Mohamad Nizam Yusof

Effect of knowledge management on growth performance in construction industry

Purpose – The purpose of this paper is to examine the relationship between knowledge management and growth performance of construction companies. Design/methodology/approach – In total, 600 questionnaires were sent to selected individuals in grade G7 construction companies. A total of 110 completed questionnaires were returned and deemed usable. The collected data were processed and analysed by partial least-squares (PLS) path modelling with SmartPLS 2.0 software. This technique was selected because it is appropriate for exploratory studies, such as the current one, where hypothesised relationships between variables have not been tested. Findings – The findings show a positive relationship between knowledge management and growth performance in construction companies. The results of this study are valuable in establishing a valid and reliable survey instrument, especially for construction companies. Practical implications – The results of this study can be can be utilised as a basis for strategic choices b...

Preliminary Investigation of an Up-Scaled Gamma-Type Stirling Engine for Power Production

This paper presents the development of Gamma-type Stirling engine for High Temperature Differential (HTD) and self-pressurized mode of operation. The engine is the up-scaled version from the Low Temperature Differential (LTD) miniaturized gamma-type Stirling engine. The test engine is featured with 85cc power piston and 4357cc displacer piston swept volumes, respectively. The characterization of few critical engine parameters and components that includes heater head section, cooler section, displacer and power pistons material selection and heat source system had been conducted. Air is used as a working fluid and Liquefied Petroleum Gas (LPG) is utilized as the heat source in order to cater for the heater temperature up to 1000°C. The workability test of the engine revealed that the lightweight in mass of the displacer piston and the auxiliary cooling effect at the cooler section had contributed to a significant improvement on the engine rotational motion. The static load test determined that the engine is capable of producing the friction power of 1.2W for stainless steel mesh wire displacer and 0.3W for polystyrene displacer. Based on Beale formula, the estimated power of 4W can be produced by the engine using stainless steel mesh wire displacer and 2.4W of power using polystyrene displacer. Good agreement has been shown, where the potential net power production of 3.8W and 2.1 W for stainless mesh wire displacer and polystyrene displacer, respectively. Further investigation is needed to improve the heat regeneration in between hot and cold sections of the engine to realize the sustainable performance of the engine at higher range of temperature difference and output power.

An Investigation of a Self-Pressurized Alpha V-Type Stirling Engine Converted Diesel Engine

This study reports the investigation results of 194cc. alpha V-type Stirling engine converted from a four-stroke diesel engine that operated in self-pressurized mode. Tests were conducted with air as the working gas and liquefied petroleum gas (LPG) as the heat source. The engine started operating at 600 °C for hot cylinder temperature and 60 °C for cold cylinder temperature, respectively. At heat input of 1100 J/s, the engine performance was successfully tested at both no load and load conditions. For mechanical shaft power assessment, the engine approximately produced a maximum brake power of 7 W, brake thermal efficiency of 0.6% at 717 rpm speed, 811 °C hot cylinder temperature and 96 °C cold cylinder temperature. For electrical power assessment, the engine was capable of generating a maximum electrical output power of 1.7 We at 657 rpm speed, 855 °C hot cylinder temperature and 98 °C cold cylinder temperature. Despite its low engine performance, the study of alpha V-type Stirling engine is a worthwhile step towards clean and sustainable energy in mass production.