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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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GFRF R-CNN:Object Detection Algorithm for Transmission Lines
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作者 Xunguang Yan Wenrui Wang +3 位作者 Fanglin Lu Hongyong Fan Bo Wu Jianfeng Yu 《Computers, Materials & Continua》 SCIE EI 2025年第1期1439-1458,共20页
To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related issues.The increasing resolution of drone-cap... To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related issues.The increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution images.This study presents an enhanced object detection algorithm based on the Faster Regionbased Convolutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical components like insulators,shock hammers,and screws in transmission line.The algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine details.The Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and speed.The incorporation of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s accuracy.Experimental results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase compared to the standard Faster R-CNN.This highlights the effectiveness of the proposed algorithm in identifying electrical components in high-resolution aerial images. 展开更多
关键词 Faster R-cNN transmission line object detection GIOU GFR
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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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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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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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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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Railway-CLIP:A multimodal model for abnormal object detection in high-speed railway
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作者 Jiayu Zhang Qingji Guan +2 位作者 Junbo Liu Yaping Huang Jianyong Guo 《High-Speed Railway》 2025年第3期194-204,共11页
Automated detection of suspended anomalous objects on high-speed railway catenary systems using computer vision-based technology is a critical task for ensuring railway transportation safety. Despite the critical impo... Automated detection of suspended anomalous objects on high-speed railway catenary systems using computer vision-based technology is a critical task for ensuring railway transportation safety. Despite the critical importance of this task, conventional vision-based foreign object detection methodologies have predominantly concentrated on image data, neglecting the exploration and integration of textual information. The currently popular multimodal model Contrastive Language-Image Pre-training (CLIP) employs contrastive learning to enable simultaneous understanding of both visual and textual modalities. Drawing inspiration from CLIP’s capabilities, this paper introduces a novel CLIP-based multimodal foreign object detection model tailored for railway applications, referred to as Railway-CLIP. This model leverages CLIP’s robust generalization capabilities to enhance performance in the context of catenary foreign object detection. The Railway-CLIP model is primarily composed of an image encoder and a text encoder. Initially, the Segment Anything Model (SAM) is employed to preprocess raw images, identifying candidate bounding boxes that may contain foreign objects. Both the original images and the detected candidate bounding boxes are subsequently fed into the image encoder to extract their respective visual features. In parallel, distinct prompt templates are crafted for both the original images and the candidate bounding boxes to serve as textual inputs. These prompts are then processed by the text encoder to derive textual features. The image and text encoders collaboratively project the multimodal features into a shared semantic space, facilitating the computation of similarity scores between visual and textual representations. The final detection results are determined based on these similarity scores, ensuring a robust and accurate identification of anomalous objects. Extensive experiments on our collected Railway Anomaly Dataset (RAD) demonstrate that the proposed Railway-CLIP outperforms previous state-of-the-art methods, achieving 97.25% AUROC and 92.66% F1-score, thereby validating the effectiveness and superiority of the proposed approach in real-world high-speed railway anomaly detection scenarios. 展开更多
关键词 High-speed railway catenary systems Anomalous object detection Multimodal model Railway-cLIP
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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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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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工艺参数对Al_(2)O_(3)-C耐火材料抗氧化性和抗水化性的影响
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作者 张瑞 孙旭东 +5 位作者 魏瀚 袁彪 王俊涛 袁林 刘士范 陈松林 《耐火材料》 北大核心 2025年第1期65-69,共5页
为了研究各因素对Al_(2)O_(3)-C耐火材料抗氧化和抗水化性能的影响,以优化其制备工艺,以板状刚玉、Al粉、电熔锆刚玉、活性氧化铝粉、鳞片石墨为主要原料,使用热固性酚醛树脂为结合剂,采用液压成型制成?50 mm×50 mm的圆柱体试样,... 为了研究各因素对Al_(2)O_(3)-C耐火材料抗氧化和抗水化性能的影响,以优化其制备工艺,以板状刚玉、Al粉、电熔锆刚玉、活性氧化铝粉、鳞片石墨为主要原料,使用热固性酚醛树脂为结合剂,采用液压成型制成?50 mm×50 mm的圆柱体试样,在埋碳气氛下对试样进行了热处理。选取Al粉加入量(加入质量分数分别为6%、9%和12%)、石墨加入量(加入质量分数分别为5%、15%和25%)、热处理温度(680、950、1 500℃)和保温时间(3、6、9 h)为研究因素,每个因素选取3个水平进行正交设计,分析了其对Al_(2)O_(3)-C耐火材料抗氧化和抗水化性能的影响。结果表明:1)Al粉加入量和石墨加入量为影响抗氧化性能的主要因素,而热处理温度和保温时间为次要因素;2)Al粉加入量和热处理温度是影响抗水化性能的主要因素,而石墨加入量和保温时间为次要因素;3)综合考虑,最优工艺为:Al粉加入量9%(w),石墨加入量5%(w),热处理温度1 500℃,保温时间6 h,制备的试样中存在柱状的Al_(4)O_(4)C,能够显著提高材料的抗氧化和抗水化性能。 展开更多
关键词 Al_(2)O_(3)-c耐火材料 Al_(4)O_(4)C 抗水化性能 抗氧化性能
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基于改进YOLOv9-c的路面混合病害算法
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作者 张颖 王纪旭 +2 位作者 曹迎康 李罡 方有亮 《科学技术与工程》 北大核心 2025年第18期7793-7802,共10页
针对坑槽和裂缝两种路面病害检测实时性差、准确率低、易误检漏检等问题,提出了一种改进YOLOv9的路面混合病害算法,实现路面裂缝的自动化检测和识别。首先,在骨干网络中引入AKConv(alterable kernel convolution)替换RepNCSPELAN4中的... 针对坑槽和裂缝两种路面病害检测实时性差、准确率低、易误检漏检等问题,提出了一种改进YOLOv9的路面混合病害算法,实现路面裂缝的自动化检测和识别。首先,在骨干网络中引入AKConv(alterable kernel convolution)替换RepNCSPELAN4中的卷积模块,提高网络对不同病害的特征提取能力,有效解决路面病害与背景环境特征难以区分的问题;其次,在检测头中引入了SimAM注意力机制(selective image attention mechanism)和DySample上采样模块,提高网络聚焦特性并增强提取关键特征信息的能力;最后,采用inner-IoU函数优化模型的权重参数,提升对混合样本的学习能力。实验结果表明,改进后的模型与YOLOv9-c相比较,性能有了显著提升,平均精度提升40.17%、召回率提高了15.99%、mAP模型精度提高了20.95%,该优化算法能够更加精准高效的对路面混合病害进行检测,提高了路面病害检测的准确率和泛用性。 展开更多
关键词 YOLOv9-c 路面混合病害 注意力 特征提取 损失函数
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血清VEGF-C、PDGF水平对瘢痕子宫产妇再次妊娠分娩结局的预测价值
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作者 李凯 王振东 +2 位作者 赵雪琴 巨霞 程林凤 《分子诊断与治疗杂志》 2025年第7期1275-1277,1281,共4页
目的探讨血清血管内皮生长因子-C(VEGF-C)、血小板衍生生长因子(PDGF)水平对瘢痕子宫产妇再次妊娠分娩结局的预测价值。方法选取2020年7月至2024年6月于临汾市人民医院分娩的182例瘢痕子宫产妇作为研究对象,根据再次妊娠分娩结局分为结... 目的探讨血清血管内皮生长因子-C(VEGF-C)、血小板衍生生长因子(PDGF)水平对瘢痕子宫产妇再次妊娠分娩结局的预测价值。方法选取2020年7月至2024年6月于临汾市人民医院分娩的182例瘢痕子宫产妇作为研究对象,根据再次妊娠分娩结局分为结局良好组(n=118)和结局不良组(n=64)。比较两组产妇血清VEGF-C、PDGF水平;采用受试者工作特性(ROC)曲线评估血清VEGF-C、PDGF对分娩结局的预测价值;采用二分类Logistic回归分析探讨分娩结局的影响因素。结果结局不良组血清VEGF-C水平低于结局良好组,PDGF水平高于结局良好组,差异有统计学意义(P<0.05)。血清VEGF-C联合PDGF预测瘢痕子宫产妇再次妊娠分娩结局的曲线下面积(AUC)为0.902,高于单个指标预测(0.749、0.876)。结局不良组年龄≥30岁、产前体质指数≥30 kg/m^(2)、子宫肌层厚度≥4 mm、有流产史所占的比例均大于结局良好组,距上次剖宫产时间小于结局良好组,差异有统计学意义(P<0.05)。多因素分析显示,年龄≥30岁、子宫肌层厚度≥4 mm、VEGF-C降低、PDGF升高是瘢痕子宫产妇再次妊娠不良分娩结局的危险因素(P<0.05)。结论血清VEGF-C降低、PDGF升高与瘢痕子宫产妇再次妊娠不良分娩结局密切相关,二者可作为预测瘢痕子宫产妇再次妊娠分娩结局的重要指标。 展开更多
关键词 血管内皮生长因子-c 血小板衍生生长因子 瘢痕子宫
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DP7-C/DOTAP脂质体增强溶瘤腺病毒抗肿瘤效用的研究
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作者 胡蝶 苍玉德 杨莉 《中国医药生物技术》 2025年第S2期1-11,共11页
目的利用DP7-C/DOTAP脂质体作为腺病毒运载工具,一方面通过DP7-C/DOTAP脂质体增强溶瘤腺病毒转染CAR受体低表达肿瘤细胞,克服溶瘤腺病毒在转染细胞时受到的CAR限制,提高转染效率;另一方面通过用DP7-C/DOTAP脂质体包裹溶瘤腺病毒,保护溶... 目的利用DP7-C/DOTAP脂质体作为腺病毒运载工具,一方面通过DP7-C/DOTAP脂质体增强溶瘤腺病毒转染CAR受体低表达肿瘤细胞,克服溶瘤腺病毒在转染细胞时受到的CAR限制,提高转染效率;另一方面通过用DP7-C/DOTAP脂质体包裹溶瘤腺病毒,保护溶瘤腺病毒不被中和抗体清除。验证两方面增强溶瘤腺病毒的“溶瘤”作用。方法采用薄膜分散法制备DP7-C修饰的DOTAP脂质体(DP7-C/DOTAP),将腺病毒(Ad)与DP7-C/DOTAP脂质体在体外孵育形成DP7-C/DOTAP/Ad复合物。对DP7-C/DOTAP/Ad复合物的粒径、电位和形态学进行表征。然后在体外检测DP7-C/DOTAP/Ad复合物转染CAR受体低表达肿瘤细胞的效率及抵抗腺病毒中和抗体的功效。最后在小鼠中验证DP7-C/DOTAP脂质体促进溶瘤腺病毒H101的抗肿瘤效果。结果DP7-C/DOTAP脂质体其粒径分布在140~200 nm,电位为48~58 mV,透射电镜结果显示DP7-C/DOTAP/Ad复合物制备成功。与Ad相比,DP7-C/DOTAP/Ad复合物可显著提高低表达CAR受体卵巢癌细胞SKOV3的转染效率,同时DP7-C/DOTAP脂质体可以起到保护腺病毒不被中和抗体识别和清除的作用。在SKOV3卵巢癌皮下移植瘤模型中,单独H101组抑瘤率为23.90%,H101/DP7-C/DOTAP组抑瘤率为54.81%,可更好地抑制肿瘤生长(P<0.05)。结论DP7-C/DOTAP脂质体包裹腺病毒可增强腺病毒的转染效率和杀伤效果。DP7-C/DOTAP脂质体可有效促进腺病毒转染CAR低表达细胞。DP7-C/DOTAP脂质体可以对腺病毒起到良好的保护效果,不被抗腺病毒中和抗体中和。在动物实验中初步证明采用DP7-C/DOTAP脂质体能够增强溶瘤病毒的抗肿瘤效用。 展开更多
关键词 溶瘤腺病毒 DP7-c/DOTAP阳离子脂质体 卵巢癌
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基于PERK-eIF2α-ATF4-CHOP通路探讨中医药干预糖尿病肾病的作用机制
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作者 王茂泓 郑航 +1 位作者 李雪 张珍珍 《科学技术与工程》 北大核心 2025年第8期3079-3088,共10页
糖尿病肾病发病机制复杂,最终可进展为终末期肾病,给患者带来沉重负担,目前的治疗手段疗效有限。蛋白激酶R样内质网激酶(protein kinase RNA-like endoplasmic reticulum kinase, PERK)-真核翻译起始因子2α激酶(eukaryotic initiation ... 糖尿病肾病发病机制复杂,最终可进展为终末期肾病,给患者带来沉重负担,目前的治疗手段疗效有限。蛋白激酶R样内质网激酶(protein kinase RNA-like endoplasmic reticulum kinase, PERK)-真核翻译起始因子2α激酶(eukaryotic initiation factor-2α, eIF2α)-转录激活因子4(activating transcription factor 4,ATF4)-C/EBP同源蛋白(C/EBP-homologous protein, CHOP)信号通路作为内质网应激的关键通路,其下游调控的细胞凋亡和自噬等病理过程与糖尿病肾病的进展关系密切。中医药通过益气养阴、健脾益肾、利水消肿、清热解毒、活血祛瘀等治法调控PERK-eIF2α-ATF4-CHOP通路,起到保护肾小球滤过屏障、减少毛细血管基底膜增厚、增加尿蛋白质重吸收、延缓肾间质纤维化的作用。阐释PERK-eIF2α-ATF4-CHOP信号通路在糖尿病肾病中的作用机制,归纳中医治法干预该通路的理论基础,总结中药有效成分干预该通路的作用机制的研究进展,旨在为中医药防治糖尿病肾病提供新的思路和方法。 展开更多
关键词 中医药 糖尿病肾病 内质网应激 蛋白激酶R样内质网激酶-c/EBP同源蛋白(PERK-cHOP)信号通路
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基于ATD-CNN模型的黄河郑州段水面漂浮物检测研究
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作者 邵晓艳 王军 +2 位作者 赵雪专 王胜 冯军 《人民黄河》 北大核心 2025年第2期131-136,共6页
针对水面漂浮物感知目标小、易受干扰、识别精度低的问题,提出ATD-CNN目标检测模型。结合注意力机制,将注意力模块嵌入Faster R-CNN改进模型的基本主干网络,计算特征图内部特征点之间的长距离相关系数,对显著性特征进行有效增强,以提升... 针对水面漂浮物感知目标小、易受干扰、识别精度低的问题,提出ATD-CNN目标检测模型。结合注意力机制,将注意力模块嵌入Faster R-CNN改进模型的基本主干网络,计算特征图内部特征点之间的长距离相关系数,对显著性特征进行有效增强,以提升基本主干网络对图像特征的提取能力。基于河南省郑州市惠济区南裹头黄河沿岸采集的图像数据,对ATD-CNN模型检测效果进行验证,并将该模型性能与Faster R-CNN改进模型、YOLOv5单阶段目标检测模型进行对比。结果表明:与Faster R-CNN改进模型相比,ATD-CNN模型对水面漂浮物的漏检率下降,其mAP值提升了6.80%,F1 Score平均值提升了2%。与YOLOv5X、Faster R-CNN改进模型相比,ATD-CNN模型的mAP值分别提升了2.91%、6.80%,有效提高了水面漂浮物检测精度。 展开更多
关键词 卷积神经网络 水面漂浮物 目标检测 注意力 黄河郑州段
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SMSTracker:A Self-Calibration Multi-Head Self-Attention Transformer for Visual Object Tracking 被引量:1
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作者 Zhongyang Wang Hu Zhu Feng Liu 《Computers, Materials & Continua》 SCIE EI 2024年第7期605-623,共19页
Visual object tracking plays a crucial role in computer vision.In recent years,researchers have proposed various methods to achieve high-performance object tracking.Among these,methods based on Transformers have becom... Visual object tracking plays a crucial role in computer vision.In recent years,researchers have proposed various methods to achieve high-performance object tracking.Among these,methods based on Transformers have become a research hotspot due to their ability to globally model and contextualize information.However,current Transformer-based object tracking methods still face challenges such as low tracking accuracy and the presence of redundant feature information.In this paper,we introduce self-calibration multi-head self-attention Transformer(SMSTracker)as a solution to these challenges.It employs a hybrid tensor decomposition self-organizing multihead self-attention transformermechanism,which not only compresses and accelerates Transformer operations but also significantly reduces redundant data,thereby enhancing the accuracy and efficiency of tracking.Additionally,we introduce a self-calibration attention fusion block to resolve common issues of attention ambiguities and inconsistencies found in traditional trackingmethods,ensuring the stability and reliability of tracking performance across various scenarios.By integrating a hybrid tensor decomposition approach with a self-organizingmulti-head self-attentive transformer mechanism,SMSTracker enhances the efficiency and accuracy of the tracking process.Experimental results show that SMSTracker achieves competitive performance in visual object tracking,promising more robust and efficient tracking systems,demonstrating its potential to providemore robust and efficient tracking solutions in real-world applications. 展开更多
关键词 Visual object tracking tensor decomposition TRANSFORMER self-attention
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h-BN对低碳Al_(2)O_(3)-C耐火材料性能的影响 被引量:1
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作者 罗益欣 王杏 +3 位作者 刘正龙 余超 邓承继 丁军 《耐火材料》 北大核心 2025年第1期13-18,共6页
针对低碳Al_(2)O_(3)-C耐火材料因碳含量的降低致使材料的抗氧化性能和抗侵蚀性能恶化,难以适应冶炼技术发展等问题,以电熔白刚玉、α-Al_(2)O_(3)微粉、Al粉、Si粉和鳞片石墨为主要原料,采用h-BN为添加剂制备低碳Al_(2)O_(3)-C耐火材... 针对低碳Al_(2)O_(3)-C耐火材料因碳含量的降低致使材料的抗氧化性能和抗侵蚀性能恶化,难以适应冶炼技术发展等问题,以电熔白刚玉、α-Al_(2)O_(3)微粉、Al粉、Si粉和鳞片石墨为主要原料,采用h-BN为添加剂制备低碳Al_(2)O_(3)-C耐火材料。研究h-BN的添加量(质量分数分别为0、1%、3%、5%)对低碳Al_(2)O_(3)-C耐火材料物相组成、抗氧化性能、抗侵蚀性能等的影响,并结合热力学模拟分析揭示h-BN对Al_(2)O_(3)-C耐火材料抗侵蚀性能的作用机制。结果表明:随着h-BN添加量的增加,试样经1 600℃热处理后内部陶瓷相含量增加;高温氧化环境下,h-BN促进了试样脱碳层中Al_(18)B_(4)O_(33)和Al_(6)Si_(2)O_(13)的生成,从而改善了耐火材料的抗氧化性能;h-BN通过提高熔渣黏度以及生成高熔点相来增强试样的抗侵蚀性能。 展开更多
关键词 Al_(2)O_(3)-c耐火材料 H-BN 抗氧化性能 抗侵蚀性能
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