An Adaptive Momentum CMA Blind Equalization Based on Error Energy

To solve the problem of large steady state residual error of momentum constant modulus algorithm (CMA) blind equalization, a momentum CMA blind equalization controlled by energy steady state was proposed. The energy of the equalizer weights is estimated during the updating process. According to the adaptive filtering theory, the energy of the equalizer weights reaches to the steady state after the algorithm is converged, and then the momentum can be set to 0 when the energy change rate is less than the threshold, which can avoid the additional gradient noise caused by momentum and further improve the convergence precision of the algorithm. The proposed algorithm takes advantage of momentum to quicken the convergence rate and to avoid the local minimum in the cost function to some extent;meanwhile, it has the same convergence precision with CMA. Computer simulation results show that, compared with CMA, momentum CMA (MCMA) and adaptive momentum CMA (AMCMA) blind equalization, the proposed algorithm has the fastest convergence rate and the same steady state residual error with CMA.

Band-gap tunable(Ga_(x)In_(1−x))_(2)O_(3)layer grown by magnetron sputtering

Multicomponent oxide(Ga_(x)In_(1−x))_(2)O_(3)films are prepared on(0001)sapphire substrates to realize a tunable band-gap by magnetron sputtering technology followed by thermal annealing.The optical properties and band structure evolution over the whole range of compositions in ternary compounds(Ga_(x)In_(1−x))_(2)O_(3)are investigated in detail.The X-ray diffraction spectra clearly indicate that(Ga_(x)In_(1−x))_(2)O_(3)films with Ga content varying from 0.11 to 0.55 have both cubic and monoclinic structures,and that for films with Ga content higher than 0.74,only the monoclinic structure appears.The transmittance of all films is greater than 86%in the visible range with sharp absorption edges and clear fringes.In addition,a blue shift of ultraviolet absorption edges from 380 to 250 nm is noted with increasing Ga content,indicating increasing band-gap energy from 3.61 to 4.64 eV.The experimental results lay a foundation for the application of transparent conductive compound(Ga_(x)In_(1−x))_(2)O_(3)thin films in photoelectric and photovoltaic industry,especially in display,light-emitting diode,and solar cell applications.

Normal-Weight Abdominal Obesity: A Risk Factor for Hypertension and Cardiometabolic Dysregulation

Objective:This study aimed to examine the associations of waist circumference with hypertension and cardiometabolic dysregulation among normal-weight adults.Methods:This cross-sectional study included 8795 normal-weight participants aged 20 to 79 years from the 2009–2018 US National Health and Nutrition Examination Survey.The demographic characteristics and cardiometabolic risk factors across waist circumference quartiles were summarized.We used adjusted multivariate logistic regression models,subgroup analysis,and restricted cubic spline to analyze the association between waist circumference and the prevalence of hypertension.Thereafter,we used the random forest supervised machine learning method,together with least absolute shrinkage and selection operator regression,to select hypertension-related features and created a predictive model based on regression analysis to identify hypertension in normal-weight individuals.Results:Waist circumference was positively correlated with hypertension in the non-adjusted,minimally adjusted,and fully adjusted models,with odds ratios(95%confidence interval)of 2.28(2.14–2.44),1.27(1.12–1.44),and 1.27(1.12–1.44),respectively.In the fully adjusted model,participants in the highest waist circumference quartile had a higher risk of hypertension relative to those in the lowest quartile,with an odds ratio(95%confidence interval)of 3.87(1.59–10.34).Sensitivity analysis demonstrated the robustness of the association.In the testing set,the predictive model exhibited good performance,with an area under the curve of 0.803,sensitivity of 0.72,specificity of 0.76,and negative predictive value of 0.84.Conclusions:Measuring waist circumference may improve the evaluation of the risk of hypertension and help to manage cardiometabolic risk in normal-weight individuals.