Cylindrical vector beams(CVBs)hold significant promise in mode division multiplexing communication owing to their inherent vector mode orthogonality.However,existing studies for facilitating CVB channel processing are...Cylindrical vector beams(CVBs)hold significant promise in mode division multiplexing communication owing to their inherent vector mode orthogonality.However,existing studies for facilitating CVB channel processing are confined to mode shift conversions due to their reliance on spin-dependent helical modulations,overlooking the pursuit of mode multiplication conversion.This challenge lies in the multiplicative operation upon inhomogeneous vector mode manipulation,which is expected to advance versatile CVB channel switching and routing.Here,we tackle this gap by introducing a raytracing control strategy that conformally maps the light rays of CVB from the whole annulus distribution to an annular sector counterpart.Incorporated with the multifold conformal annulus-sector mappings and polarization-insensitive phase modulations,this approach facilitates the parallel transformation of input CVB into multiple complementary components,enabling the mode multiplication conversion with protected vector structure.Serving as a demonstration,we experimentally implemented the multiplicative operation of four CVB modes with the multiplier factors of N=+2 and N=−3,achieving the converted mode purities over 94.24%and 88.37%.Subsequently,200 Gbit/s quadrature phase shift keying signals were successfully transmitted upon multiplicative switching of four CVB channels,with the bit-error-rate approaching 1×10^(−6).These results underscore our strategy’s efficacy in CVB mode multiplication,which may open promising prospects for its advanced applications.展开更多
This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularl...This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularly multiplication and division. The operations of multiplication and division are represented by algebraic formulas. An advantage of the method is that the cumulative process can be performed on decimal numbers. The present paper aims to establish a basic and useful formula valid for the two fundamental arithmetic operations of multiplication and division. The new cumulative method proved to be more flexible and made it possible to extend the multiplication and division based on repeated addition/subtraction to decimal numbers.展开更多
Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4))...Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness.展开更多
Toeplitz matrix-vector multiplication is widely used in various fields,including optimal control,systolic finite field multipliers,multidimensional convolution,etc.In this paper,we first present a non-asymptotic quant...Toeplitz matrix-vector multiplication is widely used in various fields,including optimal control,systolic finite field multipliers,multidimensional convolution,etc.In this paper,we first present a non-asymptotic quantum algorithm for Toeplitz matrix-vector multiplication with time complexity O(κpolylogn),whereκand 2n are the condition number and the dimension of the circulant matrix extended from the Toeplitz matrix,respectively.For the case with an unknown generating function,we also give a corresponding non-asymptotic quantum version that eliminates the dependency on the L_(1)-normρof the displacement of the structured matrices.Due to the good use of the special properties of Toeplitz matrices,the proposed quantum algorithms are sufficiently accurate and efficient compared to the existing quantum algorithms under certain circumstances.展开更多
目的通过Meta分析确定中国老年慢性病共病的患病率和危险因素,为制定适合我国实际情况的老年人慢性病共病健康管理策略和社区干预方案提供科学依据。方法系统检索PubMed、Embase、Web of Science、Cochrane、中国期刊全文数据库(CNKI)...目的通过Meta分析确定中国老年慢性病共病的患病率和危险因素,为制定适合我国实际情况的老年人慢性病共病健康管理策略和社区干预方案提供科学依据。方法系统检索PubMed、Embase、Web of Science、Cochrane、中国期刊全文数据库(CNKI)、中国科技期刊全文数据库(VIP)、万方数据库以及中国生物医药文献数据库(CBM)等关于中国老年慢性病共病的患病率和危险因素的观察性研究。两名具有循证护理学习经验的研究者通过三轮筛选、文献评价、数据提取,采用Stata20.0软件对中国老年慢性病共病的患病率和危险因素依次进行Meta合并、敏感性分析和发表偏倚分析。结果中英文数据初检出相关文献2727篇,最终纳入14篇文献,总样本量54982例,提取影响因素14个。Meta分析结果显示,中国老年人慢性病共病患病率为44.9%,95%CI:34.1%~55.7%。中国老年人慢性病共病危险因素包括:年龄(≥70岁)、性别(女)、慢性病家族史、婚姻状况(单身、丧偶、离异)、BMI(≥24 kg/m^(2))、吸烟、饮酒,OR值和95%CI分别是1.40(1.28~1.53)、1.22(1.10~1.34)、2.15(1.87~2.46)、1.40(1.17~1.68)、1.59(1.03~2.43)、1.18(1.08~1.30)、1.20(1.02~1.42)。结论中国老年慢性病共病的患病率较高,其中年龄(≥70岁)、性别(女)、慢性病家族史、婚姻状况(单身、丧偶、离异)、BMI(≥24 kg/m^(2))、吸烟、饮酒是中国老年慢性病共病的危险因素。针对可改变的危险因素,未来应积极改善老年人不健康的生活方式,开展综合性的干预措施。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.62271322)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515030152)+1 种基金the Shenzhen Science and Technology Program(Grant No.JCYJ20210324095610027)the Natural Science Foundation of Top Talent of SZTU(Grant No.GDRC202204)。
文摘Cylindrical vector beams(CVBs)hold significant promise in mode division multiplexing communication owing to their inherent vector mode orthogonality.However,existing studies for facilitating CVB channel processing are confined to mode shift conversions due to their reliance on spin-dependent helical modulations,overlooking the pursuit of mode multiplication conversion.This challenge lies in the multiplicative operation upon inhomogeneous vector mode manipulation,which is expected to advance versatile CVB channel switching and routing.Here,we tackle this gap by introducing a raytracing control strategy that conformally maps the light rays of CVB from the whole annulus distribution to an annular sector counterpart.Incorporated with the multifold conformal annulus-sector mappings and polarization-insensitive phase modulations,this approach facilitates the parallel transformation of input CVB into multiple complementary components,enabling the mode multiplication conversion with protected vector structure.Serving as a demonstration,we experimentally implemented the multiplicative operation of four CVB modes with the multiplier factors of N=+2 and N=−3,achieving the converted mode purities over 94.24%and 88.37%.Subsequently,200 Gbit/s quadrature phase shift keying signals were successfully transmitted upon multiplicative switching of four CVB channels,with the bit-error-rate approaching 1×10^(−6).These results underscore our strategy’s efficacy in CVB mode multiplication,which may open promising prospects for its advanced applications.
文摘This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularly multiplication and division. The operations of multiplication and division are represented by algebraic formulas. An advantage of the method is that the cumulative process can be performed on decimal numbers. The present paper aims to establish a basic and useful formula valid for the two fundamental arithmetic operations of multiplication and division. The new cumulative method proved to be more flexible and made it possible to extend the multiplication and division based on repeated addition/subtraction to decimal numbers.
文摘Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness.
基金supported by the National Natural Science Foundation of China(Grant Nos.62071015 and 62171264)。
文摘Toeplitz matrix-vector multiplication is widely used in various fields,including optimal control,systolic finite field multipliers,multidimensional convolution,etc.In this paper,we first present a non-asymptotic quantum algorithm for Toeplitz matrix-vector multiplication with time complexity O(κpolylogn),whereκand 2n are the condition number and the dimension of the circulant matrix extended from the Toeplitz matrix,respectively.For the case with an unknown generating function,we also give a corresponding non-asymptotic quantum version that eliminates the dependency on the L_(1)-normρof the displacement of the structured matrices.Due to the good use of the special properties of Toeplitz matrices,the proposed quantum algorithms are sufficiently accurate and efficient compared to the existing quantum algorithms under certain circumstances.
文摘目的通过Meta分析确定中国老年慢性病共病的患病率和危险因素,为制定适合我国实际情况的老年人慢性病共病健康管理策略和社区干预方案提供科学依据。方法系统检索PubMed、Embase、Web of Science、Cochrane、中国期刊全文数据库(CNKI)、中国科技期刊全文数据库(VIP)、万方数据库以及中国生物医药文献数据库(CBM)等关于中国老年慢性病共病的患病率和危险因素的观察性研究。两名具有循证护理学习经验的研究者通过三轮筛选、文献评价、数据提取,采用Stata20.0软件对中国老年慢性病共病的患病率和危险因素依次进行Meta合并、敏感性分析和发表偏倚分析。结果中英文数据初检出相关文献2727篇,最终纳入14篇文献,总样本量54982例,提取影响因素14个。Meta分析结果显示,中国老年人慢性病共病患病率为44.9%,95%CI:34.1%~55.7%。中国老年人慢性病共病危险因素包括:年龄(≥70岁)、性别(女)、慢性病家族史、婚姻状况(单身、丧偶、离异)、BMI(≥24 kg/m^(2))、吸烟、饮酒,OR值和95%CI分别是1.40(1.28~1.53)、1.22(1.10~1.34)、2.15(1.87~2.46)、1.40(1.17~1.68)、1.59(1.03~2.43)、1.18(1.08~1.30)、1.20(1.02~1.42)。结论中国老年慢性病共病的患病率较高,其中年龄(≥70岁)、性别(女)、慢性病家族史、婚姻状况(单身、丧偶、离异)、BMI(≥24 kg/m^(2))、吸烟、饮酒是中国老年慢性病共病的危险因素。针对可改变的危险因素,未来应积极改善老年人不健康的生活方式,开展综合性的干预措施。
