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Getting high-quality data by removing the noisy data from the user-generated content (UGC) is the first step toward data mining and effective decision-making based on ubiquitous and unstructured social media data. This paper aims to design a framework for revoking noisy data from UGC.

In this paper, the authors consider a classification-based framework to remove the noise from the unstructured UGC in social media community. They treat the noise as the concerned topic non-relevant messages and apply a text classification-based approach to remove the noise. They introduce a domain lexicon to help identify the concerned topic from noise and compare the performance of several classification algorithms combined with different feature selection methods.

Experimental results based on a Chinese stock forum show that 84.9 per cent of all the noise data from the UGC could be removed with little valuable information loss. The support vector machines classifier combined with information gain feature extraction model is the best choice for this system. With longer messages getting better classification performance, it has been found that the length of messages affects the system performance.

The proposed method could be used for preprocessing in text mining and new knowledge discovery from the big data.

Existing control circuits for piezoelectric energy harvesting (PEH) suffers from long startup time or high power consumption. This paper aims to design an ultra-low power control circuit that can harvest weak ambient vibrational energy on the order of several microwatts to power heavy loads such as wireless sensors.

A self-powered control circuit is proposed, functioning for very brief periods at the maximum power point, resulting in a low duty cycle. The circuit can start to function at low input power thresholds and can promptly achieve optimal operating conditions when cold-starting. The circuit is designed to be able to operate without stable DC power supply and powered by the piezoelectric transducers.

When using the series-synchronized switch harvesting on inductor circuit with a large 1 mF energy storage capacitor, the proposed circuit can perform 322% better than the standard energy harvesting circuit in terms of energy harvested. This control circuit can also achieve an ultra-low consumption of 0.3 µW, as well as capable of cold-starting with input power as low as 5.78 µW.

The intermittent control strategy proposed in this paper can drastically reduce power consumption of the control circuit. Without dedicated cold-start modules and DC auxiliary supply, the circuit can achieve optimal efficiency within one input cycle, if the input signal is larger than voltage threshold. The proposed control strategy is especially favorable for harvesting energy from natural vibrations and can be a promising solution for other PEH circuits as well.

This paper aims to study a multi-level reinjection current source converter (MLR-CSC) that adds attracting properties such as the self-commutation and pulse multiplication to the thyristor converter, which is of great significance for increasing the device capacity and reducing current harmonics on the grid side. Particularly, designing advantageous driving methods of the reinjection circuit is a critical issue that impacts the harmonic reduction and operation reliability of the MLR-CSC.

To deal with the mentioned issue, this paper takes the five-level reinjection current source converter (FLR-CSC), which is a type of the MLR-CSC, as the research object. Then, a method that can fully use combinations of five-level reinjection switching functions based on the concept of decomposition and recombination is proposed. It is worthy to mention that the proposed method can be easily extended to other multi-level reinjection circuits. Moreover, the working principle of the three-phase bridge circuit based on semi-controlled thyristors in the FLR-CSC that can achieve the four-quadrant power conversion is analyzed in detail.

Finally, the simulation and experimental results of FLR-CSC verify the effectiveness of the proposed reinjection circuit driving method and the operating principle of four-quadrant power conversion in this paper.

The outstanding features of the proposed driving method for FLR-CSC in this paper include combinations of reinjection switching functions that are fully exploited through three simple steps and can be conveniently extended to other multi-level reinjection circuits.

This paper aims that mobile health (mHealth) applications have emerged as a key tool to support public health. However, there are only a few studies examining the influences of health-related ascribes on continuance intention to use mHealth apps and how these influences are contingent on gender in the mHealth app using context.

This study takes the protection motivation theory as a theoretical framework to examine the ordered relationship between threat and coping appraisals and their impacts on continuance intention to use mHealth apps. In addition, this study further extends the literature on gender differences into the mHealth app's context to investigate the moderating role of gender. The suggested hypotheses are confirmed by a structural equation modeling approach and multigroup investigation employing survey data of 345 users of Spring Rain Doctor in China, a typical mHealth app.

The findings suggest that the impact of perceived disease threat on user's continuance intention is mediated entirely by coping appraisals. Furthermore, the three coping appraisals' impacts are contingent upon gender. Specifically, response efficacy is more crucial for male users in forecasting continuance intention, whereas self-efficacy and response cost have a more salient influence on continuance intention for female users.

This study examines the ordered influences of threat and coping appraisal, moderated by gender, on continuance intention on use mHealth apps. These findings could contribute to relevant theoretical and practical implications.

By adopting learning theory and a guanxi perspective, this study aims to investigate the effects of interpersonal guanxi (interpersonal networks or connections) and relationship learning on companies’ business performance when operating in a large emerging market.

Using a sample of 294 sales managers and salespeople in the Chinese hotel sector, the authors empirically test the authors' arguments through a structural equation modeling (SEM) approach.

The authors' findings indicate that strong interpersonal guanxi tends to generate more positive business performance. Furthermore, the authors find that relationship learning plays a mediating role in the association between interpersonal guanxi and hotel companies’ business performance in a Chinese context. Finally, the authors empirically explore the moderating effect of inter-firm dependence on the contribution of interpersonal guanxi to relationship learning. Findings demonstrate that this effect varies significantly based on inter-firm dependence, with interpersonal guanxi exhibiting a greater positive impact if such dependence is high.

This study enriches our understanding of interpersonal guanxi and of how companies can enhance the companies' business performance in an emerging market context.

The purpose of this paper is to examine Chinese consumers’ level of perception of genetically modified (GM) foods and the determinants of their willingness to pay (WTP) for Fad-3 GM lamb, a newly developed GM product.

Based on a randomized choice experiment involving 576 consumers in Beijing, the authors adopt a double-bounded contingent valuation method to estimate consumers’ WTP for Fad-3 GM lamb, as well as the causal impact of (randomized) product-information disclosure on it.

The econometric result indicates that the randomly disclosed product information describing details about Fad-3 GM lamb, the potential risks associated with the consumption of it, and the related governmental regulation policies raised consumers’ WTP by 6.2 yuan per Jin (or US$2/kilogram).

This paper provides new experimental evidence of the effect of product-information disclosure on consumers’ WTP for a newly developed GM food product.

As one of its major strategies, China has made a new plan to further expand High Standard Farmland (HSF) to all permanent basic farmland (80% of total farmland) for grain security over the next decade. Yet, what will be the impact of farmland infrastructure investment on agrifood systems? The paper aims to systematically evaluate the multiple effects (food security, economy, nutrition and environment) of expanding HSF construction under the context of the “Big Food vision” using an interdisciplinary model.

An interdisciplinary model – AgriFood Systems Model, which links the China CGE model to diet and carbon emission modules, is applied to assess the multiple effects of HSF construction on agrifood systems, such as food security and economic development, residents’ diet quality and carbon emissions. Several policy scenarios are designed to capture these effects of the past HSF investment based on counterfactual analysis and compare the effects of HSF future investment at the national level under the conditions of different land use policies – restricting to grain crops or allowing diversification (like vegetables, and fruit).

The investments in HSF offer a promising solution for addressing the challenges of food and nutrition security, economic development and environmental sustainability. Without HSF construction, grain production and self-sufficiency would decline significantly, while the agricultural and agrifood systems’ GDP would decrease. The future investment in the HSF construction will further increase both grain production and GDP, improve dietary quality and reduce carbon emissions. Compared with the policy of limiting HSF to planting grains, diversified planting can provide a more profitable economic return, improve dietary quality and reduce carbon emissions.

This study contributes to better informing the impact of land infrastructure expanding investment on the agrifood systems from multiple dimensions based on an interdisciplinary model. We suggest that the government consider applying diversified planting in the future HSF investment to meet nutritional and health demands, increase household income and reduce carbon emissions.

This study examines the impact of China’s trade, aid and foreign direct investment (FDI) on the economic growth of Africa.

Our study covered 41 countries in Africa, cutting across the western, eastern, central, southern and northern sub-regions. The study adopted the dynamic system generalized method of moments (SGMM), feasible generalized least squares (FGLS) and Dumitrescu–Hurlin Panel Granger causality techniques for estimations.

Overall, FDI, trade and aid from China have a nonlinear relationship with Africa’s economic growth. The findings reveal a key novelty in that the marginal effect on real per capita GDP increases when China’s FDI interacts with the manufacturing sector in Africa. These findings are robust to long-run estimations.

Given that we have examined the short-and long-run symbiotic effects of China’s FDI and Africa’s manufacturing sector and China’s aid and Africa’s manufacturing sector, more studies are warranted in this area, particularly to produce further empirical evidence of these findings. Moreover, future work could focus on investigating the country-specific effects of China’s trade, China’s FDI and China’s aid on real GDP per capita in each African country as our results reflect within-country elasticities.

This study provides new evidence on the impact of China’s trade, aid and FDI on the growth of African economies. To the best of our knowledge, this is the first study to empirically explore the long-run effects of China’s trade, FDI and aid on economic growth in African countries. This study also tests the claim of the displacement of Africa’s manufacturing industry by its Chinese counterparts.

This paper, with the tobacco industry as the background, establishes an indicator system for tobacco supply chain performance evaluation using the FAHP method.

Based on the relevant data of tobacco enterprises in Guangxi, the paper calculates the performance values of tobacco companies in various cities of Guangxi, and through the analysis of each indicator and the performance values of each city, the authors find that the improvement ability has a major impact on tobacco supply chain performance. Then, the paper establishes a system dynamics model to further demonstrate the impact of information digitalization on the performance of the tobacco supply chain in Guangxi, thus providing theoretical support for building digital tobacco logistics in Guangxi.

The findings of the study show that the performance of the tobacco supply chains in various cities of Guangxi is generally at the level of “Pass–Good,” which can barely meet the requirements of tobacco supply chain operation, but there is still plenty of room for improvement.

The authors show that digital and IT-based empowerment can maximize the performance of Guangxi's tobacco logistics performance.

With the function of reconstructing and promoting traditional industries in China, logistic service industry (LSI) still consumes a great deal of energy. The purpose of this paper is to empirically analyse the relationship between energy consumption of logistics and its influential factors in China, and through this, identify the most important factor and give a significant research of this factor afterwards.

Using a quantitative analysis of the industry composition of energy consumption and the structure of energy consumption in LSI, the serious condition of China's energy conservation of LSI was found. Correlated analysis and co‐integration analysis were adopted to identify how these factors affected the energy conservation of LSI and how to construct environmental logistics in China.

The paper found mileage traveled by train is the most important factor of energy consumption in LSI, while traveling miles of highway is the second. The former was negative correlation with the total of energy consumption while the latter was positive correlation.

Because of the deficiency of data in China, this research is based on the data of 30 years, which is not testified as long enough for this research. This would indicate that the conclusions of this paper are approximate values. A closer look should be taken at the effectiveness of some of the other factors suggested in the previous research on this topic.

The paper outlines ways to effectively construct environmental logistics in China which would promote the energy conservation and sustainable development of this country. Since the total consumption of energy in China accounts for a certain proportion of the world, this will benefit other countries as well.

This paper is one of the first of its kind to develop and empirically analyze the relationship between energy consumption of LSI and its influential factors in China. It uniquely contributes towards helping us find approaches to constructing China's environmental logistics and will have far‐reaching implications for other developing countries.