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Blockchain has the potential to facilitate a paradigm shift in the construction industry toward effectiveness, transparency and collaboration. However, there is currently a paucity of empirical evidence from real-world construction projects. This study aims to systematically review blockchain adoption barriers, investigate critical ones and propose corresponding solutions.

An integrated method was adopted in this research based on the technology–organization–environment (TOE) theory and fuzzy decision-making trial and evaluation laboratory (DEMATEL) approach. Blockchain adoption barriers were first presented using the TOE framework. Then, key barriers were identified based on the importance and causality analysis in the fuzzy DEMATEL. Several suggestions were proposed to facilitate blockchain diffusion from the standpoints of the government, the industry and construction organizations.

The results highlighted seven key barriers. Specifically, the construction industry is more concerned with environmental barriers, such as policy uncertainties (E2) and technology maturity (E3), while most technical barriers are causal factors, such as “interoperability (T4)” and “smart contracts' security (T2)”.

This study contributes to a better understanding of the problem associated with blockchain implementation and provides policymakers with recommendations.

Identified TOE barriers lay the groundwork for theoretical observations to comprehend the blockchain adoption problem. This research also applied the fuzzy method to blockchain adoption barrier analysis, which can reduce the uncertainty and subjectivity in expert evaluations with a small sample.

The purpose of this paper is to propose a fast, accurate and efficient algorithm for assessment of transient behavior of grounding grids buried in horizontal multilayered earth model considering soil ionization effect.

The purpose of this paper is to develop a numerical simulation method to calculate the lightning impulse response of the grounding grid buried in a horizontal multilayered earth model. The mathematical model about the hybrid method based on PI basic function belonging to time domain is proposed in the paper; the mode can precisely calculate the lightning current distribution and lightning impulse response to grounding grids buried in horizontal multilayered soil model considering soil ionization effect. To increase computing efficiency, quasi-static complex image method (QSCIM) and its time-domain Green’s function closed form are introduced in the model.

The hybrid model is rather stable, with the respect to the number of elements used and with excellent convergence rate. In addition, because this mathematical model belongs to the time domain algorithm, it is very powerful for the simulation of soil ionization caused by high amplitude lightning current.

To increase computing efficiency, QSCIM and its time domain Green's function closed form are introduced in the model.

The mathematical model about the hybrid method based on PI basic function can precisely calculate the lightning current distribution and lightning impulse response to grounding grids buried in horizontal multilayered soil model considering the soil ionization effect.

Considering the soil ionization effect, the simulation calculation of lightning impulse response of substation grounding grid buried in the actual horizontal multilayered earth can effectively support the scientific and efficient design of lightning protection performance of substation grounding grid.

The hybrid model in time domain is originally developed by the authors and used to precisely calculate the lightning current distribution and lightning impulse response to grounding grids buried in horizontal multilayered soil model considering soil ionization effect. It is simple and very efficient and can easily be extended to arbitrary grounding configurations.

Laser powder bed fusion (LPBF) in-situ alloying is a recently developed technology that provides a facile approach to optimizing the microstructural and compositional characteristics of the components for high performance goals. However, the complex mass and heat transfer behavior of the molten pool results in an inhomogeneous composition distribution within the samples fabricated by LPBF in-situ alloying. The study aims to investigate the heat and mass transfer behavior of an in-situ alloyed molten pool by developing a three-dimensional transient thermal-flow model that couples the metallurgical behavior of the alloy, thereby revealing the formation mechanism of composition inhomogeneity.

A multispecies multiphase computational fluid dynamic model was developed with thermodynamic factors derived from the phase diagram of the selected alloy system. The characteristics of the Al/Cu powder bed in-situ alloying process were investigated as a benchmark. The metallurgical behaviors including powder melting, thermal-flow, element transfer and solidification were investigated.

The Peclet number indicates that the mass transfer in the molten pool is dominated by convection. The large variation in material properties and temperature results in the presence of partially melted Cu-powder and pre-solidified particles in the molten pool, which further hinder the convection mixing. The study of simulation and experiment indicates that optimizing the laser energy input is beneficial for element homogenization. The effective time and driving force of the convection stirring can be improved by increasing the volume energy density.

This study provides an in-depth understanding of the formation mechanism of composition inhomogeneity in alloy fabricated by LPBF in-situ alloying.

The purpose of this paper is to determine the failure reasons and failure mechanism of the commercially pure titanium air conditioning condenser.

In this paper, chemical analysis, metallographic observation, visual examination and scanning electron microscope examination, corrosion products analysis and working conditions analysis were adopted for determining the reasons for the failure of the condenser.

The results indicated that TA2 titanium pipe perforation failure is caused by the synergistic effect of crevice corrosion and deposit corrosion. The corrosion processes can be divided into three steps.

This research is an originality study on the failure case of a commercially pure titanium air conditioning condenser. This study makes up for the shortage of titanium alloy failure cases and also gives the result of the failure reason and failure mechanism for titanium, which has an engineering significance.

The Chemical Integrated Information Service Network (Chl2Net) is a comprehensive information service system which includes chemical, technical, economic, market, news and management information based on computer and modern communication technology, and built by the China National Chemical Information Centre (CNCIC). This system provides varied services for users both at home and abroad through an online service, a hotline call service, a consulting service and publishing service.

Low-alloy structural steels (LASS) face severe microbiologically influenced corrosion (MIC) in their service environments. To mitigate this issue, Cu is often used as an alloying element owing to its intrinsic antimicrobial activity. However, the antibacterial performance and biofilm resistance of Cu-containing LASS (Cu-LASS) are still unclear. This study aims to analyze the effect of Cu addition to 420 MP LASS on its MIC by the Pseudomonas aeruginosa biofilm.

Scanning electron microscope, confocal laser scanning microscope and X-ray photoelectron spectroscopy were used to analyze the surface morphology and composition of corrosion products. The antibacterial activities of Cu-LASS were analyzed by the spread-plate method. In addition, electrochemical analysis was conducted to characterize the corrosion behavior of the produced alloy.

Bacterial analysis and morphological observation confirmed a reduced sessile cell count and inactivation of the P. aeruginosa biofilm on the surface of Cu-LASS coupons. Electrochemical measurements showed that Cu-LASS exhibited large polarization and charge-transfer resistances, which indicated excellent MIC resistance. This significantly enhanced resistance to MIC could be explained by the synergistic effect of released Cu²⁺ from the Cu-LASS surface and immediate contact to Cu-rich phase in the surface and the release of Cu²⁺ ions from the Cu-LASS surface.

The effect of Cu addition on the MIC resistance and antibacterial performance of LASS is seldom reported. It is necessary to investigate the corrosion resistance of Cu-LASS and clarify its antibacterial mechanism. This paper fulfills this need.

To study the corrosion behavior of pipeline steel in coastal areas, a tidal seawater macro-cell corrosion device was built using a cycle soaking tank and a macro-cell corrosion facility to simulate the corrosion behavior of pipeline steel in a simulated coastal environment (dry and wet alternations during seawater-soil corrosion macro-cell processes).

The corrosion behaviors were studied via the weight loss method, electrochemical methods and morphological observations on corrosion.

The results show that during the initial stage of tidal seawater/soil macro-cell corrosion process of the X65 steel, the working electrode on the seawater side is the anode of the macro-battery. As corrosion progresses, the anode and the cathode of the macro-battery become inverted. As the area ratio and the dry – wet ratio increase, the time of anode and cathode inversion shortens. Galvanic current density decreases as the dry – wet ratio increases and increases as the area ratio increases. The corrosion process of macro-cell is affected by the reversal of anode and cathode. After the reversal of anode and cathode, the corrosion rate is mainly controlled by dry – wet alternating corrosion.

The corrosion behavior of a pipeline steel in a coastal environment was studied using a tidal seawater macro-cell corrosion device. The synergism effect between the tidal seawater and seawater-soil macro-cell on corrosion behavior was clarified.

The purpose of this paper is to investigate how international R & D alliances are formed during industry transition from the point of view of the local Chinese partner.

Review of industry data provided by Chinese Statistical Office coupled with four in-depth case studies.

The nature of the technology, the characteristics of partners and the previous cooperation experience between partners are significantly related to the R & D alliance formation. The research also suggests that during this fast-growing transition period, Chinese local firms preferred non-equity contractual agreements over equity joint venture such as R & D alliance modes, and Chinese local firms favoured American and European multinational corporations (MNCs) as their alliance partners over MNCs from other countries, including the highly developed Japan and Korea.

Single-industry focus (telecommunications), and anonymization of cases because of confidentiality of case firms. Single-country focus (China).

Firms in China and other emerging countries can improve their technological capability (TC) by choice to facilitate future alliance formation to access and learn the latest technology from their alliance partners, especially during the transition period of an industry and when mature and emerging technologies co-exist.

This paper refines alliance theory by focusing on an industry in transition and analyses formation decision factors from the point of view of the smaller domestic partner – usually studies do not differentiate as to industry maturity and inequality between partners.

In line with the recent development of flip-chip reliability and underfill process, this paper aims to comprehensively investigate the effect of different hourglass shape solder joint on underfill encapsulation process by mean of experimental and numerical method.

Lattice Boltzmann method (LBM) numerical was used for the three-dimensional simulation of underfill process. The effects of ball grid arrays (BGA) encapsulation process in terms of filling time of the fluid were investigated. Experiments were then carried out to validate the simulation results.

Hourglass shape solder joint has shown the shortest filling time for underfill process compared to truncated sphere. The underfill flow obtained from both simulation and experimental results are found to be in good agreement for the BGA model studied. The findings have also shown that the filling time of Hourglass 2 with parabolic shape gives faster filling time compared to the Hourglass 1 with hemisphere angle due to bigger cross-sectional area of void between the solder joints.

This paper provides reliable insights to the effect of hourglass shape BGA on the encapsulation process that will benefit future development of BGA packages.

LBM numerical method was implemented in this research to study the flow behaviour of an encapsulation process in term of filling time of hourglass shape BGA. To date, no research has been found to simulate the hourglass shape BGA using LBM.

When the power generator faces uncertain and independent electricity spot price and renewable energy source supply, two different conditions need to be considered: the distributions of renewable energy source electricity and electricity spot price are independent or dependent. The purpose of this paper is to explore the capacity investment strategy under volatile electricity spot price when renewable energy penetration rate is low, taking into account these two conditions.

The authors design a capacity investment model under dual uncertainties and consider how to optimize the investment capacity in order to maximize profit under two different conditions.

The authors find that when renewable energy supply fluctuation is unrelated to spot electricity price fluctuation, the renewable energy power profitability is determined by the average cost of spot electricity price and equivalent cost. When renewable energy supply fluctuation is related to spot electricity price fluctuation, the renewable energy power profitability is determined by the market value and the construction and maintenance cost.

Faced with the conflict of the renewable energy supply, the authors need to understand how to plan the generation capacity with intermittent renewable sources. The result helps renewable energy become competitive in the electricity market under loose regulations.

The authors compare two capacity investment strategies that the renewable energy supply fluctuation is related and unrelated to spot electricity price.