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Comparison of Efficacy of Various Control Agents for Citrus Psyllid and Advances in Related Research
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作者 Zhihao YE Xiaoshan LI +5 位作者 Haowen ZHANG Yupai ZENG Weifeng HOU Chenglang LIANG Ranran NIE Qianhua JI 《Plant Diseases and Pests》 2025年第2期13-18,23,共7页
Given that the citrus psyllid is the primary vector of citrus Huanglongbing(HLB),there is an urgent need to control this pest to mitigate the spread of the disease.This paper reviews the current research on two predom... Given that the citrus psyllid is the primary vector of citrus Huanglongbing(HLB),there is an urgent need to control this pest to mitigate the spread of the disease.This paper reviews the current research on two predominant control strategies:chemical control and biological control agents,in managing the citrus psyllid.It emphasizes the mechanisms of action,efficacy,and application advancements of these control methods.Finally,the paper analyzes the principal challenges associated with the sustainable management of citrus psyllids and offers perspectives for future research. 展开更多
关键词 CITRUS PSYLLID Chemical CONTROL AGENT Biological CONTROL AGENT EFFICACY comparison
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Multi-Firmware Comparison Based on Evolutionary Algorithm and Trusted Base Point
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作者 Wenbing Wang Yongwen Liu 《Computers, Materials & Continua》 2025年第7期763-790,共28页
Multi-firmware comparison techniques can improve efficiency when auditing firmwares in bulk.How-ever,the problem of matching functions between multiple firmwares has not been studied before.This paper proposes a multi... Multi-firmware comparison techniques can improve efficiency when auditing firmwares in bulk.How-ever,the problem of matching functions between multiple firmwares has not been studied before.This paper proposes a multi-firmware comparison method based on evolutionary algorithms and trusted base points.We first model the multi-firmware comparison as a multi-sequence matching problem.Then,we propose an adaptation function and a population generation method based on trusted base points.Finally,we apply an evolutionary algorithm to find the optimal result.At the same time,we design the similarity of matching results as an evaluation metric to measure the effect of multi-firmware comparison.The experiments show that the proposed method outperforms Bindiff and the string-based method.Precisely,the similarity between the matching results of the proposed method and Bindiff matching results is 61%,and the similarity between the matching results of the proposed method and the string-based method is 62.8%.By sampling and manual verification,the accuracy of the matching results of the proposed method can be about 66.4%. 展开更多
关键词 Multi-firmware comparison evolutionary algorithm multi-sequence matching binary code comparison
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Endoscopic retrograde cholangiopancreatography in pediatric and adult populations:17-year experience from Pakistan with trends,complications,and global comparison
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作者 Noval Zakaria Muhammad U Tahseen +16 位作者 Talha S Niaz Muhammad Asim Asma Yaseen Shanil Kadir Sajida Qureshi Shahriyar Ghazanfar Aftab Leghari Muhammad A Taj Arif R Siddiqui Abeer Altaf Naseer Ahmed Areeba Raza Javeria Salman Umer B Shoaib Mehreen Siyal Abdul K Durvesh Saad K Niaz 《World Journal of Gastrointestinal Endoscopy》 2025年第11期79-89,共11页
BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an essential diagnostic and therapeutic procedure for pancreatobiliary disorders.However,few large-scale studies from South Asia have examined long-ter... BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an essential diagnostic and therapeutic procedure for pancreatobiliary disorders.However,few large-scale studies from South Asia have examined long-term ERCP outcomes,particularly using established quality benchmarks.AIM To evaluate ERCP indications,success rates,complications,and quality performance at a high-volume tertiary care center in Pakistan over a 17-year period.METHODS This retrospective study analyzed 13215 ERCP procedures performed between 2006 and 2023.Data included demographics,indications,cannulation rates,complications,and pediatric cases.Findings were assessed against American Society of Gastroenterology/European Society of Gastrointestinal Endoscopy quality indicators.RESULTS Biliary ERCP accounted for 93.1%of procedures;choledocholithiasis was the most common indication(40%).Cannulation success was 93.9%for biliary and 94.2%for pancreatic ERCP.Pediatric ERCP comprised 4%of cases,mostly for stones and chronic pancreatitis.Bleeding(1.7%)and post-ERCP pancreatitis(2.3%)were the most frequent complications.Performance met or exceeded most American Society of Benchmarks.CONCLUSION This study offers insight into nearly two decades of ERCP practice within a public sector hospital.Our experience echoes the quality and efficiency of ERCP not previously available in Pakistan.As healthcare systems in resourcelimited sectors expand,our findings serve as a reference point.Continued training and quality improvement studies can further enhance ERCP effectiveness in the region and beyond. 展开更多
关键词 Endoscopic retrograde cholangiopancreatography PEDIATRIC Adult populations Global comparison BILIARY PANCREATIC Pakistan
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Implementation of a double trigger condition system based on charge comparison and TOF measurement for the NEDA detector array
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作者 J.M.Deltoro A.Goasduff +19 位作者 F.J.Egea V.González A.Gadea R.M.Pérez-Vidal I.Lazarus M.Kogimtzis L.McNicholl M.Palacz G.Jaworski J.J.Valiente-Dobón J.Nyberg S.Casans A.E.Navarro-Antón E.Sanchis A.Boujrad E.Clément T.Hüyük R.Illicachi O.Stezowski V.Modamio 《Nuclear Science and Techniques》 2025年第2期40-48,共9页
The NEutron Detector Array(NEDA)is designed to be coupled to gamma-ray spectrometers to enhance the sensitivity of the setup by enabling reaction channel selection through counting of the evaporated neutrons.This arti... The NEutron Detector Array(NEDA)is designed to be coupled to gamma-ray spectrometers to enhance the sensitivity of the setup by enabling reaction channel selection through counting of the evaporated neutrons.This article presents the implementation of a double trigger condition system for NEDA,which improves the acquisition of neutrons and reduces the number of gamma rays acquired.Two independent triggers are generated in the double trigger condition system:one based on charge comparison(CC)and the other on time-of-flight(TOF).These triggers can be combined using OR and AND logic,offering four distinct trigger modes.The developed firmware is added to the previous one in the Virtex 6 field programmable gate array(FPGA)present in the system,which also includes signal processing,baseline correction,and various trigger logic blocks.The performance of the trigger system is evaluated using data from the E703 experiment performed at GANIL.The four trigger modes are applied to the same data,and a subsequent offline analysis is performed.It is shown that most of the detected neutrons are preserved with the AND mode,and the total number of gamma rays is significantly reduced.Compared with the CC trigger mode,the OR trigger mode allows increasing the selection of neutrons.In addition,it is demonstrated that if the OR mode is selected,the online CC trigger threshold can be raised without losing neutrons. 展开更多
关键词 Neutron detector Neutron-gamma discrimination Pulse shape analysis TIME-OF-FLIGHT Charge comparison
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Enhanced prediction of occurrence forms of heavy metals in tailings:A systematic comparison of machine learning methods and model integration
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作者 Pengxin Zhao Kechao Li +3 位作者 Nana Zhou Qiusong Chen Min Zhou Chongchong Qi 《International Journal of Minerals,Metallurgy and Materials》 2025年第10期2406-2417,共12页
Tailings produced by mining and ore smelting are a major source of soil pollution.Understanding the speciation of heavy metals(HMs)in tailings is essential for soil remediation and sustainable development.Given the co... Tailings produced by mining and ore smelting are a major source of soil pollution.Understanding the speciation of heavy metals(HMs)in tailings is essential for soil remediation and sustainable development.Given the complex and time-consuming nature of traditional sequential laboratory extraction methods for determining the forms of HMs in tailings,a rapid and precise identification approach is urgently required.To address this issue,a general empirical prediction method for HM occurrence was developed using machine learning(ML).The compositional information of the tailings,properties of the HMs,and sequential extraction steps were used as inputs to calculate the percentages of the seven forms of HMs.After the models were tuned and compared,extreme gradient boosting,gradient boosting decision tree,and categorical boosting methods were found to be the top three performing ML models,with the coefficient of determination(R^(2))values on the testing set exceeding 0.859.Feature importance analysis for these three optimal models indicated that electronegativity was the most important factor affecting the occurrence of HMs,with an average feature importance of 0.4522.The subsequent use of stacking as a model integration method enabled the ability of the ML models to predict HM occurrence forms to be further improved,and resulting in an increase of R^(2) to 0.879.Overall,this study developed a robust technique for predicting the occurrence forms in tailings and provides an important reference for the environmental assessment and recycling of tailings. 展开更多
关键词 TAILINGS sequential extraction occurrence forms model comparison stacking ensemble learning
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Unidirectional quantum private comparison based on quantum private query
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作者 Hexiang Sun Ding Xing +3 位作者 Zhao Dou Jian Li Xiubo Chen Lixiang Li 《Chinese Physics B》 2025年第5期43-53,共11页
Previous bidirectional quantum private comparison(BQPC)protocols cannot meet the requirements in some special application scenarios,where only one party needs to obtain the comparison results without a third party(TP)... Previous bidirectional quantum private comparison(BQPC)protocols cannot meet the requirements in some special application scenarios,where only one party needs to obtain the comparison results without a third party(TP),such as scenarios for authority surveys or healthcare data sharing.In addition to this,the BQPC protocol has the potential of information leakage in multiple comparisons.Therefore,we design a new unidirectional quantum private comparison(UQPC)protocol based on quantum private query(QPQ)protocols with ideal database security and zero failure probability(IDS-ZF),for the reason that they have excellent unidirectionality and security.Concretely,we design a UQPC protocol based on Wei et al.’s work[IEEE Transactions on Computers 672(2017)]and it includes an authentication process to increase the resistance to outside attacks.Moreover,we generalize the protocol and propose a general model that can transform a QPQ protocol with or without the IDS-ZF property into a secure UQPC protocol.Finally,our study shows that protocols using our model are secure,practical,and have the IDS-ZF property. 展开更多
关键词 quantum private comparison UNIDIRECTIONALITY IDENTIFICATION general model
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Understanding Young Adults’Social Media Anxiety:Mediating Role of Upward Social Comparison and the Moderating Role of Psychological Resilience
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作者 Jinqian Li Jianhong Wu 《International Journal of Mental Health Promotion》 2025年第12期1883-1896,共14页
Background:Platform algorithms driving content presentation are profoundly shaping the experience of younger users.While prior research has examined anxiety stemming from young adults’social media usage,the link betw... Background:Platform algorithms driving content presentation are profoundly shaping the experience of younger users.While prior research has examined anxiety stemming from young adults’social media usage,the link between upward social comparison and anxiety remains unclear.This study aims to investigate the mediating role of upward social comparison in this relationship and determine the moderating role of psychological resilience.Methods:A cross-sectional survey was conducted among 562 young Chinese adults aged 18–35(53%female).Data were collected via an online questionnaire employing validated measurement instruments,including scales for social media usage patterns,upward comparator behaviour(INCOM),anxiety levels(GAD-7),and psychological resilience(RSA).Correlation analysis,mediation analysis,and moderation analysis were conducted using SPSS 29.0.Results:As predicted,the results indicate that upward social comparison mediates the relationship between both active(β=−0.11,95%CI=[−0.15,−0.08])and passive(β=0.11,95%CI=[0.07,0.15])social media use and anxiety.Furthermore,psychological resilience(β_(low)=0.10,95%CI=[0.06,0.14];β_(high)=0.05,95%CI=[0.01,0.09])moderated the indirect effect of passive social media use on anxiety through upward social comparison.Conclusion:The findings indicate that upward social comparison significantly influences the anxiety experienced by young social media users,with psychological resilience playing a crucial moderating role.These results offer valuable insights for optimizing content recommendation algorithms on social media platforms to better support young adults’mental health. 展开更多
关键词 Psychological well-being digital mental health upward social comparison algorithmic stress psychological resilience collectivist coping young adults
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Machine learning model comparison and ensemble for predicting different morphological fractions of heavy metal elements in tailings and mine waste
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作者 FENG Yu-xin HU Tao +4 位作者 ZHOU Na-na ZHOU Min BARKHORDARI Mohammad Sadegh LI Ke-chao QI Chong-chong 《Journal of Central South University》 2025年第9期3557-3573,共17页
Driven by rapid technological advancements and economic growth,mineral extraction and metal refining have increased dramatically,generating huge volumes of tailings and mine waste(TMWs).Investigating the morphological... Driven by rapid technological advancements and economic growth,mineral extraction and metal refining have increased dramatically,generating huge volumes of tailings and mine waste(TMWs).Investigating the morphological fractions of heavy metals and metalloids(HMMs)in TMWs is key to evaluating their leaching potential into the environment;however,traditional experiments are time-consuming and labor-intensive.In this study,10 machine learning(ML)algorithms were used and compared for rapidly predicting the morphological fractions of HMMs in TMWs.A dataset comprising 2376 data points was used,with mineral composition,elemental properties,and total concentration used as inputs and concentration of morphological fraction used as output.After grid search optimization,the extra tree model performed the best,achieving coefficient of determination(R2)of 0.946 and 0.942 on the validation and test sets,respectively.Electronegativity was found to have the greatest impact on the morphological fraction.The models’performance was enhanced by applying an ensemble method to the top three optimal ML models,including gradient boosting decision tree,extra trees and categorical boosting.Overall,the proposed framework can accurately predict the concentrations of different morphological fractions of HMMs in TMWs.This approach can minimize detection time,aid in the safe management and recovery of TMWs. 展开更多
关键词 tailings and mine waste morphological fractions model comparison machine learning model ensemble
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Systematic calibration of a 2-m Ring Solar Telescope based on local interferometry and model comparison
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作者 Renai Liu Jinpeng Li +2 位作者 Zuozifei Song Changyu Zeng Yichun Dai 《Astronomical Techniques and Instruments》 2025年第3期175-185,共11页
To address the installation challenges of a 2-m ring Gregorian telescope system,and similar optical systems with a small width-to-radius ratio,we propose a detection method combining local interferometry with a compar... To address the installation challenges of a 2-m ring Gregorian telescope system,and similar optical systems with a small width-to-radius ratio,we propose a detection method combining local interferometry with a comparison model.This method enhances the precision of system calibration by establishing a dataset that delineates the relationship between secondary mirror misalignment and wavefront aberration,subsequently inferring the misalignment from interferometric detection results during the calibration process.For the 2-m ring telescope,we develop a detection model using five local sub-apertures,enabling a root-mean-square detection accuracy of 0:0225λ(λ=632:8 nm)for full-aperture wavefront aberration.The calibration results for the 2-m Ring Solar Telescope system indicate that the root-mean-square value of sub-aperture wavefront aberration reaches 0.104λ,and the root-mean-square value of spliced full-aperture measurement yields reaches 0.112λ.This method offers a novel approach for calibrating small width-toradius ratio telescope systems and can be applied to the calibration of other irregular-aperture optical systems. 展开更多
关键词 Local aperture Model comparison 2-m Ring Solar Telescope System calibration Splicing algorithm
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西太平洋海域船载CTD仪与现场盐度计观测资料的比对分析
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作者 王延清 陈磊 +3 位作者 栾振东 张林林 孙毅 潘俊 《海洋科学进展》 北大核心 2026年第1期62-70,共9页
盐度是海洋水文调查的主要观测变量之一,比对分析航次的盐度数据是航次数据质控的重要步骤。本文通过与实验室盐度计比对分析的方式,对2023年11月开展的为期2个月的西太平洋开放航次的CTD(Conductivity, Temperature, and Depth)盐度数... 盐度是海洋水文调查的主要观测变量之一,比对分析航次的盐度数据是航次数据质控的重要步骤。本文通过与实验室盐度计比对分析的方式,对2023年11月开展的为期2个月的西太平洋开放航次的CTD(Conductivity, Temperature, and Depth)盐度数据进行比对,数据分析表明,本航次CTD电导率传感器(用于盐度测量)处于稳定状态。在调查时间内,该海域600 m以深水层及5 m、25 m水层的CTD盐度数据和实验室盐度计结果具有较好的一致性,符合盐度比对取样要求。根据剖面盐度随深度的变化结果,也确认了600 m以深水层及5 m、25 m水层都处于较低盐度变化状态,说明该水层是盐度“比较均匀的水层”。基于该结果,建议冬季在该海域进行CTD盐度资料比对分析时,可以选择600 m以深水层。同时,在其他季节也需要对研究区5 m、25 m的水层进行比对分析,以进一步研究该水层作为比对水层的可行性。 展开更多
关键词 盐度 实验室盐度计 CTD 比对分析 西太平洋
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人工智能赋能个性化教学的实践路径与策略研究——基于美国、英国、芬兰三国的政策与行动分析
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作者 刘智 余曼丽 +1 位作者 龙陶陶 孙建文 《中国电化教育》 北大核心 2026年第2期112-122,共11页
在教育数字化转型持续推进的背景下,人工智能正深度重构个性化教学的实现机制。该研究以美国、英国和芬兰三国的主要政策和实践为主要分析对象,围绕基本思路、实践行动和典型项目进行文献分析。跨案例综合分析表明,三国的主要推进路径... 在教育数字化转型持续推进的背景下,人工智能正深度重构个性化教学的实现机制。该研究以美国、英国和芬兰三国的主要政策和实践为主要分析对象,围绕基本思路、实践行动和典型项目进行文献分析。跨案例综合分析表明,三国的主要推进路径表现为教育政策引领、学习路径重构、教育资源适配、教师专业赋能、学生素养培育与公平普惠保障等六方面。基于上述研究发现,考量我国国情与发展现状,提出优化顶层设计与多部门协同、深化行为档案驱动机制、完善智能资源生成与适配体系、系统强化师生数字能力与AI素养、构建协同治理的数字公平生态等五项针对性的实施策略,以期为我国AI赋能大规模因材施教的本土化路径探索提供比较视野与实践启示。 展开更多
关键词 人工智能 个性化教学 国际比较 教育政策
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国内外量水堰槽技术标准现状对比分析
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作者 刘彧 宋小艳 +3 位作者 吴丹 齐黎黎 徐红 刘姗姗 《人民黄河》 北大核心 2026年第2期35-40,141,共7页
水量计量作为水资源管理与利用的关键环节,其技术标准对于确保测量准确性、水资源合理配置具有重要意义。通过对比分析国内外量水堰槽(特设量水设施)的技术标准,重点探讨了薄壁堰、宽顶堰、剖面堰及长短喉道量水槽等关键设备设施的产品... 水量计量作为水资源管理与利用的关键环节,其技术标准对于确保测量准确性、水资源合理配置具有重要意义。通过对比分析国内外量水堰槽(特设量水设施)的技术标准,重点探讨了薄壁堰、宽顶堰、剖面堰及长短喉道量水槽等关键设备设施的产品技术参数、计量性能及测量方法技术参数。研究发现,国内外在量水堰槽的分类、结构尺寸、测量方法及应用限制条件等方面存在显著差异。通过开展国内外水量计量技术标准主要技术参数对比分析,可为我国水量计量技术标准的制定和优化提供技术参考,提升标准的质量和可操作性,从而更好地服务于水利行业的水量计量实践,贯彻落实最严格的水资源管理制度,并为实施国家计量发展规划及水利中心工作提供有力支撑。 展开更多
关键词 量水堰槽 技术标准 参数比对 分析
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改进熵权和灰关联模型的装备能力评估
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作者 王博 周文雅 +2 位作者 柯肇捷 宗飞 刘君 《系统工程与电子技术》 北大核心 2026年第2期524-534,共11页
针对传统信息熵法和灰关联模型对装备试验数据量和质量的要求过高、难以保证装备性能准确评估的问题,提出一种改进的熵权法和灰关联模型。该方法采用Bayes Bootstrap方法对小样本试验数据进行参数估计,计算出装备指标参数的点估计值,并... 针对传统信息熵法和灰关联模型对装备试验数据量和质量的要求过高、难以保证装备性能准确评估的问题,提出一种改进的熵权法和灰关联模型。该方法采用Bayes Bootstrap方法对小样本试验数据进行参数估计,计算出装备指标参数的点估计值,并构造判断比较矩阵;利用信息熵法结合装备评估指标的参数估计值完成指标客观权重的确定;通过考察装备指标参数点估计值与正、负理想解的位置关系,求解每个装备指标点估计值的正、负关联系数并聚合得出评估结果。运用该方法对侦察卫星系统探测能力进行评估,并与传统信息熵法和灰关联模型进行对比,证明了改进熵权和灰关联模型的科学性和有效性,为其在评估方法中的运用提供参考。 展开更多
关键词 信息熵 参数估计 判断比较矩阵 理想解 灰关联
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城市轨道交通引起的室内噪声规范对比分析研究
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作者 唐汐 杨若腾 +3 位作者 陈嘉梁 孙晓静 黄齐武 崔日新 《铁道标准设计》 北大核心 2026年第3期206-211,共6页
随着城市轨道交通的快速发展,交通线路不可避免地穿越商业区域及居民住宅区域,列车运行引起的沿线建筑物室内噪声问题愈发严重。在进行建筑物室内噪声测量和评价时,采用不同的标准规范往往造成结论不同,因此有必要明确常用规范的异同。... 随着城市轨道交通的快速发展,交通线路不可避免地穿越商业区域及居民住宅区域,列车运行引起的沿线建筑物室内噪声问题愈发严重。在进行建筑物室内噪声测量和评价时,采用不同的标准规范往往造成结论不同,因此有必要明确常用规范的异同。通过开展轨道交通高架线沿线3处建筑物噪声测试,对比分析国内几种常用室内噪声标准规范中限值的差异。结果表明:(1)在列车运行同时段下,密集20 min等效声级大于同时段的1 h等效声级,1 h等效声级与列车运行密度存在正相关关系;(2)GB 55016—2021《建筑环境通用规范》的限值要比GB 50118—2010《民用建筑隔声设计规范》严格;(3)同一测试结果采用不同标准进行评价时会导致结论不同,因此在进行声环境评估时要根据振源、测试环境等多因素选择适合的标准规范。 展开更多
关键词 轨道交通 环境噪声 A计权声压级 规范对比 评价指标
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多k位数阈值的谓词加密方案
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作者 李婷 陈振华 《计算机应用与软件》 北大核心 2026年第1期338-347,共10页
现有支持比较大小的谓词加密方案没有考虑属性值的排序位置,且大多数方案没有实现更强的隐私性——属性隐藏。针对这两个问题,提出一种具有属性隐藏的多k位数阈值谓词加密方案。设计一种新的编码,将多个排序后的属性值和多个阈值的比较... 现有支持比较大小的谓词加密方案没有考虑属性值的排序位置,且大多数方案没有实现更强的隐私性——属性隐藏。针对这两个问题,提出一种具有属性隐藏的多k位数阈值谓词加密方案。设计一种新的编码,将多个排序后的属性值和多个阈值的比较大小转化为多内积问题;采用对偶向量空间上的内积加密技术,构造随机数等式实现多内积问题;构造属性盲化方法实现属性隐藏。安全性证明和性能分析表明,所提方案在标准模型下是可以抵抗选择明文攻击的,且具备较好的存储性能。 展开更多
关键词 谓词加密 k 位数阈值 比较大小 属性隐藏
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硫包衣缓释肥提升水稻产量及氮肥利用率的技术途径
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作者 董桂春 王子涵 +10 位作者 王树深 李杰 霍晓晴 杨瑞 周娟 舒小伟 李妍 曹靓婧 王子瑞 姚友礼 黄建晔 《中国农业科学》 北大核心 2026年第1期57-77,共21页
【目的】探究硫包衣缓释肥中缓释氮4个不同释放周期的产品的施用方法,厘清缓释氮产品是单一施用还是组合施用、是否要与速效氮配施、如何优化配施的问题,旨在实现水稻产量和氮肥利用率的协同提高。【方法】于2022—2024年在江苏扬州和常... 【目的】探究硫包衣缓释肥中缓释氮4个不同释放周期的产品的施用方法,厘清缓释氮产品是单一施用还是组合施用、是否要与速效氮配施、如何优化配施的问题,旨在实现水稻产量和氮肥利用率的协同提高。【方法】于2022—2024年在江苏扬州和常州,以南粳9108与南粳46为供试材料,设计缓释氮产品比较、产品组合筛选、肥料品种比较、缓速掺混配比、速效肥不同施用时期、缓释氮组合配方优选等试验,研究硫包衣缓释肥施用方法对水稻产量形成和氮素吸收利用的影响。【结果】(1)秸秆还田处理的水稻产量较半量还田、不还田处理分别显著提高4.50%、8.88%,氮肥利用率较其他两处理分别提高11.35%、25.64%。(2)缓释氮60 d产品的产量比30、90、120 d产品分别高4.10%、15.68%、19.09%,但低于常规精确定量4.13%;60 d产品氮肥利用率总体而言大于其他缓释氮产品,平均高8.68%;秸秆不还田、半量还田处理略高于常规精确定量处理9.88%、0.93%,全量还田处理低于常规精确定量处理4.57%。(3)缓释氮产品以“3+6+9”组合的产量、氮肥利用率最高,但均低于常规精确定量。(4)缓速掺混配比7﹕3处理的水稻产量、氮素积累量、氮肥利用率均最高,比常规精确定量处理平均分别高4.31%、3.25%、6.15%;在此处理下,速效肥作分蘖肥(生育期中等的品种)或作促花肥(生育期较长的品种),产量、氮素积累量、氮肥利用率均协同提高。产量提高主要是由于在水稻穗数足够的基础上每穗粒数显著增加。(5)缓释氮产品按30 d﹕60 d﹕90 d=1﹕4﹕1掺混时,水稻的产量、氮素积累量、氮肥利用率均为最高,较常规精确定量处理分别增加3.76%、5.66%、13.35%,这与其叶面积系数、库容量、生物产量均显著提高有密切的关系。【结论】缓释氮按30 d﹕60 d﹕90 d=1﹕4﹕1比例混合,缓释氮与速效氮以7﹕3配施,缓释肥一次性基施,速效肥作分蘖肥(生育期150 d左右的品种)或促花肥(生育期160 d以上的品种)一次性施用,产量、氮肥利用率较常规精确定量处理分别增加3.76%、13.35%,是硫包衣缓释肥实现水稻产量和氮肥利用率协同提高比较优化的施用方法。 展开更多
关键词 水稻 缓释氮产品比较与组合筛选 缓释肥优化施用 产量 氮素吸收利用
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显著车轮虫宿主新记录及种群比较研究
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作者 唐发辉 余雪雪 赵元莙 《水生生物学报》 北大核心 2026年第3期154-163,共10页
为探索显著车轮虫(Trichodina nobillis Chen,1963)种内分化及其近缘种间的关系,本研究采集获得来自重庆永川与四川眉山地区养殖丁鱥(Tinca tinca)鳃部的显著车轮虫(CQ种群与SC种群),在新获得的两种群形态数据及SSU rDNA序列基础上,比... 为探索显著车轮虫(Trichodina nobillis Chen,1963)种内分化及其近缘种间的关系,本研究采集获得来自重庆永川与四川眉山地区养殖丁鱥(Tinca tinca)鳃部的显著车轮虫(CQ种群与SC种群),在新获得的两种群形态数据及SSU rDNA序列基础上,比较研究了显著车轮虫的种群差异并厘定了与近缘种的种间关系。基于形态学研究结果:显著车轮虫两种群附着盘的齿体形态高度一致,但SC种群齿体整体较CQ种群发达,且CQ种群缺明显的后突起;附着盘量化统计研究表明两种群在齿体纵长、齿棘长、辐线数与齿环比例方面均存在显著差异(P<0.05),另PCA分析结果亦支持了二者种内差异的存在。基于SSU rDNA的分子系统分析结果:同宿主来源的显著车轮虫种群间的序列相似度低于且遗传距离大于不同宿主来源的种群,即同宿主来源的遗传差异大于不同宿主的遗传差异,由此推断,宿主的差异并非影响显著车轮虫种群分化的首要因素。基于寄生特性的分析结果,显著车轮虫对宿主及寄生部位均无特异性选择,属于一类生态位较为宽泛的非专性寄生虫。本研究报道的丁鱥为显著车轮虫的宿主新记录。基于分子证据,本研究还进一步对显著车轮虫的近缘种,即登录号为AY788099的异齿车轮虫进行了种类厘定,以期为后续探讨显著车轮虫与近缘种之间的关系研究奠定基础,同时为水产养殖的车轮虫病害防控提供理论资料。 展开更多
关键词 形态数据 SSU rDNA 丁鱥 近缘种 种群比较 显著车轮虫
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沪渝蓉高铁钟祥汉江特大桥主桥桥型方案研究
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作者 王存国 唐代伟 +1 位作者 王明亮 王新国 《铁道标准设计》 北大核心 2026年第3期86-92,99,共8页
沪渝蓉高铁钟祥汉江特大桥是沪渝蓉高铁武汉至宜昌段的控制性工程,根据通航及防洪等限制条件,并结合该桥需满足时速350 km无砟轨道技术标准,提出(60+78+270+78+60)m预应力混凝土梁斜拉桥及(142+270+142)m部分斜拉桥两种桥型方案,从结构... 沪渝蓉高铁钟祥汉江特大桥是沪渝蓉高铁武汉至宜昌段的控制性工程,根据通航及防洪等限制条件,并结合该桥需满足时速350 km无砟轨道技术标准,提出(60+78+270+78+60)m预应力混凝土梁斜拉桥及(142+270+142)m部分斜拉桥两种桥型方案,从结构受力、工程规模、施工难度及经济性等方面对上述桥型方案比选分析,并深入分析主梁工后徐变的影响因素。主要结论及创新点如下:(1)两种桥型方案均能满足设计要求,但预应力混凝土梁斜拉桥方案降低线路高程14 m,减小工程整体规模,节省投资约2500万,且工期及景观效果均优于部分斜拉桥方案,综合优势明显,推荐预应力混凝土梁斜拉桥方案作为本工程实施方案;(2)预应力混凝土梁斜拉桥主梁工后徐变受成桥状态、索塔刚度、索塔高度、主梁截面材质及无砟轨道铺设前静置期等因素影响较大,桥梁结构设计中统筹考虑工后徐变变形影响因素,主梁工后徐变变形值控制在25 mm以内。大跨度混凝土桥梁桥型设计及徐变变形控制技术相关成果可为类似工程提供参考借鉴。 展开更多
关键词 高速铁路 桥型方案 混凝土梁斜拉桥 部分斜拉桥 综合比选 徐变变形
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我国一对二督导实施现状调查
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作者 陈瑜 裴涛 桑志芹 《中国临床心理学杂志》 北大核心 2026年第1期236-241,共6页
目的:了解我国心理咨询行业中一对二督导的实施现状。方法:采用半结构式访谈对3所已规模化实施一对二督导的机构负责人进行访谈,采用自编问卷对156位受督者和82位督导师进行问卷调查。结果:(1)一对二督导在我国因督导师资源不足而兴起;... 目的:了解我国心理咨询行业中一对二督导的实施现状。方法:采用半结构式访谈对3所已规模化实施一对二督导的机构负责人进行访谈,采用自编问卷对156位受督者和82位督导师进行问卷调查。结果:(1)一对二督导在我国因督导师资源不足而兴起;(2)一对二督导的设置与实施方式多样,现实设置与理想意愿差异显著(P<0.05);(3)62.9%的受督者不报个案时参与度较高;(4)78.2%的受督者及85.0%的督导师认为一对二督导与个体督导相比效果相当或更优,85.9%的受督者及82.8%的督导师认为一对二督导比团体督导更有效;(5)一对二督导中,受督者的体验感优于团体督导,督导师的挑战感大于个体督导。结论:我国一对二督导的实施方式多样且有待完善,一对二督导具有一定的有效性。 展开更多
关键词 一对二督导 实施背景 实施方式 效果比较 体验比较
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贵州省辣椒品种成熟期果实品质评价
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作者 韩畅 蒋琪 +3 位作者 张相春 吕朝燕 隋常玲 陈志峰 《农业工程》 2026年第1期123-129,共7页
对贵州省合肥市2种不同血缘辣椒品种(遵椒4号和卓椒新52号)成熟期果实品质指标进行测试,结果表明,2个辣椒品种品质指标均呈现出不同程度的差异性。果实形状方面,遵椒4号在果长、果宽、单果质量和果肉厚度等指标上优于卓椒新52号;辣椒基... 对贵州省合肥市2种不同血缘辣椒品种(遵椒4号和卓椒新52号)成熟期果实品质指标进行测试,结果表明,2个辣椒品种品质指标均呈现出不同程度的差异性。果实形状方面,遵椒4号在果长、果宽、单果质量和果肉厚度等指标上优于卓椒新52号;辣椒基本成分方面,遵椒4号在水分质量分数指标上优于卓椒新52号,而卓椒新52号在总灰分含量、粗蛋白含量、粗纤维含量、维生素C含量及辣椒素含量等指标均优于遵椒4号;果实色差方面,卓椒新52号果实亮度及鲜红程度上优于遵椒4号;果实质地方面,遵椒4号在果实弹性和咀嚼性方面优于卓椒新52号,而卓椒新52号在硬度方面优于遵椒4号;果实感官检验方面,11个感官检验指标中,遵椒4号在果肉色及香气方面优于卓椒新52号,而卓椒新52号在多个辣味指标方面均优于遵椒4号。 展开更多
关键词 辣椒 品质 质地特性 感官分析 品种对比
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