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Material extrusion technology is considered to be an effective way to realize the accurate and integrated manufacturing of high-performance metal diamond tools with complex structures. The present work aims to report the G4 binder that can be used to create metal composite filament loading high concentrations of large diamond particles through comparative experiments.

The quality of filaments was evaluated by surface topography observation and porosity measurement. And the printability of filaments was further studied by the tensile test, rheological test, shear analysis and printing test.

The results show that the G4 binder exhibits the best capacity for loading diamonds among G1–G4. The L4 filament created with G4 has no defects such as pores, cracks and patterns on the surface and section, and has the lowest porosity, which is about 1/3 of the L1. Therefore, the diamond-containing composite filament based on G4 binder exhibits the best quality. On the other hand, the results of the tensile test of L5–L8 filaments reveal that as the diamond content increases from 10% to 30%, the tensile strength of the filament decreases by 29.52%, and the retention force coefficient decreases by 15.74%. This can be attributed to the formation of inefficient bonding areas of the clustered diamond particles inside the composite filament, which also leads to a weakening of the shear strength. Despite this, the results of the printing test show that the diamond-containing composite filament based on the G4 binder has reliable printability.

Therefore, the G4 binder is considered to solve the most critical first challenge in the development of diamond-containing filament.

The purpose of this paper is to study a new method with which multi‐walled carbon nanotubes (MWNTs) can be dispersed and aligned in low density polyethylene (LDPE) for improving its mechanical properties.

Dispersion and alignment of MWNTs in LDPE matrix are enhanced by ultrasonic vibration, solution casting and melt mixing and flow moulding method. The properties of the composite are characterised using scanning electron microscopy, tensile testing machine and the Izod impact testing machine.

It is found that MWNTs in LDPE achieve some dispersion and alignment resulting in improvement in LDPE's strength and toughness.

Polymer/CNTs nanocomposites are expected to have good process ability of the polymers and high mechanical and functional properties of the CNTs. Enhancing dispersion and alignment of MWNTs in the polymer matrix will promote and expand the applications and development of polymer/MWNTs nanocomposites.

The method that enhances MWNTs dispersion and alignment in LDPE matrix provides a new way for alignment of other CNTs in polymer matrix.

This study aims to find a novel solution to the calibration of three-axis magnetometers to suppress errors of sensors. The nature of the calibration process is parameter estimation and hence the purpose of the paper is to calculate the error parameters and eliminate sensor errors and obtain the true value of the pure magnetic field.

The paper puts forward a calibration method using an alternative iteration looping optimization (AILO) to estimate the parameters. The proposed method divided the parameters to be estimated into two parts: a portion less than one and the other greater than one. Parameters with different orders of magnitude are calculated respectively, which let one part to be a known quantity and the other part is derived by the known quantity; the derived quantity is used to calculate the known quantity again, and looping iteration multiple times until the iteration termination condition is satisfied.

The simulation and experimental results indicate that the calibration accuracy is improved at least by two orders by the proposed method compared to the two-step method and the linear decreasing weight particle swarm optimization (LDW-PSO) algorithm which proves the validity of the proposed method.

The proposed method can improve the calibration accuracy of total magnetic field, which provides a reference to the calibration of three-axis magnetometers.

A calibration method based on the AILO is proposed in this paper, which is used to improve the calibration accuracy of the three-axis magnetometer.

This paper aims to reveal the mechanism for improving ductile machinability of 3C-silicon carbide (SiC) and associated cutting mechanism in stress-assisted nanometric cutting.

Molecular dynamics simulation of nano-cutting 3C-SiC is carried out in this paper. The following two scenarios are considered: normal nanometric cutting of 3C-SiC; and stress-assisted nanometric cutting of 3C-SiC for comparison. Chip formation, phase transformation, dislocation activities and shear strain during nanometric cutting are analyzed.

Negative rake angle can produce necessary hydrostatic stress to achieve ductile removal by the extrusion in ductile regime machining. In ductile-brittle transition, deformation mechanism of 3C-SiC is combination of plastic deformation dominated by dislocation activities and localization of shear deformation. When cutting depth is greater than 10 nm, material removal is mainly achieved by shear. Stress-assisted machining can lead to better quality of machined surface. However, there is a threshold for the applied stress to fully gain advantages offered by stress-assisted machining. Stress-assisted machining further enhances plastic deformation ability through the active dislocations’ movements.

This work describes a stress-assisted machining method for improving the surface quality, which could improve 3C-SiC ductile machining ability.

The purpose of this paper is to prepare a new modified activated carbon fibers (ACFs) of high specific capacitance used for electrode material of supercapacitor.

In this study, the specific capacitance of ACF was significantly increased by using the phenolic resin microspheres and melamine as modifiers to prepare modified PAN-based activated carbon fibers (MACFs) via electrospinning, pre-oxidation and carbonization. The symmetrical supercapacitor (using MACF as electrode) and hybrid supercapacitor (using MACF and activated carbon as electrodes) were tested in term of electrochemical properties by cyclic voltammetry, AC impedance and cycle stability test.

It was found that the specific capacitance value of the modified fibers were increased to 167 Fg^-1 by adding modifiers (i.e. 20 wt.% microspheres and 15 wt.% melamine) compared to that of unmodified fibers (86.17 Fg^-1). Specific capacitance of modified electrode material had little degradation over 10,000 cycles. This result can be attributed to that the modifiers embedded into the fibers changed the original morphology and enhanced the specific surface area of the fibers.

The modified ACFs in our study had high specific surface area and significantly high specific capacitance, which can be applied as efficient and environmental absorbent, and advanced electrode material of supercapacitor.

In recent years, a new type of double-layered containment structure of nuclear power plant has been built in China, named ACP1000 NNP. This paper aims to propose a new method to mitigate the seismic responses of this type of the structure.

The new base isolation structure (BIS)- tuned mass damper (TMD) structure was proposed and implemented only by modifying the connection between various components of NPPs, and the application of this concept design in ACP1000 was skillfully realized.

The new structure adopts the combination of structural form and function, adopts appropriate amplification of the seismic response of the secondary component, possesses advantages in explicit damping mechanism, good damping effect, robustness of seismic structures, simple implementation process, etc., and meets the special seismic safety requirements of the NPPs.

This seismic and hazard mitigation and BIS-TMD structure can avoid the risk of ACP1000 accidents caused by horizontal earthquakes.

The purpose of this paper is to explore the relationship between different mechanisms for integrating national archival resources, leading to the development of a knowledge management-based framework for facilitating the optimal utilization of national archives resources in China.

The study adopts a mixed-methods approach consisting of a review of existing mechanisms for integrating national archival resources and site visits and interviews for investigating the effectiveness of these mechanisms in real world practices for managing and utilizing national archives resources in China.

The knowledge management-based framework is shown to be useful for building interdependence, interconnections and interactions between diversified integration mechanisms to meet national, societal and public needs in China. The framework is significant for rearranging the role of knowledge management in collaboration to protect the value of national archives resources as the knowledge asset of a state. It can reengineer the knowledge management activities in communication to share the value of national archives resources as the knowledge asset of a society. Furthermore, the framework can reconfigure knowledge management artifacts in connectivity to increase the value of national archives resources as the knowledge asset of the public.

The review of the related literature is selective rather than comprehensive, and the interviews are based on a self-selected convenience sample, which is rather skewed demographically.

The proposed framework can be used to guide the development of a national strategy for the effective integration of national archives resources to promote a better delivery of public-centric knowledge services in a specific society.

This study provides a knowledge management framework for the effective integration of national archives resources toward their optimal utilization. It contributes to the examination of the role of different integration mechanisms in interactive knowledge management processes and the advancement of academic debate on the effectiveness of these mechanisms for the integration of national archives resources to facilitate their optimal utilization in China.

The purpose of this paper is to explore the influence of personal values on students’ learning behaviours. Hong Kong construction students are often criticized, by both practitioners and educators, as rote learners. To improve students’ learning processes, extensive research on a variety of aspects of construction education has been conducted. However, limited attention has been paid to the influence of personal values on students’ learning behaviours. The impact of personal value factors on the learning approaches of Chinese construction students in Hong Kong is investigated.

A questionnaire survey was conducted to ethically Chinese construction students in four universities in Hong Kong. A total of 820 questionnaires were distributed and 431 valid returns were collected.

The survey identified six influential values (namely, personal integrity, conservatism, determination, discipline, interpersonal relationships, and achievement), and shows that students who emphasize the virtues of personal integrity, determination, and a positive attitude toward achievement are better able to handle their interpersonal relationships, which will eventually lead them to engage in deep learning.

Work to develop appropriate value systems is thus recommended in freshmen courses, as is the use of cooperative learning approaches. Such value systems will have a long-term influence on the learning approaches of construction students.

The negative effects of job stress and burnout on construction professionals (CPs) at the construction site have been widely concern in the construction industry. The purpose of this study is committed to explore the impact of job stress on CPs on the construction site, especially in the context of the widespread use of social media to express their emotions.

This study developed a job-related stress-burnout-health conditions-turnover intention (S-B-HT) framework to explore the direct and lagged effects of job stress, we also examined the moderating effects of online emotions, operationalized in terms of emotional intensity and expression pattern, on the relationship between job stress with job burnout under two evolution paths (i.e. health conditions or turnover intention). This study collected 271 samples through a survey questionnaire for empirical testing, and introduced structural equation models to validate the proposed conceptual model.

The results show that job stress has a significant positive effect on job burnout, and job burnout maintains a positive relationship with health conditions (or turnover intention) under the interference mechanism. Simultaneously, the online emotions expressed in social media have a positive moderating effect in two stages of the evolution path.

The findings of this study remind the project manager need to timely find and solve the job burnout characteristics of CPs due to excessive job stress, especially to prevent the accidental consequences caused by job burnout.

On this basis, this study provides an important value of using social media to express emotions for the project team to alleviate the adverse of professionals under job stress.

The past few decades have produced a number of investigations into the correlation between project managers’ competencies and project success. As a result, competencies lists have become extensive “shopping lists.” The purpose of this paper is to define the most important competencies to project success and investigate their correlations.

The authors surveyed project managers on the importance of 28 project manager competencies to project success. Data were analyzed using univariate and multivariate procedures.

Data show that communication, commitment and leadership appear as the three most relevant aspects. Multivariate analysis identified seven groups of competencies: leadership, self-management, interpersonal, communication, technical, productivity and managerial.

The results confirm a growing trend toward soft skills and reinforce the need for an update on project management education to fill the gap between theory and practice.

Project manager competencies lists have become too extensive, and the field is in constant change; therefore, this study updates the discussion and downsizes the number of competencies to fewer, more relevant items.