101 research outputs found
Bibliometric analysis on the implementation digitization technologies in cultural heritage in Malaysia
Malaysia is a rich country with significant tangible and diverse intangible cultural heritage assets. The cultural heritage information must be collected in order to transmit the information to future generations. In this digital era, knowledge transmission can be easily spread using digital platforms. Furthermore, the post-Covid-19 pandemic driven necessity of digital sharing platforms. However, the status of digital cultural heritage in Malaysia is unknown. Hence, this paper will be addressed the digitization of cultural heritage implementation in Malaysia based on the published research articles. The data extracted from the Web of Science and Scopus database has been analysed using bibliometric analysis. The search keywords related to the digitization of cultural heritage has extracted about 171 documents over 15 years of publication. This finding is significant to provide local researchers and related institutions with the potential of digital cultural heritage in a post-Covid-19 pandemic. The large potential of digital cultural heritage should motivate local researchers to increase the attention on digitization cultural heritage research area. Many potential applications which are benefited cultural heritage tourism, sustainability as well as contribution to the economy. The findings from this research indicate that the trend of digitization in the cultural heritage field needs to be strengthened
Investigating the surface tribology of roller-burnished polymer using the fuzzy rule-based approach
Burnishing is specified as the plastic deformation cold working process applied as surface treatment and smoothing following machining to obtain a superior surface roughness finish. The present experimental study was carried out on roller-burnished polyurethane using a roller burnishing tool. An analysis was done to investigate the effect of burnishing depth, speed, feed rate, and roller width on the surface roughness of the polymer workpiece. Roughness (R-a) prediction was achieved with a fuzzy rule-based system. The results indicate 95 accuracy between the fuzzy predicted roughness values and experimental results
Preparation, scratch adhesion and anti-corrosion performance of TiO2-MgO-BHA coating on Ti6Al4V implant by plasma electrolytic oxidation technique
Bovine hydroxyapatite (BHA) (from cortical bone), was selected as the main electrolyte for plasma electrolytic oxidation (PEO) on Ti6Al4V implant. The prepared PEO coatings were examined by X-ray diffraction, field emission scanning electron microscope and energy-dispersive X-ray spectroscopy. The surface roughness, adhesion strength, wettability, surface energy and corrosion behaviour of the film were also investigated. The results show that the oxide layer (26 μm) formation on the Ti6Al4V was rough and porous. The micro-pores were filled with anatase TiO2, cubic MgO and hexagonal BHA particles. The porous structures and the compound particles were mainly composed of Mg, O, Ca, P, Ti, Na and Al. Unlike previous coatings produced from calcium and phosphorus inorganic solutions, the coating formation from a newly developed bovine bone-derived HA electrolyte revealed an additional MgO phase in the coating layer. Moreover, higher amount of single phase hexagonal crystalline BHA phase with a Ca/P ratio of 1.1 was achieved with a single PEO process. A film-to-substrate adhesion strength of 1862.24 mN and scratch hardness of about 4.1 GPa was achieved from this method. The TiO2/MgO/BHA film exhibited better wettability, higher surface energy and superior corrosion resistance compared to the bare Ti6Al4V substrate
A Study on Surface Modification of Al7075-T6 Alloy against Fretting Fatigue Phenomenon
Aircraft engines, fuselage, automobile parts, and energy saving strategies in general have promoted the interest and research in the field of lightweight materials, typically on alloys based on aluminum. Aluminum alloy itself does not have suitable wear resistance; therefore, it is necessary to enhance surface properties for practical applications, particularly when aluminum is in contact with other parts. Fretting fatigue phenomenon occurs when two surfaces are in contact with each other and one or both parts are subjected to cyclic load. Fretting drastically decreases the fatigue life of materials. Therefore, investigating the fretting fatigue life of materials is an important subject. Applying surface modification methods is anticipated to be a supreme solution to gradually decreasing fretting damage. In this paper, the authors would like to review methods employed so far to diminish the effect of fretting on the fatigue life of Al7075-T6 alloy. The methods include deep rolling, shot peening, laser shock peening, and thin film hard coatings. The surface coatings techniques are comprising physical vapor deposition (PVD), hard anodizing, ion-beam-enhanced deposition (IBED), and nitriding
A novel inertia moment estimation algorithm collaborated with active force control scheme for wheeled mobile robot control in constrained environments
This paper presents a novel inertia moment estimation algorithm to enable the Active Force Control Scheme for tracking a wheeled mobile robot (WMR) effectively in a specific trajectory within constrained environments such as on roads or in factories. This algorithm, also known as laser simulator logic, has the capability to estimate the inertia moment of the AFC-controller when the robot is moving in a pre-planned path with the presence of noisy measurements. The estimation is accomplished by calculating the membership function based on the experts’ views in any form (symmetric or non-symmetric) with lowly or highly overlapped linguistic variables. A new Proportional-Derivative Active Force Controller (PD-AFC-LS-QC), employing the use of laser simulator logic and quick compensation loop, has been developed in this paper to robustly reject the noise and disturbances. This controller has three feedback control loops, namely, internal, external and quick compensation loops to compensate effectively the disturbances in the constrained environments. A simulation and experimental studies on WMR path control in two kinds of environments; namely, zigzag and highly curved terrains, were conducted to verify the proposed algorithm and controller which was then compared with other existed control schemes. The results of the simulation and experimental works show the capability of the proposed algorithms and the controller to robustly move the WMR in the constrained environments
Synthesis of Ti(SO4)O solid acid nano-catalyst and its application for biodiesel production from used cooking oil
A novel solid acid nano-catalyst [Ti(SO4)O] was synthesised and used for the simultaneous esterification and transesterification of free fatty acids in used cooking oil (UCO) to produce biodiesel. The synthesised nano-catalyst was fully characterized by different analytical techniques. The XPS results clearly confirmed that the bidentate sulphate coordinated to the Ti4+ metal in the nano-catalyst product. Obtained d-spacing values from the experimental data of XRD peaks and the SAED pattern of produced nano-catalyst agreed well with the d-spacing values from the JCPDS-ICDD card numbers 04-011-4951 for titanium sulphate oxide or titanium oxysulfate crystal structures.This confirms the sulphate groups were within the crystalline structure rather than on the surface of titania nanoparticles, which has not been previously reported. It has been demonstrated 97.1% yield for the fatty acid methyl ester can be achieved usign the synthetised catalyst under a reaction time of 3 h, catalyst to UCO ration of 1.5 wt% and methanol to UCO ratio of 9:1 at 75 °C reaction temperature. The nano-catalyst showed a good catalytic activity for the feedstock containing ≤6 wt% free fatty acid. Furthermore, the catalytic activity and re-usability of the Ti(SO4)O for the esterification/transesterification of UCO were investigated. XRD results confirmed that the amount of View the MathML source species in the solid acid nano-catalyst slowly decreased with re-use after 8 cycles under optimised conditions, which is higher than the reusability of other functionalised titania reported in the literature. Finally, the biodiesel prodcued from this process satisfied the ASTM and European Norm standards
Properties of Ta2O5 thin films prepared by ion-assisted deposition
Tantalum penta-oxide (Ta2O5) thin films were deposited onto highly polished and clean, fused silica glass substrates via ion beam-assisted deposition at room temperature using a high-vacuum coater equipped with an electron beam gun. The effects of ion beam parameters, oxygen flow rate, and deposition rate on the optical and structural properties as well as the stress of Ta2O5 films were studied. It has been revealed that Ta2O5 thin films deposited at 300 eV ion beam energy, 60 μA/cm2 ion current density, 20 sccm oxygen flow rate and 0.6 nm/s deposition rate demonstrated excellent optical, structural and compressive stress
Plasma Non-Transferred Arc Cladding of Alumina Powder on Mild Steel-Parameters Optimization Using Taguchi Method
This research described the optimization of the process parameters for clad coating of alumina (Al2O3) powder on AISI 1018 mild steel utilizing plasma non-transferred arc cladding process using Taguchi method and Pareto ANOVA analysis. Four factors were selected which were plasma arc current, plasma torch velocity, distance between nozzle and layer and ratio of alumina powder to binder. The analysis of the results showed that the optimal combination for high microhardness were distance between nozzle and layer at 3 mm and plasma torch velocity at 0.03 mm
Comparative investigation on the adhesion of hydroxyapatite coating on Ti–6Al–4V implant: A review paper
Hydroxyapatite (HA) has been used in clinical bone graft procedures for the past 25 years. Although a biocompatible material, its poor adhesion strength to substrate makes it unsuitable for major load-bearing devices. Investigations on various deposition techniques of HA coating on Ti–6Al–4V implants have been made over the years, in particular to improve its adhesion strength to the metal alloy and its long-term reliability. This review comprehensively analyzes nine techniques mostly used for deposition of HA onto Ti–6Al–4V alloys. The techniques reviewed are Plasma sprayed deposition, Hot Isostatic Pressing, Thermal Spray, Dip coating, Pulsed Laser deposition (PLD), Electrophoretic deposition (EPD), Sol–Gel, Ion Beam Assisted deposition (IBAD), and Sputtering. The advantages and disadvantages of each method over other techniques are discussed. The adhesion strength and the factors affecting the adhesion of HA coating on Ti–6Al–4V implants are also compared
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