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In China, rural-to-urban migrant workers who are from the same place of origin tend to concentrate in the same workplace. If the concentration is sufficiently dense, it means that these migrant workers build up a social network which could be defined as native place enclave (NPE). In this paper, the authors discussed whether there are behavioral differences between enclave workers and non-enclave workers when they have conflicts with their employers.

The authors put two questions to empirical tests. First, do enclave workers experience less sense of deprivation than non-enclave workers? Second, compared to non-enclave workers, are enclave workers more willing to participate in collective action against their employers? Using data from a survey of migrant workers in Pearl River Delta and Yangzi River Delta in 2010, the authors made a comparison between enclave workers and non-enclave workers with respect to sense of deprivation and willingness-to-participate by using a propensity score matching method.

The authors found that the relationship between NPE and sense of deprivation was negative, so was the relationship between NPE and willingness-to-participate. Meanwhile, the two relationships were stronger than what had been found after the propensity score matching method was used.

The results implied that employers can reduce labor conflicts by using NPE to mitigate migrant workers’ sense of deprivation and by lowering the risk of their collective actions. In this way, NPE may contribute to the upkeep of workplace order and even social order.

There have been hot debates on how NPE would affect migrant workers’ collective action. Resource mobilization theory pointed out that NPE was positively related to workers’ collective action while production politics theory held an opposite view. Our findings provided empirical evidences for the debates.

This paper aims to study the sampling methods (or design of experiments) which have a large influence on the performance of the surrogate model. To improve the adaptability of modelling, a new sequential sampling method termed as sequential Chebyshev sampling method (SCSM) is proposed in this study.

The high-order polynomials are used to construct the global surrogated model, which retains the advantages of the traditional low-order polynomial models while overcoming their disadvantage in accuracy. First, the zeros of Chebyshev polynomials with the highest allowable order will be used as sampling candidates to improve the stability and accuracy of the high-order polynomial model. In the second step, some initial sampling points will be selected from the candidates by using a coordinate alternation algorithm, which keeps the initial sampling set uniformly distributed. Third, a fast sequential sampling scheme based on the space-filling principle is developed to collect more samples from the candidates, and the order of polynomial model is also updated in this procedure. The final surrogate model will be determined as the polynomial that has the largest adjusted R-square after the sequential sampling is terminated.

The SCSM has better performance in efficiency, accuracy and stability compared with several popular sequential sampling methods, e.g. LOLA-Voronoi algorithm and global Monte Carlo method from the SED toolbox, and the Halton sequence.

The SCSM has good performance in building the high-order surrogate model, including the high stability and accuracy, which may save a large amount of cost in solving complicated engineering design or optimisation problems.

This paper aims to present a robust method for the determination of α- and ß-2, 7, 11-cembratriene-4, 6-diols (α, ß-CBT-diol) in tobacco samples which was developed and validated by using the self-made α, ß-CBT-diol with higher purity as the standard.

After the ultrasonic extraction and clean-up procedures, samples were analyzed by gas chromatography/mass spectrometry in selected ion monitoring mode and full scan mode at the same time. A 1-heptadecanol was used as an internal standard. The important parameters, such as extraction conditions and derivation conditions, were optimized.

Under the optimal conditions, good results in terms of linearity (R² > 0.999) and recoveries (93.2-107 per cent) were achieved. The limits of detection were 0.120 and 0.180 μg/ml for α- and ß-CBT-diol, respectively. α, ß-CBT-diol level of analyzed tobacco was found in the range of 34.2-1.26 × 103 μg/g with relative standard deviations below 6 per cent.

Such a strategy opens a new door towards the development of a simple, robust and sensitive method for the determination of α, ß-CBT-diol in real samples.

The purpose of this paper is to present the landscape of the cash-per-publication reward policy in China and reveal its trend since the late 1990s.

This study is based on the analysis of 168 university documents regarding the cash-per-publication reward policy at 100 Chinese universities.

Chinese universities offer cash rewards from USD30 to USD165,000 for papers published in journals indexed by Web of Science, and the average reward amount has been increasing for the past ten years.

The cash-per-publication reward policy in China has never been systematically studied and investigated before except for in some case studies. This is the first paper that reveals the landscape of the cash-per-publication reward policy in China.

This paper aims to investigate the influence of laser energy density on microstructure and mechanical properties of the selective laser melted (SLMed) Ti6Al4V to complement the existing knowledge in additive manufacturing of Ti6Al4V for future application of selective laser melting (SLM) in fabricating Ti6Al4V parts.

Ti6Al4V alloy is fabricated by SLM by adopting various energy densities. Microstructures and mechanical properties of the Ti6Al4V deposited using different energy densities are characterized.

Both high relative densities and microhardness can be obtained in the optimized processing window. The decrease of martensite width and spacing can improve the microhardness on both XOY and XOZ sections when the applied E_V (defined as the laser energy per unit volume) increases. The width of the columnar grain increases with E_V, resulting in a stronger anisotropy in microhardness between XOY and XOZ sections. Residual tensile stresses exist in the SLMed Ti6Al4V and increase with an increasing E_V. A tensile strength of 1,268 MPa, a yield strength of 1,030 MPa, and an elongation of 4% can be obtained by using the optimized range of E_V.

The microstructure of SLMed Ti6Al4V is quantitatively analysed by measuring the size of columnar grains and the martensites. The anisotropy of microstructures and properties in SLMed Ti6Al4V is characterized and its dependence on laser energy density is established. The residual stress in SLMed Ti6Al4V is characterized and its dependence on laser energy density is established. An optimized processing window to deposit Ti6Al4V alloy by SLM is proposed.

This paper aims to expand the application area of Inconel 718 alloy in marine environment, the sensitivity of pitting corrosion should be analyzed and discussed, especially the effect of block carbides.

Effect of carbides on the sensitivity of pitting corrosion for Inconel 718 alloy was carried out at 30°C in 3.5% NaCl solution using dynamic electrochemical impedance spectroscopy and anodic polarization techniques. In addition, the initiation of pitting corrosion was investigated by immersion test in 0.05 M HCl + 6% FeCl₃ solution.

As a result, the precipitation of carbides, as the initiation of pitting corrosion, increased pitting corrosion susceptibility, especially the block carbides could lead to deep-spalling. Within that process, temperature and potential acted as the main controlling factors, and the effect of the latter was more distinct.

The initiation of pitting corrosion was revealed by the immersion test. The mechanism of pitting corrosion was analyzed and discussed.

The purpose of this paper is to design a decoding software for the Reed‐Solomon (RS) codes, which are using an efficient degree computationless algorithm based on the Euclidean algorithm. As a consequence, the complexity of this new decoding algorithm is dramatically reduced.

Applying the rules of polynomial in finite field, operation modules which can carry out multiplication, inverse calculation in GF(2⁸) are designed with “C++” language, and a RS codec software based on these is implemented. In this software, the new decoding algorithm computes the error locator polynomial and the error evaluator polynomial simultaneously without performing polynomial divisions, and there is no need for the degree computation cell and the degree comparison cell.

Owing to the help of this software, the paper can easily perform the RS code for different values of t and different primitive polynomials over GF(2^m) without re‐designing the programme.

It will be served as an efficient auxiliary technique for algorithm development and verification together with hardware design and debugging. Furthermore, an illustrative example of (255, 223) RS code using this program shows that the speed of the decoding process is approximately three times faster than that of the conventional decoding software.

Bike sharing becomes suddenly hot up in China since the end of 2016. However, few studies have focused on shared bicycle users’ behavior. To fill this research gap, this paper aims to develop an integrated model to investigate factors that affect shared bicycle users’ subjective well-being.

A field survey with 220 shared bicycle users is conducted to test the research model and hypotheses.

The highlights are that perceived value has positive effect on users’ life satisfaction. Specially, it is interesting to find that hedonic value has the greatest impact on users’ life satisfaction, followed by social value and utilitarian value. Perceived risks which including privacy risks, financial risks and functional risks act as a moderating role between perceived value and users’ life satisfaction.

First, the authors clear factors that affect users’ subjective well-being from the perspective of perceived value. The results deepen our understanding about the effect of perceived value on users’ subjective well-being. Second, the current researches have ignored the effect of perceived risks on users’ subjective well-being. The authors filled that gap and found that perceived risks which including privacy risks, financial risks and functional risks act as a moderating role between perceived value and users’ subjective well-being.