A model with vectorlike fermions and U(1)XU(1)_X symmetry: CKM unitarity, b→sb \rightarrow s transitions, and prospect at Belle II

To address the muon $g-2$ anomaly and the violation of the lepton flavor universality in the semileptonic decays of $B$ mesons, B\'elanger, Delaunay, and Westhoff introduced a new sector consisting of vectorlike fermions and two scalar charged under an extra $U(1)_X$ gauge symmetry. The exotic Yukawa interactions in this model lead to the quark mixing responsible for the additional contributions to the flavor changing neutral currents in $B$-meson decays. In this paper, we derive the analytic expression of the new physics contributions to the Wilson coefficient $C_7$ in the effective Hamiltonian. By calculating the branching ratio of the inclusive radiative $B$ decay, the impact of current experimental data of the $b \rightarrow s \gamma$ transition on the model and the future prospect at the Belle II experiment are investigated. Taking into account the recent data on the CKM unitarity violation, the updated constraints on the flavor observables relevant to the $b \rightarrow s$ transitions, and the perturbation limits of the couplings, the viable parameter regions of the model are identified.Comment: 28 pages, 14 figure

Muon g−2g-2 and semileptonic BB decays in B\'elanger-Delaunay-Westhoff model with gauge kinetic mixing

In the model proposed by B\'elanger, Delaunay and Westhoff (BDW), a new sector consisted of vectorlike fermions and two complex scalars is charged under an extra Abelian symmetry $U(1)_X$. In this paper, we generalize the BDW model by introducing the kinetic mixing between the $U(1)_X$ and the standard model $U(1)_Y$ gauge fields. The new physics contributions to the muon anomalous magnetic moment and the Wilson coefficients $C_{9,10}^{(')}$ are obtained analytically. We have explored the free parameter space of the model, taking into account various constraints on the muon $g-2$ using recent data from the E989 experiment at Fermilab, the lepton universality violation in terms of $R_K$ and $R_{K^*}$, and the branching ratios of the semileptonic decays, $B^+ \rightarrow K^+ \mu^+ \mu^-$ and $B^0 \rightarrow K^{*0} \mu^+ \mu^-$, the LEP and LHC searches for sleptons and $Z'$ boson, as well as the perturbative requirement. The viable parameter regions of the model are identified. In the presence of the gauge kinetic mixing term, those regions are enlarged and significantly deformed in comparison to the case with vanishing kinetic mixing. In the near future, the E989 experiment with the projected sensitivity will be able to test significant parts of the currently allowed parameter regions.Comment: 36 pages, 23 figures. Version to be published in Physical Review

THE WORK-OUTS TO OPTIMIZE THE EFFICIENCY FOOTWORK – A CASE STUDY FOR TALENTED FEMALE TABLE TENNIS ATHLETES AT THE AGE OF 14-15 IN VINH LONG PROVINCE, VIETNAM

The purpose of this study was to build up and evaluate the application of work-outs about the efficiency of footwork for talented female table tennis athletes. 08 healthy female talented table tennis athletes at the age of 14-15 in Vinh Long province were chosen to participate in the 8-week pre-season training. Results indicated that the 20 work-outs were selected to improve the efficiency footwork through the basis of training principle, participant’ characteristics, previous studies, and expert interviews. Besides, there were significant differences in all 06 tests to evaluate the footwork ability after the experiment. Moreover, the percentage of change indicated increased, from the objective perspective, we found that the growth rate was still at the moderate level (from 2.72% to 6.07%). Therefore, it is necessary to apply the 20 work-outs more flexibly and closely to improve the efficiency of footwork in different training phases next year. It was concluded that the application of the 20 work-outs about the efficiency of footwork had positive effects on female talented table tennis athletes. Future studies should be conducted on a group of males, diverse in training levels, and/or on the other sports group that need to promote footwork ability.   Article visualizations

APPLICATION OF GOOGLE EARTH SOFTWARE FOR TEACHING STUDENTS OF GEOGRAPHY EDUCATION AT AN GIANG UNIVERSITY, VIETNAM IN THE DIRECTION OF CAPACITY DEVELOPMENT

Applying information technology to teach students majoring in Geography pedagogy in a university environment in the direction of capacity development has contributed to improving training efficiency and quality. By analyzing and synthesizing documents combined with pedagogical experiments in the classroom, the article introduces Google Earth and the application of Google Earth to teach some geography modules for students of geography pedagogy at the An Giang University, Ho Chi Minh City National University, in the direction of capacity development. Through lessons and tests, assessments help students improve their general and specific competencies in Geography. In addition, the article also proposes some recommendations to allow lecturers to use Google Earth to teach Geography at universities more effectively.  Article visualizations

Improved Sensor Fault-Tolerant Control Technique Applied to Three-Phase Induction Motor Drive

An improved fault-tolerant control (FTC) method using mathematical functions is applied to the induction motor drive (IMD) against current sensors and speed encoder failures, which occur when the sensor is disconnected or completely damaged. The IMD with two current sensors and an encoder is speed controlled based on the field-oriented control (FOC) technique in regular operation. In this paper, an FTC unit is implemented in the FOC controller to detect and solve the sensor fault to increase the reliability of the speed control process. The measured stator currents and the feedback speed signal are integrated into the diagnosis algorithms to create a sensor fault-tolerant control function. Three diagnosis functions operating in a defined sequence are proposed for determining the health status of current and speed sensors. The FTC function performs isolation and replaces the faulty sensor signals with the proper estimated signals; then, the IMD will operate in the corresponding sensorless mode. Simulations will be performed to verify the accuracy and reliability of the proposed method under various sensor faults

New H∞ control design for polytopic systems with mixed time-varying delays in state and input

This paper concerns with the problem of state-feedback H∞ control design for a class of linear systems with polytopic uncertainties and mixed time-varying delays in state and input. Our approach can be described as follows. We first construct a state-feedback controller based on the idea of parameter-dependent controller design. By constructing a new parameter-dependent Lyapunov-Krasovskii functional (LKF), we then derive new delay-dependent conditions in terms of linear matrix inequalities ensuring the exponential stability of the corresponding closed-loop system with a H∞ disturbance attenuation level. The effectiveness and applicability of the obtained results are demonstrated by practical examples

On a Standard Model Extension with Vector-like Fermions and Abelian Symmetry

We investigate an extension of the standard model with vector-like fermions and an extra Abelian gauge symmetry. The particle mass spectrum is calculated explicitly. The Lagrangian terms for all the gauge interactions of leptons and quarks in the model are derived. We observe that while there is no new mixing in the lepton sector, the quark mixing plays an important role in the magnitudes of gauge interactions for quarks, particularly the interactions with massive $W$, $Z$ and $Z'$ bosons. We calculate the contributions of the new vector-like leptons and quarks to the Peskin-Takeuchi parameters as well as the $\rho$ parameter of the electroweak precision tests, and show that the model is realistic

Impact of sea level rise on current and wave in Van Uc coastal area

This paper presents the results of analysis, comparison of some characteristics of current, wave at Van Uc estuary area when being affected by sea level rise due to climate change based on Delft3D model. Scenario groups are established: The current scenario and the scenarios simulating effect of sea level rise 0.5 m and 1.0 m. The results of calculation and simulation show that the velocity values change locally when sea level rises: Rise in the northern and southern areas (0.2–5 cm/s); decrease in the navigation channel (0.6–30 cm/s). Sea level rise causes the increase of wave height in the coastal area (13.5–43.8% in the dry season and 20–40% in the rainy season) and fewer changes in the outer area