Working Park即办公室综合生活方式,是以绿色生态、节能环保、便捷高效为主旨的新型规划模式;它强调以人为本,使公共利益最大化,使用者身心健康最大化,将建筑、公共空间、园林、休闲设施等有机结合,营造出时尚灵动的办公与生活空间;本...Working Park即办公室综合生活方式,是以绿色生态、节能环保、便捷高效为主旨的新型规划模式;它强调以人为本,使公共利益最大化,使用者身心健康最大化,将建筑、公共空间、园林、休闲设施等有机结合,营造出时尚灵动的办公与生活空间;本文以中交汇通横琴广场的主塔楼办公室内部分为例,解析working park理念在超高层综合体建筑的室内应用成果。展开更多
Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmann...Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmanned surface vehicles(USVs).We assume that each agent suffers from by the mixed constraints on its velocity,control input and Euler angle.Solving the MDFT problem implies that 1)The virtual state of each USV is determined in the earth coordinate by expanding its 2D work space to the 3D space.展开更多
Element stiffness equation is very important in structural analysis, and directly influences the accuracy of the results. At present, derivation method of element stiffness equation is relatively mature under ambient ...Element stiffness equation is very important in structural analysis, and directly influences the accuracy of the results. At present, derivation method of element stiffness equation is relatively mature under ambient temperature, and the elastic phrase of material stress-strain curve is generally adopted as physical equation in derivation. However, the material stress-strain relationship is very complicated at elevated temperature, and its form is not unique, which brings great difficulty to the derivation of element stiffness equation. Referring to the derivation method of element stiffness equation at ambient temperature, by using the continuous function of stress-strain-temperature at elevated temperature, and based on the principle of virtual work, the stiffness equation of space beam element and the formulas of stiffness matrix are derived in this paper, which provide basis for finite element analysis on structures at elevated temperature.展开更多
The thermodynamic system consists of the entropy flow and entropy product.This paper is to define the entropy flow and to apply it to determinig the minimal work in air-exhausting processes.It is found that the minimu...The thermodynamic system consists of the entropy flow and entropy product.This paper is to define the entropy flow and to apply it to determinig the minimal work in air-exhausting processes.It is found that the minimum work depends only on the pressure at the negative-pressure space.展开更多
多功能雷达(Multi Function Radar,MFR)通过波形捷变与波束自适应调度实现多任务协同,这给雷达工作模式识别带来了诸多挑战。现有识别方法依赖脉冲序列局部时域特征,难以有效解析不同工作模式的生成机理,面对脉冲丢失、脉内参数相近等...多功能雷达(Multi Function Radar,MFR)通过波形捷变与波束自适应调度实现多任务协同,这给雷达工作模式识别带来了诸多挑战。现有识别方法依赖脉冲序列局部时域特征,难以有效解析不同工作模式的生成机理,面对脉冲丢失、脉内参数相近等复杂情况,识别性能急剧下降。考虑到多功能雷达波束扫描过程对脉冲组序列幅值信息的影响,提出一种基于空时联合图卷积网络的多功能雷达工作模式识别方法。该网络模型首先通过引入动态规整模块量化相邻波位信号的辐射特性相似度,构造具有物理可解释性的空域邻接矩阵;然后将一维脉冲组序列映射为二维图结构,融合脉冲频率、信号幅度等节点特征,形成空时联合表征;最后,设计分层图卷积核,通过多层信息传递机制,提取深层空时特征,完成雷达工作模式识别。对比实验表明,在脉冲丢失等非理想情况下所提方法的平均识别率仍能达到93.38%,具有更好的泛化性和鲁棒性。展开更多
文摘研究受限空间内过头作业人员疲劳特征,以避免疲劳累积和降低事故风险。设计了典型受限空间内过头作业试验,测量20名被试在不同受限空间高度(120 cm、140 cm)和不同工作面(侧面、顶面、正面)下的表面肌电(Surface Electromyogram,sEMG)信号和心率变异性(Heart Rate Variability,HRV)信号,记录主观疲劳评分,并对数据进行分析。结果表明:受限空间内过头作业疲劳累积明显;右肩膀和右前臂主观疲劳评分最高;左上斜方肌、右上斜方肌、右中三角肌、右冈上肌、右冈下肌和右肱桡肌中位频率(Median Frequency,MF)下降显著,右中三角肌MF下降幅度最大;相邻RR间期均值(RR mean)降低,低频成分(Low Frequency,LF)和低频高频比值(Ratio of Low Frequency to High Frequency,LF/HF)均上升;与120 cm高度相比,140 cm高度下全身及5个身体部位主观疲劳评分更高,6个肌群MF下降斜率更大,RR mean下降幅度以及LF、LF/HF上升幅度更大;工作面对主观疲劳评分、各肌群MF及HRV指标影响不显著,但正面工作面除右肱桡肌外5个肌群均疲劳累积显著,侧面和顶面工作面右上斜方肌、右中三角肌和右冈上肌3个肌群疲劳累积显著。
基金supported in part by the National Natural Science Foundation of China(62073301,62373162,62473349,U24A20268,62233007)the Shenzhen Science and Technology Program(JCYJ20240813114007010).
文摘Dear Editor,This letter investigates the problem of multi-dimension formation tracking(MDFT)for the cross-domain unmanned systems,including several interconnected agents,namely,unmanned aerial vehicles(UAVs)and unmanned surface vehicles(USVs).We assume that each agent suffers from by the mixed constraints on its velocity,control input and Euler angle.Solving the MDFT problem implies that 1)The virtual state of each USV is determined in the earth coordinate by expanding its 2D work space to the 3D space.
基金the National Natural Science Foundation of China(No.50578093)
文摘Element stiffness equation is very important in structural analysis, and directly influences the accuracy of the results. At present, derivation method of element stiffness equation is relatively mature under ambient temperature, and the elastic phrase of material stress-strain curve is generally adopted as physical equation in derivation. However, the material stress-strain relationship is very complicated at elevated temperature, and its form is not unique, which brings great difficulty to the derivation of element stiffness equation. Referring to the derivation method of element stiffness equation at ambient temperature, by using the continuous function of stress-strain-temperature at elevated temperature, and based on the principle of virtual work, the stiffness equation of space beam element and the formulas of stiffness matrix are derived in this paper, which provide basis for finite element analysis on structures at elevated temperature.
文摘The thermodynamic system consists of the entropy flow and entropy product.This paper is to define the entropy flow and to apply it to determinig the minimal work in air-exhausting processes.It is found that the minimum work depends only on the pressure at the negative-pressure space.
文摘多功能雷达(Multi Function Radar,MFR)通过波形捷变与波束自适应调度实现多任务协同,这给雷达工作模式识别带来了诸多挑战。现有识别方法依赖脉冲序列局部时域特征,难以有效解析不同工作模式的生成机理,面对脉冲丢失、脉内参数相近等复杂情况,识别性能急剧下降。考虑到多功能雷达波束扫描过程对脉冲组序列幅值信息的影响,提出一种基于空时联合图卷积网络的多功能雷达工作模式识别方法。该网络模型首先通过引入动态规整模块量化相邻波位信号的辐射特性相似度,构造具有物理可解释性的空域邻接矩阵;然后将一维脉冲组序列映射为二维图结构,融合脉冲频率、信号幅度等节点特征,形成空时联合表征;最后,设计分层图卷积核,通过多层信息传递机制,提取深层空时特征,完成雷达工作模式识别。对比实验表明,在脉冲丢失等非理想情况下所提方法的平均识别率仍能达到93.38%,具有更好的泛化性和鲁棒性。
