Prediction model of hand arm vibration exposure among hand-held grass-cutters in Malaysia

Prolonged exposures to hand-transmitted vibrations from grass-cutting machines have been associated with increasing occurrences of signs of occupational diseases related to the hand-arm vibration syndrome (HAVS). However, there are no specific processes available that cover the objective and subjective health cause-effects of the hand arm vibration risk factors during onsite operations. Most of the existing vibration control measures have not extensively integrated administration and engineering techniques to be utilized as health prediction screening models. Therefore, the main objectives of this study are to integrate the engineering and administration control approach for reducing HAVS among hand-held grass-cutting workers and to determine the significant correlation of the objective and subjective measurement variables of the Hand Arm Vibration Exposure Risk Assessment (HAVERA) on hand arm vibration symptoms and disorders. The study was conducted in two stages: evaluation of the HAVERA variables (Stage 1) and development of the health prediction cause-effect model of the HAVERA process using multiple linear regressions and feed forward neural network programming (Stage 2). For the onsite measurement, the daily vibration value depicted an exceeded exposure action value of 2.5 m/s2 for both hands; and experiences of any finger colour change were claimed by 80% of the 204 subjects. This shows that the HAVERA process provided a good indication of HAVS which are reported as vascular, neurological and musculoskeletal disorders. In the right and left hand prediction model development, the results of the neural network model demonstrated a higher reliability performance as compared to the linear model for hand grip strength and hand numerical scoring assessment. The prediction of the HAVERA model using the neural network method has been developed for monitoring health conditions due to hand-transmitted vibrations among hand-held grass-cutting workers in Malaysia

CFD Simulation Analysis of Non-Premixed Combustion using a Novel AxialRadial Combined Swirler for Emission Reduction Enhancement

Combustion industries for many decades dealing with the issues in reducing the emissions without affecting the performance of combustion. The present study aims to investigate the performance of swirler mechanism which combining between both axial and radial types to reduce emissions and increase the mixing process via the nonpremixed method. Each of axial and radial swirler consisted with 8 blades vane. Swirl angle for radial swirler is 35° and inclination angle for axial swirler is 15°. The swirler is designed using Solidworks software package and CFD analysis was then performed using ANSYS Fluent software package. The fuel used is liquefied petroleum gas (LPG) gas which contained 30% propane and 70% butane. The turbulence model standard kepsilon was used in this study. The result found that the combined swirler was capable to reduce CO emission as the complete reaction into CO2 component was higher. This is due to the broader region of temperature and higher velocity magnitude produced by the combined swirler. However, the maximum temperature result for axial swirler was higher than the combined swirler. As a recommendation, the inclination blade angle in the axial swirler of the combined swirler should be increased to increase the temperature value

Countrywide survey on ISO 9001-certified companies in Malaysian construction industry

This article reports part of the results collected from 100 ISO 9001-certified companies in the Malaysian construction industry for a PhD research. Construction industry has bad public image because of safety, delay and quality issues. This is due to extreme segmentation and fragmentation of the supply chain, which cause difficulties in managing quality in construction industry. Due to low quality and low productivity, there is a need to implement ISO 9001 quality management system. This article helps to address the lack of data and information identified by CIDB Malaysia by documenting the extent to which Malaysian construction companies are accredited with ISO 9001 certifications, summarising the motivations behind the pursuit for ISO 9001 certifications, investigating the reasons for firms to obtain and maintain ISO 9001 certifications status in their organisations, and reviewing the extent to which ISO 9001-certified companies have gained benefits through the implementation of ISO 9001 quality management system. The results reveal that companies in the Malaysian construction industry adopt ISO 9001 certifications mainly to enhance their competitive processes and competitive performance to enable them to operate more efficiently