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This paper aims to conduct work to obtain high-quality brazed joint of YAG ceramic and kovar alloy.

Wetting and spreading behavior of AgCuTi filler alloy on YAG ceramic and kovar alloy under vacuum (2∼3 × 10–4 Pa) and argon conditions was investigated and compared. Then, YAG ceramic was brazed to kovar alloy under a high vacuum of 2∼3 × 10–4 Pa; the influence of holding time on the interface structure of the joint was investigated.

The wettability of AgCuTi on YAG is poor in the argon atmosphere, the high oxygen content in the reaction layer hinders the formation of the TiY2O5 reaction layer, thereby impeding the wetting of AgCuTi on YAG; in the vacuum, a contact angle (?=16.6°) is obtained by wetting AgCuTi filler alloy on the YAG substrate; the microstructure of the YAG/AgCuTi/kovar brazed joint is characterized to be YAG/Y2O3/(Fe, Ni)Ti/Ag(s, s) + Cu(s, s)/Fe2Ti + Ni3Ti/Fe2Ti/kovar; at 870 °C for the holding time of 10 min, a (Fe, Ni) Ti layer of approximately 1.8 µm is formed on the YAG side.

Wetting and spreading behavior of the brazing filler alloy under different conditions and the influence of the holding time on the interface microstructure of the joint were studied to provide references for obtaining high-quality brazed joints.

The objective of this study is to assess whether pro-health herbal probiotics, ascorbic acid and allicin added to the finishing diets of hybrid pig influenced the intramuscular fat (IMF) content in longissimus lumborum (LL) muscle, the fatty acid profile and lipid quality indices, as it has an impact on human health.

After 80 days of equal fattening, the pigs were divided into the control group (CT, n = 30 received commercially allowed and applicable antibiotics) and the experimental group (EX, n = 30), which until 95 days of rearing were supplied with fermented herbs extract (FHE Multikraft® Austria) with probiotics Saccharomyces cerevisiae, Lactobacillus casei, Lactobacillus plantarum, L-ascorbic acid and extract of garlic (10% allicin). After slaughter, crude fat content and fatty acid profile were determined in LL muscle samples, and on that basis lipid indices were calculated.

Supplementation with FHE, probiotics, L-ascorbic acid and allicin has significantly impacted the crude fat content in the meat and the percentage of fatty acids content: tricosanoic (C23:0), heptadecanoid (C17:1 n-7), eicosanic (C22:1 11cis n-9) and eicosatrienoic (C20:3 11cis n-3), in comparison to CT group. Amongst lipid quality indices, IMF in LL of pigs from EX group, the C18:2 n-6/C18:3 n-3 ratio is characterised by a significantly higher value and thus is more beneficial to the health of the consumer.

The authors have indicated that using FHE, probiotic supplements with ascorbic acid and allicin in commercial fattening of pigs, as an alternative for antibiotic growth promoters (AGP), improves the fatty acid profile of the meat.

The rope-climbing robot that can cling to a rope for locomotion has been a popular piece of equipment for some overhead applications due to its high flexibility. In view of problems left by existing rope-climbing robots, this paper aims to propose a new-style rope-climbing robot named Finger-wheeled mechanism robot (FWMR)-II to improve their performance.

FWMR-II adopts a modular and link-type mechanical structure. With the finger-wheeled mechanism (FWM) module, the robot can achieve smooth and quick locomotion and good capability of obstacle-crossing on the rope and with the link module based on a spatial parallel mechanism, the robot adaptability for rope environments is improved further. The kinematic models that can present configurations of the FWM module and link module of the robot are established and for typical states of the obstacle-crossing process, the geometric definitions and constraints that can present the robot position relative to the rope are established. The simulation is performed with the optimization calculating method to obtain the robot adaptability for rope environments and the experiment is also conducted with the developed prototype to verify the robot performance.

From the simulation results, the adaptability for rope environments of FWMR-II are obtained and the advantage of FWMR-II compared with FWMR-I is also proved. The experiment results give a further verification for the robot design and analysis work.

The robot proposed in this study can be used for inspection of power transmission lines, inspection and delivery in mine and some other overhead applications.

An ingenious modular link-type robot is proposed to improve existing rope-climbing robots and the method established in this study is worthy of reference for obstacle-crossing analysis of other rope-climbing robots.

This paper aims to examine the technology acceptance model’s applicability in understanding employees’ acceptance of online platforms for knowledge sharing in organisations. Specifically, this research explores gender differences in using online platforms for sharing knowledge at the workplace in an emerging market context and the role of individuals’ motivation in online platform usage in organisations.

A web-based survey was conducted in Vietnam with 290 responses from employees in the banking and insurance industries.

Both intrinsic and extrinsic motivations influenced the perceived ease of use, perceived usefulness and online platform usage for knowledge sharing. The results also confirm a significant influence of perceived ease of use directly on knowledge sharing behaviour using online platforms and indirectly via perceived usefulness. Regarding gender differences, perceived ease of use was more salient in women, while men considered perceived usefulness to a greater extent.

This study provides a complete picture of gender, motivation and technology used for knowledge sharing in organisational settings.

This research has provided additional insight into the importance of gender and motivation in technology acceptance. By doing this, this study helps organisations capture the potential of valuable human resources for their competitiveness.

This paper aims to answer the following two questions: What are the affecting factors of platform leadership? How do the business ecosystem and unique attributes of platform enterprises affect the formation of platform leadership?

Based on the niche theory, this study used the grounded theory research methods to explore the strategic behavior of platform enterprises, analyze the characteristics of platform leadership and systematically explore the influencing factors of platform leadership based on four internet platform enterprises and their business ecosystem.

The result shows that the acquisition of platform leadership is closely related to the platform enterprises’ Niche, where they are located in the business ecosystem. Platform enterprises play the roles of the founder, coordinator, leader and arranger in the ecosystem, and there are four affecting factors of platform leadership: architecture foundation, connection and coordination, innovation leading and integrated expansion. The architecture foundation consists of four factors: platform architecture, installation base, intellectual property and network coverage; the connection and coordination contain five factors: interactive collaboration, multilateral user connection, information matching, neutral arbitration and mutualism; the innovation leading is composed of four factors: research and development investment, common components, complementary innovation, cross-border search and standard-setting; the integrated expansion includes resource orchestration, modular design, data collaboration, supportive enabling and scenario application.

This research constructs a framework of platform leadership with the influencing factors.

This article’s indented contribution is to provide novel theoretical insights and empirical observations on “who gets what” in the way of incomes, including wages. The article challenges the conventional wisdom about stratification, especially power and status, as an outcome or function of economic distribution. It posits that income distribution is conditional on pre‐existing social stratification expressed in antecedent differences in class, power, status and related factors.

This paper aims to investigate the impact of anodizing time and heat treatment on morphology, phase and corrosion resistance of formed coating. To characterize the anodic oxide layer, X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM) that was equipped with energy dispersive spectroscopy (EDS) was hired. The corrosion behavior of oxide-coated samples was estimated by electrochemical polarization test in simulated body fluid (SBF).

Anodic oxidation method is applied to reinforce the corrosion and biological properties of biomaterials in the biomedical industry. In this paper, the alkaline NaOH (1 M) electrolyte was used for AZ31 magnesium alloy anodizing accompanied by heat treatment in the air.

It can be concluded that the best corrosion resistance belongs to the 10 min anodic oxidized sample and among the heat-treated samples the 30 min anodized sample represented the lowest corrosion rate.

In this study, to the best of the authors’ knowledge for the first time, this paper describes the effect of anodizing process time on NaOH (1 M) electrolyte at 3 V on corrosion behavior of magnesium AZ31 alloy with an alternate method to change the phase composition of the formed oxide layer. The morphology and composition of the obtained anodic oxide layer were investigated under the results of SEM, EDS and XRD. The corrosion behavior of the oxide coatings layer fabricated on the magnesium-based substrate was studied by the potentiodynamic polarization test in the SBF solution.

The purpose of this paper is to study the influence of braking speed at –20 °C on the wear property of high-speed railway braking materials and the temperature also stress analyses of brake disc friction surface.

Friction brake tester was used to simulate the wear test of high-speed railway braking materials at diverse braking speeds (2,100, 2,400, 2,700 and 3,000 rad/min) at –20 °C and the stress and temperature analyses of brake disc friction surface were carried out by COMSOL.

Compared with 20°C, there is initial stress of brake disc friction surface before brake starting; also, the maximum wear depth is larger at –20°C. Besides, at –20 °C, with the rising of braking speed, the graphite particles on the friction surface of brake pad significantly reduce. And scratches and cracks are formed on brake pad friction surface. Besides, the abrasive wear, adhesive wear and thermal cracks of brake disc friction surface are aggravated. Moreover, the maximal worn depth also increase. Meanwhile, the highest temperature and the maximum thermal stress of brake disc friction surface both raise. Furthermore, the temperature and thermal stress gradients at radial direction of brake disc friction surface aggrandize, which makes the thermal cracks on brake disc friction surface further exacerbated.

In this paper, the wear property of the high-speed railway braking materials is studied by combining experiment and simulation. However, due to the low-speed traveling of high-speed railway was mainly studied in this paper, there may be no comprehensive simulation of the real running condition of high-speed railway. At the same time, the working condition of low-temperature environment cannot be completely simulated and controlled.

The research results of this paper provide a basic instruction for other researchers and also provide an important reference for relevant personnel to choose the braking speed of high-speed railway at –20 °C.

The research of this paper provides a brick for the study of high-speed railway braking materials and also provides some references for the safe service of trains in low-temperature environment.

This paper studied the wear property and carried out the simulation analysis of braking materials at –20 °C at diverse braking speed. The research findings provide an important reference for the selection of braking speed of high-speed railway at –20 °C.

To use distinct element simulation (PFC2D) to investigate the relationships between microparameters and macroproperties of the specimens that are modeled by bonded particles. To determine quantitative relationships between particle level parameters and mechanical properties of the specimens.

A combined theoretical and numerical approach is used to achieve the objectives. First, theoretical formulations are proposed for the relationships between microparameters and macroproperties. Then numerical simulations are conducted to quantify the relationships.

The Young's modulus is mainly determined by particle contact modulus and affected by particle stiffness ratio and slightly affected by particle size. The Poisson's ratio is mainly determined by particle stiffness ratio and slightly affected by particle size. The compressive strength can be scaled by either the bond shear strength or the bond normal strength depending on the ratio of the two quantities.

The quantitative relationships between microparameters and macroproperties for parallel‐bonded PFC2D specimens are empirical in nature. Some modifications may be needed to model a specific material. The effects of the particle distribution and bond strength distribution of a PFC2D specimen are very important aspects that deserve further investigation.

The results will provide guidance for people who use distinct element method, especially the PFC2D, to model brittle materials such as rocks and ceramics.

This paper offers some new quantitative relationships between microparameters and macroproperties of a synthetic specimen created using bonded particle model.

Chemical mechanical polishing (CMP) has attracted much attention recently because of its importance as a nano-scale finishing process for high value-added large components that are used in the aerospace industry. The paper aims to discuss these issues.

The characteristics of aluminum nanoparticles slurry including oxidizer, oxidizer contents, abrasive contents, slurry flow rate, and polishing time on aluminum nanoparticles CMP performance, including material removal amount and surface morphology were studied.

Experimental results indicate that the CMP performance depends strongly on the oxidizer, oxidizer contents, and abrasive contents. Surface polished by slurries that contain nano-Al abrasives had a lower surface average roughness (Ra), lower topographical variations and less scratching. The material removal amount and the Ra were 124 and 7.61 nm with appropriate values of the process parameters of the oxidizer, oxidizer content, abrasive content, slurry flow rate and polishing time which were H₂O₂, 2 wt.%, 1 wt.%, 10 ml/min, 5 min, respectively.

Based on SEM determinations of the process parameters for the polishing of the surfaces, the CMP mechanism was deduced preliminarily.