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Real-time reconstruction and discrimination of pile-up neutron and gamma signals via bipolar cusp-like pulse shaping in NaIL scintillators
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作者 Jia-Xin Li Hui-Liang Hou +1 位作者 Yue-Feng Huang Zhi-Min Dai 《Nuclear Science and Techniques》 2026年第3期90-104,共15页
At high count rates,pile-up events involving neutron and gamma signals result in inaccurate neutron counting and distortions in the energy spectrum.Additionally,a bipolar cusp-like pulse shaping algorithm based on an ... At high count rates,pile-up events involving neutron and gamma signals result in inaccurate neutron counting and distortions in the energy spectrum.Additionally,a bipolar cusp-like pulse shaping algorithm based on an unfolding synthesis technique was proposed.This algorithm exhibits a narrow pulse shape,and the parallel design of the dual algorithms enables the recovery of pile-up signal amplitudes while preserving the distinct characteristics of neutron and gamma signals.The simplicity of the algorithm facilitates real-time neutron/gamma discrimination on an FPGA,allowing the energy spectra to be updated with each incoming signal.Furthermore,the algorithm can be readily tailored to various experimental conditions by adjusting the decay time constants.Multi-objective optimization reduces the need for manual parameter tuning by rapidly identifying the optimal parameters.Testing with a^(241)Am-Be neutron source and a NaIL scintillator yielded a figure of merit(FoM)value of 2.11 and produced a clear energy spectrum even at high count rates. 展开更多
关键词 FPGA PILE-UP Neutron/gamma discrimination NAIL Multi-objective optimization
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The Influence of Discrimination Perception on the Psychological Resilience among Vocational High School Students:Longitudinal Mediating Effect of Vocational Identity
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作者 Lingyan Zhang Yuying Yang Zhuoxuan Huang 《International Journal of Mental Health Promotion》 2026年第2期112-124,共13页
Objectives:Psychological resilience is a critical resource for vocational high school students navigating social biases and fostering mental well-being.This six-month longitudinal study investigated the developmental ... Objectives:Psychological resilience is a critical resource for vocational high school students navigating social biases and fostering mental well-being.This six-month longitudinal study investigated the developmental trajectories of discrimination perception,vocational identity,and psychological resilience in this population.It further examined the longitudinal mediating role of vocational identity in the relationship between discrimination perception and psychological resilience.Methods:A total of 526 students from five vocational high schools in Guangdong,China,were assessed via convenience sampling at two time points:baseline(T1,September 2023)and six-month follow-up(T2,March 2024).Measures of discrimination perception,psychological resilience,and vocational identity were administered.Data were analyzed using a cross-lagged panel model to test for bidirectional relationships.Results:Over the six-month period,students showed significant decreases in discrimination perception and vocational identity,but a significant increase in psychological resilience.The cross-lagged model revealed significant bidirectional relationships:discrimination perception and psychological resilience negatively predicted each other over time(β=−0.124,p<0.01;β=−0.200,p<0.001),while psychological resilience and vocational identity positively predicted each other(β=0.084,p<0.05;β=0.076,p<0.05).The mediation analysis revealed a dual-pathway mechanism.T1 discrimination perception exerted both a significant direct negative effect on T2 psychological resilience(β=−0.332,p<0.001)and a significant indirect positive effect via T1 vocational identity(indirect effect=0.020,95%CI[0.001,0.046]).This confirms a partial mediating role,indicating that vocational identity functions as a compensatory mechanism,transforming the experience of discrimination perception into a potential source of psychological resilience.Conclusions:For vocational high school students,perception of discrimination directly undermines psychological resilience,but also indirectly fosters it through the positive development of vocational identity.These findings highlight vocational identity as a pivotal mechanism in the complex relationship between social adversity and mental resilience. 展开更多
关键词 Vocational high school students vocational identity discrimination perception psychological resilience
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Disparity in immigrant compulsory care assignment: discrimination or response to treatment need
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作者 Steven P Segal Leena Badran +1 位作者 Lachlan Rimes Vinay Lakra 《General Psychiatry》 2025年第3期234-241,共8页
INTRODUCTION Reports indicating that culturally and linguistically diverse(CALD)people-often with migrant backgrounds-in Australia and New Zealand are more likely to be placed in compulsory community treatment(CCT)hav... INTRODUCTION Reports indicating that culturally and linguistically diverse(CALD)people-often with migrant backgrounds-in Australia and New Zealand are more likely to be placed in compulsory community treatment(CCT)have rightlyraised concernsthat such action might be discriminatory. 展开更多
关键词 NEED compulsory community treatment cct DISPARITY response IMMIGRANT ASSIGNMENT discrimination compulsory care
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Optical transmittance and pulse shape discrimination of polystyrene/poly(methyl methacrylate)-based plastic scintillators
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作者 Yi-Yao Liang Ying-Du Liu +2 位作者 Pu-Sen Wang Jie Bao Xiao-Ping Ouyang 《Nuclear Science and Techniques》 2025年第1期94-102,共9页
Polymethyl methacrylate(PMMA)is an optically transparent thermoplastic with favorable processing conditions.In this study,a series of plastic scintillators are prepared via thermal polymerization,and the impact of PMM... Polymethyl methacrylate(PMMA)is an optically transparent thermoplastic with favorable processing conditions.In this study,a series of plastic scintillators are prepared via thermal polymerization,and the impact of PMMA content on their transparency and pulse shape discrimination(PSD)ability is investigated.The fabricated samples,comprising a polystyrene(PS)-PMMA matrix,30.0 wt%2,5-diphenyloxazole(PPO),and 0.2 wt%9,10-diphenylanthracene(DPA),exhibit high transparency with transmissivity ranging from 70.0 to 90.0%(above 415.0 nm)and demonstrate excellent n/γdiscrimination capability.Transparency increased with increasing PMMA content across the entire visible light spectrum.However,the PSD performance gradually deteriorated when the aromatic matrix was replaced with PMMA.The scintillator containing 20.0 wt%PMMA demonstrated the best stability concerning PSD properties and relative light yields. 展开更多
关键词 Neutron detection Plastic scintillation Pulse shape discrimination Polymethyl-methacrylate POLYSTYRENE
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Brain White Matter Changes in Non-demented Individuals with Color Discrimination Deficits and Their Association with Cognitive Impairment:A NODDI Study
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作者 Jiejun Zhang Peilin Huang +6 位作者 Lin Lin Yingzhe Cheng Weipin Weng Jiahao Zheng Yixin Sun Shaofan Jiang Xiaodong Pan 《Neuroscience Bulletin》 2025年第8期1364-1376,共13页
Previous studies have found associations between color discrimination deficits and cognitive impairments besides aging.However,investigations into the microstructural pathology of brain white matter(WM)associated with... Previous studies have found associations between color discrimination deficits and cognitive impairments besides aging.However,investigations into the microstructural pathology of brain white matter(WM)associated with these deficits remain limited.This study aimed to examine the microstructural characteristics of WM in the non-demented population with abnormal color discrimination,utilizing Neurite Orientation Dispersion and Density Imaging(NODDI),and to explore their correlations with cognitive functions and cognition-related plasma biomarkers.The tract-based spatial statistic analysis revealed significant differences in specific brain regions between the abnormal color discrimination group and the healthy controls,characterized by increased isotropic volume fraction and decreased neurite density index and orientation dispersion index.Further analysis of region-of-interest parameters revealed that the isotropic volume fraction in the bilateral anterior thalamic radiation,superior longitudinal fasciculus,cingulum,and forceps minor was significantly correlated with poorer performance on neuropsychological assessments and to varying degrees various cognition-related plasma biomarkers.These findings provide neuroimaging evidence that WM microstructural abnormalities in non-demented individuals with abnormal color discrimination are associated with cognitive dysfunction,potentially serving as early markers for cognitive decline. 展开更多
关键词 NODDI Color discrimination COGNITION White matter microstructure Non-demented population
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An intelligent sensing platform for discrimination of formaldehyde and nitrite in food
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作者 Huan Ye Ying Yang +3 位作者 Lirong Jiang Taotao Zhe Junchao Xu Lintao Zeng 《Chinese Chemical Letters》 2025年第11期407-413,共7页
Formaldehyde(FA)and excessive nitrite(NO_(2)^(-))are highly carcinogenic compounds that pose serious risks to human health.In this study,we designed a sensing platform 8-hydrazine-boron dipyrromethene(OPTY)for the det... Formaldehyde(FA)and excessive nitrite(NO_(2)^(-))are highly carcinogenic compounds that pose serious risks to human health.In this study,we designed a sensing platform 8-hydrazine-boron dipyrromethene(OPTY)for the detection of FA and nitrite in food.Upon aldimine condensation with FA,OPTY produced strong blue fluorescence.By contrast,NO_(2)^(-)underwent an intramolecular cyclization cascade reaction with OPTY to boast bright green fluorescence.OPTY has the advantages of high signal-to-noise ratio,good selectivity,and a low limit of detection(LOD=26.5 nmol/L for FA,LOD=20.8 nmol/L for NO_(2)^(-)).Furthermore,OPTY was fabricated into a portable sensing chip,which was combined with smartphone to form a portable sensing platform.This platform has been successfully applied for the determination of FA/NO_(2)^(-)in meat and seafood with high accuracy(93.49%-102.35%).Therefore,the intelligent sensing platform can realize on-site visual detection of FA/NO_(2)^(-)content in food,demonstrating great potential for ensuring food safety. 展开更多
关键词 Fluorescent probe FORMALDEHYDE NITRITE discrimination detection Intelligent sensing platform
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Applications of Deep Learning in Mineral Discrimination:A Case Study of Quartz,Biotite and K-Feldspar from Granite
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作者 Wei Lou Dexian Zhang 《Journal of Earth Science》 2025年第1期29-45,共17页
Mineral identification and discrimination play a significant role in geological study.Intelligent mineral discrimination based on deep learning has the advantages of automation,low cost,less time consuming and low err... Mineral identification and discrimination play a significant role in geological study.Intelligent mineral discrimination based on deep learning has the advantages of automation,low cost,less time consuming and low error rate.In this article,characteristics of quartz,biotite and Kfeldspar from granite thin sections under cross-polarized light were studied for mineral images intelligent classification by Inception-v3 deep learning convolutional neural network(CNN),and transfer learning method.Dynamic images from multi-angles were employed to enhance the accuracy and reproducibility in the process of mineral discrimination.Test results show that the average discrimination accuracies of quartz,biotite and K-feldspar are 100.00%,96.88%and 90.63%.Results of this study prove the feasibility and reliability of the application of convolution neural network in mineral images classification.This study could have a significant impact in explorations of complicated mineral intelligent discrimination using deep learning methods and it will provide a new perspective for the development of more professional and practical mineral intelligent discrimination tools. 展开更多
关键词 deep learning mineral discrimination Inception-v3 CNN transfer learning convolutional neural network
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FDCPNet:feature discrimination and context propagation network for 3D shape representation
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作者 Weimin SHI Yuan XIONG +2 位作者 Qianwen WANG Han JIANG Zhong ZHOU 《虚拟现实与智能硬件(中英文)》 2025年第1期83-94,共12页
Background Three-dimensional(3D)shape representation using mesh data is essential in various applications,such as virtual reality and simulation technologies.Current methods for extracting features from mesh edges or ... Background Three-dimensional(3D)shape representation using mesh data is essential in various applications,such as virtual reality and simulation technologies.Current methods for extracting features from mesh edges or faces struggle with complex 3D models because edge-based approaches miss global contexts and face-based methods overlook variations in adjacent areas,which affects the overall precision.To address these issues,we propose the Feature Discrimination and Context Propagation Network(FDCPNet),which is a novel approach that synergistically integrates local and global features in mesh datasets.Methods FDCPNet is composed of two modules:(1)the Feature Discrimination Module,which employs an attention mechanism to enhance the identification of key local features,and(2)the Context Propagation Module,which enriches key local features by integrating global contextual information,thereby facilitating a more detailed and comprehensive representation of crucial areas within the mesh model.Results Experiments on popular datasets validated the effectiveness of FDCPNet,showing an improvement in the classification accuracy over the baseline MeshNet.Furthermore,even with reduced mesh face numbers and limited training data,FDCPNet achieved promising results,demonstrating its robustness in scenarios of variable complexity. 展开更多
关键词 3D shape representation Mesh model MeshNet Feature discrimination Context propagation
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Comprehensive study of pulse shape discrimination in a Ga-doped zinc oxide scintillating detector
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作者 Kuo Zhao Liang Chen +5 位作者 Ning Lv Lei-Dang Zhou Shi-Yi He Jin-Lu Ruan Han Wang Xiao-Ping Ouyang 《Nuclear Science and Techniques》 2025年第3期38-49,共12页
Doping with Ga effectively enhances the crystal quality and optical detection efficiency of zinc oxide(Zn O)single crystals,which has attracted considerable research interest in radiation detection.The application of ... Doping with Ga effectively enhances the crystal quality and optical detection efficiency of zinc oxide(Zn O)single crystals,which has attracted considerable research interest in radiation detection.The application of Zn O:Ga(GZO)in nuclear energy is particularly significant and fascinating at the fundamental level,enabling neutron/gamma discrimination while preserving the response time properties of the single crystal in sub-nanoseconds,maximizing the effective counting rate of the pulsed radiation field.In this study,the single-particle waveform discrimination characteristics of GZO were evaluated for five charged particles(α,β,H^(+),Li^(+),and O^(8+)and two prevalent uncharged particles(neutrons and gamma rays).Based on the timecorrelation single-photon counting(TCSPC)method,the luminescence decay time constants of the charged particles in the GZO crystal were determined as follows:1.21 ns for H^(+),1.50 ns for Li^(+),1.70 ns for O^(8+),1.56 ns forαparticles,and 1.09 ns forβparticles.Visible differences in the excitation time spectra curves were observed.Using the conventional time-domain or frequency-domain waveform discrimination techniques,waveform discrimination of 14.9 Me V neutrons and secondary gamma rays generated by the CPNG-6 device based on GZO scintillation was successfully implemented.The neutron signal constituted 77.93%of the total,indicating that GZO exhibited superior neutron/gamma discrimination sensitivity compared with that of a commercial stilbene crystal.Using the neutron/gamma screening outcomes,we reconstructed the voltage pulse height,charge height,and neutron multiplication time spectra of the pulsed neutron radiation field.The reconstructed neutron multiplication time spectrum exhibited a deviation of less than 3%relative to the result obtained using a commercial stilbene scintillator.This is the first report in the open literature on the neutron/gamma discrimination and reconstruction of Zn O pulsed radiation-field information. 展开更多
关键词 Zinc oxide Scintillation crystal Pulse shape discrimination Radiation luminescence Pulsed neutron radiation field
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Sampling complexity of quantum channel discrimination
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作者 Lei Li Zhe Ji +2 位作者 Qing-Wen Wang Shu-Qian Shen Ming Li 《Communications in Theoretical Physics》 2025年第10期85-95,共11页
In this paper,we study the problem of sampling complexity for channel discrimination with respect to two different strategies:product strategy and adaptive strategy.We first formally introduce the definitions of the s... In this paper,we study the problem of sampling complexity for channel discrimination with respect to two different strategies:product strategy and adaptive strategy.We first formally introduce the definitions of the sampling complexity of the channels under the framework of hypothesis testing,wherein the goal is to determine the minimum number of samples needed to reach a desired error probability.We then establish the lower and upper bounds on the sampling complexity of the symmetric,asymmetric,and error exponent hypothesis testing settings.We show that,by imposing product strategy on testing,the bounds are always characterized by the generalized channel divergence,while with adaptive strategy,the bounds are characterized by the amortized channel divergence.Finally,we analyze two concrete examples,and obtain that the adaptive strategy can not lead to an advantage to the problem of determining the sampling complexity for classical-quantum channels,which can bring advantages for generalized amplitude damping channels. 展开更多
关键词 quantum channel adaptive strategy quantum discrimination quantum complexity
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Weak feedback self-mixing interference fringe slope discrimination method based on deep learning
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作者 ZHAO Yan LIN Maohua +3 位作者 DU Shengzhi TONG Jigang LIU Bin HAN Fangfang 《Optoelectronics Letters》 2025年第11期684-689,共6页
In order to identify the tilt direction of the self-mixing signals under weak feedback regime interfered by noise,a deep learning method is proposed.The one-dimensional U-Net(1D U-Net)neural network can identify the d... In order to identify the tilt direction of the self-mixing signals under weak feedback regime interfered by noise,a deep learning method is proposed.The one-dimensional U-Net(1D U-Net)neural network can identify the direction of the self-mixing fringes accurately and quickly.In the process of measurement,the measurement signal can be normalized and then the neural network can be used to discriminate the direction.Simulation and experimental results show that the proposed method is suitable for self-mixing interference signals with noise in the whole weak feedback regime,and can maintain a high discrimination accuracy for signals interfered by 5 dB large noise.Combined with fringe counting method,accurate and rapid displacement reconstruction can be realized. 展开更多
关键词 weak feedback identify direction measurement signal DISCRIMINATE self mixing interference weak feedback regime neural network identify tilt direction
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Saturation correction and effi cient discrimination methods for low-resistivity sandstone oil reservoirs
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作者 Jin Li-zuan 《Applied Geophysics》 2025年第2期319-330,556,共13页
This study discusses the challenges in logging the evaluation of low-resistivity oil reservoirs,especially the difficult problems involving their saturation calculation.A correction method for equivalent water conduct... This study discusses the challenges in logging the evaluation of low-resistivity oil reservoirs,especially the difficult problems involving their saturation calculation.A correction method for equivalent water conductivity is proposed,given the high conductivity caused by small amounts of water distributed in a network within the low-resistivity reservoir,which mimics the eff ects of high water saturation.This approach signifi cantly improves the accuracy of hydrocarbon saturation calculations in these low-resistivity reservoirs.The corrected hydrocarbon saturation values highly matched the porosity and are consistent with experimental results.This study also establishes a discrimination process to determine whether corrections are required,verifying the eff ectiveness and accuracy of the method through an application example. 展开更多
关键词 low-resistivity oil reservoirs saturation correction equivalent water conductivity discriminant methods
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浅海声源深度判决的正交子空间方法
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作者 王燕 朱文博 +2 位作者 王晋晋 邹男 梁国龙 《声学学报》 北大核心 2026年第1期110-118,共9页
针对浅水环境中的水面水下目标分辨问题,提出一种基于正交子空间的深度判决方法。通过凸优化方法对陷波子空间进行预处理,以去除干扰项提高子空间能量的估计精度。使用Schimidt正交构建正交的陷波分量和自由分量子空间,保留了完整的模... 针对浅水环境中的水面水下目标分辨问题,提出一种基于正交子空间的深度判决方法。通过凸优化方法对陷波子空间进行预处理,以去除干扰项提高子空间能量的估计精度。使用Schimidt正交构建正交的陷波分量和自由分量子空间,保留了完整的模态空间以增加参与判决的模态信息。通过仿真分析了信噪比和垂直孔径对各方法性能的影响,结果表明所提方法在阵列垂直孔径较小时的深度判决性能优于作为对比方法的匹配子空间判决器和基于正则最小二乘的模态滤波器。最后,利用浅海实验获得的数据对该方法进行了验证。数据结果表明,信噪比为7~16 dB时,在阵列孔径为0.16倍环境水深的情况下,所提方法仍可实现对水面和水下目标的分辨,正确分辨率高于对比方法。 展开更多
关键词 声源深度判决 正交子空间 Schimidt正交 模态空间
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迈向算法正义:算法歧视的社会建构及其治理策略
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作者 毛俊响 郭敏 《中南大学学报(社会科学版)》 北大核心 2026年第1期32-47,共16页
算法作为一种社会存在,与社会结构相互作用。算法歧视是社会建构的结果,社会歧视的历史承继、算法运行的修正障碍、价值偏好的隐性渗透、社会生态的利益导向,共同作用于算法歧视。算法歧视并非算法内生技术性问题衍生的新形式不平等,而... 算法作为一种社会存在,与社会结构相互作用。算法歧视是社会建构的结果,社会歧视的历史承继、算法运行的修正障碍、价值偏好的隐性渗透、社会生态的利益导向,共同作用于算法歧视。算法歧视并非算法内生技术性问题衍生的新形式不平等,而是历史与现实问题在算法时代的映射。算法歧视从财富、权力、声望三个方面阻碍合理化社会流动,加剧了社会结构失衡。为此,需要建构算法正义来实现对算法歧视的纠正。建构算法正义,需要回应分配正义与关系正义的双重要求,将受保护特征纳入算法决策,尊重群体多元、避免多样性“武器化”,正视基于群体差异的特殊优待并提升少数群体的算法决策话语权。实现算法正义,应采用技术、法律、伦理三元协同治理模式,重点是设计以算法区分为中心的法律规制模式,布局以“科技向善”为核心的人工智能全周期治理机制。 展开更多
关键词 算法歧视 算法正义 算法区分 算法治理
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颜色识别式人工智能融入混合碱滴定实验的应用
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作者 王月娇 毛全兴 +4 位作者 崔俊硕 冯小庚 常晓红 娄振宁 熊英 《大学化学》 2026年第1期107-113,共7页
在混合碱滴定分析实验中,存在第一化学计量点终点判读主观性强、三次平行测定误差大的缺点。本文利用颜色识别式人工智能(CDAI)进行终点判断,通过硬件精确控制与智能算法相结合,建立客观、可量化的酚酞和甲基橙的动态颜色判别模型,有效... 在混合碱滴定分析实验中,存在第一化学计量点终点判读主观性强、三次平行测定误差大的缺点。本文利用颜色识别式人工智能(CDAI)进行终点判断,通过硬件精确控制与智能算法相结合,建立客观、可量化的酚酞和甲基橙的动态颜色判别模型,有效解决了终点判读及重现性差问题。本文探索并实践了一种新型智能化的滴定实验方法,为化学实验教学的数字化转型提供了可推广的实践方案。 展开更多
关键词 混合碱 滴定 PYTHON 人工智能 颜色识别
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基于多模态语义信息的文本生成图像方法
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作者 杨冰 周家辉 +1 位作者 姚金良 向学勤 《浙江大学学报(工学版)》 北大核心 2026年第2期360-369,共10页
针对文本语义与图像语义不一致以及图像细节表现不足的问题,提出新的文本生成图像方法.基于多模态语义信息建立鉴别依据,在文本语义基础上引入真实图像语义,以解决文本描述信息密度低的问题,有效缓解生成图像细节缺失或失真的现象.在生... 针对文本语义与图像语义不一致以及图像细节表现不足的问题,提出新的文本生成图像方法.基于多模态语义信息建立鉴别依据,在文本语义基础上引入真实图像语义,以解决文本描述信息密度低的问题,有效缓解生成图像细节缺失或失真的现象.在生成器中集成可变形卷积和星模块卷积,增强生成器表达能力,提高生成图像的细节表现和整体质量.为了验证所提方法的有效性,在CUB数据集和COCO数据集上进行模型训练及评估.与生成式对抗对比语言-图像预训练模型(GALIP)相比,所提方法在保证高效生成的同时,在细节表现、语义一致性及整体质量上具有显著优势. 展开更多
关键词 文本生成图像 多模态语义 可变形卷积 星模块卷积 语义对齐鉴别器
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促进家庭:生育支持的基本理念与制度构造
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作者 蔡琳 《浙江社会科学》 北大核心 2026年第1期59-70,157,158,共14页
生育支持政策需要立足生育本身的阶段性困境,理解其蕴含的伦理价值,进而探寻生育支持的基本理念并推进制度构建。生育面临三重困境:“母职”的非市场化、依赖关系和脆弱性、育儿策略的代际向上偏好。家庭主义的生育支持政策肯定婚姻家... 生育支持政策需要立足生育本身的阶段性困境,理解其蕴含的伦理价值,进而探寻生育支持的基本理念并推进制度构建。生育面临三重困境:“母职”的非市场化、依赖关系和脆弱性、育儿策略的代际向上偏好。家庭主义的生育支持政策肯定婚姻家庭的道德意义,主张促进社会团结并进而实现生育正义,其内容主要包括反生育歧视的制度设计以及促进性别平等的抚育政策。 展开更多
关键词 生育支持 家庭主义 社会团结 反生育歧视 性别平等
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人工智能技术在学业诊断模型构建中的应用——以高等数学课程为例
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作者 黄利文 张纪平 +1 位作者 董会英 傅瑞瑜 《中国现代教育装备》 2026年第3期38-41,共4页
本文在分析常见习题设计思路和学业评价存在不足的基础上,构建数据分析的观测指标体系;基于收集的学生成绩数据,按观测指标整理样本数据;采用Fisher线性判别法分析样本数据、实施学业诊断。通过三种方案对模型的稳定性开展测试诊断。实... 本文在分析常见习题设计思路和学业评价存在不足的基础上,构建数据分析的观测指标体系;基于收集的学生成绩数据,按观测指标整理样本数据;采用Fisher线性判别法分析样本数据、实施学业诊断。通过三种方案对模型的稳定性开展测试诊断。实例结果表明,构建的学业诊断模型具有较高的正确率,能根据学生成绩给出参考的学业水平和相应的学习建议。 展开更多
关键词 人工智能 FISHER线性判别 学业诊断 智能分析
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基于光谱特征选择和机器学习的沥青类型识别
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作者 吕悦晶 钱进 +3 位作者 刘渭宁 汤文 王进波 薛永康 《江苏大学学报(自然科学版)》 北大核心 2026年第1期104-110,124,共8页
为提高识别速率,采用傅里叶变换红外光谱(FTIR)结合机器学习技术对多种老化状态下沥青的类型与等级进行分析.首先基于衰减全反射红外光谱(ATR-FTIR)对多种老化状态下的72个沥青样本进行光谱特征提取,分别采用连续投影算法(SPA)、主成分... 为提高识别速率,采用傅里叶变换红外光谱(FTIR)结合机器学习技术对多种老化状态下沥青的类型与等级进行分析.首先基于衰减全反射红外光谱(ATR-FTIR)对多种老化状态下的72个沥青样本进行光谱特征提取,分别采用连续投影算法(SPA)、主成分分析(PCA)、特征峰吸光度分析对沥青光谱样本进行特征提取,并简化光谱数据;其次将上述光谱数据作为输入数据,分别采用支持向量机(SVM)和线性判别分析(LDA)建立分类模型;最后采用交叉验证和混淆矩阵进行模型评价.结果表明:基于光谱特征选择(SPA、PCA、特征峰吸光度)与LDA的组合模型,对沥青老化状态进行分类识别,识别准确率达到100%,交叉验证准确率超过98%;光谱特征提取与LDA的组合模型显著提高了泛化能力与分类准确性,能够有效区分多种老化状态下的沥青种类及其服役状态. 展开更多
关键词 沥青分类 红外光谱 光谱特征选择 支持向量机 线性判别分析 机器学习
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Response of Photosynthesis, Growth, Carbon Isotope Discrimination and Osmotic Tolerance of Rice to Elevated CO_2 被引量:3
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作者 彭长连 段俊 +2 位作者 林桂珠 陈贻竹 彭少麟 《Acta Botanica Sinica》 CSCD 2002年第1期76-81,共6页
Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 conc... Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 concentration which was controlled by computer. As compared with rice at ambient 35 μmol/mol CO 2, the changes in photosynthetic rate at elevated CO 2 showed up_regulation ('IR72' and 'Tesanai 2'), stable (unchanged) in 'Guichao 2' and down_regulation type ('IIyou 4480'). Growth rate, panicle weight, integrated water use efficiency (WUE) calculated from Δ 13 C and the capacity of scavenging DPPH · (1,1_diphenyl_2_picrylhydrazyl) free radical were increased at elevated CO 2. An increment in total biomass was observed in three cultivars by elevated CO 2, with the exception of 'IIyou 4480'. Ratios of panicle weight/total biomass were altered to different extents in tested cultivars by elevated CO 2. When leaf segments were subjected to PEG osmotic stress, the electrolyte leakage rate from leaves grown at elevated CO 2 was less than that at 35 μmol/mol CO 2. Those intraspecific variations of rice imply a possibility for selecting cultivars with maximal productivity and high tolerance to stresses adapted to elevated CO 2 in the future. 展开更多
关键词 rice cultivars elevated CO 2 PHOTOSYNTHESIS water use efficiency 13 C discrimination osmotic tolerance
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