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Article
Publication date: 6 February 2024

Yitian Xiao, Jiawu Dai and J. Alexander Nuetah

The purpose of this paper is to test the overshooting effects of monetary expansion on prices of agricultural products at farm production, processing and circulation stages in…

Abstract

Purpose

The purpose of this paper is to test the overshooting effects of monetary expansion on prices of agricultural products at farm production, processing and circulation stages in China, and to investigate the heterogeneity of the overshooting mechanisms in these three links.

Design/methodology/approach

Empirical results are obtained through the vector error correction model and the overshooting framework proposed by Saghaian et al. (2002b). Specifically, we first apply the Dickey–Fuller generalized least squares (DF-GLS) method to test the stationarity of the key variables, and then use the Johansen’s (1991) method to conduct the cointegration test. Finally, the vector error correction model is employed to examine the overshooting hypotheses in the three stages of China’s agricultural sector.

Findings

Empirical results indicate that overshooting of prices relative to monetary expansion in China’s agricultural sector is a common phenomenon, but with significant heterogeneity. Firstly, at the stage of agricultural production, the overshooting degree and restoration rate of material price are greater than those of agricultural products price. Secondly, at the processing stage of agricultural products, both the purchase price of agricultural products and industrial producer price have an overshooting effect, but the overshooting effect of the former is more significant than the latter. Thirdly, at the circulation stage of agricultural products, the overshooting coefficient of the wholesale price index of agricultural products is the most significant, while that of the retail and purchase price of agricultural products is not significant.

Originality/value

The paper contributes to proposing a comprehensive framework on testing the overshooting effects for three main stages of agricultural sector in China and empirically investigating the heterogeneity of the overshooting mechanisms in different stages with time series methods.

Details

China Agricultural Economic Review, vol. 16 no. 1
Type: Research Article
ISSN: 1756-137X

Keywords

Article
Publication date: 15 September 2023

Prabhakaran Koothu Kesavan, Umashankar Subramaniam and Dhafer Jaber Almakhles

This paper aims to present a cascaded pseudo derivative feedback (PDF) plus pseudo derivative feedback plus pseudo derivative feedforward (PDFF) controller for a permanent magnet…

Abstract

Purpose

This paper aims to present a cascaded pseudo derivative feedback (PDF) plus pseudo derivative feedback plus pseudo derivative feedforward (PDFF) controller for a permanent magnet synchronous motor (PMSM) to improve the transient response of the system.

Design/methodology/approach

Proportional integral (PI) plus PI controller and the proposed PDF plus PDFF controller are designed, stability analysis is performed using the extended root locus method, and the effect of the damping coefficient is also extensively studied to validate the robustness of the proposed controller.

Findings

When compared to a cascaded PI plus PI controller, the proposed control approach has a much shorter settling time for the entire system and a 50% reduction in overshoot in stator current under extensive variations in speed with load disturbance.

Originality/value

The proposed controller is programmed into an FPGA Altera Cyclone II and applied to a 1.5 kW laboratory prototype PMSM drive. The effectiveness of the proposed methods has been demonstrated experimentally throughout a wide variable speed range, from 0 to 157 rad/s at different load conditions.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 April 1993

Ming‐C. Cheng and Rambabu Chennupati

The concept of the evolution of the distribution function is used to derive an energy‐scale distribution that is able to describe transport phenomena, including inter‐valley…

Abstract

The concept of the evolution of the distribution function is used to derive an energy‐scale distribution that is able to describe transport phenomena, including inter‐valley transfer effect, in the scale as small as the energy relaxation time. The energy‐scale distribution is used to study the evolution of electrons in n‐type GaAs under the influence of rapid change in field. Results indicate that, near the peak of strong velocity overshoot or the bottom of pronounced undershoot in the Γ valley caused by the rapid change in field, the energy‐scale distribution can not respond as fast as the distribution function calculated from the Monte Carlo method. The average velocity resulting from the energy‐scale distribution therefore leads to less pronounced overshoot and undershoot than those obtained from the Monte Carlo method. However, since velocity overshoot and undershoot are not pronounced in the L‐valleys, the L‐valley energy‐scale distribution is in excellent agreement with that determined by the Monte carlo simulation.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 12 no. 4
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 7 February 2020

Hongli Cao, Ye He, Xiaoan Chen and Xue Zhao

The purpose of this paper is to take transient contact force response, overshoots and steady-state force tracking error problems into account to form an excellent force controller.

Abstract

Purpose

The purpose of this paper is to take transient contact force response, overshoots and steady-state force tracking error problems into account to form an excellent force controller.

Design/methodology/approach

The basic impedance function with a pre-PID tuner is designed to improve the force response. A dynamic adaptive adjustment function that combines the advantages of hybrid impedance and adaptive hybrid impedance control is presented to achieve both force overshoots suppressing and tracking ability.

Findings

The introduced pre-PID tuner impedance function can achieve more than the pure impedance function in aspects of converging to the desired value and reducing the force overshoots. The performance of force overshoots suppression and force tracking error are maintained by introducing the dynamic adaptive sigma adjustment function. The simulation and experimental results both show the achieved control performance by comparing with the previous control methods.

Practical implications

The implementation of the controller is easy and convenient in practical manufacture scenes that require force control using industrial robots.

Originality/value

A superior robot controller adapting to a variety of complex tasks owing to the following characteristics: maintenance of high-accuracy position tracking capability in free-space (basic capabilities of modern industrial robots); maintenance of high speed, stability and smooth contact performance in collision stage; and presentation of high-precision force tracking capability in steady contact.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 February 1982

R.K. COOK and Jeffrey FREY

A transport model has been developed which is reasonably accurate, and has proven quite efficient for the two‐dimensional numerical simulation of submicron‐scale Si and GaAs…

Abstract

A transport model has been developed which is reasonably accurate, and has proven quite efficient for the two‐dimensional numerical simulation of submicron‐scale Si and GaAs devices. In this model an approximate form of the energy‐transport equation is developed; this equation is easily included in otherwise‐conventional device simulation codes, which then require only slightly more solution time than standard models using field‐dependent transport coefficients. Calculations for 0.25 micron gate length Si and GaAs MESFET's show that velocity overshoot effects can be very important, particularly in the latter material; predicted saturation currents in the GaAs devices are almost three times larger than those that would have been predicted using conventional transport models. The model described, and its application in simulation programs, should find use in the design of submicron‐scale devices to properly take advantage of overshoot phenomena.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 1 no. 2
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 9 June 2021

Muhammad Aftab, Amir Rafique and Evan Lau

The sticky-price monetary model of exchange rate states the overshooting hypothesis as, exchange rate depreciation beyond its long-term value in response to an increase in money…

Abstract

Purpose

The sticky-price monetary model of exchange rate states the overshooting hypothesis as, exchange rate depreciation beyond its long-term value in response to an increase in money supply owing to the sticky nature of prices. Because of interest and relevance to policy, there is a huge extant literature on it but with mixed findings that suggest the need for further studies to refine the findings. Pakistan’s rupee exchange rate against the US dollar depreciated 128.44% over the period May 2007–December 2018. Considering this substantial decline in rupee's value, this study aims to examine either the rupee short-run value is over-shot of its long-term value.

Design/methodology/approach

This study uses a linear ARDL approach that segregates the short-run and long-run effects thus clarifying the premise of exchange rate overshooting. Furthermore, this study also uses nonlinear ARDL as a robustness check incorporating structural breaks.

Findings

Findings based on a linear model show evidence of exchange rate undershooting that means a positive money shock causes the exchange rate to appreciate. A nonlinear analysis also provides support to these findings. However, the increase in relative money supply has more such effect than that of a decrease in the relative money supply. Moreover, the authorities’ inclination to stabilize the exchange rate appreciates its short-run value.

Originality/value

This study substantiates the overshooting hypothesis literature by considering the role of asymmetric effects of exchange rate determinants and structural breaks that is a rare attempt in the extant literature.

Details

Journal of Chinese Economic and Foreign Trade Studies, vol. 15 no. 1
Type: Research Article
ISSN: 1754-4408

Keywords

Article
Publication date: 14 November 2016

Stuart Thomas and Jason Potts

The purpose of this paper is to investigate a competitive evolutionary process we call “innovation overshooting” that has been observed in equipment-based sports, using…

Abstract

Purpose

The purpose of this paper is to investigate a competitive evolutionary process we call “innovation overshooting” that has been observed in equipment-based sports, using windsurfing as a case study.

Design/methodology/approach

The case-study approach is based upon primary data gathered through semi-structured, in-depth interviews with pioneers of the case-study sport and through analysis of international and domestic industry publications and grey literature.

Findings

New sports, in particular equipment-based “lifestyle” sports, can experience a rapid rise in popularity but eventually technology-driven competition leads to equipment overshooting the capabilities and financial budgets of most users. This Schumpeterian market process leads to a rapid decline in participation and the eventual collapse of the market for the sport’s equipment.

Originality/value

Models of endogenous overshooting are established in the study of finance and business cycles, and have recently been extended to the music and design industry. The authors extend this to the sports equipment sector finding clear evidence of evolutionary competitive technological and market overshooting.

Details

Sport, Business and Management: An International Journal, vol. 6 no. 5
Type: Research Article
ISSN: 2042-678X

Keywords

Article
Publication date: 1 April 1992

Ming‐C. Cheng

Influence of forward scattering, including ionized‐impurity and polar optical‐phonon scattering, on electron transport phenomena in a 3‐valley n‐type GaAs model subjected to a…

Abstract

Influence of forward scattering, including ionized‐impurity and polar optical‐phonon scattering, on electron transport phenomena in a 3‐valley n‐type GaAs model subjected to a rapid change in field is studied. It is shown that the macroscopic effective mass of electrons in a nonparabolic band structure is smaller than the energy‐dependent effective mass, which is usually assumed for modeling of GaAs devices, during the interval of velocity overshoot when strong forward scattering is involved. As a consequence, the hydrodynamic transport model, where the macroscopic effective mass is assumed energy dependent, leads to a smaller overshoot velocity.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 11 no. 4
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 1 February 2023

Kaixin Li, Ye He, Kuan Li and Chengguo Liu

With the increasing demands of industrial applications, it is imperative for robots to accomplish good contact-interaction with dynamic environments. Hence, the purpose of this…

Abstract

Purpose

With the increasing demands of industrial applications, it is imperative for robots to accomplish good contact-interaction with dynamic environments. Hence, the purpose of this research is to propose an adaptive fractional-order admittance control scheme to realize a robot–environment contact with high accuracy, small overshoot and fast response.

Design/methodology/approach

Fractional calculus is introduced to reconstruct the classical admittance model in this control scheme, which can more accurately describe the complex physical relationship between position and force in the interaction process of the robot–environment. In this control scheme, the pre-PID controller and fuzzy controller are adopted to improve the system force tracking performance in highly dynamic unknown environments, and the fuzzy controller is used to improve the trajectory, transient and steady-state response by adjusting the pre-PID integration gain online. Furthermore, the stability and robustness of this control algorithm are theoretically and experimentally demonstrated.

Findings

The excellent force tracking performance of the proposed control algorithm is verified by constructing highly dynamic unstructured environments through simulations and experiments. In simulations and experiments, the proposed control algorithm shows satisfactory force tracking performance with the advantages of fast response speed, little overshoot and strong robustness.

Practical implications

The control scheme is practical and simple in the actual industrial and medical scenarios, which requires accurate force control by the robot.

Originality/value

A new fractional-order admittance controller is proposed and verified by experiments in this research, which achieves excellent force tracking performance in dynamic unknown environments.

Details

Industrial Robot: the international journal of robotics research and application, vol. 50 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 23 August 2011

Berk Gonenc and Hakan Gurocak

This paper aims to present a hybrid actuator controller to obtain fast and stiff position response without any overshoot by blending input signals of a DC servomotor and a…

Abstract

Purpose

This paper aims to present a hybrid actuator controller to obtain fast and stiff position response without any overshoot by blending input signals of a DC servomotor and a particle brake.

Design/methodology/approach

The hybrid actuator controller has a module to estimate instantaneous changes in inertia and a blending algorithm that adjusts input signals to the motor and the brake so that together, as a hybrid actuator, they can achieve a fast, stiff position response without overshoot. The control logic implemented in the controller is derived from the kinematics of the system. For the blending algorithm, two separate cases are explored in which the user has the option to either utilize the full‐braking capacity or specify a safe deceleration limit for the system.

Findings

The blending algorithm enables the system to operate nearly twice as fast as the motor‐only case without any overshoot or oscillations. The controller can reject inertial load changes and significant external disturbances.

Originality/value

Such hybrid actuators along with the developed controller can be used in robotics and automation to increase the system accuracy and operational speed resulting in higher production rates. In addition, much stiffer haptic force feedback interfaces for virtual reality applications can be designed with smaller actuators. The blending algorithm provides considerable improvements and uses a physics‐based simple and easy‐to‐implement structure.

Details

Industrial Robot: An International Journal, vol. 38 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

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