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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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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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MKEAH:Multimodal knowledge extraction and accumulation based on hyperplane embedding for knowledge-based visual question answering
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作者 Heng ZHANG Zhihua WEI +6 位作者 Guanming LIU Rui WANG Ruibin MU Chuanbao LIU Aiquan YUAN Guodong CAO Ning HU 《虚拟现实与智能硬件(中英文)》 EI 2024年第4期280-291,共12页
Background External knowledge representations play an essential role in knowledge-based visual question and answering to better understand complex scenarios in the open world.Recent entity-relationship embedding appro... Background External knowledge representations play an essential role in knowledge-based visual question and answering to better understand complex scenarios in the open world.Recent entity-relationship embedding approaches are deficient in representing some complex relations,resulting in a lack of topic-related knowledge and redundancy in topic-irrelevant information.Methods To this end,we propose MKEAH:Multimodal Knowledge Extraction and Accumulation on Hyperplanes.To ensure that the lengths of the feature vectors projected onto the hyperplane compare equally and to filter out sufficient topic-irrelevant information,two losses are proposed to learn the triplet representations from the complementary views:range loss and orthogonal loss.To interpret the capability of extracting topic-related knowledge,we present the Topic Similarity(TS)between topic and entity-relations.Results Experimental results demonstrate the effectiveness of hyperplane embedding for knowledge representation in knowledge-based visual question answering.Our model outperformed state-of-the-art methods by 2.12%and 3.24%on two challenging knowledge-request datasets:OK-VQA and KRVQA,respectively.Conclusions The obvious advantages of our model in TS show that using hyperplane embedding to represent multimodal knowledge can improve its ability to extract topic-related knowledge. 展开更多
关键词 Knowledge-based visual question answering HYPERPLANE Topic-related
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PAL-BERT:An Improved Question Answering Model
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作者 Wenfeng Zheng Siyu Lu +3 位作者 Zhuohang Cai Ruiyang Wang Lei Wang Lirong Yin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2729-2745,共17页
In the field of natural language processing(NLP),there have been various pre-training language models in recent years,with question answering systems gaining significant attention.However,as algorithms,data,and comput... In the field of natural language processing(NLP),there have been various pre-training language models in recent years,with question answering systems gaining significant attention.However,as algorithms,data,and computing power advance,the issue of increasingly larger models and a growing number of parameters has surfaced.Consequently,model training has become more costly and less efficient.To enhance the efficiency and accuracy of the training process while reducing themodel volume,this paper proposes a first-order pruningmodel PAL-BERT based on the ALBERT model according to the characteristics of question-answering(QA)system and language model.Firstly,a first-order network pruning method based on the ALBERT model is designed,and the PAL-BERT model is formed.Then,the parameter optimization strategy of the PAL-BERT model is formulated,and the Mish function was used as an activation function instead of ReLU to improve the performance.Finally,after comparison experiments with traditional deep learning models TextCNN and BiLSTM,it is confirmed that PALBERT is a pruning model compression method that can significantly reduce training time and optimize training efficiency.Compared with traditional models,PAL-BERT significantly improves the NLP task’s performance. 展开更多
关键词 PAL-BERT question answering model pretraining language models ALBERT pruning model network pruning TextCNN BiLSTM
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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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Operational requirements analysis method based on question answering of WEKG
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作者 ZHANG Zhiwei DOU Yajie +3 位作者 XU Xiangqian MA Yufeng JIANG Jiang TAN Yuejin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期386-395,共10页
The weapon and equipment operational requirement analysis(WEORA) is a necessary condition to win a future war,among which the acquisition of knowledge about weapons and equipment is a great challenge. The main challen... The weapon and equipment operational requirement analysis(WEORA) is a necessary condition to win a future war,among which the acquisition of knowledge about weapons and equipment is a great challenge. The main challenge is that the existing weapons and equipment data fails to carry out structured knowledge representation, and knowledge navigation based on natural language cannot efficiently support the WEORA. To solve above problem, this research proposes a method based on question answering(QA) of weapons and equipment knowledge graph(WEKG) to construct and navigate the knowledge related to weapons and equipment in the WEORA. This method firstly constructs the WEKG, and builds a neutral network-based QA system over the WEKG by means of semantic parsing for knowledge navigation. Finally, the method is evaluated and a chatbot on the QA system is developed for the WEORA. Our proposed method has good performance in the accuracy and efficiency of searching target knowledge, and can well assist the WEORA. 展开更多
关键词 operational requirement analysis weapons and equipment knowledge graph(WEKG) question answering(QA) neutral network
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DPAL-BERT:A Faster and Lighter Question Answering Model
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作者 Lirong Yin Lei Wang +8 位作者 Zhuohang Cai Siyu Lu Ruiyang Wang Ahmed AlSanad Salman A.AlQahtani Xiaobing Chen Zhengtong Yin Xiaolu Li Wenfeng Zheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期771-786,共16页
Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering systems.However,with the constant evolution of algorithms,data,and computing power,the ... Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering systems.However,with the constant evolution of algorithms,data,and computing power,the increasing size and complexity of these models have led to increased training costs and reduced efficiency.This study aims to minimize the inference time of such models while maintaining computational performance.It also proposes a novel Distillation model for PAL-BERT(DPAL-BERT),specifically,employs knowledge distillation,using the PAL-BERT model as the teacher model to train two student models:DPAL-BERT-Bi and DPAL-BERTC.This research enhances the dataset through techniques such as masking,replacement,and n-gram sampling to optimize knowledge transfer.The experimental results showed that the distilled models greatly outperform models trained from scratch.In addition,although the distilled models exhibit a slight decrease in performance compared to PAL-BERT,they significantly reduce inference time to just 0.25%of the original.This demonstrates the effectiveness of the proposed approach in balancing model performance and efficiency. 展开更多
关键词 DPAL-BERT question answering systems knowledge distillation model compression BERT Bi-directional long short-term memory(BiLSTM) knowledge information transfer PAL-BERT training efficiency natural language processing
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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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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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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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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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ANSWER模型评估新疆咸水灌溉棉花产量与效益 被引量:5
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作者 张妮 左强 +2 位作者 石建初 许艳奇 吴训 《农业工程学报》 EI CAS CSCD 北大核心 2023年第2期78-89,共12页
利用咸水或微咸水进行农田灌溉是缓解中国新疆地区农业水资源供需矛盾从而保障当地棉花产业可持续发展的主要途径之一。为了明确不同咸水灌溉措施对棉花产量及经济效益的影响,该研究通过2 a的棉花膜下滴灌大田试验和文献检索获取了新疆... 利用咸水或微咸水进行农田灌溉是缓解中国新疆地区农业水资源供需矛盾从而保障当地棉花产业可持续发展的主要途径之一。为了明确不同咸水灌溉措施对棉花产量及经济效益的影响,该研究通过2 a的棉花膜下滴灌大田试验和文献检索获取了新疆9个不同试验地点的土壤、作物及灌溉等数据资料,评估作物产量-水盐胁迫响应分析模型(ANalytical Salt WatER,ANSWER)在新疆棉花产量评估中的适用性和可靠性,并结合经济收支平衡方法,模拟分析不同咸水灌溉措施(包括不同灌溉定额和灌溉水电导率的组合)对棉花产量与经济效益的影响。采用决定系数(R2)、均方根误差(root mean squared error,RMSE)、相对均方根误差(relative root mean squared error,RRMSE)评价模型精度。结果表明,在9个不同试验地点,ANSWER模型均可较准确地估算棉花的相对产量,其估算值与实测值之间的R^(2)≥0.54,RMSE≤0.14,RRMSE≤0.16;不同试验地点,优化获得的各个模型生物参数(与棉花根系吸水的水盐胁迫响应相关的参数)差异较小,变异系数的绝对值处于0.08~0.37之间;基于不同试验地点优化的各生物参数均值估算各地的棉花相对产量,其与实测值仍然吻合良好(R^(2)为0.59,RMSE为0.06,RRMSE为0.07);此外,当灌溉水电导率一定时,棉花净收益随灌溉定额增加呈先增后降的趋势,净收益达到峰值所需的灌溉定额随灌溉水电导率升高而迅速增加;当灌溉水电导率不大于10 dS/m时,通过加大供水量均可获得与淡水灌溉相当的净收益。研究可为新疆地区棉花产量与效益评估以及咸水资源合理开发利用提供理论依据。 展开更多
关键词 棉花 灌溉 模型 answer 咸水 产量 效益
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Analysis of community question-answering issues via machine learning and deep learning:State-of-the-art review 被引量:3
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作者 Pradeep Kumar Roy Sunil Saumya +2 位作者 Jyoti Prakash Singh Snehasish Banerjee Adnan Gutub 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期95-117,共23页
Over the last couple of decades,community question-answering sites(CQAs)have been a topic of much academic interest.Scholars have often leveraged traditional machine learning(ML)and deep learning(DL)to explore the eve... Over the last couple of decades,community question-answering sites(CQAs)have been a topic of much academic interest.Scholars have often leveraged traditional machine learning(ML)and deep learning(DL)to explore the ever-growing volume of content that CQAs engender.To clarify the current state of the CQA literature that has used ML and DL,this paper reports a systematic literature review.The goal is to summarise and synthesise the major themes of CQA research related to(i)questions,(ii)answers and(iii)users.The final review included 133 articles.Dominant research themes include question quality,answer quality,and expert identification.In terms of dataset,some of the most widely studied platforms include Yahoo!Answers,Stack Exchange and Stack Overflow.The scope of most articles was confined to just one platform with few cross-platform investigations.Articles with ML outnumber those with DL.Nonetheless,the use of DL in CQA research is on an upward trajectory.A number of research directions are proposed. 展开更多
关键词 answer quality community question answering deep learning expert user machine learning question quality
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Low-temperatures synthesis of CuS nanospheres as cathode material for magnesium second batteries 被引量:2
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作者 Qin Zhang Yaobo Hu +1 位作者 Jun Wang Fusheng Pan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第1期192-200,共9页
Rechargeable magnesium batteries(RMBs),as one of the most promising candidates for efficient energy storage devices with high energy,power density and high safety,have attracted increasing attention.However,searching ... Rechargeable magnesium batteries(RMBs),as one of the most promising candidates for efficient energy storage devices with high energy,power density and high safety,have attracted increasing attention.However,searching for suitable cathode materials with fast diffusion kinetics and exploring their magnesium storage mechanisms remains a great challenge.Cu S submicron spheres,made by a facile low-temperature synthesis strategy,were applied as the high-performance cathode for RMBs in this work,which can deliver a high specific capacity of 396mAh g^(-1)at 20 mA g^(-1) and a remarkable rate capacity of 250 m Ah g^(-1)at 1000 mA g^(-1).The excellent rate performance can be assigned to the nano needle-like particles on the surface of Cu S submicron spheres,which can facilitate the diffusion kinetics of Mg^(2+).Further storage mechanism investigations illustrate that the Cu S cathodes experience a two-step conversion reaction controlled by diffusion during the electrochemical reaction process.This work could make a contribution to the study of the enhancement of diffusion kinetics of Mg2+and the reaction mechanism of RMBs. 展开更多
关键词 Magnesium second batteries Cathode material CUS Submicron spheres Low-temperature synthesis.
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Temporal electric field of a helium plasma jet by electric field induced second harmonic(E-FISH)method 被引量:2
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作者 李旭 晋绍珲 +3 位作者 宋珂 聂兰兰 刘大伟 卢新培 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第1期43-52,共10页
Electric field is an important parameter of plasma,which is related to electron temperature,electron density,excited species density,and so on.In this work,the electric field of an atmospheric pressure plasma jet is d... Electric field is an important parameter of plasma,which is related to electron temperature,electron density,excited species density,and so on.In this work,the electric field of an atmospheric pressure plasma jet is diagnosed by the electric field induced second harmonic(E-FISH)method,and the time-resolved electric field under different conditions is investigated.When positive pulse voltage is applied,the electric field has a peak of about 25 kV cm-1at the rising edge of the voltage pulse.A dark channel is left behind the plasma bullet and the electric field in the dark channel is about 5 kV cm-1.On the other hand,when negative pulse voltage is applied,the electric field has a peak of-16 kV cm-1when the negative voltage is increased to-8 kV.A relatively bright channel is left behind the plasma head and the electric field in this relatively bright channel is about-6 kV cm-1.When the pulse rising time increases from 60 to 200 ns,the peak electric field at both the rising edge and the falling edge of the voltage decreases significantly.When 0.5%of oxygen is added to the main working gas helium,the peak electric field at the rising edge is only about 15 kV cm-1.On the other hand,when 0.5%nitrogen is added,the peak electric field increases especially at the falling edge of the voltage pulse,where it increases reversely from-12 to-16 kV cm-1(the minus sign only represents the direction of electric field). 展开更多
关键词 atmospheric pressure plasma jet electric field electric field induced second harmonic
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Expert Recommendation in Community Question Answering via Heterogeneous Content Network Embedding 被引量:1
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作者 Hong Li Jianjun Li +2 位作者 Guohui Li Rong Gao Lingyu Yan 《Computers, Materials & Continua》 SCIE EI 2023年第4期1687-1709,共23页
ExpertRecommendation(ER)aims to identify domain experts with high expertise and willingness to provide answers to questions in Community Question Answering(CQA)web services.How to model questions and users in the hete... ExpertRecommendation(ER)aims to identify domain experts with high expertise and willingness to provide answers to questions in Community Question Answering(CQA)web services.How to model questions and users in the heterogeneous content network is critical to this task.Most traditional methods focus on modeling questions and users based on the textual content left in the community while ignoring the structural properties of heterogeneous CQA networks and always suffering from textual data sparsity issues.Recent approaches take advantage of structural proximities between nodes and attempt to fuse the textual content of nodes for modeling.However,they often fail to distinguish the nodes’personalized preferences and only consider the textual content of a part of the nodes in network embedding learning,while ignoring the semantic relevance of nodes.In this paper,we propose a novel framework that jointly considers the structural proximity relations and textual semantic relevance to model users and questions more comprehensively.Specifically,we learn topology-based embeddings through a hierarchical attentive network learning strategy,in which the proximity information and the personalized preference of nodes are encoded and preserved.Meanwhile,we utilize the node’s textual content and the text correlation between adjacent nodes to build the content-based embedding through a meta-context-aware skip-gram model.In addition,the user’s relative answer quality is incorporated to promote the ranking performance.Experimental results show that our proposed framework consistently and significantly outperforms the state-of-the-art baselines on three real-world datasets by taking the deep semantic understanding and structural feature learning together.The performance of the proposed work is analyzed in terms of MRR,P@K,and MAP and is proven to be more advanced than the existing methodologies. 展开更多
关键词 Heterogeneous network learning expert recommendation semantic representation community question answering
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ALBERT with Knowledge Graph Encoder Utilizing Semantic Similarity for Commonsense Question Answering 被引量:1
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作者 Byeongmin Choi YongHyun Lee +1 位作者 Yeunwoong Kyung Eunchan Kim 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期71-82,共12页
Recently,pre-trained language representation models such as bidirec-tional encoder representations from transformers(BERT)have been performing well in commonsense question answering(CSQA).However,there is a problem th... Recently,pre-trained language representation models such as bidirec-tional encoder representations from transformers(BERT)have been performing well in commonsense question answering(CSQA).However,there is a problem that the models do not directly use explicit information of knowledge sources existing outside.To augment this,additional methods such as knowledge-aware graph network(KagNet)and multi-hop graph relation network(MHGRN)have been proposed.In this study,we propose to use the latest pre-trained language model a lite bidirectional encoder representations from transformers(ALBERT)with knowledge graph information extraction technique.We also propose to applying the novel method,schema graph expansion to recent language models.Then,we analyze the effect of applying knowledge graph-based knowledge extraction techniques to recent pre-trained language models and confirm that schema graph expansion is effective in some extent.Furthermore,we show that our proposed model can achieve better performance than existing KagNet and MHGRN models in CommonsenseQA dataset. 展开更多
关键词 Commonsense reasoning question answering knowledge graph language representation model
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Factors Contributing to the Acceptability of Second Dose of Measles Vaccine among Children in Livingstone District, Zambia
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作者 Mirriam Nchimunya Dorothy Chanda Emmanuel Musenge 《Open Journal of Pediatrics》 CAS 2023年第2期220-234,共15页
Introduction: Measles is a viral disease that is a major public health problem in both developed and developing countries. It is a contagious disease resulting from infection with the measles virus and is still respon... Introduction: Measles is a viral disease that is a major public health problem in both developed and developing countries. It is a contagious disease resulting from infection with the measles virus and is still responsible for more than 100,000 deaths per year. Although vaccination is one of the most successful and cost-effective public health interventions to reduce mortality and morbidity, approximately 1.4 million children worldwide die from vaccine-preventable diseases each year. In Zambia, MCV2 was 66% below WHO recommended target of 95%. This study therefore assessed the acceptability of second dose measles vaccination services among caretakers/mothers with children less than two years of age in Livingstone, Zambia. Methods: The study used analytical cross-sectional study design. A logistic regression analysis was performed to identify factors associated with acceptability of the second dose of measles vaccine. A semi structured questionnaire was administered to collect data on socio demographic characteristics and factors related to acceptability of the second dose of measles vaccine. SPSS version 26.0 was used for descriptive and inferential analysis at 5% level of significance. Results: There was no statistically significant difference in acceptability of the second dose of measles vaccine by gender, marital status, type of employment, income level, socio-cultural and traditional beliefs, and education level. However, there was a statistically significant difference in acceptability of the second dose of measles vaccine by knowledge level of second dose of measles vaccine. A Chi square test result indicated that second dose acceptability was higher with less children than that of respondents with many children (χ2(5) = 15.3, p and knowledge levels (χ2(2) = 14.8, p Changes in knowledge level from medium to high reduced the odds of second dose measles vaccine acceptability. Furthermore, this study showed that acceptance of the second measles vaccination increased from mothers/caretakers with low knowledge (3.6%) to medium knowledge (13.3%) and finally high knowledge (83.1%). Conclusion: Tailored messaging to increase knowledge among mothers and caregivers on the importance of the second dose of measles vaccine is critical in improving acceptability. Therefore, the researchers recommend that the health providers should continue to raise awareness associated with the low acceptability of the second dose of measles vaccine and improve on child preventable diseases such as measles. 展开更多
关键词 MEASLES second Dose ACCEPTABILITY Caretakers
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