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The segmentation of printed circuit board (PCB) images is an important process in PCB inspection. The circuit traces, pads and vias in a PCB are dense and curved, and the PCB image obtained using different cameras or in different conditions may exhibit a large image gradient, which leads to inaccuracy and inefficiency in the PCB image segmentation. This paper aims to propose an improved local binary fitting level set method with prior graph cut, aiming to improve the accuracy and efficiency of the segmentation of PCB images obtained using different cameras or in different environments.

First, the paper constructs a 4-connected undirected graph using a given PCB image and classifies it based on the graph cut. Second, an adaptive initialization level set is implemented using the priori information obtained from the graph cut. Finally, the paper constructs a priori energy term using the prior information and introduces it into the energy function of the level set.

The approach results in an improved accuracy of segmentation in the context of a large gradient within the image. Experimental results demonstrate that the method can solve the deviation of artificially initialized level set from targets and improve the efficiency and accuracy of segmentation.

This study only considers level set method as the research object. Iteration of the level set method takes a long time for a given huge PCB picture, which makes it impossible to apply to scenes with high real-time requirements.

PCB image segmentation is an important process in the PCB inspection. Since template matching and morphology techniques are well-established, image segmentation quality has a significant impact on the accuracy of detection.

This paper studies the segmentation of PCB images, improves the efficiency and accuracy of segmentation and facilitates the subsequent applications, such as in the nondestructive testing of PCB.

The purpose of this paper is to investigate the effects of chloride ion concentration and applied bias voltage on the electrochemical migration (ECM) behavior between Cu and Ag under an NaCl thin electrolyte layer (TEL).

A self-made experimental setup for the ECM behavior between Cu and Ag was designed. An HD video measurement microscopy was used to observe the typical dendrite/corrosion morphology and pH distribution. Short-circuit time (SCT), short-circuit current density and the influence of the galvanic effect between Cu and Ag on their ECM behavior were studied by electrochemical tests. The surface morphology and composition of dendrite were characterized by FESEM/EDS.

The SCT increased with increasing NaCl concentration but decreased with increasing applied bias voltage, and the SCT between Cu and Ag was less than that between Cu and Cu because their galvanic effect accelerated the dissolution and migration of Cu. When NaCl concentration was less than or equal to 6 mmol/L, cedar-like dendrite was formed, whereas no dendrite formed and only precipitation occurred at high chloride ion concentration (100 mmol/L). The composition of the dendrite between Cu and Ag was copper.

The significance of this study is to clarify the ECM failure mechanism of printed circuit board (PCB) with an immersion silver surface finish (PCB-ImAg).

This study provides a basic theoretical basis for the selection of protective measures and metal coatings for PCB.

The social implication of this study is to predict the service life of PCB.

The ECM behavior of dissimilar metals under a TEL was investigated, the influence of the galvanic effect between them on their ECM was discussed, and the SCT increased with increasing NaCl concentration.

Studies on China suggest that institutional environment plays a significant role in business activities; however, the issue of how firms attend to institutional environment is largely under-explored. This paper responds to the oversight by examining the potential ways in which firms can demonstrate heterogeneity in terms of vigilance to government policy. Drawing from the attention-based view of firms and the institutional logic perspective, the authors aim to propose that firms with market logic or non-market logic will show difference in vulnerability to policy change. Further, firm ownership type and policy-leveraging capability would moderate the relationship between institutional logic and attention to policy environment.

The empirical background of this study is based on Chinese pharmaceutical firms. The new reform on health-care system launched by Chinese government in 2009 provides a fertile context to observe firms’ attention to government policy. The hypotheses are tested by using data of 145 Chinese pharmaceutical public firms from 2009 to 2013.

The results generally support the hypotheses: market logic has a positive effect on attention to policy, whereas non-market logic has a negative effect. The impact of market logic is weakened when firms have a higher policy-leveraging capability (in terms of getting government subsidies); the non-market logic effect is strengthened both when firms are state-owned enterprises and have a higher policy-leveraging capability.

Instead of focusing on how institutional environment have an influence on firm behavior as previous studies do, this paper examines the interaction between institution and firms by exploring how firms pay attention to government policy. Under the context of China, this study sheds light on how institutional logic plays a role in determining cognitive resource allocation of firms.

The purpose of this paper is to investigate the effects of network strength, transaction‐specific investments and inter‐personal trust on business relationship satisfaction for small‐and‐medium‐sized enterprises (SMEs) involved in agri‐food processing and exporting in China.

Survey data collected from 80 agri‐food SMEs in Jiangsu Province were used for empirical testing. The authors applied an ordered logit regression approach for model estimation.

The results demonstrate that strong guanxi networks, high level of transaction‐specific investments and inter‐personal trust significantly contribute to a high level of relationship satisfaction for agri‐food SMEs in China. In addition, inter‐personal trust shows a moderating effect on the relationship between transaction‐specific investments and relationship satisfaction.

Business relationships play a critical role in the modern market environment. Relational arrangements (based on guanxi and inter‐personal trust) should be further enhanced in order to yield satisfied business relationships for SMEs in China.

The paper extends our understanding of relationship (guanxi) marketing, as well as marketing practices for agri‐food SMEs in China.

Following a guanxi value – buyer‐seller relationship quality – marketing behaviour scheme, this paper aims to explore how traditional guanxi supports small vegetable farmers in modern markets in China.

Fieldwork was performed in Jiangsu Province, PR China. A stratified random sample of 167 vegetable farmers provided data for empirical testing with partial least squares analysis.

The findings suggested that the value of guanxi networks is an antecedent to buyer‐seller relationship quality and marketing behaviour in China. Guanxi networks improve the quality of buyer‐seller relationships in terms of interpersonal trust and satisfaction. Buyer‐seller relationships influence smallholders' transaction relationships, their participation in modern markets and choice for formal contracts. Guanxi networks not only support Chinese small‐scale vegetable farmers to get access to modern high‐value markets (e.g. supermarkets and international markets), but also encourage informal transactions in the vegetable business.

Guanxi networks play a critical role in the modern marketing environment in China. Marketing strategies based on personal relationships should be further enhanced in order to increase participation of smallholders in modern markets.

Quantitative evaluation of the effects of the Chinese cultural embedded concept of guanxi in the Chinese agrifood sector fills in an important research gap.

As a commonly engine coolant, ethylene glycol can produce corrosive acid byproducts at high temperatures when the car is running, specifically oxalic acid (OA), which can shorten the service life of engine. At the same time, chloride ions can also be introduced during coolant preparation processes. Therefore, this paper aims to investigate the synergistic corrosion behavior of Cl⁻ and OA on ADC12 aluminum alloy.

The electrochemical tests, scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction and X-ray photoelectron spectroscopy) were used.

The results showed that the corrosion rate of the aluminum alloy increased with the increase of OA and Cl⁻ concentrations. After adding Cl⁻, the surface film of the aluminum alloy was further damaged, Cl⁻ has a synergistic effect with OA and their interaction further accelerated the corrosion of the aluminum alloy. Nevertheless, as the immersion time increased, the corrosion rate of the aluminum alloy gradually diminished due to the formation of aluminum oxalate.

The corrosion of ADC12 aluminum alloy was studied in OA, Cl⁻ and their mixed solutions; the synergistic effect of OA and Cl⁻ on the corrosion of ADC12 aluminum alloy was discussed, and aluminum oxalate formed inhibited its corrosion.

This paper investigates the relationship between plot size and fertilizer use efficiency (FE) in Chinese large-scale farming and searches for the underlying mechanisms that explain this relationship.

Based on a household- and plot-level data set of large-scale production units (LSPUs) from Jiangsu and Jiangxi Provinces, the technical and fertilizer use efficiency of large-scale rice production is estimated by applying a translog stochastic frontier production function. The authors impose a monotonicity condition on the translog frontier using a three-step procedure to get theoretically consistent efficiency estimates. A beta regression model is then used to explore the association between plot size and LSPUs' efficiency in fertilizer application.

The average FE for the sampled plots is around 30%, which shows a large potential for LSPUs to reduce fertilizer use. A U-shaped relationship is observed between plot size and FE. The authors relate this non-linear pattern to the substitution of labour with capital-intensive technology and the efficiency differences in terms of farming performance between family and hired workers.

First, according to the authors’ knowledge, this paper is a first attempt to study the size–efficiency relationship focussing on fertilization practices of large-scale farming. The second contribution lies in the large-scale ranges of the plot-level data set. Third, efforts are made to reveal the mechanisms determining the plot size–FE relationship. Fourth, the authors provide guiding evidence for policymaking, as they show that the size of individual plots deserves equal attention in land consolidation decisions. Methodologically, this paper improves existing estimates of single-factor technical efficiency issued from a restricted production frontier model.