China's low-carbon competitiveness and its effect decomposition from the perspective of wellbeing performance of ecological input

From the perspective of wellbeing performance of ecological input,this paper constructs a low-carbon competitiveness evaluation model with wellbeing performance of carbon emissions as the measurement standard,and uses the LMDI factor decomposition method to decompose the total effect of low-carbon competitiveness changes into technology effect and service effect.And then it conducts positive analysis and comparison of the low-carbon competitiveness and its effect contribution of G20 countries from1990 to 2018.The results are as follows:Firstly,in 2018,the UK,France,Argentina,Brazil,and Germany had higher low-carbon competitiveness.From 1990 to 2018,the low-carbon competitiveness of the UK,Turkey,Germany,Italy,and Brazil increase rapidly.Secondly,from 1990 to 2018,the total effect of low-carbon competitiveness of G20 member states was all positive,that is to say,the overall wellbeing performance of carbon emissions increased,technology effect and service effect are positive in 17 countries and negative in 2 countries respectively.Thirdly,China's low-carbon competitiveness is low,lacking static and dynamic advantages,although the technology effect is the highest,but the service effect is the lowest,resulting in a low total effect,which indicates that the wellbeing performance of economic growth is the main bottleneck of China's low-carbon development.Finally,the policy recommendations for China's future low-carbon transition and sustainable development are put forward.

Prescribed Performance Control of One-DOF Link Manipulator With Uncertainties and Input Saturation Constraint

In this paper, we mainly address the position control problem for one-degree of freedom(DOF) link manipulator despite uncertainties and the input saturation via the backstepping technique, active disturbance rejection control(ADRC) as well as predefined tracking performance functions. The extended state observer(ESO) is employed to compensate uncertain dynamics and disturbances, and it does not rely on the accurate model of systems. The tracking differentiator(TD) is utilized to substitute the derivative of the virtual control signals, and the explosion of complexity caused by repeated differentiations of nonlinear functions is removed. The auxiliary system is used to deal with the control input limitation, and the tracking accuracy and speed are improved by predefined tracking performance functions.With the help of the input-to-state stability(ISS) and Lyapunov stability theories, it is proven that the tracking error can be gradually converged into arbitrarily small neighborhood of the origin, and the tracking error is adjusted by suitable choice of control parameters. The simulation results are presented for the verification of the theoretical claims.

Event-based performance guaranteed tracking control for constrained nonlinear system via adaptive dynamic programming method

An optimal tracking control problem for a class of nonlinear systems with guaranteed performance and asymmetric input constraints is discussed in this paper.The control policy is implemented by adaptive dynamic programming(ADP)algorithm under two event-based triggering mechanisms.It is often challenging to design an optimal control law due to the system deviation caused by asymmetric input constraints.First,a prescribed performance control technique is employed to guarantee the tracking errors within predetermined boundaries.Subsequently,considering the asymmetric input constraints,a discounted non-quadratic cost function is introduced.Moreover,in order to reduce controller updates,an event-triggered control law is developed for ADP algorithm.After that,to further simplify the complexity of controller design,this work is extended to a self-triggered case for relaxing the need for continuous signal monitoring by hardware devices.By employing the Lyapunov method,the uniform ultimate boundedness of all signals is proved to be guaranteed.Finally,a simulation example on a mass–spring–damper system subject to asymmetric input constraints is provided to validate the effectiveness of the proposed control scheme.

PERFORMANCE ANALYSIS OF AN INPUT-BUFFERED ATM SWITCHING FABRIC WITH INDEPENDENT WINDOW-ACCESS SCHEME

In this paper, an Independent Window-Access(IWA) scheme is proposed, and the performance of an input-buffered ATM switching fabric with the IWA scheme is analysed by means of a probability generating function approach, the closed formulas of the average cell delay and the maximum throughput are given, and results show that the IWA scheme makes the switching fabric have better performances than traditional window-access scheme. The computer simulation results are in good agreement with these analytical results.

PERFORMANCE ANALYSIS OF ATM SWITCH FABRIC WITH COMBINED-INPUT/OUTPUT BUFFERING

This paper analyses the performance of the ATM switch fabric with Combined-Input/ Output Buffering(C-IOB) under two different service principles for the cells at the head of line (HOL) positions of input buffers: First Come First Service (FCFS)/Random Service(RS) for the set of HOL cells addressed to a given output port with different/same "age" (the waiting time at the HOL position) and Pure Random Service(PRS) for all HOL cells addressed to a given output port regardless of their "ages" while the Queue Loss (QL) transfer scheme is adopted for interaction between input and output buffers in the ATM switch fabric. The results obtained show that the C-IOB ATM switch fabric with PRS service policy and the QL transfer scheme is better than other buffering ATM switch fabrics.

A Comparison and Performance of Different Optical Switching Architectures

Optical Packet Switching (OPS) and transmission networks based on Wavelength Division Multiplexing (WDM) have been increasingly deployed in the Internet infrastructure over the last decade in order to meet the huge increasing demand for bandwidth. Several different technologies have been developed for optical packet switching such as space switches, broadcast-and-select, input buffered switches and output buffered switches. These architectures vary based on several parameters such as the way of optical buffering, the placement of optical buffers, the way of solving the external blocking inherited from switching technologies in general and the components used to implement the WDM. This study surveys most of the exiting optical packet switching architectures. A simulation-based comparison of input buffered and output buffered architectures is presented. The performance analysis of the selected two architectures is derived using simulation program and compared at different scenarios. We found that the output buffered architectures give better performance than input buffered architectures. The simulation results show that the-broadcast-and-select architecture is attractive in terms that it has lees number of components compared to other switches.

具有输入时滞和预设性能的非线性系统有限时间动态面控制

针对一类具有输入时滞和动态不确定性的非严格反馈非线性系统的跟踪问题,提出一种新的基于预设性能的有限时间自适应跟踪控制方案.利用Pade逼近和辅助中间变量将有时滞系统转化为无时滞系统,采用由一阶辅助系统生成的动态信号处理未建模动态,引入双曲正切函数实现预设性能跟踪控制,并给出基于动态面控制方法的稳定性分析.在MATLAB环境中,以具有未建模动态和输入时滞的二阶非线性系统为例,对所提出的控制策略进行数值仿真.结果表明:所提出的控制方案能够避免现有有限时间控制所出现的虚拟控制求导奇异性问题,所有信号有限时间有界,跟踪误差收敛到预设的时变区间,可见控制算法切实有效.

具有输入输出约束的无人直升机预设性能安全跟踪控制

针对无人直升机姿态与高度系统存在未知外部干扰、输入饱和、姿态与高度约束等问题,本文提出一种具有输入输出约束的预设性能安全跟踪控制方法.首先,针对无人直升机的姿态与高度约束,通过设计一类边界保护算法,构建了新的安全期望跟踪信号.为了保证系统对于安全期望跟踪信号的跟踪性能,将预设性能函数与边界保护算法进行结合,并对跟踪误差进行转换.针对系统的输入饱和现象,使用Sigmoid函数进行逼近;同时,针对饱和函数的逼近误差与未知外部干扰构成的复合干扰,采用参数自适应方法对其上界进行逼近.然后,结合反步控制方法设计了安全跟踪控制器,并通过Lyapunov稳定性理论证明了闭环系统所有信号的收敛性,保证了无人直升机的安全跟踪性能.最终,通过数值仿真验证了所提控制方法的有效性.

输入受限乘波体飞行器无估计预设性能控制

针对输入受限的乘波体飞行器跟踪控制问题,提出了一种无估计的预设性能控制方法。首先,针对可能发生的执行器饱和问题,设计了一种新型抗饱和补偿系统。然后,利用补偿系统状态构造新的预设性能转换误差,基于预设性能控制与反演控制的方法,为速度子系统与高度子系统设计了无需估计的低复杂度控制器。该设计方法的优越性在于无需状态估计与神经逼近,显著降低了控制的复杂度与计算量。基于Lyapunov稳定理论证明了所有转换误差与跟踪误差最终一致有界。最后,通过数值仿真验证了所提方法的有效性。

基于输入饱和的欠驱动水面舰艇预定义时间跟踪控制

[目的]为解决欠驱动水面舰艇(USV)在模型不确定性、强耦合特性和控制器输入饱和情况下的轨迹跟踪问题,提出基于输入饱和的USV预定义时间跟踪控制方法。[方法]针对USV模型具有非零对角项和强耦合特性问题,引入坐标变换,将系统模型转变为斜对角形式;将预定义时间性能函数与障碍Lyapunov函数(BLF)结合,保证瞬态和稳态的跟踪性能;利用自组织神经网络(SSNN)降低未知外部环境扰动和复杂的连续未知非线性项以及输入饱和产生的影响,以保证控制系统的跟踪精度,并且在线调整优化SSNN的神经元数目,减少控制系统的计算负担。[结果]基于Lyapunov稳定性理论,证明了闭环系统在预定义时间内是有界稳定的,跟踪误差始终保持在约束范围内。[结论]仿真结果表明,所提控制策略是有效的,其具有良好的跟踪性能。

一种控制输入约束下的不确定离散系统非脆弱保性能控制器设计

【目的】针对考虑扰动及摄动情况下的控制输入约束的不确定离散系统,提出了非脆弱保性能的控制方法。【方法】首先,以最小化目标函数为性能指标、控制输入饱和范围为约束条件,从而推导出约束状态下的非脆弱保性能控制律。其次,使用李雅普诺夫方程来构造非线性矩阵不等式。再次,结合Schur补定理和布谷鸟群智能优化算法对不等式进行求解,得到控制输入约束下的非脆弱保性能控制律的参数。最后,通过Quanser三自由度陀螺仪平台进行试验验证。【结果】试验结果表明,本研究所提出方法的稳态误差浮动不超过0.07、跟踪误差不超过0.15。【结论】该方法在面对扰动及摄动情况时具有更高的鲁棒性,对提升三自由度陀螺仪的稳定性及控制精度具有重要意义。

Anti-saturation fault-tolerant adaptive torsional vibration control with fixed-time prescribed performance for rolling mill main drive system

An anti-saturation fault-tolerant adaptive torsional vibration control method with fixed-time prescribed performance for the rolling mill main drive system(RMMDS)was investigated,which is affected by control input saturation,actuator faults,sensor measurement errors,and parameter perturbations.First,we gave a continuously differentiable saturation function to approximate the control input saturation characteristic of the RMMDS,translating the saturation characteristic into the matched uncertainty and unknown time-varying gain in the system.Then,an RMMDS mathematical model with unmatched uncertainty and unknown time-varying gain was developed,taking into account the presence of control input saturation,actuator faults,sensor measurement errors,and parameter perturbations.Based on the established mathematical model,an error transformation model of the roll speed tracking was constructed by the equivalent error transformation method.According to the error transformation model,a barrier Lyapunov function and a novel adaptive controller were studied to ensure that the roll speed tracking error always evolves inside a fixed-time asymmetric constraint.Finally,numerical simulations were performed in Matlab/Simulink to verify the effectiveness and superiority of the proposed control method in suppressing the RMMDS torsional vibration.

区域创新投入与创新绩效的关系及地方政府科技创新支持下的最优转化区间

为明确区域创新投入与创新绩效间的作用机制研究两个问题,一是总体上区域创新投入是否对创新绩效有正向影响,二是不同的地方政府科技创新支持水平是否会影响区域创新投入与创新绩效之间的关系、是否存在最优的地方政府科技创新支持水平区间,基于我国31个省份2010—2021年的面板数据,分别采用面板回归和门槛模型进行实证研究。研究结果表明,区域创新投入对创新绩效有正向影响,且存在东部、中部、西部的区域异质性特征,中部相关系数最高,西部最低;不同的地方政府科技创新支持水平下,区域创新投入与创新绩效之间存在显著的双门槛效应,当地方政府科技创新支持处于中等水平时,区域创新投入向创新绩效转化效率最高,但目前我国31个省份地方政府科技创新普遍处于高水平。因此提出政策建议,一方面要持续坚持区域创新投入并考虑区域异质性特征;另一方面在经济复苏压力下地方政府应优化调整创新资源配置,从以前的关注区域创新投入数额转向关注创新投入向创新绩效转化效率。

城市轨道交通网络系统效率评价指标改进

为提高城市轨道交通网络系统效率评价指标的可比性和完备性,引入有效行程速度和有效客流密度的概念,改进了网络系统效率评价指标,并以重庆市中心城区2017年和2019年运营的城市轨道交通线网为例验证了改进后评价指标的科学性和可操作性。研究表明:既有评价指标由于显著受到线网服务范围的影响,且未体现网络的投入产出效率,无法直接作为网络结构优化的目标函数;改进后的系统效率评价指标能够综合反映剔除线网服务范围影响后的网络结构性能和投入产出效率,且存在理论上的最优值;平衡网络中节点换乘时间和路段行程时间,并适度加密城市核心区域的轨道交通线路和站点,是持续提升网络系统效率的2个重要手段。

具有规定性能的多智能体动态事件触发编队控制

针对多智能体系统编队控制过程中面临的性能约束、输入饱和、通信资源受限等问题,研究一类具有规定性能的高阶非仿射多智能体系统编队控制问题,提出一种有限时间动态事件触发编队控制策略。首先利用反步法设计控制律,并引入微分跟踪技术解决“计算爆炸”问题,有效避免对复杂虚拟控制律的求导过程;其次采用模糊逻辑系统估计系统内部的不确定性,通过设计性能函数和饱和补偿系统使得多智能体满足规定瞬态性能并防止输入饱和所带来的影响;随后为了解决通信资源受限的问题,构造一个具有动态阈值的自适应事件触发协议,有效减少控制器与执行器之间的通信量;最后利用李雅普诺夫稳定性理论分析闭环系统的稳定性,保证编队误差将渐近收敛至0且系统中所有信号均有界。采用含有1个领导者和5个跟随者的多智能体模型进行仿真验证,结果表明,在该有限时间动态事件触发编队控制策略下,多智能体系统最终形成以领导者为圆心、跟随者都在圆上的编队队形,且编队误差在规定的范围内演化。

基于投入-产出视角口岸实验室科研创新绩效评价指标体系构建

实验室作为海关科技创新的重要组成部分,在技术引领、培养科研人才等方面具有重要作用。本文根据口岸卫生检疫实验室的特点,以科学公正、统筹兼顾、激励约束为原则,构建了口岸卫生检疫实验室科研创新绩效评价指标体系。主要围绕管理水平、人才队伍、设施设备条件、创新能力、把关服务作用、信息收集、交流与合作、可持续发展能力等方面评估卫生检疫实验室科研创新绩效。在指标体系的基础上提出合理的建议,对科学评价海关实验室科研创新效果、促进海关实验室建设发展、加强口岸实验室能力建设具有重要意义。

High Throughput Scheduling Algorithms for Input Queued Packet Switches

The high-performance computing paradigm needs high-speed switching fabrics to meet the heavy traffic generated by their applications.These switching fabrics are efficiently driven by the deployed scheduling algorithms.In this paper,we proposed two scheduling algorithms for input queued switches whose operations are based on ranking procedures.At first,we proposed a Simple 2-Bit(S2B)scheme which uses binary ranking procedure and queue size for scheduling the packets.Here,the Virtual Output Queue(VOQ)set with maximum number of empty queues receives higher rank than other VOQ’s.Through simulation,we showed S2B has better throughput performance than Highest Ranking First(HRF)arbitration under uniform,and non-uniform traffic patterns.To further improve the throughput-delay performance,an Enhanced 2-Bit(E2B)approach is proposed.This approach adopts an integer representation for rank,which is the number of empty queues in a VOQ set.The simulation result shows E2B outperforms S2B and HRF scheduling algorithms with maximum throughput-delay performance.Furthermore,the algorithms are simulated under hotspot traffic and E2B proves to be more efficient.

A DEA MODEL FOR IDENTIFYING CRITICAL INPUT-OUTPUT PERFORMANCE MEASURES

In this paper,the authors propose a new model for identifying the critical input-output combinations for each DMU.A real-world application case of 21 international tourist hotels(ITHs) is used to illustrate the proposed approach.

“投入—产出”视角下省级重点实验室创新绩效研究——以福建省为例

目前省级重点实验室建设评价的研究工作大多停留在科研产出的统计与比较上,少见“投入—产出”间的绩效分析。本研究以福建省重点实验室为研究样本,通过计量模型定量分析实验室资金投入、劳动力投入、人力资本构成、对外学术交流情况等因素对实验室论文发表、专利授权、人才培养及经济收入的显著影响;对比研究高校科研院所重点实验室与企业重点实验室建设成效的差异,从“投入—产出”视角研究福建省重点实验室创新绩效关系。结果表明:(1)年轻科研人员所占比重、高级职称人员所占比重、高端人才所占比重、学术交流次数,实验室所在城市的整体受教育水平与R&D投资水平均对论文产出有显著的正向影响;实验室承担项目经费与科研用房面积对专利授权有着显著的积极影响;高级职称人员及高端人才能显著增加硕博人才的培养。(2)实验室投入整体上得到了相应回报。(3)高校科研院所重点实验室投入—产出的相关性远高于企业重点实验室,但成果转化仍存在不足。建议优化重点实验室评价体制,推动高校科研院所重点实验室与企业实质性的合作,提升创新成果的转化能力。

“迷雾中重生”:多重绩效反馈与企业数字化投入

多重绩效反馈是指决策时存在多个参照点,且决策主体存在多样性与群体性,致使绩效反馈出现多重性,多重绩效反馈状态可用绩效反馈相关性指标度量。企业数字化投入与其自身绩效反馈状态息息相关,多重绩效反馈下企业如何通过数字化投入实现“涅槃重生”是企业数字化转型须关注的重要问题。本文基于2007—2020年沪深A股上市公司数据,探究了绩效反馈相关性对企业数字化投入的作用,得到如下结论:绩效反馈相关性与企业数字化投入呈U形关系。对绩效反馈相关性进行细分后发现,绩效反馈一致性顺差、一致性落差以及不一致性均提升了企业数字化投入水平;研发背景高管权力深度强化了前述关系;研发背景高管权力广度弱化了绩效反馈相关性、绩效反馈一致性顺差与数字化投入间的关系;董事会正式权力层级强化了绩效反馈相关性与数字化投入的U形关系;董事会非正式权力层级强化了绩效反馈一致性落差与企业数字化投入的关系。考虑企业产权性质,非国有企业的调节作用基本能得到验证;考虑行业属性,在数字产业化企业样本中,多重绩效反馈对企业数字化投入的影响并不明显。本文对多重绩效反馈状态下企业数字化投入行为进行刻画,并考虑了研发背景高管权力结构与董事会权力层级的因素,研究结论有助于企业加深数字化投入决策前置因素的认识,也有助于政府合理制定企业数字化转型支持政策。