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This study aims to introduce the hybrid finite element (FE) – meshfree method and multiscale variational principle into the traditional mixed FE formulation, leading to a stable mixed formulation for incompressible linear elasticity which circumvents the need to satisfy inf-sup condition.

Using the hybrid FE–meshfree method, the displacement and pressure are interpolated conveniently with the same order so that a continuous pressure field can be obtained with low-order elements. The multiscale variational principle is then introduced into the Galerkin form to obtain stable and convergent results.

The present method is capable of overcoming volume locking and does not exhibit unphysical oscillations near the incompressible limit. Moreover, there are no extra unknowns introduced in the present method because the fine-scale unknowns are eliminated using the static condensation technique, and there is no need to evaluate any user-defined stability parameter as the classical stabilization methods do. The shape functions constructed in the present model possess continuous derivatives at nodes, which gives a continuous and more precise stress field with no need of an additional smooth process. The shape functions in the present model also possess the Kronecker delta property, so that it is convenient to impose essential boundary conditions.

The proposed model can be implemented easily. Its convergence rates and accuracy in displacement, energy and pressure are even comparable to those of second-order mixed elements.

This paper aims to investigate the effects of different ultrasonic-assisted loading degrees on the microstructure, mechanical properties and the fracture morphology of Cu/Zn+15%SAC0307+15%Cu/Al solder joints.

A new method in which 45 μm Zn particles were mixed with 15% 500 nm Cu particles and 15% 500 nm SAC0307 particles as solders (SACZ) and five different ultrasonic loading degrees were applied for realizing the soldering between Cu and Al at 240 °C and 8 MPa. Then, SEM was used to observe and analyze the soldering seam, interface microstructure and fracture morphology; the structural composition was determined by EDS; the phase of the soldering seam was characterized by XRD; and a PTR-1102 bonding tester was adopted to test the average shear strength.

The results manifest that Al–Zn solid solution is formed on the Al side of the Cu/SACZ/Al joints, while the interface IMC (Cu₅Zn₈) is formed on the Cu side of the Cu/SACZ/Al joints. When single ultrasonic was used in soldering, the interface IMC (Cu₅Zn₈) gradually thickens with the increase of ultrasonic degree. It is observed that the proportion of Zn or ZnO areas in solders decreases, and the proportion of Cu–Zn compound areas increases with the variation of ultrasonic degree. The maximum shear strength of joint reaches 46.01 MPa when the dual ultrasonic degree is 60°. The fracture position of the joint gradually shifts from the Al side interface to the solders and then to the Cu side interface.

The mechanism of ultrasonic action on micro-nanoparticles is further studied. By using different ultrasonic loading degrees to realize Cu/Al soldering, it is believed that the understandings gained in this study may offer some new insights for the development of low-temperature soldering methodology for heterogeneous materials.

This paper aims to develop the building information modeling (BIM) investment decision model (BIDM) for Hong Kong architecture, engineering, construction and operation (AECO) industry utilization in early BIM investment decision-making. The developed BIDM is designed to assist company leaders in measuring and amending their investment decisions and BIM strategy by considering estimators [features and net positivity (NP)] and results based on BIDM.

This research is conducted using a mixed methodology of qualitative and quantitative analysis. The necessary indicators were collected from literature and interviews with relevant researchers, where 545 semistructured questionnaires were distributed to selected AECO company leaders and collected by the authors. The least absolute contraction and selection operator (LASSO)-based result was conducted to help company leaders. The results of the validation test validated the model based on the LASSO method and the outcomes of the p-value test also supported the significance of BIDM.

More than 80 determinators were processed to conduct 19 main indicators for generating BIDM, and 6 significant main indicators on final BIDM. The data set of this research included 483 samples, which are categorized into 7 groups according to their role in an infrastructure project.

To the best of the authors’ knowledge, this is the first LASSO-used investment decision-making model integrated with the proposal of NP in the AECO industry. The value of current knowledge is the development of BIDM, which benefits company leaders in BIM investment decision-making and commercially benefits consulting cooperators as an investment forecasting tool. BIDM will help future users make better, more dynamic investment strategies.

The purpose of this study is to explore the effects of priming on consumer emotions and willingness to pay as consumers experience two services with two opposite valences.

A 2 (service experience sequence: failure–success, success–failure) × 3(priming: positive, negative, no priming) between-subject experiment was conducted with 230 college students in China.

Results indicate that when priming information is included, people give greater decision weight to the second service. Specifically, in the failure–success scenario, priming information between two services increases positive emotions and decreases negative emotions, raising willingness to pay. In the success–failure scenario, priming information decreases positive emotions and increases negative emotions, thus lowering willingness to pay.

First, if businesses discover the possibility of a service failure, then disclosing negative information is better than whitewashing the truth. Second, services following a campaign of positively framed messages should be carefully rendered. The damage of pre-failure positive priming is most certainly irreparable. Finally, in terms of communication, businesses and service providers should cater to consumers exposed to different levels of information accordingly.

Previous investigations focusing on a single purchase have argued that priming effects should cause consumers of varying tastes to react in a more unified manner to a service. This study extends the research scope to more realistic situations ”sequential service experiences with opposite valences” and asserts that differences in service experiences alter the influence of priming information.

The purpose of this paper is to investigate a five-phase permanent-magnet synchronous machine (PMSM) that features high-power density and high-fault-tolerant capability for electric vehicles (EVs).

The five-phase 20-slot/18-pole PMSM is designed by finite-element method. Two typical rotor structures which include Halbach array and rotor eccentricity are compared to achieve sinusoidal back electromotive force (EMF). The influence of slot dimensions on leakage inductance and short-circuit current is analyzed. The method to reduce eddy current loss of permanent magnets (PMs) is investigated. The machine performances under both healthy and fault conditions are evaluated. Finally, thermal behavior of the machine is studied by Ansys.

With both no-load and load performances considered, rotor eccentricity is proposed to reduce the harmonic contents of EMF. Increasing slot leakage inductance is an effective way to limit the short-circuit current. By segmenting PMs in circumferential direction, the PM eddy current loss is reduced and the machine efficiency is improved. With proper fault-tolerant control strategy, acceptable torque performance can be achieved under fault conditions. The proposed machine can safely operate under Class F insulation.

So far, many researches focus on multiphase PMSMs used in aviation fields, such as fuel pump and electric actuator. Differing from PMSMs used in aviation applications, machines for EVs require characteristics like wide speed ranges and variable operating conditions. Hence, this paper proposes a five-phase 20-slot/18-pole PMSM for EVs. The proposed design methodology is applicable to multiphase PMSMs with different slot/pole combinations.

Drawing on the premise that the media play a vital corporate governance role, this paper aims to investigate the association between media coverage and financial report restatements.

Based on a sample of Chinese listed companies over the period 2011–2015, the authors use ordinary least squares regression as well as a number of additional tests. To mitigate the endogeneity issue, the authors use a two-stage Heckman test and a propensity score matching model.

The authors document a negative and significant association between media coverage and restatements, suggesting that firms with high media coverage engage less in financial restatements. The authors further explore the moderating effects of internal control quality and state ownership on the association between media coverage and restatements. Regression results reveal that the governance role of the media is more pronounced for state-owned enterprises than for private firms. However, no significant difference in the disciplining effect of media coverage is found for firms with high, versus low, internal control quality.

The role of the media in corporate governance and financial reporting quality has been well documented. In emerging economies, such a role has been overlooked. As a result, the purpose of this study is to fill that void. Furthermore, prior research ignores the impacts of state ownership and the internal control environment on the media's governance role.

Although there have been extensive studies on the hydrological and erosional impacts of logging, relatively little is known about the impacts of conversion into agricultural plantation (namely rubber and oil palm). Furthermore, studies on morphological impacts, sediment-bound chemistry and forensic attribution of deposited sediment to their respective sources are scarcer. This chapter introduces the potential for using the multi-proxy sediment fingerprinting technique in this context. Featuring pilot projects in two major flood-prone river systems in Malaysia, the studies explore application of geochemistry-based sediment source ascription. The geochemical signatures of sediment mixtures on floodplains were compared to sediments from upstream source tributaries. The tributaries were hypothesised to have different geochemical signatures in response to dominant land management. The first case study took place in the Segama River system (4,023 km²) of Sabah, Malaysian Borneo where a mixture of primary forest, logged-forests and oil palm plantations were predominant. The second case study was in the Kelantan River Basin (13,100 km²) with two major tributaries (Galas River and Lebir River) where logged-forests and rubber and oil palm plantations are dominant land-uses. Both case studies demonstrated the applicability of this method in ascribing floodplain deposited sediment to their respective upstream sources. Preliminary results showed that trace elements associated with fertilisers (e.g. copper and vanadium) contribute to agricultural catchment signatures. Alkaline and alkaline-earth elements were linked to recently established oil palm plantations due to soil turnover. Mixing model outputs showed that contributions from smaller, more severely disturbed catchment are higher than those from larger but milder disturbed catchments. This method capitalises on flood events to counter its adverse impacts by identifying high-priority sediment source areas for efficient and effective management.

It is predicted that the bitcoin system will enter many areas of our lives in the future. Although it has many benefits, the most criticized issue of this system is excessive energy consumption. Since an excessive amount of energy is used in this process, it is vital that the preferred energy is environmentally friendly. For example, mining bitcoin with fossil fuels is likely to release a significant amount of carbon gas into the atmosphere. This will cause serious environmental problems. Therefore, great attention should be paid to the type of energy that will be used in bitcoin mining. In this study, it was stated that it would be beneficial to prefer nuclear energy in bitcoin mining. As a result of the use of nuclear energy, no carbon gas is released into the atmosphere. This will help reduce environmental pollution to a significant extent. Another dimension of nuclear energy being preferred in bitcoin mining is that the energy produced is continuous. The main reason for this is that nuclear energy is not affected by climatic conditions and temperature differences. Thanks to the preference of nuclear energy in bitcoin mining, it will be possible to contribute to the uninterrupted progress of this process.

Drawing on the self-concept-based theory, this study aims to consider subordinate moqi as a source of forming self-concept to develop a conceptual model to examine the relationships between subordinate moqi and employee creativity, including self-efficacy as a mediator and face consciousness as a moderator.

An online survey was conducted and 188 subordinate-supervisor paired samples were collected in China. This paper applied the multiple linear regression method to test the proposed hypotheses.

Results show that subordinate moqi is positively related to employee creativity, and employee self-efficacy mediates the positive relationship between subordinate moqi and employee creativity. Additionally, face consciousness moderates the positive effect of self-efficacy on employee creativity and the indirect effect of subordinate moqi on employee creativity via employee self-efficacy.

These findings suggest that employees, managers and organizations should foster subordinate moqi, especially for the managers whose subordinates have low-level creativity. Moreover, fostering subordinate moqi can enhancing employee self-efficacy and further promote employee creativity. Additionally, our findings show the moderating role of face consciousness. That is, face consciousness can be regarded as a management tool to inspire employees’ intrinsic motivation to achieve goal tasks. Especially in the Chinese context, the face culture is quite prominent.

The findings provide empirical evidence on how and when subordinate moqi promote employee creativity. This study enriches our understanding of subordinate moqi.

The purpose of this paper is to propose a new three-node triangular element in the framework of the numerical manifold method (NMM), which is designated by Trig3-MLScns.

The formulation uses the improved parametric shape functions of classical triangular elements (Trig3-0) to construct the partition of unity (PU) and the moving least square (MLS) interpolation method to construct the local approximation function.

Compared with the classical three-node element (Trig3-0), the Trig3-MLScns element has a higher order of approximations, much better accuracy and continuous nodal stress. Moreover, the linear dependence problem associated with many PU-based methods with high-order approximations is eliminated in the present element. A number of numerical examples indicate the high accuracy and robustness of the Trig3-MLScns element.

The proposed element inherits the individual merits of the NMM and the MLS.