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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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A Novel Reliable and Trust Objective Function for RPL-Based IoT Routing Protocol
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作者 Mariam A.Alotaibi Sami S.Alwakeel Aasem N.Alyahya 《Computers, Materials & Continua》 2025年第2期3467-3497,共31页
The Internet of Things (IoT) integrates diverse devices into the Internet infrastructure, including sensors, meters, and wearable devices. Designing efficient IoT networks with these heterogeneous devices requires the... The Internet of Things (IoT) integrates diverse devices into the Internet infrastructure, including sensors, meters, and wearable devices. Designing efficient IoT networks with these heterogeneous devices requires the selection of appropriate routing protocols, which is crucial for maintaining high Quality of Service (QoS). The Internet Engineering Task Force’s Routing Over Low Power and Lossy Networks (IETF ROLL) working group developed the IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) to meet these needs. While the initial RPL standard focused on single-metric route selection, ongoing research explores enhancing RPL by incorporating multiple routing metrics and developing new Objective Functions (OFs). This paper introduces a novel Objective Function (OF), the Reliable and Secure Objective Function (RSOF), designed to enhance the reliability and trustworthiness of parent selection at both the node and link levels within IoT and RPL routing protocols. The RSOF employs an adaptive parent node selection mechanism that incorporates multiple metrics, including Residual Energy (RE), Expected Transmission Count (ETX), Extended RPL Node Trustworthiness (ERNT), and a novel metric that measures node failure rate (NFR). In this mechanism, nodes with a high NFR are excluded from the parent selection process to improve network reliability and stability. The proposed RSOF was evaluated using random and grid topologies in the Cooja Simulator, with tests conducted across small, medium, and large-scale networks to examine the impact of varying node densities. The simulation results indicate a significant improvement in network performance, particularly in terms of average latency, packet acknowledgment ratio (PAR), packet delivery ratio (PDR), and Control Message Overhead (CMO), compared to the standard Minimum Rank with Hysteresis Objective Function (MRHOF). 展开更多
关键词 IOT LLNs RPL objective function OF MRHOF OF0 routing metrics RELIABILITY trustworthiness
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An Objective Method for Temperature and Wind Forecast at the Venues of the 14 th National Winter Games
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作者 Xuefeng YANG Sitong LIU 《Meteorological and Environmental Research》 2025年第2期59-61,共3页
According to the demand for weather forecast at the venues of the 14 th National Winter Games,based on the data of the fine grid model of the European Centre(EC)and RMAPS model,as well as the real-time observation dat... According to the demand for weather forecast at the venues of the 14 th National Winter Games,based on the data of the fine grid model of the European Centre(EC)and RMAPS model,as well as the real-time observation data of the competition fields,a dynamic optimal correction method was proposed to improve the accuracy rate of temperature and wind speed prediction.Through techniques such as deviation correction and univariate linear regression,mathematical models applicable to different competition regions were constructed,and the effective correction of objective forecast products within 0-120 h were realized.The results show that this method significantly improved the accuracy rate of the prediction of temperature,wind speed and extreme wind speed,and the effect was more obvious especially when the model performance was unstable.Meanwhile,terrain and climate background had a significant impact on the correction effect.This study provides new technical support for mountain meteorological forecast. 展开更多
关键词 Temperature forecast Wind speed forecast objective correction Dynamic optimum Mountain meteorology
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Correction Algorithm of Temperature Forecast Based on an Objective Optimal Scheme
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作者 Xuefeng YANG Sitong LIU 《Meteorological and Environmental Research》 2025年第2期56-58,共3页
The forecast results of temperature based on the intelligent grids of the Central Meteorological Observatory and the meteorological bureau of the autonomous region and the numerical forecast model of the European Cent... The forecast results of temperature based on the intelligent grids of the Central Meteorological Observatory and the meteorological bureau of the autonomous region and the numerical forecast model of the European Center(EC model)from February to December in 2022 were used.Based on the data of the national intelligent grid forecast,the intelligent grid forecast of the regional bureau,EC model,etc.,temperature was predicted.According to the research of the grid point forecast synthesis algorithm with the highest accuracy rate in the recent three days,the temperature grid point correction was conducted in two forms of stations and grids.In order to reduce the deviation caused by the seasonal system temperature difference,a temperature prediction model was established by using the rolling forecast errors of 5,10,15,20,25 and 30 d as the basis data.The verification and evaluation of objective correction results show that the accuracy rate of temperature forecast by the intelligent grid of the regional bureau,the national intelligent grid,and EC model could be increased by 10%,8%,and 12%,respectively. 展开更多
关键词 objective correction Optimal extraction Temperature correction Average sliding deviation
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Relationship between objective and subjective refraction measurements in patients with mild keratoconus
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作者 Masoud Khorrami-Nejad Ahmed Kamil Dakhil +3 位作者 Hesam Hashemian Masoud Sadeghi Reza Yousefi Foroozan Narooie-Noori 《International Journal of Ophthalmology(English edition)》 2025年第3期398-403,共6页
AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients ... AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients diagnosed with mild KCN.Objective dry retinoscopy using autorefractometer and subjective refraction measurements were performed.Sphere,cylinder,J0,J45,and spherical equivalent values were compared between the two techniques.RESULTS:The mean age of 68 patients with mild KCN was 21.32±5.03y(12–35y).There were 37(54.4%)males.Objective refraction yielded significantly more myopic sphere(-1.44 D vs-0.57 D),higher cylinder magnitude(-2.24 D vs-1.48 D),and more myopic spherical equivalent(-2.56 D vs-1.31 D)compared to subjective refraction(all P<0.05).The mean differences were-0.87 D for sphere,-0.76 D for cylinder,and-1.25 D for spherical equivalent.No significant differences were found for J0 and J45 values,indicating agreement in astigmatism axis(P>0.05).CONCLUSION:In patients with mild KCN,objective dry retinoscopy overestimates the degree of myopia and astigmatism compared to subjective refraction.The irregular cornea in KCN likely impacts objective measurements.Subjective refraction allows compensation for irregularity,providing a more accurate correction.When determining refractive targets,the tendency of objective methods to overcorrect should be considered. 展开更多
关键词 KERATOCONUS objective refraction subjective refraction
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An Objective Synoptic Analysis Technique for the Identification of Tropical Cyclone Remote Precipitation in China and Its Application
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作者 JIA Li DING Chenchen +2 位作者 CONG Chunhua REN Fumin LIU Yanan 《Journal of Ocean University of China》 2025年第1期13-30,共18页
At present,the identification of tropical cyclone remote precipitation(TRP)requires subjective participation,leading to inconsistent results among different researchers despite adopting the same identification standar... At present,the identification of tropical cyclone remote precipitation(TRP)requires subjective participation,leading to inconsistent results among different researchers despite adopting the same identification standard.Thus,establishing an objective identification method is greatly important.In this study,an objective synoptic analysis technique for TRP(OSAT_TRP)is proposed to identify TRP using daily precipitation datasets,historical tropical cyclone(TC)track data,and the ERA5 reanalysis data.This method includes three steps:first,independent rain belts are separated,and those that might relate to TCs'remote effects are distinguished according to their distance from the TCs.Second,the strong water vapor transport belt from the TC is identified using integrated horizontal water vapor transport(IVT).Third,TRP is distinguished by connecting the first two steps.The TRP obtained through this method can satisfy three criteria,as follows:1)the precipitation occurs outside the circulation of TCs,2)the precipitation is affected by TCs,and 3)a gap exists between the TRP and TC rain belt.Case diagnosis analysis,compared with subjective TRP results and backward trajectory analyses using HYSPLIT,indicates that OSAT_TRP can distinguish TRP even when multiple TCs in the Northwest Pacific are involved.Then,we applied the OSAT_TRP to select typical TRPs and obtained the synoptic-scale environments of the TRP through composite analysis. 展开更多
关键词 tropical cyclone remote precipitation objective identification method
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Two Performance Indicators Assisted Infill Strategy for Expensive Many⁃Objective Optimization
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作者 Yi Zhao Jianchao Zeng Ying Tan 《Journal of Harbin Institute of Technology(New Series)》 2025年第5期24-40,共17页
In recent years,surrogate models derived from genuine data samples have proven to be efficient in addressing optimization challenges that are costly or time⁃intensive.However,the individuals in the population become i... In recent years,surrogate models derived from genuine data samples have proven to be efficient in addressing optimization challenges that are costly or time⁃intensive.However,the individuals in the population become indistinguishable as the curse of dimensionality increases in the objective space and the accumulation of surrogate approximated errors.Therefore,in this paper,each objective function is modeled using a radial basis function approach,and the optimal solution set of the surrogate model is located by the multi⁃objective evolutionary algorithm of strengthened dominance relation.The original objective function values of the true evaluations are converted to two indicator values,and then the surrogate models are set up for the two performance indicators.Finally,an adaptive infill sampling strategy that relies on approximate performance indicators is proposed to assist in selecting individuals for real evaluations from the potential optimal solution set.The algorithm is contrasted against several advanced surrogate⁃assisted evolutionary algorithms on two suites of test cases,and the experimental findings prove that the approach is competitive in solving expensive many⁃objective optimization problems. 展开更多
关键词 expensive multi⁃objective optimization problems infill sample strategy evolutionary optimization algorithm
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Study on the Construction of Whole-course Nursing Objective Management System for Patients with Type 2 Diabetes
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作者 Lei Wu 《Journal of Clinical and Nursing Research》 2025年第1期203-208,共6页
Objective: To explore the effect of a whole-course nursing objective management system on disease control and quality of life in patients with type 2 diabetes, and to propose strategies for constructing such a system ... Objective: To explore the effect of a whole-course nursing objective management system on disease control and quality of life in patients with type 2 diabetes, and to propose strategies for constructing such a system for these patients. Methods: Ninety patients with type 2 diabetes admitted to the Department of Endocrinology of the hospital from January 2024 to June 2024 were selected. The control group (n = 45) received routine nursing care, while the observation group (n = 45) received whole-course nursing. Indicators such as glucose metabolism and compliance behavior were measured before and after care, and the health and quality of life of patients in both groups were evaluated. Results: A comparison of blood glucose levels and compliance behavior showed that the observation group had lower blood glucose levels than the control group (P < 0.05). Additionally, the compliance behavior score of the observation group was higher than that of the control group (P < 0.05). Conclusion: The holistic nursing model demonstrates significant nursing effects for patients with type 2 diabetes. This approach not only assists in blood sugar control, prevents disease progression, and reduces complications, but also enhances patients’ knowledge of health management, aiding in their recovery. 展开更多
关键词 Patients with type 2 diabetes Whole nursing Management system by objectives Construction path
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Dimensional synchronous modeling-based enhanced Kriging algorithm and adaptive Copula method for multi-objective synthetical reliability analyses
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作者 Cheng LU Yunwen FENG +1 位作者 Chengwei FEI Da TENG 《Chinese Journal of Aeronautics》 2025年第9期144-165,共22页
To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise mode... To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise modeling strategy,cell array operation principle,and Copula theory.Under this framework,we propose a DSM-based Enhanced Kriging(DSMEK)algorithm to synchronously derive the modeling of multi-objective,and explore an adaptive Copula function approach to analyze the correlation among multiple objectives and to assess the synthetical reliability level.In the proposed DSMEK and adaptive Copula methods,the Kriging model is treated as the basis function of DSMEK model,the Multi-Objective Snake Optimizer(MOSO)algorithm is used to search the optimal values of hyperparameters of basis functions,the cell array operation principle is adopted to establish a whole model of multiple objectives,the goodness of fit is utilized to determine the forms of Copula functions,and the determined Copula functions are employed to perform the reliability analyses of the correlation of multi-analytical objectives.Furthermore,three examples,including multi-objective complex function approximation,aeroengine turbine bladeddisc multi-failure mode reliability analyses and aircraft landing gear system brake temperature reliability analyses,are performed to verify the effectiveness of the proposed methods,from the viewpoints of mathematics and engineering.The results show that the DSMEK and adaptive Copula approaches hold obvious advantages in terms of modeling features and simulation performance.The efforts of this work provide a useful way for the modeling of multi-analytical objectives and synthetical reliability analyses of complex structure/system with multi-output responses. 展开更多
关键词 Adaptive Copula method Aeroengine turbine bladeddisc Aircraft landing gear system Correlation of multianalytical objectives Dimensional synchronous modeling-based enhanced Kriging algorithm Reliability analyses
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Efficient Resource Allocation in Cloud IaaS: A Multi-Objective Strategy for Minimizing Workflow Makespan and Cloud Resource Costs
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作者 Jean Edgard Gnimassoun Dagou Dangui Augustin Sylvain Legrand Koffi Akanza Konan Ricky N’dri 《Open Journal of Applied Sciences》 2025年第1期147-167,共21页
The ease of accessing a virtually unlimited pool of resources makes Infrastructure as a Service (IaaS) clouds an ideal platform for running data-intensive workflow applications comprising hundreds of computational tas... The ease of accessing a virtually unlimited pool of resources makes Infrastructure as a Service (IaaS) clouds an ideal platform for running data-intensive workflow applications comprising hundreds of computational tasks. However, executing scientific workflows in IaaS cloud environments poses significant challenges due to conflicting objectives, such as minimizing execution time (makespan) and reducing resource utilization costs. This study responds to the increasing need for efficient and adaptable optimization solutions in dynamic and complex environments, which are critical for meeting the evolving demands of modern users and applications. This study presents an innovative multi-objective approach for scheduling scientific workflows in IaaS cloud environments. The proposed algorithm, MOS-MWMC, aims to minimize total execution time (makespan) and resource utilization costs by leveraging key features of virtual machine instances, such as a high number of cores and fast local SSD storage. By integrating realistic simulations based on the WRENCH framework, the method effectively dimensions the cloud infrastructure and optimizes resource usage. Experimental results highlight the superiority of MOS-MWMC compared to benchmark algorithms HEFT and Max-Min. The Pareto fronts obtained for the CyberShake, Epigenomics, and Montage workflows demonstrate closer proximity to the optimal front, confirming the algorithm’s ability to balance conflicting objectives. This study contributes to optimizing scientific workflows in complex environments by providing solutions tailored to specific user needs while minimizing costs and execution times. 展开更多
关键词 Cloud Infrastructure Multi-objective Scheduling Resource Cost Optimization Resource Utilization Scientific Workflows
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Distributed Stochastic Optimization with Compression for Non-Strongly Convex Objectives
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作者 Xuanjie Li Yuedong Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期459-481,共23页
We are investigating the distributed optimization problem,where a network of nodes works together to minimize a global objective that is a finite sum of their stored local functions.Since nodes exchange optimization p... We are investigating the distributed optimization problem,where a network of nodes works together to minimize a global objective that is a finite sum of their stored local functions.Since nodes exchange optimization parameters through the wireless network,large-scale training models can create communication bottlenecks,resulting in slower training times.To address this issue,CHOCO-SGD was proposed,which allows compressing information with arbitrary precision without reducing the convergence rate for strongly convex objective functions.Nevertheless,most convex functions are not strongly convex(such as logistic regression or Lasso),which raises the question of whether this algorithm can be applied to non-strongly convex functions.In this paper,we provide the first theoretical analysis of the convergence rate of CHOCO-SGD on non-strongly convex objectives.We derive a sufficient condition,which limits the fidelity of compression,to guarantee convergence.Moreover,our analysis demonstrates that within the fidelity threshold,this algorithm can significantly reduce transmission burden while maintaining the same convergence rate order as its no-compression equivalent.Numerical experiments further validate the theoretical findings by demonstrating that CHOCO-SGD improves communication efficiency and keeps the same convergence rate order simultaneously.And experiments also show that the algorithm fails to converge with low compression fidelity and in time-varying topologies.Overall,our study offers valuable insights into the potential applicability of CHOCO-SGD for non-strongly convex objectives.Additionally,we provide practical guidelines for researchers seeking to utilize this algorithm in real-world scenarios. 展开更多
关键词 Distributed stochastic optimization arbitrary compression fidelity non-strongly convex objective function
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Effect of low-degree astigmatism on the objective visual quality
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作者 Ling-Ying Ye Shu-Feng Li +2 位作者 Jing-Jing Zuo Jin Li Hui-Xiang Ma 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1086-1093,共8页
AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corr... AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal vision.The cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism.OQAS was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.RESULTS:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed.The increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),respectively.The decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),respectively.At the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were lower.CONCLUSION:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality. 展开更多
关键词 low-degree astigmatism objective visual quality Optical Quality Analysis System
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Objective Model Selection in Physics: Exploring the Finite Information Quantity Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第5期1848-1889,共42页
Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Informati... Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines. 展开更多
关键词 Comparative Uncertainty Finite Information Quantity Formulating a Model Measurement Accuracy Limit objective Model Selection
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Research on the Relationship between the School-Running Characteristics of Private Colleges and Universities and the Development Objectives of the Government
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作者 Lishuxian Zhao Xiaoxia Wu Zhuolin Zhu 《Journal of Contemporary Educational Research》 2024年第9期296-302,共7页
The development objectives of the Chinese government have a guiding effect on the school-running characteristics of private colleges and universities.This paper explores the relationship between the characteristics of... The development objectives of the Chinese government have a guiding effect on the school-running characteristics of private colleges and universities.This paper explores the relationship between the characteristics of private colleges and universities and the development objectives of the provincial government,using Jiangsu Province as a case study.All the schools have the consciousness of fully considering the development objectives of Jiangsu Province when formulating the school-running characteristics.Their characteristics all contain some training methods,training courses,or institutional construction aiming at the development objectives.Most universities can support the government’s objectives on employment and innovation.Only a third of the schools provide government support for science research.Private colleges and universities should make full use of the free and flexible advantages of private education,combine them with the continuous changes of policies and markets,and create clear,scientific,and dynamic school-running characteristics,in order to achieve long-term development. 展开更多
关键词 Development objectives of the government School-running characteristics Chinese Private colleges and universities
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基于高空无人机平台的多模态跟踪数据集 被引量:2
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作者 肖云 曹丹 +2 位作者 李成龙 江波 汤进 《中国图象图形学报》 北大核心 2025年第2期361-374,共14页
目的无人机(unmanned aerial vehicle,UAV)因易操纵、灵活等特点,近年来在军事和民用等多个领域得到广泛应用。相对于低空无人机,高空无人机具有更广的视野,更强的隐蔽性,在情报侦察、灾害救援等方面具有更高的应用价值。然而,现有无人... 目的无人机(unmanned aerial vehicle,UAV)因易操纵、灵活等特点,近年来在军事和民用等多个领域得到广泛应用。相对于低空无人机,高空无人机具有更广的视野,更强的隐蔽性,在情报侦察、灾害救援等方面具有更高的应用价值。然而,现有无人机多模态目标跟踪研究主要针对低空无人机,缺乏高空无人机多模态目标跟踪数据集,限制了该领域的研究和发展。方法构建了一个用于评估高空无人机多模态目标跟踪方法的数据集HiAl(high altitude UAV multi-modal tracking dataset),该数据集主要由搭载混合传感器的无人机在500 m高空拍摄的可见光—红外多模态视频构成,两种模态数据经过精确配准和帧级标注,可以较好地评估不同多模态目标跟踪方法在高空无人机平台下的性能表现。结果将主流的12种多模态跟踪方法在所提数据集与非高空无人机场景数据集上的表现进行了比较,方法TBSI(template-bridged search region interaction)在RGBT234数据集(RGBthermal dataset)上PR(precision rate)值达到0.871,而在本文所提数据集上仅0.527,下降了39.5%,其SR(success rate)值由RGBT234数据集上的0.637,下降到本文所提数据集上的0.468,下降了26.5%。方法HMFT(hierarchical multi-modal fusion tracker)在所提数据集上的PR与RGBT234相比下降了23.6%,SR下降了14%。此外,利用HiAl数据集对6个方法进行重新训练实验,所有重训练方法的性能均得到提升。结论本文提出一个基于高空无人机平台的多模态目标跟踪数据集,旨在促进多模态目标跟踪在高空无人机上的应用研究。HiAl数据集的在线发布地址为:https://github.com/mmic-lcl/Datasets-and-benchmark-code/tree/main。 展开更多
关键词 多模态目标跟踪 高空无人机 微小目标 高质量配准 数据集
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基于改进YOLOv8的果园复杂环境下苹果检测模型研究 被引量:2
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作者 岳有军 漆潇 +1 位作者 赵辉 王红君 《南京信息工程大学学报》 北大核心 2025年第1期31-41,共11页
为了使采摘机器人能够在果园复杂环境下(如不同光照条件、叶子遮挡、密集的苹果群和超远视距等场景)对成熟程度各异的苹果果实进行快速且精确的检测,本文提出一种基于改进YOLOv8的苹果果实检测模型.首先,将EMA注意力机制模块集成到YOLOv... 为了使采摘机器人能够在果园复杂环境下(如不同光照条件、叶子遮挡、密集的苹果群和超远视距等场景)对成熟程度各异的苹果果实进行快速且精确的检测,本文提出一种基于改进YOLOv8的苹果果实检测模型.首先,将EMA注意力机制模块集成到YOLOv8模型中,使模型更加关注待检测果实区域,抑制背景和枝叶遮挡等一般特征信息,提高被遮挡果实的检测准确率;其次,使用提取特征更加高效的三支路DWR模块对原始C2f模块进行替换,通过多尺度特征融合方法提高小目标检测能力;同时结合DAMO-YOLO的思想,对原始YOLOv8颈部进行重构,实现高层语义和低层空间特征的高效融合;最后,使用Inner-SIoU损失函数对模型进行优化,提高识别精度.在复杂的果园环境中,以苹果作为检测对象,实验结果表明:本文所提算法在测试集下的查准率、召回率、mAP_(0.5)、mAP_(0.5~0.95)以及F1分数分别达到86.1%、89.2%、94.0%、64.4%和87.6%,改进后的算法在大部分指标上均优于原始模型.在不同数量果实场景下的对比实验结果表明,该方法具有优异的鲁棒性. 展开更多
关键词 模式识别 深度学习 目标检测 YOLOv8
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基于注意力机制和特征融合的井下轻量级人员检测方法 被引量:3
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作者 王帅 杨伟 +2 位作者 李宇翔 吴佳奇 杨维 《煤炭科学技术》 北大核心 2025年第4期383-392,共10页
煤矿井下环境复杂,安全隐患较多,人员检测是保障煤矿安全生产和建设智慧矿山的重要内容。常用的检测算法不仅参数量大,对设备算力要求高,而且在煤矿低照度环境下的应用效果不理想。针对上述问题,基于YOLOv5提出一种用于煤矿井下的轻量... 煤矿井下环境复杂,安全隐患较多,人员检测是保障煤矿安全生产和建设智慧矿山的重要内容。常用的检测算法不仅参数量大,对设备算力要求高,而且在煤矿低照度环境下的应用效果不理想。针对上述问题,基于YOLOv5提出一种用于煤矿井下的轻量级人员检测方法YOLOv5-CWG。首先,在骨干网络中嵌入坐标注意力机制(Coordinate Attention)自适应的调整特征图中每个通道的权重,增强特征的表达能力,提高模型在低照度、粉尘影响严重以及对比度低的不利条件下对待检测人员目标的关注度,更精确地定位和识别人员目标。其次,通过加权多尺度特征融合模块(Weighted multiscale feature fusion moule)引入可学习的权重赋予特征层不同的关注度,使网络有效融合浅层位置特征和高层语义信息,增强模型的信息提取能力,更好地区分目标区域和背景噪声,从而提高模型的抗干扰能力。增加1个P2层的检测头,提升较小目标的检测和定位精度。引入SIoU损失函数代替原损失函数加快模型收敛。最后,引入Ghost模块优化骨干网络,可以在不损失模型性能的前提下降低模型的参数量,提高检测速度,使得模型更容易部署在资源受限的设备上。结果表明,提出的YOLOv5-CWG算法在煤矿井下人员检测数据集(UMPDD)上的mAP达到了97.5%,相较于YOLOv5s提高了7.3%,计算量减少了27.6%,FPS提高了6.3。所提算法显著提高了煤矿井下人员检测精度,有效解决了亮度低和光照不均引起的人员检测困难问题。 展开更多
关键词 人员检测 YOLOv5 注意力机制 轻量化 特征融合
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基于FPGA的MobileNetV1目标检测加速器设计 被引量:3
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作者 严飞 郑绪文 +2 位作者 孟川 李楚 刘银萍 《现代电子技术》 北大核心 2025年第1期151-156,共6页
卷积神经网络是目标检测中的常用算法,但由于卷积神经网络参数量和计算量巨大导致检测速度慢、功耗高,且难以部署到硬件平台,故文中提出一种采用CPU与FPGA融合结构实现MobileNetV1目标检测加速的应用方法。首先,通过设置宽度超参数和分... 卷积神经网络是目标检测中的常用算法,但由于卷积神经网络参数量和计算量巨大导致检测速度慢、功耗高,且难以部署到硬件平台,故文中提出一种采用CPU与FPGA融合结构实现MobileNetV1目标检测加速的应用方法。首先,通过设置宽度超参数和分辨率超参数以及网络参数定点化来减少网络模型的参数量和计算量;其次,对卷积层和批量归一化层进行融合,减少网络复杂性,提升网络计算速度;然后,设计一种八通道核间并行卷积计算引擎,每个通道利用行缓存乘法和加法树结构实现卷积运算;最后,利用FPGA并行计算和流水线结构,通过对此八通道卷积计算引擎合理的复用完成三种不同类型的卷积计算,减少硬件资源使用量、降低功耗。实验结果表明,该设计可以对MobileNetV1目标检测进行硬件加速,帧率可达56.7 f/s,功耗仅为0.603 W。 展开更多
关键词 卷积神经网络 目标检测 FPGA MobileNetV1 并行计算 硬件加速
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基于时空实体的空间信息系统 被引量:1
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作者 张江水 华一新 曹一冰 《测绘科学》 北大核心 2025年第2期11-18,共8页
针对当前时空信息系统的研究仍主要基于传统地理信息系统(GIS)的理论和方法,仅进行了一些新技术补充和扩展的问题,该文在分析了当前GIS理论与方法面对的主要问题和挑战的基础上,提出了一种全新的基于时空实体的空间信息系统理论,兼容当... 针对当前时空信息系统的研究仍主要基于传统地理信息系统(GIS)的理论和方法,仅进行了一些新技术补充和扩展的问题,该文在分析了当前GIS理论与方法面对的主要问题和挑战的基础上,提出了一种全新的基于时空实体的空间信息系统理论,兼容当前GIS技术,并从数据模型、关键技术、软件平台和应用实践等方面阐述构建这一全新的时空信息系统的方法。实验结果表明,基于时空实体的空间信息系统开创了全新的空间信息系统研究范式,有利推动地理信息系统向新一代空间信息系统的跨越式发展。 展开更多
关键词 时空实体 时空对象 多粒度时空对象 地理信息系统 空间信息系统 相关性
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基于视觉相机和激光雷达融合的无人车障碍物检测与跟踪研究 被引量:2
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作者 魏超 吴西涛 +3 位作者 朱耿霆 舒用杰 李路兴 随淑鑫 《机械工程学报》 北大核心 2025年第2期296-309,320,共15页
为提高无人车障碍物检测跟踪的精度和稳定性,首先针对YOLO v5(You only look once version 5,YOLO v5)网络存在的语义信息和候选框信息丢失的问题,引入深度可分离空洞空间金字塔结构与目标框加权融合算法完成对网络的优化;其次针对单阶... 为提高无人车障碍物检测跟踪的精度和稳定性,首先针对YOLO v5(You only look once version 5,YOLO v5)网络存在的语义信息和候选框信息丢失的问题,引入深度可分离空洞空间金字塔结构与目标框加权融合算法完成对网络的优化;其次针对单阶段障碍物点云聚类精度低的问题,设计一种考虑点云距离与外轮廓连续性的两阶段障碍物点云聚类方法并完成三维包围盒的建立;最后将注意力机制引入MobileNet使网络更加聚焦于目标对象特有的视觉特征,并综合利用视觉特征和三维点云信息共同构建关联性度量指标,提高匹配精度。利用KITTI数据集对构建的障碍物目标检测、跟踪与测速算法进行仿真测试,并搭建实车平台进行真实环境试验,验证所提算法的有效性和真实环境可迁移性。 展开更多
关键词 视觉相机 激光雷达 目标检测 多目标跟踪 无人车
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