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In this paper, a review of materials selection methods is presented. It initially discusses the importance of materials selection in various fields of scientific study particularly in engineering design. Various tools and methods for the selection of materials are reviewed. These include materials handbook, materials data‐bases, materials selection charts, artificial intelligence systems, and other computeraided materials selection systems.

The purpose of this paper is to present the review of natural fibre composites as well as a specific type of fibre, i.e., sugar palm fibre and its composites.

The approach of this review paper is to present previous work on natural fibres and their composites. Then a review of several important aspects such as history, origin, botanic description, distribution, application and characterisation of sugar palm tree, and its fibre is presented. Finally a review of properties and characterisation of sugar palm composites is presented.

Findings of this review include the potential application of natural fibres and their composites for engineering application, the use of sugar palm and its fibres, as well as the suitability of sugar palm composites in engineering application after conducting review of their performance and characterisation.

The value of this review is to highlight the potential of natural fibres, natural fibre composites, sugar palm, sugar palm fibres and sugar palm composites as materials for engineering applications.

This paper presents the simulation results of a glass fiber reinforced PA 6,6 composite automotive clutch pedal. The analysis is carried out using Moldflow Plastics Insight (MPI) software to investigate the effects of increasing gate number from 1 to 2 on temperature and pressure. The results of temperature show that for single gate, the temperature was 291.3 °C and for double gate was 292.3 °C. Double gates mold induce higher temperature due to longer runner length. Both designs revealed different hot spots locations indicating probable areas of excess shear heating. The results of pressure (end of fill), for the single gate it was 61.31 MPa and for double gate was 60.73 MPa. Double gates mold reduce the required injection pressure as well as pressure variation, hence a lower volumetric shrinkage. Lower injection pressure produces lower shear rate and shear stress level.

Specific responses of thermoplastic components are required when they are subjected to impact conditions to minimize the damage in human body. Hardness property gives material, high resistance to various kinds of shape change when force is applied. In this study, mechanical properties such as impact strength and hardness of banana pseudo‐stem (BPS) unplastisized polyvinyl chloride (UPVC) composites were determined. It was found that fibre loading of BPS filler could enhance the properties of the impact strength and hardness of BPS/UPVC composites. The results on the addition of acrylic modifier to the composites have been discussed.

In this paper, an intelligent knowledge‐based system (KBS) capable of assisting aircraft mechanics and engineers to deal with fault diagnosis of the turbo‐prop aircraft engine is presented. The KBS intelligent jet engine trouble‐shooting system (IJETSS) employs expert knowledge to act in a way similar to that of a human expert in an aircraft maintenance field by using if‐then rule‐based system. The major aim of the KBS of IJETSS is to generate rapid and precise engine fault diagnosis that can simulate the work of experienced aircraft maintenance mechanics and engineers. The developed system can also be useful for the inexperienced aircraft mechanics and engineers and can be used for training module for them.

Selection of the design concepts is one of the significant activities in product development process. Most of the products are usually failed due to inappropriate decision during the selection of the design concepts at the early stage of product development process. The determination of the greatest selection of design concepts at the conceptual design stage is a crucial decision due to a poor design concept which can never be compensated for by a good detailed design and it will implicate great expense of redesign cost. Analytical Hierarchy Process (AHP) is one available method in forming a systematic approach for a single decision maker or a group decision maker, is employed to solve such problem. In this paper, 7 design concepts of wheelchair designs were considered as a case study. The AHP through utilizing Expert Choice software was implemented to determine the most suitable design concept of wheelchair design at the conceptual design stage. The sensitivity analysis was performed to test the stability of the priority ranking and to increase the confidence in the selection of design concepts.

A thermosyphon solar water heating system with in‐tank auxiliary electric heater has been simulated according Malaysian hot water consumption profile using TRNSYS simulation program. The optimum value of a parameter is defined as the value which maximized the annual solar fraction of the system. This paper has a good deal of information concerning sizing of common components of thermosyphon solar water heater operated under certain condition (load volume, distribution profile and temperature). The results indicate that collector should be tilted at Ø + (→ 7° 37°) for all collector areas. Vertical storage tank has better performance in tropical climate (The average annual solar fraction for vertical was 88% and for horizontal was 82.9%).

The purpose of this paper is to investigate the fracture properties of hybrid woven bamboo (WB)/woven e-glass (EG) fiber composites with various layer arrangements. This paper utilized a specific type of bamboo species named Gigantochloa Scortechinii (Buluh Semantan).

In these experiments, unsaturated polyester, woven EG and WB fibers were prepared through the hand lay-up technique. The composite bamboo strips were prepared in 1.5 mm thickness. The strips are woven to make a single layer. The layer was then laminated into several thicknesses. The specimens were then characterized using compact tension fracture tests.

The fracture toughness of 12–14 MPa was obtained. These findings suggest that this hybrid bamboo composite provides superior fracture strength that is equivalent with steel alloy and is extremely a good alternative for reinforcing fibers to combat fracture failures of materials and structures.

In this paper, experimental determination of newly developed composite made of WB and woven EG is presented.

To design and fabricate a wear testing rig for a water pump impeller and to select a parameter that can be used to determine the wear rates of slurry pump impeller.

A wear equipment was designed and fabricated in this study that of main rotating shaft, supported by two ball bearings, and main electric motor bully mechanism for the rotational speed torque needed. An impeller made of cast iron was selected. The wear medium selected consists of solid particles and water. The tests were conducted by letting the impeller to rotate in slurry. The wear data collection are divided into impeller's weight loss, impeller's diameter loss, impeller blade's thickness loss, impeller's blade height loss and impeller's thickness change.

The major type of wear that takes place in this experiment is erosion. The weight loss of the impeller is due to the material removal from the impeller as result of erosion wear. The diameter loss of the impeller is attributed to the impingement of solid particles on the surface area. The surface topography under the microscope indicates that the region near the center of impeller encounters less wear compared to the region at the rim of the impeller.

From this study, among all the parameters studied, the height loss of impeller blades encounters the highest percentage of wear. This is useful for determining the running hours before the complete failure of the impeller for slurry and impeller types used in this study.

Construction labour productivity is of great interest to practitioners and researchers because it affects project cost and time overrun. This paper evaluates and ranks the importance, frequency and severity of project delay factors that affect the construction labour productivity for Malaysian residential projects.

A total of 100 respondents consisting of 70 contractors, 11 developers and 19 consultants participated in this study. The respondents were asked to indicate how important each item of a list of 50 project related factors was to construction labour productivity. The data were then subjected to the calculation of importat indices which enabled the factors to be ranked.

The five most important factors identified by them were: material shortage at site; non‐payment to suppliers causing the stoppage of material delivery to site; change order by consultants; late issuance of construction drawing by consultants; and incapability of contractors' site management to organise site activities. On the other hand, the five most frequent factors were: material shortage at project site; non‐payment to suppliers causing the stoppage of material delivery to site; late issuance of progress payment by the client to main contractor; lack of foreign and local workers in the market; and coordination problem between the main contractor and subcontractor.

The inferences drawn from this study could be used by the project managers to take account of these factors at an early stage, hence minimising the time and cost overrun.