经济“助推器”还是“稳定器”:保险功能的理论与实证

通过构建保险与经济发展之间的理论模型,证实保险不是经济发展的“助推器”,而是经济发展的“稳定器”。基于1997—2016年数据的实证分析也证实了理论分析的结论;Garch模型的计算结果表明,保险为经济发展所提供的套期保值功能比较有限,相比较而言,保障功能较强的财产保险具有明显的套期保值效果;人身保险产品浓厚的投资色彩导致其贡献率较低"基于贡献率的模拟计算显示,中国保险业的发展还存在较大缺口,无法为经济发展提供全面的“保驾护航”功能.因此,坚持“保险姓保”、正视保险保障功能、重视保险缺口,是促进保险业健康发展的正确方向。

美国服务业的经济“稳定器”作用及其对中国的启示

近二十年来,美国宏观经济波动逐渐趋于稳定,同时其服务业比重也在不断提高,本文从实证分析的角度探讨了这两种经济现象之间是否存在着必然的联系。结果表明,服务业的增加值和就业增长率的波动幅度几乎相当于工业波动的二分之一,同时,服务业的相对波动性也小于国民经济的,而工业的相对波动性则大于国民经济的波动性,所以服务业对国民经济确实具有“稳定器”作用。这对我国具有一定的启示意义。

“助推器”还是“稳定器”:保险业对经济产出作用的经验证据

现存理论与已有实证结论就“我国保险业对经济产出发挥的作用及程度”问题尚未达成统一共识。本文运用1999年～2009年保险市场以及GDP的相关季度数据，使用向量误差修正模型（VECM）论证我国保险业对经济产出的现实作用。研究结果表明，近十年来，中国保险业主要发挥的是抑制经济波动的“稳定器”作用，而对经济增长的“助推器”作用并不明显。部分原因在于目前保险发展还处于一个粗放经营阶段。加大保险产品和服务创新，扩大保险资金的使用渠道，不仅是维护经济稳定发展的审耍保证．也是旱日成为经济“助推器”的必要前提。

“双支柱调控”与宏观经济“稳定器”的效应检验——基于多部门DSGE的比较分析

本文从实体经济可持续稳定发展视角,建立了多部门动态随机一般均衡模型,研究传统的单纯使用货币政策的"单支柱调控"与近年来加入宏观审慎管理的"双支柱调控"的宏观经济调节框架下,主要经济变量对资本流动、利率、技术等相关冲击下的反应程度,并进行福利损失比较,以此检验宏观审慎政策对宏观经济的"稳定器"作用。研究发现,引入宏观审慎管理实施"双支柱调控"后,对实体经济发展政策效应相对温和,既能够达到一定的宏观政策目标,又能够平抑政策传导波动,显示出宏观审慎作为宏观经济"稳定器"的作用。而单纯使用货币政策的"单支柱调控"背景下,在宏观经济过快上行方面,往往容易发挥比较显著的政策作用,但同时也非常猛烈;但应对经济下行则政策效应非常有限,甚至在一个相对长的区间趋于无效。福利损失分析结果显示,从发展可持续的视角出发,"双支柱调控"下的福利损失也显著低于单纯货币政策条件下的福利损失,体现了宏观审慎"稳定器"可以在一定程度上弥补消费者因经济波动而损失的福利。

DC microgrid stability control with constant power load:a review

The DC microgrid has the advantages of high energy conversion efficiency,high energy transmission density,no reactive power flow,and grid-connected synchronization.It is an essential component of the future intelligent power distribution system.Constant power load(CPL)will degrade the stability of the DC microgrid and cause system voltage oscillation due to its negative resistance characteristics.As a result,the stability of DC microgrids with CPL has become a problem.At present,the research on the stability of DC microgrid is mainly focused on unipolar DC microgrid,while the research on bipolar DC microgrid lacks systematic discussion.The stability of DC microgrid using CPL was studied first,and then the current stability criteria of DC microgrid were summarized,and its research trend was analyzed.On this basis,aiming at the stability problem caused by CPL,the existing control methods were summarized from the perspective of source converter output impedance and load converter input impedance,and the current control methods were outlined as active and passive control methods.Lastly,the research path of bipolar DC microgrid stability with CPL was prospected.

论社会中间阶层的和谐文化建设

社会中间阶层是“稳定器”和“推动器”的综合体,具有积极而又功利、理性但不安分、成就与失落并存等特征。要发挥其“稳定器”作用,抑制其不稳定作用,必须从社会文化、阶层发展、政治秩序、社会机制等方面着手,不断改善社会环境、塑造内在品质、容纳合理诉求、引领行为方式,建设和谐的中间阶层文化。

An Electrostatic MEMS Actuator with Large Displacement Under Low Driving Voltage

A comb-drive actuator for lateral movement of over 100μm under low driving voltage is designed. Side stability is analyzed to improve the performance of the actuator. According to the analysis,a comb-drive actuator with small comb gap,high-stiffness-ratio prebent suspension beams, non-initial overlap, and linear-engaged-length comb teeth is proposed and the parameters of the actuator are derived. Experiments indicate that the actuator resonates at 573Hz with a Q factor of 35.88 and reaches a maximum displacement of over 100μm at a driving voltage of 7IV,which fulfills the design requirements and matches the analytical value to within 2.1%.

Thermostability of Vane Absorber

Aim To improve the thermostability of vane absorbers while designing and manu- facturing. Methods Having considered the structural features of vane absorbers, measures that could reduce the force decay ratio of vane absorbers were discussed. A kind of practical auto temperature compensation apparatus, whose theoretical basis had been discussed, was designed. Results Compared to the prototype vane absorber, this kind of apparatus could decrease force decay ratio sharply. Thus, the thermostability of vane absorbers was improved greatly The accuracy of theoretical analysis and the effectiveness and feasibility of the apparatus was proved by actual testing Conclusion changing vane absorber's configuration, its performance is improved.

浅谈养老保险管理工作

养老保险工作是社会保障工作的重要组成部分,关系到企业职工的切身利益,关系到企业经济发展和社会稳定。就做好养老保险的基础、关键、核心及手段作了简要阐述。

A 16 bit Stereo Audio ΣΔ A/D Converter

A 16 bit stereo audio novel stability fifth-order ∑△ A/D converter that consists of switched capacitor ∑△ modulators, a decimation filter, and a bandgap circuit is proposed. A method for the stabilization of a high order single stage ∑△ modulator is also proposed. A new multistage comb filter is used for the front end decimation filter. The ∑△ A/D converter achieves a peak SNR of 96dB and a dynamic range of 96dB. The ADC was implemented in 0. 5μm 5V CMOS technology. The chip die area occupies only 4. 1mm × 2.4mm and dissipates 90mW.

STABILITY OF THE HIGH-ORDER BAM AND ITS PERFORMANCE ANALYSIS

High order bidirectional associative memory (HOBAM) by Tai et al is extension to Kosko′s bidirectional associative memory(BAM). It not only possesses merits of the BAM, but also relaxes the continuity assumption for reliable recalls and significantly improves the storage capacity and error correcting capability of the BAM. However, Tai′s performance analysis for the HOBAM is only limited in the computer simulations, in the other words, they did not give a theoretical analysis result. This paper fills the blank and gives a theoretical proof for HOBAM′s stability and storage capacity analysis so that the system can theoretically ensure all the training pattern pairs to become its stable points.

Robust adaptive dynamic surface control for nonlinear uncertain systems

We propose a new method for robust adaptive backstepping control of nonlinear systems with parametric uncertainties and disturbances in the strict feedback form. The method is called dynamic surface control. Traditional backstepping algorithms require repeated differentiations of the modelled nonlinearities. The addition of n first order low pass filters allows the algorithm to be implemented without differentiating any model nonlinearities, thus ending the complexity arising due to the 'explosion of terms' that makes other methods difficult to implement in practice. The combined robust adaptive backstepping/first order filter system is proved to be semiglobally asymptotically stable for sufficiently fast filters by a singular perturbation approach. The simulation results demonstrate the feasibility and effectiveness of the controller designed by the method.

Active Vibration Control and Stability Analysis of Cantilever Plate

Active vibration control and stability analysis of cantilever plate are discussed. Based on the analysis of characteristic equation of the closed loop control system, it is shown that such an active control may increase damping properties of the system, meanwhile it may result in instability of the system. It is stable when the feedback only occurs between the collocated sensors and actuators, but it may be unstable when there exists the feedback between sensors and actuators, which mainly depends on the property of the gain matrix of feedback. If the gain matrix is symmetric and definitely positive, the system is stable.

Power system stabilizer design using hybrid multi-objective particle swarm optimization with chaos

A novel technique for the optimal tuning of power system stabilizer (PSS) was proposed,by integrating the modified particle swarm optimization (MPSO) with the chaos (MPSOC).Firstly,a modification in the particle swarm optimization (PSO) was made by introducing passive congregation (PC).It helps each swarm member in receiving a multitude of information from other members and thus decreases the possibility of a failed attempt at detection or a meaningless search.Secondly,the MPSO and chaos were hybridized (MPSOC) to improve the global searching capability and prevent the premature convergence due to local minima.The robustness of the proposed PSS tuning technique was verified on a multi-machine power system under different operating conditions.The performance of the proposed MPSOC was compared to the MPSO,PSO and GA through eigenvalue analysis,nonlinear time-domain simulation and statistical tests.Eigenvalue analysis shows acceptable damping of the low-frequency modes and time domain simulations also show that the oscillations of synchronous machines can be rapidly damped for power systems with the proposed PSSs.The results show that the presented algorithm has a faster convergence rate with higher degree of accuracy than the GA,PSO and MPSO.

Design of an optimal active stabilizer mechanism for enhancing vehicle rolling resistance

Improving rollover and stability of the vehicles is the indispensable part of automotive research to prevent vehicle rollover and crashes.The main objective of this work is to develop active control mechanism based on fuzzy logic controller(FLC) and linear quadratic regulator(LQR) for improving vehicle path following,roll and handling performances simultaneously.3-DOF vehicle model including yaw rate,lateral velocity(lateral dynamic) and roll angle(roll dynamic) were developed.The controller produces optimal moment to increase stability and roll margin of vehicle by receiving the steering angle as an input and vehicle variables as a feedback signal.The effectiveness of proposed controller and vehicle model were evaluated during fishhook and single lane-change maneuvers.Simulation results demonstrate that in both cases(FLC and LQR controllers) by reducing roll angle,lateral acceleration and side slip angles remain under 0.6g and 4° during maneuver,which ensures vehicle stability and handling properties.Finally,the sensitivity and robustness analysis of developed controller for varying longitudinal speeds were investigated.

Finite-time Stabilization of the Double Integrator Subject to Input Saturation and Input Delay

Abstract--The time-optimal control design of the double integrator is extended to the finite-time stabilization design that compensates both input saturation and input delay. With the aid of the Artstein＇s transformation, the problem is reduced to assigning a saturated finite-time stabilizer. Index Terms--Finite-time stabilization, input delay, saturated design.

Transformer real-time reliability model based on operating conditions

Operational reliability evaluation theory reflects real-time reliability level of power system. The component failure rate varies with operating conditions. The impact of real-time operating conditions such as ambient temperature and transformer MVA (megavolt-ampere) loading on transformer insulation life is studied in this paper. The formula of transformer failure rate based on the winding hottest-spot temperature (HST) is given. Thus the real-time reliability model of transformer based on oper- ating conditions is presented. The work is illustrated using the 1979 IEEE Reliability Test System. The changes of operating conditions are simulated by using hourly load curve and temperature curve, so the curves of real-time reliability indices are ob- tained by using operational reliability evaluation.

Gravitational search algorithm for coordinated design of PSS and TCSC as damping controller

A newly developed heuristic global optimization algorithm, called gravitational search algorithm （GSA）, was introduced and applied for simultaneously coordinated designing of power system stabilizer （PSS） and thyristor controlled series capacitor （TCSC） as a damping controller in the multi-machine power system. The coordinated design problem of PSS and TCSC controllers over a wide range of loading conditions is formulated as a multi-objective optimization problem which is the aggregation of two objectives related to damping ratio and damping factor. By minimizing the objective function with oscillation, the characteristics between areas are contained and hence the interactions among the PSS and TCSC controller under transient conditions are modified. For evaluation of effectiveness and robustness of proposed controllers, the performance was tested on a weakly connected power system subjected to different disturbances, loading conditions and system parameter variations. The cigenvalues analysis and nonlinear simulation results demonstrate the high performance of proposed controllers which is able to provide efficient damping of low frequency oscillations.

Coordinated and uncoordinated design of LFO damping controllers with IPFC and PSS using ICA and SFLA

A single machine-infinite-bus(SMIB) system including the interline power flow controllers(IPFCs) and the power system stabilizer(PSS) controller is addressed. The linearized system model is considered for investigating the interactions among IPFC and PSS controllers. To improve the stability of whole system again different disturbances, a lead-lag controller is considered to produce supplementary signal. The proposed supplementary controller is implemented to improve the damping of the power system low frequency oscillations(LFOs). Imperialist optimization algorithm(ICA) and shuffled frog leaping algorithm(SFLA) are implemented to search for optimal supplementary controllers and PSS parameters. Moreover, singular value decomposition(SVD) method is utilized to select the most effective damping control signal of IPFC lead-lag controllers. To evaluate the system performance, different operating conditions are considered. Reponses of system in five modes including uncoordinated and coordinated modes of IPFC and PSS using ICA and SFLA are studied and compared. Considering the results, response of system without controller shows the highest overshoot and the longest settling time for rotor angel at the different operating conditions. In this mode of system, rotor speed has the highest overshoot. Rotor angel in the system with only PSS includes lower overshoot and oscillation than system without controller. When PSS is only implemented, rotor speed deviation has the longest settling time. Rotor speed deviation in the uncoordinated mode of IPFC and PSS shows lower overshoot than system with only PSS and without controller. It is noticeable that in this mode, rotor angel has higher overshoot than system with only PSS. The superiority of the suggested ICA-based coordinated controllers is obvious compared with SFLA-based coordinated controllers and other system modes. Responses of coordinated PSS and IPFC SFLA-based supplementary controllers include higher peak amplitude and longer settling time compared with coordinated IPFC and PSS ICA-based controllers. This comparison shows that overshoots, undershoots and the settling times are reduced considerably in coordinated mode of IPFC based controller and PSS using ICA. Analysis of the system performance shows that the proposed method has excellent response to different faults in power system.

Robust simultaneous tracking and stabilization of wheeled mobile robots not satisfying nonholonomic constraint

A robust unified controller was proposed for wheeled mobile robots that do not satisfy the ideal rolling without slipping constraint.Practical trajectory tracking and posture stabilization were achieved in a unified framework.The design procedure was based on the transverse function method and Lyapunov redesign technique.The Lie group was also introduced in the design.The left-invariance property of the nominal model was firstly explored with respect to the standard group operation of the Lie group SE(2).Then,a bounded transverse function was constructed,by which a corresponding smooth embedded submanifold was defined.With the aid of the group operation,a smooth control law was designed,which fulfills practical tracking/stabilization of the nominal system.An additional component was finally constructed to robustify the nominal control law with respect to the slipping disturbance by using the Lyapunov redesign technique.The design procedure can be easily extended to the robot system suffered from general unknown but bounded disturbances.Simulations were provided to demonstrate the effectiveness of the robust unified controller.