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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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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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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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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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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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Friend or foe? Using eye-tracking technology to investigate the visual discrimination ability of giant pandas
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作者 Xinrui Huang Guo Li +9 位作者 Guiquan Zhang Zixiang Li Lin Zhao Mengdie Zhu Qinghua Xiang Xuefeng Liu Mei Tian Hemin Zhang Christina D.Buesching Dingzhen Liu 《Current Zoology》 SCIE CAS CSCD 2024年第4期430-439,共10页
The role that visual discriminative ability plays among giant pandas in social communication and individual discrimination has received less attention than olfactory and auditory modalities.Here,we used an eye-tracker... The role that visual discriminative ability plays among giant pandas in social communication and individual discrimination has received less attention than olfactory and auditory modalities.Here,we used an eye-tracker technology to investigate pupil fixation patterns for 8 captive male giant pandas Ailuropoda melanoleuca.We paired images(N=26)of conspecifics against:1)sympatric predators(gray wolves and tigers),and non-threatening sympatric species(golden pheasant,golden snub-nosed monkey,takin,and red panda),2)conspecifics with atypical fur colora-tion(albino and brown),and 3)zookeepers/non-zookeepers wearing either work uniform or plain clothing.For each session,we tracked the pan-da's pupil movements and measured pupil first fixation point(FFP),fixation latency,total fixation count(TFC),and duration(TFD)of attention to each image.Overall,pandas exhibited similar attention(FFPs and TFCs)to images of predators and non-threatening sympatric species.Images of golden pheasant,snub-nosed monkey,and tiger received less attention(TFD)than images of conspecifics,whereas images of takin and red panda received more attention,suggesting a greater alertness to habitat or food competitors than to potential predators.Pandas'TFCs were greater for images of black-white conspecifics than for albino or brown phenotypes,implying that familiar color elicited more interest.Pandas reacted differently to images of men versus women.For images of women only,pandas gave more attention(TFC)to familiar combinations(uniformed zookeepers and plain-clothed non-zookeepers),consistent with the familiarity hypothesis.That pandas can use visual perception to discriminate intra-specifically and inter-specifically,including details of human appearance,has applications for panda conservation and captive husbandry. 展开更多
关键词 eye movement tracker giant panda images total fixation duration total pupil fixation count visual discrimination.
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LociScan,a tool for screening genetic marker combinations for plant variety discrimination 被引量:1
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作者 Yang Yang Hongli Tian +5 位作者 Hongmei Yi Zi Shi Lu Wang Yaming Fan Fengge Wang Jiuran Zhao 《The Crop Journal》 SCIE CSCD 2024年第2期583-593,共11页
To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening m... To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening model based on the genetic algorithm(GA)and implemented in a software tool,Loci Scan.Ratio-based variety discrimination power provided the largest optimization space among multiple fitness functions.Among GA parameters,an increase in population size and generation number enlarged optimization depth but also calculation workload.Exhaustive algorithm afforded the same optimization depth as GA but vastly increased calculation time.In comparison with two other software tools,Loci Scan accommodated missing data,reduced calculation time,and offered more fitness functions.In large datasets,the sample size of training data exerted the strongest influence on calculation time,whereas the marker size of training data showed no effect,and target marker number had limited effect on analysis speed. 展开更多
关键词 Plant variety discrimination Genetic marker combination Variety discrimination power Genetic algorithm
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The Analysis of the Correlation between SPT and CPT Based on CNN-GA and Liquefaction Discrimination Research 被引量:1
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作者 Ruihan Bai Feng Shen +2 位作者 Zihao Zhao Zhiping Zhang Qisi Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1159-1182,共24页
The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires f... The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires field testing and canbe time-consuming and labor-intensive. In contrast, the cone penetration test (CPT) provides a more convenientmethod and offers detailed and continuous information about soil layers. In this study, the feature matrix based onCPT data is proposed to predict the standard penetration test blow count N. The featurematrix comprises the CPTcharacteristic parameters at specific depths, such as tip resistance qc, sleeve resistance f s, and depth H. To fuse thefeatures on the matrix, the convolutional neural network (CNN) is employed for feature extraction. Additionally,Genetic Algorithm (GA) is utilized to obtain the best combination of convolutional kernels and the number ofneurons. The study evaluated the robustness of the proposed model using multiple engineering field data sets.Results demonstrated that the proposed model outperformed conventional methods in predicting N values forvarious soil categories, including sandy silt, silty sand, and clayey silt. Finally, the proposed model was employedfor liquefaction discrimination. The liquefaction discrimination based on the predicted N values was comparedwith the measured N values, and the results showed that the discrimination results were in 75% agreement. Thestudy has important practical application value for foundation liquefaction engineering. Also, the novel methodadopted in this research provides new ideas and methods for research in related fields, which is of great academicsignificance. 展开更多
关键词 CNN liquefaction discrimination SPT CPT
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Skmer approach improves species discrimination in taxonomically problematic genus Schima(Theaceae)
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作者 Han-Ning Duan Yin-Zi Jiang +4 位作者 Jun-Bo Yang Jie Cai Jian-Li Zhao Lu Li Xiang-Qin Yu 《Plant Diversity》 SCIE CAS CSCD 2024年第6期713-722,共10页
Genome skimming has dramatically extended DNA barcoding from short DNA fragments to next generation barcodes in plants.However,conserved DNA barcoding markers,including complete plastid genome and nuclear ribosomal DN... Genome skimming has dramatically extended DNA barcoding from short DNA fragments to next generation barcodes in plants.However,conserved DNA barcoding markers,including complete plastid genome and nuclear ribosomal DNA(nrDNA)sequences,are inadequate for accurate species identification.Skmer,a recently proposed approach that estimates genetic distances among species based on unassembled genome skims,has been proposed to effectively improve species discrimination rate.In this study,we used Skmer to identify species based on genomic skims of 47 individuals representing 10 out of 13 species of Schima(Theaceae)from China.The unassembled reads identified six species,with a species identification rate of 60%,twice as high as previous efforts that used plastid genomes(27.27%).In addition,Skmer was able to identify Schima species with only 0.5sequencing depth,as six species were well-supported with unassembled data sizes as small as 0.5 Gb.These findings demonstrate the potential for Skmer approach in species identification,where nuclear genomic data plays a crucial role.For taxonomically difficult taxa such as Schima,which have diverged recently and have low levels of genetic variation,Skmer is a promising alternative to next generation barcodes. 展开更多
关键词 SCHIMA Genome skimming Species discrimination Skmer
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FPGA implementation of 500-MHz high-count-rate high-time-resolution real-time digital neutron-gamma discrimination for fast liquid detectors
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作者 Hui‑Yin Shen Jing‑Long Zhang +1 位作者 Jie Zhang Jian‑Hang Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期101-113,共13页
Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a sel... Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a self-developed 500-Msps,12-bit digitizer,and the neutron and gamma spectra were calculated directly on an FPGA.A fast neutron flux measurement system with BC-501A and EJ-309 liquid scintillator detectors was developed and a fast neutron measurement experiment was successfully performed on the HL-2 M tokamak at the Southwestern Institute of Physics,China.The experimental results demonstrated that the system obtained the neutron and gamma spectra with a time accuracy of 1 ms.At count rates of up to 1 Mcps,the figure of merit was greater than 1.05 for energies between 50 keV and 2.8 MeV. 展开更多
关键词 Neutron-gamma discrimination Liquid scintillation detector Real-time spectrum analyzer
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Balancing the minimum error rate and minimum copy consumption in quantum state discrimination
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作者 Boxuan Tian Zhibo Hou +2 位作者 Guo-Yong Xiang Chuan-Feng Li Guang-Can Guo 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期40-42,39,I0002,I0003,共6页
Extracting more information and saving quantum resources are two main aims for quantum measurements.However,the optimization of strategies for these two objectives varies when discriminating between quantum states |ψ... Extracting more information and saving quantum resources are two main aims for quantum measurements.However,the optimization of strategies for these two objectives varies when discriminating between quantum states |ψ_(0)> and |ψ_(1)> through multiple measurements.In this study,we introduce a novel state discrimination model that reveals the intricate relationship between the average error rate and average copy consumption.By integrating these two crucial metrics and minimizing their weighted sum for any given weight value,our research underscores the infeasibility of simultaneously minimizing these metrics through local measurements with one-way communication.Our findings present a compelling trade-off curve,highlighting the advantages of achieving a balance between error rate and copy consumption in quantum discrimination tasks,offering valuable insights into the optimization of quantum resources while ensuring the accuracy of quantum state discrimination. 展开更多
关键词 quantum measurement quantum control quantum state discrimination
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The Influence of Price Discrimination from Airports on the Route Development Behavior of Airlines
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作者 Daniel Schnitzler 《Journal of Civil Engineering and Architecture》 2024年第1期17-29,共13页
Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and t... Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and the route development behavior of airlines is analyzed.Because of rare and often controversial findings in the extant literature regarding relevant influencing variables for attracting airlines at an airport,expert interviews are used as a complement to formulate testable hypotheses in this regard.A fixed effects regression model is used to test the hypotheses with a dataset that covers all seat capacity offered at the 22 largest German commercial airports in the week 46 from 2004 to 2011.It is found that incentives from primary choice,as well as secondary choice airports,have a significant influence on Low Cost Carriers.Furthermore,Low Cost Carriers,in general,do not leave any of both types of airports when the incentives cease.In the case of Network Carriers,no case is found where one joins a primary choice airport and receives an incentive.Insufficient data between Network Carriers and secondary choice airports in the time when incentives have ceased means that no statement can be given. 展开更多
关键词 AIRLINE rout development price discrimination
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基于机器学习的玉米自交系杂种优势类群研究 被引量:3
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作者 曹士亮 张建国 +7 位作者 于滔 杨耿斌 李文跃 马雪娜 孙艳杰 韩微波 唐贵 单大鹏 《中国农业科学》 北大核心 2025年第2期203-213,I0001,I0002,共13页
【目的】优化玉米杂种优势类群划分与判别分析方法,为玉米育种提供指导和参考。【方法】采用固相芯片对60份糯玉米自交系进行基因分型,通过质量控制获得不同密度的SNP标记,采用群体结构分析和遗传距离聚类的方法对60份糯玉米进行类群划... 【目的】优化玉米杂种优势类群划分与判别分析方法,为玉米育种提供指导和参考。【方法】采用固相芯片对60份糯玉米自交系进行基因分型,通过质量控制获得不同密度的SNP标记,采用群体结构分析和遗传距离聚类的方法对60份糯玉米进行类群划分,比较不同密度分子标记和分群方法的差异。在此基础上,分别采用随机森林和支持向量机对类群划分结果进行抽样和交叉验证,比较玉米自交系类群判别的预测精度。【结果】通过不同的质量控制标准分别获得11431和4022个分子标记,基于2种分子标记密度,分别将60份材料分成5个类群和4个类群,其中,以11431个SNP标记为基础,通过群体结构分析和遗传距离聚类结果发现,类群内样本一致性为63.33%,以4022个SNP标记进行分群,发现2种类群划分方法的群内样本一致性为90.00%;比较玉米自交系类群判别的预测精度结果为:基于4022个标记,随机森林和支持向量机预测精度的平均值(91.43%)高于11431个标记的预测精度的平均值(86.25%),其中,预测精度最高的是采用4022个标记的随机森林预测,预测精度为94.17%。【结论】聚类分析法最终将60份玉米糯自交系分为4个类群,运用随机森林和支持向量机对类群划分结果进行抽样和交叉验证,发现随机森林法比支持向量机法能获得更高的预测精度。 展开更多
关键词 玉米 机器学习 交叉验证 类群划分 判别分析
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我国盐碱地治理:现状、问题与展望 被引量:16
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作者 赵耕毛 杨梦圆 +4 位作者 陈硕 苏纪康 吕慧琳 贾慧昕 刘兆普 《南京农业大学学报》 CAS 北大核心 2025年第1期14-26,共13页
随着社会经济快速发展,我国人口、资源、环境的矛盾与日俱增,可持续发展的压力越来越大。与耕地一样,盐碱地作为以盐类集积为主要特征的土地资源,不仅承载着污染净化、生物资源、生物多样性、全球碳库、自然文化遗产、景观旅游等重要功... 随着社会经济快速发展,我国人口、资源、环境的矛盾与日俱增,可持续发展的压力越来越大。与耕地一样,盐碱地作为以盐类集积为主要特征的土地资源,不仅承载着污染净化、生物资源、生物多样性、全球碳库、自然文化遗产、景观旅游等重要功能,也是人类赖以生存的重要农业生产资料。盐碱地治理是以减少作物逆境胁迫、作物健康及其高产优质为主要目标,对于国家粮食安全、生态环境安全、人类健康具有十分重要的意义。近几十年来,历经几代人的努力,我国科技工作者已基本厘清了盐碱地治理理论体系,并建立了符合我国国情的盐碱地治理技术模式。但是,由于盐碱地类型复杂多样,盐碱化程度不同、治理措施多元化等原因,我国尚未建立起分类分区,精准治理,兼顾高水平与低成本的高效治理方法,更没有建立起盐碱地治理及其长效管理的技术与服务体系框架。本文在论述盐碱地概念的基础上,重点介绍盐碱地主要障碍因子、盐碱地治理基本理论与技术方法、盐碱地治理效果判别标准以及盐碱地农业生产的主要模式,阐述盐碱地治理主要问题及展望,以期启发人们对盐碱地的科学认识,强化盐碱地治理技术的应用与实践,结合现代农业新成果,更好地推动盐碱地农业的发展。 展开更多
关键词 盐碱地 治理 粮食安全 障碍因子 技术模式 效果判别
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算法价格歧视违法性认定的挑战与应对 被引量:7
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作者 曾迪 《中国流通经济》 北大核心 2025年第2期115-126,共12页
算法技术在数据收集、分析和应用等方面的优势能够帮助经营者快速实现价格歧视,提高经营效率。但算法价格歧视行为却对市场其他主体带来损害性影响,包括破坏社会对网络市场的公平感知、扭曲市场竞争秩序、侵害消费者知情权等传统权利和... 算法技术在数据收集、分析和应用等方面的优势能够帮助经营者快速实现价格歧视,提高经营效率。但算法价格歧视行为却对市场其他主体带来损害性影响,包括破坏社会对网络市场的公平感知、扭曲市场竞争秩序、侵害消费者知情权等传统权利和个人信息权等新型权益。为避免上述系列损害性后果持续扩散,亟须对司法实践如何开展算法价格歧视违法性认定做出回应。然而,基于我国当前相关法条分布零散且适用性不强、违法性认定规则的合理性和可行性存疑、抗辩理由适用不明等现实困境,司法实务部门在处理算法价格歧视案件时仍面临严峻挑战。原有的经营者滥用市场支配地位认定路径和违规处理个人信息认定路径不能满足现实司法实践所需,有必要从立法和司法层面对算法价格歧视违法性认定的第三条路径予以拓展与优化。在立法完善过程中,《电子商务法》作为我国电商领域的综合性法律,尤其适合作为规制算法价格歧视的法律依据,建议该法新增“不正当价格行为”违法认定类型,明确将保护消费者知情权和选择权不受侵犯设为底线,确立过错推定原则以平衡当事人之间的证明责任。在算法价格歧视违法性认定的司法实践中,坚持行为主体聚焦、侵害客体明晰、主观违背注意义务、客观造成消费者利益受损的“四要件”认定方法。在此基础上,《电子商务法》通过与《反垄断法》《个人信息保护法》等多部法律之间的协同配合,进一步夯实算法价格歧视违法性认定的法律基础,才能共同助力司法实践顺利推进。 展开更多
关键词 算法时代 算法价格歧视 消费者权益 违法性认定
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算法仁心,工于为公?算法推荐对消费者政治性消费的影响研究 被引量:1
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作者 刘建新 范秀成 李希 《商业经济与管理》 北大核心 2025年第8期5-25,共21页
通过算法向潜在消费者推荐政府倡议或鼓励消费的产品或服务已经成为广为应用的营销策略,但目前的研究主要集中于算法推荐对消费者的信任、采纳或转荐的影响,而它对于消费者政治性消费的影响却严重缺乏关注和研究。基于责任内化理论与自... 通过算法向潜在消费者推荐政府倡议或鼓励消费的产品或服务已经成为广为应用的营销策略,但目前的研究主要集中于算法推荐对消费者的信任、采纳或转荐的影响,而它对于消费者政治性消费的影响却严重缺乏关注和研究。基于责任内化理论与自由意志理论,文章通过构建有调节的双中介模型深入探究了算法推荐影响消费者政治性消费的内在机理与边界条件,并用在线调查和实验研究方法进行了实证检验。一个调查与三个实验研究结果表明:(1)算法推荐确实会影响消费者的政治性消费,并且基于用户相似性算法推荐较之于基于产品相似性算法推荐更有助于增强消费者的政治性消费;(2)责任内化与自主威胁会共同中介算法推荐对消费者政治性消费的影响,其中前者主要起着积极中介效应,而后者主要起着消极中介效应;(3)消费者的权力距离信念会前置调节算法推荐对他们政治性消费的影响,即高权力距离信念者更容易让责任内化中介效应占优,而低权力距离信念者更容易让自主威胁中介效应占优;(4)身份歧视会后置调节双中介效应,即高身份歧视会产生减弱效应,而低身份歧视会产生增强效应。这些研究结论不仅对深化和完善算法推荐理论和政治性消费理论等具有重要的理论意义,而且对厂商、消费者和监管机构等有重要的管理启示。 展开更多
关键词 算法推荐 责任内化 自主威胁 权力距离信念 身份歧视 政治性消费
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城市洪涝条件下车辆失稳风险阈值及判别标准研究进展 被引量:1
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作者 李俊奇 汪辉 +3 位作者 李小静 王宇 郭俊杰 杨程远 《水利水电技术(中英文)》 北大核心 2025年第3期30-45,共16页
【目的】随着城市化进程的加速和极端气候事件的频发,城市洪涝事件日趋严峻,积水路段中的车辆失稳风险也在逐步增加。研究车辆在积水中的失稳风险阈值,对于洪涝风险评估和应急管理具有重要的理论意义和实用价值。【方法】从试验研究、... 【目的】随着城市化进程的加速和极端气候事件的频发,城市洪涝事件日趋严峻,积水路段中的车辆失稳风险也在逐步增加。研究车辆在积水中的失稳风险阈值,对于洪涝风险评估和应急管理具有重要的理论意义和实用价值。【方法】从试验研究、理论分析和数值模拟三个方面系统总结了1967—2024年关于车辆在洪涝积水中失稳阈值的研究成果,评估了依据单一水深/流速、水深流速组合、车辆特征和水动力等因素为现有车辆失稳判别标准的优缺点。【结果】现有水槽试验考虑的影响因素较为有限,足尺试验和非静态车辆的研究较少,有些理论分析缺乏数据的率定验证,部分数值模拟中的水动力模型未进行参数敏感性分析。阈值未充分考虑车辆状况、行驶条件、道路环境等多方面因素。失稳判别标准主要依赖于车辆动力学参数,具有一定的经验性。【结论】未来需对不同类型足尺车辆进行多因素耦合研究,并结合数值模拟,利用机器学习算法分析试验数据,提高洪涝条件下车辆稳定性阈值模型的准确性,制定车辆安全标准。为交通部门和排水系统规划建设部门提供决策依据。 展开更多
关键词 城市洪涝 车辆失稳 风险阈值 判别标准 气候变化 降雨 径流 影响因素
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粮食气味物质的提取、关键组分判别及其在储藏中的应用研究进展
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作者 李慧 洪习文 +1 位作者 王争艳 王艳艳 《食品科学》 EI CAS 北大核心 2025年第1期266-273,共8页
粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成... 粮食气味物质受粮食种类、储藏条件、储藏时间及是否受有害生物污染等多种因素影响,气味物质种类及含量能够及时反映粮食是否变质或受有害生物危害。首先,本文概述目前常用的粮食气味物质的提取和鉴定技术,总结不同状态粮食气味物质组成,发现烷烃类、酸类、醛类和醇类等物质赋予粮食特有的气味,而不同的储藏环境和粮食状态下,其气味物质存在较大差异。其次,探讨粮食中特征气味物质的分析方法,梳理粮食关键气味物质可能的代谢途径,归纳水稻和小麦中特征气味物质,其中稻谷中特征气味物质2-乙酰基-1-吡咯啉的生成机制也已得到初步确认。最后,对气味物质在粮食安全储藏领域的应用进行概述,提出深入分析、挖掘粮食气味物质数据,构建新型预测模型以快速、精准检测粮食品质将成为未来粮食气味物质研究领域的重要方向;同时,部分气味物质也被证实对粮仓中有害生物具有防控作用,将成为未来研发新型绿色储粮药剂的重要来源。 展开更多
关键词 粮食 气味物质 判别方法 代谢途径 安全储藏
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