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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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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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国外创业投资税收优惠政策比较研究
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作者 朱为群 陶瑞翠 《经济与管理评论》 北大核心 2026年第1期66-81,共16页
基于政策受益主体、实施客体、实施机制和实施力度等要素,系统分析了20个国家39项现行创业投资税收优惠政策。研究发现:政策受益主体基于投资目的、规模、方式及持有期限界定合格创投行为而定;政策实施客体为未上市、初创阶段、合规经... 基于政策受益主体、实施客体、实施机制和实施力度等要素,系统分析了20个国家39项现行创业投资税收优惠政策。研究发现:政策受益主体基于投资目的、规模、方式及持有期限界定合格创投行为而定;政策实施客体为未上市、初创阶段、合规经营且财务健康的中小企业;政策实施机制主要采用投资阶段的所得税税额式优惠;不同实施方式的优惠力度差异较大,税额式优惠最为常见。基于国际比较和我国实践,提出如下建议:明确受益主体,引入“穿透”条款和投资目的;完善实施客体,引入财务健康要求;优化激励机制,推动税基式优惠转向税额式优惠;加大优惠力度,提高抵免比例并完善亏损跨期结转机制。 展开更多
关键词 创业投资 税收优惠 所得税 国际比较
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旅游业数字化创新发展特征及趋势研究——基于专利和案例比较
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作者 郭峦 谢子君 《四川旅游学院学报》 2026年第1期25-37,共13页
文章通过整合2018—2024年12 885项旅游业数字专利申请数据及文化和旅游部872个数字化创新案例,采用时间趋势分析、热点词频分析、空间分布分析和交叉对比分析等方法,归纳我国旅游业数字化创新的发展特征、未来趋势及管理启示。研究发现... 文章通过整合2018—2024年12 885项旅游业数字专利申请数据及文化和旅游部872个数字化创新案例,采用时间趋势分析、热点词频分析、空间分布分析和交叉对比分析等方法,归纳我国旅游业数字化创新的发展特征、未来趋势及管理启示。研究发现:(1)旅游业数字化创新受多重因素共同驱动,整体呈良好发展态势,但专利技术孵化与案例市场响应存在异步性;(2)专利聚焦技术供给,案例侧重市场响应,二者存在结构性差异;(3)区域创新呈“东强西弱”梯度分布态势,跨区域合作不足,未来旅游业数字创新将进一步向“研发—应用”“技术—体验”“区域协同”推进。据此,文章提出优化不同创新主体与区域间的科研协作体系,健全旅游领域专利技术的协同互补机制,革新旅游专业人才的培育路径,加强技术革新与旅游数智化的深度融合等建议,以期为旅游业数字化高质量均衡发展提供理论依据与发展启示。 展开更多
关键词 旅游业 数字化创新 专利分析 案例比较 区域差异
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基于纵联比较原理的广域配电网继电保护方法
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作者 刘震宇 《自动化技术与应用》 2026年第1期37-40,共4页
保护装置的动作选择性能易受到保护范围和保护延时的影响,导致保护装置易出现误动、拒动和抢动的问题,使得装置无法及时发现系统故障,保护的实效性较差。为此,提出基于纵联比较原理的广域配电网继电保护方法研究。依据纵联比较原理,设... 保护装置的动作选择性能易受到保护范围和保护延时的影响,导致保护装置易出现误动、拒动和抢动的问题,使得装置无法及时发现系统故障,保护的实效性较差。为此,提出基于纵联比较原理的广域配电网继电保护方法研究。依据纵联比较原理,设计电力系统故障识别判据,根据首端故障线模电流与末端故障线模电流之间的关系,确定系统故障类型,并求取保护装置的动作起始值与整定值,通过设置保护区域系数维护保护装置的选择性能,避免误动、拒动和抢动现象,并结合保护范围与保护延时计算纵联保护距离,基于此,依据系统故障位置生成继电保护方案。实验结果表明,所提方法输出的保护动作时间较小,保护实效性较好。 展开更多
关键词 纵联比较原理 广域配电网 整定值 系统故障 继电保护
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高活性贝利特硅酸盐水泥熟料与普通硅酸盐水泥熟料主要性能对比
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作者 刘艳军 孙越男 +1 位作者 宋子新 马军民 《水泥》 2026年第1期1-4,共4页
在历时15年的实验室研究、工业化生产和工程应用基础上,本文参考GB/T 21372—2024《硅酸盐水泥熟料》标准对比了高活性贝利特硅酸盐水泥熟料和普通硅酸盐水泥熟料的主要性能指标,包括主要熟料矿物组成、化学成分、凝结时间、强度、水化... 在历时15年的实验室研究、工业化生产和工程应用基础上,本文参考GB/T 21372—2024《硅酸盐水泥熟料》标准对比了高活性贝利特硅酸盐水泥熟料和普通硅酸盐水泥熟料的主要性能指标,包括主要熟料矿物组成、化学成分、凝结时间、强度、水化热等。对比结果表明,高活性贝利特硅酸盐水泥熟料具有等同或优于普通硅酸盐水泥熟料的物理、力学和耐久性能,完全可以规模化替代普通硅酸盐水泥熟料生产通用硅酸盐水泥产品,对促进我国水泥行业高质量绿色低碳发展具有重要意义。 展开更多
关键词 高活性贝利特熟料 硅酸盐水泥熟料 性能对比
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Comparison of stand structure and growth between artificial and natural forests of Pinus sylvestiris var. mongolica on sandy land 被引量:27
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作者 朱教君 范志平 +2 位作者 曾德慧 姜凤岐 MATSUZAKI Takeshi 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期103-111,共9页
Mongolian pine (Pinus sylvestiris Linnaeus var. mongolica Litvinov) as a valuable conifer tree species has been broadly introduced to the sandy land areas in 揟hree North?regions (North, northwest and northeast of Chi... Mongolian pine (Pinus sylvestiris Linnaeus var. mongolica Litvinov) as a valuable conifer tree species has been broadly introduced to the sandy land areas in 揟hree North?regions (North, northwest and northeast of China), but many problems occurred in the earliest Mongolian pine plantations in Zhanggutai, Zhangwu County, Liaoning Province (ZZL). In order to clarify the reason, comprehensive investigations were carried out on differences in structure characteristics, growth processes and ecological factors between artificial stands (the first plantation established in ZZL in 1950s) and natural stands (the origin forests of the tree species in Honghuaerji, Inner Mongolia) on sandy land. The results showed that variation of diameter-class distributions in artificial stands and natural stands could be described by Weibull and Normal distribution models, respectively. Chapman-Richards growth model was employed to reconstruct the growth process of Mongolian pine based on the data from field investigation and stem analysis. The ages of maximum of relative growth rate and average growth rate of DBH, height, and volume of planted trees were 11, 22 years, 8, 15 years and 35, 59 years earlier than those of natural stand trees, respectively. In respect of the incremental acceleration of volume, the artificial and natural stands reached their maximum values at 14 years and 33 years respectively. The quantitative maturity ages of artificial stands and natural stands were 43 years and 102 years respectively. It was concluded that the life span of the Mongolian pine trees in natural stands was about 60 years longer than those in artificial stands. The differences mentioned above between artificial and natural Mongolian pine forests on sandy land were partially attributed to the drastic variations of ecological conditions such as latitude, temperature, precipitation, evaporation and height above sea level. Human beings' disturbances and higher density in plantation forest may be ascribed as additional reasons. Those results may be potentially useful for the management and afforestation of Mongolian pine plantations on sandy land in arid and semi-arid areas. 展开更多
关键词 Pinus sylvestiris var. mongolica Mongolian pine Sandy land comparison Growth model
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Comparison of the City Water Consumption Short-Term Forecasting Methods 被引量:7
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作者 刘洪波 张宏伟 《Transactions of Tianjin University》 EI CAS 2002年第3期211-215,共5页
There are a lot of methods in city water consumption short-term forecasting both inside and outside the country. But among these methods there exist many advantages and shortcomings in model establishing, solving and ... There are a lot of methods in city water consumption short-term forecasting both inside and outside the country. But among these methods there exist many advantages and shortcomings in model establishing, solving and predicting accuracy, speed, applicability. This article draws lessons from other realm mature methods after many years′ study. It′s systematically studied and compared to predict the water consumption in accuracy, speed, effect and applicability among the time series triangle function method, artificial neural network method, gray system theories method, wavelet analytical method. 展开更多
关键词 city water consumption short-term forecasting method comparison APPLICABILITY
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Distribution Characteristics of Geohazards Induced by the Lushan Earthquake and Their Comparisons with the Wenchuan Earthquake 被引量:8
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作者 Zhiqiang Yin Wuji Zhao Xiaoguang Qin 《Journal of Earth Science》 SCIE CAS CSCD 2014年第5期912-923,共12页
The Lushan Earthquake induced a large number of geohazards. They are widely distributed and caused serious damages. The basic characteristics, formation mechanisms and typical cases of geohazards induced by Lushan Ear... The Lushan Earthquake induced a large number of geohazards. They are widely distributed and caused serious damages. The basic characteristics, formation mechanisms and typical cases of geohazards induced by Lushan Earthquake are described, and compares to the relationships of Lushan and Wenchuan earthquakes between geohazards and earthquake magnitude, geomorphology, slope angle, elevation and seismic intensity in the most affected areas in the article.(1) The numbers and volumes of landslides and rockslides differ significantly between the two earthquakes due to their differing magnitudes. The Lushan Earthquake is associated with fewer and smaller-magnitude geohazards, within the immediate area, which mainly consist of small-and medium-sized shallow landslides and rockslides, and occur on steep slopes and mountain valleys. The largest landslide induced by Lushan Earthquake is the Gangoutou Landslide debris flow with a residual volume of about 2.48×106 m3. The most dangerous debris flow is at Lengmugou gulley in Baoxing County, which has similar geomorphological features and disaster modes as a previous disaster in Zhouqu County, Gansu Province.(2) Geohazards induced by the Lushan Earthquake show four mechanisms: cracking-rockslides-collision- scraping and then debris flows, cracking-rockslides, vibration-rainfall-rockslides-landslide and then debris flow, vibration-throwing or scrolling.(3) There are significant similarities and differences between the geohazards induced by these two earthquakes. The types of geohazards are the same but the volume, quantity and other factors differ: geohazards are concentrated on slope angles of 10°-40° in the Lushan Earthquake area, especially within 10°-20°, and at absolute elevation of 500-2000 m above sea level(a.s.l.). Geohazards within the Wenchuan Earthquake area are concentrated on steeper slope angles of 30°-40° at higher absolute elevations of 1500-2000 m.s.l.. 展开更多
关键词 Lushan Earthquake Wenchuan Earthquake GEOHAZARDS basic characteristics comparison.
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NEW PRINCIPLE FOR DIRECTIONAL COMPARISON CARRIER PROTECTION OF EHV TRANSMISSION LINES 被引量:1
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作者 王钢 李遥 +2 位作者 余晓丹 刘众仆 贺家李 《Transactions of Tianjin University》 EI CAS 1998年第2期6-10,共5页
The increasing scale and complexity of power systems require high performance and high reliability of power system protection.Protective relaying based on directional comparison with power line carrier or microwave ch... The increasing scale and complexity of power systems require high performance and high reliability of power system protection.Protective relaying based on directional comparison with power line carrier or microwave channels is the most suitable protection scheme for long distance EHV transmission lines and is widely used in power systems.The key element of such protection is a directional relay used to discriminate the fault direction.In order to overcome the disadvantages of conventional directional relays,the authors of this paper put forward the directional comparison carrier protection based on the artificial neural network(ANN).The protection is extensively tested using electromagnetic transient program (EMTP) under various electric power system operating and fault conditions.It is proved that the directional comparison carrier protection based on ANN,which can recognize various fault patterns of the protected transmission line(such as fault direction,fault phases etc.)correctly in any kind of operating and fault conditions and the whole process,is satisfactory for EHV transmission line protection. 展开更多
关键词 artificial neural network EHV transmission line directional comparison carrier protection
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Comparison on Winter Wheat Yield Estimating Models Based on Radarsat-2 and HJ Satellite in Huaihe River Region 被引量:1
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作者 范伟 陈磊 +2 位作者 陈娟 闫洪凯 刘韬 《Agricultural Science & Technology》 CAS 2016年第4期1019-1023,共5页
The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model... The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model. With Shou County and Huaiyuan County of Anhui Province as the experimental fields of winter wheat producing areas, the linear winter wheat yield estimating models were established by adopting backscattering coefficient and Normalized Difference Vegetation Index(NDVI) based on images from the synthetic aperture radar(SAR)—RDARSAT-2 and HJ satellite photographed in mid-April and early May, 2014, and then comparisons were conducted on the accuracy of the yield estimating models. The accuracies of the yield estimating models established using co-polarized(HH) and cross-polarized(HV) modes of SAR in Jiangou Town, Shou County were 68.37% and 74.01%, respectively, while the accuracies in Longkang Town, Huaiyuan County were 63.10%and 69.10%, respectively. Accuracies of yield estimating models established by HJ satellite data were 69.52% and 66.43% in Shou County and Huaiyuan County, respectively. Accuracies of winter yield estimating model based on HJ satellite data and that based on SAR were closed, and the yield difference of winter wheat in the lodging region was analyzed in detail. The model results laid the foundation and accumulated experience for the verification, parameters correction and promotion of the winter wheat yield estimating model. 展开更多
关键词 Winter wheat yield estimating model Synthetic aperture radar RADARSAT-2 HJ satellite Model comparison
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Cross-cultural Comparison of Cognitive Structure and Behavior of Waterfront Landscape between Subjects of China,Japan and Britain 被引量:1
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作者 金华 金东来 王卓 《Journal of Landscape Research》 2012年第2期12-17,共6页
In order to explore the cultural value of waterfront in urban landscape,from the perspective of cross-cultural comparison psychology,the subjects from Britain,Japan and China have been surveyed to obtain their cogniti... In order to explore the cultural value of waterfront in urban landscape,from the perspective of cross-cultural comparison psychology,the subjects from Britain,Japan and China have been surveyed to obtain their cognitive structure and behavior on waterfront landscape.Based on the comparison of quantitative statistic results of life value,cognitive structure of waterfront space,and water-loving,a quantitative analysis has been conducted on the relevance between each factor by using Quantification Theory III.Then,it has analyzed the types and purpose of behavior in waterfront space,and the influence brought by cultural value difference. 展开更多
关键词 WATERFRONT landscape COGNITIVE structure BEHAVIOR CROSS-CULTURAL comparison
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Economic Competitiveness of China and the US:Comparison,Dynamic Change and Global Position 被引量:2
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作者 倪鹏飞 王海波 《China Economist》 2017年第4期2-31,共30页
Research of competitiveness of China and the United States is of great significance to enhancing China's economic competitiveness and achieving the objective of national rejuvenation. By creating a competitiveness fr... Research of competitiveness of China and the United States is of great significance to enhancing China's economic competitiveness and achieving the objective of national rejuvenation. By creating a competitiveness framework and a system of heterogeneous indicators, this paper investigates the competitiveness of China and the US in terms of current status, historic change and global environment. Our research led to the following findings: core factors determine the level of competitiveness for China and the US; the national competitiveness of both countries is evolving towards structural homogeneity; and China and the US lead most countries in many common areas. China has the potential to overtake the US in competitiveness in the future. We suggest that China increase its competitiveness by promoting its advantages, addressing its weaknesses and focusing on core areas. 展开更多
关键词 national competitiveness comparison between China and the US factor eterogeneity
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采用ISSR评价东北地区不同滑菇栽培品种性状
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作者 韩闯 王凤利 +3 位作者 岳欣 赵彦姝 张景文 戴肖东 《中国瓜菜》 北大核心 2026年第1期134-140,共7页
为明确东北地区滑菇主栽品种的生物学特性与遗传背景,选取当地11个滑菇主栽品种,通过菌丝形态观察、ISSR分子标记分析以及农法栽培试验,系统评价其栽培性状和遗传性状。结果表明,11个滑菇品种ISSR比对整体具有良好的遗传多样性,遗传相... 为明确东北地区滑菇主栽品种的生物学特性与遗传背景,选取当地11个滑菇主栽品种,通过菌丝形态观察、ISSR分子标记分析以及农法栽培试验,系统评价其栽培性状和遗传性状。结果表明,11个滑菇品种ISSR比对整体具有良好的遗传多样性,遗传相似系数为0.74时聚为3簇,其中罗2023单独分支。早壮、罗2023、吉滑1号和日滑199这4个品种在各项测试中表现突出,菌丝长速快(≥0.42 cm·d^(-1)),遗传差异较大,长满袋时间短(≤25 d),出现首个菇蕾时间早(≤80 d),前2潮次产量高(≥290 g·袋^(-1)),且子实体色泽鲜亮、抗性强。综上,早壮、罗2023、吉滑1号和日滑199这4个品种兼具早生性、高产性与环境适应性,可作为东北低温寒区农法栽培的早生型重点栽培品种。 展开更多
关键词 滑菇 品种比较 ISSR标记 产量
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