In the current paper,we present a study of the spatial distribution of luminous blue variables(LBVs)and various LBV candidates(c LBVs)with respect to OB associations in the galaxy M33.The identification of blue star g...In the current paper,we present a study of the spatial distribution of luminous blue variables(LBVs)and various LBV candidates(c LBVs)with respect to OB associations in the galaxy M33.The identification of blue star groups was based on the LGGS data and was carried out by two clustering algorithms with initial parameters determined during simulations of random stellar fields.We have found that the distribution of distances to the nearest OB association obtained for the LBV/c LBV sample is close to that for massive stars with Minit>20 M⊙and WolfRayet stars.This result is in good agreement with the standard assumption that LBVs represent an intermediate stage in the evolution of the most massive stars.However,some objects from the LBV/cLBV sample,particularly Fe II-emission stars,demonstrated severe isolation compared to other massive stars,which,together with certain features of their spectra,implicitly indicates that the nature of these objects and other LBVs/cLBVs may differ radically.展开更多
To assess the effectiveness of vaccination in contaminated environments,this study introduces a modeling framework that encompasses two transmission routes,namely direct human-to-human contact and indirect human-to-en...To assess the effectiveness of vaccination in contaminated environments,this study introduces a modeling framework that encompasses two transmission routes,namely direct human-to-human contact and indirect human-to-environment contact,as well as the implementation of new M72/AS01_(E)vaccine.Motivated by this,a coupled age-structured tuberculosis(TB)model is proposed.Its well-posedness requirement is verified using the integrated semigroup theory.Furthermore,this study presents a comprehensive analysis of threshold dynamics associated with the proposed model.Specifically,the global stability of the disease-free and positive steady states is demonstrated by employing Lyapunov functionals.Lastly,the effects of the vaccination with M72/AS01_(E)and contaminated environments on TB control are numerically simulated.Experimental results indicate that high concentrations of Mycobacterium tuberculosis in contaminated environments may somewhat impede TB control efforts,but that large-scale deployment of new vaccine could significantly reduce the prevalence of TB.展开更多
The construction method of background value is improved in the original multi-variable grey model （MGM（1,m）） from its source of construction errors. The MGM（1,m） with optimized background value is used to elimin...The construction method of background value is improved in the original multi-variable grey model （MGM（1,m）） from its source of construction errors. The MGM（1,m） with optimized background value is used to eliminate the random fluctuations or errors of the observational data of all variables, and the combined prediction model together with the multiple linear regression is established in order to improve the simulation and prediction accuracy of the combined model. Finally, a combined model of the MGM（1,2） with optimized background value and the binary linear regression is constructed by an example. The results show that the model has good effects for simulation and prediction.展开更多
In this article, the author establishes the strong laws for linear statistics that are weighted sums of a m-negatively associated(m-NA) random sample. The obtained results extend and improve the result of Qiu and Yang...In this article, the author establishes the strong laws for linear statistics that are weighted sums of a m-negatively associated(m-NA) random sample. The obtained results extend and improve the result of Qiu and Yang in [1] to m-NA random variables.展开更多
In this paper, by the three series theorem of m-negatively associated(m-NA,in short) random variables and the truncation method of random variables, we mainly investigated the strong convergence properties for partial...In this paper, by the three series theorem of m-negatively associated(m-NA,in short) random variables and the truncation method of random variables, we mainly investigated the strong convergence properties for partial sums of m-NA random variables.In addition, the Khintchine-Kolmogorov convergence theorem and Kolmogorov-type strong law of large numbers for m-NA random variables are also obtained. The results obtained in the paper generalize some corresponding ones for independent random variables and some dependent random variables.展开更多
The Mobile Commerce (m-commerce) becomes very powerful tool in the competitive business markets. Companies started to use this technology to attract their customers and catch their attention. Usage of Mobile commerce ...The Mobile Commerce (m-commerce) becomes very powerful tool in the competitive business markets. Companies started to use this technology to attract their customers and catch their attention. Usage of Mobile commerce applications spreaded around different countries and became very popular. Different communication protocols and security techniques are designed for business use of m-commerce. Mobile Commerce, likewise the e-commerce brought significant difference in the market. People start to use this technology by feeling the freedom of having transactions at anywhere and anytime. However, consumers face lot of difficulties while using this technology which is consumer-based or service provider based. This research exposes the impact of determinants that influences mobile commerce application users’ attitudes by classifying and investigating the internal and external variables in a case study of Cyprus Research Centre.展开更多
Improving mechanical quality factor Q_(m) is of great significance for high-power applications.Here,a new strategy of the[111]_(c) texture engineering was proposed to enhance the performances of high-power piezoelectr...Improving mechanical quality factor Q_(m) is of great significance for high-power applications.Here,a new strategy of the[111]_(c) texture engineering was proposed to enhance the performances of high-power piezoelectric ceramics.The 5 vol%BaTiO_(3)(BT)templates with the[111]c preferred orientation were in-troduced into matrix powders of 0.03 Pb(Mn_(1/3) Nb_(2/3))O_(3)-0.33Pb(Ni_(1/3) Nb_(2/3))O_(3)-0.28 PbZrO_(3)-0.36PbTiO_(3)(28PZ(R))to form the[111]c textured ceramics(28PZ(T)),possessing a texture degree of 74%.The mul-tiple of uniform density in EBSD increased from 0.63 in randomly oriented 28 PZ(R)to 6.63 in 28PZ(T).The good lattice matching between BT templates and textured grains was observed using high-resolution transmission electron microscopy,confirming the microscopic origin of the[111]c texture.The maximum phase angleθmax of 88.2°was quite near 90°in 28PZ(T),ensuring the optimal Qm value of 1275 and the great figure of merit of 255,000 pC/N.The increased Q_(m) in[111]c texture ceramics was confirmed due to the reduced intrinsic polarization directions rather than the pinning effect of the internal bias field.Larger grain sizes with larger domains restrained the movement of domain walls in 28 PZ(T),which was also favorable to higher Q_(m).This work may provide a new promising route for further high-power applications.展开更多
In this paper, Wittmann type strong laws of large numbers for blockwise mnegatively associated random variables are established which extend and improve the related known works in the literature.
文摘In the current paper,we present a study of the spatial distribution of luminous blue variables(LBVs)and various LBV candidates(c LBVs)with respect to OB associations in the galaxy M33.The identification of blue star groups was based on the LGGS data and was carried out by two clustering algorithms with initial parameters determined during simulations of random stellar fields.We have found that the distribution of distances to the nearest OB association obtained for the LBV/c LBV sample is close to that for massive stars with Minit>20 M⊙and WolfRayet stars.This result is in good agreement with the standard assumption that LBVs represent an intermediate stage in the evolution of the most massive stars.However,some objects from the LBV/cLBV sample,particularly Fe II-emission stars,demonstrated severe isolation compared to other massive stars,which,together with certain features of their spectra,implicitly indicates that the nature of these objects and other LBVs/cLBVs may differ radically.
文摘To assess the effectiveness of vaccination in contaminated environments,this study introduces a modeling framework that encompasses two transmission routes,namely direct human-to-human contact and indirect human-to-environment contact,as well as the implementation of new M72/AS01_(E)vaccine.Motivated by this,a coupled age-structured tuberculosis(TB)model is proposed.Its well-posedness requirement is verified using the integrated semigroup theory.Furthermore,this study presents a comprehensive analysis of threshold dynamics associated with the proposed model.Specifically,the global stability of the disease-free and positive steady states is demonstrated by employing Lyapunov functionals.Lastly,the effects of the vaccination with M72/AS01_(E)and contaminated environments on TB control are numerically simulated.Experimental results indicate that high concentrations of Mycobacterium tuberculosis in contaminated environments may somewhat impede TB control efforts,but that large-scale deployment of new vaccine could significantly reduce the prevalence of TB.
基金supported by the National Natural Science Foundation of China(71071077)the Ministry of Education Key Project of National Educational Science Planning(DFA090215)+1 种基金China Postdoctoral Science Foundation(20100481137)Funding of Jiangsu Innovation Program for Graduate Education(CXZZ11-0226)
文摘The construction method of background value is improved in the original multi-variable grey model （MGM（1,m）） from its source of construction errors. The MGM（1,m） with optimized background value is used to eliminate the random fluctuations or errors of the observational data of all variables, and the combined prediction model together with the multiple linear regression is established in order to improve the simulation and prediction accuracy of the combined model. Finally, a combined model of the MGM（1,2） with optimized background value and the binary linear regression is constructed by an example. The results show that the model has good effects for simulation and prediction.
基金Foundation item： Supported by the Humanities and Social Sciences Foundation for the Youth Scholars of Ministry of Education of China（12YJCZH217） Supported by the Natural Science Foundation of Anhui Province（1308085MA03） Supported by the Key Natural Science Foundation of Educational Committe of Anhui Province（KJ2014A255）
文摘In this article, the author establishes the strong laws for linear statistics that are weighted sums of a m-negatively associated(m-NA) random sample. The obtained results extend and improve the result of Qiu and Yang in [1] to m-NA random variables.
基金Supported by the Natural Science Foundation of Anhui Province（1508085J06） the Key Projects for Academic Talent of Anhui Province（gxbj ZD2016005） the Students Innovative Training Project of Anhui University（201610357001）
文摘In this paper, by the three series theorem of m-negatively associated(m-NA,in short) random variables and the truncation method of random variables, we mainly investigated the strong convergence properties for partial sums of m-NA random variables.In addition, the Khintchine-Kolmogorov convergence theorem and Kolmogorov-type strong law of large numbers for m-NA random variables are also obtained. The results obtained in the paper generalize some corresponding ones for independent random variables and some dependent random variables.
文摘The Mobile Commerce (m-commerce) becomes very powerful tool in the competitive business markets. Companies started to use this technology to attract their customers and catch their attention. Usage of Mobile commerce applications spreaded around different countries and became very popular. Different communication protocols and security techniques are designed for business use of m-commerce. Mobile Commerce, likewise the e-commerce brought significant difference in the market. People start to use this technology by feeling the freedom of having transactions at anywhere and anytime. However, consumers face lot of difficulties while using this technology which is consumer-based or service provider based. This research exposes the impact of determinants that influences mobile commerce application users’ attitudes by classifying and investigating the internal and external variables in a case study of Cyprus Research Centre.
基金supported by the Natural Science Foundation of Heilongjiang Province(No.LH2021E052)the National Natural Science Foundation of China(Grant Nos.52202131 and 52002093)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.HIT.NSRIF202313 and HIT.NSRIF202214)the National Key Research and Development Program of China(No.2022YFB3403902).
文摘Improving mechanical quality factor Q_(m) is of great significance for high-power applications.Here,a new strategy of the[111]_(c) texture engineering was proposed to enhance the performances of high-power piezoelectric ceramics.The 5 vol%BaTiO_(3)(BT)templates with the[111]c preferred orientation were in-troduced into matrix powders of 0.03 Pb(Mn_(1/3) Nb_(2/3))O_(3)-0.33Pb(Ni_(1/3) Nb_(2/3))O_(3)-0.28 PbZrO_(3)-0.36PbTiO_(3)(28PZ(R))to form the[111]c textured ceramics(28PZ(T)),possessing a texture degree of 74%.The mul-tiple of uniform density in EBSD increased from 0.63 in randomly oriented 28 PZ(R)to 6.63 in 28PZ(T).The good lattice matching between BT templates and textured grains was observed using high-resolution transmission electron microscopy,confirming the microscopic origin of the[111]c texture.The maximum phase angleθmax of 88.2°was quite near 90°in 28PZ(T),ensuring the optimal Qm value of 1275 and the great figure of merit of 255,000 pC/N.The increased Q_(m) in[111]c texture ceramics was confirmed due to the reduced intrinsic polarization directions rather than the pinning effect of the internal bias field.Larger grain sizes with larger domains restrained the movement of domain walls in 28 PZ(T),which was also favorable to higher Q_(m).This work may provide a new promising route for further high-power applications.
基金Supported by the National Natural Science Foundation of China(Grant No.11271161)
文摘In this paper, Wittmann type strong laws of large numbers for blockwise mnegatively associated random variables are established which extend and improve the related known works in the literature.
