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基于非Fourier生物热传导解析解的激光辐照皮肤组织热损伤分析
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作者 张丽静 张齐 尚新春 《北京理工大学学报》 北大核心 2026年第2期192-201,共10页
较为准确地预测激光辐照下皮肤组织内部的热分布和热损伤是生物医学领域的一个难题.为探究这个问题,提出了一种使用Laplace和Hankel变换推导出解析解的策略.建立三维非Fourier热传导模型,并引入升温函数简化问题.通过积分变换及其逆变... 较为准确地预测激光辐照下皮肤组织内部的热分布和热损伤是生物医学领域的一个难题.为探究这个问题,提出了一种使用Laplace和Hankel变换推导出解析解的策略.建立三维非Fourier热传导模型,并引入升温函数简化问题.通过积分变换及其逆变换推导出解析解,并基于该解析解进行数值模拟,得到了不同辐照时间和半径下皮肤热分布和热损伤的预测结果,进而研究了激光辐照持续时间和半径对皮肤组织的影响.此外,对非Fourier热传导模型和经典Fourier热传导模型得到的皮肤组织热损伤预测结果进行了全面比较.分析结果表明,非Fourier和经典Fourier两种热传导模型所预测的热损伤深度是不同的.具体来讲,在短时间辐照时,非Fourier热传导理论的预测深度要小于Fourier热传导理论,而长时间辐照时,结果恰好相反. 展开更多
关键词 激光 生物材料 fourier效应 积分变换 解析解 热损伤
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基于Fourier近似Wasserstein距离的隐式全波形反演方法
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作者 陈星铨 黄兴国 +2 位作者 王乃建 雷云山 许银坡 《中国石油大学学报(自然科学版)》 北大核心 2026年第1期35-44,共10页
全波形反演作为一种高分辨率地下成像技术,在实际应用中仍面临低频数据缺失、周期跳跃以及噪声干扰等一系列挑战,因此提出一种基于Fourier近似Wasserstein距离的隐式全波形反演方法。在目标函数层面,利用Wasserstein距离与Fourier系数... 全波形反演作为一种高分辨率地下成像技术,在实际应用中仍面临低频数据缺失、周期跳跃以及噪声干扰等一系列挑战,因此提出一种基于Fourier近似Wasserstein距离的隐式全波形反演方法。在目标函数层面,利用Wasserstein距离与Fourier系数之间的有界关系,构建基于Fourier近似的低频增强型目标函数。通过对地震数据中低波数成分进行加权增强,提高模型背景速度的恢复质量,从而有效缓解周期跳跃问题。在模型重参数化层面,引入基于正弦激活函数的神经网络对速度模型进行隐式表征,利用其连续的高维映射特性替代传统的离散网格表示,在提高模型表征自由度的同时为反演过程引入由参数化带来的平滑约束。选取Marmousi、Marmousi2和SEG Salt 3个典型模型,分别在低频缺失、线性初始模型、含噪场景和强散射介质等条件下评估方法的有效性。结果表明,在初始模型较差、低频缺失、噪声干扰和强散射等复杂条件下,所提方法均表现出优异的鲁棒性与收敛性,能够有效克服周期跳跃并显著提升反演精度。 展开更多
关键词 地震成像 全波形反演 Wasserstein距离 模型重参数化 fourier变换 周期跳跃
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Hecke-Maass尖形式Fourier系数的变号问题
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作者 李赛 陈国华 《兰州文理学院学报(自然科学版)》 2026年第1期23-28,共6页
设f(z)是全模群SL(2,Ζ)上的Hecke-Maass尖形式,对应的Laplace特征值为λ=1/4+ν2,λ(n)(n≥1)是f(z)的标准化Fourier系数.本文利用复分析的方法,借助L-函数的亚凸界和均值估计结果、Perron公式和留数定理等工具,研究了两个整数平方和... 设f(z)是全模群SL(2,Ζ)上的Hecke-Maass尖形式,对应的Laplace特征值为λ=1/4+ν2,λ(n)(n≥1)是f(z)的标准化Fourier系数.本文利用复分析的方法,借助L-函数的亚凸界和均值估计结果、Perron公式和留数定理等工具,研究了两个整数平方和序列上Fourier系数{λ(n):n=c^(2)+d^(2),(c,d)∈Ζ^(2)}的变号问题,对于充分大的x,得到了序列{λ(n):n=c^(2)+d^(2),(c,d)∈Ζ^(2)}在区间(x,x+x^(δ)]上至少存在一次符号改变.当n≤x时,序列{λ(n):n=c^(2)+d^(2),(c,d)∈Ζ^(2)}变号次数的下界远大于x^(1-δ),其中,37/51<δ<1. 展开更多
关键词 Hecke-Maass形式 fourier系数 符号改变
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Plucking Heartstrings--Young musicians bring ancient instruments into the modern era
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作者 Li Xiaoyang 《Beijing Review》 2026年第3期38-39,共2页
Chinese video game Black Myth:Wukong has been a hit among gaming enthusiasts world-wide since its release in 2024,its breakout success demonstrating the potential global appeal of traditional Chinese culture.Based on ... Chinese video game Black Myth:Wukong has been a hit among gaming enthusiasts world-wide since its release in 2024,its breakout success demonstrating the potential global appeal of traditional Chinese culture.Based on 16th-century classic novel Journey to the West,the game is not only introducing international audiences to Chinese literature,but has also become a far-reaching platform for traditional Chinese music. 展开更多
关键词 Black Myth Wukong traditional Chinese culture traditional chinese music ancient instruments modern era plucking heartstrings global appeal Chinese video game
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杂波背景下目标回波信号积累预置MTI的递归Radon-Fourier变换方法
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作者 汪海波 巴涛 +3 位作者 黄文华 张余川 庄俊 张海川 《系统工程与电子技术》 北大核心 2025年第9期2913-2924,共12页
雷达系统的时序被分成固定的相参处理间隔(coherent processing interval, CPI),只有接收完整个CPI内的回波数据,才能应用Radon傅里叶变换(Radon-Fourier transform,RFT)方法实现相参积累,导致系统的处理延时至少是一个CPI的长度。对此... 雷达系统的时序被分成固定的相参处理间隔(coherent processing interval, CPI),只有接收完整个CPI内的回波数据,才能应用Radon傅里叶变换(Radon-Fourier transform,RFT)方法实现相参积累,导致系统的处理延时至少是一个CPI的长度。对此,提出一种预置运动目标显示(pre-moving target indication, Pre-MTI)的递归RFT方法,突破RFT方法需要一个整个CPI回波数据的限制。每接收一次回波数据即可实施相参积累,理论上系统处理延时最短到与雷达工作重复周期相当。本文对算法的相参积累增益、相参积累时间和改善因子进行理论分析,给出相应的解析推导。仿真结果表明,通过Pre-MTI处理能够有效抑制杂波,递归RFT变换方法能够对运动目标回波实现有效积累,信噪比和速度分辨率随着递归的脉冲个数增加而增加。通过递归RFT变换方法实线相参积累的系统延时降低,理论上最短延时可达雷达重复周期。 展开更多
关键词 时距联合 相参积累 运动目标显示 Radon傅里叶变换
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Riesz变换在Fourier-Besov空间中的有界性研究
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作者 孟虹宇 彭磊 《哈尔滨师范大学自然科学学报》 2025年第1期10-14,共5页
Riesz变换与Riesz位势在偏微分方程方面的应用广泛,可以有效的表示出方程的算子半群或是估计方程的基本解.探究Riesz变换和Riesz位势在Fourier-Besov空间内的有界性,并证明了Riesz变换和Riesz位势在Fourier-Besov空间的有界性,这为Fouri... Riesz变换与Riesz位势在偏微分方程方面的应用广泛,可以有效的表示出方程的算子半群或是估计方程的基本解.探究Riesz变换和Riesz位势在Fourier-Besov空间内的有界性,并证明了Riesz变换和Riesz位势在Fourier-Besov空间的有界性,这为Fourier-Besov空间的有界性研究提供了新思路. 展开更多
关键词 RIESZ变换 RIESZ位势 fourier-Besov空间 有界性
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Walsh-Kaczmarz-Fourier级数在Orlicz空间中的Norlund平均逼近
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作者 刘倩 吴嘎日迪 《应用数学》 北大核心 2025年第2期542-552,共11页
本文讨论Walsh-Kaczmarz-Fourier级数在Orlicz空间内的Norlund平均逼近问题,借助Orlicz空间内的Holder不等式、Minkowski不等式和连续模等工具,给出了Norlund平均逼近速度的两种估计.文中结果包含Lp空间内的同类结果.
关键词 fourier级数 Norlund平均 ORLICZ空间 连续模
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阻尼eKdV-Burgers方程的共形广义多辛Fourier拟谱算法
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作者 李骞 王桂霞 王一辰 《应用数学和力学》 北大核心 2025年第11期1464-1479,共16页
基于Hamilton共形广义多辛理论,研究一类阻尼eKdV-Burgers方程的共形广义多辛Fourier拟谱格式的保结构算法.首先,通过引入中间变量,将方程转化为满足局部守恒的共形广义多辛Hamilton系统,并利用Strang分裂方法,将其分裂为守恒子系统和... 基于Hamilton共形广义多辛理论,研究一类阻尼eKdV-Burgers方程的共形广义多辛Fourier拟谱格式的保结构算法.首先,通过引入中间变量,将方程转化为满足局部守恒的共形广义多辛Hamilton系统,并利用Strang分裂方法,将其分裂为守恒子系统和耗散子系统.进一步,空间上利用Fourier拟谱方法,时间上利用隐中点方法,对该系统进行离散,得到共形广义多辛Fourier拟谱格式,在周期边界条件下,该格式满足全局共形质量守恒律和动量守恒律.数值实例表明该算法是有效的,能够保持系统质量和动量衰减特性. 展开更多
关键词 耗散项 浅水效应 eKdV-Burgers方程 共形广义多辛 fourier拟谱方法 Strang分裂
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结合VMD和Fourier导数的非线性系统识别方法
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作者 田如月 黄天立 唐蕾 《振动与冲击》 北大核心 2025年第23期130-140,共11页
在处理多分量非线性信号时,信号受到噪声干扰使得传统分解方法难以自适应地分离出有效信号分量,同时,传统时频方法在识别瞬时频率时受限于谱图的时频分辨率精度和脊线算法效率等问题,传统时频分析方法识别多自由度非线性系统的瞬时频率... 在处理多分量非线性信号时,信号受到噪声干扰使得传统分解方法难以自适应地分离出有效信号分量,同时,传统时频方法在识别瞬时频率时受限于谱图的时频分辨率精度和脊线算法效率等问题,传统时频分析方法识别多自由度非线性系统的瞬时频率效果不佳。为此,提出了一种结合变分模态分解(variational mode decomposition,VMD)和Fourier导数的多自由度非线性系统识别方法。首先采用信号的傅里叶频谱确定分解模态数K,并采用VMD将多分量信号分解为K个模态分量,提取有效信号分量;然后基于Hilbert变换构造各模态分量的解析复信号;最后基于Fourier导数选取信号相邻两个时间点进行插值、求极限运算求解各分量的瞬时频率,从而识别非线性系统的动态特性。数值模拟无阻尼和有阻尼多分量信号,水平加速度简谐激励和地震激励下含Bouc-Wen滞回系统的两层剪切型结构响应,带阻尼器的三层钢框架结构振动台试验,验证了所提方法的准确性和适用性。数值模拟结果表明,相较于短时傅里叶变换和Hilbert变换,提出的结合VMD和Fourier导数方法的非线性系统瞬时频率识别精度优于短时傅里叶变换和希尔伯特变换方法;振动台试验结果表明,所提方法能准确识别地震激励下非线性结构的瞬时频率。 展开更多
关键词 非线性系统识别 多自由度 fourier导数 变分模态分解(VMD) 瞬时频率
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卫星导航通道失真下伪距偏差Fourier分解模型
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作者 高涵博 林红磊 +1 位作者 欧钢 肖志斌 《导航定位学报》 北大核心 2025年第2期103-110,共8页
针对卫星导航系统收发通道失真引起的伪距测量偏差在不同接收机相关间隔下的不一致性问题,提出一种通道失真下的伪距偏差分解模型:利用通道群时延的傅里叶(Fourier)级数分解,以多径形式表征出接收信号在通道失真下的畸变相关函数及随接... 针对卫星导航系统收发通道失真引起的伪距测量偏差在不同接收机相关间隔下的不一致性问题,提出一种通道失真下的伪距偏差分解模型:利用通道群时延的傅里叶(Fourier)级数分解,以多径形式表征出接收信号在通道失真下的畸变相关函数及随接收机相关间隔变化的过零点偏差(SCB)曲线;在此基础上,利用SCB曲线分析通道参数对接收机不同相关间隔下伪距偏差的影响,提出满足不同一致性设计要求的滤波器参数设计。实验结果表明,提出的模型计算的理论SCB曲线与仿真曲线的均方根误差为7.9 mm,相比于传统模型的均方根误差可减小78%;该模型可为接收机通道优化设计提供分析工具,并为伪距测量校准提供参考。 展开更多
关键词 导航信道 伪距偏差 滤波器 相关函数 通道非理想 傅里叶级数
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Fast full-color pathological imaging using Fourier ptychographic microscopy via closed-form model-based colorization 被引量:2
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作者 Yanqi Chen Jiurun Chen +4 位作者 Zhiping Wang Yuting Gao Yonghong He Yishi Shi An Pan 《Advanced Photonics Nexus》 2025年第2期7-16,共10页
Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution fo... Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering. 展开更多
关键词 fourier ptychographic microscopy color transfer dual-color-space constrained model
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基于Exponent Fourier矩的双图像水印方法
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作者 刘西林 贺贤浩 +2 位作者 张昊 岳俊宏 陈泽华 《太原理工大学学报》 北大核心 2025年第3期474-484,共11页
【目的】针对目前大多数图像水印方案都设计为在单一图像中嵌入水印,会导致效率不够高的问题,探讨将水印同时嵌入两幅图像中,以在保证算法鲁棒性能的前提下提高效率。【方法】首先,通过复数表示法将两幅原始图像组合在一起。然后,采用... 【目的】针对目前大多数图像水印方案都设计为在单一图像中嵌入水印,会导致效率不够高的问题,探讨将水印同时嵌入两幅图像中,以在保证算法鲁棒性能的前提下提高效率。【方法】首先,通过复数表示法将两幅原始图像组合在一起。然后,采用量化调制的信息嵌入方法将水印嵌入到组合图像的Exponent Fourier矩中,通过修改前后的Exponent Fourier矩的扰动量重构图像生成补偿图像,将原始组合图像与补偿图像叠加得到嵌入水印的组合图像。最后,对嵌入水印的组合图像进行分解,得到两幅加水印的图像。在提取水印时,需要两幅加入水印的图像,然后进行组合,在组合后的图像中提取水印。【结果】实验验证了所提方法的可行性和其较强的鲁棒性,与传统PCET矩的水印方法相比,所提水印方法对5×5中值滤波、5×5均值滤波、方差为0.03的高斯噪声、噪声密度为0.03的椒盐噪声、压缩因子为10的JPEG压缩攻击,其BER值分别降低了36%、44%、45%、59%、29%;在提取水印时,与分别处理两幅图像相比,提取时间缩短了50%。 展开更多
关键词 图像水印 双图像水印 Exponent fourier
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A Programming Method for Mean Behavior of Fourier Coefficients of Modular Forms on Sparse Sequences
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作者 HU Yuanrui YAO Weili 《数学进展》 北大核心 2025年第4期709-724,共16页
Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)at... Let f be a primitive holomorphic cusp form with even integral weight k≥2 for the full modular groupΓ=SL(2,Z)andλ_(sym^(j)f)(n)be the n-th coefficient of Dirichlet series of j-th symmetric L-function L(s,sym^(j)f)attached to f.In this paper,we study the mean value distribution over a specific sparse sequence of positive integers of the following sum∑(a^(2)+b^(2)+c^(2)+d^(2)≤x(a,b,c,d)∈Z^(4))λ_(sym^(j))^(i)f(a^(2)+b^(2)+c^(2)+d^(2))where j≥2 is a given positive integer,i=2,3,4 andαis sufficiently large.We utilize Python programming to design algorithms for higher power conditions,combining Perron's formula,latest results of representations of natural integers as sums of squares,as well as analytic properties and subconvexity and convexity bounds of automorphic L-functions,to ensure the accuracy and verifiability of asymptotic formulas.The conclusion we obtained improves previous results and extends them to a more general settings. 展开更多
关键词 automorphic L-function holomorphic cusp form fourier coefficient
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AI-driven Fourier Ptychography and Its Insight for“AI+Optics”(Invited)
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作者 PAN An WANG Aiye +4 位作者 FENG Tianci GAO Huiqin WANG Siyuan XU Jinghao LI Xuan 《光子学报》 北大核心 2025年第9期146-170,共25页
Fourier Ptychographic Microscopy(FPM)is a high-throughput computational optical imaging technology reported in 2013.It effectively breaks through the trade-off between high-resolution imaging and wide-field imaging.In... Fourier Ptychographic Microscopy(FPM)is a high-throughput computational optical imaging technology reported in 2013.It effectively breaks through the trade-off between high-resolution imaging and wide-field imaging.In recent years,it has been found that FPM is not only a tool to break through the trade-off between field of view and spatial resolution,but also a paradigm to break through those trade-off problems,thus attracting extensive attention.Compared with previous reviews,this review does not introduce its concept,basic principles,optical system and series of applications once again,but focuses on elaborating the three major difficulties faced by FPM technology in the process from“looking good”in the laboratory to“working well”in practical applications:mismatch between numerical model and physical reality,long reconstruction time and high computing power demand,and lack of multi-modal expansion.It introduces how to achieve key technological innovations in FPM through the dual drive of Artificial Intelligence(AI)and physics,including intelligent reconstruction algorithms introducing machine learning concepts,optical-algorithm co-design,fusion of frequency domain extrapolation methods and generative adversarial networks,multi-modal imaging schemes and data fusion enhancement,etc.,gradually solving the difficulties of FPM technology.Conversely,this review deeply considers the unique value of FPM technology in potentially feeding back to the development of“AI+optics”,such as providing AI benchmark tests under physical constraints,inspirations for the balance of computing power and bandwidth in miniaturized intelligent microscopes,and photoelectric hybrid architectures.Finally,it introduces the industrialization path and frontier directions of FPM technology,pointing out that with the promotion of the dual drive of AI and physics,it will generate a large number of industrial application case,and looks forward to the possibilities of future application scenarios and expansions,for instance,body fluid biopsy and point-of-care testing at the grassroots level represent the expansion of the growth market. 展开更多
关键词 Computational optical imaging fourier ptychography Artificial Intelligence Highthroughput imaging Multimodal imaging
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25点Laplace-Fourier域二维标量波有限差分数值模拟方法
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作者 王超群 吴国忱 杨凌云 《地球物理学进展》 北大核心 2025年第6期2698-2710,共13页
频率域有限差分正演的计算精度和效率决定了波形反演的质量,选择合适的差分格式是频率域正演的基础.目前基于旋转坐标系统的优化差分格式广泛的应用,但其受限于等间距采样的条件,为改善状况选择平均导数法的优化差分格式,其既可以适用... 频率域有限差分正演的计算精度和效率决定了波形反演的质量,选择合适的差分格式是频率域正演的基础.目前基于旋转坐标系统的优化差分格式广泛的应用,但其受限于等间距采样的条件,为改善状况选择平均导数法的优化差分格式,其既可以适用于不同间距采样,同时又可以提高采样精度.因此,本文针对二维标量波动方程在传统9点有限差分的基础上发展了一种基于平均导数(Average-Derivative Method,ADM)25点有限差分优化差分格式,经优化后ADM-25点有限差分格式仅需每个最小伪波长大约5个点,即可实现1%以内的归一化误差.引入最佳匹层吸收边界(Perfect Matched Layer,PML),进而计算并求取不同空间采样间距比情况下25点优化差分系数,实现纵横向之间非等间隔数值模拟.数值算例结果表明,基于平均导数法25点差分格式比经典的9点差分格式具有更高的模拟精度. 展开更多
关键词 二维标量波方程 Laplace-fourier 有限差分 优化系数
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Assessment of Optimal Use, Maintenance, Repair and Calibration of Radiation Monitoring Instruments in Nigeria
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作者 Samuel Mofolorunsho Oyeyemi Olumide Olaife Akerele +5 位作者 Sunday Ufuoma Obarhua Francis Adole Agada Wasiu Kofoworola Ayuba Helen Enikpi Alakiu David Olakanmi Olaniyi Ethel Ebere Ofoegbu 《World Journal of Nuclear Science and Technology》 2025年第1期1-16,共16页
The response and performance of radiation detectors for accurate measurements and effective use for radiological safety in medical, industrial, and nuclear sectors are based on the optimal use, maintenance, repair and... The response and performance of radiation detectors for accurate measurements and effective use for radiological safety in medical, industrial, and nuclear sectors are based on the optimal use, maintenance, repair and calibration of radiation monitoring instruments in a secondary standard dosimetry laboratory. In Nigeria, the suboptimal performances of these instruments are attributed to inadequate maintenance practices, insufficient calibration, and limited awareness of proper equipment handling for optimal use. This study assesses the current practices related to the optimal use, maintenance, repair, and calibration of radiation detection equipment across Nigeria’s six geopolitical zones. Using a cross-sectional survey approach, data were collected from Ninety (90) radiation monitoring equipment operators, Radiation Safety Officers, and frontline responders to evaluate their knowledge, awareness, and practices concerning equipment usage, operation, storage, handling, and calibration. The findings reveal significant gaps in knowledge of usage (trained is 43.2%, not trained is 56.8%) and inconsistencies in maintenance practices (as indicated by the regression analysis (β = 0.51, p < 0.01), particularly regarding specialized instruments such as the PackEye, Mobile Detection System (MDS), Radionuclide Identifinder (RID), and Personal Radiation Detectors (PRD). While there is high awareness of the need for regular calibration and handling training, the lack of standardized protocols and training alignment poses challenges to the effective use of these instruments. This study underscores the importance of comprehensive training programs, standardized maintenance protocols, and enhanced awareness initiatives to optimize the usage, performance and safety of radiation monitoring instruments in Nigeria. 展开更多
关键词 Radiation Monitoring instruments Detectors CALIBRATION Radiation Safety Officers PackEye Radionuclide Identifinder Personal Radiation Detectors
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算术数列中Fourier系数的均值估计
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作者 武毅 《兰州文理学院学报(自然科学版)》 2025年第1期1-6,共6页
设f(z)是全模群上权为偶数k的全纯本原尖形式,L(s,sym^(4)f)是与f对应的4次对称幂L-函数,λ_(sym^(4)f)(n)是L(s,sym^(4)f)的Fourier展开的第n个标准化系数.本文借助对称幂L-函数的解析性质研究了算术数列中4次对称幂L-函数Fourier系数... 设f(z)是全模群上权为偶数k的全纯本原尖形式,L(s,sym^(4)f)是与f对应的4次对称幂L-函数,λ_(sym^(4)f)(n)是L(s,sym^(4)f)的Fourier展开的第n个标准化系数.本文借助对称幂L-函数的解析性质研究了算术数列中4次对称幂L-函数Fourier系数的均值估计,即Σ_(n≤x,n≡l(q))λ_(sym^(4)f)(n^(2)). 展开更多
关键词 全纯本原尖形式 对称幂L-函数 算术数列 fourier系数
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The Impact of Quality Nursing on Instrument Quality Management and Department Satisfaction in the Management of Reusable Instruments in the Central Sterile Supply Department
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作者 Jie Li 《Journal of Clinical and Nursing Research》 2025年第6期385-391,共7页
Objective:To evaluate the effectiveness of quality nursing in the management of reusable instruments in the Central Sterile Supply Department(CSSD).Methods:Eleven nurses from the CSSD department were selected from Jan... Objective:To evaluate the effectiveness of quality nursing in the management of reusable instruments in the Central Sterile Supply Department(CSSD).Methods:Eleven nurses from the CSSD department were selected from January to October 2024,and quality nursing activities were implemented in the management of reusable instruments.The completion of quality indicators was analyzed.The instrument quality management scores,department satisfaction,and nurses’professional ability scores before and after nursing management were compared.Results:After nursing intervention,the qualified rates of initial cleaning and final cleaning of sterilization instruments were 99.66%and 100%,respectively.The qualified rate of packaging was 99.97%,the wet package rate was 0.1‰,the loading qualified rate was 99.88%,and the qualified rate of distribution was 99.99%.After nursing intervention,the nurses’instrument quality management scores,department satisfaction,and nurses’professional ability scores were all higher than those before nursing intervention(P<0.05).Conclusion:Quality nursing activities can improve the cleaning,packaging,and sterilization qualified rates of reusable instruments in the CSSD,enhance the effect of instrument quality management,obtain higher department satisfaction from nurses,cultivate their professional abilities,and possess significant nursing management advantages. 展开更多
关键词 Quality nursing Central Sterile Supply Department Reusable instrument management Instrument quality management Department satisfaction
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强非退化条件下Fourier积分算子的加权估计
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作者 刘亚兵 陶双平 《湖北大学学报(自然科学版)》 2025年第4期517-521,共5页
本工作主要目的是研究Fourier积分算子的加权估计并证明当a∈S_(ρ,δ)^(m),0<ρ≤1,0≤δ<1,Ф∈Φ^(2)时,在强非退化条件m=ρ-n/2下,Fourier积分算子T_(φ,a)在加权L^(p)空间上是有界的。
关键词 fourier积分算子 Hörmander类 加权L^(p)空间 A_(p)权
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The Expanding Role of Instruments and Equipment in Medical Imaging
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作者 Arturo Chiti 《iRADIOLOGY》 2025年第5期325-326,共2页
This editorial introduces a special issue dedicated to the technical advancements in medical imaging.Medical imaging is an essential component of modern medicine,enabling the detection and analysis of structures and f... This editorial introduces a special issue dedicated to the technical advancements in medical imaging.Medical imaging is an essential component of modern medicine,enabling the detection and analysis of structures and functions within the human body.Among the key imaging modalities are X‐ray,ultrasound,computed tomography(CT),magnetic resonance imaging(MRI),positron emission tomography(PET),and single‐photon emission computed tomography.Each of these technologies plays a vital role in diagnostics and research,and their continued development drives progress in diagnostic imaging and related disciplines. 展开更多
关键词 hybrid imaging INSTRUMENTATION medical imaging
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