Amplitude analysis and branching fraction measurement of the decay $$ {D}_s^{+} $$ → π+π0π0

Using a data set corresponding to an integrated luminosity of 6.32 fb−1 recorded by the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV, an amplitude analysis of the decay $$ {D}_s^{+} $$ D s + → π+π0π0 is performed, and the relative fractions and phases of different intermediate processes are determined. The absolute branching fraction of the decay $$ {D}_s^{+} $$ D s + → π+π0π0 is measured to be (0.50 ± 0.04stat ± 0.02syst)%. The absolute branching fraction of the intermediate process $$ {D}_s^{+} $$ D s + → f0(980)π+, f0(980) → π0π0 is determined to be (0.28 ± 0.04stat ± 0.04syst)%.

Comparison of core stabilization techniques on ultrasound imaging of the diaphragm, and core muscle thickness and external abdominal oblique muscle electromyography activity

BACKGROUND: To restore core stability, abdominal drawing-in maneuver (ADIM), abdominal bracing (AB), and dynamic neuromuscular stabilization (DNS) have been employed but outcome measures varied and one intervention was not superior over another. OBJECTIVE: The purpose of this study was to compare the differential effects of ADIM, AB, and DNS on diaphragm movement, abdominal muscle thickness difference, and external abdominal oblique (EO) electromyography (EMG) amplitude. METHODS: Forty-one participants with core instability participated in this study. The subjects performed ADIM, AB, and DNS in random order. A Simi Aktisys and Pressure Biofeedback Unit (PBU) were utilized to measure core stability, an ultrasound was utilized to measure diaphragm movement and measure abdominal muscles thickness and EMG was utilized to measure EO amplitude. Analysis of variance (ANOVA) was conducted at P< 0.05. RESULTS: Diaphragm descending movement and transverse abdominis (TrA) and internal abdominal oblique (IO) thickness differences were significantly increased in DNS compared to ADIM and AB (P< 0.05). EO amplitude was significantly increased in AB compared to ADIM, and DNS. CONCLUSIONS: DNS was the best technique to provide balanced co-activation of the diaphragm and TrA with relatively less contraction of EO and subsequently producing motor control for efficient core stabilization.

On the Possibility of Reducing the Measurement Error of Spectrometers with Proportional Gas Detectors in the RC-CR Formation of Output Signals

When analyzing the elemental composition of the substance under study, the task is to determine the true intensity of the radiation lines. The error in determining the intensity is caused by errors in the spectrometer. Reducing the error can be achieved by taking into account (correcting) the errors, as well as reducing them. In this paper, we propose a method for reducing the measurement error by reducing the miscalculations with an acceptable deterioration in the energy resolution of the spectrometer. An algorithm for automatically setting the duration of the output signals of the spectrometric amplifier and the width of the differential discriminator window for amplitude analysis is presented.

Introduction to this special section: Quantitative interpretation

Quantitative interpretation (QI) is the geophysicist's endeavor to go beyond reservoir architecture. It is the effort to use geophysical measurements in understanding reservoir properties such as rock type, porosity, and fluid composition. QI often refers to the use of seismic amplitude analysis to predict lithology, porosity, and pore fluids away from the wellbore in oil and gas reservoirs. However, we can generalize and expand the concept of QI beyond seismic methods and beyond oil and gas reservoirs. In this special section, we feature five papers and cover not only seismic and well-log data, but also gravity and magnetic data. We address a hydrothermal reservoir in addition to several oil and gas reservoirs.

Использование амплитудного анализа сигналов акустической эмиссии при циклическом и статическом нагружении стальных образцов

The results of amplitude analysis of discrete acoustic emission signals from developed sources such as fatigue cracks are presented. A combined loading of low-alloy and low-carbon steel samples with stress concentrators was carried out. The analysis of the probability density of the distribution of the registered AE signals from one source by amplitudes was made. A power-behaved dependence of the frequency of distribution of the amplitude of signals with a high correlation coefficient for AE sources has been established. The research data made it possible to develop a method for restoring the total number of acoustic emission acts from a source at a given sensitivity level.

Analysis Methods for Aerodynamic Instability Detection on a Multistage Axial Compressor

In order to detect the aerodynamic instability of a multistage axial compressor more accurately and earlier, the harmonic Fourier mean amplitude analysis method and heterotopic variance analysis method are developed. The dynamic instability prediction performance of the two methods is studied on a low-speed and a high-speed two-stage axial compressor. The harmonic Fourier mean amplitude analysis method is suitable for predicting the aerodynamic instability of a multistage axial compressor in the form of a rotating stall. Compared with the traditional harmonic Fourier analysis methods, the harmonic Fourier mean amplitude analysis method can capture the detail of the pressure signal more accurately and it can effectively prevent instability misjudgment. The heterotopic variance analysis method is developed based on the conventional variance analysis method, and it can be used to distinguish whether the compressor is in the rotating stall or the surge state. The heterotopic variance analysis method can predict the aerodynamic instability ahead of the harmonic Fourier mean amplitude analysis method, and fewer circumferential measuring points were employed. The layout of the measuring points also influences the detection of the aerodynamic instability of the compressor. The aerodynamic instability of the high-speed axial compressor can be predicted earlier by employing measuring points at the compressor outlet.