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Visual method of analyzing COVID-19 case information using spatio-temporal objects with multi-granularity 被引量:2
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作者 CHEN Yunhai JIANG Nan +2 位作者 CAO Yibing YANG Zhenkai ZHAO Xinke 《Journal of Geographical Sciences》 SCIE CSCD 2021年第7期1059-1081,共23页
Coronavirus disease 2019(COVID-19)is continuing to spread globally and still poses a great threat to human health.Since its outbreak,it has had catastrophic effects on human society.A visual method of analyzing COVID-... Coronavirus disease 2019(COVID-19)is continuing to spread globally and still poses a great threat to human health.Since its outbreak,it has had catastrophic effects on human society.A visual method of analyzing COVID-19 case information using spatio-temporal objects with multi-granularity is proposed based on the officially provided case information.This analysis reveals the spread of the epidemic,from the perspective of spatio-temporal objects,to provide references for related research and the formulation of epidemic prevention and control measures.The case information is abstracted,descripted,represented,and analyzed in the form of spatio-temporal objects through the construction of spatio-temporal case objects,multi-level visual expressions,and spatial correlation analysis.The rationality of the method is verified through visualization scenarios of case information statistics for China,Henan cases,and cases related to Shulan.The results show that the proposed method is helpful in the research and judgment of the development trend of the epidemic,the discovery of the transmission law,and the spatial traceability of the cases.It has a good portability and good expansion performance,so it can be used for the visual analysis of case information for other regions and can help users quickly discover the potential knowledge this information contains. 展开更多
关键词 COVID-19 spatio-temporal objects MULTI-GRANULARITY case information VISUALIZATION visual analysis spatial correlation analysis
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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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Dynamic Gaussian process regression for spatio-temporal data based on local clustering 被引量:1
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作者 Binglin WANG Liang YAN +3 位作者 Qi RONG Jiangtao CHEN Pengfei SHEN Xiaojun DUAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第12期245-257,共13页
This paper introduces techniques in Gaussian process regression model for spatiotemporal data collected from complex systems.This study focuses on extracting local structures and then constructing surrogate models bas... This paper introduces techniques in Gaussian process regression model for spatiotemporal data collected from complex systems.This study focuses on extracting local structures and then constructing surrogate models based on Gaussian process assumptions.The proposed Dynamic Gaussian Process Regression(DGPR)consists of a sequence of local surrogate models related to each other.In DGPR,the time-based spatial clustering is carried out to divide the systems into sub-spatio-temporal parts whose interior has similar variation patterns,where the temporal information is used as the prior information for training the spatial-surrogate model.The DGPR is robust and especially suitable for the loosely coupled model structure,also allowing for parallel computation.The numerical results of the test function show the effectiveness of DGPR.Furthermore,the shock tube problem is successfully approximated under different phenomenon complexity. 展开更多
关键词 Gaussian processes Surrogate model spatio-temporal systems Shock tube problem Local modeling strategy Time-based spatial clustering
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Object Extraction Based on Evolutionary Morphological Processing 被引量:1
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作者 LIBin PANLi 《Geo-Spatial Information Science》 2004年第3期193-197,230,共6页
This paper introduces a novel technique for object detection using genetic algorithms and morphological processing. The method employs a kind of object oriented structure element, which is derived by genetic algorithm... This paper introduces a novel technique for object detection using genetic algorithms and morphological processing. The method employs a kind of object oriented structure element, which is derived by genetic algorithms. The population of morphological filters is iteratively evaluated according to a statistical performance index corresponding to object extraction ability, and evolves into an optimal structuring element using the evolution principles of genetic search. Experimental results of road extraction from high resolution satellite images are presented to illustrate the merit and feasibility of the proposed method. 展开更多
关键词 object extraction genetic algorithms morphological processing high resolution satellite images
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Multi-objective optimization of process parametersduring low-pressure die casting of AZ91Dmagnesium alloy wheel castings 被引量:12
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作者 Chen Zhang Yu Fu +1 位作者 Han Wang Hai Hao 《China Foundry》 SCIE 2018年第5期327-332,共6页
Multi-objective optimization has been increasingly applied in engineering where optimal decisions need to be made in the presence of trade-offs between two or more objectives. Minimizing the volume of shrinkage porosi... Multi-objective optimization has been increasingly applied in engineering where optimal decisions need to be made in the presence of trade-offs between two or more objectives. Minimizing the volume of shrinkage porosity, while reducing the secondary dendritic arm spacing of a wheel casting during low-pressure die casting(LPDC) process, was taken as an example of such problem. A commercial simulation software Pro CASTTM was applied to simulate the filling and solidification processes. Additionally, a program for integrating the optimization algorithm with numerical simulation was developed based on SiPESC. By setting pouring temperature and filling pressure as design variables, shrinkage porosity and secondary dendritic arm spacing as objective variables, the multi-objective optimization of minimum volume of shrinkage porosity and secondary dendritic arm spacing was achieved. The optimal combination of AZ91 D wheel casting was: pouring temperature 689 °C and filling pressure 6.5 kPa. The predicted values decreased from 4.1% to 2.1% for shrinkage porosity, and 88.5 μm to 81.2 μm for the secondary dendritic arm spacing. The optimal results proved the feasibility of the developed program in multi-objective optimization. 展开更多
关键词 magnesium alloy multi-objective optimization process parameters shrinkage porosity secondary DENDRITIC arm SPACING
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Multi-objective process parameter optimization for energy saving in injection molding process 被引量:4
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作者 Ning-yun LU Gui-xia GONG +1 位作者 Yi YANG Jian-hua LU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2012年第5期382-394,共13页
This paper deals with a multi-objective parameter optimization framework for energy saving in injection molding process.It combines an experimental design by Taguchi's method,a process analysis by analysis of vari... This paper deals with a multi-objective parameter optimization framework for energy saving in injection molding process.It combines an experimental design by Taguchi's method,a process analysis by analysis of variance(ANOVA),a process modeling algorithm by artificial neural network(ANN),and a multi-objective parameter optimization algorithm by genetic algorithm(GA)-based lexicographic method.Local and global Pareto analyses show the trade-off between product quality and energy consumption.The implementation of the proposed framework can reduce the energy consumption significantly in laboratory scale tests,and at the same time,the product quality can meet the pre-determined requirements. 展开更多
关键词 Injection molding process Energy saving Multi-objective optimization Genetic algorithm Lexicographic method
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Long-Term Tracking Based on Spatio-Temporal Context
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作者 陆佳辉 陈一民 +1 位作者 邹一波 邹国志 《Journal of Shanghai Jiaotong university(Science)》 EI 2017年第4期504-512,共9页
Aiming at the problem that the fast tracking algorithm using spatio-temporal context (STC) will inevitably lead to drift and even lose the target in long-term tracking, a new algorithm based on spatio-temporal context... Aiming at the problem that the fast tracking algorithm using spatio-temporal context (STC) will inevitably lead to drift and even lose the target in long-term tracking, a new algorithm based on spatio-temporal context that integrates long-term tracking with detecting is proposed in this paper. We track the target by the fast tracking algorithm, and the cascaded search strategy is introduced to the detecting part to relocate the target if the fast tracking fails. To a large extent, the proposed algorithm effectively improves the accuracy and stability of long-term tracking. Extensive experimental results on benchmark datasets show that the proposed algorithm can accurately track and relocate the target though the target is partially or completely occluded or reappears after being out of the scene. © 2017, Shanghai Jiaotong University and Springer-Verlag GmbH Germany. 展开更多
关键词 object tracking spatio-temporal context(STC) object detection cascaded search
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Object-Oriented Modeling for Product Developing Process and It's Management System
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作者 XIANG Fei NING Ruxin YAO Jun 《Journal of Beijing Institute of Technology》 EI CAS 2001年第4期412-417,共6页
To resolve the technical difficulty of managing the product devdoping process,an ob-ject model for product developing process is provided by using the object-oriented methodology.In this model,the constituent objects ... To resolve the technical difficulty of managing the product devdoping process,an ob-ject model for product developing process is provided by using the object-oriented methodology.In this model,the constituent objects including activity,transition,data,partidpant,applica-tion tool and resource as well as the rela tions between them are identified and discussed in detail.According to this model,a function framework of the process managing system is also proposed.Based on the object model and the function framework,product devdoping process and productinformation flow can be efficiently managed and controlled.As a result,costly errors and dupli-cate efforts are avoided in the product developing process,which is useful for shor tening develop-ment cyde and improving product quality. 展开更多
关键词 process management process object model process activity vir tual activity
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Modelling and Multi-Objective Optimal Control of Batch Processes Using Recurrent Neuro-fuzzy Networks 被引量:1
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作者 Jie Zhang 《International Journal of Automation and computing》 EI 2006年第1期1-7,共7页
In this paper, the modelling and multi-objective optimal control of batch processes, using a recurrent neuro-fuzzy network, are presented. The recurrent neuro-fuzzy network, forms a "global" nonlinear long-range pre... In this paper, the modelling and multi-objective optimal control of batch processes, using a recurrent neuro-fuzzy network, are presented. The recurrent neuro-fuzzy network, forms a "global" nonlinear long-range prediction model through the fuzzy conjunction of a number of "local" linear dynamic models. Network output is fed back to network input through one or more time delay units, which ensure that predictions from the recurrent neuro-fuzzy network are long-range. In building a recurrent neural network model, process knowledge is used initially to partition the processes non-linear characteristics into several local operating regions, and to aid in the initialisation of corresponding network weights. Process operational data is then used to train the network. Membership functions of the local regimes are identified, and local models are discovered via network training. Based on a recurrent neuro-fuzzy network model, a multi-objective optimal control policy can be obtained. The proposed technique is applied to a fed-batch reactor. 展开更多
关键词 Optimal control batch processes neural networks multi-objective optimisation.
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Integrated Building Envelope Design Process Combining Parametric Modelling and Multi-Objective Optimization 被引量:4
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作者 Dan Hou Gang Liu +2 位作者 Qi Zhang Lixiong Wang Rui Dang 《Transactions of Tianjin University》 EI CAS 2017年第2期138-146,共9页
As an important element in sustainable building design, the building envelope has been witnessing a constant shift in the design approach. Integrating multi-objective optimization (MOO) into the building envelope desi... As an important element in sustainable building design, the building envelope has been witnessing a constant shift in the design approach. Integrating multi-objective optimization (MOO) into the building envelope design process is very promising, but not easy to realize in an actual project due to several factors, including the complexity of optimization model construction, lack of a dynamic-visualization capacity in the simulation tools and consideration of how to match the optimization with the actual design process. To overcome these difficulties, this study constructed an integrated building envelope design process (IBEDP) based on parametric modelling, which was implemented using Grasshopper platform and interfaces to control the simulation software and optimization algorithm. A railway station was selected as a case study for applying the proposed IBEDP, which also utilized a grid-based variable design approach to achieve flexible optimum fenestrations. To facilitate the stepwise design process, a novel strategy was proposed with a two-step optimization, which optimized various categories of variables separately. Compared with a one-step optimization, though the proposed strategy performed poorly in the diversity of solutions, the quantitative assessment of the qualities of Pareto-optimum solution sets illustrates that it is superior. © 2016, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Architectural design BUILDINGS Computer software Design Intelligent buildings OPTIMIZATION Pareto principle Solar buildings
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A Scheme for Mining State Association Rules of Process Object Based on Big Data
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作者 Qiaoyun Song Qingbei Guo +3 位作者 Kai Wang Tao Du Shouning Qu Yong Zhang 《Journal of Computer and Communications》 2014年第14期17-24,共8页
This paper devises a scheme which can discover the state association rules of process object. The scheme aims to dig the hidden close relationships of different links in process object. We adopt a method based on diff... This paper devises a scheme which can discover the state association rules of process object. The scheme aims to dig the hidden close relationships of different links in process object. We adopt a method based on difference and extremum to compute the timing. Clustering is used to classifying the adjusted data, and the next is associating the clusters. Based on the rules of clusters, we produce the rules of links. Association degrees between each two links can be determined. It is easy to get association chains according to the degree. The state association rules that can be obtained in accordance with association rules are the final results. Some industry guidance can be directly summarized from the state association rules, and we can apply the guidance to improve the efficiency of production and operational in allied industries. 展开更多
关键词 process object TIMING ASSOCIATION Chain STATE ASSOCIATION Rule
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A Genetic Algorithm for Single Machine Scheduling with Fuzzy Processing Time and Multiple Objectives
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作者 吴超超 顾幸生 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期185-189,共5页
In this paper, by considering the fuzzy nature of the data in real-life problems, single machine scheduling problems with fuzzy processing time and multiple objectives are formulated and an efficient genetic algorithm... In this paper, by considering the fuzzy nature of the data in real-life problems, single machine scheduling problems with fuzzy processing time and multiple objectives are formulated and an efficient genetic algorithm which is suitable for solving these problems is proposed. As illustrative numerical examples, twenty jobs processing on a machine is considered. The feasibility and effectiveness of the proposed method have been demonstrated in the simulation. 展开更多
关键词 SCHEDULING single machine genetic algorithms fuzzy processing time multiple objectives
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Energy retrofit and conservation of a historic building using multi-objective optimization and an analytic hierarchy process 被引量:4
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作者 Francesca Roberti Ulrich Filippi Oberegger +2 位作者 Elena Lucchi Alexandra Troi 侯恩哲 《建筑节能》 CAS 2017年第3期9-9,共1页
When deciding on the best historic building retrofit,energy savings and thermal comfort can be quantitatively evaluated using an energy model,whereas conservation compatibility is intrinsically qualitative and reflect... When deciding on the best historic building retrofit,energy savings and thermal comfort can be quantitatively evaluated using an energy model,whereas conservation compatibility is intrinsically qualitative and reflects the perspective of the local heritage authority. We present a methodology that permits finding and comparing optimal retrofits for historic buildings in a multi-perspective and quantitative way. We use an analytic hierarchyprocess to quantify conservation compatibility by distilling a conservation score from the opinions of 10 experts in the field. This score,along with energy needs for heating and cooling and thermal comfort,are the three targets of a multi-objective optimization aimed at identifying optimal retrofits for a medieval building in the north of Italy,destined to become a museum. Retrofit measures considered were different kinds of external and internal envelope insulation,improvement of airtightness,replacement of windows,and ventilative cooling. The result is a portfolio of optimal retrofits that cover the whole range of conservation compatibility. We showthat in the analyzed case heritage preservation is compatible with a four-fold reduction in energy needs at a high thermal comfort level. Even higher energy savings are only achievable at the cost of heritage degradation. 展开更多
关键词 《建筑节能》 英文摘要 编辑工作 期刊
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Multi-Objective Optimization Using Genetic Algorithms of Multi-Pass Turning Process 被引量:1
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作者 Abdelouahhab Jabri Abdellah El Barkany Ahmed El Khalfi 《Engineering(科研)》 2013年第7期601-610,共10页
In this paper we present a multi-optimization technique based on genetic algorithms to search optimal cuttings parameters such as cutting depth, feed rate and cutting speed of multi-pass turning processes. Tow objecti... In this paper we present a multi-optimization technique based on genetic algorithms to search optimal cuttings parameters such as cutting depth, feed rate and cutting speed of multi-pass turning processes. Tow objective functions are simultaneously optimized under a set of practical of machining constraints, the first objective function is cutting cost and the second one is the used tool life time. The proposed model deals multi-pass turning processes where the cutting operations are divided into multi-pass rough machining and finish machining. Results obtained from Genetic Algorithms method are presented in Pareto frontier graphic;this technique helps us in decision making process. An example is presented to illustrate the procedure of this technique. 展开更多
关键词 GENETIC Algorithms Mutli-objective Optimization TURNING process MACHINING
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Tufting Carpet Machine Information Model Based on Object Linking and Embedding for Process Control Unified Architecture
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作者 GUO Xiang CHI Xinfu SUN Yize 《Journal of Donghua University(English Edition)》 CAS 2021年第1期43-50,共8页
In view of the lack of research on the information model of tufting carpet machine in China,an information modeling method based on Object Linking and Embedding for Process Control Unified Architecture(OPC UA)framewor... In view of the lack of research on the information model of tufting carpet machine in China,an information modeling method based on Object Linking and Embedding for Process Control Unified Architecture(OPC UA)framework was proposed to solve the problem of“information island”caused by the differentiated data interface between heterogeneous equipment and system in tufting carpet machine workshop.This paper established an information model of tufting carpet machine based on analyzing the system architecture,workshop equipment composition and information flow of the workshop,combined with the OPC UA information modeling specification.Subsequently,the OPC UA protocol is used to instantiate and map the information model,and the OPC UA server is developed.Finally,the practicability of tufting carpet machine information model under the OPC UA framework and the feasibility of realizing the information interconnection of heterogeneous devices in the tufting carpet machine digital workshop are verified.On this basis,the cloud and remote access to the underlying device data are realized.The application of this information model and information integration scheme in actual production explores and practices the application of OPC UA technology in the digital workshop of tufting carpet machine. 展开更多
关键词 tufting carpet machine digital workshop information model object Linking and Embedding for process Control Unified Architecture(OPC UA) INTERCONNECTION
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Dynamic Multi-objective Optimization of Chemical Processes Using Modified BareBones MOPSO Algorithm
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作者 杜文莉 王珊珊 +1 位作者 陈旭 钱锋 《Journal of Donghua University(English Edition)》 EI CAS 2014年第2期184-189,共6页
Dynamic multi-objective optimization is a complex and difficult research topic of process systems engineering. In this paper,a modified multi-objective bare-bones particle swarm optimization( MOBBPSO) algorithm is pro... Dynamic multi-objective optimization is a complex and difficult research topic of process systems engineering. In this paper,a modified multi-objective bare-bones particle swarm optimization( MOBBPSO) algorithm is proposed that takes advantage of a few parameters of bare-bones algorithm. To avoid premature convergence,Gaussian mutation is introduced; and an adaptive sampling distribution strategy is also used to improve the exploratory capability. Moreover, a circular crowded sorting approach is adopted to improve the uniformity of the population distribution.Finally, by combining the algorithm with control vector parameterization,an approach is proposed to solve the dynamic optimization problems of chemical processes. It is proved that the new algorithm performs better compared with other classic multiobjective optimization algorithms through the results of solving three dynamic optimization problems. 展开更多
关键词 dynamic multi-objective optimization bare-bones particle swarm optimization(PSO) algorithm chemical process
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Implementing Convolutional Neural Networks to Detect Dangerous Objects in Video Surveillance Systems
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作者 Carlos Rojas Cristian Bravo +1 位作者 Carlos Enrique Montenegro-Marín Rubén González-Crespo 《Computers, Materials & Continua》 2025年第12期5489-5507,共19页
The increasing prevalence of violent incidents in public spaces has created an urgent need for intelligent surveillance systems capable of detecting dangerous objects in real time.While traditional video surveillance ... The increasing prevalence of violent incidents in public spaces has created an urgent need for intelligent surveillance systems capable of detecting dangerous objects in real time.While traditional video surveillance relies on human monitoring,this approach suffers from limitations such as fatigue and delayed response times.This study addresses these challenges by developing an automated detection system using advanced deep learning techniques to enhance public safety.Our approach leverages state-of-the-art convolutional neural networks(CNNs),specifically You Only Look Once version 4(YOLOv4)and EfficientDet,for real-time object detection.The system was trained on a comprehensive dataset of over 50,000 images,enhanced through data augmentation techniques to improve robustness across varying lighting conditions and viewing angles.Cloud-based deployment on Amazon Web Services(AWS)ensured scalability and efficient processing.Experimental evaluations demonstrated high performance,with YOLOv4 achieving 92%accuracy and processing images in 0.45 s,while EfficientDet reached 93%accuracy with a slightly longer processing time of 0.55 s per image.Field tests in high-traffic environments such as train stations and shopping malls confirmed the system’s reliability,with a false alarm rate of only 4.5%.The integration of automatic alerts enabled rapid security responses to potential threats.The proposed CNN-based system provides an effective solution for real-time detection of dangerous objects in video surveillance,significantly improving response times and public safety.While YOLOv4 proved more suitable for speed-critical applications,EfficientDet offered marginally better accuracy.Future work will focus on optimizing the system for low-light conditions and further reducing false positives.This research contributes to the advancement of AI-driven surveillance technologies,offering a scalable framework adaptable to various security scenarios. 展开更多
关键词 Automatic detection of objects convolutional neural networks deep learning real-time image processing video surveillance systems automatic alerts
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目光注视影响客体注意的认知机制:客体加工方式的作用
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作者 赵晶晶 闫驰 +2 位作者 高云飞 王璐瑶 王勇慧 《心理与行为研究》 北大核心 2026年第1期23-31,共9页
已有研究表明目光注视影响客体注意,但这种影响的内部机制是直视捕获还是维持注意至今仍无定论,究其原因,是由于这些研究中使用的客体加工方式(整体vs.特征加工)不同。因此,本研究包含4个实验,采用双框线索范式,通过操纵SOA为300 ms、60... 已有研究表明目光注视影响客体注意,但这种影响的内部机制是直视捕获还是维持注意至今仍无定论,究其原因,是由于这些研究中使用的客体加工方式(整体vs.特征加工)不同。因此,本研究包含4个实验,采用双框线索范式,通过操纵SOA为300 ms、600 ms和900 ms,在整体加工(实验1和2)和特征加工(实验3和4)客体中考察以上问题。四个实验结果一致表明,600 ms SOA直视比回避条件均产生更大的客体注意效应,说明目光注视对客体注意的影响具有普遍性。但整体加工客体中直视更能捕获注意,支持了感觉增强理论;特征加工客体中直视更能维持注意,支持了注意转移理论,表明目光注视对客体注意的影响因客体加工方式的不同又具有特异性。 展开更多
关键词 目光注视 客体注意 双框线索范式 整体加工 特征加工
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多目标海洋环境预报技术发展趋势和启示
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作者 李毅能 朱宇航 +9 位作者 彭世球 陈植武 韦惺 李骏旻 李少钿 谢培炜 廖嘉文 龚延昆 唐世林 蔡树群 《中国科学院院刊》 北大核心 2026年第1期107-119,共13页
随着“海洋强国”战略的稳步推进,以及全球海洋活动的不断拓展,海洋环境安全保障已成为国家的重大战略需求。深海的温度、盐度、声速,以及海浪、内孤立波、近岸裂流等环境信息,对航行安全和水下装备的运用有着至关重要的影响。传统的单... 随着“海洋强国”战略的稳步推进,以及全球海洋活动的不断拓展,海洋环境安全保障已成为国家的重大战略需求。深海的温度、盐度、声速,以及海浪、内孤立波、近岸裂流等环境信息,对航行安全和水下装备的运用有着至关重要的影响。传统的单一要素预报模式,已难以满足多目标环境保障的需求。为此,发展一套涵盖基础海洋要素预报(温盐流场),以及特定过程灾害预警(拍岸浪、裂流、内孤立波等)的多目标、高分辨率预报技术体系,成为必然的发展趋势。近年来,人工智能技术的迅猛发展及其与传统数值模拟、数据同化技术的深度交叉融合,正在成为推动该领域技术革新的新范式。文章系统地梳理了多目标海洋预报技术的发展脉络与前沿动态,总结了国内外的进展情况,剖析了核心挑战,并从观测网络、预报模式和学科融合等维度提出了发展启示,旨在为构建自主可控、世界领先的新一代海洋环境安全保障体系提供参考。 展开更多
关键词 多目标预报技术 特定过程预警 水下环境信息 海洋环境安全保障
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基于改进YOLOv11n的复杂场景下行人检测模型
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作者 刘伟 时薇 +3 位作者 杨淼 王井阳 黄敏 杨琳 《河北科技大学学报》 北大核心 2026年第1期60-72,共13页
针对由于光照、角度、背景干扰及行人目标太小等复杂场景的影响会导致行人检测精度下降,容易出现误检或漏检等问题,提出了一种基于改进YOLOv11n的行人检测模型YOLOv11-CREP。首先,引入由Conv卷积和空间深度转化卷积(space-to-depth conv... 针对由于光照、角度、背景干扰及行人目标太小等复杂场景的影响会导致行人检测精度下降,容易出现误检或漏检等问题,提出了一种基于改进YOLOv11n的行人检测模型YOLOv11-CREP。首先,引入由Conv卷积和空间深度转化卷积(space-to-depth convolution,SPDConv)融合形成的CSPDConv,使模型减少信息的丢失并增强对重要细节的提取;其次,给出RepNCSPELAN4-GC模块(其利用幽灵卷积GhostConv对RepNCSPELAN4进行改进,以减少RepNCSPELAN4模块的参数量),并用改进后的RepNCSPELAN4-GC模块来替换Neck层部分C3k2模块;再次,将高效多尺度注意力(efficient multi-scale attention,EMAttention)和并行网络注意力(parallel network attention,ParNetAttention)融合成新的EMPAttention注意力模块,以增强模型对小目标行人的检测能力;最后,针对小目标行人和遮挡目标的特性,新增小目标检测头P2来增强模型对小目标的识别能力。结果表明:YOLOv11-CREP与原始的YOLOv11n模型相比,平均精度(mean average precision,mAP)在IoU阈值0.5时提升4.6个百分点,达到95.3%;在IoU阈值范围为0.5~0.95时提升9.0个百分点,达到70.2%。所提模型兼顾高检测性能和实时性要求,有效提升了复杂场景下的行人检测性能,为行人检测任务建模提供了参考。 展开更多
关键词 计算机图像处理 YOLOv11n 行人检测 复杂场景 注意力机制 小目标检测
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