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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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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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阿尔茨海默病Aβ免疫治疗患者的综合管理
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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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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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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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显性教学和隐性教学对话题组织型话语标记习得的影响
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作者 杨黎黎 《汉语学习》 北大核心 2026年第1期85-94,共10页
显性教学和隐性教学不应该被理解为二元对立,实际上它们不同程度地参与到所有的学习情境中并相互影响。在显性和隐性的连续统一体中,设计了显性语法组、输入洪流组、增强型输入洪流组三种不同的干预模式。话题组织型话语标记在输入中出... 显性教学和隐性教学不应该被理解为二元对立,实际上它们不同程度地参与到所有的学习情境中并相互影响。在显性和隐性的连续统一体中,设计了显性语法组、输入洪流组、增强型输入洪流组三种不同的干预模式。话题组织型话语标记在输入中出现频率较高,但其词汇意义较虚,语法特征在输入中不易被注意到因而具有低显著性,较为容易成为内隐知识。在课堂时间不变的情况下,隐性教学有效性关键在于输入频率;增强型输入洪流有效地解决了话语标记的低显著性问题。足够高频的输入可以让隐性学习者注意到输入中的这些语法特征较弱、语用特征较强的话语标记;在视觉上和听觉上得到加强的输入更能让学习者顺利产出那些功能单一、位置固定的话语标记。 展开更多
关键词 显性教学 隐性教学 输入洪流 话语标记 例频率
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海上压裂船在波浪中的水动力响应数值模拟研究
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作者 袁文奎 徐志海 +3 位作者 范高曌 郭晓强 王新根 孟令韬 《西南石油大学学报(自然科学版)》 北大核心 2026年第1期116-126,共11页
基于三维势流理论分析中国海上首台压裂船的水动力性能,研究其在不同浪向角、波浪谱峰周期和波高下船舶的运动响应规律。借助AQWA软件对系泊压裂船的频域响应进行分析计算,计算出船舶的运动幅值响应算子、附加质量与辐射阻尼,将数值分... 基于三维势流理论分析中国海上首台压裂船的水动力性能,研究其在不同浪向角、波浪谱峰周期和波高下船舶的运动响应规律。借助AQWA软件对系泊压裂船的频域响应进行分析计算,计算出船舶的运动幅值响应算子、附加质量与辐射阻尼,将数值分析结果与课题组所开展的耐波性实验数据开展比对验证,评估模型的有效性与准确性。然后依据频域分析的结果对压裂船的时域系泊问题进行分析,得到在不同波浪参数下的压裂船时域的系泊响应。研究表明,波浪周期对船舶横荡附加质量的影响小,纵荡方向附加质量呈现先减小后增大再减小的趋势,垂荡附加质量则与其相反。纵摇和艏摇方向的附加质量随波浪谱峰周期的增大呈现出先减小后增大再减小的变化趋势,而对于横摇方向,附加质量变化不大。此外,压裂船在不同波浪谱峰周期作用下,各自由度辐射阻尼均表现出先增强后减弱的特性。船体横摇角有义值在浪向角从0°增至180°过程中,呈现先增大后减小的趋势,最大值位于90°方位;纵摇角的变化趋势则呈先减后增加,180°时纵摇角有义值最大。随着波浪谱峰周期的增加,横摇和垂荡有义值呈现出增加的趋势,而纵摇角有义值呈先上升后下降的趋势。波高的增加使得船舶的横摇、纵摇及垂荡方向的有义值都上升。研究成果可为大型船舶在波浪条件下的运动响应分析的方法和技术应用提供一定的理论依据和基础。 展开更多
关键词 势流理论 水动力 辐射阻尼 附加质量 频域 时域
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数字经济全口径增加值核算方法研究
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作者 任雪 秦瑶 +1 位作者 周先东 薛健 《当代经济科学》 北大核心 2026年第1期1-16,共16页
随着数字经济统计工作进入实践阶段,数字经济核心产业和融合产业增加值核算面临的若干复杂问题逐步凸显,制约了中国政府部门数字经济统计工作发展。在全面梳理总结国内外数字经济统计核算研究现状的基础上,以《数字经济及其核心产业统... 随着数字经济统计工作进入实践阶段,数字经济核心产业和融合产业增加值核算面临的若干复杂问题逐步凸显,制约了中国政府部门数字经济统计工作发展。在全面梳理总结国内外数字经济统计核算研究现状的基础上,以《数字经济及其核心产业统计分类(2021)》为指导,重点讨论数字经济统计内涵,优化数字经济增加值核算范围,深入研究中国数字经济全口径增加值统计核算方法,在数据来源、核算方法和统计制度方面进行探索创新,提出可操作、可复制和可推广的一揽子数字经济全口径增加值核算方案。以重庆市为例,对数字经济全口径增加值核算方案进行试算验证。结果表明,该核算方案在核算方法思路、核算基础数据依赖、核算系数专项调查方案等方面具有科学性和实用性,能够为全国及各地区统计系统提供可复制、可参考的核算框架。据此为数字经济增加值核算提供新的思路和方法,为相关部门制定和完善中国数字经济统计核算制度的政策建议提供有益参考。 展开更多
关键词 数字经济统计 核心产业 融合产业 投入产出表 增加值 核算范围 核算方法
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隐性知识与中国自主知识体系构建
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作者 刘学斌 《北京社会科学》 北大核心 2026年第1期57-68,共12页
隐性知识不同于显性知识,是难以察觉、表达的知识,常与惯习、偏好、实践相联系。隐性知识普遍存在于教育、管理等各个领域和从个人到文明的各个层级,并且具有方法论意义,是解析知识活动、知识现象的必备视角。从隐性知识角度可以发现,... 隐性知识不同于显性知识,是难以察觉、表达的知识,常与惯习、偏好、实践相联系。隐性知识普遍存在于教育、管理等各个领域和从个人到文明的各个层级,并且具有方法论意义,是解析知识活动、知识现象的必备视角。从隐性知识角度可以发现,隐性知识与中国自主知识体系存在着密切关联。中华优秀传统文化和现代化历程中生成、积累的隐性知识是中国自主知识体系的重要知识来源,中国自主知识体系包含着大量自主性的隐性知识,在隐性知识方面的成功是中国自主知识体系构建成功的重要标志之一。在构建中国自主知识体系的过程中,应注重从中国已有隐性知识资源和当前现代化实践中获取隐性知识,进而充实中国自主知识体系,也应有意识地遵循隐性知识本身的运动规律,通过隐性知识的外显化、显性知识的内化、隐性知识的传递等途径,借助口述史等技术方法,加强知识生产、知识系统化工作。 展开更多
关键词 中国自主知识体系 隐性知识 显性知识 中华优秀传统文化 中国式现代化
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高职学生劳动素养增值评价路径探析
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作者 韩继红 林娟 《宁波职业技术大学学报》 2026年第2期81-85,共5页
通过将劳动教育与专业教育、技能培养相融合,从成长增值的角度,构建学生劳动素养增值评价机制,有利于提高劳动素养评价内容的科学性和针对性,更好地发挥评价的诊断改进功能。劳动素养增值评价,即将学生劳动素养提升过程融入专业综合素... 通过将劳动教育与专业教育、技能培养相融合,从成长增值的角度,构建学生劳动素养增值评价机制,有利于提高劳动素养评价内容的科学性和针对性,更好地发挥评价的诊断改进功能。劳动素养增值评价,即将学生劳动素养提升过程融入专业综合素养提升之中,通过高职院校三年的连续周期性评价,考察学生劳动素养增值情况,并根据评价结果进行个体、班级、专业、学校和省域画像,将数据进行可视化呈现,便于学生自我诊改、教师指导、学校及教育主管部门评估劳动教育成效。 展开更多
关键词 劳动素养 增值评价 劳动教育
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