Two imines of different molecular sizes namely 3-(phenylimino) indolin-2-one (PII) and 3,3- (1,4-phenylenebis (azan-1-yl-1-ylidene) diindolin-2-one (PDI) were investigated for their corrosion inhibition on mild steel in 1 M HCl solution using electrochemical impedance spectroscopy (EIS). The bigger molecule PDI containing double the amount of isatin moiety exhibited higher inhibition efficiency of 87.3% while PII that contained monoisatin moiety showed a lower inhibition efficiency of 74.8%. Both compounds had an increase in inhibition efficiencies percentage as concentrations increased. Density functional theory (DFT) was used to determine the correlation between the corrosion inhibition efficiency and electronic parameters. The DFT calculations indicated that the corrosion inhibition efficiency was mainly dependant on the frontier orbital energy gap and the chemical softness/hardness of the imines.
This paper proposes a 3D object recognition method based on 3D SURF and the derivation of the robot space transformations. In a previous work, a three fingered robot hand had been developed for grasping task. The reference position of the robot hand was programmed based on predetermined values for grasping two different shapes of object. The work showed successful grasping but it could not generate the reference position on its own since no external sensor was used, hence it is not fully automated. Later, a 2D Speed-Up Robust Features (SURF) and 3D point cloud algorithm were applied to calculate the object’s 3D position where the result showed that the method was capable of recognising but unable to calculate the 3D position. Thus, the present study developed 3D SURF by combining recognised images based on 2D SURF and triangulation method. The identified object grasping points then are converted to robot space using the robot’s transformation equation which is derived based on dimensions between robot and camera in the workplace. The result supported the capability of the SURF algorithm for recognising the target without fail for nine random images but produced errors in the 3D position. Meanwhile, the transformation has been successful where the calculated object positions are inclined towards the directions of actual measured positions accordingly related to robot coordinates. However, maximum error of 3.90 cm was observed due to the inaccuracy of SURF detection and human error during manual measurement which can to be solved by improving the SURF algorithm in future.
This paper presents adaptive particle swarm optimization for solving non-convex economic dispatch problems. In this study, a new technique was developed known as adaptive particle swarm optimization (APSO), to alleviate the problems experienced in the traditional particle swarm optimisation (PSO). The traditional PSO was reported that this technique always stuck at local minima. In APSO, economic dispatch problem are considered with valve point effects. The search efficiency was improved when a new parameter was inserted into the velocity term. This has achieved local minima. In order to show the effectiveness of the proposed technique, this study examined two case studies, with and without contingency.
MeSH terms: Artificial Intelligence; Problem Solving
Iris recognition has become a widely popular biometric system. The stable textures and features of the human iris have made such biometric systems efficient and accurate for purposes of verification and identification. The term non-ideal iris refers to a situation in which the iris is occluded by noise, including reflections, eyelashes, eyelids and so on. Most current iris recognition algorithms assume that the iris is not occluded, which is less accurate. A method using only some parts of the iris may be suitable to deal with a non-ideal iris. The current application of iris recognition systems are plagued by weaknesses such as slow processing times, especially when dealing with many irises. In this study, a sub-iris recognition technique is proposed to deal with the non-ideal iris, while reducing execution time via an embedded system using a graphical processing unit (GPU). The experiment revealed that the proposed method was accurate and fast.
Islam is the fastest growing religion in the world. The number of the Muslim worldwide has been increasing through birth and conversion rate. As the number of Muslim population grow so does that the demand for halal product worldwide. While quality is seen as an integral part of related companies ‘strategic business plan. Leadership is difficult to characterise and it implies different things to various individuals. However, it is considered as a noteworthy driver for the TQM practices. This paper examines Lean Manufacturing (LM), Total Quality Management (TQM), Environmental Management System (EMS) and Islamic Manufacturing practices (IMP) and explores the possibility to integrate this management system into a new Islamic model for in the Malaysian food industry as the country moves forward to becoming a Halal Hub Country. This is a conceptual study, and provides a foundation for future research on this topic.
Clustering refers to reducing selected features involved in determining the clusters. Raw data might come with a lot of features, including unimportant ones. A hybrid similarity measure (discovered in 2014) used in selecting features can be improvised as it might select all the attributes, including insignificant ones. This paper suggests Fuzzy Lambda-Max to be used as a feature selection method since Lambda-Max is normally used in ranking of alternatives. A set of AIDS data is used to measure the performance. Results show that Fuzzy Lambda-Max has the ability to determine criteria weights and ranking the criteria. Hence, feature selection can be done by choosing only the important criteria.
In recent years, injection moulding process is one of the most advanced and efficient manufacturing processes for mass production of plastic bottles. However, a good quality of parison is difficult to achieve due to uncontrollable humidity, pressure inlet and water inlet velocity. This paper investigates the effect of using multiple mould cavities to improve the process fill time and injection pressure in the production of PET plastic bottles using MoldFlow software. The modelling of parison was developed using CATIA with the consideration of every part of the parison. MoldFlow software was used to analyse the flow of 20 g parison with different cavity numbers (1, 8, 16, 24 cavity), as well as its corresponding runner size towards its fill time and injection pressure. Other important parameters that affect the production of parison, such as melting temperature, mould temperature, atmospheric temperature and cooling time, were remained constant. The fill time required to produce 24 moulds was improved by 60% compared to using 8 mould cavity only, and this enable the production of more plastic bottles in a day. Therefore, fill time and injection pressure are two important parameters to be considered in the injection moulding process, especially to reduce parison defect and increase its production rate.
Aluminium foam tube is a metal that consists of porous medium with special characteristics such as good energy absorption, good heat transfer and high thermal conductivity. These make it suitable to be used in a wide range of applications such as in heat exchangers. The aim of this project is to identify and analyse mechanical behaviour and microstructure aluminium foam tube produced and fabricated with infiltration method with vacuum-gas. The density of aluminium foam tube was also determined and an average aluminium foam tube with porosity 50% - 80% with the average NaCl particle size 2mm, 3mm and 4mm was produced. Foams with porosity 60%-75% NaCl has higher energy absorption. These was based on foam structure, density and maximum compressive load test result.
This paper investigates the effect of acid and silane treatment of Carbon Nanotubes (CNT) on wear properties of epoxy polymer composite. The wear test done was based on ASTM D3389 standard using the Abrasive Wear Tester (TR 600). Characterisation analysis was also done using Transmission Electron Microscopy (TEM) in order to study the dispersion of the CNT inside the epoxy matrix. When untreated CNT was added to the epoxy with amounts of 0.5, 0.75 and 1.0 wt%, the wear rates did not improve except for 0.5 wt% CNT filled epoxy. This was due to the lack of dispersion which causes larger chunks of material being dug out, thus contributing to a higher mass loss and wear rate. When treated with acid and silane, 0.75 wt% and 1.0 wt% CNT filled epoxy composites showed improvement. The TEM images of 0.5 wt%, 0.75 wt% and 1.0 wt% PCNT filled epoxy supported the claim of the lack of dispersion of PCNT inside the epoxy.
This research investigated the wear properties of Carbon Nanotube (CNT) filled epoxy polymer and fiber reinforced composites. The CNT/epoxy composites with 0.5 wt% and 1.0 wt% CNT contents were mixed at 50°C for 1 hour at a speed of 400 rpm using mechanical mixer, while woven glass fiber reinforced polymer (GFRP) nanocomposites were fabricated using vacuum bagging technique. The effect of CNT on wear properties was evaluated using dry sliding abrasion wear test that used vitrified bonded silicon carbide as abrasive wheels. The mass loss and specific wear rate curves show that wear properties of epoxy polymer and GFRP composite systems were enhanced when CNT was added. Epoxy polymer and GFRP nanocomposites showed the highest wear resistance when CNT content was 1.0 wt% and 0.5 wt% respectively. The CNT-filled composite showed improvement till up to 78.9 % from its pure system. This suggested that the load transferability between CNT and epoxy was more effective in nanomodified systems than in its pure systems. Therefore, adding CNT improves the wear properties of epoxy polymer and woven GFRP composite.
In the electrodeposition system, adding saccharin alters the properties of the metal deposits by changing the electrode kinetics of the deposited surface. In this study, nanocrystalline cobalt-iron (CoFe) coating was synthesised using the electrodeposition technique with different saccharin concentrations. The results obtained showed that the coating thickness increased while the grain size decreased from 51 nm to 40 nm when the saccharin concentration increased from 0 to 2 g/L. The nanocrystalline CoFe coating produced with 2 g/L of saccharin concentration resulted in the smallest particle size of 71.22 nm and the highest microhardness of 251.86 HV. From the salt spray test (24 and 48 hours) it was found that the use of saccharin at higher concentration of 2 g/L improves the corrosion resistance of the nanocrystalline CoFe coating significantly due to the change of surface morphology as well as the decrease in grain size.
Solid polymer electrolyte based on methyl cellulose (MC)-lithium triflate (LiCF3SO3) plasticised with ethylene carbonate (EC) was prepared using solution cast technique. The X-ray diffraction (XRD) studies proved that the amorphous nature of the electrolyte systems was increases due to the addition of salt and plasticiser. The improved surface morphology of plasticised polymer system ensures it has good electrode-electrolyte contact during performance testing. The polymer electrolyte was found to have high thermal stability indicating that the electrolyte can be used at higher temperature. The ionic conductivity increased up to 1.24 x 10-4 S cm-1 at optimum amount of EC plasticiser associated to the effect of plasticiser that initially leads to the formation of Li+-EC complex. Consequently, it reduces the fraction of polymer-Li+ complex which contributes to the increase of the segmental chain flexibility in the plasticized system. Temperature dependent studies indicate ionic conductivity increase due to the temperature increase and is in line with Arrhenius behaviour pattern. An activation energy of 0.26 eV at highest conductivity sample was obtained. The addition of plasticiser lowers the activation energy thus increasing the ion mobility of the system and contributing to ionic conductivity increment. The plasticization method is a promising means to dealing with the solid polymer electrolyte problem and producing electrolytes that meet the needs of electrochemical devices.
In this study, pressurized liquid extraction (PLE) was used with methanol as extraction solvent to extract bioactive compounds from Ananas comosus (pineapple) flesh. Response surface methodology (RSM) was used to evaluate the correlative effects of temperature (60 – 150°C) and extraction time (10 – 30 min) on the yield of selected bioactive compounds. In this model, the R2 obtained was 0.8788 for selected bioactive compounds for Ananas comosus suggesting a satisfactory agreement between the predicted and experimental values. Two-dimensional high-performance liquid chromatography (2D-HPLC) with a diode array detector (DAD) was used for the separation and detection of the bioactive compounds. Extraction temperature was found to significantly increase the yield of three selected bioactive compounds following which the optimum operating extraction conditions for PLE for Ananas comosus was determined to be 105°C and a static time of 20 min.
Headspace solid phase microextraction (HS-SPME) was used to isolate volatile compounds (VOCs) from mangoes (Harumanis cv.). Among the four SPME fibres investigated, the mixed phase coating, 65 μm polydimethyl siloxane–divinylbenzene (DVB/PDMS) showed the highest efficiency in extracting VOCs as 26 compounds were detected with the total area of 9.6 x 109. The optimization of SPME factors was conducted in 2 stages using multivariate design. The first stage involved screening of the significant factors using the Plackett–Burman (P–B) design, followed by the optimization of the significant factors utilizing Central Composite Design (CCD). The experimental design for both P-B and CCD design was generated using Design-Expert version 6.0.4 (Stat Ease Software). Extraction time and temperature appeared to be the most significant factors in extracting VOCs in mangoes, with the optimum conditions prevailing at 55°C and 34 minutes respectively.
Heavy metals from mining sites can contribute to adverse health and environmental issues. Conventional liming practice depletes natural limestone deposits. Blood cockle shell (BCS) and palm kernel shell (PKS) calcination produced alkaline ash to immobilize heavy metals in soil. This study investigates the acid neutralizing capacity (ANC) of calcined BCS and PKS composites. BCS and PKS composites were prepared at various weight ratios (i.e. 1:0, 1:1, 1:5, 1:10, and 0:1) and were combusted for 1 hour at 400°C and 900°C, respectively. BCS and PKS composites were determined by its yield, pH, and ANC. The combustion characteristics for composites was conducted using thermogravimetric analysis (TGA). Elemental analysis was conducted using X-ray fluorescence (XRF) spectroscopy. Fourier transform infra-red (FTIR) was conducted for functional groups analysis. Ash content of composites increased when the portion of PKS feedstock is decreased. Increasing combustion temperature from 400°C to 900°C reduced the ash contents. The pH of raw and combusted composite (at 400°C) decreased as the portion of PKS feedstock is increased. Calcined composites at 900°C have slightly different pH value except for 0:1 sample. ANC value increased as PKS portion in composites reduced. Higher content of calcium oxide (CaO) in the composites increased the ANC value.
The purpose of this study is to assess the performance of allied health personnel, after attending a training programme, in conducting vision screening for preschool children. A total of 43 allied health personnel (20 assistant medical officers (AMOs) and 23 nurses) attended a two-day training program prior to conducting vision screening for preschool children. Vision screening was conducted among 136 preschool children using four similar HOTV visual acuity chart at 6 m. The cut-off referral criterion for visual acuity (VA) testing was 6/9 or worse in either eye. All children were referred to two qualified optometrists for a comprehensive eye examination. The accuracy was based on the sensitivity and specificity of screening by each group of personnel. The overall prevalence of reduced VA in the studied population was about 10%. The sensitivity and specificity of vision screening performed by AMOs were 100% and 98% respectively while that performed by nurses were 56% and 94% respectively. Thus, there were discrepancies in the sensitivity of visual acuity testing despite them being conducted by healthcare providers with similar background and training. This suggests that their performance might be influenced by factors other than their professional training.
MeSH terms: Allied Health Personnel; Child, Preschool; Humans; Referral and Consultation; Vision Disorders; Visual Acuity; Vision Screening; Prevalence; Optometrists
The selection of curve number to represent watersheds with similar land use and land cover is often subjective and ambiguous. Watershed with several soil groups further complicates curve number selection process while wrong curve number selection often produces unrealistic runoff estimates. The 1954 simplified Soil Conservation Services (SCS) runoff model over-predicted runoff with significant amount and further magnified runoff prediction error toward higher rainfall depths in this study. The model was statistically insignificant with the rejection of two null hypotheses and paved the way for regional model calibration study. This paper proposes a new direct curve number derivation technique from the given rainfall-runoff conditions under the guide of inferential statistics. The technique offers a swift and economical solution to improve the runoff prediction ability of the SCS runoff model with statistically significant results. A new rainfall-runoff model was developed with calibration according to the regional hydrological conditions. It out-performed the runoff prediction of the simplified SCS runoff model and the asymptotic runoff model. The derived curve number = 89 at alpha = 0.01 level. The technique can be adopted to predict flash flood and forecast urban runoff.
MeSH terms: Animals; Birds; Calibration; Soil; Water Movements; Floods; Hydrology
An agricultural waste, the cocoa pod husk was chemically modified using a dehydrating agent, zinc chloride (ZnCl2), carbonised and used for the remediation of acid dyes in an aqueous solution. The targeted acid dyes are: (i) Acid Violet 17 (AV17); (ii) Acid Yellow 36 (AY36); and (iii) Acid Blue 29 (AB29). The physicochemical properties of the zinc chloride-modified cocoa pod husk-based carbon (ZCPHC) were characterised by ash content, bulk density, pH slurry, pHpzc and Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-Ray (EDX) analysis. The bulk density and ash content of the prepared carbon is 0.55 g cm-1 and 7.0% respectively. The photograph of SEM shows distinct changes at the ZCPHC carbon surface as it has large pores formed due to ZnCl2 modification. The adsorption tests were performed in a batch adsorption system using an aqueous solution of the understudy acid dyes. The influence of pH and dose of an adsorbent on the acid dye uptake was investigated and discussed. The adsorption was in favour at acidic condition with maximum removal observed at pH 2. The removal efficiency of the aqueous acid dye solution increased with the increase in adsorbent dosage. The kinetic experiment showed equilibrium time is less than 40 minutes and the kinetic data for all three understudy acid dyes fitted well with the pseudo-second-order model with a correlation coefficient (R2) values above 0.98.
This study examined the presence and sources of 10 pharmaceuticals in Klang River were studied. The most common pharmaceuticals were caffeine and acetaminophen, 0.57-20.62 ng/mL and “not detected”-1.45 ng/mL. Water samples were clustered based on pharmaceutical concentrations. Source apportionment analysis showed that treated wastewater discharged from treatment plants contributed 18.43% of pharmaceuticals in Klang River. An environmental risk assessment by means of the risk quotient (RQ) was done whereby the latter was more than one for salicylic acid and diclofenac in surface water posing threats to the aquatic environment. Salicylic acid showed high risk for acute toxicity, while diclofenac showed high risk for chronic toxicity. The results indicated a need for regular monitoring on pharmaceutical levels in Klang River and increasing the efficiency of wastewater treatment here.
Spin coated polyvinlylidenefluoride-trifluoroetylene (PVDF-TrFE 70/30mol%) copolymer thin film were initially produced and annealed at varying temperatures (100°C to 160°C). The morphology, dielectric and ferroelectric analysis showed that PVDF-TrFE film annealed at 120°C produced the highest remnant polarization, Pr of 92 mC/m2, with orderly and grain-like shaped crystallites. The filled PVDF-TrFE, loaded with various volume percentages (1 – 7%) of Magnesium Oxide (MgO) nanofillers and then, annealed at 120°C, produced homogenous filler distribution with low agglomerates, especially for 3% PVDF-TrFE filled films. Moreover, the annealed PVDF TrFE/MgO(3%) generated the highest value of Pr in comparison to the other filled nanocomposite thin films. Most importantly, the saturation of hysteresis loop, Ps for annealed PVDF-TrFE/MgO(3%) film was relatively improved by 20% as compared to the unfilled annealed thin film. This study established that, 3% MgO loaded in PVDF-TrFE thin film and annealed at 120 °C demonstrated a stable ferroelectric thin film, closed to an ideal ferroelectric film, in which the ratio Pr/Ps for the film established a value approaching unity (value of 1).