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This paper aims to reduce and eliminate the abnormal peaks which, because of the reflection in the process of laser detection, make it easier to proceed with further analysis.

To solve the above problem, an abnormal data correction algorithm based on histogram, K-Means clustering and improved robust locally weighted scatter plot smoothing (LOWESS) is put forward. The proposed algorithm does section leveling for shear plant first and then applies histogram to define the abnormal fluctuation data between the neighboring points and utilizes a K-Means clustering to eliminate the abnormal data. After that, the improved robust LOWESS method, which is based on Euclidean distance, is used to remove the noise interference and finally obtain the waveform characteristics for next data processing.

The experiment result of liner tool mark laser test data correction demonstrates the accuracy and reliability of the proposed algorithm.

The study enables the following points: the detection signal automatic leveling; abnormal data identification and demarcation using K-Means clustering and histogram; and data smoothing using LOWESS.

This paper aims to focus on achieving triple-shape memory effect (triple-SME) of a commercial poly (ethylene terephthalate) (PET) film with the thickness of 100 µm.

The thermal characteristics and microstructure of PET film were characterized by differential scanning calorimetry, thermogravimetric analysis and wide-angle X-ray diffraction analysis. The dual-shape memory effect (dual-SME) of the PET film was then systematically investigated, and based on that, triple-SME in thin PET film was achieved.

Investigation of the dual-SME in PET film revealed the difference between recovery temperature and programming temperature reduced with increasing programming temperature. An obvious intermediate shape shifting between the original and final programmed shape was observed during shape recovery in triple-shape memory behaviors.

Compared with dual-SME in polymer, relatively less work has been done on multi-SME in polymer, especially in thin polymer film. In this study, triple-SME in a PET film was investigated based on the results of dual-SME of the film. The main implication of the study is on how to achieve a watermark between the final programmed pattern and the original pattern, for the application of shape memory polymer in anti-counterfeiting label.

Dual- and triple-SMEs were achieved in a PET film that is only 100 µm in thickness, and the underlying mechanism for the difference between programming temperature and recovery temperature was discussed. For the novel application of triple-SME in anti-counterfeit label, the watermark during shape recovery in triple-SME can effectively prevent duplication.

The purpose of this paper is to explore and compare haze-related content between traditional and social media in China by applying agenda-setting theory and the extended parallel process model (EPPM). Specifically, this paper examines the correlation between the two forms of media in terms of the ranking of the attributes of haze (i.e. the EPPM components) and the interrelationships among the attributes.

Content analysis and semantic network analysis were employed to address the research aims.

The results revealed that more than half of the total messages on both types of media reflected the EPPM components, either threat or efficacy information. However, the imbalance between the threat and efficacy information was more prominent in the haze-related content presented in the People’s Daily than it was on Weibo. In addition, the results from a Spearman’s rank-order correlation and a quadratic assignment procedure (QAP) indicated that there was no significant correlation between the People’s Daily and Weibo in terms of the rankings of the attributes of haze (i.e. the EPPM components) or the interrelationships among the attributes.

This study is the first to apply a theoretical approach to examine and compare the nature of haze-related messages on traditional and social media.

The paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, this paper aims to propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system to distribute to solve the problem of control and communication failure at the same time.

In the paper, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the air-ground integrated wireless ad hoc network-integrated system.

The results show that the integrated system has good robustness and fault tolerance performance indicators for flight control and wireless signal transmission when confronted with external disturbances, internal actuator failures and wireless network associated failures and the flight control curve of the quadrotor unmanned aerial vehicle (UAV) is generally smooth and stable, even if it encounters external disturbances and actuator failures, its fault tolerance performance is very good. Then in the range of 400–800 m wireless communication distance, the success rate of wireless signal loop transmission is stable at 80%–100% and the performance is at least relatively improved by 158.823%.

This paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, based on the robust fault-tolerant control algorithm, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system and through the Riccati equation and linear matrix inequation method, the designed distributed robust H_∞ adaptive fault-tolerant controller further optimizes the fault suppression factor γ, so as to break through the limitation of only one Lyapunov matrix for different fault modes to distribute to solve the problem of control and communication failure at the same time.

The category of ‘child’ is often presumed to be underpinned by ‘natural’ biological differences from the category of ‘adult’, and the category of ‘family’ is open to similar ‘naturalising’ and universalizing tendencies. Challenging this view has been a central tenet of the New Social Studies of Childhood, arguing instead that ‘child’ and ‘childhood’ are socially constructed, and highlighting children’s agency in shaping their social worlds. More complex frameworks have since emerged, whether concerning the need for a relational ontology of ‘child’, or for a recognition of the diversity of childhoods and families globally. Here we extend the debate to engage with the problematic of the very nature of ‘categories’ themselves, to explore how categorical thinking varies across, and is embedded within, linguistic, historical and philosophical processes and world views. Drawing on the examples of the categories of ‘child’ in China, and ‘family’ in Senegal, West Africa, we consider aspects of fluidity in their indigenous linguistic framing, and how their translation into European terms may fail to fully capture their meanings, which may ‘slip away’ in the process. Such ‘gaps’ between divergent linguistic framings include underlying world views, and assumptions about what it means to be human, raising issues of individuality, relationality and connectedness. Through this discussion we raise new questions concerning the processes of categorical thinking in relation to ‘child’ and ‘family’, calling for cautious consideration of what may be ‘unthought’ in these categories as they feature in much of contemporary childhood and family studies.

This study aims to explore the feasibility of adding Si₃N₄ nanoparticles to Sn58Bi and provides a theoretical basis for designing and applying new lead-free solder materials for the electronic packaging industry.

In this paper, Sn58Bi-xSi₃N₄ (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0 Wt.%) was prepared for bonding Cu substrate, and the changes in thermal properties, wettability, microstructure, interfacial intermetallic compound and mechanical properties of the composite solder were systematically studied.

The experiment results demonstrate that including Si₃N₄ nanoparticles does not significantly impact the melting point of Sn58Bi solder, and the undercooling degree of solder only fluctuates slightly. The molten solder spreading area reached a maximum of 96.17 mm², raised by 19.41% relative to those without Si₃N₄, and the wetting angle was the smallest at 0.6 Wt.% of Si₃N₄, with a minimum value of 8.35°. When the Si₃N₄ nanoparticles reach 0.6 Wt.%, the solder joint microstructure is significantly refined. Appropriately adding Si₃N₄ nanoparticles will slightly increase the solder alloy hardness. When the concentration of Si₃N₄ reaches 0.6 Wt.%, the joints shear strength reached 45.30 MPa, representing a 49.85% increase compared to those without additives. A thorough examination indicates that legitimately incorporating Si₃N₄ nanoparticles into Sn58Bi solder can enhance its synthetical performance, and 0.6 Wt.% is the best addition amount in our test setting.

In this paper, Si₃N₄ nanoparticles were incorporated into Sn58Bi solder, and the effects of different contents of Si₃N₄ nanoparticles on Sn58Bi solder were investigated from various aspects.

With a focus on undergraduate music major students in China, the study sought to examine how higher music education institutions prepare professional knowledge, professional skills and soft skills in relevance to music students' employability.

The quantitative survey engaged 359 music students from five music institutions in Western China to report their perceptions toward music curriculum related to employability. The current study examined whether their perception varied based on their gender, location, school, educational background and professional option purpose.

Perception differences in the music curriculum were observed across gender, schools, educational background and professional option purpose. School differences were the most significant among all five factors, followed by professional option purpose, educational background and gender. The location difference was insignificant among the five factors. There were insufficient opportunities for community and industrial engagement in higher music education.

The current study provides an insight into the higher music education curriculum for employability preparation in current China. This is one of the limited empirical studies in Western China to investigate music students' perceptions of professional knowledge and skills and the soft skill line with employability. The findings can serve as a reference for prospective employees in the music industry, policymaking and curriculum design and future research.

Drawing upon the communicative ecology theory (CET), this study aims to identify the potential precursors of social media health information seeking intentions (ISI) and examine their effects on health information re-sharing behaviors and PHH during coronavirus (COVID-19) pandemic.

The data is collected through an online survey conducted in two different universities situated in highly COVID-19-affected cities – Wuhan and Zhengzhou, China. The valid data consists of 230 useful responses from WeChat users and to analyze the final data set structural equation modeling (SEM) is used.

The results indicate that perceived health information credibility (PIC), trust on the medium (TRM) and peer influence (PI) significantly affect health ISI which further affects health information re-sharing behaviors (IRB) and personal health-care habits (PHH). Besides, the results also identify that PI has a direct, positive and significant effect on health IRB via social media during the COVID-19 pandemic.

This study investigates the health information intentional behavior precursors and their consequences via WeChat (taken as social media platform) during COVID-19 pandemic. Future studies may conduct research by examining online information behaviors on other social media platforms – Twitter, WhatsApp, Facebook, etc. – in health emergency situations.

The health information producers and providers have to deal with communicative ecology sentiments elegantly in emergency situations such as during the COVID-19 pandemic. They need to do collective efforts by introducing new tools or social apps which deal with valuable, reliable and accurate health content and information generated by the pandemic experts and health professionals. In such a way, the social apps and tools (Information providers) will act as mediators between the health professionals (Information producers) and general social media users (information seekers). Such initiatives will ultimately bring forth positive effect on individuals’ PHH as a whole within a network, community, environment or nations during a health emergency – COVID-19 pandemic.

This research is one of the first studies to examine the potential precursors of social media health ISIs and their resultant effects on individual’s health IRB and PHH during the COVID-19 pandemic. As currently it is noticed, an incredible upsurge of health information via social media has intense impacts on personal health-care research and practice, particularly during health emergency situations such as COVID-19 pandemic conditions.

This paper aims to use cone-beam computed tomography (CBCT) and computer-aided design/3D printing technology to design and fabricate a drill guide template for access cavity preparation of permanent molars, and conduct a preliminary evaluation of its effectiveness.

CBCT scans were performed on two permanent maxillary first molars extracted due to periodontitis. Based on the scans, guide templates of access cavities were designed. The angle of the guiding cylinders was determined based on the direction of the long axis of the tooth. A 3D resin printer with high resolution was used to print the guide templates. The printed guide templates were used by a dentist with specialized clinical experience to perform access cavity preparation in a dental simulator. Then the prepared access cavities were scanned again by CBCT, and scan data were compared to the design data.

The 3D printed drill guide template had a close fit with the extracted tooth fit. The access cavity prepared using the guide template enabled the removal of the pulp chamber roof, and formed a straight-line access. Points were selected for measurement at regularly spaced intervals of 0.5 mm along the side wall of the access cavity. The mean deviation between the actual access cavities of the two permanent maxillary first molars and the designed cavities was less than 0.1 mm, with a maximum deviation of about 0.5 mm, showing a good conformance between the actual cavity and the designed cavity.

A drill guide template was designed and fabricated by 3D printing technology, which easily guided burs to complete the access cavity preparation work forming an ideal cavity shape with satisfying accuracy, and thus may reduce the complications during pulp chamber entry.

The construction sector has significantly evolved in recent decades, in parallel with a huge increase in the amount of data generated and exchanged in any construction project. These data need to be managed in order to complete a successful project in terms of quality, cost and schedule in the the context of a safe project environment while appropriately organising many construction documents.

However, the origin of these data is very diverse, mainly due to the sector’s characteristics. Moreover, these data are affected by uncertainty, complexity and diversity due to the imprecise nature of the many factors involved in construction projects. As a result, construction project data are associated with large, irregular and scattered datasets.

The objective of this chapter is to introduce an approach based on a fuzzy multi-dimensional model and on line analytical processing (OLAP) operations in order to manage construction data and support the decision-making process based on previous experiences. On one hand, the proposal allows for the integration of data in a common repository which is accessible to users along the whole project’s life cycle. On the other hand, it allows for the establishment of more flexible structures for representing the data of the main tasks in the construction project management domain. The incorporation of this fuzzy framework allows for the management of imprecision in construction data and provides easy and intuitive access to users so that they can make more reliable decisions.