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The purpose of this paper is to examine whether Chinese pork reserve regulation policy fulfills its function in stabilizing market prices and simultaneously to theoretically and empirically analyze the causes leading to the failure of Chinese Government’s intervention in the market, especially in the context of asymmetric pork and hog price information transmission.

A modified Reserve-Cobweb model based on the competitive storage model developed by Muth in 1961 is employed to examine the transmission effect of hog and pork prices under the setting of Chinese Government’s pork reserve regulation policy, using the data on Chinese hog and pork prices from June 2009 to June 2015.

While the Reserve-Cobweb model provides theoretical insights, suggesting that the implementation of the government’s reserve policy tool to control price volatility actually leads to increased price volatility, the empirical results indicate that the policy induces hypercorrection and impels greater price volatility, especially in the context of existence of asymmetric price information transmission.

The Chinese Government should reduce excessive pork price intervention and instead allow the market to play its role in the hog and pork markets.

This paper develops a modified Reserve-Cobweb model based on the price transmission effect on different links within the agricultural products supply chain, which is used to empirically validate the existence of asymmetric price information transmission between pork and hog price in China.

This paper aims to examine whether China's grain price support policy has distorted the grain market price.

The time-varying differences-in-differences (DID) model is used to study the impact of support policies on grain prices, and it is combined with the event study method to explore the dynamic effects of price support policy. Panel data model is used to study the effect of the price support policy on price formation for national grain market prices. In addition, we apply the smooth transformation (STR) model to verify whether there is a distortion in the transmission of grain prices among different markets in China and from the international market to China’s market.

China’s grain price support policy plays a significant role in rising grain market prices, weakens the decisive role of the market mechanism in the formation of grain prices, hinders the spatial transmission of market price signals and decreases the effect of price transmission from the world market to China’s market.

In order to ensure both the stability of grain production as well as the market stability, and also to ensure that intervention policies do not distort the food market, the minimum purchase price of grain and market regulation policies should be adjusted as follows: (1) price support policy should be shifted to an income support policy and (2) reasonably determine the scale of reserves and implement a grain minimum purchase price policy in limited areas.

Our findings are relevant for understanding the effect of China's grain price support policies on the implementation regions and the price transmission effect, which provide reference experience for developing countries to implement food price policies.

Modelling accurately the transient behaviour of natural convection flow in enclosures been a challenging task because of a variety of numerical errors which have limited achieving the higher order temporal accuracy. A fourth-order accurate finite difference method in both space and time is proposed to overcome these numerical errors and accurately model the transient behaviour of natural convection flow in enclosures using vorticity–streamfunction formulation.

Fourth-order wide stencil formula with appropriate one-sided difference extrapolation technique near the boundary is used for spatial discretisation, and classical fourth-order Runge–Kutta scheme is applied for transient term discretisation. The proposed method is applied on two transient case studies, i.e. convection–diffusion of a Gaussian Pulse and Taylor Vortex flow having analytical solution.

Error magnitude comparison and rate of convergence analysis of the proposed method with these analytical solutions establish fourth-order accuracy and prove the ability of the proposed method to truly capture the transient behaviour of incompressible flow. Also, to test the transient natural convection flow behaviour, the algorithm is tested on differentially heated square cavity at high Rayleigh number in the range of 10³-10⁸, followed by studying the transient periodic behaviour in a differentially heated vertical cavity of aspect ratio 8:1. An excellent comparison is obtained with standard benchmark results.

The developed method is applied on 2D enclosures; however, the present methodology can be extended to 3D enclosures using velocity–vorticity formulations which shall be explored in future.

The proposed methodology to achieve fourth-order accurate transient simulation of natural convection flows is novel, to the best of the authors’ knowledge. Stable fourth-order vorticity boundary conditions are derived for boundary and external boundary regions. The selected case studies for comparison demonstrate not only the fourth-order accuracy but also the considerable reduction in error magnitude by increasing the temporal accuracy. Also, this study provides novel benchmark results at five different locations within the differentially heated vertical cavity of aspect ratio 8:1 for future comparison studies.

The aim of this paper is to propose a robust robot fuzzy logic proportional-derivative (PD) controller for trajectory tracking of autonomous nonholonomic differential drive wheeled mobile robot (WMR) of the type Quanser Qbot.

Fuzzy robot control approach is used for developing a robust fuzzy PD controller for trajectory tracking of a nonholonomic differential drive WMR. The linear/angular velocity of the differential drive mobile robot are formulated such that the tracking errors between the robot’s trajectory and the reference path converge asymptotically to zero. Here, a new controller zero-order Takagy–Sugeno trajectory tracking (ZTS-TT) controller is deduced for robot’s speed regulation based on the fuzzy PD controller. The WMR used for the experimental implementation is Quanser Qbot which has two differential drive wheels; therefore, the right/left wheel velocity of the differential wheels of the robot are worked out using inverse kinematics model. The controller is implemented using MATLAB Simulink with QUARC framework, downloaded and compiled into executable (.exe) on the robot based on the WIFI TCP/IP connection.

Compared to other fuzzy proportional-integral-derivative (PID) controllers, the proposed fuzzy PD controller was found to be robust, stable and consuming less resources on the robot. The comparative results of the proposed ZTS-TT controller and the conventional PD controller demonstrated clearly that the proposed ZTS-TT controller provides better tracking performances, flexibility, robustness and stability for the WMR.

The proposed fuzzy PD controller can be improved using hybrid techniques. The proposed approach can be developed for obstacle detection and collision avoidance in combination with trajectory tracking for use in environments with obstacles.

A robust fuzzy logic PD is developed and its performances are compared to the existing fuzzy PID controller. A ZTS-TT controller is deduced for trajectory tracking of an autonomous nonholonomic differential drive mobile robot (i.e. Quanser Qbot).

This chapter examines the changing state–university–student relationships in post/socialist China since the late 1980s. We begin with an introduction to four salient themes in scholarship on Chinese post/socialism that are highly relevant to higher education: globalization, gradualism, civic society, and a critique of holism. These themes help us explain interrelated educational trends that affect the state–university–student relationship: the globalization, “massification,” and stratification of higher education; the redefined role of the state in university governance and management; higher education marketization and privatization; and the quest for meaning and (e)quality in and through higher education. Our general argument is that during the “socialist” period the main relationship central to higher learning was between the state and students. Universities were agents of the state; from a legal point of view, indeed, universities did not have an independent status from the state. In the “post-socialist” era the university–student relationship has become more significant. We examine this reconfiguration through two case studies, one on the development of college student grievance and rights consciousness, and the other on reforms in higher education student services administration. When looked at from the point of view of the state, we see that appropriation and implementation of policies and regulations shaping student rights and services are in partial contradiction with state policies to accelerate economic growth and bolster party authority. From the point of view of universities, we see institutions grappling with how to deliver on forward-looking structures and actions while navigating between the state's policy mandates and growing expectations and demands of its student and business stakeholders. From the point of view of students, we see how constrained agency, uncertainty, and the power of the credential motivates social praxis. At all levels of the state–institution–student relationship actors are employing a kind of pragmatic improvisation (one of the salient features of post/socialism) captured by the well-known Chinese proverb “groping for stones to cross the river.” This saying is an apt metaphor for the tentative searching by state, institution, and individual for a safe foothold in the post/socialist world.