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磁共振IDEAL-IQ序列定量分析腹腔内脏脂肪含量与2型糖尿病的关系
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作者 王金凤 罗琳 +1 位作者 陈强 原小军 《实用医学杂志》 CAS 北大核心 2024年第16期2256-2262,共7页
目的探讨腹腔内脏脂肪含量与糖尿病发生的关系,进而探讨其预测T2DM发病的可行性。方法收集行腹部3.0T MRI检查并有T2DM患者45例(T2DM组),对照组80例,应用IDEAL软件进行图像自动重组,获得脂肪分数(FF图)、弛豫率(R2*)、脂相、水相、同反... 目的探讨腹腔内脏脂肪含量与糖尿病发生的关系,进而探讨其预测T2DM发病的可行性。方法收集行腹部3.0T MRI检查并有T2DM患者45例(T2DM组),对照组80例,应用IDEAL软件进行图像自动重组,获得脂肪分数(FF图)、弛豫率(R2*)、脂相、水相、同反相位图像。将FF图传至AW 4.6工作站,由两名观察者采用双盲法对FF图进行测量。应用ITK-SNAP软件采用阈值分割法半自动勾画腹腔内脏脂肪(VAT)及皮下脂肪组织(SAT),并计算体积。采用SPSS 26.0软件对数据进行统计学分析。结果(1)T2DM组的腹腔内脏脂肪组织体积(VATV)、肝脏脂肪分数(HFF)、胰腺脂肪分数(PFF)、甘油三酯(TG)及空腹血糖(FBG)均高于对照组,高密度脂蛋白(HDL)低于对照组,差异有统计学意义(P<0.05);(2)ROC曲线分析示:PFF判断是否患T2DM的曲线下面积(AUC)为0.656(P<0.01,95%CI:0.534~0.777),截断值为8.44%,敏感度为50%,特异度为82.5%;HFF判断是否患T2DM的AUC为0.744(P<0.05,95%CI:0.637~0.851),截断值、敏感度、特异度分别为2.99%、97.5%、42.5%。男性患者VATV判断T2DM的最佳阈值为3466 cm^(3),敏感度为63.2%,特异度为89.5%,AUC为0.78(P<0.01),联合SATV、PFF及HFF时,敏感度为78.9%,特异度为84.2%,AUC为0.839(P<0.01);女性患者利用VATV诊断T2DM的最佳阈值为2103 cm^(3),利用该阈值判断T2DM的敏感度为66.7%,特异度为66.7%,AUC为0.68(P<0.05),联合SATV、PFF及HFF时,敏感度为90.5%,特异度为76.2%,AUC为0.909(P<0.01)。(3)TG和FBG每增加1个单位,患T2DM的风险就分别提升了3986.3%及417.1%,即TG和FBG是T2DM发病的独立预测因子。结论PFF、HFF及VATV单独在预测T2DM发病方面,检验效能较低。VATV联合SATV、PFF、HFF预测T2DM发生的检验效能显著提高,其敏感度及特异度亦均明显提高。IDEAL-IQ技术是评估T2DM患者腹腔内异位脂肪组织沉积定量的便捷的方法,具有简单、稳定性好及重复性高的优势。 展开更多
关键词 2型糖尿病 内脏脂肪组织 核磁共振 ideal-IQ
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On the Optimal Initial Inner-Core Size for Tropical Cyclone Intensification: An Idealized Numerical Study
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作者 Rong FEI Yuqing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2141-2155,共15页
Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of... Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of maximum wind—RMW)varied from 20–180 km in idealized simulations using two different numerical models, we found a nonmonotonic dependence of the lifetime maximum intensification rate(LMIR) on the inner-core size. Namely, there is an optimal innercore size for the LMIR of a TC. Tangential wind budget analysis shows that, compared to large TCs, small TCs have large inward flux of absolute vorticity due to large absolute vorticity inside the RMW. However, small TCs also suffer from strong lateral diffusion across the eyewall, which partly offsets the positive contribution from large inward flux of absolute vorticity. These two competing processes ultimately lead to the TC with an intermediate initial inner-core size having the largest LMIR. Results from sensitivity experiments show that the optimal size varies in the range of 40–120 km and increases with higher sea surface temperature, lower latitude, larger horizontal mixing length, and weaker initial TC intensity. The 40–120 km RMW corresponds to the inner-core size most commonly found for intensifying TCs in observations, suggesting the natural selection of initial TC size for intensification. This study highlights the importance of accurate representation of TC inner-core size to TC intensity forecasts by numerical weather prediction models. 展开更多
关键词 tropical cyclones INTENSIFICATION inner-core size idealized simulations
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INCOMPRESSIBLE LIMIT OF IDEAL MAGNETOHYDRODYNAMICS IN A DOMAIN WITH BOUNDARIES
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作者 Qiangchang JU Jiawei WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1441-1465,共25页
We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat boundary.The boundary condition is characteristic and the initial data is general.We first e... We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat boundary.The boundary condition is characteristic and the initial data is general.We first establish the uniform existence of classical solutions with respect to the Mach number.Then,we prove that the solutions converge to the solution of the incompressible MHD system.In particular,we obtain a stronger convergence result by using the dispersion of acoustic waves in the half space. 展开更多
关键词 incompressible limit ideal MHD equations boundary condition general initial data
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基于“IDEAL”模式的物理问题解决能力培养研究
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作者 杨卓璇 林钦 《中学理科园地》 2024年第3期46-48,51,共4页
学生“物理问题解决能力弱”是长期困扰物理教学的问题,认知心理学关于问题解决的“IDEAL”模式为该问题的研究提供了新的视角。以2022年全国乙卷理综第25题为例,借助“IDEAL”模式可以清晰地梳理问题解决的过程,明确各阶段学生遇到的... 学生“物理问题解决能力弱”是长期困扰物理教学的问题,认知心理学关于问题解决的“IDEAL”模式为该问题的研究提供了新的视角。以2022年全国乙卷理综第25题为例,借助“IDEAL”模式可以清晰地梳理问题解决的过程,明确各阶段学生遇到的困难及成因。研究发现,借助“读思达”教学法,通过粗读、精读等过程,可以有效帮助学生建构物理模型、理清物理过程,从而提高物理问题解决能力。 展开更多
关键词 问题解决 ideal”模式 “读思达”教学法
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For the Ideal Homeland
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作者 ZHOU LIN 《China Today》 2024年第7期62-64,共3页
A town planner combines British experience with Chinese concept of harmony to build green,low-carbon,and sustainable cities.YANG Wei is a woman who wears many hats.An internationally renowned town planner and urban de... A town planner combines British experience with Chinese concept of harmony to build green,low-carbon,and sustainable cities.YANG Wei is a woman who wears many hats.An internationally renowned town planner and urban designer,she is held in high esteem in the academic and planning communities in the U.K.and is a fellow of the U.K.Academy of Social Sciences and former president of the Royal Town Planning Institute(RTPI)based in London.She is also chief executive and co-founder of the Digital Task Force for Planning(DTFP),a non-profit social enterprise,and founding director of London-based planning and urban design firm Wei Yang&Partners. 展开更多
关键词 FOUNDING HARMONY ideal
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Yeats’s Ideals:Women Old and Young
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作者 DONG Qian 《Journal of Literature and Art Studies》 2024年第5期330-334,共5页
William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,... William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,Lady Gregory,and Georgie Hyde-Lees.Even in Yeats’s poetry involved with symbolism,it is worth noting that his employment of symbols has used these women as the archetypes,and that the historical context rendered Yeats’s representations of them in his poetry all the more interesting. 展开更多
关键词 idealS WOMEN representation SYMBOLISM OCCULT
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磁共振IDEAL-IQ序列测量肝脏脂肪含量的可行性研究
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作者 吴佳芳 许乙凯 罗婉莉 《现代仪器与医疗》 CAS 2024年第4期67-75,共9页
目的 探究IDEAL-IQ序列测量肝脏脂肪含量的准确性,以及影响测量准确性的因素。方法 利用GE DISCOVERY MR750 3.0T的单通道头线圈、八通道头线圈以及八通道腹部线圈,对配置的不同浓度的水脂混合溶液模体进行高参数扫描。在GE AW4.6工作... 目的 探究IDEAL-IQ序列测量肝脏脂肪含量的准确性,以及影响测量准确性的因素。方法 利用GE DISCOVERY MR750 3.0T的单通道头线圈、八通道头线圈以及八通道腹部线圈,对配置的不同浓度的水脂混合溶液模体进行高参数扫描。在GE AW4.6工作站上进行多次脂肪含量测量,并对测量数值进行线性回归分析,讨论测量值与已知配置值的相关性,分析配置水脂混合模体在不同线圈中测量的准确性。结果 对于已知浓度的水脂混合溶液模型,IDEAL-IQ序列在三个线圈测量数据的一元线性回归讨论中,三个回归模型的P<0.0001,测量模型均在α=0.0001的水平上显著性明显,拟合较好,置信度达到99.99%。不同线圈在同参数扫描的情况下,由于信噪比不同,在图像中出现明显噪点,在使用小ROI测量时,会使得同一层面测量结果出现较大偏差。结论 IDEAL-IQ序列运用于脂肪含量的定量测量是可行可靠的,并且精准性较高。但扫描图像的质量对于测量稳定性以及准确性有影响,图像噪声越大则测量结果越不稳定,测量值的偏差越大。在临床扫描条件下,临床医师的测量应该采用适当ROI多点测量取平均值的方式进行肝脏脂肪含量的测量,同时还应该避开肝脏扫描层中的初始层及末端层。如果选取区域落于初始层及末端层,则可能会导致脂肪含量的过估计。 展开更多
关键词 磁共振成像技术 ideal-IQ 脂肪含量测量 临床精准测量1
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基于改进AdvSemiSeg的半监督遥感影像作物制图方法
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作者 翟雪东 韩文霆 +3 位作者 马伟童 崔欣 李广 黄沈锦 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期196-204,共9页
作物精准遥感制图对于农业资源调查与管理具有重要意义。深度学习为实现精准高效作物制图提供了技术支持。为了缓解深度学习对标记样本的依赖,本文提出了一种改进AdvSemiSeg的半监督遥感影像作物制图方法。所提方法引入STMF-DeepLabv3+... 作物精准遥感制图对于农业资源调查与管理具有重要意义。深度学习为实现精准高效作物制图提供了技术支持。为了缓解深度学习对标记样本的依赖,本文提出了一种改进AdvSemiSeg的半监督遥感影像作物制图方法。所提方法引入STMF-DeepLabv3+作为对抗学习中的生成网络,通过Swin Transformer(ST)和多尺度特征融合(Multi-scale fusion, MF)模块提高生成网络特征编码能力和语义表达能力,改善遥感影像作物分割效果;此外,在判别网络中引入通道注意力(Efficient channel attention, ECA)模块,对不同通道特征图的表征信息进行自适应学习,增强判别网络对不同通道特征的感知能力。模型训练过程中,判别网络为生成网络提供高质量的伪标签和对抗损失,有效提高生成网络的泛化能力。采用所提方法与几种先进的半监督语义分割方法对内蒙古河套灌区遥感影像种植信息进行提取,本文方法性能最优。 展开更多
关键词 遥感 作物制图 半监督学习 生成对抗网络 多尺度特征融合 通道注意力
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An Empirical Evaluation of the Impact of Moral and Law Course Teaching on the Effectiveness of University Students’Ideals and Beliefs Education
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作者 Aiai Yang 《Journal of Contemporary Educational Research》 2024年第10期148-152,共5页
The Moral and Law course serves as a critical platform for educating university students about ideals and beliefs,and it has a significant impact on the effectiveness of ideals and beliefs education.This paper establi... The Moral and Law course serves as a critical platform for educating university students about ideals and beliefs,and it has a significant impact on the effectiveness of ideals and beliefs education.This paper establishes a mechanism through which Moral and Law course teaching influences the effectiveness of ideals and beliefs education and conducts an empirical evaluation.The results reveal that factors such as the relevance and applicability of the teaching content,the integration of theory and practice,the innovation,interactivity,and participation of teaching methods,as well as classroom atmosphere,teaching facilities,and campus culture,all have a significant positive impact on the effectiveness of ideals and beliefs education for university students. 展开更多
关键词 ideals and beliefs education Moral and Law course Empirical evaluation
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基于磁共振IDEAL-IQ分析胰腺脂肪含量及其影响因素
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作者 郭俊 焦志云 《影像研究与医学应用》 2024年第20期21-24,共4页
目的:运用磁共振脂肪定量最小二乘估计和不对称回波迭代分解水和脂肪成像(IDEAL-IQ)测量胰腺脂肪分数(PFF),并分析其相关影响因素。方法:选取2021年6月—2023年3月扬州大学附属医院收治的169例患者为研究对象,收集患者住院期间年龄,身... 目的:运用磁共振脂肪定量最小二乘估计和不对称回波迭代分解水和脂肪成像(IDEAL-IQ)测量胰腺脂肪分数(PFF),并分析其相关影响因素。方法:选取2021年6月—2023年3月扬州大学附属医院收治的169例患者为研究对象,收集患者住院期间年龄,身高、体质量、空腹血糖(FBG)、总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)以及IDEAL-IQ相关参数PFF、肝脏脂肪分数(HFF)、内脏脂肪面积(VFA)等资料,根据PFF结果将受检者分为高脂肪组(PFF≥4.17%)和低脂肪组(PFF<4.17%),比较高脂肪组与低脂肪组间各指标差异,并采用Pearson线性相关分析评价各指标与PFF的相关性。结果:169例受检者85例PFF≥4.17%,设为高脂肪组;84例PFF<4.17%,设为低脂肪组。高脂肪组患者年龄、HFF、BMI、FPC、TC、TG、VFA均高于胰腺低脂肪组,而HDL-C低于胰腺低脂肪组,差异有统计学意义(P<0.05)。PFF与年龄、HFF、BMI、FBG、TG、TC、VFA呈正相关性,与HDL-C呈负相关性(P<0.05)。结论:磁共振IDEAL-IQ技术可用于PFF的测量,PFF与HFF、BMI、FPC、TC、TG、VFA及HDL-C具有一定相关性。 展开更多
关键词 脂肪胰 胰腺脂肪分数 肝脏脂肪分数 磁共振 ideal-IQ
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iDEAL-CIO: Instant Digital Express Advocated “Magic Lamp” for Cloud Intelligence Outlet
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作者 Sheldon Liang Paul Anthony Miller +1 位作者 Brendan Shane Rowe Alexis Rainbow 《Intelligent Information Management》 2024年第1期35-63,共29页
Instant Digital Express iDEAL-CIO The “Magic Lamp” for Cloud Intelligence Outlet, which has been recommended, combines innovations to satisfy modern users’ needs and efficiently sift through the ever-expanding amou... Instant Digital Express iDEAL-CIO The “Magic Lamp” for Cloud Intelligence Outlet, which has been recommended, combines innovations to satisfy modern users’ needs and efficiently sift through the ever-expanding amount of intelligent content stored in the cloud. One such innovation introduces a ground-breaking concept to remove superfluous and outdated sequential search patterns that overwhelm the user and computer in order to better serve the user in an eclectic & elastic and multidimensional approach to finding, grouping, assimilation, organizing, and delivering archival content. The cloud intelligence outlet (CIO) is presented in this article as the perfect magic lamp option for quick digital express advocacy. The grouping, indexing, folding, and targeting (GIFT) method of multidimensional online synthetic/analytical intelligent content (MOSAIC) for adaptive intelligence is the fundamental intelligent aggregation and automated process of the Magic Lamp. Three perspectives above this new ideal framework are available to observe: The Magic Lamp proposes contextual and multiple analytical tracks to improve cloud intelligence services conceptually. Technically speaking, MOSAIC combines domain-specific services for a wide range of international users, and through the usage of Cloud Intelligence Outlet, GIFT operationally activates grouping, indexing, folding, and targeting to promote decent experience and in-depth research on target for users’ wants. Because of this, iDEAL-CIO works in tandem with cloud extraction, digital transformation, and archival loading to provide improved service through the readily accessible cloud intelligence outlet. 展开更多
关键词 ideal-CIO MOSAIC Multidimensional Online Synthetic/Analytical Intelligent Content
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基于事件触发的奇异semi-Markov跳变系统的有限时间控制
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作者 刘雪华 嵇小辅 《控制工程》 CSCD 北大核心 2024年第6期1123-1129,共7页
为减少不必要的网络资源传输,解决实际复杂系统的有限时间问题,提出一种基于事件触发方案的奇异semi-Markov跳变系统的有限时间控制器设计方法。在事件触发方案下,用系统的时滞表示网络诱导时延,闭环系统可以建模为一个时滞系统。首先,... 为减少不必要的网络资源传输,解决实际复杂系统的有限时间问题,提出一种基于事件触发方案的奇异semi-Markov跳变系统的有限时间控制器设计方法。在事件触发方案下,用系统的时滞表示网络诱导时延,闭环系统可以建模为一个时滞系统。首先,通过构造合适的Lyapunov-Krasovskii泛函,以严格矩阵不等式的形式给出充分条件,以使事件触发方案下的闭环系统正则、无脉冲、随机有限时间有界;然后,通过求解矩阵不等式,得到状态反馈控制器的参数;最后,给出一个数值示例,通过仿真证明所提方法的有效性。 展开更多
关键词 奇异半马尔可夫跳变系统 事件触发方案 有限时间稳定 线性矩阵不等式
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Estimating the Drought-Induced Yield Loss for Winter Wheat in a Semi-Arid Region of the Southern United States Using a Drought Index
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作者 Prem Woli Qingwu Xue +2 位作者 Gerald R. Smith Charles R. Long Francis M. Rouquette Jr. 《Agricultural Sciences》 2024年第8期812-829,共18页
The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This regio... The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This region is prone to drought and is projected to experience a drier climate. Droughts that coincide with the critical phenological phases of a crop can be remarkably costly. Although drought cannot be prevented, its losses can be minimized through mitigation measures if it is predicted in advance. Predicting yield loss from an imminent drought is an important need of stakeholders. One way to fulfill this need is using an agricultural drought index, such as the Agricultural Reference Index for Drought (ARID). Being plant physiology-based, ARID can represent drought-yield relationships accurately. This study developed an ARID-based yield model for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to water stress. The reasonable values of the drought sensitivity coefficients of the yield model indicated that it could reflect the phenomenon of water stress decreasing the winter wheat yields in this region reasonably. The values of the various metrics used to evaluate the model, including Willmott Index (0.86), Nash-Sutcliffe Index (0.61), and percentage error (26), indicated that the yield model performed fairly well at predicting the drought-induced yield loss for winter wheat. The yield model may be useful for predicting the drought-induced yield loss for winter wheat in the study region and scheduling irrigation allocation based on phenological phase-specific drought sensitivity. 展开更多
关键词 ARID DROUGHT Drought index Growth-stage Model Phenological-Phase Prediction semi-ARID Wheat Yield
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Reversible Semi-Fragile Watermarking Technique for Integrity Control of Relational Database
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作者 Ali Hamadou Abdoul Aziz Issaka Hassane +1 位作者 Lanciné Camara Harouna Naroua 《Engineering(科研)》 2024年第9期309-323,共15页
Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differ... Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differentiate between legal and malicious modifications. In this paper, we introduce a novel lossless semi-fragile scheme based on prediction-error expansion for content protection of relational database. In the proposed method, all attributes in a database relation are first classified according to their sensitivity to legitimate updates. Then, the watermark is embedded by expanding the prediction error of the two least significant digits of securely selected attributes. At watermark extraction, the proposed method has the ability to fully restore the original data while detecting and localizing tampering. The applicability of our method is demonstrated theoretically and experimentally. 展开更多
关键词 semi-Fragile Watermarking Integrity Control REVERSIBILITY Prediction-Error Expansion
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Decentralized Semi-Supervised Learning for Stochastic Configuration Networks Based on the Mean Teacher Method
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作者 Kaijing Li Wu Ai 《Journal of Computer and Communications》 2024年第4期247-261,共15页
The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy ... The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy of decentralized SCN algorithms while effectively protecting user privacy. To this end, we propose a decentralized semi-supervised learning algorithm for SCN, called DMT-SCN, which introduces teacher and student models by combining the idea of consistency regularization to improve the response speed of model iterations. In order to reduce the possible negative impact of unsupervised data on the model, we purposely change the way of adding noise to the unlabeled data. Simulation results show that the algorithm can effectively utilize unlabeled data to improve the classification accuracy of SCN training and is robust under different ground simulation environments. 展开更多
关键词 Stochastic Neural Network Consistency Regularization semi-Supervised Learning Decentralized Learning
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Solution of the Matrix Second Semi-Tensor Product Equation A ∘ l X ∘ l B=C
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作者 Hao Zhang 《Journal of Applied Mathematics and Physics》 2024年第10期3261-3280,共20页
In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time,... In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time, the compatibility conditions, the sufficient and necessary conditions and the specific solution methods for the matrix solution are given. Secondly, we further consider the solvability of the second semi-tensor product equation of the matrix. For each part, several examples are given to illustrate the validity of the results. 展开更多
关键词 Matrix Equation The Second semi-Tensor Product Compatibility Condition Sufficient and Necessary Conditions VECTORIZATION
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Pseudo-Semi-Overlap Functions-Based Fuzzy Rough Sets Applied to Image Edge Extraction
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作者 Ran Yin Minge Chen +2 位作者 Yu Liu Yafei Zhao Jianwei Li 《Journal of Applied Mathematics and Physics》 2024年第7期2347-2366,共20页
As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and furth... As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and further extended for applications in image edge extraction. Firstly, a new clustering function, the pseudo-semi-overlap function, is introduced by eliminating the symmetry and right continuity present in the overlap function. The relaxed nature of this function enhances its applicability in image edge extraction. Secondly, the definitions of (I, PSO)-fuzzy rough sets are provided, using (I, PSO)-fuzzy rough sets, a pair of new fuzzy mathematical morphological operators (IPSOFMM operators) is proposed. Finally, by combining the fuzzy C-means algorithm and IPSOFMM operators, a novel image edge extraction algorithm (FCM-IPSO algorithm) is proposed and implemented. Compared to existing algorithms, the FCM-IPSO algorithm exhibits more image edges and a 73.81% decrease in the noise introduction rate. The outstanding performance of (I, PSO)-fuzzy rough sets in image edge extraction demonstrates their practical application value. 展开更多
关键词 Pseudo-semi-Overlap Functions Fuzzy Rough Set Fuzzy Mathematical Morphology Image Edge Extraction
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磁共振脂肪定量技术IDEAL-IQ评价腰椎骨质疏松严重程度的价值 被引量:3
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作者 成东亮 冯红梅 +5 位作者 文戈 关炜 吴耀忠 张文强 洪居陆 高明勇 《中国CT和MRI杂志》 2023年第5期157-159,共3页
目的 探讨基于MRI迭代最小二乘法水脂分离定量技术(IDEAL-IQ)的椎体骨髓脂肪分数(FF)值在评估腰椎骨质疏松严重程度中的价值。方法 收集88例同时接受双能X线骨密度测量(DXA)和腰椎IDEAL-IQ序列检查的患者,根据DXA结果分为正常骨量组(36... 目的 探讨基于MRI迭代最小二乘法水脂分离定量技术(IDEAL-IQ)的椎体骨髓脂肪分数(FF)值在评估腰椎骨质疏松严重程度中的价值。方法 收集88例同时接受双能X线骨密度测量(DXA)和腰椎IDEAL-IQ序列检查的患者,根据DXA结果分为正常骨量组(36例)、低骨量组(23例)和骨质疏松组(29例),并在IDEAL-IQ序列脂肪分数图中测量椎体的脂肪分数;应用单因素方差分析比较3组椎体的FF值,ROC曲线评估诊断效能;FF值与年龄、身高、体重、BMI指数以及BMD值进行Pearson相关分析。结果 正常骨量组、低骨量组、骨质疏松组FF值分别为(38.84±6.75)%、(51.96±7.65)%、(58.39±12.81)%,总体及组间比较差异显著(P<0.05);FF值识别正常组、低骨量组的AUC为0.797,以46.85%为阈值,敏感度、特异度分别为73.91%、80.56%;FF值识低骨量组、骨质疏松组的AUC为0.691,以57.12%为阈值,敏感度、特异度分别为79.31%、69.57%。FF值与年龄呈正相关(P<0.001,r=0.6059);FF与身高(P<0.001,r=-0.3783)、体重(P<0.001,r=-0.4686)、BMI(P<0.001,r=-0.3649)、BMD(p=0.01,r=-0.2738)呈负相关;与性别无明确相关性。结论 IDEAL-IQ能够精准量化椎体的骨髓脂肪含量,对评估骨质疏松症严重程度有一定价值,有助于从骨质量层面反映骨质疏松状态。 展开更多
关键词 磁共振成像 ideal IQ 骨质疏松 骨密度
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SEMI标准在半导体制造设备中的应用 被引量:2
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作者 韦薇 林煦呐 +2 位作者 张帅 谢琼 杨师 《电子工业专用设备》 2023年第2期58-63,共6页
SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料... SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料的使用效率标准、SECS/GEM通讯标准及其研究应用现状;提出了我国半导体产业的快速发展需要加大SEMI标准的普及应用。 展开更多
关键词 半导体制造设备 semi S2标准 semi F47标准
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3.0 T磁共振T_(2)WI IDEAL及DTI在腰椎间盘退行性变中应用 被引量:3
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作者 黄恩善 莫志英 李瑞雄 《生物医学工程与临床》 CAS 2023年第2期150-154,共5页
目的 探讨3.0 T磁共振T_(2)加权成像(T_(2)WI)、三点法非对称回波水脂分离(IDEAL)成像及扩散张量成像(DTI)在腰椎间盘退行性变评估中的应用价值。方法 选择100例腰椎间盘退行性变患者,其中男性51例,女性49例;年龄14~85岁,平均年龄49.4岁... 目的 探讨3.0 T磁共振T_(2)加权成像(T_(2)WI)、三点法非对称回波水脂分离(IDEAL)成像及扩散张量成像(DTI)在腰椎间盘退行性变评估中的应用价值。方法 选择100例腰椎间盘退行性变患者,其中男性51例,女性49例;年龄14~85岁,平均年龄49.4岁;病程1天~3年,平均病程(65.0±16.2)天;发生椎间盘突出部位L_(1/2)椎间盘2例,L_(2/3)椎间盘7例,L_(3/4)椎间盘23例,L_(4/5)椎间盘56例,L5/S1椎间盘48例。采用T_(2)WI IDEAL水相位图根据Pfirrmann分级标准对椎间盘进行分级,并测量各椎间盘T_(2)信号强度(T_(2)SI)。采用矢状位DTI图测量各椎间盘部分各向异性系数(FA)及表观扩散系数(ADC)。比较椎间盘不同Pfirrmann分级间FA、ADC值及T_(2)SI,并统计分析FA、ADC值及T_(2)SI与Pfirrmann分级间的相关性。结果 腰腿痛患者中,Ⅰ级椎间盘19个,Ⅱ级椎间盘126个,Ⅲ级椎间盘178个,Ⅳ级椎间盘144个,Ⅴ级椎间盘33个。椎间盘不同Pfirrmann分级间FA、ADC值及T_(2)SI总体差异均具有统计学意义(P<0.05)。组间多重比较显示,椎间盘ADC值在Ⅳ级与Ⅴ级之间差异无统计学意义(P>0.05),Ⅰ~Ⅲ级组间差异有统计学意义(P<0.05);FA及T_(2)SI组间比较,除Ⅰ级与Ⅱ级间差异无统计学意义(P>0.05)外,其余Ⅲ~Ⅴ级组间差异均有统计学意义(P<0.05)。椎间盘FA值与Pfirrmann分级呈中度正相关(r=0.626,P<0.05);ADC值与Pfirrmann分级呈高度负相关(r=-0.752,P<0.05);T_(2)SI与Pfirrmann分级呈高度负相关(r=-0.712,P<0.05);T_(2)SI与ADC值呈中度正相关(r=0.505,P<0.05);T_(2)SI与FA值呈弱负相关(r=-0.319,P<0.05)。结论 结合T_(2)WI IDEAL和DTI进行分析,可以为腰椎间盘退行性变的临床诊断及疗效评估提供参考依据。 展开更多
关键词 磁共振成像 椎间盘退行性变 ideal序列 扩散张量成像
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