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Aluminium is the most preferred material in engineering structural components because of its excellent properties. Furthermore, the properties of aluminium may be enhanced through metal matrix composites and an in-depth investigation on the evolved properties is needed in view of metallurgical, mechanical and tribological aspects. The purpose of this study is to explore the effect of TiC addition on the tribological behavior of aluminium composites.

Aluminium metal matrix composites at different weight percentage of titanium carbide were produced through powder metallurgy. Produced composites were subjected to sliding wear test under dry condition through Taguchi’s L9 orthogonal design.

Optimal process condition to achieve the minimum wear rate was identified though the main effect plot. Sliding velocity was identified as the most dominating factor in the wear resistance.

The production of components with improved properties is promoted efficiently and economically by synthesizing the composite via powder metallurgy.

Though the investigations on the wear behavior of aluminium composites are analyzed, reinforcement types and the mode of fabrication have their significance in the metallurgical and mechanical properties. Thus, the produced component needs an in-detail study on the property evolution.

Academic adjustment is an important indicator which represents the students' academic achievements. The purpose of this investigation is to examine the fundamental role of academic adjustment for the success of student's by considering the influence of several psychological, motivational and behavioral factors that affect the academic adjustment of students in the university which then influences the students' academic achievements.

Data were gathered through self-administered questionnaires from 409 students enrolled in a Business degree program in an academic institution by using a convenience sampling technique. Structural equation modeling (SEM) technique has been applied for analyzing the data and the proposed hypothesis.

Results obtained from partial least square (PLS)-SEM analysis indicated that academic adjustment is affected by psychological, motivational and behavioral factors and in turn influences the outcomes of success. Moreover, the findings also showed that psychological and motivational factors, directly and indirectly via partial mediation of adjustment, and behavioral factors via full mediation of academic adjustment influences the outcomes of success.

The study implies that it is important for university policymakers that they should give great priority to fully exploiting its potential to facilitate student's effective adjustment to academic life. Universities should pay attention to enhancing the academic study skills of students which leads to gains in academic achievement. Furthermore, universities should integrate self-regulated skills and provides motivation to students which is the biggest contributor toward adjustment as well as this study broadens the understanding of psychological capital as a resource that enhances academic adjustment.

Very little attention has been given to examining the role of academic adjustment in the success of students. Therefore, the present study makes two contributions to this research. First, the study broadens the understanding of psychological capital with the potential to strengthen adjustment with academic life in domains, i.e. academic achievement and institutional adjustment. Second, the study identifies which motivational and behavioral factors affect academic adjustment and achievement.

The purpose of this paper is to evaluate the perceptions of research priorities as expressed by people with spinal cord injury (SCI).

A descriptive study based on feedback from patients, rehabilitated following SCI was conducted in order to explore their felt needs for further research. A questionnaire was sent to 225 people who were rehabilitated following SCI. They were asked to indicate three priorities for further research on disability related issues. The questionnaire had a list of issues on different facets of disability following SCI. In total, 62 patients responded to the questionnaire.

Research on urinary incontinence was stated to have the highest priority among these different groups according to their age, marital status, duration of disability, and employment status. Rehabilitated patients of all age groups, irrespective of marital or employment status or duration of disability, indicated that further research is to be done on urinary incontinence.

A similar study among groups in a larger population would add further information.

Practitioners should address these expressed needs of the persons with SCI in the community.

These expressed needs will increase awareness among the team involved in the management of SCI in the community thus fill the gap between research and practice.

Research focussing on various problems associated with spinal cord injury have been carried out globally. On most of the occasions, the perceptions of the affected people regarding research areas are seldom obtained. This research would guide future directions of rehabilitation research in the field of spinal cord injury.

Compression ignition engines are being used in transportation, agricultural and industrial sectors due to its durability, fuel economy and higher efficiency. This paper aims to present investigation focuses on the utilization of nano additives in emulsified blends of Pongamia biodiesel and its impact on combustion, emission and performance characteristics of a diesel engine.

Pongamia biodiesel was produced through two-stage transesterification process. Taguchi method with L₉ Design of experiment was adopted to study the stability of fuel blends and 75 per cent diesel, 20 per cent biodiesel, 5 per cent water and 6 per cent of surfactant was found to be stable. Further, aluminum oxide nanoparticle was blended into the emulsified fuel in mass fraction of 100 ppm (D75-BD20-W5-S6-AO100) through ultrasonicating technique.

Oleic acid was found to be in prominent proportion in the Pongamia biodiesel. It was observed that D75-BD20-W5-S6 and D75-BD20-W5-S6-AO100 had the ability to produce lower in-cylinder pressure and rate of heat release compared to D100, B100 and D75-BD20 fuel blends. However, a higher rate of pressure rise was noticed in D75-BD20-W5-S6 and D75-BD20-W5-S6-AO100. Lower brake specific fuel consumption and relatively higher brake thermal efficiency were noticed in D75-BD20-W5-S6 and D75-BD20-W5-S6-AO100. Moreover, lower NO_x and smoke emission were also observed for nano-emulsified fuel blends.

Metal-based nano-additive significantly improved the physio-chemical properties of the fuel. Based on the literature, it is understood that emulsified biodiesel blend with nano enrichment using Pongamia biodiesel as base fuel was not carried out. Identifying a stable blend of diesel-biodiesel-water-nano additive using Taguchi’s design of experiments approach was an added value in formulating the test fuels. Furthermore, the formulated test fuel was compared with mineral diesel, biodiesel, and diesel-biodiesel blend to understand its suitability to use as a fuel in compression ignition (CI) engine.

This study compares the performance of two types of clustering methods, time-based and non-time-based clustering, in the identification of river discharge patterns at the Johor River basin during the northeast monsoon season. Time-based clustering is represented by employing dynamic time warping (DTW) dissimilarity measure, whereas non-time-based clustering is represented by employing Euclidean dissimilarity measure in analysing the Johor River discharge data. In addition, we combine each of these clustering methods with a frequency domain representation of the discharge data using Discrete Fourier Transform (DFT) to see if such transformation affects the clustering results. The clustering quality from the hierarchical data structures of the identified river discharge patterns for each of the methods is measured by the Cophenetic Correlation Coefficient (CPCC). The results from the time-based clustering using DTW based on DFT transformation show a higher CPCC value as compared to that of non-time-based clustering methods.

Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype applications, especially in the development of new products. The purpose of this study is to analyze the current application trends of RT techniques in producing hybrid mold inserts.

The direct and indirect RT techniques discussed in this paper are aimed at developing a hybrid mold insert using metal epoxy composite (MEC) in increasing the speed of tooling development and performance. An extensive review of the suitable development approach of hybrid mold inserts, material preparation and filler effect on physical and mechanical properties has been conducted.

Latest research studies indicate that it is possible to develop a hybrid material through the combination of different shapes/sizes of filler particles and it is expected to improve the compressive strength, thermal conductivity and consequently increasing the hybrid mold performance (cooling time and a number of molding cycles).

The number of research studies on RT for hybrid mold inserts is still lacking as compared to research studies on conventional manufacturing technology. One of the significant limitations is on the ways to improve physical and mechanical properties due to the limited type, size and shape of materials that are currently available.

This review presents the related information and highlights the current gaps related to this field of study. In addition, it appraises the new formulation of MEC materials for the hybrid mold inserts in injection molding application and RT for non-metal products.

The purpose of this study is to analyse and optimize the wear parameters of magnesium metal-metal composite. Materials with lesser weight attract both the researcher and industrialists, as it exhibits the performance improvement in the automotive and aerospace industries. The enrichment of mechanical and tribological properties of the existing magnesium focussed the development of new metal–metal composite.

Metal–metal composite with magnesium matrix was synthesized through the disintegrated melt deposition technique with the addition of titanium, aluminium and boron carbide particles. The wear performance of the composite was experimented with the dry sliding wear test by considering load, sliding velocity and sliding distance.

The wear rate of the composite is analysed statistically, and the significance of wear parameters on the wear performance of metal–metal composite is observed. The worn pin surface and the wear debris collected during the wear experiments were exposed to the microscopy analysis to seize the dominating wear mechanisms.

The wear performance of the developed magnesium composite was analysed and discussed in detail with the support of scientific evidence, i.e. worn surface and debris analysis express the wear mechanisms.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0326/

Aluminium and its alloys are the most preferred material in aerospace and automotive industries because of their high strength-to-weight ratio. However, these alloys are found to be low wear resistance. Hence, the incorporation of ceramic particles with the aluminium alloy may be enhanced the mechanical and tribological properties. The purpose of this study is to optimize the specific wear rate and friction coefficient of titanium dioxide (TiO₂) reinforced AA7075 matrix composites. The four wear control factors are considered, i.e. reinforcement (Wt.%), applied load (N), sliding velocity (m/s) and sliding distance (m).

The composites were fabricated through stir casting route with varying weight percentages (0, 5, 10 and 15 Wt.%) of TiO₂ particulates. The mechanical properties of the composites were studied. The specific wear rate and friction coefficient of the newly prepared composites was determined by using a pin-on-disc apparatus under dry sliding conditions. Experiments were planned as per Taguchi’s L16 orthogonal design. Signal-to-noise ratio analysis was used to find the optimal combination of parameters.

The mechanical properties such as yield strength, tensile strength and hardness of the composites significantly improved with the addition of TiO₂ particles. The analysis of variance result shows that the applied load and reinforcement Wt.% are the most influencing parameters on specific wear rate and friction coefficient during dry sliding conditions. The scanning electron microscope morphology of the worn surface shows that TiO₂ particles protect the matrix from more removal of material at all conditions.

This paper provides a solution for optimal parameters on specific wear rate and friction coefficient of aluminium matrix composites (AMCs) using Taguchi methodology. The obtained results are useful in improving the wear resistance of the AA7075-TiO₂ composites.

Manufacturing errors, which will propagate along the assembly process, are inevitable and difficult to analyze for complex products, such as aircraft. To realize the goal of precise assembly for an aircraft, with revealing the nonlinear transfer mechanism of assembly error, a set of analytical methods with response to the assembly error propagation process are developed. The purpose of this study is to solve the error problems by modeling and constructing the coordination dimension chain to control the consistency of accumulated assembly errors for different assemblies.

First, with the modeling of basic error sources, mutual interaction relationship of matting error and deformation error is analyzed, and influence matrix is formed. Second, by defining coordination datum transformation process, practical establishing error of assembly coordinate system is studied, and the position of assembly features is modified with actual relocation error considering datum changing. Third, considering the progressive assembly process, error propagation for a single assembly station and multi assembly stations is precisely modeled to gain coordination error chain for different assemblies, and the final coordination error is optimized by controlling the direction and value of accumulated error range.

Based on the proposed methodology, coordination error chain, which has a direct influence on the property of stealthy and reliability for modern aircrafts, is successfully constructed for the assembly work of the jointing between leading edge flap component and wing component at different assembly stations.

Precise assembly work at different assembly stations is completed to verify methodology’s feasibility. With analyzing the main comprised error items and some optimized solutions, benefit results for the practical engineering application showing that the maximum value of the practical flush of the profiles between the two components is only 0.681 mm, the minimum value is only 0.021 mm, and the average flush of the entire wing component is 0.358 mm, which are in accordance with theoretical calculation results and can successfully fit the assembly requirement. The potential user can be the engineers for manufacturing the complex products.

The purpose of this study is evaluate the optical properties of polyacrylonitrile (PAN) nanofibers containing fluorescent agents such as fluorescent dye and carbon quantum dots (CQDs) by using image-processing technique of Fluorescence microscope image.

The fluorescence microscope image of the pure PAN, PAN/CQDs and PAN/fluorescent dye nanofibers composite was analyzed using several image-processing techniques such as color histogram, lookup table (LUT), Fourier transform, RGB profile and surface plot analysis.

The fluorescence microscope image indicates that the fluorescence emission of nanocomposites depends on the type of fluorescent agent. The fluorescence intensity of nanofiber containing CQDs is more than nanofiber containing fluorescent dye. Various image-processing methods provide similar results for optical property of nanocomposites. Analyzing the LUT, the blue value of CQDs/PAN nanocomposite image was significantly higher than other nanocomposites. This was confirmed by other methods such as Fourier transform, color histogram and 3D topography of the electrospun nanofibers. According to analysis of colorimetric parameters, higher negative value of b* indicates bluer color for CQDs/PAN nanofibers than other nanocomposites. The obtained results indicate that the image-processing technique can be used to evaluate the optical property of fluorescent nanocomposite.

This study evaluates the optical properties of fluorescent nanocomposites by using image-processing techniques such as Fourier transform, color histogram, RGB profiles, LUT, surface plot and histogram analysis.