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维生素ADE对华西牛繁殖性能的影响
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作者 夏春芳 周书甫 +1 位作者 王传军 高亮 《安徽农业科学》 2026年第5期70-72,81,共4页
[目的]探究维生素ADE复合注射液结合激素对华西牛母牛繁殖性能及卵巢功能的影响,为其应用提供理论依据。[方法]选取320头3~5胎次、体重(649.76±99.68)kg的健康经产华西牛母牛,随机分为4组:对照组(常规饲养)、激素组(生殖激素程序)... [目的]探究维生素ADE复合注射液结合激素对华西牛母牛繁殖性能及卵巢功能的影响,为其应用提供理论依据。[方法]选取320头3~5胎次、体重(649.76±99.68)kg的健康经产华西牛母牛,随机分为4组:对照组(常规饲养)、激素组(生殖激素程序)、试验Ⅰ组(激素程序+单次维生素ADE)和试验Ⅱ组(激素程序+3次维生素ADE),试验周期为450 d。[结果]试验Ⅱ组的产犊间隔显著短于对照组和激素组(P<0.05),分别减少25 d和13 d;受胎率达95.00%,较对照组、激素组和试验Ⅰ组分别提高11.25、5.00和3.75百分点;难产率降至1.32%,与其他3组相比降幅为1.42百分点~3.16百分点。同时,该组优势卵泡直径较对照组和激素组分别增大3.56 mm和1.65 mm(P<0.05),卵泡发育变异系数最低,黄体溶解率达95.00%,表明试验Ⅱ组的母牛繁殖性能与卵巢功能得到同步优化。[结论]经产华西牛母牛在激素处理基础上,于产后42 d、人工授精后2 h及产前60 d注射维生素ADE,可有效缩短产犊间隔、促进卵泡同步发育、提高受胎率并改善难产状况,有利于母牛的同期发情处理。 展开更多
关键词 维生素ade 华西牛 繁殖性能 卵巢功能
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Cascade explicit tube model predictive controller:application for a multi-robot system
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作者 Ehsan Soleimani Amirhossein Nikoofard Erfan Nejabat 《Control Theory and Technology》 2025年第2期237-252,共16页
In recent years,there has been a growing demand for more efficient and robust control strategies in cooperative multi-robot systems.This paper introduces the cascade explicit tube model predictive controller(CET-MPC),... In recent years,there has been a growing demand for more efficient and robust control strategies in cooperative multi-robot systems.This paper introduces the cascade explicit tube model predictive controller(CET-MPC),a control architecture designed specifically for distributed aerial robot systems.By integrating an explicit model predictive controller(MPC)with a tube MPC,our approach significantly reduces online computational demands while enhancing robustness against disturbances such as wind and measurement noise,as well as uncertainties in inertia parameters.Further,we incorporate a cascade controller to minimize steady-state errors and improve system performance dynamically.The results of this assessment provide valuable insights into the effectiveness and reliability of the CET-MPC approach under realistic operating conditions.The simulation results of flight scenarios for multi-agent quadrotors demonstrate the controller’s stability and accurate tracking of the desired path.By addressing the complexities of quadrotors’six degrees of freedom,this controller serves as a versatile solution applicable to a wide range of multi-robot systems with varying degrees of freedom,demonstrating its adaptability and scalability beyond the quadrotor domain. 展开更多
关键词 explicit model predictive control(MPC) Tube MPC Cascade controller QUADROTOR Multi-agent system Distributed formation control
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Exact Computer Modeling of Photovoltaic Sources with Lambert-W Explicit Solvers for Real-Time Emulation and Controller Verification
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作者 Abdulaziz Almalaq Ambe Harrison +2 位作者 Ibrahim Alsaleh Abdullah Alassaf Mashari Alangari 《Computer Modeling in Engineering & Sciences》 2026年第1期873-891,共19页
We present a computer-modeling framework for photovoltaic(PV)source emulation that preserves the exact single-diode physics while enabling iteration-free,real-time evaluation.We derive two closed-form explicit solvers... We present a computer-modeling framework for photovoltaic(PV)source emulation that preserves the exact single-diode physics while enabling iteration-free,real-time evaluation.We derive two closed-form explicit solvers based on the Lambert W function:a voltage-driven V-Lambert solver for high-fidelity I–V computation and a resistance-driven R-Lambert solver designed for seamless integration in a closed-loop PV emulator.Unlike Taylor-linearized explicit models,our proposed formulation retains the exponential nonlinearity of the PV equations.It employs a numerically stable analytical evaluation that eliminates the need for lookup tables and root-finding,all while maintaining limited computational costs and a small memory footprint.The R-Lambert model is integrated into a buck-converter emulator equipped with a discrete PI regulator,which generates current references directly from sensed operating points,thus supporting hardware-constrained implementation.Comprehensive numerical experiments conducted on six commercial modules from various technologies(mono,poly,and multicrystalline)demonstrate significant accuracy improvements under the IEC EN 50530 near-MPP criterion:the V-Lambert solver reduces the±10%Vmpp band error by up to 61 times compared to an explicit-model baseline.Dynamic simulations under varying irradiance,temperature,and load conditions achieve millisecond-scale settling with accurate trajectory tracking.Additionally,processor-in-the-loop experimental validation on an embedded microcontroller supports the simulation results.By unifying exact analytical modeling with embedded realization,this work advances computer modeling for PV emulation,MPPT benchmarking,and controller verification in integrated renewable energy systems. 展开更多
关键词 Photovoltaic emulators(PVE) explicit PV model(EPVM) IEC EN 50530 Lambert function maximum power point(MPP) PVE integration processor-in-the loop
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Implicit and Explicit Analysis of the Response of Blast Loaded Reinforced Concrete Slabs
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作者 Kamel S. Kandil Mouhamad T. Nemir +1 位作者 Ehab A. Ellobody Ramy I. Shahin 《World Journal of Engineering and Technology》 2014年第3期211-221,共11页
Implicit and explicit analyses were examined with experimental work done by Razaqpur et al. In the experiment work, two 1000 × 1000 × 70 mm reinforced concrete slabs were constructed. The slabs were subjecte... Implicit and explicit analyses were examined with experimental work done by Razaqpur et al. In the experiment work, two 1000 × 1000 × 70 mm reinforced concrete slabs were constructed. The slabs were subjected to blast loads generated by the detonation of either 22.4 kg or 33.4 kg of ANFO located at a 3.0 m standoff. Blast wave characteristics, including incident and reflected pressures and reflected impulses were measured. The slabs were modeled by implicit and explicit analysis to study their behavior under blast load to compare their predicted and observed behavior. The post-blast damage and mode of failure of each slab were observed. It was concluded that explicit analysis provides better modeling than implicit analysis. 展开更多
关键词 IMPLICIT ANALYSIS explicit ANALYSIS Strain Rate BLAST Load Ansys LS-DYNA Scaled DISTANCE
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Long burn arc powered explicit guidance algorithm for Earth-to-Moon missions 被引量:1
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作者 Haifeng HU Liang YAN +2 位作者 Cong WANG Jinlin WANG Pengjie XIANG 《Chinese Journal of Aeronautics》 2025年第12期337-347,共11页
Earth-to-Moon missions with low thrust-to-weight ratios present unique challenges for exoatmospheric guidance,and the existing algorithms are ineffective for the unprecedentedly long burn arcs and high orbital eccentr... Earth-to-Moon missions with low thrust-to-weight ratios present unique challenges for exoatmospheric guidance,and the existing algorithms are ineffective for the unprecedentedly long burn arcs and high orbital eccentricities.To address these challenges,a Long Burn Arc Powered Explicit Guidance(LBA-PEG)algorithm is developed and compared with the existing algorithms.In the proposed LBA-PEG algorithm,a fully numerical thrust prediction method is developed to accurately predict the highly nonlinear thrust effects over long burn arcs.Moreover,a real-time Newton correction method is proposed to correct the orbit injection point,remedying the position-velocity coupling induced by high orbital eccentricities.The comparison between the proposed algorithm and the existing algorithm shows that the proposed algorithm surpasses the existing ones by significantly enhancing fuel efficiency and improving tolerance to thrust decrease.The proposed LBA-PEG algorithm can adapt to a 65%thrust decrease,which is 12%–22%larger than that of the existing algorithms,and it can still reliably converge and complete the guidance mission even when the length of the burn arc exceeds 90°.The proposed LBA-PEG highlights the algorithm's adaptability for long burn arc missions,especially in critical scenarios such as manned Earth-to-Moon missions. 展开更多
关键词 Large eccentricity Launch vehicle Long burn arc Numerical guidance method Powered explicit guidance
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阿尔茨海默病Aβ免疫治疗患者的综合管理 被引量:1
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作者 赵春梅 许贤瑞 +1 位作者 李晓聪 张庆 《西安交通大学学报(医学版)》 北大核心 2026年第1期39-47,共9页
靶向β-淀粉样蛋白(β-amyloid,Aβ)的单克隆抗体药物仑卡奈单抗(Lecanemab)和多奈单抗(Donanemab)开启了阿尔茨海默病(Alzheimer’s disease,AD)疾病修饰治疗(disease-modifying therapy,DMT)时代。然而,AD是一个复杂的疾病过程,接受... 靶向β-淀粉样蛋白(β-amyloid,Aβ)的单克隆抗体药物仑卡奈单抗(Lecanemab)和多奈单抗(Donanemab)开启了阿尔茨海默病(Alzheimer’s disease,AD)疾病修饰治疗(disease-modifying therapy,DMT)时代。然而,AD是一个复杂的疾病过程,接受单克隆抗体免疫治疗的AD患者需要综合管理。本文系统综述了Aβ免疫治疗患者的综合管理模式,包括一般治疗、改善认知功能、控制精神行为症状、非药物治疗、多学科协作等方面,旨在为临床医师提供基于循证医学的综合管理策略。 展开更多
关键词 阿尔茨海默病(AD) β-淀粉样蛋白(Aβ) Aβ免疫治疗 综合管理
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补充维生素ADE对奶牛生产影响的对比实验 被引量:1
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作者 张园 《中国动物保健》 2025年第1期200-202,共3页
维生素ADE均为脂溶性维生素,是参与动物机体代谢的重要营养物质。笔者通过在奶牛养殖和生产几个阶段中补充维生素ADE,对比出奶牛在繁殖、产奶等重要生产环节所产生的影响,为畜牧兽医和奶牛饲养者提供参考。
关键词 奶牛 补充维生素ade 对比实验
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Progressive explicit formulae for root-finding problems based on reparameterization
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作者 WANG Hui QIAN Cheng CHEN Xiao-diao 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第4期833-852,共20页
This paper presents an explicit formula based on reparameterization technique for progressively computing a simple root of a smooth function,which may have wide applications in robotics,geomagnetic navigation,geometri... This paper presents an explicit formula based on reparameterization technique for progressively computing a simple root of a smooth function,which may have wide applications in robotics,geomagnetic navigation,geometric processing and computer graphics.Comparing with Newton-like method,it can achieve convergence rate 2 by adding one more functional evaluation,improve the computational stability and ensure the convergence,and also obtain higher convergence rate and higher efficiency index.Compared with clipping methods for polynomials,it doesn't need to bound the polynomials,directly bound the roots and can also work well for non-polynomial functions with much higher computational efficiency.Comparing with previous progressive methods,it achieves a much higher computational efficiency and is extended to solve bivariate equation system.Numerical examples show its much better performance on approximation error,computational efficiency and computational stability. 展开更多
关键词 root-nding re-parameterization-based method clipping method numerical iterative method convergence order non-linear equation system progressive explicit formulae
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Observer-Based Robust Explicit Model Predictive Control for Path Following of Autonomous Electric Vehicles with Communication Delay
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作者 Jing Zhao Renbin Li +3 位作者 Mingze Lv Wenfeng Li Zhengchao Xie Pak Kin Wong 《Chinese Journal of Mechanical Engineering》 2025年第5期224-238,共15页
The existing research on the path following of the autonomous electric vehicle(AEV)mainly focuses on the path planning and the kinematic control.However,the dynamic control with the state observation and the communica... The existing research on the path following of the autonomous electric vehicle(AEV)mainly focuses on the path planning and the kinematic control.However,the dynamic control with the state observation and the communication delay is usually ignored,so the path following performance of the AEV cannot be ensured.This article studies the observer-based path following control strategy for the AEV with the communication delay via a robust explicit model predictive control approach.Firstly,a projected interval unscented Kalman filter is proposed to observe the vehicle sideslip angle and yaw rate.The observer considers the state constraints during the observation process,and the robustness of the observer is also considered.Secondly,an explicit model predictive control is designed to reduce the computational complexity.Thirdly,considering the efficiency of the information transmission,the influence of the communication delay is considered when designing the observer-based path following control strategy.Finally,the numerical simulation and the hardware-in-the-loop test are conducted to examine the effectiveness and practicability of the proposed strategy. 展开更多
关键词 Path following explicit model predictive control Communication delay Projected interval unscented Kalman filter
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阿尔茨海默病Aβ免疫治疗的临床获益
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作者 刘洁 刘佩杰 +4 位作者 高玲 党亮君 魏珊 屈秋民 王瑾 《西安交通大学学报(医学版)》 北大核心 2026年第1期18-24,共7页
β淀粉样蛋白(β-amyloid,Aβ)在脑内沉积是阿尔茨海默病(Alzheimer’s disease,AD)发病的关键环节,应用抗Aβ单克隆抗体清除Aβ是AD最重要的疾病修饰治疗。仑卡奈单抗和多奈单抗是目前批准上市的两种抗Aβ抗体。本文通过系统回顾两药... β淀粉样蛋白(β-amyloid,Aβ)在脑内沉积是阿尔茨海默病(Alzheimer’s disease,AD)发病的关键环节,应用抗Aβ单克隆抗体清除Aβ是AD最重要的疾病修饰治疗。仑卡奈单抗和多奈单抗是目前批准上市的两种抗Aβ抗体。本文通过系统回顾两药的关键Ⅲ期临床试验,尤其关注治疗过程中淀粉样蛋白PET-CT及脑脊液或血浆生物标志物的改变以及疗效评估,总结不同患者临床疗效的异质性及其可能的影响因素,同时结合中国西北地区真实世界研究的初步随访数据,系统综述了靶向Aβ的单克隆抗体作为AD的疾病修饰疗法的临床获益,并提出应采用“有意义的获益”(meaningful benefit)这一新概念进行评估,强调AD疾病修饰疗法治疗的目标并非短期症状改善,而是长期治疗的累积效应,即治疗时间越长,延缓认知和功能衰退的效果越明显,从而推迟患者进入疾病更严重阶段的时间。这为临床医师治疗决策、疗效评估和患者管理提供重要依据。 展开更多
关键词 阿尔茨海默病(AD) β淀粉样蛋白(Aβ) 免疫治疗 淀粉样蛋白单克隆抗体 临床获益
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淀粉样蛋白相关影像学异常的识别与管理
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作者 张玉洁 孟新玲 《西安交通大学学报(医学版)》 北大核心 2026年第1期48-54,共7页
淀粉样蛋白相关影像学异常(amyloid-related imaging abnormalities,ARIA)是磁共振成像(magnetic resonance imaging,MRI)观察到的颅内信号异常,是阿尔茨海默病(Alzheimer’s disease,AD)抗β-淀粉样蛋白(β-amyloid,Aβ)单克隆抗体治... 淀粉样蛋白相关影像学异常(amyloid-related imaging abnormalities,ARIA)是磁共振成像(magnetic resonance imaging,MRI)观察到的颅内信号异常,是阿尔茨海默病(Alzheimer’s disease,AD)抗β-淀粉样蛋白(β-amyloid,Aβ)单克隆抗体治疗的重要不良事件,严重者可危及患者生命。ARIA主要包括淀粉样蛋白相关影像学异常-水肿/渗出型(amyloid-related imaging abnormalities-edema/effusion,ARIA-E)和淀粉样蛋白相关影像学异常-微出血/含铁血黄素沉积型(amyloid-related imaging abnormalities-hemorrhage/hemosiderin,ARIA-H)2种类型。ARIA的病理生理机制涉及淀粉样蛋白沉积引发的血管源性水肿和脑微出血。随着抗Aβ单克隆抗体在中国获批使用,临床医师面对ARIA的可能性将增加,早期识别和规范管理ARIA可平衡抗Aβ治疗的疗效与安全性,为患者提供更优的个体化治疗策略;用药期间及时识别与判断ARIA的严重程度对临床决策具有重要意义。 展开更多
关键词 阿尔茨海默病(AD) 抗Aβ单克隆抗体 淀粉样蛋白相关影像学异常(ARIA) 磁共振成像(MRI) 风险管理
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Impact of Building Materials for the Facade on Energy Consumption and Carbon Emissions (Case Study of Residential Buildings in Tehran)
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作者 Amir Sina Darabi Mehdi Ravanshadnia 《Energy Engineering》 2025年第9期3753-3792,共40页
Although currently,a large part of the existing buildings is considered inefficient in terms of energy,the ability to save energy consumption up to 80%has been proven in residential and commercial buildings.Also,carbo... Although currently,a large part of the existing buildings is considered inefficient in terms of energy,the ability to save energy consumption up to 80%has been proven in residential and commercial buildings.Also,carbon dioxide is one of the most important greenhouse gases contributing to climate change and is responsible for 60%of global warming.The facade of the building,as the main intermediary between the interior and exterior spaces,plays a significant role in adjusting the weather conditions and providing thermal comfort to the residents.In this research,715 different scenarios were defined with the combination of various types of construction materials,and the effect of each of these scenarios on the process of energy loss from the surface of the external walls of the building during the operation period was determined.In the end,these scenarios were compared during a one-year operation period,and the amount of energy consumption in each of these scenarios was calculated.Also,bymeasuring the amount of carbon emissions in buildings during the operation period and before that,let’s look at practical methods to reduce the effects of the construction industry on the environment.By comparing the research findings,it can be seen that the ranking of each scenario in terms of total energy consumption is not necessarily the same as the ranking of energy consumption for gas consumption or electricity consumption for the same scenario.That is,choosing the optimal scenario depends on the type of energy consumed in the building.Finally,we determined the scenarios with the lowest and highest amounts of embodied and operational carbon.In the end,we obtained the latent carbon compensation period for each scenario.This article can help designers and construction engineers optimize the energy consumption of buildings by deciding on the right materials. 展开更多
关键词 Design builder software carbon emissions embedded carbon operational carbon building façade materials energy consumption
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A New Dawn Rising:New Options for Windows,Facades&Walls with Vacuum Glass and Other Integrated Building Innovations
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作者 Helmut Hohenstein 《Journal of Civil Engineering and Architecture》 2025年第3期137-147,共11页
This year summarizes the experience of industrialization of vacuum glazing in the past twenty years.A series of technical difficulties have been solved to start the first global mass production of high-quality vacuum ... This year summarizes the experience of industrialization of vacuum glazing in the past twenty years.A series of technical difficulties have been solved to start the first global mass production of high-quality vacuum glass.High quality means high performance and long life which are interrelated.A mass production line must be able to achieve these two requirements if it is to produce vacuum glazing products that can be accepted by the society.With a U-value of 0.4 W/m²·K based on Low-E(low emissivity)with an emissivity of 0.03 the door is wide open for further solutions.Time,gradually to improve costs,maximizes output and develops innovative solutions of advanced window and façade systems combining complete new features like smart glasses,intelligent lamella systems in hybrid VG-IG solutions changing the building world towards“Energy plus Houses”.Market demand will rapidly increase with completely new options.Cost saving means to balance additional advantages for savings against system costs of window or façade elements.Due to promotion of energy saving and emission reduction,both,subjective and objective conditions for industrialization of vacuum glasses are perfect;the building world is waiting for it,since long.There is a lot to investigate and to gain for business success. 展开更多
关键词 Vacuum glass energy saving advanced window and façade systems industrial production Energy+Houses
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连续体机器人显式时间归零动态运动控制
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作者 刘宜成 程靖 +2 位作者 严文 梁斌 陈章 《电光与控制》 北大核心 2026年第3期32-38,45,共8页
针对柔性材料构成的连续体机器人在轨迹跟踪控制中难以快速收敛的问题,提出了一种基于显式时间的归零动态模型。首先,基于显式时间理论设计了归零动态方程,确保误差监视函数能够在显式时间内快速收敛至零。随后,基于此模型,针对连续体... 针对柔性材料构成的连续体机器人在轨迹跟踪控制中难以快速收敛的问题,提出了一种基于显式时间的归零动态模型。首先,基于显式时间理论设计了归零动态方程,确保误差监视函数能够在显式时间内快速收敛至零。随后,基于此模型,针对连续体机器人建模复杂且难以设计控制器的难题,提出了一种通用的雅可比矩阵状态估计器和逆运动学求解器,构建了适用于连续体机器人显式时间运动控制的收敛方法,并通过数值仿真验证了所提方法的可行性。最后,设计搭建了连续体机器人实验平台并验证了所提方法的有效性。 展开更多
关键词 连续体机器人 显式时间 归零动态学 状态估计 逆运动学
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一种伪造注意图驱动的多任务深伪视频检测模型
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作者 刘鹏宇 郑添阳 董敏 《电子与信息学报》 北大核心 2026年第1期346-358,共13页
目前高质量深度伪造视频检测方法大多基于隐式注意力机制的监督二分类模型。虽然该类模型能够通过自学习,判别伪造痕迹,鉴别异常区域,但在面对未经学习的伪造技术时,对伪造区域的敏感性降低,泛化性不足。基于此,该文提出一种伪造注意图... 目前高质量深度伪造视频检测方法大多基于隐式注意力机制的监督二分类模型。虽然该类模型能够通过自学习,判别伪造痕迹,鉴别异常区域,但在面对未经学习的伪造技术时,对伪造区域的敏感性降低,泛化性不足。基于此,该文提出一种伪造注意图驱动的多任务深伪视频检测模型(F-BiFPN-MTLNet)。首先,设计了一种融合伪造注意图的新型加权双向特征金字塔网络(F-BiFPN),通过伪造注意图监督低层和高层特征图的融合过程,在减少信息冗余的同时,增强模型对高质量伪造区域的敏感性。然后,定义了一种基于显式注意力机制的多任务学习网络(MTLNet)。一方面,该网络在原有基于监督二分类器的单任务模型的基础上,结合基于可学习掩码的注意策略与增强自一致性的注意策略,实现多任务加权判别,提高模型检测的可靠性;另一方面,引入显式注意力机制,通过生成的伪造位置标签对特征图进行监督,显式地指导模型聚焦于容易产生伪影的敏感区域,提高模型的泛化能力。实验结果表明,该文构建的F-BiFPN-MTLNet模型在多个基准测试中均表现出了较好性能,在曲线下面积(AUC)和平均精度(AP)等指标上取得了显著的提升。 展开更多
关键词 深度伪造 深度学习 显式注意力 多任务学习
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共生理念下揉捻机组模块化设计方法研究
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作者 周红宇 薛爽 +2 位作者 戚得众 刘明勇 白浪 《数字农业与智能农机》 2026年第3期1-7,共7页
为探寻装备设计领域产品系统共生策略,促进“人-机-环境”的多元生产系统和谐共生,以某款揉捻机组设计优化为例,提出一种共生理念下装备模块化设计策略。采用实地考察和桌面研究相结合的方法开展揉捻机组的需求调研,基于共生理念视角重... 为探寻装备设计领域产品系统共生策略,促进“人-机-环境”的多元生产系统和谐共生,以某款揉捻机组设计优化为例,提出一种共生理念下装备模块化设计策略。采用实地考察和桌面研究相结合的方法开展揉捻机组的需求调研,基于共生理念视角重构揉捻机组的需求库;利用AD模型中的“Z字映射”和独立公理原则,实现从需求域到功能域再到物理域的转化;通过共生理念的零部件关联度评价模型对设计参数相关性进行量化分析,并代入装备DSM矩阵中,利用系统聚类解得模块划分方案,最终经设计优化完成揉捻机组的设计。研究表明,该方法可有效促进生产系统的内部和谐,为装备领域理论与设计相结合提供研究参考。 展开更多
关键词 共生理念 模块化设计 揉捻机组 AD模型
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电催化塑料废物升级回收研究进展
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作者 李琛 刘金成 +1 位作者 辛颖 倪双阳 《中国塑料》 北大核心 2026年第3期119-124,共6页
系统综述了近年来电催化技术在不同类型废塑料(聚酯类、聚烯烃类及其他塑料)转化中的应用进展,重点探讨了催化剂设计策略(电子结构调控、界面工程、表面形貌优化及晶相工程)对反应性能的影响。最后,针对规模化应用的技术瓶颈,提出利用... 系统综述了近年来电催化技术在不同类型废塑料(聚酯类、聚烯烃类及其他塑料)转化中的应用进展,重点探讨了催化剂设计策略(电子结构调控、界面工程、表面形貌优化及晶相工程)对反应性能的影响。最后,针对规模化应用的技术瓶颈,提出利用理论计算指导高效催化剂研发、开发高效分离技术、设计工业级反应器等未来发展方向,为电催化废塑料回收技术的工业化与循环经济转型提供理论支撑。 展开更多
关键词 废塑料 升级回收 电催化 高值化学品
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基于扰动补偿的林果园轮式机器人ENMPC轨迹跟踪方法
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作者 沈跃 王辉 +3 位作者 张亚飞 何思伟 杨开奇 刘慧 《农业工程学报》 北大核心 2026年第3期26-35,共10页
针对自主林果园轮式机器人在复杂作业环境中易受外部扰动与模型参数不确定性影响,导致轨迹跟踪精度下降的问题,该研究提出一种基于非线性扰动观测器(nonlinear disturbance observer,NDOB)的预测精度增强显式非线性模型预测控制(explici... 针对自主林果园轮式机器人在复杂作业环境中易受外部扰动与模型参数不确定性影响,导致轨迹跟踪精度下降的问题,该研究提出一种基于非线性扰动观测器(nonlinear disturbance observer,NDOB)的预测精度增强显式非线性模型预测控制(explicit nonlinear model predictive control,ENMPC)算法。首先,在理想运动学模型中引入农业地形常见的车轮滑移与转向滑移扰动,构建扩展运动学模型。在假设所有外部扰动均可测的前提下,通过泰勒级数展开近似滚动时域内的跟踪误差,推导ENMPC的显式解析解,无需实时求解优化问题。然后设计NDOB实时估计并补偿外部扰动与参数不确定性,并严格证明了所提复合控制器的稳定性。与传统的前馈补偿策略不同,该算法将扰动估计直接集成到输出预测模型中,从而实现零稳态偏差控制。仿真结果表明,该算法能够有效抑制多类扰动信号,显著提升轨迹跟踪控制精度与鲁棒性。草地工况试验表明,与标准NMPC算法相比,所提出的NDOB-ENMPC算法在横、纵向的最大绝对偏差分别降低了39.42%和49.01%,平均绝对偏差分别降低了29.45%和44.01%,平均求解时间减少了97.47%。与前馈补偿NMPC算法相比,所提出的NDOB-ENMPC算法在横、纵向的最大绝对偏差分别降低了17.86%和37.64%,平均绝对偏差分别降低了16.41%和20.59%,平均求解时间减少了97.57%。该算法可满足林果园轮式机器人在复杂农业环境下轨迹跟踪控制的实时性与精度需求,为实现最优控制策略在农业机器人的低成本部署提供解决方案。 展开更多
关键词 扰动观测器 林果园轮式机器人 显式模型预测控制 轨迹跟踪 最优控制
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改进学习自动机的分簇式航空自组网时隙分配方法
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作者 李冬霞 高毅 刘海涛 《空军工程大学学报》 北大核心 2026年第1期48-57,共10页
针对现有的航空自组网资源分配方案在跨洋场景应用中存在控制开销大、时隙利用率低等问题,基于分簇式航空自组网提出一种改进学习自动机算法的时隙分配(ILASA)方案。首先,给出分簇式航空自组网络模型;其次,设计了时隙帧结构,改进了学习... 针对现有的航空自组网资源分配方案在跨洋场景应用中存在控制开销大、时隙利用率低等问题,基于分簇式航空自组网提出一种改进学习自动机算法的时隙分配(ILASA)方案。首先,给出分簇式航空自组网络模型;其次,设计了时隙帧结构,改进了学习自动机算法的时隙分配模式并优化了奖惩机制中的概率更新方法,通过增加时隙预约机制来解决学习自动机算法存在的概率选择偏差问题;最后,基于OMNeT++平台搭建网络模型进行仿真。结果表明:所提方案能减少由于控制信息造成的资源开销,有效降低网络平均端到端时延,提高网络吞吐量及数据包投递率。 展开更多
关键词 航空自组网 分簇 时隙分配 学习自动机
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融合Phyphox的声速测量实验改进与教学探究
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作者 陈廷芳 胡耀阳 +3 位作者 潘宇婷 冯振华 夏冉 刘金梅 《物理教学探讨》 2026年第3期57-62,共6页
超声法测声速实验是大学物理实验教学的核心内容,传统实验常用示波器观测测量,但示波器存在波形稳定性差、驻波非理想化及能量衰减不可视等局限,制约学生对驻波理论的理解。为此,结合驻波共振法,提出Phyphox软件与ESP32单片机结合的实... 超声法测声速实验是大学物理实验教学的核心内容,传统实验常用示波器观测测量,但示波器存在波形稳定性差、驻波非理想化及能量衰减不可视等局限,制约学生对驻波理论的理解。为此,结合驻波共振法,提出Phyphox软件与ESP32单片机结合的实验方案,构建智能化声速测量系统。硬件上,ESP32单片机集成高精度ADS1120模数转换模块,实现超声波信号稳定采集并降低噪声;软件上,通过Thonny开发嵌入式程序,借助Phyphox完成数据动态可视化采集;理论上,突破传统理想模型,建立含声波衰减系数与界面反射率的驻波方程,揭示声压幅值随传播距离的增加而衰减的规律。实验表明:与传统示波器相比,Phyphox-ESP32系统降低了误差,引入ADS1120后精度显著提升;系统通过实时波形迁移与能量衰减可视化,直观呈现驻波动态形成机制,解决传统实验观测缺陷与交互性不足的问题。为大学物理实验数字化提供低成本、高精度技术路径,同时也为中学物理实验教学提供了新思路,具有重要的应用价值。 展开更多
关键词 超声波声速测量 Phyphox ESP32单片机 ADS1120 驻波共振法 误差分析
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