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The purpose of this paper is to propose a defect detection method of bare printed circuit boards (PCB) with high accuracy.

First, bilateral filtering of the PCB image was performed in the uniform color space, and the copper-clad areas were segmented according to the color difference among different areas. Then, according to the chaotic characteristics of the spatial distribution and the gradient direction of the edge pixels on the boundary of the defective areas, the feature vector, which evaluates quantitatively the significant degree of the defect characteristics by using the gradient direction information entropy and the uniform local binary patterns, was constructed. Finally, support vector machine classifier was used for the identification and localization of the PCB defects.

Experimental results show that the proposed algorithm can accurately detect typical defects of the bare PCB, such as short circuit, open circuit, scratches and voids.

Considering the limitations of describing all kinds of defects on bare PCB by using single kind of feature, the gradient direction information entropy and the local binary patterns were fused to build a feature vector, which evaluates quantitatively the significant degree of the defect features.

Purpose – To review the place of bicycle transportation within the Chinese national objective of sustainable development.

Methodology – The chapter provides an analysis of the evolution of bicycle transportation policies in China, and a discussion of the latest developments in the function and operation of public bicycle hire schemes.

Findings – Due to high population density, the prevailing mix of land use and a lack of affordability of cars and motor scooters, bicycle transportation has historically been very common in the urban areas of China. However, since the 1990s, many Chinese cities implemented restrictive policies on the development of bicycle transportation and the modal share of bicycles has reduced sharply.

Practical implications – The chapter suggests that China would need to create favourable conditions for bicycle transportation in urban areas through means such as policy support, land use planning, use of economic levers and through creating an acceptable social and cultural atmosphere for cycling. Finally, the maintenance of a relatively high proportion of bicycle traffic would need to be regarded as an index for sustainable urban development.

The negative externalities of pesticide overuse increasingly concern the public. However, little empirical evidence has been provided for pesticide overuse and the relationship between the governmental agricultural extension system reforms and pesticide use in grain production from a nationwide perspective. The purpose of this paper is to estimate the productive effect and overuse of pesticides, and it also investigates the effect of the governmental agricultural extension system reforms on pesticide expenditure in rice, maize and wheat production in China.

A two-equation system model consisting of an exponential-specific damage-control production function and a pesticide use function is applied to the provincial-level data during the period 1985–2016.

While pesticide expenditure significantly increases grain productivity, the actual pesticide expenditure exceeds the economically optimal level. The commercialization reform of the governmental agricultural extension system contributed to the increase in pesticide expenditure. Moreover, the de-commercialization reform of the governmental agricultural extension system plays a limited role in pesticide reduction. Price fluctuations for grain and pesticide also impose significant effects on pesticide expenditure.

This study has two important policy implications for pesticide reduction in China. It is urgent to specify the functions of the governmental agricultural extension system, and encourage the development of the socialized agricultural technology service. More efforts should also be made to remove the bureaucratic intervention on the pricing mechanism of grain product and pesticide.

In order to understand the status of the bridge reinforcement process, the construction process monitoring of the reinforced bridge is carried out. The T-beam bridge was tested using the truck loading test. The displacements and concrete strains of the bridge at mid-span were measured during the test.

This paper describes an innovative technique, external prestressing, used to strengthen a 36-year-old prestressed T-beam bridge. This paper introduces the construction process of the prestressed reinforcement method, and makes a theoretical analysis of the reinforced bridge through the establishment of the reinforcement model.

This study showed that the structural capacity and performance of the bridge were enhanced with externally prestressed steel strand strengthening.

The innovative reinforcement method of prestressed T-shaped bridge is put forward, which has guiding significance for similar bridge reinforcement and maintenance.

This paper aims to provide an overview of education system reform in China since 1978, and its practical implications.

Data were collected from literature review and interview. An overview of education system reform and its practical implications was found through data analysis.

There has been two types of education system reforms in China since 1978. The first type is school education system reform, and the second is education management system reform.

A point arising is how to reform the education system at the national level.

This is the first time the researcher has studied education system reform and its characteristics in China since 1978, and it can help people to understand education system reform in China systematically.

By reviewing the related literature on the Jiaoshi Pinren Zhi (JPZ) system, this paper seeks to indicate that the implementation of JPZ not only has led to domestic brain drain and the imbalance of teachers' qualities between different areas and schools, but also has violated children's equal rights to education guaranteed by the Constitution and educational laws in PR China.

By analysing national policies and laws and some cases, the paper points out that the reforms on teachers' employment causes the imbalance of teachers' qualities between different areas and schools and it is against the principle of children's equal rights to education guaranteed by the Constitution and some educational laws in China.

Since the late 1980s, many reform initiatives have been launched in the context of the transition from planned economy to market economy in China.

The reforms on the teachers' employment system from “Tongyi Fenpei” (TF, a system of unified placement for all graduates) and the life‐time employment system to JPZ (a free contract employment system) is one of the important reform initiatives.

One of the essential components of China’s economic open door policy is the reform in its distribution system. So far the distribution reform has transformed China’s distribution system from being non‐responsive and supply‐driven to increasingly responsive and market‐ driven and the nature of exchange relationships among channel members has also changed. Consequently, the China market has become more accessible. This paper reviews a series of distribution reform programs and the emerging trends, highlights major changes in China’s distribution system, identifies the unresolved marketing and administration issues, and assesses their implications for the design of channel strategy, market entry strategy, and effective channel management in China.

The dynamic process of purifying emulsion using electromagnetic technique has been analyzed and studied via dynamics principles in this paper. Based on results, the purification equipment has been developed and installed in a cold rolling mill. The basic structure characteristics of the purification equipment were described in detail. The equipment of purifying emulsion using electromagnetic technique is of excellent characteristics, which has a strong magnetic field, low flow velocity and multi‐pass of emulsion. Emulsion purified in this way can be recycled and used again with cost reduction. The equipment can be used in many fields such as cold rolling mill and machinery.