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At present, piezoelectric impedance technology has been used in the study of wood damage monitoring. However, little effort has been made in the research on the application of piezoelectric impedance system to monitor the change of wood moisture content (MC). The monitoring method of wood MC is used by piezoelectric impedance technique in this study.

One piezoceramic transducer is bonded to the surface of wood specimens. The MC of the wood specimens increases gradually from 0% to 60% with 10% increments; the mechanical impedance of the wood specimen will change, and the change in the mechanical impedance of the structure is reflected by monitoring the change in the electrical impedance of lead zirconate titanate. Therefore, this paper investigates the relationship between wood MC change and piezoelectric impedance change to verify the feasibility of the piezoelectric impedance method for monitoring wood MC change.

The experiment verified that the real part of impedance of the wood increased with the increase of wood MC. Besides, the damage index root mean square deviation is introduced to quantify the damage degree of wood under different MC. At the same time, the feasibility and validity of this experiment were verified from the side by finite element simulation. Finally, MC monitoring by piezoelectric impedance technique is feasible.

To the best of the authors’ knowledge, this work is the first to apply piezoelectric ceramics to the monitoring of wood MC, which provides a theoretical basis for the follow-up study of a wide range of wood components and even wood structure MC changes.

In today's digital and post-pandemic era, construction teams can span their boundary to obtain important resources and support in computer-mediated ways. However, the benefits of computer-mediated team boundary spanning (TBS) are mostly assumed. Empirical evidence for these benefits is in lack. Thus, this study attempts to investigate the influence of computer-mediated (instant messaging in this study) TBS on construction project performance and the underlying mechanism.

From the multiteam system (MTS) perspective, this study employs the input-process-outcome (IPO) framework and coordination theory to explore the influence of instant messaging-based team boundary spanning (IMTBS) on construction project coordination processes and project performance. A theoretical model is built and validated with a survey involving 206 construction projects.

Results show that IMTBS positively affects knowledge integration and project coordination, but negatively affects project commitment. The positive link between IMTBS and project performance is attributable to knowledge integration and project coordination. Further, project commitment is also found to negatively mediate the relationship between IMTBS and construction project performance.

To the best of the authors’ knowledge, this study is the first to empirically investigate the influence of TBS on construction project performance. As such, this study contributes to the literature on TBS in the construction field. In addition, the findings of this study unveil the double-edged characteristic of IMTBS, which should attract managers' attention. This also indicates that the form of TBS is a significant determinant of its effectiveness, which should attract scholars' attention in the future.

The purpose of this study is to extract the real requirements of the owner (or users) for the construction project in the operation and maintenance stage completely and accurately and carry out the construction based on the requirements, to make the project status and operation and maintenance requirements (RO&M) consistent after delivered.

This study creatively proposes the operation and maintenance functions deployment (OMFD) under RO&M. In addition, the OPAR (naming is made up of the initials of owners, project, analysis and result) model is constructed to fully identify the requirements of both owners and projects. In this study, three typical construction projects are taken as examples to calculate the correlation strength between project characteristics (PC) and operation and maintenance requirements through the Apriori algorithm, and order parameters are obtained from the cost chain.

This study found that there are significant differences in the correlation strength between 11 types of RO&M and PC, in which the “cost of types” (TC) correlation of residential housing and factory buildings is the largest, while the largest correlation demand of commercial buildings is “safety of types” (TS) and “system” (S). Simultaneously, through the calculation of order parameters, the most influential factors on project characteristics are obtained.

This study could effectively help the owner (or users) to check whether the delivered project fully satisfy their real requirements and also extract the key technical points to realize RO&M, which can guide the accurate construction of the same type of projects.

This research establishes OPAR model to accurately identify the requirements of the project in the operation and maintenance stage and establishes the association rules between the requirements and the construction scheme, which is helpful for the project to construct under the expected requirements.

Guided by social exchange theory and signaling theory, this chapter investigates the relationship between individual perceptions of high-performance work systems (HPWS), union instrumentality, and employees’ turnover intention. The results obtained from a multilevel and multisource sample of more than 1,300 employees in 37 multinational corporation based in China show that, in contrast to our hypothesis, union instrumentality is not directly related to turnover intention; rather, the results from the post hoc mediation analysis show that union instrumentality is indirectly and negatively related to turnover intention through affective organizational commitment. Consistent with our hypothesis, the results of our analysis show that union instrumentality serves as an important contingent factor in the relationship between HPWS and employee turnover intention. The relationship between HPWS and turnover intention becomes positive when employee union instrumentality is low.

This paper aims to successfully synthesize three-dimensional spindle-like Au functionalized Co₃O₄-ZnO nanocomposites; characterize the structure, morphology and surface chemical properties of the products; study the effect of Au NPs doping concentration, operating temperature different gas to, sensing properties; and introduce an attractive gas sensor for acetone detection.

Au NPs functionalized Co₃O₄-ZnO nanocomposite was prepared by coprecipitation and impregnation methods; the structure and surface chemical property of the products were characterized by XRD, SEM, TEM, UV-Vis, BET and XPS. The sensing ability of Au@Co₃O₄-ZnO for acetone and mechanism was analyzed systematically.

The results of gas sensing tests show that the unique component structure, Schottky junction and catalytic effect of Au functionalization make it have low operating temperature, excellent selectivity, high response (10 ppm, 56) and rapid response recovery time.

All the characterization and test data of the prepared materials are provided in this paper and reveals the gas sensing mechanism of the gas sensor.

The detection limit is 2.92–100 ppb acetone. It is promising to be applied in low-power, micro detection and miniature acetone gas sensors.

The gas sensor prepared has a lower working temperature and low detection limit, so it has promising application prospects in low-concentration acetone detection and early warning.

The unique component structure, Schottky junction and catalytic effect of Au functionalization Co₃O₄-ZnO make it have low operating temperature, excellent selectivity and rapid response recovery time.

The purpose of this paper is to analyze energy performance of the multi-storey buildings built in the city of Tlemcen between 1872 and 2016.

A diagnosis based on a bottom-up methodology, using statistical techniques and engineering, has been developed and applied. To do this, demand condition analysis was conducted using a data collection survey on a sample of 100 case studies. Physical characteristics of the buildings have been determined through the archetype by period. This serves to define the strengths and weaknesses of buildings as energy consumers.

The obtained results showed that dwellings built between 1872 and 1920 offer better energy performance with a consumption index close to 130kWh/m²/year and this compared to the five periods considered. For dwellings built between 1974 and 1989, energy consumption is higher with an index approaching 300kWh/m²/year, thus qualifying the buildings of this period as energy intensive.

A database is established to collect physical information on the existing housing stock and thus allow their classification vis-à-vis of the energy label. This study is part of a research project aimed at evaluating and determining optimal measures for energy rehabilitation of multi-family buildings in Tlemcen. Thermal rehabilitation solutions are proposed using thermal simulations, in the following studies, to improve thermal performance of existing buildings. This study constitutes the first step of a roadmap applicable to other cities constituting climatic zones in Algeria. This helps to enrich the Algerian thermal regulation in thermal rehabilitation of existing residential buildings and conception of new ones, in urban areas with a similar climate.

The purpose of this paper is to improve the corrosion resistance of the 6061-Al alloy as the battery pack material for electric vehicles, and the nano-SiC/MAO composite coating was prepared.

The corrosion resistance of coatings was evaluated by the global electrochemical test, and the local electrochemical impedance spectroscopy (LEIS) was used to study the local corrosion mechanism. The laser confocal microscope, scanning electron microscope and X-ray diffractometer (XRD) were used to characterise coatings.

Results showed that the impedance of nano-SiC/MAO coating was 1–2 times higher than MAO coating, and the main corrosion product was Al(OH)₃. LEIS results showed that the impedance of the nano-SiC/MAO coating was two times higher than the MAO coating. The defective SiC/Micro-arc oxidation coating still had high corrosion resistance compared to the MAO coating.

The physical model of the local corrosion mechanism for SiC/MAO composite coating in “cavity-fracture collapse” mode was proposed.