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基因panel在新生儿疑似遗传代谢疾病中的应用
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作者 魏莹 容志惠 陈玲 《医药导报》 CAS 北大核心 2024年第12期1965-1970,共6页
目的探讨基因panel在患有疑似遗传代谢疾病新生儿中的应用。方法对华中科技大学同济医学院附属同济医院2023年1月—2024年3月收治的有遗传代谢高危临床表型的新生儿,采用基因panel检测,同时搜集其临床资料并进行随访观察,分析致病基因... 目的探讨基因panel在患有疑似遗传代谢疾病新生儿中的应用。方法对华中科技大学同济医学院附属同济医院2023年1月—2024年3月收治的有遗传代谢高危临床表型的新生儿,采用基因panel检测,同时搜集其临床资料并进行随访观察,分析致病基因的检出情况、患儿基因型与表型的一致性等。结果该研究共纳入53例有遗传代谢高危征象的新生儿,其中致病基因阳性的总体检出率为17.0%(9/53),常见检出的致病基因有氯离子通道基因(CLCN1)、双氧化酶2基因(DUOX2)、间隙连接蛋白β2基因(GJB2)、酪氨酸蛋白磷酸酶非受体11型基因(PTPN11)、钠通道α亚基基因(SCN1A)、痉挛截瘫基因11(SPG11)等,其中DUOX2和GJB2检出比例最高,分别为33.3%(3/9)和22.2%(2/9)。将致病基因阳性组患儿与阴性组患儿进行对比分析,阳性组患儿临床表型个数可能更多,预后相较于基因阴性组也更严重。在致病基因阳性组患儿中,除了病例1和病例9因相关疾病发病较晚导致临床表型与致病基因暂时不相符,其余病例致病基因与临床表型均符合。结论基因panel具有耗时短、检测成本及技术难度低等特点,适用于发展中国家及经济水平相对落后地区疑似遗传代谢疾病患儿的早期筛查。 展开更多
关键词 基因panel 遗传代谢病 基因检测 新生儿 早期筛查
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Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model 被引量:1
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作者 Er-feng Zhao Xin Li Chong-shi Gu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期177-186,共10页
Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and ... Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in China.Subsequently,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect characteristics.These findings revealed the governing mechanism of main factors.Furthermore,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch dams.This model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation differences.Ultimately,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam performance.Additionally,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably interpreted.Validation of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan dam.The findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures. 展开更多
关键词 Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion panel data model
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Energy dissipation mechanism and ballistic characteristic optimization in foam sandwich panels against spherical projectile impact
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作者 Jianqiang Deng Tao Liu +4 位作者 Liming Chen Xin Pan Jingzhe Wang Shaowei Zhu Weiguo Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期108-122,共15页
This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element method.Based on th... This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element method.Based on the geometric topology of the FSP system,three FSP configurations with the same areal density are derived,namely multi-layer,gradient core and asymmetric face sheet,and three key structural parameters are identified:core thickness(t_(c)),face sheet thickness(t_(f))and overlap face/core number(n_(o)).The ballistic performance of the FSP system is comprehensively evaluated in terms of the ballistic limit velocity(BLV),deformation modes,energy dissipation mechanism,and specific penetration energy(SPE).The results show that the FSP system exhibits a significant configuration dependence,whose ballistic performance ranking is:asymmetric face sheet>gradient core>multi-layer.The mass distribution of the top and bottom face sheets plays a critical role in the ballistic resistance of the FSP system.Both BLV and SPE increase with tf,while the raising tcor noleads to an increase in BLV but a decrease in SPE.Further,a face-core synchronous enhancement mechanism is discovered by the energy dissipation analysis,based on which the ballistic optimization procedure is also conducted and a design chart is established.This study shed light on the anti-penetration mechanism of the FSP system and might provide a theoretical basis for its engineering application. 展开更多
关键词 Sandwich panel Numerical simulation Ballistic resistance Specific penetration energy Energy analysis
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Mechanical Behavior of Panels Reinforced with Orthogonal Plant Fabrics: Experimental and Numerical Assessment
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作者 Martha L.Sánchez G.Capote 《Journal of Renewable Materials》 EI CAS 2024年第10期1791-1810,共20页
The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional materials.The production of cement,steel,a... The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional materials.The production of cement,steel,and other conventional materials impacts both ecosystems and human health,increasing the demand for ecological and biodegradable alternatives.In this paper,we analyze the properties of panels made from a combination of plant fibers and castor oil resin,analyzing the viability of their use as construction material.For the research,orthogonal fabrics made with waste plant fibers supplied by a company that deals with the manufacture of furniture and craft products were used.These fabrics were made with strips of plant fibers of the Calamus rotang,Bambusa vulgaris,Heteropsis flexuosa,and Salix viminalis species.To improve their compatibility with the castor oil resin,a cold argon plasma treatment was applied.The effect of the treatment on the properties of the fibers and the panels was analyzed.The density,water absorption capacity,and swelling percentage were evaluated.Tensile,compression,static bending,and linear buckling tests were carried out.The study found that panels made with treated fiber fabrics exhibited a reduction of approximately 10%in absorption capacity and up to 35%in swelling percentage values.Panels made with Bambusa vulgaris fabrics exhibited the highest strength and stiffness values.Numerical models were constructed using commercial finite element software.When comparing the numerical results with the experimental ones,differences of less than 15%were seen,demonstrating that the models allow adequately predicting the analyzed properties.On comparing the values obtained with the characteristic values of oriented strand board,the results suggest that panels made with unconventional materials could replace commercial panels traditionally made with wood-based fibers and particles and other composite materials in several applications in the construction industry. 展开更多
关键词 Unconventional materials nonstructural panels plantfibers surface treatment physical properties mechanical properties
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Impact of Different Rooftop Coverings on Photovoltaic Panel Temperature
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作者 Aws Al-Akam Ahmed A.Abduljabbar Ali Jaber Abdulhamed 《Energy Engineering》 EI 2024年第12期3761-3777,共17页
Photovoltaic(PV)panels are essential to the global transition towards sustainable energy,offering a clean,renewable source that reduces reliance on fossil fuels and mitigates climate change.High temperatures can signi... Photovoltaic(PV)panels are essential to the global transition towards sustainable energy,offering a clean,renewable source that reduces reliance on fossil fuels and mitigates climate change.High temperatures can significantly affect the performance of photovoltaic(PV)panels by reducing their efficiency and power output.This paper explores the consequential effect of various rooftop coverings on the thermal performance of photovoltaic(PV)panels.It investigates the relationship between the type of rooftop covering materials and the efficiency of PV panels,considering the thermal performance and its implications for enhancing their overall performance and sustainability.The study compares four rooftop covering materials:wooden flakes packs(both dry and wet),polystyrene,and woolen insulation.The measurements were implemented under Iraqi weather conditions.The comparison was based on the PV panels’thermal behavior and its impact on conversion efficiency.The results revealed that covering the roof beneath the installed PV panels reduces their temperature and increases efficiency.The best performance was observedwhen placingwetwooden flakes beneath the panels,with an efficiency increase of 5%.Moreover,thewoolen insulation offered an efficiency rise of 12%near sunset.Themain outcome of thiswork is that the wet–wooden–flakes showed the best performance improvement of the PV panels. 展开更多
关键词 Solar energy PV panels thermal performance rooftop covering
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How R&D investment promotes green technology innovation in the context of digitalization?-An empirical analysis based on provincial panel data
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作者 LIU Jie LI Zhi-hui WEI Fang-xin 《Ecological Economy》 2024年第1期39-52,共14页
Green technology innovation is an important driving force and source to promote my country’s high-quality development,and it is the core path to achieve sustainable development.This paper uses my country’s provincia... Green technology innovation is an important driving force and source to promote my country’s high-quality development,and it is the core path to achieve sustainable development.This paper uses my country’s provincial panel data from 2016 to 2019 to study the impact mechanism of R&D investment on green technology innovation,and introduces the level of digitization,using the panel threshold model to discuss its role in the impact mechanism of R&D investment on green technology innovation.The study found that when the level of digitalization in a region is low,increasing R&D investment does not necessarily improve the ability of green technology innovation;when the level of digitalization is relatively high,R&D investment has a positive role in promoting green technology innovation.Therefore,it is necessary to improve policies to encourage enterprises to increase investment in research and development;at the same time,it is necessary to promote the coordinated development of digital foundation,digital investment,digital literacy,digital economy and digital application,and promote the deep integration of digitalization and green technology innovation. 展开更多
关键词 green technology innovation R&D investment digital level panel model
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Advancements in Photovoltaic Panel Fault Detection Techniques
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作者 Junyao Zheng 《Journal of Materials Science and Chemical Engineering》 2024年第6期1-11,共11页
This paper examines the progression and advancements in fault detection techniques for photovoltaic (PV) panels, a target for optimizing the efficiency and longevity of solar energy systems. As the adoption of PV tech... This paper examines the progression and advancements in fault detection techniques for photovoltaic (PV) panels, a target for optimizing the efficiency and longevity of solar energy systems. As the adoption of PV technology grows, the need for effective fault detection strategies becomes increasingly paramount to maximize energy output and minimize operational downtimes of solar power systems. These approaches include the use of machine learning and deep learning methodologies to be able to detect the identified faults in PV technology. Here, we delve into how machine learning models, specifically kernel-based extreme learning machines and support vector machines, trained on current-voltage characteristic (I-V curve) data, provide information on fault identification. We explore deep learning approaches by taking models like EfficientNet-B0, which looks at infrared images of solar panels to detect subtle defects not visible to the human eye. We highlight the utilization of advanced image processing techniques and algorithms to exploit aerial imagery data, from Unmanned Aerial Vehicles (UAVs), for inspecting large solar installations. Some other techniques like DeepLabV3 , Feature Pyramid Networks (FPN), and U-Net will be detailed as such tools enable effective segmentation and anomaly detection in aerial panel images. Finally, we discuss implications of these technologies on labor costs, fault detection precision, and sustainability of PV installations. 展开更多
关键词 Photovoltaic panels Fault Detection Deep Learning Image Processing
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Composite Panels from the Combination of Rice Husk and Wood Chips with a Natural Resin Based on Tannins Reinforced with Sugar Cane Molasses Intended for Building Insulation: Physico-Mechanical and Thermal Properties
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作者 Paul Nestor Djomou Djonga Rosellyne Serewane Deramne +2 位作者 Gustave Assoualaye Ahmat Tom Tégawendé Justin Zaida 《Journal of Materials Science and Chemical Engineering》 2024年第2期19-30,共12页
The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips an... The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips and husks are materials which can have good thermal conductivity and therefore the combination of these precursors could make it possible to obtain panels with good insulating properties. With regard to environmental and climatic constraints, the composite panels formulated at various rates were tested and the physico-mechanical and thermal properties showed that it was essential to add a crosslinker in order to increase certain solicitation. an incorporation rate of 12% to 30% made it possible to obtain panels with low thermal conductivity, a low surface water absorption capacity and which gives the composite good thermal insulation and will find many applications in the construction and real estate sector. Finally, new solutions to improve the fire reaction of the insulation panels are tested which allows to identify suitable solutions for the developed composites. In view of the flame tests, the panels obtained are good and can effectively combat fire safety in public buildings. 展开更多
关键词 Composite panels Tannins Reinforced Sugar Cane Molasses Building Insulation Mechanical and Thermal Properties
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A Modified Principal Component Analysis Method for Honeycomb Sandwich Panel Debonding Recognition Based on Distributed Optical Fiber Sensing Signals
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作者 Shuai Chen Yinwei Ma +5 位作者 Zhongshu Wang Zongmei Xu Song Zhang Jianle Li Hao Xu Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2024年第2期125-141,共17页
The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scatt... The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scattering have been extensively deployed in structural health monitoring due to their advantages,such as lightweight and ease of embedding.However,identifying the precise location of damage from the optical fiber signals remains a critical challenge.In this paper,a novel approach which namely Modified Sliding Window Principal Component Analysis(MSWPCA)was proposed to facilitate automatic damage identification and localization via distributed optical fiber sensors.The proposed method is able to extract signal characteristics interfered by measurement noise to improve the accuracy of damage detection.Specifically,we applied the MSWPCA method to monitor and analyze the debonding propagation process in honeycomb sandwich panel structures.Our findings demonstrate that the training model exhibits high precision in detecting the location and size of honeycomb debonding,thereby facilitating reliable and efficient online assessment of the structural health state. 展开更多
关键词 Structural health monitoring distributed opticalfiber sensor damage identification honeycomb sandwich panel principal component analysis
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Comprehensive Examination of Solar Panel Design: A Focus on Thermal Dynamics
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作者 Kajal Sheth Dhvanil Patel 《Smart Grid and Renewable Energy》 2024年第1期15-33,共19页
In the 21st century, the deployment of ground-based Solar Photovoltaic (PV) Modules has seen exponential growth, driven by increasing demands for green, clean, and renewable energy sources. However, their usage is con... In the 21st century, the deployment of ground-based Solar Photovoltaic (PV) Modules has seen exponential growth, driven by increasing demands for green, clean, and renewable energy sources. However, their usage is constrained by certain limitations. Notably, the efficiency of solar PV modules on the ground peaks at a maximum of 25%, and there are concerns regarding their long-term reliability, with an expected lifespan of approximately 25 years without failures. This study focuses on analyzing the thermal efficiency of PV Modules. We have investigated the temperature profile of PV Modules under varying environmental conditions, such as air velocity and ambient temperature, utilizing Computational Fluid Dynamics (CFD). This analysis is crucial as the efficiency of PV Modules is significantly impacted by changes in the temperature differential relative to the environment. Furthermore, the study highlights the effect of airflow over solar panels on their temperature. It is found that a decrease in the temperature of the PV Module increases Open Circuit Voltage, underlining the importance of thermal management in optimizing solar panel performance. 展开更多
关键词 Solar Photovoltaic (PV) Modules Thermal Efficiency Analysis Open Circuit Voltage Computational Fluid Dynamics (CFD) Solar panel Temperature Profile
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A panel data model to predict airline passenger volume
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作者 Xiaoting Wang Junyu Cai Junyan Wang 《Digital Transportation and Safety》 2024年第2期46-52,共7页
Airline passenger volume is an important reference for the implementation of aviation capacity and route adjustment plans.This paper explores the determinants of airline passenger volume and proposes a comprehensive p... Airline passenger volume is an important reference for the implementation of aviation capacity and route adjustment plans.This paper explores the determinants of airline passenger volume and proposes a comprehensive panel data model for predicting volume.First,potential factors influencing airline passenger volume are analyzed from Geo-economic and service-related aspects.Second,the principal component analysis(PCA)is applied to identify key factors that impact the airline passenger volume of city pairs.Then the panel data model is estimated using 120 sets of data,which are a collection of observations for multiple subjects at multiple instances.Finally,the airline data from Chongqing to Shanghai,from 2003 to 2012,was used as a test case to verify the validity of the prediction model.Results show that railway and highway transportation assumed a certain proportion of passenger volumes,and total retail sales of consumer goods in the departure and arrival cities are significantly associated with airline passenger volume.According to the validity test results,the prediction accuracies of the model for 10 sets of data are all greater than 90%.The model performs better than a multivariate regression model,thus assisting airport operators decide which routes to adjust and which new routes to introduce. 展开更多
关键词 Airline passenger volume Traffic prediction panel data model Airline route decision Transportation engineering
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不同构型集成竹格栅夹芯板抗弯性能
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作者 王智丰 周李承 《北京林业大学学报》 北大核心 2025年第1期147-155,共9页
【目的】针对集成竹利用效率不高,使用形式较为单一的问题,探索其轻质、高效特性的先进结构形式,这对推动竹材在工程领域的应用方面具有重要意义。本研究旨在探究不同构型格栅芯体对集成竹格栅夹芯板弯曲性能的影响,选出不同格栅构型中... 【目的】针对集成竹利用效率不高,使用形式较为单一的问题,探索其轻质、高效特性的先进结构形式,这对推动竹材在工程领域的应用方面具有重要意义。本研究旨在探究不同构型格栅芯体对集成竹格栅夹芯板弯曲性能的影响,选出不同格栅构型中抗弯性能最优的结构,为其在实际工程的应用提供理论依据。【方法】以集成竹为原材料,通过嵌锁法分别设计加工3种具有不同构型(三角形格栅、方形格栅和Kagome形格栅)的集成竹格栅夹芯板。对不同格栅芯体的集成竹格栅夹芯板进行四点弯曲试验,探讨夹芯板结构的受弯性能,分析夹芯板结构在受弯荷载下的破坏机理、跨中挠度、抗弯刚度和极限承载力的变化规律,并对3种不同芯体集成竹格栅夹芯板结构的比强度和比刚度进行对比。同时,采用有限元方法建立集成竹格栅夹芯板四点弯曲试验模型,并进行数值模拟分析。【结果】3种不同构型格栅芯体的集成竹格栅夹芯板结构在受弯加载过程中均表现为剪切破坏。三角形集成竹格栅夹芯板的承载能力最好,三角形和Kagome形格栅极限承载力分别为38.7和27.5 kN,较极限承载力22.5 kN的方形格栅增加了71.9%和22.2%;同时三角形集成竹格栅夹芯板的比强度为133.5 kN·m/kg,较方形(94.6 kN·m/kg)和Kagome形(96.7 kN·m/kg)分别提高了41.2%和38.1%。有限元模型的模拟结果与试验结果较一致,能有效预测集成竹格栅夹芯板的弯曲性能。【结论】3种格栅构型中三角形集成竹夹芯板弯曲性能最优,能够更好地发挥集成竹轻质高强的性能优势。研究结果可为竹材在工程领域的应用提供一种高效的结构形式及理论依据。 展开更多
关键词 结构板材 有限元法 失效模式 弯曲强度 集成竹夹芯板 格栅构型
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供应链金融对中小企业R&D投资效率的影响:基于融资约束视角
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作者 胡海青 原敏倩 薛萌 《科技进步与对策》 北大核心 2025年第1期102-112,共11页
创新是中小企业保持竞争力、适应市场变化和实现可持续发展的关键。基于2016-2022年创业板中小企业相关数据,运用三阶段DEA分析、面板Tobit模型回归、二元Logistic回归等方法,探究供应链金融对中小企业R&D投资效率的影响。结果表明... 创新是中小企业保持竞争力、适应市场变化和实现可持续发展的关键。基于2016-2022年创业板中小企业相关数据,运用三阶段DEA分析、面板Tobit模型回归、二元Logistic回归等方法,探究供应链金融对中小企业R&D投资效率的影响。结果表明,供应链金融能够显著提高中小企业R&D投资效率,融资约束在二者间发挥遮掩效应。进一步分析发现,上述效应对供应链集中度较高的企业更为显著。结论可为发挥供应链金融筹资优势,促进供应链生态系统资源互补、信息共享的协同创新网络形成,进而支持中小企业创新活动提供理论支持。 展开更多
关键词 供应链金融 R&D投资效率 三阶段DEA 面板Tobit模型 遮掩效应
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虚拟仪器平台下旋转机械振动应用研究
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作者 曹慧 张锐英 +1 位作者 潘琦 方遒 《太原学院学报(自然科学版)》 2025年第1期63-70,共8页
利用LabVIEW软件图形化程序和可视化前面板,基于旋转机械结构和运动特点构建虚拟仪器仿真平台基本框架,设计了与真实仪器功能相当的旋转机械齿轮振动虚拟仿真研究平台。通过仿真验证,齿轮振动虚拟仿真平台能够有效采集振动信号,并对振... 利用LabVIEW软件图形化程序和可视化前面板,基于旋转机械结构和运动特点构建虚拟仪器仿真平台基本框架,设计了与真实仪器功能相当的旋转机械齿轮振动虚拟仿真研究平台。通过仿真验证,齿轮振动虚拟仿真平台能够有效采集振动信号,并对振动信号特征进行提取和分析,测试结果与旋转机械齿轮实际振动情况一致。开发的虚拟仿真平台达到了预期功能目标,为旋转机械关键部件振动检测和故障诊断提供了可视化技术支持,降低了旋转机械故障检测成本。 展开更多
关键词 齿轮振动 虚拟仪器 图形化程序 前面板 频谱分析
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基于改进YOLOv8的汽车门板紧固件检测算法
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作者 王晓辉 贾韫硕 郭丰娟 《计算机工程与设计》 北大核心 2025年第1期298-306,共9页
针对汽车门板紧固件在复杂场景下存在的检测准确度较低和实时性较差的问题,提出一种小目标改进算法YOLOv8-SOD(small object detection)。在主干网络引入SPD(space-to-depth)模块和自适应权重分配模块,在算法的颈部网络输出位置增加选... 针对汽车门板紧固件在复杂场景下存在的检测准确度较低和实时性较差的问题,提出一种小目标改进算法YOLOv8-SOD(small object detection)。在主干网络引入SPD(space-to-depth)模块和自适应权重分配模块,在算法的颈部网络输出位置增加选择性注意力模块,将CIOU损失函数替换为MPDIOU损失函数。实验结果表明,YOLOv8-SOD算法平均检测精度为99.1%,比模板匹配方法和YOLOv8算法分别提高了9.4%、2%,达到了工厂生产流水线的检测标准,具有实用价值。 展开更多
关键词 汽车门板紧固件检测 小目标 自适应权重分配 无参注意力 选择性注意力 损失函数 深度学习
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科学、技术的互动及其对经济发展的影响:基于panel data的实证研究 被引量:9
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作者 吴晓波 郑素丽 《科学学研究》 CSSCI 北大核心 2005年第6期740-745,共6页
进入知识经济社会,发展中国家的追赶和发展过程,更加依赖于科学、技术及其二者之间的相互作用。本文在前人研究的基础上,选择了中国30个省(市、自治区)的板面数据进行初步实证分析。研究发现,中国的基础科学研究、技术进步对经济发展存... 进入知识经济社会,发展中国家的追赶和发展过程,更加依赖于科学、技术及其二者之间的相互作用。本文在前人研究的基础上,选择了中国30个省(市、自治区)的板面数据进行初步实证分析。研究发现,中国的基础科学研究、技术进步对经济发展存在显著的促进作用,技术进步对经济发展的直接贡献要远大于基础科学研究的贡献;然而基础科学研究与技术进步之间的相互作用机制不甚理想,致使科学研究的作用未能很好发挥。最后在实证研究的基础上对科技和经济发展提供了若干对策建议,并提出进一步研究的建议。 展开更多
关键词 科学 技术 经济发展 panel DATA
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船舶兴波阻力计算的Panel方法及流场的可视化实现 被引量:5
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作者 李铁骊 王言英 林焰 《大连理工大学学报》 EI CAS CSCD 北大核心 1997年第1期87-90,共4页
采用Panel(面源)法,在微机上实现了船舶兴波阻力和可视化流场计算.在对一系列船舶进行数值计算后,将计算结果与采用Michel积分的兴波阻力计算结果以及实验测试结果进行比较,在中低Fr时。
关键词 船舶 兴波阻力 流场 可视化 panel
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基于Panel Data模型的中国土地市场发育区域差异及其对房价的影响 被引量:15
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作者 谭术魁 李雅楠 《中国土地科学》 CSSCI 北大核心 2013年第2期9-15,共7页
研究目的:分析中国土地市场发育的区域差异,以及这种差异对房价的影响。研究方法:面板数据模型。研究结果:(1)中国土地市场发育水平存在区域差异,区域内部的发育水平也不尽相同,东、中、西部的差异呈现先缩小后加大的趋势;(2)土地市场... 研究目的:分析中国土地市场发育的区域差异,以及这种差异对房价的影响。研究方法:面板数据模型。研究结果:(1)中国土地市场发育水平存在区域差异,区域内部的发育水平也不尽相同,东、中、西部的差异呈现先缩小后加大的趋势;(2)土地市场发育对房价的影响同样存在区域差异,东部、中部地区具有负向影响,且东部较中部显著,西部地区具有正向影响。研究结论:(1)提高土地市场发育水平可以促使房价达到合理水平;(2)在提高土地市场化水平的基础上不断完善市场经济环境,有利于这种作用的实现。 展开更多
关键词 土地经济 土地市场发育 房价 panel DATA模型
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基于Panel-data的区际产业转移粘性分析 被引量:19
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作者 张存菊 苗建军 《软科学》 CSSCI 北大核心 2010年第1期75-79,共5页
利用面板数据模型,以江苏省为例,对28个制造业的科技进步、产业集群、区域人力资本积累、沉没成本和资产专用性、劳动力跨区域流动、制度创新、政府阻力等因素对产业转移粘性的关系进行了实证研究,并依据各个因素的贡献率得出了跨区域... 利用面板数据模型,以江苏省为例,对28个制造业的科技进步、产业集群、区域人力资本积累、沉没成本和资产专用性、劳动力跨区域流动、制度创新、政府阻力等因素对产业转移粘性的关系进行了实证研究,并依据各个因素的贡献率得出了跨区域产业转移的初步结论。 展开更多
关键词 panel—data模型 产业转移 阻力因素
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中国人口政策的经济效应:OLG模型和Panel数据分析 被引量:6
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作者 吴信如 王静 王文婷 《华东师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2015年第4期93-99,170,共7页
基于世代交叠(OLG)模型,采用30个省份1983—2012年的面板数据,研究我国人口政策对经济增长及社会福利的影响,其模型分析与实证研究结果一致地表明:我国过去30多年实施的计划生育政策显著地推动了人均收入的增长,但也导致人口的老龄化趋... 基于世代交叠(OLG)模型,采用30个省份1983—2012年的面板数据,研究我国人口政策对经济增长及社会福利的影响,其模型分析与实证研究结果一致地表明:我国过去30多年实施的计划生育政策显著地推动了人均收入的增长,但也导致人口的老龄化趋势,带来潜在的养老资源不足和老年福利损失的问题。基于2010年人口普查数据进行的未来70年人口变动模拟显示,"单独二胎"政策作用微弱,不能改变人口结构老化的趋势,而全面"二胎化"政策将改善和稳定我国未来的人口结构,对稳定劳动力供给和养老、幼教等多方面的需求起关键作用,并由此助推人口、经济、社会的持续协调发展。因此,我国立即研究实施全面"二胎化"的人口生育政策是十分必要的。 展开更多
关键词 人口生育政策 经济效应 OLG模型 panel数据分析
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