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A Bayesian multi-model inference methodology for imprecise momentindependent global sensitivity analysis of rock structures
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作者 Akshay Kumar Gaurav Tiwari 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期840-859,共20页
Traditional global sensitivity analysis(GSA)neglects the epistemic uncertainties associated with the probabilistic characteristics(i.e.type of distribution type and its parameters)of input rock properties emanating du... Traditional global sensitivity analysis(GSA)neglects the epistemic uncertainties associated with the probabilistic characteristics(i.e.type of distribution type and its parameters)of input rock properties emanating due to the small size of datasets while mapping the relative importance of properties to the model response.This paper proposes an augmented Bayesian multi-model inference(BMMI)coupled with GSA methodology(BMMI-GSA)to address this issue by estimating the imprecision in the momentindependent sensitivity indices of rock structures arising from the small size of input data.The methodology employs BMMI to quantify the epistemic uncertainties associated with model type and parameters of input properties.The estimated uncertainties are propagated in estimating imprecision in moment-independent Borgonovo’s indices by employing a reweighting approach on candidate probabilistic models.The proposed methodology is showcased for a rock slope prone to stress-controlled failure in the Himalayan region of India.The proposed methodology was superior to the conventional GSA(neglects all epistemic uncertainties)and Bayesian coupled GSA(B-GSA)(neglects model uncertainty)due to its capability to incorporate the uncertainties in both model type and parameters of properties.Imprecise Borgonovo’s indices estimated via proposed methodology provide the confidence intervals of the sensitivity indices instead of their fixed-point estimates,which makes the user more informed in the data collection efforts.Analyses performed with the varying sample sizes suggested that the uncertainties in sensitivity indices reduce significantly with the increasing sample sizes.The accurate importance ranking of properties was only possible via samples of large sizes.Further,the impact of the prior knowledge in terms of prior ranges and distributions was significant;hence,any related assumption should be made carefully. 展开更多
关键词 Bayesian inference Multi-model inference statistical uncertainty Global sensitivity analysis(GsA) Borgonovo’s indices Limited data
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Transitivity Analysis of the Energy in China’s New Era
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作者 SHAN Ting WANG Yu 《Journal of Literature and Art Studies》 2024年第2期170-176,共7页
At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environme... At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environment has become a global issue that cannot be ignored in today’s era.Therefore,from the perspective of the ecological philosophy of Diversity&Harmony as well as Interaction&Co-existence,this paper will conduct ecological discourse analysis on the Energy in China’s New Era based on the transitivity system of systemic-functional grammar,and use the Corpus analysis software UAM Corpus Tool 3.3x to label and make statistics on the transitivity system,aiming to explore the distribution characteristics of the transitivity system in this white paper.Through the transitivity analysis of the white paper,this study helps readers to have a deeper understanding of the positive significance contained in the white paper.To a certain extent,it enables readers at home and abroad to understand China’s stance on energy issues and the positive image of China in energy ecology.It also awaken readers’awareness of environmental protection and acquire good habits of resource conservation to be in harmony between human and nature for sustainable development. 展开更多
关键词 TRANsITIvITY Ecological discourse analysis Energy in China’s new era
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Discourse Analysis of the Belt and Road Initiative From the Perspective of Central Asian Countries: A Case Study of the Republic of Kazakhstan
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作者 CHEN Jia LIU Shumin +1 位作者 FU Da’an SHAO Di 《Journalism and Mass Communication》 2024年第2期96-100,共5页
This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initi... This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initiative(BRI)in Central Asian countries.Through detailed analysis of policy documents,media reports,and public discussions in Central Asian countries,this paper reveals how the BRI constructs specific social practices,discourse events,and textual meanings within these nations.The findings indicate that through this global development strategy,China has not only strengthened its economic ties with Central Asian countries but has also exerted profound influences on political,cultural,and social levels. 展开更多
关键词 Belt and Road Initiative Central Asian countries discourse analysis Norman Fairclough’s three-dimensional model
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Conceptual Analysis of Self-Management in Patients with Hypertension
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作者 Li Yang Yutian Hao +4 位作者 Liling Zhong Shilin Xu Saiqiong Zhong Yanying Lu Hui Liu 《Journal of Clinical and Nursing Research》 2024年第5期356-368,共13页
Objective:To clarify the concept of self-management in hypertensive patients by analyzing the definition,attributes,and measurement tools through a literature review.Methods:An Internet-based search of the databases w... Objective:To clarify the concept of self-management in hypertensive patients by analyzing the definition,attributes,and measurement tools through a literature review.Methods:An Internet-based search of the databases was conducted using Academic Search Complete,Medical Line,CINAHL,Health Source:Nursing/Scholarly Edition,and Google Scholar.In the search process,keywords or free text were combined by using Boolean operators,with the search terms“self of management”or“self-management,”“concept*analysis”or“concept*definition,”and Walker and Avant’s concept analysis method was used.Results:Analysis of relevant literature summarized the conceptual attributes of self-management in hypertensive patients as the active participation of patients in the treatment process;the presence of interaction provided by patients and health care providers;the use of certain health management tools;and the aim of maintaining and improving the health status and living capacity of hypertensive patients.Conclusion:The concept of self-management for hypertensive patients was clarified,which helps to promote the application of hypertensive self-management in clinical work and improve outcomes and quality of life for patients with hypertension. 展开更多
关键词 HYPERTENsION sELF-MANAGEMENT Concept analysis Walker and Avant’s concept analysis method
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Shear wave splitting analysis of local earthquakes from dense arrays in Shimian,Sichuan 被引量:2
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作者 Sha Liu Baofeng Tian 《Earthquake Science》 2023年第1期52-63,共12页
The Shimian area of Sichuan sits at the junction of the Bayan Har block.Sichuan-Yunnan rhombic block,and Yangtze block,where several faults intersect.This region features intense tectonic activity and frequent earthqu... The Shimian area of Sichuan sits at the junction of the Bayan Har block.Sichuan-Yunnan rhombic block,and Yangtze block,where several faults intersect.This region features intense tectonic activity and frequent earthquakes.In this study,we used local seismic waveform data recorded using dense arrays deployed in the Shimian area to obtain the shear wave splitting parameters at 55 seismic stations and thereby determine the crustal anisotropic characteristics of the region.We then analyzed the crustal stress pattern and tectonic setting and explored their relationship in the study area.Although some stations returned a polarization direction of NNW-SSE.a dominant polarization direction of NW-SE was obtained for the fast shear wave at most seismic stations in the study area.The polarization directions of the fast shear wave were highly consistent throughout the study-area.This orientation was in accordance with the direction of the regional principal compressive stress and parallel to the trend of the Xianshuihe and Daliangshan faults.The distribution of crustal anisotropy in this area was affected by the regional tectonic stress field and the fault structures.The mean delay time between fast and slow shear waves was 3.83 ms/km.slightly greater than the values obtained in other regions of Sichuan.This indicates that the crustal media in our study area had a high anisotropic strength and also reveals the influence of tectonic complexity resulting from the intersection of multiple faults on the strength of seismic anisotropy. 展开更多
关键词 shear wave splitting polarization direction of the fast shear wave regional principal compressive stress dense array Citation:Liu s and Tian BF(2023).shear wave splitting analysis of local earthquakes from dense arrays in shimian sichuan.
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基于注意力机制的轻量化YOLO v5s蓝莓检测算法 被引量:3
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作者 刘拥民 张炜 +2 位作者 麻海志 刘原 张毅 《河南农业科学》 北大核心 2024年第3期151-157,共7页
为实现自然环境下蓝莓的精确快速检测,在YOLO v5s的基础上提出了一种结合轻量级网络和注意力机制的改进算法。首先,在主干网络和检测头的位置去除了最大目标检测层的结构,因而降低模型的参数量,增强模型对小目标的检测能力。其次,将MHSA... 为实现自然环境下蓝莓的精确快速检测,在YOLO v5s的基础上提出了一种结合轻量级网络和注意力机制的改进算法。首先,在主干网络和检测头的位置去除了最大目标检测层的结构,因而降低模型的参数量,增强模型对小目标的检测能力。其次,将MHSA(Multi‐head self‐attention,多头自注意力)替换了SPPF(Spatial pyramid pooling‐fast,快速空间金字塔池化)前面的C3模块,使模型学习到更全面的特征表示,增强模型对蓝莓图像中复杂空间关系和上下文信息的理解能力。最后,在C3模块中加入了S-PSA(Sequential polarized self‐attention,顺序极化自注意力),以便模型能够更好地捕捉特征图中相邻区域之间的上下文依赖关系。结果表明,改进后的YOLO v5s算法对成熟、半成熟和未成熟蓝莓的检测精度分别提升1.2、4.4、2.6百分点,平均精度提升2.7百分点,模型参数量减少76.0%。与当前主流轻量化目标检测模型相比,改进后的模型性能更加优越,能为自然环境下蓝莓采摘机器人视觉系统提供一种有效的方案。 展开更多
关键词 蓝莓检测 YOLO v5s 轻量级网络 注意力机制 多头自注意力
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A Comprehensive Bibliometric Analysis of China’s Free Trade Zones:Status and Evolutionary Trends
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作者 HUANG Lixia XU Miaoling 《Chinese Business Review》 2023年第3期127-140,共14页
The China free trade zone,crucial for advancing a new open economy,has gained significant attention lately.We analyzed 885 papers from Peking University Core and CSSCI journals(2012-2023)using CiteSpace for visualizat... The China free trade zone,crucial for advancing a new open economy,has gained significant attention lately.We analyzed 885 papers from Peking University Core and CSSCI journals(2012-2023)using CiteSpace for visualization.Our research results indicate that the literature on China’s free trade zone peaked with 171 articles in 2015,and gradually returned to an average of 45 articles per year.The main research focuses in this field include“institutional innovation”,“negative list”,“financial innovation”,“financial openness”,“opening up to the outside world”,and“economic growth”.In addition,cutting-edge analysis indicates that“dual circulation”and“blockchain”are future research trends.The main authors of the literature include Yang Bin,Zhu Xiaolin,Yuan Bo,Li Meng,Zhao Liang,and others.Their affiliated institutions,research institutes,and universities have not yet formed a clear core circle of authors;The top three research institutions with the highest number of publications are the International Trade and Economic Cooperation Research Institute of the Ministry of Commerce,Kaiyuan Law School of Shanghai Jiao Tong University,and the Comprehensive Research Institute of the Free Trade Zone of Sun Yatsen University.This article delves into the current hot topics and progress in the research of China’s free trade zones,providing important references and inspirations for future scholars in this field. 展开更多
关键词 China’s free trade zone bibliometric analysis CITEsPACE
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A Survey of English Translation Studies of Lu You’s Poetry Based on the Data Analysis of Domestic Academic Journals (2001-2022)
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作者 Dongfang Chen Jiesen Ma 《Open Journal of Applied Sciences》 2023年第6期847-857,共11页
This article presents a comprehensive analysis of the current state of research on the English translation of Lu You’s poetry, utilizing a data sample comprising research papers published in the CNKI Full-text Databa... This article presents a comprehensive analysis of the current state of research on the English translation of Lu You’s poetry, utilizing a data sample comprising research papers published in the CNKI Full-text Database from 2001 to 2022. Employing rigorous longitudinal statistical methods, the study examines the progress achieved over the past two decades. Notably, domestic researchers have displayed considerable interest in the study of Lu You’s English translation works since 2001. The research on the English translation of Lu You’s poetry reveals a diverse range of perspectives, indicating a rich body of scholarship. However, several challenges persist, including insufficient research, limited translation coverage, and a noticeable focus on specific poems such as “Phoenix Hairpin” in the realm of English translation research. Consequently, there is ample room for improvement in the quality of research output on the English translation of Lu You’s poems, as well as its recognition within the academic community. Building on these findings, it is argued that future investigations pertaining to the English translation of Lu You’s poetry should transcend the boundaries of textual analysis and encompass broader theoretical perspectives and research methodologies. By undertaking this shift, scholars will develop a more profound comprehension of Lu You’s poetic works and make substantive contributions to the field of translation studies. Thus, this article aims to bridge the gap between past research endeavors and future possibilities, serving as a guide and inspiration for scholars to embark on a more nuanced and enriching exploration of Lu You’s poetry as well as other Chinese literature classics. 展开更多
关键词 Lu You’s Poetry English Translation studies Data analysis Translation Criticism
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基于轻量化YOLO v8s-GD的自然环境下百香果快速检测模型
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作者 罗志聪 何陈涛 +2 位作者 陈登捷 李鹏博 孙奇燕 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期291-300,共10页
为了提高百香果检测精度,并将深度学习模型部署在移动平台上,实现快速实时推理,本文提出一种基于改进YOLO v8s的轻量化百香果检测模型(YOLO v8s-GD)。使用聚集和分发机制(GD)替换颈部特征融合网络,提高模型对百香果图像特征信息跨层融... 为了提高百香果检测精度,并将深度学习模型部署在移动平台上,实现快速实时推理,本文提出一种基于改进YOLO v8s的轻量化百香果检测模型(YOLO v8s-GD)。使用聚集和分发机制(GD)替换颈部特征融合网络,提高模型对百香果图像特征信息跨层融合能力和模型泛化能力;通过基于层自适应幅度的剪枝(LAMP)修剪模型,损失一定精度换取减小模型体积,减少模型参数量,以实现在嵌入式设备上快速检测;运用知识蒸馏学习策略弥补因剪枝而损失的检测精度,提高模型检测性能。实验结果表明,对于自然环境下采集的百香果数据集,改进后模型参数量和内存占用量相比原YOLO v8s基线模型分别降低63.88%和62.10%,精确率(Precision)和平均精度(AP)相较于原模型分别提高0.9、2.3个百分点,优于其他对比模型。在Jetson Nano和Jetson Tx2嵌入式设备上实时检测帧率(FPS)分别为5.78、19.38 f/s,为原模型的1.93、1.24倍。因此,本文提出的改进后模型能够有效检测复杂环境下百香果目标,为实际场景中百香果自动采摘等移动端检测设备部署和应用提供理论和技术支持。 展开更多
关键词 百香果 YOLO v8s 轻量化 检测模型 聚集和分发机制
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基于改进YOLO v8s的羊只行为识别方法 被引量:1
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作者 王旺 王福顺 +4 位作者 张伟进 刘红达 王晨 王超 何振学 《农业机械学报》 EI CAS CSCD 北大核心 2024年第7期325-335,344,共12页
羊只站立、行走、采食等日常行为与其健康状况密切相关,高效、准确的羊只行为识别有助于疾病检测,对实现羊只健康预警具有重要意义。针对目前羊只多行为识别检测大多基于传感器等接触式设备,羊只活动受限,行为具有局限性,且群体养殖环境... 羊只站立、行走、采食等日常行为与其健康状况密切相关,高效、准确的羊只行为识别有助于疾病检测,对实现羊只健康预警具有重要意义。针对目前羊只多行为识别检测大多基于传感器等接触式设备,羊只活动受限,行为具有局限性,且群体养殖环境下,羊只行为多样、场景复杂、存在遮挡等造成的行为识别精度低等问题,提出了一种基于改进YOLO v8s的羊只行为识别方法。首先,引入SPPCSPC空间金字塔结构增强了模型的特征提取能力,提升了模型的检测精度。其次,新增P2小目标检测层,增强了模型对小目标的识别和定位能力。最后,引入多尺度轻量化模块PConv和EMSConv,在保证模型识别效果的同时,降低了模型参数量和计算量,实现了模型轻量化。实验结果表明,改进YOLO v8s模型对羊只站立、行走、采食、饮水、趴卧行为平均识别精度分别为84.62%、92.58%、87.54%、98.13%和87.18%,整体平均识别精度为90.01%。与Faster R-CNN、YOLO v5s、YOLO v7、YOLO v8s模型相比,平均识别精度分别提高12.03、3.95、1.46、2.19个百分点。研究成果可为羊只健康管理和疾病预警提供技术支撑。 展开更多
关键词 行为识别 YOLO v8s 轻量化
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主观幸福感研究的发展历程与趋向——基于CiteSpace V的文献计量分析
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作者 肖童 李俊逸 +2 位作者 梁宏飞 艾勇军 雷轩 《科学与管理》 2024年第4期43-51,共9页
随着新型城镇化和幸福城市建设的推进,国民幸福感的提升成为政府和社会各界的关注焦点,学界也涌现大量学术成果。然而,现有相关综述性文献存在时效性不足、研究尺度过于聚焦等问题。基于Web of Science数据库,利用信息可视化软件CiteSpa... 随着新型城镇化和幸福城市建设的推进,国民幸福感的提升成为政府和社会各界的关注焦点,学界也涌现大量学术成果。然而,现有相关综述性文献存在时效性不足、研究尺度过于聚焦等问题。基于Web of Science数据库,利用信息可视化软件CiteSpace V对1990—2023年主观幸福感领域的英语文献进行共现分析、合作分析和聚类分析等,并结合传统文献研究方法,全面客观探析主观幸福感研究的发展脉络和趋向。研究发现:(1)1990年至今,主观幸福感研究经历了学科拓展、微观空间转向、深入研究和多元化发展三个阶段,多学科交叉、微观空间、人本主义为显著特征;(2)高产作者凸显而核心作者群缺乏,作者跨界合作度低,高产作者主要来自美国、西班牙;(3)研究机构合作广泛但强度不足,尚未形成核心研究群,高产机构集中在美国、加拿大、英国等。目前,主观幸福感研究发展已相对成熟,后续研究可着重关注微观邻里空间这一分析单元,以弱势群体为重点研究对象,借助新兴测度工具,不断完善主观幸福感影响机制和效应的理论框架。 展开更多
关键词 主观幸福感 文献计量分析 Citespace v 研究热点
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基于CiteSpace v.6.2.R6的数学类课程思政研究可视化分析
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作者 陈莹 陶诗仪 +3 位作者 龚书琪 陈诗怡 余言 高仕龙 《黑龙江科学》 2024年第13期68-72,共5页
随着高校课程思政的深入开展,如何将思政教育融入到课程教学中成为高等教育关注的焦点。以数学类课程为例,通过CiteSpace v.6.2.R6软件对数学类课程思政相关研究进行可视化分析,探讨数学类课程思政相关研究的学术合作、研究热点、主题... 随着高校课程思政的深入开展,如何将思政教育融入到课程教学中成为高等教育关注的焦点。以数学类课程为例,通过CiteSpace v.6.2.R6软件对数学类课程思政相关研究进行可视化分析,探讨数学类课程思政相关研究的学术合作、研究热点、主题演化等方面情况。研究结果表明,目前数学类课程思政研究主要集中在思政元素挖掘、教学改革、教学设计等领域,并存在跨学科合作的趋势。如何将数学课程与思政教育有机结合起来仍需进一步探索与实践。数学类课程思政相关研究仍不够深入系统,大部分研究停留在案例分析与经验总结层面,缺乏理论支撑与更科学的研究方法。未来研究可进一步优化分析工具,提升图谱的可视化效果与分析效率,也可探索对其他分析方法与工具的应用。 展开更多
关键词 Citespace v.6.2.R6 课程思政 数学教学 可视化分析
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Benthodytes occidentpalauta sp.nov.,a new species of deep-sea holothuroid(Elasipodida:Psychropotidae)from the west of Kyushu-Palau Ridge in the Western Pacific Ocean
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作者 Chongzhen YUAN Chunsheng WANG Dongsheng ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期252-262,共11页
Benthodytes occidentpalauta sp.nov.was collected from the Kyushu-Palau Ridge at a depth of 5481 m in 2021.This new species is characterized by a gelatinous body wall,violet skin,six pairs of dorsal papillae,and a roug... Benthodytes occidentpalauta sp.nov.was collected from the Kyushu-Palau Ridge at a depth of 5481 m in 2021.This new species is characterized by a gelatinous body wall,violet skin,six pairs of dorsal papillae,and a rough mid-ventral surface without tube feet.The dorsal deposits are rod-shaped and tripartite.Two types of papillae deposits as crosses with four arms with central bipartite apophyses.Ventral deposits are rods.Tentacle ossicles are rod-shaped with end protrusions.Gonad deposits are rodshaped,tripartite,and cross-shaped.The phylogenetic analyses based on cytochrome oxidase subunit 1(COI)and 16S individually and a concatenated dataset of COI and 16S genes of this species support that B.occidentpalauta sp.nov.belongs to Benthodytes. 展开更多
关键词 HOLOTHUROIDEA Benthodytes cytochrome oxidase subunit 1(COI) 16s phylogenetic analysis
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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved s1 selection method Maize population Genetic gain Comparative analysis
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Proximity to corridors benefits bird communities in vegetated interrow vineyards in Mendoza, Argentina
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作者 Andrea Paula Goijman Agustín Zarco 《Avian Research》 SCIE CSCD 2024年第2期147-155,共9页
Management under ecological schemes and increasing habitat heterogeneity,are essential for enhancing biodiversity in vineyards.Birds provide several contributions to agriculture,for example pest control,recreation and... Management under ecological schemes and increasing habitat heterogeneity,are essential for enhancing biodiversity in vineyards.Birds provide several contributions to agriculture,for example pest control,recreation and enhancing human mental health,and have intrinsic value.Birds are also ideal model organisms because they are easy to survey,and species respond differently to agricultural land use at different scales.Vegetated borders of crops are key for many species of birds,and distance to the border have been found to be an important factor in vineyard-dominated agroecosystems.We evaluate if there are differences in the bird assemblage,between the interior compared to borders within vineyards,using a hierarchical community occupancy model.We hypoth-esized that occupancy of birds is greater in environments with greater heterogeneity,which in this study was considered to be contributed by the proximity to vegetated corridors.We expected that vineyard borders close to corridors will have higher bird occupancy than the center of the vineyard.The research was conducted in three vineyards with biodiversity-friendly management practices,in Gualtallary,Mendoza,Argentina.Bird surveys were conducted over three breeding seasons from 2018 to 2020.Occupancy and richness of the bird community was more closely associated with the borders adjacent to the corridors than with the interior of the vineyards,as we initially predicted,although the assemblage of birds did not differ much.More than 75%of the registered species consume exclusively or partially invertebrates.Biodiversity-friendly management and ecological schemes,together with vegetated corridors provide multiple benefits for biodiversity conservation.These ap-proaches not only minimize the use of agrochemicals but also prioritize soil cover with spontaneous vegetation,which supports a diverse community of insectivorous bird species,potentially contributing to pest control. 展开更多
关键词 Avian Bayesian analysis Field scale agroecosystem Management Multi-species occupancy model Nature’s contributions to people
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Spatio-temporal Variation Characteristics of Extreme Climate Events and Their Teleconnections to Large-scale Ocean-atmospheric Circulation Patterns in Huaihe River Basin,China During 1959–2019
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作者 YAO Tian ZHAO Qiang +6 位作者 WU Chuanhao HU Xiaonong XIA Chuan'an WANG Xuan SANG Guoqiang LIU Jian WANG Haijun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期118-134,共17页
Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of... Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation indices.The results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing trend.Furthermore,all extreme temperature indices show significant mutations during 1959-2019.Spatially,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of HRB.Arctic oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation indices.AO and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature range.Extreme warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern HRB.In contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB. 展开更多
关键词 extreme climate indices sen’s slope variation mutation test atmospheric circulation indices Pearson’s correlation analysis Huaihe River Basin(HRB) China
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Evolution and Governance of the Structure of Marine Economic Networks in China’s Coastal Areas: Based on Sea-related A-share Listed Companies
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作者 LI Bo CAO Gai 《Chinese Geographical Science》 SCIE CSCD 2024年第5期899-916,共18页
Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linka... Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to emerge.The construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic development.Employing data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its governance.The following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is significant.On this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing bodies.By clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy. 展开更多
关键词 marine economic network sea-related A-share listed companies social network analysis(sNA) network governance China’s coastal areas
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全国市场VS区域市场:碳市场有效性的差异、成因及其对策 被引量:1
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作者 唐德祥 廖盛兴 《工业技术经济》 CSSCI 北大核心 2024年第1期112-121,共10页
对碳市场有效性进行测度、把握碳市场运行效率,有利于进一步推动碳交易机制优化和效率提升。本文以全国碳排放权交易市场及8个区域试点碳市场为研究对象,以2021年7月16日至2023年6月16日碳配额成交均价为样本,运用结构突变检验法与重标... 对碳市场有效性进行测度、把握碳市场运行效率,有利于进一步推动碳交易机制优化和效率提升。本文以全国碳排放权交易市场及8个区域试点碳市场为研究对象,以2021年7月16日至2023年6月16日碳配额成交均价为样本,运用结构突变检验法与重标极差分析法对各个碳市场整体与阶段运行效率进行测度。研究结果表明:全国碳市场整体运行效率偏低,仅第一阶段达到了弱式有效水平;在区域试点碳市场中北京碳市场达到弱式有效,若考虑结构突变点时,则上海、广东、湖北、深圳和重庆碳市场达到阶段性弱式有效。在此基础上,进一步剖析了全国碳市场有效性较低的影响因素,并有针对性地提出对策建议。 展开更多
关键词 碳市场 分形市场假说 结构突变 R/s分析法 HURsT指数 碳配额
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基于S7-300PLC的净水厂V型滤池控制系统设计思路探究
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作者 姚家泰 《中国设备工程》 2024年第S02期133-135,共3页
净水厂是城市供水的主要来源,净水厂出厂水质的安全可靠是确保安全饮用水的首要任务。滤池是净水厂工艺流程中水处理关键环节,对出厂水质产生直接影响。随着科技的发展和进步,实现净水厂滤池自动化高效运行,本文围绕基于S7-300 PLC的净... 净水厂是城市供水的主要来源,净水厂出厂水质的安全可靠是确保安全饮用水的首要任务。滤池是净水厂工艺流程中水处理关键环节,对出厂水质产生直接影响。随着科技的发展和进步,实现净水厂滤池自动化高效运行,本文围绕基于S7-300 PLC的净水厂V型滤池控制系统设计展开一系列的探讨,分析研究了净水厂V型滤池在正常过滤过程和反冲洗功能的难点和解决方法,并实现净水厂V型滤池在正常过滤过程和反冲洗功能控制系统精确控制,经过三亚市某水厂的实际运行检验,系统可靠稳定,同时使得净水厂出厂水质符合生活饮用水标准,希望能给净水厂V型滤池控制系统设计上带来一些帮助。 展开更多
关键词 净水厂 v型滤池 s7-300 PLC 控制系统
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Distribution, Mobility, and Health Risks Assessment of Trace Metals in River Sediments from Intense Agricultural Activity Areas in West Africa
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作者 Ahbeauriet Ahmed Ouattara Maley-Pacôme Soro +2 位作者 Albert Brou Kouadio Horo Koné Albert Trokourey 《Journal of Materials Science and Chemical Engineering》 2024年第8期12-42,共31页
The economy of West African countries is mainly based on agriculture. However, the trace metal(loid)s contamination status in rivers is relatively unknown in the region. In this work, 45 surface sediments collected fr... The economy of West African countries is mainly based on agriculture. However, the trace metal(loid)s contamination status in rivers is relatively unknown in the region. In this work, 45 surface sediments collected from the Bandama, Comoé, and Bia Rivers in south and south eastern Côte d’Ivoire (West Africa), were analyzed for total metal concentrations and chemical speciation. The results showed that the river sediments were considerably contaminated by Cd and moderately contaminated by As, Cu, Pb, and Zn. Significant spatial variations were observed among the stations but not between the rivers. Metals Cd and Cu were likely to cause more ecological risks. The speciation analysis unravelled that the metal(loid)s partitioned mainly in the residual fraction, with the potential mobile fraction varying from 14% to 28%. The study calls for establishment of strict policies relative to the application of fertilizers and agrochemicals and mining activities to protect the environment and human health risks. 展开更多
关键词 River sediment Trace Metal (Loid)s Multivariate analysis Potential Ecological Risk Assessments sequential Extraction Geochemical Indices
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