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Somewhere This Side of the View from Nowhere: On the Phenomenological Prepredicative Grounding of the Idea of Objectivity
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作者 Andrea Altobrando 《学术界》 CSSCI 北大核心 2019年第1期197-211,共15页
Although objectivity is mainly accounted for in terms of linguistic thought and communication,in this article I will aim to showthat at least one condition of possibility for our understanding of objectivity is ground... Although objectivity is mainly accounted for in terms of linguistic thought and communication,in this article I will aim to showthat at least one condition of possibility for our understanding of objectivity is grounded on a prepredicative,i. e. pre-linguistic and pre-communicative,level. I will endorse a Husserlian viewpoint on the issue,and I will try to develop some aspects of the Husserlian account of three-dimensional thing-perception by means of which I will showhowprepredicative experience can actually offer us a fundamental element of our common understanding of objectivity. In doing this,it will be necessary to acknowledge thing-perception as being primarily intertwined with indeterminacy. I will claim that only on the basis of such an intuitive and prepredicative access to the things as partially indeterminate,first,and as determinable,second,is it possible to have an understanding of the world as something (at least partially) independent from the intuition (s) all subjects can have of it. By means of the addition of a consciousness of the thing as accessible to other subjects,one achieves a vision of the thing as fully determinate in itself. This"vision",however,takes one to be aware of the determination of the thing as lying beyond any intuitive grasp of it. The result will,thus,be that the prepredicative constitution of our basic sense of objectivity leads us to intend the world as something which should be accounted for (also) by means of sources different from intuition. 展开更多
关键词 objectivity thing-perception prepredicative experience INDETERMINACY Husserlian EPISTEMOLOGY
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ON UNIQUENESS,EXISTENCE AND OBJECTIVITY OF S-R DECOMPOSITION THEOREM
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作者 陈勉 梁景伟 +1 位作者 陈熙 陈至达 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第9期817-823,共7页
For a physically possible deformation field of a continuum, the deformation gradient function F can be decomposed into direct sum of a symmetric tensor S and on orthogonal tensor R, which is called S-R decomposition t... For a physically possible deformation field of a continuum, the deformation gradient function F can be decomposed into direct sum of a symmetric tensor S and on orthogonal tensor R, which is called S-R decomposition theorem. In this paper, the S-R decomposition unique existence theorem is proved, by employing matrix and tensor method. Also, a brief proof of its objectivity is given. 展开更多
关键词 S-R decomposition theorem UNIQUENESS EXISTENCE objectivity
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Viewpoint Arrangement and Mental Space Configuration: A Cognitive Analysis on Objectivity Construction in Journalistic Narratives
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作者 LI Gui-dong 《Journal of Literature and Art Studies》 2019年第3期301-309,共9页
This paper presents an analysis on how objectivity is discursively constructed in journalistic narratives by drawing on the theories of viewpoint and mental space in Cognitive Linguistics. It is posited that at least ... This paper presents an analysis on how objectivity is discursively constructed in journalistic narratives by drawing on the theories of viewpoint and mental space in Cognitive Linguistics. It is posited that at least three mental spaces are projected by a narrative discourse, i.e., a narrated event space, a narrating space, and a basic space, and the distance between the first two spaces determines the degree of objectivity in the narrative discourse. A schema which represents the configuration of the different spaces is proposed and applied in the analysis of journalistic narratives to explore the strategies of objectivity construction. The analysis reveals that what the different journalistic narratives have in common in the construction of objectivity is to distance the narrated event space and the narrating space with the former being foregrounded in the viewpoint arrangement. 展开更多
关键词 VIEWPOINT MENTAL space objectivity journalistic NARRATIVE
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Subjectivity Versus Objectivity in Teaching Foreign Language
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作者 Miguel Neneve Lusinilda Carla Martins 《Cultural and Religious Studies》 2017年第3期134-141,共8页
In this paper we propose to discuss the issue of subjectivity versus objectivity teaching practice of foreign language, especially English, in Brazil. Starting from the short story "The Parrot and Descartes" by Paul... In this paper we propose to discuss the issue of subjectivity versus objectivity teaching practice of foreign language, especially English, in Brazil. Starting from the short story "The Parrot and Descartes" by Pauline Melville, we argue that Cartesianism has influenced a view on education which tends to consider good and valuable what is "scientific", "objective" and "universal". The subjective and the local seem to be considered undesirable and unreliable. Brazilian scholars on the education field, such as Coracini and Souza are important support for our argument. 展开更多
关键词 foreign language teaching subejctivity objectivity RATIONALISM
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Mechanization of Hearing in Chao Yuen Ren’s Dialect Research,1927-1936:Senses,Objectivity,and Observation
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作者 Chen-Pang Yeang 《Chinese Annals of History of Science and Technology》 2019年第2期94-117,共24页
When scientific research began in early twentieth-century China,a key issue was the acquisition of reliable empirical information through objective and precise observations.This article examines a specific case where ... When scientific research began in early twentieth-century China,a key issue was the acquisition of reliable empirical information through objective and precise observations.This article examines a specific case where a scientist grappled with such an issue:the linguist Chao Yuen Ren’s application of mechanical means in his phonetic studies.In the 1920s–1930s,Chao conducted a series of field and lab studies on the dialects in southern and central China.In contrast to traditional scholars’exclusive reliance on sharp ears and rhyme books,Chao employed mechanical devices to inscribe and analyze the spectrographs of dialectical tones and used phonographs to record the articulations of his subjects.It is demonstrated that Chao’s machines not only provided a new method of observation;they also altered the theoretical understanding of certain fundamental categories in Chinese phonology,such as tones.Moreover,Chao did not aim to replace human perception with automatic mechanisms in empirical investigations.Rather,the use of machines in his research called for an active and engaged scientific persona. 展开更多
关键词 mechanical objectivity PHONETICS TONE phonograph Chinese dialects
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Objectivity in the historiography of COVID-19 pandemic
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作者 Orhan Onder 《History & Philosophy of Medicine》 2022年第3期6-8,共3页
The world is facing a once-in-a-lifetime situation:the COVID-19 pandemic.During the pandemic,the World Health Organization announced an infodemic as well.This infodemic caused infollution and sparked many controversie... The world is facing a once-in-a-lifetime situation:the COVID-19 pandemic.During the pandemic,the World Health Organization announced an infodemic as well.This infodemic caused infollution and sparked many controversies.Pandemics as extraordinary occurrences are always attractive to historians.However,infodemics and biased information threaten objective history-writing.Objectivity as it regards historians is already a much-discussed subject.In this commentary,the fundamental theories about objectivity are delineated.Second,the relationship between the infodemic and COVID-19 pandemic is explained.Lastly,the problems regarding objectivity in the historiography of the COVID-19 pandemic are explored. 展开更多
关键词 COVID-19 PANDEMIC infodemic HISTORIOGRAPHY objectivity fake news
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On the Linguistic Aspects of Objectivity in English Journalism
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作者 Li Ganbin 《赣南师范学院学报》 1997年第2期90-95,共6页
OntheLinguisticAspectsofObjectivityinEnglishJournalism①LiGanbinAbstractObjectivityisaverycomplexandimportant... OntheLinguisticAspectsofObjectivityinEnglishJournalism①LiGanbinAbstractObjectivityisaverycomplexandimportantaspectinnewsrepor... 展开更多
关键词 LINGUISTIC objectivity JOURNALISM techniques INTRODUCTION
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The Objectivity of China English
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作者 谢芳 《海外英语》 2013年第20期248-249,共2页
China English, as one of the English varieties, is an objective reality. It is different from Chinglish which is an interlanguage for Chinese English learners. This paper expresses the definition of China English, its... China English, as one of the English varieties, is an objective reality. It is different from Chinglish which is an interlanguage for Chinese English learners. This paper expresses the definition of China English, its objectivity and manifestations in terms of pronunciation, vocabulary, syntax and text. 展开更多
关键词 China ENGLISH objectivity ACCEPTABILITY
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Subjectivities of the Scientific Endeavor:Noting the Illusion of Objectivity in the History of Science and Medicine
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作者 Imanni K.Sheppard 《History & Philosophy of Medicine》 2022年第1期4-8,共5页
The history of science and medicine has long been steeped in the notion that they are objective(untainted by the philosophical and ideological ebbs and flows of society)and utilitarian(doing what is best for the great... The history of science and medicine has long been steeped in the notion that they are objective(untainted by the philosophical and ideological ebbs and flows of society)and utilitarian(doing what is best for the greater good).Because of this,scientific and medical epistemologies and praxis are often held to an esteem that is unquestioned,celebrated,and occasionally unchecked.A closer look at the history of science and medicine,however,readily reveal the extent to which the milieu of society has informed scientific and medical endeavors.As such,an understanding of how the subjectivities of scientific and medical endeavors situate within our contemporary disciplines and practices is significant to one’s ability to truly understand said disciplines.Likewise,such an evaluation will provide insight into our role in perpetuating the illusion of objectivity in these fields.With this in mind,this paper provides a philosophical and historical examination of the concept of objectivity(in contrast to subjectivity)in science and medicine. 展开更多
关键词 objectivity SUBJECTIVITY history of science history of medicine natural law
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Canadian Agility and Movement Skill Assessment(CAMSA):Validity, objectivity, and reliability evidence for children 8–12 years of age 被引量:13
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作者 Patricia E.Longmuir Charles Boyer +6 位作者 Meghann Lloyd Michael M.Borghese Emily Knight Travis J.Saunders Elena Boiarskaia Weimo Zhu Mark S.Tremblay 《Journal of Sport and Health Science》 SCIE 2017年第2期231-240,共10页
Purpose: The primary aim of this study was to develop an assessment of the fundamental, combined, and complex movement skills required to support childhood physical literacy. The secondary aim was to establish the fea... Purpose: The primary aim of this study was to develop an assessment of the fundamental, combined, and complex movement skills required to support childhood physical literacy. The secondary aim was to establish the feasibility, objectivity, and reliability evidence for the assessment.Methods: An expert advisory group recommended a course format for the assessment that would require children to complete a series of dynamic movement skills. Criterion-referenced skill performance and completion time were the recommended forms of evaluation. Children, 8–12 years of age, self-reported their age and gender and then completed the study assessments while attending local schools or day camps. Face validity was previously established through a Delphi expert(n = 19, 21% female) review process. Convergent validity was evaluated by age and gender associations with assessment performance. Inter-and intra-rater(n = 53, 34% female) objectivity and test–retest(n = 60, 47% female) reliability were assessed through repeated test administration.Results: Median total score was 21 of 28 points(range 5–28). Median completion time was 17 s. Total scores were feasible for all 995 children who self-reported age and gender. Total score did not differ between inside and outside environments(95% confidence interval(CI) of difference:-0.7 to 0.6;p = 0.91) or with/without footwear(95%CI of difference:-2.5 to 1.9; p = 0.77). Older age(p < 0.001, η2= 0.15) and male gender(p < 0.001, η2= 0.02)were associated with a higher total score. Inter-rater objectivity evidence was excellent(intraclass correlation coefficient(ICC) = 0.99) for completion time and substantial for skill score(ICC = 0.69) for 104 attempts by 53 children(34% female). Intra-rater objectivity was moderate(ICC = 0.52) for skill score and excellent for completion time(ICC = 0.99). Reliability was excellent for completion time over a short(2–4 days; ICC = 0.84) or long(8–14days; ICC = 0.82) interval. Skill score reliability was moderate(ICC = 0.46) over a short interval, and substantial(ICC = 0.74) over a long interval.Conclusion: The Canadian Agility and Movement Skill Assessment is a feasible measure of selected fundamental, complex and combined movement skills, which are an important building block for childhood physical literacy. Moderate-to-excellent objectivity was demonstrated for children 8–12 years of age. Test–retest reliability has been established over an interval of at least 1 week. The time and skill scores can be accurately estimated by 1 trained examiner. 展开更多
关键词 Agility course CHILDREN Dynamic motor skill Locomotor skill Object manipulation Population assessment
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Automated Pipe Defect Identification in Underwater Robot Imagery with Deep Learning
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作者 Mansour Taheri Andani Farhad Ameri 《哈尔滨工程大学学报(英文版)》 2026年第1期197-215,共19页
Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challeng... Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challenge due to factors such as light scattering,absorption,restricted visibility,and ambient noise.The advancement of deep learning has introduced powerful techniques for processing large amounts of unstructured and imperfect data collected from underwater environments.This study evaluated the efficacy of the You Only Look Once(YOLO)algorithm,a real-time object detection and localization model based on convolutional neural networks,in identifying and classifying various types of pipeline defects in underwater settings.YOLOv8,the latest evolution in the YOLO family,integrates advanced capabilities,such as anchor-free detection,a cross-stage partial network backbone for efficient feature extraction,and a feature pyramid network+path aggregation network neck for robust multi-scale object detection,which make it particularly well-suited for complex underwater environments.Due to the lack of suitable open-access datasets for underwater pipeline defects,a custom dataset was captured using a remotely operated vehicle in a controlled environment.This application has the following assets available for use.Extensive experimentation demonstrated that YOLOv8 X-Large consistently outperformed other models in terms of pipe defect detection and classification and achieved a strong balance between precision and recall in identifying pipeline cracks,rust,corners,defective welds,flanges,tapes,and holes.This research establishes the baseline performance of YOLOv8 for underwater defect detection and showcases its potential to enhance the reliability and efficiency of pipeline inspection tasks in challenging underwater environments. 展开更多
关键词 YOLO8 Underwater robot Object detection Underwater pipelines Remotely operated vehicle Deep learning
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Is Objectivity Really an Objective Concept?
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作者 Nicolas Van Goethem 《Annals of Applied Mathematics》 2022年第4期441-492,共52页
Objectivity is the name given to covariance with respect to changes in observers by the action of the Euclidean group and is a central concept for mathematical modelling in Physics and Continuum mechanics.However,this... Objectivity is the name given to covariance with respect to changes in observers by the action of the Euclidean group and is a central concept for mathematical modelling in Physics and Continuum mechanics.However,this notion is delicate and therefore hard to understand by both mechanicians and mathematicians,precisely because it resides at the junction of the two disciplines and hence appeals to knowledge and notions from both fields to become clear.In a first part(“behind objectivity”)some classical notions of objectivity and frame-dependence are presented,discussed and critically revisited with the purpose to introduce in a second part(“beyond objectivity”)a novel modelling approach in incompatible elasticity,based on intrinsic and geometric concepts,related but distinct from conventional objectivity.This contribution is primarily conceived to assist students,academics and researchers,mathematicians in particular,to find their way through some difficult and often ill-understood concepts of Physics and Continuum mechanics,since objectivity still remains nowadays a profound concept that deserves our attention. 展开更多
关键词 Frame indifference objectivity ELASTICITY INCOMPATIBILITY
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Geiger's Critique of Dilettantism:Towards Objectivity in Aesthetic Perception
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作者 LAN Ying 《清华西方哲学研究》 2024年第1期259-282,共24页
Geiger considers dilettantism as an aesthetic attitude(inner concentration)that undermines the subject's ability to truly perceive the essential value of the artwork and thus calls for outer concentration to actua... Geiger considers dilettantism as an aesthetic attitude(inner concentration)that undermines the subject's ability to truly perceive the essential value of the artwork and thus calls for outer concentration to actualize the justice of the work itself.Geiger's position suggests that we must pay equitable attention to artworks and that this attitude requires a theory of aesthetic perception—phenomenological realism.However,the complexity of the aesthetic experience presents Geiger with several challenges,not least of which is the realisation of an attitude that bridges emotion and value in aesthetic experience.This paper will attempt to defend and develop the legitimacy of Geiger's position.First,I will clarify Geiger's critique of dilettantism and suggest how this critique distinguishes him from other aesthetic claims;second,I argue that Geiger argues for an aesthetic attitude that distinguishes everyday emotions and thus ensures the value of the work of art as its own;finally,I will complete Geiger's position by drawing on later phenomenology that answers the question of how we realise the perception of artworks. 展开更多
关键词 Dilettantism EMOTION Aesthetic Value PERCEPTION objectivity
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ON THE OBJECTIVITY OF THE IELTS TEST
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作者 Chen Weidong Sino-British Predeparture Project Preparatory Department Beijing Language Institute 《Chinese Journal of Applied Linguistics》 1996年第2期84-86,共3页
IntroductionEvery.year many Chinese scientists,scholars,university teachers,doctors,and other professional go toBritain to do research or continue their education sponsored by various bodies such as the SBFSS(Sino-Bri... IntroductionEvery.year many Chinese scientists,scholars,university teachers,doctors,and other professional go toBritain to do research or continue their education sponsored by various bodies such as the SBFSS(Sino-British Friendship Scholarship Scheme)of the TC(Technical Cooperation)scholarship holders:Most of these people are aged between 30 and 50.They have all passed a screening test called the EPT(theEnglish Proficiency Test)before being nominated as candidates.Most attend one or two sessions of apredeparture training course in one of the three pre-departure training centres in China-Beijing,Shanghai and Chengdu.The purpose of these courses includes improving the candidates’languageskills,preparing them with some study skills for their research/study in Britain,giving them knowledgeand advice about living an studying in Britain,and practice for the IELTS test.Each session of thetraining is 4-5 months long.At the end of the training the candidates are given the IELTS test.Thosewho fail to reach Band 6 have to attend one more session and take the test again. 展开更多
关键词 IELTS TEST 英语水平考试 ON THE objectivity OF THE IELTS TEST
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Rising frequency of ozone-favorable synoptic weather patterns contributes to 2015-2022 ozone increase in Guangzhou 被引量:2
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作者 Nanxi Liu Guowen He +8 位作者 Haolin Wang Cheng He Haofan Wang Chenxi Liu Yiming Wang Haichao Wang Lei Li Xiao Lu Shaojia Fan 《Journal of Environmental Sciences》 2025年第2期502-514,共13页
Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examine... Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examined.In this study,we apply two widely-used objective methods,the self-organizing map(SOM)and K-means clustering analysis,to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022.We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities.In the case of classifying six SWPs,the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods,and the difference in themean frequency of each SWP is less than 7%.The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature,lower cloud cover,relative humidity,and wind speed,and stronger subsidence compared to climatology mean.We find that during 2015-2022,the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 days/year,faster than the increases in the ozone exceedance days(3.0 days/year).The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6.In particular,the significant increase in ozone-favorable SWPs in 2022,especially the Subtropical High type which typically occurs in September,is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022.Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou. 展开更多
关键词 Ozone(O_(3)) Objective weather classification methods Synoptic weather patterns Trends GUANGZHOU
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Hybrid receptive field network for small object detection on drone view 被引量:1
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作者 Zhaodong CHEN Hongbing JI +2 位作者 Yongquan ZHANG Wenke LIU Zhigang ZHU 《Chinese Journal of Aeronautics》 2025年第2期322-338,共17页
Drone-based small object detection is of great significance in practical applications such as military actions, disaster rescue, transportation, etc. However, the severe scale differences in objects captured by drones... Drone-based small object detection is of great significance in practical applications such as military actions, disaster rescue, transportation, etc. However, the severe scale differences in objects captured by drones and lack of detail information for small-scale objects make drone-based small object detection a formidable challenge. To address these issues, we first develop a mathematical model to explore how changing receptive fields impacts the polynomial fitting results. Subsequently, based on the obtained conclusions, we propose a simple but effective Hybrid Receptive Field Network (HRFNet), whose modules include Hybrid Feature Augmentation (HFA), Hybrid Feature Pyramid (HFP) and Dual Scale Head (DSH). Specifically, HFA employs parallel dilated convolution kernels of different sizes to extend shallow features with different receptive fields, committed to improving the multi-scale adaptability of the network;HFP enhances the perception of small objects by capturing contextual information across layers, while DSH reconstructs the original prediction head utilizing a set of high-resolution features and ultrahigh-resolution features. In addition, in order to train HRFNet, the corresponding dual-scale loss function is designed. Finally, comprehensive evaluation results on public benchmarks such as VisDrone-DET and TinyPerson demonstrate the robustness of the proposed method. Most impressively, the proposed HRFNet achieves a mAP of 51.0 on VisDrone-DET with 29.3 M parameters, which outperforms the extant state-of-the-art detectors. HRFNet also performs excellently in complex scenarios captured by drones, achieving the best performance on the CS-Drone dataset we built. 展开更多
关键词 Drone remote sensing Object detection on drone view Small object detector Hybrid receptive field Feature pyramid network Feature augmentation Multi-scale object detection
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A Systematic Review of Deep Learning-Based Object Detection in Agriculture: Methods, Challenges, and Future Directions 被引量:1
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作者 Mukesh Dalal Payal Mittal 《Computers, Materials & Continua》 2025年第7期57-91,共35页
Deep learning-based object detection has revolutionized various fields,including agriculture.This paper presents a systematic review based on the PRISMA 2020 approach for object detection techniques in agriculture by ... Deep learning-based object detection has revolutionized various fields,including agriculture.This paper presents a systematic review based on the PRISMA 2020 approach for object detection techniques in agriculture by exploring the evolution of different methods and applications over the past three years,highlighting the shift from conventional computer vision to deep learning-based methodologies owing to their enhanced efficacy in real time.The review emphasizes the integration of advanced models,such as You Only Look Once(YOLO)v9,v10,EfficientDet,Transformer-based models,and hybrid frameworks that improve the precision,accuracy,and scalability for crop monitoring and disease detection.The review also highlights benchmark datasets and evaluation metrics.It addresses limitations,like domain adaptation challenges,dataset heterogeneity,and occlusion,while offering insights into prospective research avenues,such as multimodal learning,explainable AI,and federated learning.Furthermore,the main aim of this paper is to serve as a thorough resource guide for scientists,researchers,and stakeholders for implementing deep learning-based object detection methods for the development of intelligent,robust,and sustainable agricultural systems. 展开更多
关键词 Artificial intelligence object detection computer vision AGRICULTURE deep learning
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Impacts of synoptic weather patterns on Hefei's ozone in warm season and analysis of transport pathways during extreme pollution events 被引量:1
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作者 Feng Hu Pinhua Xie +5 位作者 Jin Xu Ang Li Yinsheng Lv Zhidong Zhang Jiangyi Zheng Xin Tian 《Journal of Environmental Sciences》 2025年第10期371-384,共14页
Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and... Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and source contributions to historical EOPEs is still lacking.In this paper,the K-means clustering method is applied to identify six dominant SWPs during the warm season in the Yangtze River Delta(YRD)region from 2016 to 2022.It provides an integrated analysis of the meteorological factors affecting ozone pollution in Hefei under different SWPs.Using the WRF-FLEXPART model,the transport pathways(TPPs)and geographical sources of the near-surface air masses in Hefei during EOPEs are investigated.The results reveal that Hefei experienced the highest ozone concentration(134.77±42.82μg/m^(3)),exceedance frequency(46 days(23.23%)),and proportion of EOPEs(21 instances,47.7%)under the control of peripheral subsidence of typhoon(Type 5).Regional southeast winds correlated with the ozone pollution in Hefei.During EOPEs,a high boundary layer height,solar radiation,and temperature;lowhumidity and cloud cover;and pronounced subsidence airflow occurred over Hefei and the broader YRD region.The East-South(E_S)patterns exhibited the highest frequency(28 instances,65.11%).Regarding the TPPs and geographical sources of the near-surface air masses during historical EOPEs.The YRD was the main source for land-originating air masses under E_S patterns(50.28%),with Hefei,southern Anhui,southern Jiangsu,and northern Zhejiang being key contributors.These findings can help improve ozone pollution early warning and control mechanisms at urban and regional scales. 展开更多
关键词 OZONE Objective weather classification Transport pathway Source attribution Hefei
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Multi-objective optimization of grinding process parameters for improving gear machining precision 被引量:1
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作者 YOU Tong-fei HAN Jiang +4 位作者 TIAN Xiao-qing TANG Jian-ping LU Yi-guo LI Guang-hui XIA Lian 《Journal of Central South University》 2025年第2期538-551,共14页
The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can caus... The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can cause changes in cutting force/heat,resulting in affecting gear machining precision.Therefore,this paper studies the effect of different process parameters on gear machining precision.A multi-objective optimization model is established for the relationship between process parameters and tooth surface deviations,tooth profile deviations,and tooth lead deviations through the cutting speed,feed rate,and cutting depth of the worm wheel gear grinding machine.The response surface method(RSM)is used for experimental design,and the corresponding experimental results and optimal process parameters are obtained.Subsequently,gray relational analysis-principal component analysis(GRA-PCA),particle swarm optimization(PSO),and genetic algorithm-particle swarm optimization(GA-PSO)methods are used to analyze the experimental results and obtain different optimal process parameters.The results show that optimal process parameters obtained by the GRA-PCA,PSO,and GA-PSO methods improve the gear machining precision.Moreover,the gear machining precision obtained by GA-PSO is superior to other methods. 展开更多
关键词 worm wheel gear grinding machine gear machining precision machining process parameters multi objective optimization
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