If we were given a questionnaire of “How do we measure a researcher as a true scientist? with optional answers like (a) Having a good number of publications, (b) having attending numerous conferences, (c) with a high popularity as always appeared in mass media, and (d) good international networking and good public relations. Options (c) and (d) always come later after option (a) has been achieved, while option (b) can be simply achieved or abstract be accepted for presentation in any conference. Hitherto, publishing in any peer-reviewed journals carry a certain quality since they are highly subjected to peer review evaluation before the paper can be accepted for publication in a journal. Needless to say, those constructive comments given by the reviewers are very crucial in shaping our scientific understanding in our subject area rather than rejection experience (Yap, 2009). Having said so, option (a) will definitely be the best answer. The fact is that option (a) should not be argued whatsoever as the best answer [since publications speaks louder than anything else] and options (a), (b) and (c) are supplementary criteria to option (a) but they are not as vital as option (a). When we are asked ‘What is your scientific research performance or research output?’, the answer could always be ‘Having a good number of publications.’ Then, the next question forwarded is that ‘What is the quality and impact of your published papers to the scientific community?’ Of course, good and high impact factor journals always accept papers with high novelty in the subject area. Therefore, papers published in good journals are always highly cited and subsequently resulting in high impact (or citations) of the research done to the scientific community. However, the last question is sometimes very subjective and difficult to answer until h-index is introduced and discussed among the researchers. This paper aimed to discuss the h-index based on Elsevier’s Scopus database as an indicator of research achievement for young Malaysian scientists.
A Structural Equation Model (SEM) is often used to test whether a hypothesised theoretical model agrees with data by examining the model fit. This study investigates the effect of sample size and distribution of data (normal and non-normal) on goodness of fit measures in structural equation model. Simulation results confirm that the GoF measures are affected by sample size, whereas they are quite robust when data are not normal. Absolute measures (GFI, AGFI, RMSEA) are more affected by sample size while incremental fit measures such as TLI and CFI are less affected by sample size and non-normality.
Input-Output analysis provides important information about the structure of a country’s economy. The construction of input-output tables based on detailed census or surveys is a complex procedure requiring substantial financial outlay, human capital, and time. This is the main reason why Malaysia Input-Output (MIO) Table is produced and published on average once every five years. For policy makers past data is not seen as suitable for planning economic policies. The aim of this study is to compare RAS and Euro methods to project input-output tables for Malaysia. The data for the study are MIO table and Gross Domestic Product for the years 2000, 2005 and 2010. The RAS and Euro method were used to project the MIO table 2005 using MIO table 2000 and also projection of MIO table 2010 using MIO table 2005. The projection of I-O tables involved an intensive iterative procedure using Excel Visual Basic programming. The projection performance of RAS and Euro methods were assessed based on Mean Absolute Deviation (MAD), Root Mean Squared Error (RMSE) and Dissimilarity Index (DI). The results show that Euro method performed better than the RAS method in the projection of MIO table.
Compartmented Fluidized Bed Gasifier (CFBG), consisting of two compartments - the combustorand gasifier, uses air blown instead of pure oxygen for syngas production in bubbling fluidization mode, eliminating the need of air separation unit, and reducing the capital cost, thus distinguishes it from other traditional ones. Fluidization quality is a determining factor in the CFBG to guarantee its well-lifted behaviour. Previous study, without solid circulation at ambient conditions, brought to the fore the necessity of considering the effect of the minimum allowable effective diameter. The study was then performed in the CFBG cold physical model of 0.66m overall diameter (effective diameter for combustor and gasifier is 0.413m and 0.257m) to investigate the fluidization quality and compare it with the results obtained from the previous cold model of about 1.36 times smaller, but with the same compartmented ratio of 65:35. Different inert particles (river sand, quartz sand and alumina) were used, over a range of aspect ratios, for the aforementioned objective. The results showed that the fluidization quality in the gasifier has not been achieved and the degradation of fluidization quality in the combustor is still observed, notwithstanding the fact that the condition of the minimum allowable effective diameter has been met. The reduction of distributor free area, to increase the distributor pressure drop, showed a marginal effect on the quality. The effect of the minimum allowable effective diameter on fluidization quality in CFBG as well as the interplay of geometric and operational parameters require further studies be carried out. The fluidization quality of the binary mixture is also currently under investigation.
In this paper, optimum routing was developed based on the travel salesman method and integrated in ArcInfo GIS using linear programming. The results of the optimized travel distances and times for residential waste collection and routing to disposal site were used to calculate the number and type of required track collection, labour requirement, costing of waste collection and to determine the overall solid waste management efficiency through waste management operation research methods. The objective of the study was to optimize residential collection and hauling to disposal site through operation cost minimization for Petaling Jaya Municipality in the state of Selangor, Malaysia. The study determined that with optimized routes and recycling possibilities, the total cost of waste collections could be reduced from RM90,372 to RM20,967, with a reduction of 76.8%. It was also revealed that optimum routes might not necessarily be the shortest distance from point A to point B as travel time maybe high on short distances due to traffic congestion and the presence of many traffic lights. Techniques and methods developed using general GIS have proven effective in route optimization and allowed management of data to suit local conditions and limitations of waste management for the studied area. Thus, scenarios of travel distances, time and waste quantity value generated from the GIS enabled appropriate determination of the number of waste trucks and labour requirements for the operation and the overall calculation of costs of waste management based on the operation research methods used in the study.
Electrocoagulation has proven to be an effective method in the treatment of wastewater. This study evaluated the decolourisation of Palm Oil Mill Effluent (POME) using electrocoagulation (EC) batch reactor by utilising aluminium as sacrificial electrode. POME sample source from a final discharged pond at a palm oil mill was characterised for its colour, chemical oxygen demand (COD), pH, conductivity and turbidity; were found to be 2707 PtCo, 3909 mg/L, 7.63, 12.82 mS/cm and 755 NTU respectively. The respective effects of operating parameters such as pH (3 to 11), applied voltage (5 V to 20 V), plate gap (7.5 to 11.5 cm) and operating time (1 to 8 hours) were investigated. The decolourisation of POME was observed to increase with increasing voltage and operating time. Highest removal efficiency was observed at pH 5, 20 V applied voltage, 9.5 cm plate gap and at 8-hour operating time with colour removal efficiency of 89, 79, 78 and 64% respectively. From the findings, it can be concluded that electrocoagulation process using aluminium electrodes is a reliable technique for the removal of colour from POME.
The assumption when constructing a control chart is that the process parameters, i.e. mean and standard deviation, are known. Nevertheless, this assumption is not realistic in practical situations. In most of the application of a control chart, the mean and standard deviation are unknown and are estimated from an in-control Phase-I samples. When the process parameters are estimated, the control chart performs differently compared with the corresponding chart with known process parameters because of the variability of estimators. The usual practice to evaluate the performance of a control chart is to use the average run length (ARL). The ARL is the average number of samples plotted on a control chart before an out-of-control signal is detected. In addition, the expected ARL (EARL) is used as a performance measure for the random process mean shift. In this article, the performance of the side sensitive group runs (SSGR) chart with known and estimated process parameters are studied and examined in terms of ARL and EARL.
Bismuth chromium solid solutions, with a general formula Bi6-xCr2Oδ, where -1 ≤ x ≤ 2, were successfully synthesized via the conventional solid state method. The phases of the synthesized samples were determined by X-ray diffraction (XRD) analysis. The properties of single-phase compounds were characterized by using differential thermal analysis (DTA), thermal gravimetric analysis (TGA), AC impedance spectroscopy, and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The occurrence of phase transitions was confirmed by DTA and TGA, where a thermal event was observed by DTA at around 800oC. In addition, TGA studies also showed that there was a weight loss at around 800oC. Elemental analysis of Bi6Cr2O15 and its solid solutions by ICP-AES showed a good agreement between the expected value and the experimental value on the compositions, with no evidence of any systematic deviation from stoichiometric. Electrical properties of Bi6Cr2O15 and its solid solutions were investigated by using AC impedance spectroscopy from 300oC to 650oC. Ionic conductivity increased with the increasing temperature and bismuth content, and the best ionic conductivity was observed for Bi7Cr2O16.5. The activation energy (Ea) of Bi6Cr2O15 and its solid solutions were in the range of 1.22-1.32 eV.
Ocean sediments give information on the paleoclimatic evolution in the geological past which gives detailed information on both the age of the sediments and both paleoceanographic and paleoclimatic conditions during sedimentation. One possible way to date sediments is with 210Pb method which can be used to date sediments up to 100 years. In this study, two core samples labelled as JB15 and JB17 were collected using pledging corer, analysed and measured for the activity of 209Po and 210Po using the alpha spectrometer. Applying the methods, average sedimentation rates for JB15 and JB17 were calculated as 0.38 cmyr-1 and 0.43 cmyr-1, respectively. Assuming that the sedimentation rate values are accurate, this might imply that the sediments at the depth of 30 cm were deposited 70 years ago.
The incident of beach pollution in Batu Ferringhi in year 2014 has created a major concern over water
quality at the tourists’ haven. In order to understand advection and dispersion of pollutants in the area,
a coastal hydrodynamic model of Batu Ferringhi beach was developed in this study by taking into
consideration its wind, tide, coastal current and riverine runoff. The model was calibrated and validated
through observations from adjacent coastal monitoring stations. Simulation was then carried out to
investigate scenario of the constituent water quality which originates from the three rivers in the vicinity.
Results showed high concentrations of water quality parameters observed near the headland towards the
northeast of the study area, with intermittent patchy escape which may retain more than one-third the
initial concentrations, weighted by the river discharge. Even more worrying is that localised trapping of
up to three-quarter the initial weighted concentrations also occurs at the beach, owing to the interactions
between river flow and longshore current.
Resident’s vehicles in some institutions have to be registered to maintain traffic safety. Penalties should be imposed if residents break traffic rules. Most of the time, the vehicle owner’s information is difficult to access making the penalty registration process complicated. An effective penalty registration process is required to make the process easier for security officers to give notice to the residents who have committed traffic offenses. A mobile application is proposed to recognize vehicle owner information. The proposed application uses optical-character-recognition (OCR) technologies that can facilitate the process of recognizing vehicle’s registration number in order to obtain owner information and use the information to enrol the penalty. The proposed application recognizes the vehicle registration number or sticker serial number to access the owner information. For evaluation of the proposed application, a user study was conducted by asking the users to use the application and answer the questiuonnaire. The findings revealed that average score of 77 of the respondents agree in terms of satisfaction and adoption of the application to be utilized in some institutions. The proposed application reduces the paper work of security officers and makes them more efficient.
Clinacanthus nutans, known to the locals as Belalai Gajah, is a medicinal plant widely used by Malaysians in the belief to cure various diseases including cancer. However, the production of Belalai Gajah hardly fulfils the market demand since the growing techniques of stem cutting and tissue culture are inefficient and expensive. Therefore, improvements in tissue culture techniques and materials application are required. Hence, this study tested Carica papaya (locally know as papaya) stem, an agricultural waste, to enhance the tissue culture of C. nutans. The effects of C. papaya stem powder and extract on the shoot proliferation of C. nutans parameters were investigated. The average number of shoot, leaves and length of leaves were observed. Phytochemicals screening was also conducted. Overall, C. papaya stem extract showed positive performance and 1% extract was found to be the optimum concentration to enhance the shoot proliferation. Meanwhile, C. papaya stem powder inhibited the shoot proliferation. It was also found that flavonoids, glycosides, steroid and terpenoid contributed in the shoot proliferation. In conclusion, the papaya stem extract is a potential in-vitro supplement for tissue culture studies. This study gained insights in sustainable green economy and showed that zero waste can be attained by converting local papaya stem waste to valuable product. In addition, sustainable technology in pharmaceutical approach could be addressed through in-vitro low cost large-scale production of Belalai Gajah medicinal plant.
An ideal model organism for neurotoxicology research should meet several characteristics, such as low cost and amenable for high throughput testing. Javanese medaka (JM) has been widely used in the ecotoxicological studies related to the marine and freshwater environment, but rarely utilized for biomedical research. Therefore, in this study, the applicability of using JM in the neurotoxicology research was assessed using biochemical comparison with an established model organism, the zebrafish. Identification of biochemical changes due to the neurotoxic effects of ethanol and endosulfan was assessed using Fourier Transform Infrared (FTIR) analysis. Treatment with ethanol affected the level of lipids, proteins, glycogens and nucleic acids in the brain of JM. Meanwhile, treatment with endosulfan showed alteration in the level of lipids and nucleic acids. For the zebrafish, exposure to ethanol affected the level of protein, fatty acid and amino acid, and exposure to endosulfan induced alteration in the fatty acids, amino acids, nucleic acids and protein in the brain of zebrafish. The sensitive response of the JM toward chemicals exposure proved that it was a valuable model for neurotoxicology research. More studies need to be conducted to further develop JM as an ideal model organism for neurotoxicology research.
Eshtehard aquifer located in southwest of Tehran province, Iran, provides a large amount of water requirement for inhabitants of Eshtehard district. Monitoring and analyzing of groundwater quality are important for protecting groundwater as sustainable water resource. One of the most advanced techniques for groundwater quality interpolation and mapping is geostatistics methods. The purposes of this study are (1) to investigate major ions concentration and their relative abundance to provide an overview of present groundwater chemistry and (2) to map the groundwater quality in the study area using geostatistics techniques. In this investigation, ArcGIS 9.2 was used for predicting spatial distribution of some groundwater characteristics such as: Chloride, Sulfate, pH, and Conductivity. These methods are applied for data from 44 wells within the study area. The final maps show that the south parts of the Eshtehard aquifer have suitable groundwater quality for human consumption and in general, the groundwater quality degrades south to north and west to east of the Eshtehard plain along the groundwater flow path.
Covalently cross-linked nanogels were prepared via irradiation of inverse micelles that had been preparedfrom radiation crosslinkable polymer, water, oil and surfactant. A mixture of polymer, water, heptane andsodium dioctyl sulfosuccinate (AOT) at certain compositions forms inverse micelles with the size rangingfrom 2 to 8 nm. The hydrophilic head of the surfactant facilitates encapsulation of water soluble polymer.If the entrapped polymer is radiation crosslinkable, it is expected that upon irradiation, polymerizationshall take place in such small and confined space, leading to formation of nano-sized polymeric gel.Meanwhile, emulsion at 2 nm size was chosen for gamma irradiation process. The formation of thenano-sized discreet gel using irradiation of inverse micelles technique was proven at a dose as low as 5kGy to obtain nanogel sized ~ 95 nm.
Bismuth oxide nanoparticles (Bi2O3 NPs) have gained a spot in the development of novel molecular
probes for in vivo biomedical imaging. It exists in six polymorphic forms and each of them exerts with
different stabilities according to its synthetisation temperature. The aim of this preliminary study is to
determine effect of different synthetiation temperatures on cellular viability in vitro. One hundred µg/ml
Bi2O3 NPs synthesised at 60, 90 and 120°C were characterised using scanning electron microscope (SEM)
and their cytotoxicity was evaluated using cell viability assay (MTT assay) upon 24 hours exposure to
Chang liver cells. Images captured by SEM showed an average diameter of 300 nm monoclinic-shaped
with high crystalline formation of all three Bi2O3 NPs. MTT assay revealed increase in liver cell viability
as the synthetisation temperature of Bi2O3 NPs increase. The outcomes suggested that synthetisation
temperature of Bi2O3 NPs plays a role in cellular viability, hence predictive to the biocompatibility of
these nanoparticles to be applied as in vivo radiographic contrast medium.
Heat exchangers are used in many industries and power generation applications. The performance of heat exchangers depends on the operating parameters and the types of flow. The sudden pressure drop is one of the major problems encountered in heat exchanger, and this would significantly affect the efficiency and the overall heat transfer coefficient of the heat exchanger. Therefore, this study is aimed at investigating and analyzing the effects of operating parameters that cause pressure fluctuation and affect the overall heat transfer coefficient. Experimental study was carried out for two types of flows: co-current and counter concurrent flows. Comparisons of the overall heat transfer coefficients between shell and tube and spiral coil heat exchangers were made. It was observed that mass flow rate affected the overall heat transfer coefficient. Besides, the counter current flow was more efficient compared to the co-current flow with enhanced overall heat transfer coefficient. The maximum overall heat transfer coefficient for spiral coil heat exchanger counter flow was 2702.78 W/m2.K, showing a higher heat transfer efficiency when compared to the shell and tube heat exchanger. Moreover, the spiral coil heat exchanger occupied less space as opposed to the shell and tube heat exchanger.
The increase of anthropogenic activities and growth of technology in Antarctica is fuelled by the high demand for petroleum hydrocarbons needed for daily activities. Oil and fuel spills that occur during explorations have caused hydrocarbon pollution in this region, prompting concern for the environment by polar communities and the larger world community. Crude oil and petroleum hydrocarbon products contain a wide variety of lethal components with high toxicity and low biodegradability. Hydrocarbon persistence in the Antarctic environment only worsens the issues stemming from environmental pollution as they can be long-term. Numerous efforts to lower the contamination level caused by these pollutants have been conducted mainly in bioremediation, an economical and degrading-wise method. Bioremediation mainly functions on conversion of complex toxic compounds to simpler organic compounds due to the consumption of hydrocarbons by microorganisms as their energy source. This review presents a summary of the collective understanding on bioremediation of petroleum hydrocarbons by microorganisms indigenous to the Antarctic region from past decades to current knowledge.
Oil spill introduces hydrocarbons into the marine environment and forms oil slicks, which aggregate with other debris to form tarballs. Tarballs are composed of toxic hydrocarbons, which persist in the environment, causing economic and ecological damages. This work studied the isolation and optimization of diesel-oil biodegradation by an indigenous bacterium, identified by 16S rRNA gene sequence analysis, in tarball. An experimental methodology using a Taguchi orthogonal array was applied to optimize the effects of diesel concentration, salinity, nitrate concentration, pH, temperature, agitation speed and time. An isolated bacterium identified as Cellulosimicrobium cellulans removed 88.4% of diesel oil under optimized conditions, where initial diesel-oil concentration was 5% (v/v), NaCl concentration was 20 gL-1 and NH4NO3 concentration was 2 gL-1 in Minimal Salt Media at pH 7, 40oC and 100 revolutions per minute for 5 days. Tarballs harbor hydrocarbon-degrading C. cellulans that can be used under optimized conditions to design an effective oil spill bioremediation technique for mitigating oil pollution.
The development of Transparent Solar Cells (TSC) has become the main focus of solar energy research in recent years. The TSC has a number of applications and make use of unexploited space such as skyscraper windows. In this paper, TSC is fabricated using commercially available titanium dioxide (TiO2) P25 to make a paste, which is deposited on FTO glass using screen printing and spin coating methods. The effects of the thickness of the TiO2 film on transparency are examined. The paste is synthesised in the Cleanroom and used in both methods of deposition. The final cell fabrication is a Dye sensitised solar cell (DSSC). The obtained transparency of the FTO glass is 83%, and after the deposition of TiO2 it is reduced to less than 80%. The overall transparency of the DSSC, which was made using the spin coating method, is 70% with an Isc of 9.5 mA and Voc 853mV.