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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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An Objective Synoptic Analysis Technique for the Identification of Tropical Cyclone Remote Precipitation in China and Its Application 被引量:1
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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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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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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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基于多尺度特征增强的航拍小目标检测算法 被引量:1
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作者 肖剑 何昕泽 +2 位作者 程鸿亮 杨小苑 胡欣 《浙江大学学报(工学版)》 北大核心 2026年第1期19-31,共13页
针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强... 针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强对小目标细粒度特征的捕获;基于PAN-FPN架构调整特征融合网络,增加对浅层特征的关注,同时引入多尺度卷积核增强对目标上下文信息的关注,以适应小目标检测场景;针对传统IoU灵活性、泛化性不强的问题,构建参数可调的Nin-IoU,通过引入可调参数,实现对IoU的针对性调整,以适应不同检测任务的需求;提出轻量化检测头,在增强多尺度特征信息交融的同时减少冗余信息的传递.结果表明,在VisDrone2019数据集上,所提算法以8.08×106的参数量实现了mAP0.5=50.3%的检测精度;相较于基准算法YOLOv8s,参数量降低了27.4%,精度提升了11.5个百分点.在DOTA与DIOR数据集上的实验结果表明,所提算法具有较强的泛化能力. 展开更多
关键词 目标检测 YOLOv8 无人机图像 特征融合 损失函数
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基于YOLOv8s多阶段算法的幼猪吮乳行为识别研究
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作者 陈创业 刘兹豪 +4 位作者 胡天让 谢晓丽 李洋 陈立涛 刘根新 《农机化研究》 北大核心 2026年第3期185-193,共9页
针对幼猪吮乳行为识别精度不足和个体目标跟踪困难的问题,采用以计算机视觉为基础的自动检测体系,整合YOLOv8s、DeepSORT、LSTM 3个算法模块,提出了一种多阶段的行为识别方法。首先,通过YOLOv8s对视频里的幼猪目标进行实时检测,再借助De... 针对幼猪吮乳行为识别精度不足和个体目标跟踪困难的问题,采用以计算机视觉为基础的自动检测体系,整合YOLOv8s、DeepSORT、LSTM 3个算法模块,提出了一种多阶段的行为识别方法。首先,通过YOLOv8s对视频里的幼猪目标进行实时检测,再借助DeepSORT算法来实行跨帧目标追踪并分配唯一标识;然后,把多张连续检测图片输入到LSTM模型里进行时序建模,从而判定出该段时间范围内的幼猪是否正在吮乳。于养殖场的母猪产房拍摄了26 320张照片、采集了4 930组行为序列数据集进行试验,结果表明,在mAP@0.5评价标准下,以YOLOv8s模型为基准的目标检测准确率为91.7%,召回率为92.3%,系统整体追踪准确值(MOTA)达到85.6%,且系统可在复杂的养殖环境下做到稳定运行。将该系统布置到云端平台上,可进行云端处理、数据可视化和远程监控等功能,即时展示每头幼猪的吮乳次数和时长,快速找出进食异常的幼猪个体,优化管理效率。 展开更多
关键词 幼猪行为识别 目标检测 多目标跟踪 时序模型 吮乳监测 智能养殖
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RIC-YOLOv8n:矿下料车超挂轻量化实时检测算法
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作者 丁玲 李露 +1 位作者 李永康 赵作鹏 《计算机工程与应用》 北大核心 2026年第2期371-383,共13页
针对矿井下作业环境复杂、光照不足、煤尘干扰等因素导致的传统目标检测算法在检测矿下料车超挂时表现不佳问题,提出了一种料车超挂轻量化实时检测算法RIC-YOLOv8n。使用轻量化模块C2f_RegNetY替换YOLOv8n中主干和颈部网络中的C2f模块,... 针对矿井下作业环境复杂、光照不足、煤尘干扰等因素导致的传统目标检测算法在检测矿下料车超挂时表现不佳问题,提出了一种料车超挂轻量化实时检测算法RIC-YOLOv8n。使用轻量化模块C2f_RegNetY替换YOLOv8n中主干和颈部网络中的C2f模块,减少了模型参数量并加快了模型推理速度;为了提高检测头的特征提取性能,采用联合信息对齐学习方法增强分类和回归任务的对齐能力;通过DeepSort进行矿下料车的目标追踪,设计了Residual_IBN模块替换DeepSort特征提取网络中的残差网络,提高了目标追踪的性能。通过自制的矿下料车检测与跟踪数据集进行算法验证,实验结果显示:RIC-YOLOv8n在矿下料车识别平均精度达到91.4%,基于RICYOLOv8n和改进的DeepSort目标追踪算法在多目标追踪准确率达到89.13%,检测速度达到61 FPS。提出的RICYOLOv8n和改进的DeepSort算法能较好的平衡检测速度与精度,适用于矿井下料车检测实时性作业的需要。 展开更多
关键词 目标检测 目标追踪 YOLOv8n 联合对齐解耦头 DeepSort 料车计数
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青贮饲料收获机自动跟随抛送系统研究现状与发展趋势 被引量:1
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作者 张姬 孙振洋 +3 位作者 宋占华 于镇伟 闫云鹏 田富洋 《农机化研究》 北大核心 2026年第2期284-292,共9页
青贮饲料因具有生产成本低、收获效益高、原料易得和营养均衡等优点,逐渐成为畜牧产业的主要饲料。传统青贮收获作业中人工依赖度高、抛料均匀性不足且抛送筒控制人员存在一定的安全隐患。青贮饲料收获机自动跟随抛送系统通过信息采集... 青贮饲料因具有生产成本低、收获效益高、原料易得和营养均衡等优点,逐渐成为畜牧产业的主要饲料。传统青贮收获作业中人工依赖度高、抛料均匀性不足且抛送筒控制人员存在一定的安全隐患。青贮饲料收获机自动跟随抛送系统通过信息采集设备实时获取料箱位置与环境动态信息,根据设定的青贮饲料填充模式进行抛送作业,解析填充状态,同时液压伺服控制系统根据识别定位情况动态调节抛送筒旋转角度与出料高度,实现青贮饲料落料点的控制。本文系统综述了当前国内外青贮饲料收获机自动跟随抛送系统的研究现状;分析了机器视觉、激光雷达与传感器在自动抛送系统中的工作原理与具体应用方法;针对我国青贮饲料收获机自动跟随抛送系统发展存在的问题,提出了研发多模态感知架构、开发高动态液压伺服系统与低惯量抛送筒材料、构建“青贮机-伴随车”群体协同作业模式的建议;同时,对青贮饲料收获机自动跟随抛送系统的发展方向进行预测,以期为我国青贮饲料收获机自动跟随抛送系统的研究提供参考。 展开更多
关键词 青贮饲料收获机 自动跟随抛送系统 机器视觉 激光雷达 目标检测
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基于OBE理念的聚合物加工原理课程教学设计
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作者 张文政 康海澜 +2 位作者 于智 杨凤 芦贺 《云南化工》 2026年第1期139-142,共4页
聚合物加工原理是高分子类学科必修的一门课程,不同高校依据研究方向的差异对该课程制定了不同的教学目标及培养要求,因此在新工科背景下,结合“两性一度”的金课标准,针对聚合物加工原理课程建设问题进行了课程改革与实践,对教学要素... 聚合物加工原理是高分子类学科必修的一门课程,不同高校依据研究方向的差异对该课程制定了不同的教学目标及培养要求,因此在新工科背景下,结合“两性一度”的金课标准,针对聚合物加工原理课程建设问题进行了课程改革与实践,对教学要素和教学环节进行规划,形成不同形式的教案,以满足不同高分子学科研究方向的要求,有助于教学效果的充分展现。以学校材料化工、材料加工工程、高分子化学与物理等专业的聚合物加工原理课程教学设计的要素进行分析,以期为开设聚合物加工原理课程的院校在教学设计时提供借鉴和参考。 展开更多
关键词 教学目标 培养目标 以成果为导向的教育 教学设计
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NCMM:基于非中心预测策略和极大值合并的目标检测网络
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作者 齐林 林潇 张倩倩 《计算机工程与应用》 北大核心 2026年第3期163-174,共12页
目标检测是计算机视觉领域的重要分支,它需要对图像中的目标完成分类与定位。单阶段目标检测速度较快,但也存在预测框与真实框误差过大的问题,并且在对小、遮挡、密集目标检测时的效果较差。当前的研究主要聚焦于网络架构的优化,但取得... 目标检测是计算机视觉领域的重要分支,它需要对图像中的目标完成分类与定位。单阶段目标检测速度较快,但也存在预测框与真实框误差过大的问题,并且在对小、遮挡、密集目标检测时的效果较差。当前的研究主要聚焦于网络架构的优化,但取得的提升有限。提出基于非中心的目标检测框架,采用非中心的预测框推理策略、基于图像分割标签的样本划分策略以及极大值合并的后处理方法。该优化方法具有较强的泛化能力,可以运用在各类使用全卷积神经网络的单阶段目标检测器上。进行了消融实验以验证上述方法的有效性,并在不同尺度的基线模型上进行了对比实验。结果表明,在不提升计算消耗且使用相同主干网络的前提下,AP^(50-95)与AP^(50)分别平均提升了1.6与2.38个百分点。 展开更多
关键词 目标检测 神经网络 YOLO
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WTNet-YOLO:结合离散小波变换与Transformer的棉田害虫检测算法
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作者 刘江涛 周刚 +2 位作者 刘浩南 王佳佳 贾振红 《计算机工程与应用》 北大核心 2026年第3期226-240,共15页
棉花生长过程中受到害虫严重危害,因此精准的害虫检测已成为智慧农业体系中的关键环节。其中大量棉田害虫属于小目标,特征提取困难,而且害虫个体之间存在显著的尺寸差异,这限制了现有目标检测算法的性能。提出了一种结合离散小波变换与T... 棉花生长过程中受到害虫严重危害,因此精准的害虫检测已成为智慧农业体系中的关键环节。其中大量棉田害虫属于小目标,特征提取困难,而且害虫个体之间存在显著的尺寸差异,这限制了现有目标检测算法的性能。提出了一种结合离散小波变换与Transformer的YOLO11目标检测算法——WTNet-YOLO(wavelet and Transformer network-YOLO)。融合部分卷积与多尺度深度卷积构建C3K2-MKPF模块,增强对多尺寸目标的特征提取能力。在颈部结合小波域融合模块(wavelet domain fusion module,WDFM)和跨阶段部分局部和全局模块(cross stage partial local and global block,CSP-LGB),提升各尺寸害虫的频域信息表达与全局信息定位。引入多尺度自适应空间注意门(multi-scale adaptive spatial attention gate,MASAG),动态融合主干与颈部的跨层特征,强化空间与语义信息表达。为验证相关方法,构建了一个棉田害虫数据集YST-PestCotton(yellow sticky trap pest dataset in cotton),涵盖多个尺寸范围的害虫,具有显著的尺度多样性,害虫像素面积最大可相差1200多倍。实验表明,在YST-PestCotton上mAP50提升了3.1个百分点,同时将害虫按目标框面积划分为0~256、256~512、512~1024和大于1024四个子集,mAP50分别提升2.4、1.3、1.5、3个百分点。在公开数据集Yellow sticky traps上mAP50达到了最高的95.3%。综合来看,WTNet-YOLO能够有效应对小目标内部的尺寸差异,同时兼顾不同尺寸害虫的检测需求。 展开更多
关键词 智慧农业 害虫检测 小目标 多尺寸
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基于改进RT-DETR的叶菜干烧心症状检测方法
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作者 林开颜 周纪元 +4 位作者 吴军辉 杨学军 陈杰 司慧萍 祝华军 《农业工程学报》 北大核心 2026年第1期201-209,共9页
植物工厂中叶菜常出现干烧心胁迫症状,针对现有方法在症状初期检测性能不佳的问题,该研究提出一种干烧心症状检测模型RT-DETR-TB(real-time detection transformer for tip-burn)。模型采用基于星运算学习范式的StarNet作为主干网络,实... 植物工厂中叶菜常出现干烧心胁迫症状,针对现有方法在症状初期检测性能不佳的问题,该研究提出一种干烧心症状检测模型RT-DETR-TB(real-time detection transformer for tip-burn)。模型采用基于星运算学习范式的StarNet作为主干网络,实现模型轻量化并加速收敛。颈部编码网络中,联合星运算和通道先验注意力(channel prior convolutional attention,CPCA)设计星注意力特征融合模块(star-attention feature fusion,SAFF),以提升多尺度特征融合效果;并设计跨尺度边缘增强模块(cross-scale edge enhance,CSEE),利用浅层边缘特征信息改善小目标检测性能。试验结果表明,RT-DETR-TB的参数量为16.4M,检测速度达58帧/s,平均精度从86.0%提升至88.4%,小目标精度从46.8%提升至50.7%。同时在不同植物工厂光照环境中,模型对比主流检测方法展现出更好的准确性和鲁棒性。该模型能够满足干烧心症状的早期预警需求,为植物工厂自动化生产提供技术支持。 展开更多
关键词 目标检测 模型 干烧心 RT-DETR 植物工厂
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育种新时代水稻杂交育种技术与策略探讨
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作者 吕文彦 程海涛 +1 位作者 马兆惠 田淑华 《中国农业科学》 北大核心 2026年第2期233-238,共6页
随着时间与技术的发展,作物育种经历了1.0到4.0世代,正向育种5.0世代发展。目前,虽然育种3.0世代和育种4.0世代得到广泛重视,但只有育种2.0世代的杂交育种才能够使亲本实现全基因组重组,出现基因内和基因间大量的、复杂的和不可预见的互... 随着时间与技术的发展,作物育种经历了1.0到4.0世代,正向育种5.0世代发展。目前,虽然育种3.0世代和育种4.0世代得到广泛重视,但只有育种2.0世代的杂交育种才能够使亲本实现全基因组重组,出现基因内和基因间大量的、复杂的和不可预见的互作,可能这才是导致突破性性状产生的基础,因此,在育种新时代背景下,杂交育种依然占有重要地位。但目前,以水稻为例,在科学性和有效性方面,广大育种工作者在杂交育种操作上仍然存在提高的空间。为选育高产、优质、多抗品种,克服品种的同质化,水稻杂交育种应注意以下几点:(1)育种目标要结合当地的自然条件,协调有利性状组配,使高产、优质、多抗的目标性状与具体品种相结合,避免品种同质化。(2)由于F_(1)综合双亲优良性状且具有一定的杂种优势,可能是同一组合表现最好的世代,F_(1)综合表现不良,其后代很难出现符合育种目标的期望类型。因此,此世代应作为一个重点选择世代,有利于提高育种效率。(3)在育种早代,因为主要是进行世代的促进,为提高育种效能,应采取直播形式,从而节省土地和资源。而育种中代应与早代测验相结合,以增强预见性,进一步筛选组合,提高育种效率。(4)高世代选择时,应在田间筛选后,进一步在室内比较组合间的穗部性状,选出最优组合,以实现优中选优。(5)育种5.0世代的智能型品种就是能够适应广域环境的生态与生物因子,并能满足生产需要的广适性品种,由于作物生长环境条件的复杂性,为实现广适性育种目标,应对品种进行多年、多点的广泛鉴定。总之,通过优化杂交育种的田间操作和选择技术,会大大提高育种效率,为选育出突破性品种奠定基础。 展开更多
关键词 水稻 杂交育种 育种目标 选择技术 世代促进 广适性
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改进NSGA-Ⅱ求解带准备时间的单元调度问题
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作者 张利平 孙睿 唐秋华 《机械设计与制造》 北大核心 2026年第1期180-185,共6页
随着个性化定制日益膨胀和绿色制造管控日渐规范,具有柔性、可重构、缩短产品制造周期的单元制造模式逐步在多品种小批量制造企业流行,从而提升企业利润和核心竞争力。然而,如何安排单元间的生产排程与AGV调度是本问题的关键。这里针对... 随着个性化定制日益膨胀和绿色制造管控日渐规范,具有柔性、可重构、缩短产品制造周期的单元制造模式逐步在多品种小批量制造企业流行,从而提升企业利润和核心竞争力。然而,如何安排单元间的生产排程与AGV调度是本问题的关键。这里针对带准备时间的单元调度问题,以交货期惩罚最小和车间总能耗最少为目标,建立了该问题的混合整数规划模型,提出了混合三种邻域结构的改进NSGA-Ⅱ算法求解该问题。首先,为了保证可行解的性能,设计了双层编码和基于时间重叠的解码机制;其次,设计了具有自适应交叉和变异概率、重启机制,有效保留优良基因片段,增强算法探索能力,防止算法早熟。最后,基于反转世代距离IGD和覆盖度C两个指标,对比其它算法,案例测试结果表明,所提算法具有良好的收敛性与分布性。 展开更多
关键词 单元调度 多目标优化 改进的NSGA-II 准备时间 自动引导小车
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基于改进YOLOv8的遥感影像变电站目标识别
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作者 刘润杰 许慧娜 +2 位作者 胡宇 王一 谢国钧 《郑州大学学报(工学版)》 北大核心 2026年第1期33-40,共8页
针对现有研究多集中于变电站局部结构检测而缺乏大区域快速发现与动态监测的问题,通过高分辨率卫星影像实现变电站的高效识别,提升电网安全隐患排查能力。首先构建了基于高分辨率光学卫星影像的变电站目标检测样本库;随后提出改进的YOL... 针对现有研究多集中于变电站局部结构检测而缺乏大区域快速发现与动态监测的问题,通过高分辨率卫星影像实现变电站的高效识别,提升电网安全隐患排查能力。首先构建了基于高分辨率光学卫星影像的变电站目标检测样本库;随后提出改进的YOLOv8算法,在骨干网络中嵌入SimAM轻量级注意力模块以增强细部特征聚焦能力,并将颈部结构替换为Efficient-RepGFPN,结合DySample动态上采样模块设计新型颈部结构GDFPN,以解决多层级特征语义错位问题。实验结果表明:改进方法优于主流检测算法,mAP 75和mAP 50-95分别提升至96.8%和87.1%,验证了其在变电站检测任务中的优越性。所提出的改进YOLOv8方法可有效支持大区域变电站的快速发现与动态监测,为电网安全管理提供了可靠的技术支撑。 展开更多
关键词 YOLOv8 遥感影像 目标检测 变电站 注意力机制
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