implemented through a 3+1D dissipative hydrodynamics code. We compute the bottomonium nuclear modification factor and elliptic flow and compare with the most recent LHC data. The computation does not rely on any free parameter, as it depends on two transport coefficients that have been evaluated independently in lattice QCD. Our final results, which include late-time feed down of excited states, agree well with the available data from LHC 5.02 TeV PbPb collisions.

Evaluation of Seismic Response Modification Factor (R) for Moderate-Rise RC Buildings with Vertical Irregular Configurations

Most international design codes consider the nonlinear seismic performance of a structure by the concept of reduction/modification factor (R). Then, an elastic static force-based method can be normally used for seismic design to create earthquake resistant RC buildings. The response modification factor (R) is sensitive to many aspects such as overall ductility, over-strength, damping, and redundancy levels. Indeed, these factors are severely affected by geometric irregularity of the structural system. So, R-value does not become a constant number for the all types of structures with the same lateral load resisting system, as many standard codes noted. It depends on types, combination, and degrees of geometric vertical irregularity. This research assesses the actual values of R for regular and familiar vertical irregularity cases in RC buildings with moment-resisting frames (MRF) systems. Also, it takes into account the reduction percent that may occurs in R-value due to these studied vertical irregularities. The vertical irregularity cases, such as set-back and soft story, are essentially needed to be studied greater than ever due to the wide propagation of these types of buildings in Egypt, recently. In addition, the potential analytical methods that may be used to calculate R-value in comparison with Egyptian code’s value. Nonlinear static pushover analysis is carried out using ETABS via three-dimensional numerical models. The findings prove that vertical irregular models have poor seismic capacities, in comparison with regular one, due to their sudden change in lateral stiffness than that with regular aspect. So, the response modification factor (R) must be re-calculated or even scaled-down before design stage with 15% and 25% for single and combined vertical irregularity, respectively. In addition, this investigation derives a vital equation between R values with vertical irregularity ratios in each studied model. This equation shall be a guide for seismic design codes, structural design engineers, and researchers. Accordingly, the response modification factor R does not become a fixed value regardless vertical irregularity aspects of the buildings, but it has a variable value that depend on their inelastic seismic performance of the lateral load resisting systems.

Prediction Method for Condensation Heat Transfer in the Presence of Non-condensable Gas for CFD Applications

The objective of this study was to present a prediction method for condensation heat transfer in the presence of non-condensable gas (air or nitrogen) for CFD (computational fluid dynamics) analyses, where physical quantities in the computational cells in contact with the structural wall are generally used. First by using existing temperature distributions T(y) in the turbulent boundary layer along a flat plate as functions of the distance y from the condensation surface, we evaluated the distribution of condensation heat flux qc,pre(y) from the gradient of steam concentration, we derived a modification factor η(y+) as a function of the dimensionless distance y+ to obtain a good agreement with qc,cal calculated by the qc correlation defined by using the bulk quantities; and we obtained qc,mod(y)/qc,cal = 0.90-1.10 for the region of y+ > 17. Second we modified the local Sherwood number Sh(x) for flat plates for the boundary layer thickness d and obtained the function Sh(d). An existing qc correlation for flat plates as a function of Sh(d) was applied to predict the distribution of the local value qc,pre(y), and qc,pre(y)/qc,cal = 0.95-1.15 in the best case was obtained for the region of y+ > 30. Finally a correlation of the local Sherwood number Sh(y) was derived from the temperature distributions T(y) as a function of the local Reynolds number Re(y).

Measurement of J/ψ production cross-sections in pp collisions at $$ \sqrt{s} $$ = 5 TeV

The production cross-sections of J/ψ mesons in proton-proton collisions at a centre-of-mass energy of $$ \sqrt{s} $$ s = 5 TeV are measured using a data sample corresponding to an integrated luminosity of 9.13 ± 0.18 pb−1, collected by the LHCb experiment. The cross-sections are measured differentially as a function of transverse momentum, pT, and rapidity, y, and separately for J/ψ mesons produced promptly and from beauty hadron decays (nonprompt). With the assumption of unpolarised J/ψ mesons, the production cross-sections integrated over the kinematic range 0 < pT< 20 GeV/c and 2.0 < y < 4.5 are$$ {\displaystyle \begin{array}{c}{\sigma}_{\mathrm{prompt}}\ J/\psi =8.154\pm 0.010\pm 0.283\ \upmu \mathrm{b},\\ {}{\sigma}_{\mathrm{nonprompt}}\ J/\psi =0.820\pm 0.003\pm 0.034\ \upmu \mathrm{b},\end{array}} $$ σ prompt J / ψ = 8.154 ± 0.010 ± 0.283 μb , σ nonprompt J / ψ = 0.820 ± 0.003 ± 0.034 μb , where the first uncertainties are statistical and the second systematic. These cross-sections are compared with those at $$ \sqrt{s} $$ s = 8 TeV and 13 TeV, and are used to update the measurement of the nuclear modification factor in proton-lead collisions for J/ψ mesons at a centre-of-mass energy per nucleon pair of $$ \sqrt{s_{\mathrm{NN}}} $$ s NN = 5 TeV. The results are compared with theoretical predictions.

EVALUASI KINERJA STRUKTUR DUAL SYSTEM DENGAN BELT TRUSS

In structural engineering applications, the limit of building deflection or interstory drift is an important issue. In high-rise buildings that are more than or equal to 60 floors in the current era, systems are used in the structure of the building. The function of the Belt Truss is to reduce the deflection that occurs in the building by converting the building's overturning moment into the axial force of the exterior column. The Belt Truss structure itself can use reinforced concrete structures and steel structures. Because the Belt Truss structure is an innovation in the world of structural engineering, the parameter values for earthquake loads are not listed in the applicable Building Planning Standards. The standard for earthquake-resistant building regulations requires the parameters of Response Modification Factor (R), Overstrength Factor (Ωo), and Deflection Magnification (Cd) for determining earthquake loads. Because the parameters on the Belt Truss structure are not listed in the Standard for Earthquake Resistant Building Regulations, a study of the earthquake load parameters on the Belt Truss structure was carried out. The method used in this research is a literature study using Pushover Load Analysis according to ATC - 40 and FEMA 356. Keywords: Belt Truss, Dual System; ATC – 40; FEMA 356; Response Modification Factor (R); Overstrength Factor (Ωo); and Deflection Magnification (Cd) AbstrakDalam aplikasi rekayasa struktur gedung, batasan defleksi bangunan atau interstory drift adalah masalah penting. Pada bangunan tinggi yang lebih dari atau sama dengan 60 lantai pada era sekarang sudah menggunakan sistem pada struktur bangunan tersebut. Fungsi dari Belt Truss tersebut berguna untuk mengurangi defleksi yang terjadi pada bangunan dengan mengkonvesi momen guling bangunan menjadi gaya aksial kolom eksterior. Struktur Belt Truss sendiri materialnya bisa menggunakan struktur beton bertulang dan struktur baja. Karena struktur Belt Truss merupakan inovasi pada dunia rekayasa struktur, maka nilai parameter beban gempa tidak tercantum pada Standar Peraturan Perencanaan Bangunan yang berlaku. Standart Peraturan Bangunan tahan gempa diperlukan parameter – parameter Faktor Modifikasi Respon (R), Faktor Kuat Lebih (Ωo), dan Perbesaran Defleksi (Cd) untuk penentuan beban gempa. Dikarenakan parameter pada struktur Belt Truss tidak tercantum pada Standar Peraturan Bangunan Tahan Gempa, maka dilakukan penelitian parameter-parameter beban gempa pada struktur Belt Truss tersebut. Metode yang digunakan dalam penelitian ini adalah studi literatur dengan menggunakan analisa Beban Dorong Pushover Analysis sesuai ATC - 40 dan FEMA 356.

Evaluation of NSP and MPA Methods to Optimize Special Truss Moment Frames (STMF) Using Island Genetic Algorithm

The purpose of the present study is to evaluate the Pushover (NSP) and Modal Pushover (MPA) analysis methods in optimizing Special Truss Moment Frames (STMF) using island genetic algorithm. For this purpose, the optimization program is written and developed in Matlab software, and OpenSees software is used for structural analysis. The design variables of truss arrangement, cross section of members, truss height values and length of special zone of truss moment frame are considered. The constraints of the optimization problem are based on the rules and restrictions of AISC341-16. Case studies were performed on five frames of 3, 6, 9, 12 and 15 stories with a story height of 3 meters and span length of 18 meters with the aim of minimizing weight and maximizing the response modification factor. The results of these analyses are compared with nonlinear dynamic time history analyses as the most accurate method available, which could be used to finally identify and introduce the most efficient method in these structures. The MPA method was able to show better performance than the NSP method in estimating the maximum response of the structure. Despite the excellent performance of this method, Evaluation of numerical results of this study indicates the non-economic nature of MPA method for low-rise structures, and the acceptable efficiency of this method for medium-height to high-rise structures.