Nurul Najwa Mansor
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Preferred name
Nurul Najwa Mansor
Official Name
Nurul Najwa, Mansor
Alternative Name
Mansor, Nurul Najwa
Mansor, N.
Mansor, N. N.
Main Affiliation
Scopus Author ID
56287878400
Researcher ID
FKT-9536-2022

Research Output

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DMAIC steps application to improve ergonomics problem: a case study in coffee manufacturing industry

2022 , Nurul Najwa Mansor , Shaliza Azreen Mustafa , R Badlishah Ahmad , Mohd Asyraf Che Doi , Tan Chan Sin , Mohd Asri Jusoh

The health issue related to Musculoskeletal Disorders (MSDs) faced by manufacturing industries’ workers affects the work quality and productivity, commonly due to the tasks performed with unsuitable posture. This study was carried out to assess the level of Ergonomics Risk Factors (ERFs) among shop-floor workers in a coffee manufacturing company, located in northern peninsular of Malaysia. The Six Sigma approach was applied based on Define, Measure, Analyze, Improve and Control (DMAIC) steps. Observation, interviews and self-report surveys were conducted in the Define step to identify the potential tasks that lead to the high level of ergonomics risk. In the Measure step, the Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA) tools were then used to assess the level of ERF on twenty-three tasks that practice at eight workstations. In the Analyze step, assessment results were evaluated, thus identifying that the lifting task (mixing workstation) has the highest ergonomics risk level (score level 11) and follows by root cause identification. Then, the Improve step focuses on a simple invention proposal, where the optimal solution that fulfills the principles of proper height working procedure and reducing excessive force is applied. The proposed solution shows a significant improvement in ergonomics risk level based on the score value of 3. Lastly, the Control step focuses on sustaining the improved version performance by revising the working procedure according to the solution principles proposed in the previous step.

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Methane Gas Production from different composition of Food Waste and Chicken Manure

2020-12-18 , Tengku Roslina Tuan Yusof , Maslinda Abu Bakar @ Yahaya , Nurul Najwa Mansor , Mohd Faiz M.S. , Hasfalina C.M. , Nor'Aini A.R.

High carbohydrate content in food waste is one of the characteristic suitable acted as a co-substrate for fermentation to produce methane gas. In this study, co-digestion of chicken manure (CM) and food waste (FW) was used for fermentation process in methane gas production. The different effects of the independent variables (ratio, pH and temperature) is the most significant parameters of methane gas fermentation of CM and FW were investigated. Based on the analytical study showed a good fit between the experimental and the predicted data as the R2 values of 0.991 with methane yield to be 537 mL CH4/g VS at ratio 80:20 (CM:FW); temperature 35 C; and initial pH 7.11 in 20 days of fermentation. The experiment was then performed based on optimized parameters of pH, temperature and ratio at the highest yield of methane obtained from optimum parameters. After optimization, the result showed that the pH 7.11 at 35 C temperature and the ratio of 80:20 with methane production yield of 1560.5 mL CH4/g VS for the 21 days of digestion process.

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Mechanical design and evaluations of new corn peeler design produced via three-dimensional printing technique

2020-11-02 , Muhammad Ikman Ishak , Khor Chu Yee , Siti Nor Azreen Ahmad Termizi , Norshamsuri Ali @ Hasim , Nurul Najwa Mansor

Traditionally, the corns are commonly peeled using knife or any other cutting tools to extract the kernels from the cob before the next processes taken place. However, most of those conventional methods are time-consuming, highly risked to injury as well as resulting in less output. Thus, a new method of corn peeling is necessary to obtain a more convenient and safe cutting technique in order to eliminate the existing drawbacks. A series of idea generation and concept development stages was hence undertaken to develop a new design of corn peeler. Then, the finalized concept was interpreted as a three-dimensional (3-D) model comprising three main parts namely body, handle, and container, in which designed using a computer-aided design (CAD) software. The CAD data was then exported into a 3-D printing software to print out the product. A computational finite element analysis (FEA) was performed on the product to evaluate its performance under simulated mechanical loadings. The pre-processing settings prior to the analysis were set as follow: 1) Element type: Four-nodes tetrahedral; 2) Mesh size: 3.0mm; 3) Material properties: Acrylonitrile butadiene styrene (ABS) (Young's modulus, E of 2.3GPa and Poisson's ratio, v of 0.35); 4) Load: 650 N/mm2 (pressure); and 5) Boundary conditions: The bottom surface of the container (fixed in all directions). The FEA results exhibited that the predicted mechanical stress generated within the proposed 3-D printed design model was satisfactorily to provide a convincing response. Moreover, an actual testing was also conducted among different corn peelers and the findings depicted that the proposed product promoted an increase up to 48.7 and 33.3% in peeling time and amount of kernels extracted, respectively. Therefore, the new design of corn peeler which produced through 3-D printing technique is evident to tackle the disadvantages of existing peelers, besides the low cost and rapid processing time offered by additive manufacturing methods without compromising the quality are significantly desirable.

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Mechanical and morphology of interwoven Kenaf/PALF hybrid composites at different fibre ratio

2020-12-18 , Maslinda Abu Bakar @ Yahaya , Nurul Najwa Mansor , Tengku Roslina Tuan Yusof , Mohd Shukry Abdul Majid

As the extension to the research involving woven and natural fibre hybrid composites, this study characterise the mechanical properties of natural fibre hybrid composites with different fibre ratio. Plain weaved kenaf/PALF composites with fibre weight ratio of 10/10, 15/15 and 20/20 are fabricated via the hand lay up technique using epoxy as the matrix. Tensile and flexural test are performed according to ASTM D3039 and ASTM D790 standards, respectively. Morphological structure of the fracture specimens were examine using the Scanning Electron Microscope (SEM). As a result, the 15/15 fibre ratio composite had the highest tensile and flexural strength. Addition of kenaf fibre improve the mechanical properties of the composites and increase the potential of PALF fibre as filler for future natural fibre applications.

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Magnetohydrodynamic (MHD) stagnation point flow and heat transfer towards a stretching sheet with suction in a Nanofluid

2014 , Nurul Najwa Mansor

The magnetohydrodynamic (MHD) stagnation point flow and heat transfer towards a stretching sheet in a nanofluid with suction is investigated. The basic equations governing the fluid flow and heat transfer are transformed into nonlinear ordinary differential equation using a similarity transformation, before being solved by means of a shooting method. The effects of suction parameter on the skin friction coefficient, the local Nusselt number and the local Sherwood number as well as the velocity and the temperature profiles are obtained and analyzed. The numerical results indicate that the magnitude skin friction coefficient, the local Nusselt number and the local Sherwood number increase with suction effect.

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Design and development of driving external support for lower limb disable patients

2020-12-18 , Nurul Najwa Mansor , Maslinda Abu Bakar @ Yahaya , Tengku Roslina Tuan Yusof , Ruslizam Daud

The driver who lower limb disabled patients were used the hand control to drive. The hand control was fixed permanently on the pedals. Thus, their family cannot share the car with them. Hence, there are several ways to innovate the hand control become portable product. This study was undertaken to investigate the characteristic driving behaviour of lower limb disabled patient yet to establish the design driving external support that was portable by using hand control. There are many types of mechanism that was used to upgrade the product function compare to existing product. The materials mainly used steel as the materials of hand control stick. The fabrication process was used two weeks to done the prototype. Using a novel upgrading of portable hand control may help the disable patient easily use the fingers and hand, without using any tools. This product also can be refit in others car. The innovation of mechanism assists patients can share their car with their family members.

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Finite element analysis of type-7 microcrack penetration induced by Haversian system

2018 , Nurul Najwa Mansor

An absolute and relative stability of fixation determine the optimum direct primary and indirect secondary bone healing process through bone remodelling and osseointegration. Clinically, under compression, shear and torsional loading condition, the stability of implant fixation is affected by insufficient, over supplied and inconsistent stress shielding transfer (SST) between implant-bone interfaces. At worst, SST mechanism may trigger the implant fixation failure, implant pins or screw loosening and anatomical bone fracture that initiated from bone damage by pre-drilled technique which enhance bone microcracks interface. The micromechanics elastic interaction of microcrack penetration into Haversian system initiated by pre-drilled microcrack is presently unexplained based on fracture mechanics principles. Therefore, this research aims to investigate the Type-7 single microcrack penetration into Haversian system for primary and secondary bone formation specific to diaphysis cortical bone transverse and longitudinal fracture. Linear elastic fracture mechanics (LEFM), elastic plastic fracture mechanics (EPFM) and Kachanov theory of elliptical hole and microcracks interaction are used to establish primary and secondary bone fracture model using finite element (FE) analysis. The FE algorithms were developed in ANSYS APDL environment to establish Mode I and Mode II Type-7 crack penetration model for all cortices in transverse and longitudinal direction by incorporating crack tip stress singularity approach using displacement extrapolation method (DEM) and stress energy release rate (SERR) using J-integral method. Both approaches are numerically analysed and verified with good theoretical agreement by Brown & Srawley (0.2%), Gross & Brown (0.4%) and Tada (1.6%) analytical formulation for single edge crack in finite body. Sensitivity and statistical analysis also show a significant correlation (p < 0.05) between measured parameters for all cortices. Type-7 penetration model is further enhanced for primary bone cracking evaluation. Both DEM and J-integral method have accurately determined the Mode I (KITS(A,P,M,L), KILS(A,P,M,L)) and Mode II (KIITS(A,P,M,L), KIILS(A,P,M,L)) SIFs but it seems the only J-integral able to evaluate the influence of different Young‟s modulus in primary bone cracking. Thus, for secondary bone cracking, only J-integral analysis is further enhanced to evaluate the inhomogeneity of Haversian system interaction to drive the transverse and longitudinal Type-7 microcrack penetration through interstitial matrix, cement line and osteon induced by Haversian canal stress traction. The quantification of stress amplification σSA, stress shielding σSS and stress traction are evaluated and verified by analytical formulations and Kachanov theory of elliptical crack and microcrack interaction. The results show that in transverse (KITS/K0) >1 and longitudinal (KILS/K0) >1, σSA is dominated in interstitial matrix area. Transition of σSA to σSS is occurred upon the cement line penetration and in osteon to Haversian canal penetration, the penetration is driven by σSS at (KITS/K0) <1 and (KILS/K0) <1. However, both transverse and longitudinal Type-7 direction experienced different intensity and energy release rate of σSA to σSS upon cement line penetration in relative to crack-to-width ratio (a/W). In conclusion, the Haversian system interaction model has successfully demonstrated the Type-7 microcrack penetration for primary and secondary bone formation.

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A review of factors influencing peri-implant bone loss

2021-07-21 , Muhammad Ikman Ishak , Ruslizam Daud , Ishak Ibrahim , Fauziah Che Mat , Nurul Najwa Mansor

Dental implants report high survival rate for the treatment of patients with missing teeth and being one of the undeniable restoration techniques. However, peri-implant bone loss has recently arisen to be the highlight in contemporary implant therapy. Therefore, the possible causes that are detrimental to dental implants and surrounding tissues are important to be discovered. The present review focuses on the current etiologies of peri-implant bone loss and subsequent complications observed in clinical practices. A comprehensive literature search was conducted via PubMed, Scopus, and ScienceDirect databases using the related keywords. The literature reveals numerous etiological factors may initiate the loss of marginal bone in dental implant application: loading protocols, implant body placement, implant macro-design features, implant surface roughness, implantation site preparation, foreign body reaction, implant material particles detachment and contamination, and oral habit. Albeit the biomechanical, biological, or combination of factors are known to contribute in marginal bone resorption, the predictability of treatment modalities to handle the defect remains controversial and unclear. Further clinical trials and sophisticated quantitative assessment would be advantageous to help scrutinize the issue.

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Optimization of Two-Dimensional Finite Element on Primary Bone Type-7 Fracture Model

2020-09-21 , Nurul Najwa Mansor , Muhammad Ikman Ishak , Ruslizam Daud

Optimization works is an important method for Finite Element (FE) analysis to get better accuracy in simulation study before proceed for further analysis. In this present work, convergence study of local crack tip meshing involving radius of first row element, a/n (DELR) and number of crack tip element (NTHET) is employed on single edge crack in homogenous properties of human cortical bone. Mode I and Mode II Type -7 penetration were determined by using FE analysis and compared with the experimental results. Based on the results, a good agreement is found between numerical and experimental results. The first section in your paper

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