In this paper, the problem of estimating the covariance matrix in general linear mixed models is considered. A new class of estimators is proposed. It is shown that this new estimator dominates the analysis of varianc...In this paper, the problem of estimating the covariance matrix in general linear mixed models is considered. A new class of estimators is proposed. It is shown that this new estimator dominates the analysis of variance estimate under two squared loss functions. Finally, some simulation results to compare the performance of the proposed estimator with that of the analysis of variance estimate are reported. The simulation results indicate that this new estimator provides a substantial improvement in risk under most situations.展开更多
AMD:年龄相关性黄斑变性(age-related macular degeneration)ANOVA:方差分析(analysis of variance)BUT:泪膜破裂时间(breakup time of tear film)DR:糖尿病视网膜病变(diabetic retinopathy)EAU:实验性自身免疫性葡萄膜炎(experimental...AMD:年龄相关性黄斑变性(age-related macular degeneration)ANOVA:方差分析(analysis of variance)BUT:泪膜破裂时间(breakup time of tear film)DR:糖尿病视网膜病变(diabetic retinopathy)EAU:实验性自身免疫性葡萄膜炎(experimental autoimmune uveitis)。展开更多
Wire⁃Electrical Discharge Machining(WEDM)process can create any complex contour in any conducting material,regardless of its strength or hardness,with higher accuracy.Present experimental investigation aims to determi...Wire⁃Electrical Discharge Machining(WEDM)process can create any complex contour in any conducting material,regardless of its strength or hardness,with higher accuracy.Present experimental investigation aims to determine suitable input process/machining parameters,e.g.pulse on time(TON),peak current(IP),wire feed rate(WF),and pulse off time(TOFF),for optimizing the process performances,namely,cutting rate,kerf width,average roughness value of the machined surface,micro hardness,and surface crack density.Since four input parameters are considered in the present investigation,and each parameter is assumed to vary at three different levels(i.e.low,medium,high),the Taguchi L9 Orthogonal Array(OA)design approach has been used for the experimental purpose to enhance the process effiency.Similarly,a simple and popular multiresponse optimization approach,namely Grey Relational Analysis(GRA),is used to optimize five performance characteristics(output responses)simultaneously.The optimum process variables obtained are:TON of 110μs,TOFF of 40μs,IP of 10 A,and WF of 6 mm/min.These optimum process variables are validated with confirmatory experiment.The relative impact of input variables is determined using the Analysis of Variance(ANOVA)technique.Finally,correlations between individual outputs with different input parameters are established.This work will be helpful for industry personnel to use this machining process in a techno⁃economic way.展开更多
This study examines how demographic factors shape engagement with virtual cultural communities and awareness of emerging economic models.Using survey data from 202 participants,descriptive statistics,independent sampl...This study examines how demographic factors shape engagement with virtual cultural communities and awareness of emerging economic models.Using survey data from 202 participants,descriptive statistics,independent samples t-tests,and One-way Analysis of Variance(ANOVA)with Least Significant Difference(LSD)post-hoc analyses revealed significant influences of age,education,and occupation.No significant gender differences were found.Individuals aged 26-45 demonstrated higher virtual community participation(F=3.439,p=0.01)and emerging model awareness(F=2.834,p=0.026)than younger cohorts(18-25 years and below).Respondents with postgraduate education exhibited superior understanding of emerging economic models(F=3.296,p=0.022)and their nexus with cultural values(F=6.196,p<0.001)compared to those with lower educational attainment.Significant occupational variations existed in virtual participation(F=4.001,p=0.008)and economic model awareness(F=5.611,p=0.001),with enterprise employees and civil servants scoring higher than students and freelancers.These findings underscore the critical roles of life stage,educational investment,and professional context in shaping digital cultural behaviors and economic cognition,offering valuable insights for platform design,educational strategies,and policy development in the digital cultural economy.展开更多
This study investigates the effect of apple extract on CoFe_(2)O_(4) nanoparticles synthesized via a green self-ignition method.High resolution transmission electron microscope(HRTEM)showed nanometric particles with v...This study investigates the effect of apple extract on CoFe_(2)O_(4) nanoparticles synthesized via a green self-ignition method.High resolution transmission electron microscope(HRTEM)showed nanometric particles with varied shapes,while X-ray diffraction(XRD)and Rietveld refinement confirmed a facecentered cubic(Fd3m)structure.Mössbauer spectroscopy revealed a Zeeman sextet pattern with only Fe^(3+) ions.Ultra violet vissible nearinfrared(UV-Vis-NIR)spectra indicated strong absorbance in the visible and NIR regions,suggesting optoelectronic potential.The nanoparticles demonstrated high photo-Fenton catalytic efficiency,degrading 96.88%of Methylene Blue under visible light.They also exhibited 100%adsorption capacities for Cr^(3+) and Pb^(2+),making them effective for water treatment.These properties were attributed to a large surface area(347.04 m2/g),mesoporous structure,and mixed spinel phase.ANOVA and Tukey’s honestly significant difference(HSD)tests confirmed that contact time and adsorbent dosage significantly affected pollutant removal.Additionally,strong antimicrobial activity highlighted their biotechnological relevance.The inclusion of apple extract enhanced structural and functional features,expanding application prospects in spin valves,magnetic recording,refrigeration,microwave technologies(C to Ku bands),optoelectronics,and biotechnology.Future work should explore the photo-Fenton degradation mechanism and optimize synthesis for scalable production,aiming to maximize their industrial utility.展开更多
基金This research is supported by National Natural Science Foundation of China, Tian Yuan Special Foundation under Grant No. 10926059 and Zhejiang Provincial Natural Science Foundation of China under Grant No. Y6100053.
文摘In this paper, the problem of estimating the covariance matrix in general linear mixed models is considered. A new class of estimators is proposed. It is shown that this new estimator dominates the analysis of variance estimate under two squared loss functions. Finally, some simulation results to compare the performance of the proposed estimator with that of the analysis of variance estimate are reported. The simulation results indicate that this new estimator provides a substantial improvement in risk under most situations.
文摘AMD:年龄相关性黄斑变性(age-related macular degeneration)ANOVA:方差分析(analysis of variance)BUT:泪膜破裂时间(breakup time of tear film)DR:糖尿病视网膜病变(diabetic retinopathy)EAU:实验性自身免疫性葡萄膜炎(experimental autoimmune uveitis)。
文摘Wire⁃Electrical Discharge Machining(WEDM)process can create any complex contour in any conducting material,regardless of its strength or hardness,with higher accuracy.Present experimental investigation aims to determine suitable input process/machining parameters,e.g.pulse on time(TON),peak current(IP),wire feed rate(WF),and pulse off time(TOFF),for optimizing the process performances,namely,cutting rate,kerf width,average roughness value of the machined surface,micro hardness,and surface crack density.Since four input parameters are considered in the present investigation,and each parameter is assumed to vary at three different levels(i.e.low,medium,high),the Taguchi L9 Orthogonal Array(OA)design approach has been used for the experimental purpose to enhance the process effiency.Similarly,a simple and popular multiresponse optimization approach,namely Grey Relational Analysis(GRA),is used to optimize five performance characteristics(output responses)simultaneously.The optimum process variables obtained are:TON of 110μs,TOFF of 40μs,IP of 10 A,and WF of 6 mm/min.These optimum process variables are validated with confirmatory experiment.The relative impact of input variables is determined using the Analysis of Variance(ANOVA)technique.Finally,correlations between individual outputs with different input parameters are established.This work will be helpful for industry personnel to use this machining process in a techno⁃economic way.
文摘This study examines how demographic factors shape engagement with virtual cultural communities and awareness of emerging economic models.Using survey data from 202 participants,descriptive statistics,independent samples t-tests,and One-way Analysis of Variance(ANOVA)with Least Significant Difference(LSD)post-hoc analyses revealed significant influences of age,education,and occupation.No significant gender differences were found.Individuals aged 26-45 demonstrated higher virtual community participation(F=3.439,p=0.01)and emerging model awareness(F=2.834,p=0.026)than younger cohorts(18-25 years and below).Respondents with postgraduate education exhibited superior understanding of emerging economic models(F=3.296,p=0.022)and their nexus with cultural values(F=6.196,p<0.001)compared to those with lower educational attainment.Significant occupational variations existed in virtual participation(F=4.001,p=0.008)and economic model awareness(F=5.611,p=0.001),with enterprise employees and civil servants scoring higher than students and freelancers.These findings underscore the critical roles of life stage,educational investment,and professional context in shaping digital cultural behaviors and economic cognition,offering valuable insights for platform design,educational strategies,and policy development in the digital cultural economy.
文摘This study investigates the effect of apple extract on CoFe_(2)O_(4) nanoparticles synthesized via a green self-ignition method.High resolution transmission electron microscope(HRTEM)showed nanometric particles with varied shapes,while X-ray diffraction(XRD)and Rietveld refinement confirmed a facecentered cubic(Fd3m)structure.Mössbauer spectroscopy revealed a Zeeman sextet pattern with only Fe^(3+) ions.Ultra violet vissible nearinfrared(UV-Vis-NIR)spectra indicated strong absorbance in the visible and NIR regions,suggesting optoelectronic potential.The nanoparticles demonstrated high photo-Fenton catalytic efficiency,degrading 96.88%of Methylene Blue under visible light.They also exhibited 100%adsorption capacities for Cr^(3+) and Pb^(2+),making them effective for water treatment.These properties were attributed to a large surface area(347.04 m2/g),mesoporous structure,and mixed spinel phase.ANOVA and Tukey’s honestly significant difference(HSD)tests confirmed that contact time and adsorbent dosage significantly affected pollutant removal.Additionally,strong antimicrobial activity highlighted their biotechnological relevance.The inclusion of apple extract enhanced structural and functional features,expanding application prospects in spin valves,magnetic recording,refrigeration,microwave technologies(C to Ku bands),optoelectronics,and biotechnology.Future work should explore the photo-Fenton degradation mechanism and optimize synthesis for scalable production,aiming to maximize their industrial utility.
