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Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： Yang Yang guanxin Yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

Dynamic response analysis under atmospheric disturbances for helicopters based on elastic blades

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Chinese Journal of Aeronautics 2017年第2期30卷 628-637页

作者： Tong Liu Yuting Dai guanxin hong Linpeng Wang School of Aeronautic Science and Engineering Beihang University Beijing 100083 China

A flight dynamics model based on elastic blades for helicopters is *** shape analysis is used to describe the rotating elastic blades for the purpose of reducing the elastic degrees of freedom for *** analytical result is employed to predict the rotor forces and *** equilibrium equation of the flight dynamics model is then constructed for the elastic motion for blades and the rigid motion for other *** nonlinear equation is further simplified,and the gradient descent algorithm is adopted to implement the trim *** trim analysis shows that the effect of blade elasticity on the accuracy of rotor forces and moments is apparent at high speed,and the proposed method presents good accuracy for trim *** timedomain response is realized by a combination of the Newmark method and the adaptive RungeKutta *** helicopter control responses of collective pitch show that the response accuracy of the model at a yaw-and-pitch attitude is ***,the influence of blade elasticity on the helicopter dynamic response in low-altitude wind shear is *** increase in blade elasticity reduces the oscillation amplitude of the yaw angle and the vertical speed by more than 70%.Compared with a rigid blade,an elastic blade reduces the vibration frequency of the angular velocity and results in a fast return of the helicopter to its stable flight.

关键词： Dynamic model Elastic Helicopter Time domain analysis Trimming Wind shear

Synthetic Strategies of Carbon Nanobelts and Beyond

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Chemical Research in Chinese Universities 2024年第4期40卷 627-631页

作者： LI Yanbang SHANG Wansong REN Yu ZHANG Xi-Sha LI Cheng ZHANG guanxin ZHANG Deqing Beijing National Laboratory for Molecular Science CAS Key Laboratory for Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing100190P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

Carbon nanobelts(CNBs)with aesthetically appealing molecular structures and outstanding physical properties have attracted more and more attentions from the scientific community due to their potential applications in synthetic materials,host-guest chemistry,optoelectronics,and so *** synthesis of CNBs at different stages was overviewed and some representative breakthroughs and advances in synthetic strategies were highlighted and *** key issue for the synthesis of CNBs is how to construct curved structures with high strain *** not only proposed a few unconventional CNBs as the promising target molecules,but also pointed out the bottom-up synthesis of conjugated tubular segments of carbon nanotubes sharing similar properties as carbon nanotubes is the next focus in this emerging area.

关键词： Carbon nanobelt Strain energy Carbon nanoring Single-walled carbon nanotube Bottom-up synthesis

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运输机尾流场的小型空投物资下落轨迹仿真

哈尔滨工程大学学报 2019年第2期40卷 273-278页

作者：高静洪冠新北京航空航天大学航空科学与工程学院北京100191

为了研究运输机的下洗尾流场对小型物资空投轨迹的影响规律,应用基于位势流理论的涡格法对全机尾流场的速度分布进行数值求解,并建立伞货一体的刚性动力学模型,仿真分析了小型空投物资在载机尾流场影响下的下落轨迹。研究表明,尾流场会... 详细信息

为了研究运输机的下洗尾流场对小型物资空投轨迹的影响规律,应用基于位势流理论的涡格法对全机尾流场的速度分布进行数值求解,并建立伞货一体的刚性动力学模型,仿真分析了小型空投物资在载机尾流场影响下的下落轨迹。研究表明,尾流场会使空投物资下落轨迹向飞机飞行方向整体偏移,并且随着载机平飞速度增加,尾流场对空投物资下落轨迹的偏移量反而减小。

关键词：空投运输机尾流场涡格法动力学建模动力学仿真下落轨迹下洗尾流场

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入流模型对直升机配平及动态响应的影响

北京航空航天大学学报 1999年第5期25卷 539-542页

作者：杨超洪冠新北京航空航天大学飞行器设计与应用力学系

以常规单旋翼带尾桨直升机为对象，讨论均匀与非均匀入流模型对直升机飞行数值仿真的影响．以ＰｉｔｔＰｅｔｅｒｓ的动力入流模型为基础，讨论均匀与非均匀入流模型对直升机配平的影响，并分别采用非均匀静态入流、均匀与非均匀动... 详细信息

以常规单旋翼带尾桨直升机为对象，讨论均匀与非均匀入流模型对直升机飞行数值仿真的影响．以ＰｉｔｔＰｅｔｅｒｓ的动力入流模型为基础，讨论均匀与非均匀入流模型对直升机配平的影响，并分别采用非均匀静态入流、均匀与非均匀动力入流模型，分析直升机在低速、中速和高速前飞时对驾驶员操纵输入动态响应数值仿真的精度及影响程度，为不同目的飞行数值仿真中入流模型的选取提供有益的参考．

关键词：直升机飞行力学入流动力学动态响应配平

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风切变场中直升机前飞状态动态响应

北京航空航天大学学报 2005年第5期31卷 524-528页

作者：洪冠新庞健北京航空航天大学航空科学与工程学院北京100083

为解决复杂风切变场中直升机运动的数值仿真,把握非线性直升机模型在风场中的响应特性,建立了一维、二维的风切变模型,采用直升机非线性飞行动力学模型,考虑直升机的控制系统,用四阶龙格-库塔法数值仿真直升机在风场中的前飞运动.对水... 详细信息

为解决复杂风切变场中直升机运动的数值仿真,把握非线性直升机模型在风场中的响应特性,建立了一维、二维的风切变模型,采用直升机非线性飞行动力学模型,考虑直升机的控制系统,用四阶龙格-库塔法数值仿真直升机在风场中的前飞运动.对水平风和铅垂风的各个梯度场对响应的影响进行比较.结果表明,水平风和铅垂风的各个梯度场对响应的影响是不同的,此研究中二维空间的组合梯度场构成更为危险的飞行环境;在不同的情况下其作用是不可忽略的,尤其注意在低空飞行状态下对直升机飞行性能的影响.也进一步说明此数值仿真法对非线性直升机模型在复杂风场中响应研究实用有效.

关键词：直升机非线性风切变动态响应

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基于地形高程数据的复杂地形风场建模方法

北京航空航天大学学报 2014年第3期40卷 360-364页

作者：唐矗洪冠新北京航空航天大学航空科学与工程学院北京100191

提出了一种以地形高程数据为基础,进行三维复杂地形建模及其风场分布求解的数值仿真方法.该方法利用曲面样条插值技术建立复杂地形的三维数字模型,并将地形曲面离散为若干个涡环网格,结合位势流理论与地面边界条件计算得到复杂地形影响... 详细信息

提出了一种以地形高程数据为基础,进行三维复杂地形建模及其风场分布求解的数值仿真方法.该方法利用曲面样条插值技术建立复杂地形的三维数字模型,并将地形曲面离散为若干个涡环网格,结合位势流理论与地面边界条件计算得到复杂地形影响下的三维风场.数值计算结果显示,相比基于球绕流理论的工程模拟方法,该方法可对复杂地形做出更为真实的描述,并给出更为合理的风场分布形式.同时该方法建模过程简单,便于实际操作,适于飞机飞行性能评估或飞行模拟器环境建模的工程应用.

关键词：复杂地形风场建模等高线曲面样条函数涡环网格

Simulation of the Dynamic Environment of Carrier Aircraft Approach and Landing

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Simulation of the Dynamic Environment of Carrier Aircraft Ap...

2013年中国智能自动化学术会议

作者： Xianjian Chen Gang Liu guanxin hong School of Aeronautic Science and Engineering Beihang University State Key Laboratory of Virtual Reality Technology and Systems Beihang University National Laboratory for Aeronautics and Astronautics Beihang University

Simulation of marine environment is very important for the system of carrier aircraft approach and *** effect of environment on landing of carrier aircraft has been *** designs an environment scenario generator from dynamic characteristics of environment which as a simulation node accesses to the federal system of carrier aircraft *** can increase the reusability and operability of the environmental *** realization methods of fog,cloud and illumination which affect the visibility of the environment of carrier-based aircraft landing have been discussed from the basic *** it provides a basis for the visualization of the environmental data.

关键词： Marine environment Dynamic characteristics Environment scenario generator Realization methods

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雷达信号误差对舰载机全自动着舰控制的影响

北京航空航天大学学报 2017年第6期43卷 1247-1253页

作者：杨宝钧刘刚洪冠新北京航空航天大学航空科学与工程学院北京100083

基于常规舰载机使用的全自动着舰系统(ACLS),以及现役的作为主要导引方式的雷达导引着舰,分析了雷达导引过程中的信号误差对着舰的影响。从全自动着舰系统的组成和作用出发,建立完整的着舰仿真系统与环境,加入雷达信号测量数值、时间延... 详细信息

基于常规舰载机使用的全自动着舰系统(ACLS),以及现役的作为主要导引方式的雷达导引着舰,分析了雷达导引过程中的信号误差对着舰的影响。从全自动着舰系统的组成和作用出发,建立完整的着舰仿真系统与环境,加入雷达信号测量数值、时间延迟和噪声杂波干扰3种不同类型的误差,以仿真误差存在时的着舰状况。通过计算着舰成功率,及其随误差量值的绝对值增大而减小的特点,验证了结果的正确性。该方法定量分析雷达信号误差的影响,既有助于着舰理论的研究,也对工程设计和应用具有指导意义。

关键词：舰载机全自动着舰雷达导引雷达信号误差着舰成功率