Mohd Nasrull Abdol Rahman

Investigation of work-related musculoskeletal disorders in wall plastering jobs within the construction industry

OBJECTIVE The aim of this study was to investigate the work-related musculoskeletal disorders (WMSDs) among workers in wall plastering jobs within the construction industry. PARTICIPANTS A total of 43 workers within three workplaces participated in the study. METHODS Subjects were interviewed using self-report charts. During the task duration, observation of the workplace was carried out using a Workplace Ergonomic Risk Assessment (WERA) method. RESULTS An analysis of WERA assessment, the wrist score for WERA body part was >4 in 86% of workers, while wrist pain or discomfort was reported by 86%, yielding a significant association between WERA body part score and self-reported pain (χ(2)=16.12; p=0.000). The WERA body part score for the shoulder regions during wall plastering job yielded a score > 4 in 93% and caused shoulder pain or discomfort in 91%, the association being significant (χ(2)=12.58; p=0.000). The back regions for WERA body part score was >4 in 91% of workers, with 98% reporting pain or back discomfort, with a significant association (χ(2)=9.98; p=0.002). CONCLUSIONS These results showed that statistically significance for the wrist, shoulder and back regions of the individual WERA body part scores were affecting the worker and lead to the development of pain or discomfort among workers in wall plastering jobs.

Review on pen-and-paper-based observational methods for assessing ergonomic risk factors of computer work

BACKGROUND Computer works are associated with Musculoskeletal Disorders (MSDs). There are several methods have been developed to assess computer work risk factor related to MSDs. OBJECTIVE This review aims to give an overview of current techniques available for pen-and-paper-based observational methods in assessing ergonomic risk factors of computer work. METHODS We searched an electronic database for materials from 1992 until 2015. The selected methods were focused on computer work, pen-and-paper observational methods, office risk factors and musculoskeletal disorders. This review was developed to assess the risk factors, reliability and validity of pen-and-paper observational method associated with computer work. Two evaluators independently carried out this review. RESULTS Seven observational methods used to assess exposure to office risk factor for work-related musculoskeletal disorders were identified. The risk factors involved in current techniques of pen and paper based observational tools were postures, office components, force and repetition. From the seven methods, only five methods had been tested for reliability. They were proven to be reliable and were rated as moderate to good. For the validity testing, from seven methods only four methods were tested and the results are moderate. CONCLUSION Many observational tools already exist, but no single tool appears to cover all of the risk factors including working posture, office component, force, repetition and office environment at office workstations and computer work. Although the most important factor in developing tool is proper validation of exposure assessment techniques, the existing observational method did not test reliability and validity. Futhermore, this review could provide the researchers with ways on how to improve the pen-and-paper-based observational method for assessing ergonomic risk factors of computer work.

Effect of triggering angles on the crushing mechanisms of hybrid woven kenaf/aluminum hollow cylinders

This paper presents the effect of triggering angles constructed on the top of hybrid woven kenaf/aluminium hollow cylinders on the energy absorption performances. The crushing performances of aluminium tubes can be found widely in open literature. However, lack number of work on the hybridizing the aluminium tubes with woven kenaf fibre is found. Woven kenaf mats are produced and bathed with polymeric resin before they are wrapped around the aluminium tubes twice. Different fibre orientations, +-θ° are used where θ = 0, 15, 30 and 45. Once the hybrid composite hardened, one of their end are chamfered using different angles of 0o, 30o, 45o and 60o. The tubes are quasi-statically compressed in order to obtain their force-displacement responses and crashworthiness parameters are extracted and discussed with the relation of fibre orientations and chamfering angles. It is found that the chamfering angles are only affected the force-displacement curves during the first stage of elastic deformation whereas there is no obvious effect in the second stage. However, varying the fibre orientations are slightly increased the force-displacement curves especially when the fibre is orientated with 30o. Based on the fracture mechanism observations, most of composite experienced large fragmentation indicating that the composites absorbed the crushing energy ineffectively.

An Evaluation of Mechanical Properties on Kenaf Natural Fiber/Polyester Composite Structures as Table Tennis Blade

Nowadays, natural fibers getting attention from researchers and industries to optimize the use it, with combination of polymers as composite structure, due to environmental awareness. Furthermore, it show a few advantage, such as biodegradability, light in weight and non-toxic characteristic. In this study, kenaf natural fibers was used as reinforcement material, with combination of polyester as matrix material, known as polymer matrix composites. The main purpose of this study is to analysis the mechanical properties of kenaf natural fiber/polyester composite structure, in order to know the suitability of kenaf natural fibers as replacement material for table tennis blade structure, instead of using wood. The structural panel of composite laminates has been produced using hand lay-up technique. The experimental works are performed in tension, impact (Charpy) and shear condition. The characteristic of different condition on kenaf composite structure was studied. Based on the result, it found the properties of kenaf composite structure, and it will used as a benchmark, to compare with initial properties of table tennis blade made by wood. In addition, the strength and a weakness of that particular materials and lamination structure will be identified.

Improvement of automatic fish feeder machine design

Nation Plan of action for management of fishing is target to achieve an efficient, equitable and transparent management of fishing capacity in marine capture fisheries by 2018. However, several factors influence the fishery production and efficiency of marine system such as automatic fish feeder machine could be taken in consideration. Two latest fish feeder machines have been chosen as the reference for this study. Based on the observation, it has found that the both machine was made with heavy structure, low water and temperature resistance materials. This researchs objective is to develop the automatic feeder machine to increase the efficiency of fish feeding. The experiment has conducted to testing the new design of machine. The new machine with maximum storage of 5 kg and functioning with two DC motors. This machine able to distribute 500 grams of pellets within 90 seconds and longest distance of 4.7 meter. The higher speed could reduce time needed and increase the distance as well. The minimum speed range for both motor is 110 and 120 with same full speed range of 255.

PCL/PLA Polymer Composite Filament Fabrication using Full Factorial Design (DOE) for Fused Deposition Modelling

In this study, Polycaprolactone / Polylactice Acid (PCL/PLA) composite are used to fabricate filament wire with the specific diameter, which is in the range of 1.75 to 1.80 mm. Full factorial experimental design technique was used to study the main effects and the interaction effects between operational parameter which is (A) die temperature, (B) roller puller speed, (C) spindle speed and (D) inlet temperature. Besides that, there are two levels (-1 and +1) and the response are filament wire diameter. There are 16 numbers of runs and plus 8 centre points per blocks which makes the runs into 24 runs. From the experiment it shows that there are four factor that are significant effects on the filament wire diameter which is A, B, C and BC. The optimum parameter setting are also determined and there are 10 suggestions to achieve the target with different setting of parameter. The margin error for confirmation run is below than 15% when the parameter set at 6 Hz spindle speed, 4.99 rpm roller puller, 100.31 °C die temperature and 79.65 °C inlet temperature which can be noted that the confirmation run result is acceptable. The optimization parameter setting can use to continue in Fused Deposition Modelling (FDM). Filament wire from PCL/PLA are succesfully fabricated with acceptable diameter size and ready to be used for Fused Depotion Modelling process (FDM).

Programme Learning Outcomes Assessment and Continuous Quality Improvement in Faculty of Mechanical and Manufacturing, UTHM

This paper describes the assessment and continuous quality improvement of Programme Learning Outcomes (PLOs) in the Faculty of Mechanical Engineering and Manufacturing. PLO is known as an elementary requirement in Outcome Based Education (OBE) system. All PLOs have been mapped with graduate attributes by EAC Manual 2012. Conceptual process for establishing and reviewing PLOs has been explained in the Plan-Check-Do-Act cycle. PLO assessment has been shown in different types which classified as direct and indirect methods. Continuous Quality Improvement has been extracted from a variety of assessment and has been discussed. Seven (7) CQIs are identified using different assessment methods of PLO during years 2013 to 2016 and subsequent improvement actions have been taken by the faculty within three years.

Characterization and Mechanical Analysis of PCL/PLA composites for FDM feedstock filament

In this research, characterization, and the mechanical properties of Polycaprolactone (PCL) and Polylactic Acid (PLA) composites with the objective of determining their suitability as biomaterials for an alternative composites material for Fused Deposition Modelling (FDM) was investigated. The percentage of PLA is varies from 10% to 50% by weight. The PCL/PLA composites were prepared by melting and mixing using Brabender Plastograph machine. The characterization of PCL/PLA composites was characterized using Fourier Transform Infrared (FTIR). Meanwhile, the mechanical properties were evaluated are the Tensile, Flexural and Impact. It demonstrate that by the addition of PLA it improve the mechanical properties of PCL and leads to a better processability of PCL/PLA composites. With the decrement of PLA content in PCL/PLA composites the Tensile Strength the Youngs Modulus and also the Impact Strength of the composites increased. The highest tensile strength was recorded at 10.00 Mpa and the Youngs Modulus was recorded at 118.26 Mpa. The highest Impact Strength was recorded at 1.33 J. However, the Flexural Strength and Flexural Modulus increased when the content of PLA decrease and it slightly drop when the content of PLA is at the 40%. The highest Flexural Strength and Flexural Modulus were recorded at 7.59 Mpa and 35.33 Mpa respectively. Overall it can be concluded that the PCL70PLA30 composites are the best formulation and it gives a better mechanical properties result.

Musculoskeletal symptoms and ergonomic hazards among material handlers in grocery retail industries

Grocery retail work can be physically demanding as material handlers tasks involve manual lifting, lowering, carrying, pushing and pulling loads. The nature of this work puts them at a risk for serious low back pain, shoulder pain and other musculoskeletal injuries. This study was conducted by using two different types of tools which were Nordic Musculoskeletal Questionnaire (NMQ) as a survey and Washington Industrial Safety and Health Act (WISHA) Checklist as a direct observation method. Among 46 males and 14 females material handlers were involved throughout this study. For NMQ, the highest body part trouble in the last 12 months was low back pain (88.3%), followed by upper back (68.3%), neck (55.3%) and shoulder (36.7%). While for WISHA Checklist, most of them experienced hazard level involving awkward posture and high hand force. From the research conducted, musculoskeletal disorders (MSDs) and ergonomic risk factors (ERFs) do related as it showed that musculoskeletal disorders may arise if the workers ignored the safety in ergonomic hazards.

Exposure level of ergonomic risk factors in hotel industries

Ergonomic Risk Factors (ERFs) which contribute to Musculoskeletal Disorders (MSDs) among room attendants were considered as a problem or trouble since these ERFs would affect their work performance for hotel industries. The purpose of this study was to examine the exposure level of ERFs among room attendants in hotel industries. 65 of respondents were obtained from selected hotels in Peninsular Malaysia. Data were collected by direct observation via Workplace Ergonomic Risk Assessment (WERA) and Quick Exposure Checklist (QEC). There were 36 males and 29 females room attendants involved throughout the research. Most of room attendants experienced high exposure level for back, leg, forceful and vibration based on the exposure level evaluation through WERA while QEC results showed that all room attendants were found to have moderate exposure level for risk factors including back for movement use, shoulders/arms, wrists/hands and neck. All the results obtained showed that the related ERFs for MSDs were associated and essential ergonomic interventions are needed in order to eliminate risk of exposures to MSDs among room attendants in hotel industries.