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Optimized Target-AID system efficiently induces single base changes in zebrafish
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作者 Xiaochan Lu Yunxing Liu +3 位作者 Guanrong Yan Song Li Wei Qin Shuo Lin 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2018年第4期215-217,共3页
CRISPR-Cas system has been widely adapted as a platform for genome editing in various eukaryotic organisms, including zebrafish(Cong et al., 2013; Hwang et al., 2013). One of the important applications of CRISPR-Cas... CRISPR-Cas system has been widely adapted as a platform for genome editing in various eukaryotic organisms, including zebrafish(Cong et al., 2013; Hwang et al., 2013). One of the important applications of CRISPR-Cas9 system is to produce double-strand DNA breaks(DSBs) at targeted sites with guide RNA(gRNA). 展开更多
关键词 AID Optimized Target-AID system efficiently induces single base changes in zebrafish TARGET
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Two selenium tolerant Lysinibacillus sp. strains are capable of reducing selenite to elemental Se efficiently under aerobic conditions 被引量:8
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作者 Ju Zhang Yue Wang +4 位作者 Zongyuan Shao Jing Li Shuting Zan Shoubiao Zhou Ruyi Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第3期238-249,共12页
Microbes play important roles in the transport and transformation of selenium(Se) in the environment, thereby influencing plant resistance to Se and Se accumulation in plant. The objectives are to characterize the bac... Microbes play important roles in the transport and transformation of selenium(Se) in the environment, thereby influencing plant resistance to Se and Se accumulation in plant. The objectives are to characterize the bacteria with high Se tolerance and reduction capacity and explore the significance of microbial origins on their Se tolerance, reduction rate and efficiency. Two bacterial strains were isolated from a naturally occurred Se-rich soil at tea orchard in southern Anhui Province, China. The reduction kinetics of selenite was investigated and the reducing product was characterized using scanning electron microscopy and transmission electron microscopy-energy dispersive spectroscopy. The bacteria were identified as Lysinibacillus xylanilyticus and Lysinibacillus macrolides,respectively, using morphological, physiological and molecular methods. The results showed that the minimal inhibitory concentrations(MICs) of selenite for L. xylanilyticus and L. macrolides were 120 and 220 mmol/L, respectively, while MICs of selenate for L.xylanilyticus and L. macrolides were 800 and 700 mmol/L, respectively. Both strains aerobically reduced selenite with an initial concentration of 1.0 mmol/L to elemental Se nanoparticles(SeNPs) completely within 36 hr. Biogenic SeNPs were observed both inside and outside the cells suggesting either an intra-or extracellular reduction process. Our study implied that the microbes from Se-rich environments were more tolerant to Se and generally quicker and more efficient than those from Se-free habitats in the reduction of Se oxyanions. The bacterial strains with high Se reduction capacity and the biological synthesized Se NPs would have potential applications in agriculture, food, environment and medicine. 展开更多
关键词 SELENIUM TOLERANT bacteria SELENITE REDUCTION Nanoparticles REDUCTION rate REDUCTION efficiency Sources
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Feasibility of Tea Saponin-Enhanced Soil Washing in a Soybean Oil-Water Solvent System to Extract PAHs/Cd/Ni Efficiently from a Coking Plant Site 被引量:6
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作者 YE Mao SUN Mingming +8 位作者 XIE Shanni LIU Kuan FENG Yanfang ZHAO Yu WAN Jinzhong HU Feng LI Huixin ZONG Lianggang JIANG Xin 《Pedosphere》 SCIE CAS CSCD 2017年第3期452-464,共13页
Mixed contaminated brownfield sites have brought serious risks to human health and environmental safety. With the purpose of removing polycyclic aromatic hydrocarbons (PAHs) and heavy metals from a coking plant site... Mixed contaminated brownfield sites have brought serious risks to human health and environmental safety. With the purpose of removing polycyclic aromatic hydrocarbons (PAHs) and heavy metals from a coking plant site, an innovative technology for ex-situ washing was developed in the present work. The combination of 15.0 mLL-1 soybean oil and 7.5 g L-1 tea saponin proved an effective method to extract co-pollutants from soil. After two consecutive washing cycles, the efficiency rates of removal for 3-, 4-, 5(+6)-ring, and total PAHs, Cd, and Ni were approximately 98.2%, 96.4%, 92.3%, 96.3%, 94.1%, and 89.4%, respectively. Meanwhile, as evaluated by Tenax extraction method and metal stability indices, the residual PAHs and heavy metals after consecutive washing mainly existed in the form with extremely low bioaccessibility in the soil. Thus, in the soil after two washing cycles, there appeared limited environmental transfer risk of co-pollutants. Moreover, a subsequent precipitation method with alkaline solution and PAH- degrading strain Sphingobium sp. PHE9 inoculation effectively removed 84.6%-100% of Cd, 82.5%-91.7% of Ni, and 92.6%-98.4% of PAHs from the first and second washing solvents. The recovered solvents also exhibited a high recycling effectiveness. Therefore, the combined cleanup strategy proposed in this study proved environmentally friendly, which also played a major role in risk assessment and marlagement in mixed polluted sites. 展开更多
关键词 DESORPTION mixed contaminated site partition index redistribution index removal efficiency sequential extraction Wenax extraction
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Discussion on How to Spread Campus Activities Efficiently in the New Media Era
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作者 LINLin 《外文科技期刊数据库(文摘版)教育科学》 2022年第11期021-024,共4页
School is an important place for teaching and educating people, and the spread of ideas, ideas and knowledge depends on the development of campus activities. The realization of efficient dissemination of campus activi... School is an important place for teaching and educating people, and the spread of ideas, ideas and knowledge depends on the development of campus activities. The realization of efficient dissemination of campus activities will help to enhance the function and value of school education and promote the common progress of teachers and students. In the new media era, great changes have taken place in peoples life, learning habits and reading styles. Campus activity communication also needs to keep pace with social development to achieve optimization and improvement. The article briefly introduces the "new media", and puts forward the idea of realizing the efficient communication of campus activities from the aspects of the form, content, operation mode, form and communication technology of the dissemination of information title, aiming to promote the effectiveness of public opinion propaganda in schools at all levels. 展开更多
关键词 new media era campus activities high efficiency SPREAD
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A new type of cementation flushing fluid for efficiently removing wellbore filter cake
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作者 Chen Erding Wang Chengwen Meng Renzhou 《Natural Gas Industry B》 2015年第5期455-460,共6页
For effectively removing the water-based drilling fluid filter cake and improving interfacial cementing strength and cementing quality,a new type of cementation flushing fluid(WD-C)was developed based on the strong fl... For effectively removing the water-based drilling fluid filter cake and improving interfacial cementing strength and cementing quality,a new type of cementation flushing fluid(WD-C)was developed based on the strong flushing principle of water soluble fiber and the oxygenolysis principle of filter cake.It is composed of 0.5%WF-H fiber,2.2%WF-O oxidant,0.35%FeSO_(4),1.8%KCl,3.0%swollen powder perlite and water with its density of 1.03 g/cm^(3).This cementation flushing fluid was systematically tested and evaluated in terms of its washing efficiency on the filter cake of water-based drilling fluid and its capacity to improve the bonding strength of cementation interface.In addition,an analysis was performed of its effect on the physical-chemical characteristics and the micro-structures of interfacial cements by means of infrared spectrum(IR),scanning electron microscope(SEM)and energy dispersive X-ray detector(EDS).It is shown that the new cementation flushing fluid presents excellent washing effect on water-based drilling fluid filter cake(with washing time within 10 min).The cement particles at the cemented interface can be hydrated normally,and hydrated calcium silicate gel,Ca(OH)_(2)and rod-shaped ettringite(AFt)crystal are generated and interwoven with each other.In this way,dense network structures are formed,so the bonding strength of the second cementing interface rises significantly,and then cementing quality is improved.Based on the research results,one more technology is set up for removing the water-based drilling fluid filter cake efficiently and improving the bonding strength of the second cementing interface. 展开更多
关键词 Flushing fluid Water-based drilling fluid Washing efficiency Filter cake Well cementing Interfacial cementation Cementing quality
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基于双流特征交叉融合Efficient Transformer的人脸表情识别
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作者 党宏社 孟饶辰 高宛蓉 《计算机工程与应用》 北大核心 2025年第15期251-257,共7页
面部表情识别在人机交互等现实应用中得到了越来越多的重视。为解决传统方法中由于类间相似性和类内差异引起的识别准确率低等问题,提出了一种双流特征交叉融合Efficient Transformer识别人脸表情的方法。使用IResNet50和MobileFaceNet... 面部表情识别在人机交互等现实应用中得到了越来越多的重视。为解决传统方法中由于类间相似性和类内差异引起的识别准确率低等问题,提出了一种双流特征交叉融合Efficient Transformer识别人脸表情的方法。使用IResNet50和MobileFaceNet分别提取人脸表情的图像和关键点的多尺度特征,同时采用通道注意力机制来增强关键特征并减少参数量;引入了交叉融合高效多头自注意力机制(cross fusion efficient multi-head self-attention,CFEMSA),对相同尺度的双流特征进行交叉融合,以突出面部显著特征;最后采用特征金字塔结构对不同尺度的交叉融合结果进行多尺度融合,以提高识别的准确性。提出的方法在RAF-DB、AffecNet-7和AffecNet-8数据集上的识别准确率分别为91.82%、67.46%和63.65%,实验结果证明该方法有效缓解了类间相似性和类内差异所引起的识别准确率低的问题。 展开更多
关键词 面部表情识别 Efficient Transformer 交叉融合 多尺度特征 特征融合
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YOLOv8-DEL:基于改进YOLOv8n的实时车辆检测算法研究 被引量:7
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作者 古佳欣 陈高华 张春美 《计算机工程与应用》 北大核心 2025年第1期142-152,共11页
车辆检测是智能交通系统和自动驾驶的重要组成部分。然而,实际交通场景中存在许多不确定因素,导致车辆检测模型的准确率低实时性差。为了解决这个问题,提出了一种快速准确的车辆检测算法——YOLOv8-DEL。使用DGCST(dynamic group convol... 车辆检测是智能交通系统和自动驾驶的重要组成部分。然而,实际交通场景中存在许多不确定因素,导致车辆检测模型的准确率低实时性差。为了解决这个问题,提出了一种快速准确的车辆检测算法——YOLOv8-DEL。使用DGCST(dynamic group convolution shuffle transformer)模块代替C2f模块来重构主干网络,以增强特征提取能力并使网络更轻量;添加的P2检测层能使模型更敏锐地定位和检测小目标,同时采用Efficient RepGFPN进行多尺度特征融合,以丰富特征信息并提高模型的特征表达能力;通过结合GroupNorm和共享卷积的优点,设计了一种轻量型共享卷积检测头,在保持精度的前提下,有效减少参数量并提升检测速度。与YOLOv8相比,提出的YOLOv8-DEL在BDD100K数据集和KITTI数据集上,mAP@0.5分别提高了4.8个百分点和1.2个百分点,具有实时检测速度(208.6 FPS和216.4 FPS),在检测精度和速度方面实现了更有利的折中。 展开更多
关键词 车辆检测 YOLOv8 DGCST Efficient RepGFPN 轻量级检测头
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DOGE改革下美国联邦政府采购的治理实验
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作者 赵勇 《中国招标》 2025年第3期14-22,共9页
美国联邦政府采购体系以其繁多的法律体系和复杂的监管框架著称。2025年,随着特朗普政府成立政府效率部门(Department of Government Efficiency,DOGE),美国联邦政府正在探索如何通过创新技术和优化流程提高政府效率和透明度。笔者希望... 美国联邦政府采购体系以其繁多的法律体系和复杂的监管框架著称。2025年,随着特朗普政府成立政府效率部门(Department of Government Efficiency,DOGE),美国联邦政府正在探索如何通过创新技术和优化流程提高政府效率和透明度。笔者希望通过对DOGE成立1个多月以来在推动美国联邦政府采购预算和监管模式的改革方面所采取的措施,探讨美国联邦政府采购的最新改革动向,包括预算削减与采购规模压缩、采购流程AI化、政府采购社会经济政策目标的调整、对采购组织机构和人员的影响、监管方式的改变,以及DOGE的法律与政治挑战、长期影响和示范效应。 展开更多
关键词 政府效率部门(Department of Government Efficiency DOGE) 技术赋能 制度困局 政府采购 治理实验
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FEV-YOLOv8n:轻量化安全帽佩戴检测方法 被引量:3
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作者 韩博 张婧婧 鲁子翱 《计算机测量与控制》 2025年第1期69-77,84,共10页
针对基线YOLOv8n检测算法结构较复杂以及现有的安全帽佩戴检测算法参数量和计算量较大,难以在终端部署等问题,提出一种基于FEV-YOLOv8n的轻量化检测模型;设计一种轻量级的FasterC2f模块改进YOLOv8n的骨干网络,实现网络的参数量和计算量... 针对基线YOLOv8n检测算法结构较复杂以及现有的安全帽佩戴检测算法参数量和计算量较大,难以在终端部署等问题,提出一种基于FEV-YOLOv8n的轻量化检测模型;设计一种轻量级的FasterC2f模块改进YOLOv8n的骨干网络,实现网络的参数量和计算量的降低;在FasterC2f模块中引入EMA注意力机制,融合空间依赖和位置信息,建立长短期的依赖关系,增强对目标表征的关注,以提高模型检测的精度;使用VoVGSCSP模块改进颈部网络,提高遮挡目标以及小目标的辨识度;实验结果表明,改进YOLOv8n模型map值为92.5%,相较于YOLOv8n算法,模型大小减少20%,计算量降低18.5%,参数量降低15.7%,为安全帽佩戴检测的轻量化研究提供理论参考。 展开更多
关键词 目标检测 安全帽 FasterC2f 轻量化 Efficient Multi-Scale Attention VoVGSCSP
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基于CNN和Efficient Transformer的多尺度遥感图像语义分割算法 被引量:1
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作者 张振利 胡新凯 +2 位作者 李凡 冯志成 陈智超 《浙江大学学报(工学版)》 北大核心 2025年第4期778-786,共9页
针对现有方法存在遥感图像的多尺度地物特征提取困难和目标边缘分割不准确的问题,提出新的语义分割算法.利用CNN和Efficient Transformer构建双编码器,解耦上下文信息和空间信息.提出特征融合模块加强编码器间的信息交互,有效融合全局... 针对现有方法存在遥感图像的多尺度地物特征提取困难和目标边缘分割不准确的问题,提出新的语义分割算法.利用CNN和Efficient Transformer构建双编码器,解耦上下文信息和空间信息.提出特征融合模块加强编码器间的信息交互,有效融合全局上下文信息和局部细节信息.构建分层Transformer结构提取不同尺度的特征信息,使编码器有效专注不同尺度的物体.提出边缘细化损失函数,缓解遥感图像目标边缘分割不准确的问题.实验结果表明,在ISPRS Vaihingen和ISPRS Potsdam数据集上,所提算法的平均交并比(MIoU)分别为72.45%和82.29%.在SAMRS数据集中的SOTA、SIOR和FAST子集上,所提算法的MIoU分别为88.81%、97.29%和86.65%,总体精度和平均交并比指标均优于对比模型.所提算法在各类不同尺度的目标上有较好的分割性能. 展开更多
关键词 遥感图像 语义分割 双编码器结构 特征融合 Efficient Transformer
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SEFormer:A Lightweight CNN-Transformer Based on Separable Multiscale Depthwise Convolution and Efficient Self-Attention for Rotating Machinery Fault Diagnosis 被引量:1
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作者 Hongxing Wang Xilai Ju +1 位作者 Hua Zhu Huafeng Li 《Computers, Materials & Continua》 SCIE EI 2025年第1期1417-1437,共21页
Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain limitations.Conversely,deep learning techniques have gained promine... Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain limitations.Conversely,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis efficiency.Recently,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault diagnosis.However,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative model.This complexity results in high computational costs and limited industrial applicability.To tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault diagnosis.First,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration signals.Then,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global perspective.Finally,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and Transformer.This study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment. 展开更多
关键词 CNN-Transformer separable multiscale depthwise convolution efficient self-attention fault diagnosis
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Boosting high-performance in Zr-rich side protonic solid oxide electrolysis cells by optimizing functional interlayer 被引量:1
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作者 Chunmei Tang Ning Wang +3 位作者 Sho Kitano Hiroki Habazaki Yoshitaka Aoki Siyu Ye 《Green Energy & Environment》 SCIE EI CAS 2025年第1期150-160,共11页
Protonic solid oxide electrolysis cells(P-SOECs)are a promising technology for water electrolysis to produce green hydrogen.However,there are still challenges related key materials and anode/electrolyte interface.P-SO... Protonic solid oxide electrolysis cells(P-SOECs)are a promising technology for water electrolysis to produce green hydrogen.However,there are still challenges related key materials and anode/electrolyte interface.P-SOECs with Zr-rich electrolyte,called Zr-rich side P-SOECs,possess high thermodynamically stability under high steam concentrations but the large reaction resistances and the current leakage,thus the inferior performances.In this study,an efficient functional interlayer Ba_(0.95)La_(0.05)Fe_(0.8)Zn_(0.2)O_(3-δ)(BLFZ)in-between the anode and the electrolyte is developed.The electrochemical performances of P-SOECs are greatly enhanced because the BLFZ can greatly increase the interface contact,boost anode reaction kinetics,and increase proton injection into electrolyte.As a result,the P-SOEC yields high current density of 0.83 A cm^(-2) at 600℃ in 1.3 Vamong all the reported Zr-rich side cells.This work not only offers an efficient functional interlayer for P-SOECs but also holds the potential to achieve P-SOECs with high performances and long-term stability. 展开更多
关键词 Functional interlayer Zr-rich side electrolyte Protonic solid oxide electrolysis cells Current density Faradaic efficiency
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基于EFN-YOLO的钢管表面缺陷检测
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作者 马自勇 屈言森 +2 位作者 马立东 张之腾 孔世武 《组合机床与自动化加工技术》 北大核心 2025年第1期195-200,共6页
针对目前钢管表面缺陷视觉检测方法存在小目标缺陷难以识别的问题,提出一种基于EFN-YOLO的缺陷实时检测方法。首先,结合NWD度量和Iou loss,提出改进型N-iou loss,增强小缺陷目标的感知能力;其次,采用Efficient Former特征提取模块嵌入... 针对目前钢管表面缺陷视觉检测方法存在小目标缺陷难以识别的问题,提出一种基于EFN-YOLO的缺陷实时检测方法。首先,结合NWD度量和Iou loss,提出改进型N-iou loss,增强小缺陷目标的感知能力;其次,采用Efficient Former特征提取模块嵌入主干网络融合局部和全局特征信息,提高对细小且聚集缺陷目标的识别能力;接着,采用轻量化C2f特征提取模块替换原Yolov5的C3层,降低模型的参数量和复杂度,丰富图像的梯度流信息;最后,结合现场采集的钢管表面缺陷图片,对检测方法进行试验验证。结果表明,相较于改进前检测方法的mAP值提升5.8%,有效提升钢管表面细小缺陷检测能力,且FPS达到31,完全满足工业现场实时检测要求。 展开更多
关键词 钢管 小目标缺陷 YOLOv5 N-iou loss efficient former 深度学习
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RoBERTa-GCN-EGPLinker中文实体关系联合抽取
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作者 冯甲 张仕斌 +3 位作者 闫丽丽 秦智 昌燕 吕智颖 《计算机技术与发展》 2025年第9期132-139,共8页
实体关系抽取是自然语言处理中的核心任务之一,旨在从文本中识别出实体及其之间的关系,生成实体关系三元组,为后续的数据分析和知识发现提供基础。随着中文语言的复杂性,尤其是在实体嵌套、关系重叠等问题上,中文实体关系抽取面临着诸... 实体关系抽取是自然语言处理中的核心任务之一,旨在从文本中识别出实体及其之间的关系,生成实体关系三元组,为后续的数据分析和知识发现提供基础。随着中文语言的复杂性,尤其是在实体嵌套、关系重叠等问题上,中文实体关系抽取面临着诸多挑战。传统方法在处理这些复杂语言现象时,常常受到语法结构和上下文信息捕捉不充分的限制。因此,如何提高中文实体关系抽取的精度和效率,成为了该领域研究的重点。为了解决这些问题,提出了一种基于RoBERTa-GCN-EGPLinker的中文实体关系联合抽取方法。该方法首先利用RoBERTa-wwm-ext模型对文本进行深度语义编码,结合中文依存分析工具LTP,提取文本的依存关系和句法结构信息。接着,通过构建图卷积神经网络(GCN)和语义邻接矩阵,进一步捕捉文本中的结构化信息。这种方法不仅能够有效处理实体之间的关系,还能在面对复杂语言现象时保持较高的抽取精度。实验结果表明,该方法在公开数据集CMeIE-V2和DuIE上具有显著的优势,能够提升中文实体关系抽取的精度与效率。 展开更多
关键词 实体关系抽取 中文文本 LTP工具 RoBERTa-wwm-ext 图卷积神经网络 Efficient Glob-alPointer模型
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MSFAFuse:基于多尺度特征信息与注意力机制的SAR和可见光图像融合模型
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作者 潘树焱 刘立群 《图学学报》 北大核心 2025年第2期300-311,共12页
针对单一成像原理得到的遥感图像无法提供丰富信息的问题,异源遥感图像融合技术应运而生。合成孔径雷达图像成像不受云层、天气等因素影响,但缺乏目视观测能力;可见光图像成像易受恶劣环境影响,但拥有直视效果及目标解译能力。将二者融... 针对单一成像原理得到的遥感图像无法提供丰富信息的问题,异源遥感图像融合技术应运而生。合成孔径雷达图像成像不受云层、天气等因素影响,但缺乏目视观测能力;可见光图像成像易受恶劣环境影响,但拥有直视效果及目标解译能力。将二者融合可以充分利用各自优势,得到包含更多特征信息并具有目视观测能力的高质量图像。为充分利用异源图像不同尺度特征,提出一种基于多尺度特征信息与注意力机制的SAR和可见光图像融合模型(MSFAFuse)。首先,引入鲁棒特征下采样组成特征提取部分,得到异源图像对应的多尺度特征。其次,使用特征增强模块来增强不同尺度异源特征中的结构特征及显著区域特征。然后,使用基于特征信息引导以及L1-Norm的双分支融合模块将得到的异源多尺度特征按尺度进行两两融合。最后,将不同尺度的融合结果输入图像重构模块,进行图像重建,最终获得融合图像。实验表明,MSFAFuse模型可以在保留更多细节及结构信息的同时平滑地增强突出特征。与现有融合方法相比,该模型在10种不同指标上实现了较好的效果,可以有效地融合可见光图像与SAR图像,为二者融合的发展提供了新思路,有助于推动未来遥感图像融合技术的发展。 展开更多
关键词 图像融合 多尺度特征 Efficient additive attention 遥感 深度学习
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Experimental realization to efficiently sort vector beams by polarization topological charge via Pancharatnam–Berry phase modulation 被引量:4
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作者 SHUIQIN ZHENG YING LI +6 位作者 QINGGANG LIN XUANKE ZENG GUOLIANG ZHENG YI CAI ZHENKUAN CHEN SHIXIANG XU DIANYUAN FAN 《Photonics Research》 SCIE EI 2018年第5期385-389,共5页
This paper reports the experimental realization of efficiently sorting vector beams by polarization topological charge (PTC). The PTC of a vector beam can be defined as the repetition number of polarization state ch... This paper reports the experimental realization of efficiently sorting vector beams by polarization topological charge (PTC). The PTC of a vector beam can be defined as the repetition number of polarization state change along the azimuthal axis, while its sign stands for the rotating direction of the polarization. Here, a couple of liquid crystal Pancharatnam-Berry optical dements (PBOEs) have been used to introduce conjugated spatial phase modulations for two orthogonal circular polarization states. Applying these PBOEs in a 4-foptical system, our experiments show the setup can work for PTC sorting with a separation efficiency of more than 58%. This work provides an effective way to decode information from different PTCs, which may be interesting in many fields, especially in optical communication. 展开更多
关键词 Experimental realization to efficiently sort vector beams polarization topological charge via Pancharatnam-Berry phase modulation
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Phosphorus acquisition,translocation,and redistribution in maize 被引量:2
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作者 Hui-Ling Guo Meng-Zhi Tian +1 位作者 Xian Ri Yi-Fang Chen 《Journal of Genetics and Genomics》 2025年第3期287-296,共10页
Phosphorus(P)is an essential nutrient for crop growth,making it important for maintaining food security as the global population continues to increase.Plants acquire P primarily via the uptake of inorganic phosphate(P... Phosphorus(P)is an essential nutrient for crop growth,making it important for maintaining food security as the global population continues to increase.Plants acquire P primarily via the uptake of inorganic phosphate(Pi)in soil through their roots.Pi,which is usually sequestered in soils,is not easily absorbed by plants and represses plant growth.Plants have developed a series of mechanisms to cope with P deficiency.Moreover,P fertilizer applications are critical for maximizing crop yield.Maize is a major cereal crop cultivated worldwide.Increasing its P-use efficiency is important for optimizing maize production.Over the past two decades,considerable progresses have been achieved in studies aimed at adapting maize varieties to changes in environmental P supply.Here,we present an overview of the morphological,physiological,and molecular mechanisms involved in P acquisition,translocation,and redistribution in maize and combine the advances in Arabidopsis and rice,to better elucidate the progress of P nutrition.Additionally,we summarize the correlation between P and abiotic stress responses.Clarifying the mechanisms relevant to improving P absorption and use in maize can guide future research on sustainable agriculture. 展开更多
关键词 Plant nutrient Phosphorus acquisition Phosphorus translocation Phosphorus-use efficiency Corn yield
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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001-2020 被引量:2
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作者 HE Chenyang WANG Yanjiao +1 位作者 YAN Feng LU Qi 《Journal of Geographical Sciences》 2025年第1期39-64,共26页
Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosyste... Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation. 展开更多
关键词 water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau
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Split nitrogen application increases maize root growth,yield,and nitrogen use efficiency under soil warming conditions 被引量:2
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作者 Zhenqing Xia Yuxiang Gong +3 位作者 Xiangyue Lyu Junchen Lin Yi Yang Haidong Lu 《The Crop Journal》 2025年第2期565-575,共11页
The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use e... The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress. 展开更多
关键词 Maize(Zea mays L.) Soil warming Split nitrogen application Root growth Nitrogen use efficiency Grain yield
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基于注意力-残差双特征流卷积神经网络的深度图帧内编码单元快速划分算法
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作者 贾克斌 吴岳珩 《北京工业大学学报》 北大核心 2025年第5期539-551,共13页
针对三维高效视频编码(three-dimensional high efficiency video coding,3D-HEVC)深度图编码单元(coding unit,CU)划分复杂度高的问题,提出一种基于卷积神经网络(convolutional neural networks,CNN)的算法来实现快速深度图帧内编码。... 针对三维高效视频编码(three-dimensional high efficiency video coding,3D-HEVC)深度图编码单元(coding unit,CU)划分复杂度高的问题,提出一种基于卷积神经网络(convolutional neural networks,CNN)的算法来实现快速深度图帧内编码。首先,提出一种具有3个分支的注意力-残差双特征流卷积神经网络(attention-residual bi-feature stream convolutional neural networks,ARBS-CNN)模型,其中基于残差模块(residual module,RM)和特征蒸馏(feature distill,FD)模块的2个分支用于提取全局图像特征,基于动态模块(dynamic module,DM)和卷积-卷积块注意力模块(convolutional-convolutional block attention module,Conv-CBAM)的分支用于提取局部图像特征;然后,将提取到的特征进行整合并输出,得到对深度图CU划分结构的预测;最后,将ARBS-CNN嵌入到3D-HEVC测试平台中,利用预测结果加速深度图帧内编码。与原始算法相比,提出的算法能在维持率失真性能几乎不受影响的条件下,平均减少74.2%的编码时间。实验结果表明,该算法能够在保持率失真性能的条件下,有效降低3D-HEVC的编码复杂度。 展开更多
关键词 三维高效视频编码(three-dimensional high efficiency video coding 3D-HEVC) 深度图 卷积神经网络(convolutional neural networks CNN) 编码单元(coding unit CU)划分 帧内编码 双特征流
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