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How Investor Sentiment Influences Stock Price Informativeness of Firms’Future Earnings:Evidence From China’s Stock Market
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作者 Junfeng Wang 《Journal of Sustainable Business and Economics》 2024年第4期1-32,共32页
This paper explores whether the level of stock price informativeness about listed companies’future earnings is influenced by investor sentiment.In prior studies,investor sentiment,which can be regarded as the mood of... This paper explores whether the level of stock price informativeness about listed companies’future earnings is influenced by investor sentiment.In prior studies,investor sentiment,which can be regarded as the mood of the market,is defined as a belief about unjustified firms’future cash flow,investment returns and risks in capital markets.At the same time,stock price informativeness indicates how much information about a firm’s future earnings is reflected by stock prices.Higher price informativeness indicates a higher market efficiency level.Using linear regression analysis based on panel data from China’s stock market and listed companies,this research documents how stock price informativeness can be reduced by investor sentiment during market pessimism.However,although the explanatory power of future earnings over stock returns is strengthened by positive sentiment,it is not certain that positive sentiment increases price informativeness since the asset price bubble exists with extreme market optimism.Furthermore,the effect of sentiment on price informativeness would be weakened by higher state-owned shareholding.These empirical results imply that sentiment,to a certain degree,causes the investors’ignorance during pessimism and exaggeration during optimism over firms’earning prospects.Moreover,investors usually lack favour for state-owned enterprises during optimism,even though these companies actually have considerable earning prospects.While during pessimism,which usually happens after a crisis,the profitability and reliability of these state-owned enterprises are again emphasised by investors. 展开更多
关键词 SENTIMENT informativeNESS Stock market efficiency State-owned shareholding
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ML and DL-based Phishing Website Detection:The Effects of Varied Size Datasets and Informative Feature Selection Techniques
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作者 Kibreab Adane Berhanu Beyene Mohammed Abebe 《Journal of Artificial Intelligence and Technology》 2024年第1期18-30,共13页
Onemust interact with a specific webpage or website in order to use the Internet for communication,teamwork,and other productive activities.However,because phishing websites look benign and not all website visitors ha... Onemust interact with a specific webpage or website in order to use the Internet for communication,teamwork,and other productive activities.However,because phishing websites look benign and not all website visitors have the same knowledge and skills to inspect the trustworthiness of visited websites,they are tricked into disclosing sensitive information and making them vulnerable to malicious software attacks like ransomware.It is impossible to stop attackers fromcreating phishingwebsites,which is one of the core challenges in combating them.However,this threat can be alleviated by detecting a specific website as phishing and alerting online users to take the necessary precautions before handing over sensitive information.In this study,five machine learning(ML)and DL algorithms—cat-boost(CATB),gradient boost(GB),random forest(RF),multilayer perceptron(MLP),and deep neural network(DNN)—were tested with three different reputable datasets and two useful feature selection techniques,to assess the scalability and consistency of each classifier’s performance on varied dataset sizes.The experimental findings reveal that the CATB classifier achieved the best accuracy across all datasets(DS-1,DS-2,and DS-3)with respective values of 97.9%,95.73%,and 98.83%.The GB classifier achieved the second-best accuracy across all datasets(DS-1,DS-2,and DS-3)with respective values of 97.16%,95.18%,and 98.58%.MLP achieved the best computational time across all datasets(DS-1,DS-2,and DS-3)with respective values of 2,7,and 3 seconds despite scoring the lowest accuracy across all datasets. 展开更多
关键词 ANOVA-F-test deep learning feature selection technique machine learning mutual information phishing website datasets phishing website detection
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Public Speaking的技巧与策略(8)——如何进行Informative Presentation
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作者 杨俊峰 《英语知识》 2000年第10期32-34,共3页
演讲和面对面谈话非常相似。如果我们想教授某一种技能,如演示性演讲,我们必须首先让听众知道我们想让他们了解什么,做什么。如果是劝说式演讲或辩论,我们必须在劝服听众相信我们的观点前使他们了解所要讨论的题目。这种告知听众的做法... 演讲和面对面谈话非常相似。如果我们想教授某一种技能,如演示性演讲,我们必须首先让听众知道我们想让他们了解什么,做什么。如果是劝说式演讲或辩论,我们必须在劝服听众相信我们的观点前使他们了解所要讨论的题目。这种告知听众的做法要求我们清晰简洁地提出我们的主题,然后用具体的细节、例证来支持主题或在辩论中提出具体明确的参考材料。 展开更多
关键词 informative Presentation Public Speaking 优质奶牛 声像资料
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Old nest material functions as an informative cue in making nest-site selection decisions in the European Kestrel(Falco tinnunculus) 被引量:1
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作者 Mingju E Tuo Wang +5 位作者 Shangyu Wang Ye Gong Jiangping Yu Lin Wang Wei Ou Haitao Wang 《Avian Research》 CSCD 2019年第4期423-430,共8页
Background:For secondary cavity-nesting bird species that do not add lining materials to nests,the presence of old nest material or organic remains that have accumulated within nest cavities from previous breeding eve... Background:For secondary cavity-nesting bird species that do not add lining materials to nests,the presence of old nest material or organic remains that have accumulated within nest cavities from previous breeding events may be a cue of nest-site quality.These materials potentially contain information about past breeding success in con-and heterospecifics and may improve the thermal insulation of eggs during incubation.However,few studies have addressed whether the presence of old nest materials serves as a cue for cavity-nesting raptors when choosing specific nest sites.Methods:We conducted a 9-year nest box experiment to test whether old nest materials from con-and heterospecifics serve as informative cues to the European Kestrel(Falco tinnunculus)when making nest selection decisions,as this species uses nest boxes without adding nesting material.Results:The presence of old nest materials and entrance size best discriminated nest boxes occupied by European Kestrels from unoccupied boxes.Nest boxes containing conspecific organic remains,artificial dry leaf and branch material,and material left behind by Great Tits(Parus major)were reused at higher rates,especially those containing conspecific nest material,than nest boxes containing true or simulated nest materials from predators.In 2010,no single nest box was occupied by the same banded individual that occupied the box in the previous year(10 females and 2 males were banded in 2009).Conclusions:European Kestrels preferred nest boxes containing old nest material over empty boxes,which is consistent with previous findings that they exploit con-and heterospecific cues when deciding where to settle and breed,as old nest or organic material provides substrate for incubating females.Kestrels may be able to assess the predation risks associated with a specific nest site based on experience or the presence of prey remains.The repeated use of nest boxes across breeding seasons by kestrels cannot be entirely ascribed to philopatry.This study provides evidence that old nest materials are potentially used as informative cues when making nest-site selection decisions in European Kestrels. 展开更多
关键词 European Kestrel informative cue Nest box Nest materials
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The Fourier Notation of the Geomagnetic Signals Informative Parameters 被引量:1
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作者 Osvaldo Faggioni 《Journal of Signal and Information Processing》 2018年第3期153-166,共14页
The paper discusses the quantitative definition of the s/n (signal to noise ratio) by means of new computational parameters derived (and computed) by the Fourier analysis. The theme is of great relevance when the geom... The paper discusses the quantitative definition of the s/n (signal to noise ratio) by means of new computational parameters derived (and computed) by the Fourier analysis. The theme is of great relevance when the geomagnetic observed field has high transient noise and high energy content (i.e.geomagnetic signal interfered by human activity magnetic band) and when the signal analysis action is oriented to the detection of magnetic sources characterized by quasi-punctiform size, low energy level and kinetic mechanical status (i.e.uw armed terrorist). The paper shows the results obtained introducing two new informative spectral parameters: the informative capability “C” and the enhanced informative capability “eC”. These parameters are depending on the comparison of the energy of the target signal with total field energy and they are characteristics of each elementary signal. C classifies the energy of the spectrum in two metrological bands: elementary signal informative energy EI (band or single signal) and passive energy EP. This metrological classification of the energy overtakes the concept of noise: each signal is part of the noise band when it is not under observation and becomes out of the band when it is under observation (numerical observation→computation). C (and eC) allows to compute the value of the “visibility” of the informative signals in a high energy geomagnetic field (or spectrum). C is a fundamental parameter for the evaluation of the effectiveness of singularity magnetic metrology in the passive detection of small magnetic sources in high noised magnetic field. 展开更多
关键词 Geomatic informative Signal ANALYSIS FOURIER ANALYSIS GEOMAGNETISM Metrology of Singularity Frequency Domain Observations S/N Manipulation
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Informative Property of the Data Set in a Single-input Single-output (SISO) Closed-loop System with a Switching Controller
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作者 张聪 杨帆 叶昊 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1128-1135,共8页
Closed-loop identification is important and necessary to various model-based advanced process control strategies, whose performance depends greatly on the informative property of the data set. Switching control is an ... Closed-loop identification is important and necessary to various model-based advanced process control strategies, whose performance depends greatly on the informative property of the data set. Switching control is an important method in process control. Therefore, this paper studies the informative property of a data set in a single-input single-output (SISO) closed-loop system with a switching controller. It is proved that this data set is informative if the controller switches among at least two modes (i.e., feedback laws). Our result does not require any assumption on the way of switch and removes the constraints on the switching manner required in some classical literature. Finally, simulation case studies based on a continuous stirred-tank reactor (CSTR) process are given to validate the results. 展开更多
关键词 closed-loop system switching controller informative property continuous stirred-tank reactor process
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Using Informative Score for Instance Selection Strategy in Semi-Supervised Sentiment Classification
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作者 Vivian Lee Lay Shan Gan Keng Hoon +1 位作者 Tan Tien Ping Rosni Abdullah 《Computers, Materials & Continua》 SCIE EI 2023年第3期4801-4818,共18页
Sentiment classification is a useful tool to classify reviews about sentiments and attitudes towards a product or service.Existing studies heavily rely on sentiment classification methods that require fully annotated ... Sentiment classification is a useful tool to classify reviews about sentiments and attitudes towards a product or service.Existing studies heavily rely on sentiment classification methods that require fully annotated inputs.However,there is limited labelled text available,making the acquirement process of the fully annotated input costly and labour-intensive.Lately,semi-supervised methods emerge as they require only partially labelled input but perform comparably to supervised methods.Nevertheless,some works reported that the performance of the semi-supervised model degraded after adding unlabelled instances into training.Literature also shows that not all unlabelled instances are equally useful;thus identifying the informative unlabelled instances is beneficial in training a semi-supervised model.To achieve this,an informative score is proposed and incorporated into semisupervised sentiment classification.The evaluation is performed on a semisupervised method without an informative score and with an informative score.By using the informative score in the instance selection strategy to identify informative unlabelled instances,semi-supervised models perform better compared to models that do not incorporate informative scores into their training.Although the performance of semi-supervised models incorporated with an informative score is not able to surpass the supervised models,the results are still found promising as the differences in performance are subtle with a small difference of 2%to 5%,but the number of labelled instances used is greatly reduced from100%to 40%.The best finding of the proposed instance selection strategy is achieved when incorporating an informative score with a baseline confidence score at a 0.5:0.5 ratio using only 40%labelled data. 展开更多
关键词 Document-level sentiment classification semi-supervised learning instance selection informative score
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Semiparametric Estimator of Mean Conditional Residual Life Function under Informative Random Censoring from Both Sides
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作者 A. A. Abdushukurov F. A. Abdikalikov 《Applied Mathematics》 2015年第2期319-325,共7页
In this paper we study estimator of mean residual life function in fixed design regression model when life times are subjected to informative random censoring from both sides. We prove an asymptotic normality of estim... In this paper we study estimator of mean residual life function in fixed design regression model when life times are subjected to informative random censoring from both sides. We prove an asymptotic normality of estimators. 展开更多
关键词 informative CENSORING Power ESTIMATOR Regression Mean Residual LIFETIME
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Quality Requirements for Multimedia Interactive Informative Systems
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作者 Sylviane Levy Fernando Gamboa 《Journal of Software Engineering and Applications》 2013年第8期416-425,共10页
Multimedia Interactive Informative Systems (MIIS) are software applications resulting from the convergence of multiples technologies such as audiovisual, computing and communication. They aim to transmit information t... Multimedia Interactive Informative Systems (MIIS) are software applications resulting from the convergence of multiples technologies such as audiovisual, computing and communication. They aim to transmit information to a large, diverse and dispersed public. As with other mass media, the fulfillment of MIIS goals depends largely on the quality of communication between the system and end users. Therefore, those systems should be developed in order to ensure that this quality requirement is satisfied. If MIIS are constructed according to usual software engineering practices, the analysis discipline of the development process includes requirements identification and specification;however, these techniques are focused on functional requirements, and they do not give much importance to non-functional requirements. In this paper, we propose a development process based on the production of videogames which has two different phases: preproduction and production. The first phase, corresponding to requirements identification, derives into the concept of system. In order to translate this concept into a specification, we propose the use of new communicational attributes and a MIIS metamodel. The establishment of MIIS non-functional specification is the result of analyzing class diagrams through quality attributes. In order to evaluate if the specifications are responding to communicational attributes, a functional prototype is built and evaluated with end users. The proposed methodology is applied to a real case study. 展开更多
关键词 MULTIMEDIA INTERACTIVE informative SYSTEMS MULTIMEDIA QUALITY Model in Use QUALITY Requirements METAMODELING
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On the Informative Function of Language in the Poems and Couplets in Benzhu Temples in Dali,Yunnan
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作者 姚舒阳 《海外英语》 2020年第4期93-94,共2页
In Dali Bai Autonomous Prefecture,Yunnan Province,there exists a quite special and interesting cultural phenomenon of the Bai ethnic group,which is the belief in Benzhu.There are a lot of poems and couplets in Benzhu ... In Dali Bai Autonomous Prefecture,Yunnan Province,there exists a quite special and interesting cultural phenomenon of the Bai ethnic group,which is the belief in Benzhu.There are a lot of poems and couplets in Benzhu temples.The poems are carved on the walls and tablets.The couplets,being on both sides of the doors,are carved on planks or written on red paper.Lan guage used in the poems and couplets plays the informative function. 展开更多
关键词 LANGUAGE FUNCTION informative FUNCTION Bai ethnic group Benzhu POEMS COUPLETS
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Intertextile Beijing Features More Informative programme of seminars and trend forums add value to fair
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《China Textile》 2009年第3期18-18,共1页
Intertextile Beijing Apparel Fabrics,will be held from 29-31 March 2009 at the China International Exhibition Centre,will showcase the latest textiles from around the world on 48,000 sqm of exhibition space.The event ... Intertextile Beijing Apparel Fabrics,will be held from 29-31 March 2009 at the China International Exhibition Centre,will showcase the latest textiles from around the world on 48,000 sqm of exhibition space.The event has confirmed 1100 exhibitors from 14 countries and regions including 展开更多
关键词 Intertextile Beijing Features More informative programme of seminars and trend forums add value to fair
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Weighted-averaging-based classification of laser-induced breakdown spectroscopy measurements using most informative spectral lines
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作者 Ekta SRIVASTAVA Hyemin JANG +3 位作者 Sungho SHIN Janghee CHOI Sungho JEONG Euiseok HWANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第1期58-73,共16页
In this study,efficient spectral line selection and wcightcd-avcraging-bascd processing schemes are proposed for the classification of laser-induced breakdown spectroscopy(UBS)measurements.For fast on-line classificat... In this study,efficient spectral line selection and wcightcd-avcraging-bascd processing schemes are proposed for the classification of laser-induced breakdown spectroscopy(UBS)measurements.For fast on-line classification,a set of representative spectral lines arc selected ami processed relying on the information metric,instead of the time consuming full spectrum based analysis.I he most informative spectral line sets arc investigated by the joint mutual information estimation(MIR)evaluated with the Gaussian kernel density,where dominant intensity peaks associated with the concentrated components arc not necessarily most valuable for classification.In order to further distinguish the characteristic patterns of die LIBS measured spectrum,two-dimensional spectral images are synthesized through column-wise concatenation of the peaks along with their neighbors.For fast classification while preserv ing die effect of distinctive peak patterns,column-wise Gaussian weighted averaging is applied to die synthesized images,yielding a favorable trade off between classification performance and computational complexity.To explore the applicability of the proposed schemes,two applications of alloy classification and skin cancer detection arc investigated with the multi-class and binary support vector machines classifiers,respectively.Ihc MIE measures associated with selected spectral lines in bodi applications show a strong correlation to the actual classification or detection accuracy,which enables to find out meaningful combinations of spectral lines.In addition,the peak patterns of the selected lines and their Gaussian weighted averaging with nciehbors of the selected peaks efficiently distineuish different classes of LIBS measured spectrum. 展开更多
关键词 laser-induced breakdown spectroscopy mutual information weighted averaging alloy classification skin cancer detection
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Research of Impact of Geografical Latitute and Residual Ionospheric Noises on Informativeness of Measuring of Zenith Wet Delay of GPS Signals
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作者 A. Sh. Mehdiyev R. A. Eminov +1 位作者 N. Y. Ismayilov H. H. Asadov 《Positioning》 2015年第3期44-48,共5页
It is noted that necessity of further increase of accuracy of GPS positioning systems requires de-velopment of more perfect methods to compensate information losses occurred due to residual ionospheric delay by using ... It is noted that necessity of further increase of accuracy of GPS positioning systems requires de-velopment of more perfect methods to compensate information losses occurred due to residual ionospheric delay by using optimization procedures. According to the conditions of formulated optimization task, the signal/noise ratio in measurements of zenith wet delay depends on the second order ionospheric errors, geographic latitude and day of year. At the same time if we assume that the number of measurements at the fixed geographic site is proportional to geographic latitude and if we accept existence of only two antiphase scenarios for variation of residual ionospheric delay on latitude normed by their specific constant, there should be optimum functional dependence of precipitated water on latitude upon which the quantity of measuring information reaches the maximum. The mathematical grounding of solution of formulated optimization task is given. 展开更多
关键词 Zenith Wet Delay Information Optimization GPS Measurements IONOSPHERE GEOGRAPHIC LATITUDE
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Genomic Diversity in Three Populations of West Bengal,India,Using 15 Autosomal Forensically Informative STR Markers
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作者 Shreya Saha Soma Roy 《Journal of Forensic Science and Medicine》 2025年第2期131-138,共8页
Aims and Objectives:The plan of study was the evaluation of genetic diversity in the tribal populations of Northern West Bengal,tribal populations of southern West Bengal and the Muslim population of West Bengal,India... Aims and Objectives:The plan of study was the evaluation of genetic diversity in the tribal populations of Northern West Bengal,tribal populations of southern West Bengal and the Muslim population of West Bengal,India,using 15 autosomal STR markers.Further investigation was done to find out the genetic relatedness of the studied populations with other previously documented Indian populations.Result:The studied tribal population of Northern West Bengal and Southern West Bengal showed a wide range of observed heterozygosity values,viz,from 0.667 to 0.878 and 0.699 to 0.863 respectively.Same was the case with the tribal population of Southern Bengal where the observed heterozygosity values ranged between 0.699 to 0.863.For the Muslim population the observed heterozygosity value was in the range of 0.742 to 0.885.The combined value of non-exclusion probability for all the studied loci was 0.00000550 for the tribal population of Northern West Bengal,0.00004445 for the Muslim population of West Bengal and 0.00000806 for the tribal population of Southern West Bengal.The neighbor joining(NJ)tree and principal component analysis(PCA)resulted in the clustering of our studied populations with other previously studied Indian populations.Conclusion:The data thus obtained demonstrated high forensic efficacy and will be therefore helpful in several population genetics studies and forensic applications. 展开更多
关键词 Combined nonexclusion probability observed heterozygosity polymorphic information content short tandem repeats West Bengal
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Employee Stock Ownership Plans and Stock-price Informativeness 被引量:1
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作者 Yuehua Zuo Xin Huang +1 位作者 Xiaojun Liu Yunhao Dai 《China & World Economy》 2024年第3期162-190,共29页
This study examines the impact of employee stock ownership plans(ESOPs)on stock-price informativeness in Chinese stock markets.Its findings indicate that firms implementing ESOPs experienced an average 11.89 percent i... This study examines the impact of employee stock ownership plans(ESOPs)on stock-price informativeness in Chinese stock markets.Its findings indicate that firms implementing ESOPs experienced an average 11.89 percent increase in stock-price informativeness.The plans improved stock-price informativeness through increased external attention and supervision.An event study shows that ESOPs gave rise to an announcement effect,driven by anticipated performance improvements and the novelty associated with ESOPs.A mechanism analysis demonstrates that the implementation of ESOPs attracted market attention,and the increased market supervision resulting from this mitigated the moral hazards of management associated with ESOPs.Plans with more positive signals exerted a greater influence.Notably,ESOPs that prioritized management incentives gained more recognition in the market.As the incentive effects of ESOPs were weaker than those of equity incentive plans and the ESOPs lost novelty over time,the annual announcement effect diminished gradually.These findings underscore the necessity of strengthening ESOP incentives for continued optimization of priceefficiency. 展开更多
关键词 announcement effect corporate governance employee stock ownership plan stock-price informativeness
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BIM技术赋能在役桥梁安全与高效运维 被引量:2
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作者 张丽萍 王广 +2 位作者 王力 陈云峰 李子奇 《中国安全生产科学技术》 北大核心 2025年第1期101-108,共8页
为了保证运维阶段桥梁结构安全,提升桥梁运维工作的效率,开展公路混凝土梁式桥运维阶段建筑信息模型(building information modeling,BIM)技术应用研究。在对公路桥梁现行编码体系进行扩展的基础上,提出1种参数化快速建模方法,以快速完... 为了保证运维阶段桥梁结构安全,提升桥梁运维工作的效率,开展公路混凝土梁式桥运维阶段建筑信息模型(building information modeling,BIM)技术应用研究。在对公路桥梁现行编码体系进行扩展的基础上,提出1种参数化快速建模方法,以快速完成桥梁构件族的创建与整体模型的集成。借助Autodesk Revit软件应用程序编程接口(application programming interface,API),采用C#语言,开发公路混凝土梁式桥智慧运维状态评估系统,以实际工程应用进行验证分析。研究结果表明:全面统一的桥梁信息编码体系,能够提高桥梁信息统计与检索效率;提出的快速建模方法能够显著减少建模工作量,建模时间较传统建模方法可减少60%,并保证模型的准确性与规范性;运维状态评估系统能够实现养护数据的充分利用与桥梁评定工作的自动化,通过对桥梁运维信息的有效组织,实现服役性能的长期追踪,从而确保运营期桥梁结构状态安全稳定。研究结果可为公路混凝土梁式桥运维管理提供技术支撑,提升桥梁运维的数字化水平。 展开更多
关键词 桥梁工程 运维状态评估系统 Building Information Modeling 公路混凝土梁式桥
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改进Informed RRT^(*)算法移动机器人路径规划 被引量:2
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作者 鲁宇明 周羽逵 +2 位作者 郭鑫 池吕庭 戴骏 《计算机工程与应用》 北大核心 2025年第8期283-293,共11页
Informed RRT^(*)算法对初始解不敏感,规划出的路径太接近障碍物,导致路径不平滑。提出一种改进的Informed RRT^(*)路径规划算法,该算法改进了约束采样空间和引导策略。在采样初期,将采样区域限制在一个圆形区域,加快初始解收敛,在算法... Informed RRT^(*)算法对初始解不敏感,规划出的路径太接近障碍物,导致路径不平滑。提出一种改进的Informed RRT^(*)路径规划算法,该算法改进了约束采样空间和引导策略。在采样初期,将采样区域限制在一个圆形区域,加快初始解收敛,在算法规划的过程中引入人工势场中引力场和斥力场的思想,使机器人与障碍物保持安全距离,并向目标位置行进。对Informed RRT^(*)算法和基于目标偏置的Informed RRT^(*)算法(Goal-bias-Informed RRT^(*))以及改进后的Informed RRT^(*)算法进行比较实验,实验结果验证了改进后Informed RRT^(*)算法的有效性和优越性及稳定性。该算法较Informed RRT^(*)算法和Goal-bias-Informed RRT^(*)效率更高、更容易得到初始解、更安全、更平滑、更稳定。 展开更多
关键词 移动机器人 路径规划 随机采样 Informed RRT^(*)算法 目标偏置 约束采样空间
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基于多任务Informer模型的船舶轨迹预测及行为识别研究
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作者 李世刚 刘克中 +3 位作者 陈立家 周乃祺 周阳 黄嘉韬 《中国航海》 北大核心 2025年第3期157-165,共9页
为有效预判航行风险,并为船舶避碰、交通管理等决策提供重要依据,研究了一种基于多任务Informer模型的船舶轨迹预测及行为识别模型。该模型以Informer框架为基础,并引入多任务学习模式,通过设计多任务损失函数将船舶行为识别与轨迹预测... 为有效预判航行风险,并为船舶避碰、交通管理等决策提供重要依据,研究了一种基于多任务Informer模型的船舶轨迹预测及行为识别模型。该模型以Informer框架为基础,并引入多任务学习模式,通过设计多任务损失函数将船舶行为识别与轨迹预测并联训练,解决了AIS数据中船舶行为不准确无法作为模型输入的问题;在模型训练时,并设计基于同方差不确定性的损失函数自适应更新策略,自适应分配两个任务的损失权重。利用太仓航段水域中的真实AIS数据进行试验中多任务的Informer船舶轨迹预测模型在轨迹预测中的损失比LSTM和Informer模型分别降低了40.2%和14.7%;在行为识别任务中多任务模型的识别准确率比LSTM和Informer模型分别提升了11.7%和5.95%。表明了多任务模型能在有效提升船舶轨迹预测的性能的同时实现船舶对行为的准确识别。 展开更多
关键词 轨迹预测 行为识别 AIS数据 Informer模型 多任务学习
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基于融合劣化指标和VMD-Informer的水电机组劣化趋势预测
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作者 宋阿妮 陈亦真 +2 位作者 詹云峰 李超顺 付波 《中国农村水利水电》 北大核心 2025年第5期90-96,共7页
水电机组长期运行在恶劣环境下,异常振动更加频繁,逐渐出现疲劳、磨损,导致机组性能劣化。为保障机组的安全稳定运行,需要准确直观地反映水电机组运行并预测机组未来劣化状况,为机组状态检修提供重要依据。提出了一种基于融合劣化指标和... 水电机组长期运行在恶劣环境下,异常振动更加频繁,逐渐出现疲劳、磨损,导致机组性能劣化。为保障机组的安全稳定运行,需要准确直观地反映水电机组运行并预测机组未来劣化状况,为机组状态检修提供重要依据。提出了一种基于融合劣化指标和VMD-Informer的机组劣化趋势预测方法。首先构建KAN健康模型拟合工况参数与振摆值之间的映射关系,然后通过对比模型输出值与实测振摆值在不同指标下的差异得到多个劣化序列,运用遗传算法对多个劣化序列进行寻优获取融合劣化指标,兼顾多个指标的优势,更为准确地反映机组劣化趋势。之后用变分模态分解(VMD)将融合劣化序列分解为多个分量,最后利用Informer预测模型对分解后的各个分量进行多步预测并重构得到最终的预测结果,从而实现对机组运行状况的准确评估和预测。实例分析表明,所提方法能够生成可靠的劣化趋势,同时在预测上能学习劣化趋势序列的长期趋势和局部特征,预测精度更高。 展开更多
关键词 水电机组 劣化评估 退化预测 Kolmogorov-Arnold Network 遗传算法 INFORMER
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