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基于Tv-SECOND的自动驾驶场景下的3D目标检测
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作者 魏海跃 杨奎河 毕江峰 《无线电通信技术》 北大核心 2024年第4期823-830,共8页
针对自动驾驶场景中复杂环境下的3D目标检测任务,特别是远距离和遮挡条件下,为提高模型的检测准确率,在SECOND的基础上提出了Tv-SECOND两阶段算法。该算法提出一种基于Transformer架构的提案框特征提取模块,并在传统体素特征编码基础上... 针对自动驾驶场景中复杂环境下的3D目标检测任务,特别是远距离和遮挡条件下,为提高模型的检测准确率,在SECOND的基础上提出了Tv-SECOND两阶段算法。该算法提出一种基于Transformer架构的提案框特征提取模块,并在传统体素特征编码基础上提出可变形的体素特征编码模块。在KITTI数据集上进行测试,结果显示,所提出的算法相比SECOND在远距离和遮挡严重的情况下分别提高了7.49%、9.72%。同时与其他先进的两阶段方法相比,检测精度有不同程度的提升,证明了Tv-SECOND算法的有效性。新算法能够建立特征之间的依赖关系,聚合周边广域的上下文信息,增强模型的学习推理能力,有效提升了模型在远距离和遮挡的情况下的检测性能。 展开更多
关键词 自动驾驶 3D目标检测 TRANSFORMER second
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The influence of wing morphology upon intraspecific divergence in birds: A global study of subspecies richness
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作者 Haiying Fan Weibin Guo +3 位作者 Buge Lin Zhiqing Hu Changcao Wang Shaobin Li 《Avian Research》 SCIE CSCD 2024年第2期196-201,共6页
Since the time of Darwin,subspecies have been recognized as an initial stage in the evolution of species.However,the impact of dispersal on subspecies richness in birds globally has received little attention,despite d... Since the time of Darwin,subspecies have been recognized as an initial stage in the evolution of species.However,the impact of dispersal on subspecies richness in birds globally has received little attention,despite dispersal being a key factor in determining the rate of evolution and playing a significant role in evolutionary divergence.Therefore,it is important to conduct a comprehensive study to address this issue.In this study,we aimed to assess the association between subspecies richness(measured by the number of subspecies)and dispersal ability(measured by the hand-wing index)on a global scale,using a dataset of over 7000 bird species.Our results revealed a negative correlation between dispersal ability and the number of subspecies,without any quadratic correlation.The wing is a crucial phenotypic trait for birds,and the concept of subspecies is important in speciation theory and conservation biology.Therefore,our findings not only enhance our understanding of the association between avian morphological traits and evolutionary divergence but also have implications for the conservation of avian species diversity. 展开更多
关键词 Dispersal Gene flow Hand-wing index Subspecies richness
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Spontaneous Abortions in the Second Trimester of Pregnancy: Research and Analysis of Factors Associated at Laquintinie Hospital in Douala
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作者 Henri Essome Moustapha Bilkissou +13 位作者 Merlin Boten Bounyom Sandrine Ngoumi Ingrid Doriane Ofakem Ilick Astrid Ndolo Kondo Fulbert Mangala Nkwele Michel Roger Ekono Alphonse Ngalame Nyong Robert Tchounzou Junie Ngaha Yaneu Marga Vanina Ngono Akam Gervais Mounchikpou Ngouhouo Grâce Tocki Toutou Théophile Nana Njamen Pascal Foumane 《Open Journal of Obstetrics and Gynecology》 2024年第8期1130-1143,共14页
Introduction: Spontaneous abortion of the second trimester is an interruption of pregnancy with complete expulsion or not of the product of conception between 15 and 28 weeks of pregnancy without any maneuvers. The ob... Introduction: Spontaneous abortion of the second trimester is an interruption of pregnancy with complete expulsion or not of the product of conception between 15 and 28 weeks of pregnancy without any maneuvers. The objective of our study was to determine the factors associated with second trimester spontaneous abortions at Laquintinie Hospital in Douala. Methodology for this purpose: We conducted a case-control study from January to May 2019 on pregnant women who may or may not have had spontaneous second trimester abortions. Results: In total we recorded 1609 pregnancies and recruited 184 patients, including 46 cases and 138 controls;which gave a frequency of spontaneous abortion in the second trimester of pregnancy of 2.85%. A correlative analysis showed that spontaneous abortions in the second trimester were associated with housewife status (OR = 2.89;CI = 1.21 - 6.79;p = 0.010), gestation > 5 (OR = 4.09;CI = 1.02 - 17.66;p = 0.040), multiparity (OR = 3.81;CI = 1.59 - 9.16;p = 0.002), history of endouterine maneuvers (OR = 5.64;CI = 2.43 - 13 .03;p = 0.000), malaria in pregnancy (OR = 3.99;CI = 1.1 - 14.76;p = 0.030), incompleteness on the second trimester ultrasound (OR = 2.37;CI = 1.18 - 4.70;p = 0.010), jolts when traveling (OR = 46.04;CI = 17.29 - 123.66;p = 0.000), long car journeys (OR = 7.05;CI = 1.99 - 27.77;p = 0.000). After logistic regression eliminating the confounding factors, only the following were associated with abortions: Multiparity (OR = 13.90;CI = 2.96 - 65.18;p = 0.000), endo uterine maneuvers (OR = 3.69;CI = 1. 01 - 13.44;p = 0.047), jolts when traveling (OR = 72.63;CI = 19.47 - 270.96;p = 0.000), long car journeys (OR = 15.41;CI = 2.7 - 85, 95;p = 0.000). Conclusion: Our study reveals that a set of factors contribute to the occurrence of spontaneous abortions in the second trimester of pregnancy in our context. 展开更多
关键词 Spontaneous Abortion second Trimester Associated Factors Laquintinie
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Understanding the catalytic performance and deactivation behaviour of second-promoter doped Pt/WO_(χ)/γ-Al_(2)O_(3) catalysts in the glycerol hydrogenolysis for selective and cleaner production of 1,3-propanediol
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作者 Rafik Rajjak Shaikh Sittichai Damruang +2 位作者 Rais Ahmad Khan Supareak Praserthdam Piyasan Praserthdam 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期486-507,共22页
The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the ca... The selective aqueous-phase glycerol hydrogenolysis is a promising reaction to produce commercially useful 1,3-propanediol(1,3-PDO).The Pt-WOx bifunctional catalyst can catalyse the glycerol hydrogenol-ysis but the catalyst deactivation via sintering,metal leaching,and coking can predominantly occur in the aqueous phase reaction.In this work,the effect of reaction temperature,pressure and second promoter(Cu,Fe,Rh,Mn,Re,Ru,Ir,Sn,B,and P)on catalytic performance and deactivation behaviour of Pt/WOx/-Al2O3 was investigated.When doped with Rh,Mn,Re,Ru,Ir,B,and P,the second promoter boosts catalytic activity by promoting great dispersion of Pt on support and increasing Pt surface area.The increased Bronsted acid sites lead to selective synthesis of 1,3-PDO than 1,2-propanediol(1,2-PDO).The characterization studies of fresh and spent catalysts reveal that the main cause of catalyst deactivation is the Pt sintering,as interpreted based on XRD,CO chemisorption,and TEM analyses.The Pt sintering is affected depending on the second promoter that can either or reduce the interaction between Pt,WO_(χ)/γ and Al_(2)O_(3).As an electron acceptor of Pt in Pt/WO_(χ)/γ-Al_(2)O_(3),Re and Mn as second promoters resulted in increased Pt^(2+) on the catalytic surface,which strengthens the contact between Pt andγ-Al_(2)O_(3) and WO_(χ),resulting in a decrease in Pt sintering.The metal leaching and coking are not affected by the presence of second promoter.The catalyst modified with a second promoter possesses improved catalytic activity and 1,3-PDO production,however the stability continues to remain a challenge.The present work unrav-elled the determining parameters of catalytic activity and deactivation,thus providing a promising pro-tocol toward effective catalysts for glycerol hydrogenolysis. 展开更多
关键词 Glycerol hydrogenolysis 1 3-PROPANEDIOL Metal-support interaction second promoter Liquid phase Catalyst deactivation
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Boosting rate performance of layered lithium-rich cathode materials by oxygen vacancy induced surface multicomponent integration
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作者 Youyou Fang Yuefeng Su +7 位作者 Jinyang Dong Jiayu Zhao Haoyu Wang Yun Lu Bin Zhang Hua Yan Feng Wu Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期250-262,共13页
The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(... The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(LLO)materials inherently excel.However,these materials face practical challenges,such as low initial Coulombic efficiency,inferior cycle/rate performance,and voltage decline during cycling,which limit practical application.Our study introduces a surface multi-component integration strategy that incorporates oxygen vacancies into the pristine LLO material Li1.2Mn_(0.6)Ni_(0.2)O_(2).This process involves a brief citric acid treatment followed by calcination,aiming to explore rate-dependent degradation behavior.The induced surface oxygen vacancies can reduce surface oxygen partial pressure and diminish the generation of O_(2)and other highly reactive oxygen species on the surface,thereby facilitating the activation of Li ions trapped in tetrahedral sites while overcoming transport barriers.Additionally,the formation of a spinel-like phase with 3D Li+diffusion channels significantly improves Li^(+)diffusion kinetics and stabilizes the surface structure.The optimally modified sample boasts a discharge capacity of 299.5 mA h g^(-1)at a 0.1 C and 251.6 mA h g^(-1)at a 1 C during the initial activation cycle,with an impressive capacity of 222.1 mA h g^(-1)at a 5 C.Most notably,it retained nearly 70%of its capacity after 300 cycles at this elevated rate.This straightforward,effective,and highly viable modification strategy provides a crucial resolution for overcoming challenges associated with LLO materials,making them more suitable for practical application. 展开更多
关键词 Lithium-ion battery Layered lithium rich cathode Surface multicomponent integration Rate-dependent degradation and Li^(+) diffusion kinetics
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Effect of Six Bacterial Strains on the Activity of Second Instar Larvae and Egg Hatching of Meloidogyne incognita
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作者 Jie LIU Li HE +4 位作者 Zixuan WANG Jianqing MA Xiaolong TONG Dandan CAO Gangyong ZHAO 《Plant Diseases and Pests》 2024年第5期15-18,共4页
[Objectives]The paper was to screen effective biocontrol strains against Meloidogyne incognita.[Methods]The effect of six bacterial strains sourced from the research group s strain library on the activity of second in... [Objectives]The paper was to screen effective biocontrol strains against Meloidogyne incognita.[Methods]The effect of six bacterial strains sourced from the research group s strain library on the activity of second instar larvae of M.incognita,as well as on egg hatching,was evaluated.[Results]The treatment of fermentation supernatant derived from the X-2 strain exhibited a pronounced lethal effect on M.incognita,with a corrected mortality rate reaching 97%within 72 h.Additionally,this treatment significantly inhibited egg hatching,achieving an inhibition rate of 94.69%at a 20-fold dilution.The strain was identified as Bacillus velezensis,belonging to the genus Bacillus,and was designated as RKN1111.[Conclusions]This study presents alternative strains and a theoretical framework for the biological control of M.incognita. 展开更多
关键词 Meloidogyne incognita Bacterial strain second instar larvae Egg hatching
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Researching Creativity in Second Language Acquisition:Book Review
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作者 SHEN Rong-xi ZENG Hai-xiang 《Journal of Literature and Art Studies》 2024年第3期215-219,共5页
In the realm of psychology and language acquisition,the exploration of“individual differences”-encompassing attributes such as personality traits,motivation,and language aptitude-has long been a focal point of schol... In the realm of psychology and language acquisition,the exploration of“individual differences”-encompassing attributes such as personality traits,motivation,and language aptitude-has long been a focal point of scholarly investigation.Within this sphere,the book“Researching Creativity in Second Language Acquisition”by Ashleigh Pipes offers a fresh perspective on the role of creativity as a significant individual difference in Second Language Acquisition(SLA).Positioned against the backdrop of extensive empirical research on individual differences,this book stands out by focusing on the often overlooked aspect of creativity,which Pipes argues,holds paramount importance in SLA. 展开更多
关键词 second Language Acquisition(SLA) CREATIVITY
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Solution of the Matrix Second Semi-Tensor Product Equation A ∘ l X ∘ l B=C
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作者 Hao Zhang 《Journal of Applied Mathematics and Physics》 2024年第10期3261-3280,共20页
In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time,... In this paper, the solution of the matrix second semi-tensor product equation A∘lX∘lB=Cis studied. Firstly, the solvability of the matrix-vector second semi-tensor product equation is investigated. At the same time, the compatibility conditions, the sufficient and necessary conditions and the specific solution methods for the matrix solution are given. Secondly, we further consider the solvability of the second semi-tensor product equation of the matrix. For each part, several examples are given to illustrate the validity of the results. 展开更多
关键词 Matrix Equation The second Semi-Tensor Product Compatibility Condition Sufficient and Necessary Conditions VECTORIZATION
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Review and Analysis: Evaluation of the Impacts and Consequences of Using Agricultural Herbicides as Military Chemical Weapons in Second Indochina War
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作者 David R. Speidel Kenneth R. Olson 《Open Journal of Soil Science》 2024年第8期471-498,共28页
The legacy of the human misery caused by the application of the herbicides including Agent Purple and Agent Orange contaminated with unknown amounts of dioxin TCDD and Agent Blue, the arsenic-based herbicide, sprayed ... The legacy of the human misery caused by the application of the herbicides including Agent Purple and Agent Orange contaminated with unknown amounts of dioxin TCDD and Agent Blue, the arsenic-based herbicide, sprayed over the jungles, rice fields, and hamlets of Vietnam is still haunting us today. Why did this happen? Could it have been prevented? Was it necessary United States military strategy? Was it an intentional decision to inflict this blight on the enemy soldiers and the Vietnamese, Cambodian, and Laotian civilians, to poison their land and cause generations of harm? Alternatively, was it an unpreventable accident in the march of military history? What patterns in the U.S. government’s thought process could be identified as the cause, which led to the decision to use these herbicides as tactical chemical weapons? If the introduction of herbicide (chemical) weapons had not been made, would the outcome of the Vietnam War and the Secret Wars in Laos and Cambodia have been any different? The objective of this treatise is to outline the role of world events and backgrounds and the role of the leaders, U.S. military, CIA, USDA, U.S. State Department, the U.S. President appointed Ambassadors to Vietnam and Laos, chemical companies, and President Diệm’s Republic of Vietnam (RVN) government and military. Their collective advice led to the decision to use herbicides as military and environmental chemical weapons in the Second Indochina War. Were the National interests achieved by U.S. military strategy in the RVN using herbicide weapons worth the long-term environmental and human health consequences in Vietnam, Cambodia, and Laos? Did it impact the outcome of the Second Indochina War? 展开更多
关键词 second Indochina War Cambodia Laos South Vietnam Vietnam War Tactical Herbicides Agent Blue Agent Orange Agent Purple Dioxin TCDD Arsenic
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Analysis of an Output-Oriented Teaching Method in College English under the Second Language Acquisition Theory
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作者 Ying Li 《Journal of Contemporary Educational Research》 2024年第10期35-39,共5页
In the context of economic globalization,English has become increasingly essential for students’communication and professional activities,necessitating higher proficiency in speaking and listening.The theory of secon... In the context of economic globalization,English has become increasingly essential for students’communication and professional activities,necessitating higher proficiency in speaking and listening.The theory of second language acquisition posits that college English teaching can purposefully guide students’learning and facilitate unconscious language acquisition.By integrating an output-oriented teaching method,students are provided with opportunities to practice and apply English,thereby addressing the traditional issue of“separation of learning and use.”This paper examines the application value of the output-oriented teaching method in college English under the second language acquisition theory and proposes several strategies to enhance college English classroom teaching.The goal is to develop students’linguistic competence and improve their practical English skills. 展开更多
关键词 second language acquisition College English Output-oriented teaching
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RICHARD MILLE 人体工学 现代设计进化论
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作者 Chaos 《钟表》 2024年第5期32-33,共2页
RICHARD MILLE理查米尔腕表与众不同的本质就在于其精密复杂的机械结构、美学设计和服贴手腕的人体工学造型,如同佩戴者的第二层肌肤,轻便、纤薄、运动感十足的表体线条。人体工学作为一个独立学科,满打满算也只有不到50年时间,虽然称... RICHARD MILLE理查米尔腕表与众不同的本质就在于其精密复杂的机械结构、美学设计和服贴手腕的人体工学造型,如同佩戴者的第二层肌肤,轻便、纤薄、运动感十足的表体线条。人体工学作为一个独立学科,满打满算也只有不到50年时间,虽然称不上历史悠久,但是它从人自身出发,在以人为主体的前提下研究人们的一切生活、生产活动中综合分析的新思路,正是顺应着社会发展的潮流和实际生活中的最高应用准则。 展开更多
关键词 人体工学 美学设计 运动感 rich 佩戴者 应用准则 独立学科
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RICHARD MILLE 产品永远的核心竞争力
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作者 Chaos 《钟表》 2024年第4期24-25,共2页
2024年的摩根史坦利钟表行业报告中,RICHARDMILLE理查米尔以第六名的位置继续保持着业内领先的地位,市场份额更是从前一年的2.8%增长到了3.1%。然而分析其背后真正的核心推力,当仁不让地来自于这一现代高级钟表品牌有着执着推进、且目... 2024年的摩根史坦利钟表行业报告中,RICHARDMILLE理查米尔以第六名的位置继续保持着业内领先的地位,市场份额更是从前一年的2.8%增长到了3.1%。然而分析其背后真正的核心推力,当仁不让地来自于这一现代高级钟表品牌有着执着推进、且目标清晰的长期产品规划与策略一一即轻便、抗震、符合人体工程学、高科技材质。 展开更多
关键词 核心竞争力 钟表行业 人体工程学 rich 市场份额 ARD
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RICHARD MILLE 红土之王的腕表进化史
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作者 Chaos 《钟表》 2024年第3期24-25,共2页
谈起网球,拉斐尔·纳达尔自然是21世纪最闪亮的明星之一,23年的职业生涯中,他斩获了22个大满贯冠军,从飘逸的西班牙少年到如今永远的红土之王,他的粉丝早已遍及全世界。RICHARDMILLE理查米尔的创始人Richard Mille先生也是粉丝中的... 谈起网球,拉斐尔·纳达尔自然是21世纪最闪亮的明星之一,23年的职业生涯中,他斩获了22个大满贯冠军,从飘逸的西班牙少年到如今永远的红土之王,他的粉丝早已遍及全世界。RICHARDMILLE理查米尔的创始人Richard Mille先生也是粉丝中的一员,早在2008年,他就开始接触纳达尔,那时的纳达尔还是一个拒绝在赛场上戴表的人,在他印象中手表总是很重,打球的时候会觉得不舒适。随着双方的友谊逐渐加深,纳达尔成为了理查米尔的品牌大使,推出了共同参与设计的腕表作品,并最终成就了一个经典的腕表系列,在腕表世界中,这也是一桩妙事。 展开更多
关键词 纳达尔 拉斐尔 rich 理查 米尔 职业生涯 腕表 粉丝
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RICHARD MILLE追求极致再上层楼
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作者 Chaos 《钟表》 2024年第2期24-25,共2页
日前,摩根士丹利(Morgan Stanley)和瑞士LuxeConsult公司联合发布了2024瑞士钟表产业年度报告,整个钟表行业在2023年有了明显的增长,实现了创纪录的267亿瑞士法郎的销售额,其中255亿瑞士法郎归因于腕表销售。其中,四大独立奢侈腕表品牌R... 日前,摩根士丹利(Morgan Stanley)和瑞士LuxeConsult公司联合发布了2024瑞士钟表产业年度报告,整个钟表行业在2023年有了明显的增长,实现了创纪录的267亿瑞士法郎的销售额,其中255亿瑞士法郎归因于腕表销售。其中,四大独立奢侈腕表品牌ROLEX劳力士、PATEK PHILIPPE百达翡丽、AUDEMARS PIGUET爱彼和RICHARD MILLE理查米尔的市场份额增长到43.9%,与2019年新冠疫情前的36.9%相比,这种增长趋势尤其明显。 展开更多
关键词 摩根士丹利 钟表行业 瑞士法郎 rich 年度报告 腕表 劳力士
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A Review of Research on Second Language Acquisition from a Positive Psychology Perspective
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作者 Yanhui Wu 《Journal of Contemporary Educational Research》 2024年第6期189-193,共5页
This paper reviews the research on second language acquisition from the perspective of positive psychology.First,it introduces the background and purpose of the study and discusses the significance of the application ... This paper reviews the research on second language acquisition from the perspective of positive psychology.First,it introduces the background and purpose of the study and discusses the significance of the application of positive psychology in the field of language acquisition.Then,the basic theories of positive psychology,including the core concepts and principles of positive psychology,are summarized.Subsequently,the theory of second language acquisition is defined and outlined,including the definition,characteristics,and related developmental theories of second language acquisition.On this basis,the study of second language acquisition from the perspective of positive psychology is discussed in detail.By combing and synthesizing the literature,this paper summarizes the current situation and trend of second language acquisition research under the perspective of positive psychology and puts forward some future research directions and suggestions. 展开更多
关键词 Positive psychology second language acquisition Language learning motivation Positive emotion Positive mindset
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Research on the Application of Second Language Acquisition Theory in College English Speech Teaching
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作者 Hui Zhang 《Journal of Contemporary Educational Research》 2024年第3期173-178,共6页
The teaching of English speeches in universities aims to enhance oral communication ability,improve English communication skills,and expand English knowledge,occupying a core position in English teaching in universiti... The teaching of English speeches in universities aims to enhance oral communication ability,improve English communication skills,and expand English knowledge,occupying a core position in English teaching in universities.This article takes the theory of second language acquisition as the background,analyzes the important role and value of this theory in English speech teaching in universities,and explores how to apply the theory of second language acquisition in English speech teaching in universities.It aims to strengthen the cultivation of English skilled talents and provide a brief reference for improving English speech teaching in universities. 展开更多
关键词 second language acquisition theory Teaching English speeches in universities Practical strategies
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Research on Practical Teaching of Ideological and Political Courses in Colleges and Universities and Collaborative Education in the Second Classroom
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作者 Luhua Xiao Pingping Liu Zimeng Li 《Journal of Contemporary Educational Research》 2024年第1期214-220,共7页
In today’s society,the need for talent training is of utmost importance due to rapid development.To achieve high-quality talent training,we need to focus on building a collaborative education mechanism.Practical teac... In today’s society,the need for talent training is of utmost importance due to rapid development.To achieve high-quality talent training,we need to focus on building a collaborative education mechanism.Practical teaching and the second classroom,which serve as important carriers of educational talents,must align their educational goals and complement each other.This article explores the collaborative education mechanism of the second classroom and practical teaching for the ideological and political courses in colleges and universities.It proposes reasonable construction measures to provide some guidelines for teaching work. 展开更多
关键词 Colleges and universities Ideological and political courses Practical teaching second classroom Collaborative education
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Split Addition of Nitrogen-Rich Substrate at Thermophilic and Mesophilic Stages of Composting: Effect on Green House Gases Emission and Quality of Compost
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作者 Boakye Acheampong Kodwo Miezah +2 位作者 Enoch Bessah Benedicta Essel Ayamba Francis Kemausour 《Open Journal of Soil Science》 2024年第2期133-158,共26页
Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed ... Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed the split-additions of nitrogen-rich substrate to composting materials and their effect on GHGs emissions as well as the quality of the composts. Nitrogen-rich substrates formulated from pig and goat manure were co-composted with MSW for a 12-weeks period by split adding at mesophilic (˚C) and thermophilic (>50˚C) stages in five different treatments. Representative samples from the compost were taken from each treatment for physicochemical, heavy metals and bacteriological analysis. In-situ CH<sub>4</sub>, CO<sub>2</sub>, N<sub>2</sub>O gas emissions were also analyzed weekly during composting. It was observed that all the treatments showed significant organic matter decomposition, reaching thermophilic temperatures in the first week of composting. The absence affects the suitable agronomic properties. All nitrogen-rich substrate applied at thermophilic stage (Treatment two) recorded the highest N, P and K concentrations of 1.34%, 0.97% and 2.45%, respectively with highest nitrogen retention. In terms of GHG emissions, CO<sub>2</sub> was highest at the thermophilic stage when N-rich substrate was added in all treatment, while CH<sub>4</sub> was highest in the mesophilic stage with N-rich substrate addition. N<sub>2</sub>O showed no specific trend in the treatments. Split addition of the N-rich substrate for co-composting of MSW produced compost which is stable, has less nutrient loss and low GHG emissions. Split addition of a nitrogen-rich substrate could be an option for increasing the fertilizer value of MSW compost. 展开更多
关键词 COMPOST Nitrogen-rich Substrate THERMOPHILIC MESOPHILIC Greenhouse Gas Emissions
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The Convergence Rate of Fréchet Distribution under the Second-Order Regular Variation Condition
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作者 Xilai Dai 《Journal of Applied Mathematics and Physics》 2024年第5期1597-1605,共9页
In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order ... In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order regular variation condition. 展开更多
关键词 Convergence Rate second-Order Regular Variation Condition Fréchet Distribution Extreme Value Index
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Neighborhood diversity structure and neighborhood species richness effects differ across life stages in a subtropical natural secondary forest 被引量:1
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作者 Haonan Zhang Shuifei Chen +5 位作者 Xiao Zheng Xiaomin Ge Yao Li Yanming Fang Peng Cui Hui Ding 《Forest Ecosystems》 SCIE CSCD 2022年第6期790-801,共12页
Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interact... Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interactions among individual plants,the local diversity spatial structure in secondary forest and the feedback effects of neighborhood diversity on natural regeneration remain unclear,and this may be the key to properly understand the mechanisms of natural secondary forest species diversity recovery.To this end,this study established a dynamic plot in a rehabilitated secondary forest after disturbance and conducted a comprehensive survey of 68,336 individual plants with repeated measurements at 5-year interval to assess the characteristics of neighborhood diversity structure across life history stages and link the neighborhood species richness(NSR)effect translated by species interactions at species diversity structure with individual trees recruitment/mortality in secondary forest regeneration.The results showed that,compared with tropical and temperate natural forests,a higher proportion of diversity accumulators and a lower proportion of repellers in subtropical secondary forests resulted in neighborhood diversity structures characterized by heterospecific or high-diversity patches,which are beneficial to the maintenance or restoration of biodiversity.As an important supplement to the research on the relationship between diversity and productivity,our findings show a positive diversity-survival relationship in subtropical secondary forests.Importantly,we observed that the neighborhood diversity structure exhibited a trend of accumulator-dominated to neutral-dominant changes with life stage from sapling to adult,which,in turn,determined the direction and strength of NSR effects on recruitment/mortality.Specifically,diverse local neighborhoods at a later successional stage characterized with‘neutral’species-species interactions can act as a‘welfare net’by offering favorable microhabitats for the most vulnerable recruitments or saplings,i.e.,the NSR effects that promoted individual recruitment/survival in our study.These results not only enrich our understanding of the biodiversity-productivity-survival relationship but also highlight the importance of retaining latesuccessional species of native trees in intensive forest production or in situ conservation policies. 展开更多
关键词 secondary forest restoration Individual species area relationship Diversity accumulator species Neighborhood species richness effect Life history stages Heterospecific crowding
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