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In large-scale monitoring systems, sensors in different locations are deployed to collect massive useful time-series data, which can help in real-time data analytics and its related applications. However, affected by hardware device itself, sensor nodes often fail to work, resulting in a common phenomenon that the collected data are incomplete. The purpose of this study is to predict and recover the missing data in sensor networks.

Considering the spatio-temporal correlation of large-scale sensor data, this paper proposes a data recover model in sensor networks based on a deep learning method, i.e. deep belief network (DBN). Specifically, when one sensor fails, the historical time-series data of its own and the real-time data from surrounding sensor nodes, which have high similarity with a failure observed using the proposed similarity filter, are collected first. Then, the high-level feature representation of these spatio-temporal correlation data is extracted by DBN. Moreover, to determine the structure of a DBN model, a reconstruction error-based algorithm is proposed. Finally, the missing data are predicted based on these features by a single-layer neural network.

This paper collects a noise data set from an airport monitoring system for experiments. Various comparative experiments show that the proposed algorithms are effective. The proposed data recovery model is compared with several other classical models, and the experimental results prove that the deep learning-based model can not only get a better prediction accuracy but also get a better performance in training time and model robustness.

A deep learning method is investigated in data recovery task, and it proved to be effective compared with other previous methods. This might provide a practical experience in the application of a deep learning method.

The purpose of the paper is to show that how a contactless power transmission system via electromagnetic (EM) resonantly coupling power transmission (RCPT) technology may be analyzed in-depth by using a detailed T-type two-port network model with leakage inductance variable.

Through the introduction of coupling coefficient and quality factor, the influence of different physical parameters on the system performance is taken into consideration and validated by power transmission experiment.

It is shown that system performance is mainly subject to coupling coefficient and quality factor from the two-port network model in this paper. Moreover, there are three working status of dynamic transmission, which are over coupling, critical coupling and under coupling.

Two-port network model applied to practical RCPT system design considering impedance loss on resonators, etc.

The aim of this paper is to provide a narrative review of previous research on tourism demand modelling and forecasting and potential future developments.

A narrative approach is taken in this review of the current body of knowledge.

Significant methodological advancements in tourism demand modelling and forecasting over the past two decades are identified.

The distinct characteristics of the various methods applied in the field are summarised and a research agenda for future investigations is proposed.

本文旨在对先前关于旅游需求建模和预测的研究进行叙述性回顾并对未来潜在发展进行展望。

本文采用叙述性回顾方法对当前知识体系进行了评论。

本文确认了过去二十年旅游需求建模和预测方法论方面的重要进展。

本文总结了该领域应用的各种方法的独特特征, 并对未来研究提出了建议。

El objetivo de este documento es ofrecer una revisión narrativa de la investigación previa sobre modelización y previsión de la demanda turística y los posibles desarrollos futuros.

En esta revisión del marco actual de conocimientos sobre modelización y previsión de la demanda turística y los posibles desarrollos futuros,se adopta un enfoque narrativo.

Se identifican avances metodológicos significativos en la modelización y previsión de la demanda turística en las dos últimas décadas.

Se resumen las características propias de los diversos métodos aplicados en este campo y se propone una agenda de investigación para futuros trabajos.

The implementation of sustainable supply chain management (SCM) calls for an acknowledgement of uncertainty inherent in complex environment. Confucianist society forms social networks in Confucianist society, called guanxi networks, influence economic behaviours and business practices in the workplace. The purpose of this study is to explore how these social networks influence the implementation of sustainable SCM. In doing so, this study aims to critically investigate the constructs of guanxi networks, their impact on flow of supply chain capital and how this leverages the implementation of sustainable SCM.

Two systematic literature reviews are conducted to understand the constructs of social networks in Confucianist culture and their impacts on the flow of supply chain capitals. The reviews also analyse evidence related to the economic, social and environmental practices to reveal the current state of the literature and research gaps. Propositions and a framework are developed to support future research in this area.

The constructs of ganqing, renqing, xinren and mianzi in guanxi networks have expanded the contexts of social networks in Western literature. Guanxi networks increase the flow of supply chain capital and generate trust between players, thus enhancing capabilities to implement sustainable SCM. Guanxi networks also create the mechanism of network governance with which to increase sustainable SCM implementation under the institutional logics of sustainability.

The conceptual framework and justification are based on the reviews of current studies in the field. Future empirical study is encouraged to test the propositions, both in Confucianist culture and other countries with culture of social networks.

Social networks are socially constructed concepts. The constructs of guanxi networks revealed in this study have developed the knowledge of Western-based social network theory. Besides, arguments from a social network perspective provide an alternative answer to explain increased behavioural commitment and companies’ investment in sustainable SCM. This study helps practitioners understand the logic of this social norm and to use it to maximise their operation outputs, including sustainable SCM implementation.

This study examines principal rotation in China to gain empirical insights from the policy analysis and succession strategies that principals employ to gain internal and external support in their new schools.

We employed document analysis and a case study approach. Interviews were conducted with officials in 5 local educational agencies and 40 principals from 5 different regions who were undergoing rotation. Thematic analysis was used to identify common patterns and themes in the interview responses.

We explored how the principal-rotation policy was implemented, including the goals, standards, targeted principals, tools and other aspects of the policy in China. The study revealed the challenges faced by the rotated principals and their succession strategies.

Our study contributes to the field of educational leadership by shedding light on the implementation and impact of principal rotation in mainland China.

The tikog handicraft industry in Basey, province of Samar in the Philippines, was heavily devastated by super typhoon Haiyan in November 2013. More than five years after the disaster, very few studies have been published regarding the status of this industry. Thus, this paper aims to examine the roles of men and women farmers, weavers, converters and other chain actors of the Tikog Value Chain Industry in Basey and presents the status of the industry in terms of (a) operations, (b) performance and contribution to the economy, (c) capacity (materials, product and people), (d) market and (e) its current challenges in a post-disaster context.

For this case study, data were gathered through desk research and field works. The data were thematically analyzed using elements of a value chain analysis to provide insights and to help develop strategies to improve women’s contributions in developing the tikog handicraft industry.

Among the structures in the industry are associations comprising of formal and informal groups of tikog farmers, weavers, converters and traders. About 2,000 families in Basey are engaged in the tikog industry. This generates an estimated additional family income from PHP 4,200.00 (USD84.00) – PHP 18,000.00 (USD360.00)/year. Supply of raw materials is not only hampered by the depleting natural resources but also by the availability of drying facilities. Weavers continue to buy from Leyte suppliers due to challenges in drying tikog grasses. The author strongly argues that there is a need to increase capacity building opportunities for those involved in tikog to avoid stunted growth of the industry.

Aside from being a survivor himself, the author directly worked with the men, women and communities involved in this study. This highlights the ability of this research to realistically reflect the current knowledge, practices and attitudes of actors involved in the tikog handicraft industry in Basey, Philippines.

A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions.

A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions. The structures of the intermediate and final products were characterized by FT-IR (Fourier transform infrared spectroscopy analysis), ¹H-NMR (proton nuclear magnetic resonance spectroscopy) methods. The thermal performance of surfactants was analyzed using thermogravimetric analysis (TGA). The thermogravimetric results showed that the sulfate-based Gemini surfactants had good heat resistance (the thermal decomposition temperature of which was in the range of 140∼170?). The Krafft point, surface tension, foaming, Hydrophile–Lipophile Balance Number (HLB), emulsifying, wetting, and lime-soap dispersing performance were measured by visual observation, hanging drop method, aqueous surfactant solution method and Borghetti–Bergman method, respectively. The results have shown that all the sulfate-based Gemini surfactants had good water solubility and lime-soap dispersing ability. When spacer group was -(CH2)2-, with the increase of the carbon chain length from C12 to C14, the micellar concentration critical micelle concentration and surface tension (CMC) gradually increased from 8.25 × 10^–4 mol/L to 8.75 × 10^–4 mol/L and 27.5 mN/m to 30.9 mN/m, respectively. Also, the sulfate-based Gemini surfactants with the different length of the spacer group had a different effect on their performance on foaming properties and foam properties, HLB and emulsifying ability and wetting ability.

In view of the important role of the spacer group and the general use of anionic surfactants in oil fields, this article considers the preparation of a series of sulfate-based Gemini surfactants by changing the spacer group and the chain length of the hydrophobic group and evaluating their surface activity, and finally its Kraffi, on the foam properties, HLB value, emulsifying performance, lime soap dispersing ability etc.

Sulfate-based Gemini surfactants have broad application prospects in the fields of oil and gas exploitation, environmental protection, chemistry and daily chemical industry and so on.