The effects of the annealing temperatures and thicknesses on the shapes, sizes and arrangement of platinum (Pt) nanoparticles (NPs) on graphene and their sensing performance for hydrogen (H2) detection were investigated. It shows strong dependency of the annealing temperatures and thicknesses on the properties of NPs. It was found that the proposed technique is able to form the NPs with good size controllability and uniformity even for thick deposited layer, thus eliminating the requirement of very thin layer of below 5 nm for the direct NP synthesis by evaporation or sputtering. The transport properties of Pt NPs/graphene structure and its sensing performance on H2 at room temperature under various H2 concentration were evaluated. The results showed an acceptable sensing response, indicating an innovative approach to fabricate Pt NPs embedded graphene for gas sensing application.
A new contactless technique for latent fingerprint visualization on nonporous curved surfaces of circular cross section was introduced by Low et al. (1). The technique utilizes a plane mirror to convey the light rays toward the inspected surfaces for latent fingerprint visualization. This research activity came up as an extension of the previous study which utilized an aluminum plate as the plane mirror to illuminate the inspected surfaces. Dulling spray was used to increase the diffuse component of the reflective aluminum plate. However, the amount of dulling spray will affect the uniformity of the illumination on the inspected curved surfaces. In this study, a study on the new materials for the plane mirror was carried out. Coated aluminum, opal, and ground glass diffusers were selected as the new materials. The performance of the new materials was compared to the aluminum based on the quality of the captured images on various nonporous cylindrical surfaces. A statistical approach known as randomized complete block design was used to design the experiment. The quality of the captured images was obtained using Spectral Image Validation and Verification. Two-way analysis of variance and Fisher's least significant difference test were used to analyze the quality of the images. From the results of the statistical analysis, coated aluminum has the best performance compared to aluminum, opal, and ground glass diffusers.
A livelihood is a means of making a living, securing necessities of life such as water, shelter medicine and clothing. For communities dependent on forest resources for livelihoods, sustainability of forests are important. In Kampung Tambirat this study aims to find the income generated from forest resources particularly Nypah palm forests, the measures of conservation, challenges and type of assistance required so that the villagers engagement in the activities will flourish in the future and benefit the younger generations. It is found that there are no conservation measures for Nypah forests and seasonal floods further increases the difficulty for the villagers to sustain their livelihood activities.
The Silver Reed Model LK150 knitting machine is a home knitting machine which is
extremely lightweight and compact, making it preferable by most home knitters.
There are various knitwears with interesting patterns can be made using this model. In
the field of garments manufacturing by using flatbed knitting machines, it is
important to understand the physical properties of fabric so that their impact on
dimensional changes can be predicted to produce the most suitable end use. The
samples were produced by using a blended bamboo/cotton yarn, with a composition
of 30% cotton and 70% bamboo. The main objectives of this study are to to evaluate
the physical properties of single jersey fabric knitted on home knitting machine by
using different stitch dials and to relate the physical properties with different stitch
lengths. Then, all tests were conducted to compare the physical properties of samples
between three different stitch dials and the effects of before and after washing. The
physical properties measured in this research were stitch length, stitch density, weight,
thickness, absorbency and shrinkage. The result indicated that the longer the stitch
length, the higher the percentage of the water impact penetration. Meanwhile, there
was a slight reduction on the density, thickness and fabric weight. In addition, the
result after three times washing showed that the samples only had slight changes in
density, thickness, weight and stitch length, but has significant changes on the water
impact penetration.
Spatial and temporal variations in concentrations of several metals and isotopes in sediment cores from around Penang Island, an area with economically important biological resources off the northwest coast of peninsular Malaysia, are reported. Because of a typical, monazite rich mineralogy in surrounding drainage basins, sedimentary metal enrichment factors relative to global average materials, enrichment factors (EFs) of ˃1.0 do not always indicate significant anthropogenic metal inputs. Because of extensive metal solubilization in the hot, organic carbon rich area, EFs of < 1.0 may be observed for several metals despite significant anthropogenic contributions. Comparison of metal-Al relationships in Penang area surface sediments with those in nearby and presumed uncontaminated Strait of Malacca sediments more accurately correct for atypical regional solubilization and mineralogical effects than comparison to global average materials. Such comparisons show concentrations of Cd, Cu, Pb, Ni, Cr, As, Sb, Zn and V have changed by less than a factor of two by anthropogenic discharges. Sedimentary concentration profiles of Pb, Zn and Cu, ratioed to Sc to normalize for variations in grain size and mineralogy, have subsurface maxima suggestive of modest and recently reduced anthropogenic inputs. Mn, U, As and Sb have Sc-normalized concentration profiles clearly affected by diagenetic processes. Sc-normalized profiles of Cr, Th, Ce and Sm show only small changes with depth, confirming insignificant anthropogenic inputs and undetectable postdepositional diagenetic mobility.
Excess ²¹⁰Pb activities and fluxes in Penang area sediments are limited by supply of this radionuclide, in contrast to sediments of both the northwestern U.S.A. and Amazon continental shelves, where they are limited by particle scavenging reactions.²¹⁰Pb activities in sediments of
the shallow, dynamic Penang area often show erratic or unconvincing changes with depth that
cannot be reliably modeled by assuming steady state, constant deposition rate of particles of
uniform chemistry, mineralogy and initial unsupported ²¹⁰Pb, and that mixing is limited to a
recognizable surface layer and resemble a diffusive process.
The objective of this study was to evaluate the effects of milling methods on tensile properties of polypropylene (PP) / oil palm mesocarp fibre (OPMF) biocomposites. Two types of mills were used; Wiley mill (WM) and disc mill (DM). Ground OPMF from each milling process was examined for its particle size distribution and aspect ratio by sieve and microscopic analyses, respectively. Results showed that DM-OPMF had smaller diameter fibre with uniform particle size compared to the WM-OPMF. Surface morphology study by SEM showed that DM-OPMF had rougher surface compared to WM-OPMF. Furthermore, it was found that PP/DM-OPMF biocomposite had higher tensile strength compared to PP/WM-OPMF, with almost two-fold. Thus, it is suggested that small diameter and uniform size fibre may improve stress transfer and surface contact between the fibre and polymer matrix and cause well dispersion of filler throughout the polymer resulted in better tensile strength of PP/DM-OPMF Compared to PP/WM-OPMF biocomposite. Overall, it can be concluded that disc milling could serve as a simple and effective grinding method for improving the tensile properties of biocomposite.
A numerical simulation and analysis was performed to investigate the effect of absorber and buffer layer band gap grading and on a Copper-Indium-Gallium-Diselenide (CIGS) solar cell. The software used is the Solar Cell Capacitance Simulator (SCAPS). The absorber and buffer layer energy band structures’ effect on the cell’s output parameters such as open circuit voltage, short circuit current density, fill factor and efficiency were extensively simulated. Two structures of the energy band gap were simulated and studied for each of the absorber and buffer layer. The simulation was done on the uniform structure in which the energy band gap is constant throughout the layer. It was then continued on the cell with graded band structure, where the energy band gap of the material is varied throughout the layer. It was found that the cell with graded band structure in absorber and buffer layer had demonstrated higher efficiency and better performance in comparison with the cell with uniform band gap structure.
The medical education should be tailored to deal with the diseases the physician is most likely to see.' With expectations that all the graduates from Malaysian Medical Schools should be able to serve anywhere in the country, the need for a national curriculum is self-evident. It may be argued that the public must have confidence in the competence of the practitioners they depend upon irrespective of the school from which they had graduated. In smaller countries in which health needs are uniform the graduates of any school should have been trained to meet those needs. In larger countries and those with geographic diversities and distances (e.g. Malaysia), the curriculum should cover the commonly encountered diverse ailments. If not dealt with care, we may end up with huge load of ever expanding, unmanageable curriculum.
A comprehensive study on the spin-on-glass (SOG) based thin film insulating layer is presented. The SOG layer has been fabricated using simple MEMS technology which can play an important role as insulating layer of stack coupled microcoils. The fabrication process utilizes a simple, cost effective process technique as well as CMOS compatible resulting to a reproducible and good controlled process. It was observed that the spin speed and material preparation prior to the process affect to the thickness and surface quality of the layer. Through the annealing process at temperature 425oC in N2 atmospheric for 1 h, a 750 nm thin SOG layer with the surface roughness or the uniformity of about 1.5% can be achieved. Furthermore, the basic characteristics of the spiral coils, including the coupling characteristics and its parasitic capacitance were discussed in wide range of operating frequency. The results from this investigation showed a good prospect for the development of fully integrated planar magnetic field coupler and generator for sensing and actuating purposes.
Decomposition is degradation process of a corpse into basic respective constituents macroscopically and microscopically by action of microorganisms, arthropods and scavengers. Post mortem changes could be separated into early post mortem changes (i.e. algor mortis, rigor mortis and livor mortis) and putrefaction stages of corpse. These changes function as suitable indicators for determination of post mortem interval (PMI). In this paper, different stages of post mortem changes, possible variations such as mummification and formation of adipocere and special circumstances such as burial condition is discussed. This article also refers to several arguments in the different texture of adipocere and the influence of different types of fabric in affecting the post mortem changes and formation of adipocere. This is largely due to the property of permeability and resistance of material against degradation process. Undeniably, decomposition process involves numerous potential variables including burial condition, presence of clothing, potential formation of adipocere and mummification. Hence, studies in forensic taphonomy combined with real case scenario are crucial in understanding the nature of decomposition and estimation of PMI with higher accuracy.
Dry sliding wear of polyester hybrid composites containing carboxylic functionalized multi-walled carbon nanotubes (cNT) and microparticles, silica (Si02) was studied at different sliding distances. An attempt has been made to produce uniform dispersion of nano- and micro- particles in the test samples by ultrasonication. The tribological properties of the hybrid composites were performed by using pin-on-disc (POD) tester against grey cast iron countersurface. The dry sliding wear tests were carried out under pressure-velocity (pv) condition of 0.4 MPa and 4 m/s for total sliding distance of 28800 m and at an interval of every sliding distance of 3600 m, wear properties and behavior were studied. The samples containing 10 wt.% silica (microparticles) with and without CNT always show increase in coefficient of friction at the expense of wear rate. However, samples containing only ci'rr have the lowest wear rate with the increase in coefficient of friction. Sliding distance studies also provide the information on wear rates which were ever changing at different sliding distances whereas average coefficient of friction did not vary throughout the tests. SEM observations of wear surfaces showed different wear morphologies when reinforcement (cNT or Si02) incorporated into the composites either alone or in combination.
Work productivity is one of the most important economic measures in the manufacturing industry. However, the physical, psychosocial and individual risk factors of an industrial work environment affect workers' physical or mental health, resulting in work productivity loss, absenteeism and presenteeism. Therefore, this study aims to identify the most critical risk factors and develop statistical models for predicting work productivity loss, absenteeism and presenteeism of garment industry workers. A sample of 224 sewing machine operators was taken for data collection through observation and self-reported studies. The results indicated that the average work productivity loss, absenteeism and presenteeism was 38.21, 2.35 and 37.23%, respectively. Finally, the statistical models of work productivity loss, absenteeism and presenteeism was developed using multiple linear regression with precision of 69.9, 53.7 and 84.0%, respectively. Hence, this study will help garment industries to improve their work productivity by taking initiatives based on the developed models.
Accidental swallowing of objects commonly occurs among children and most of the objects pass through the gastrointestinal tract and out with the stool without any complications. However, recent reports have shown that there is an increasing occurrence of accidental ingestion of hijab pins among young hijab-wearing Muslim women or "hijabi". We highlight one such case, in which a young lady accidentally swallowed a pin that she was holding between her lips while she was styling her hijab. The pin was not successfully retrieved via endoscopy but was fortunately excreted spontaneously without any serious complications.
Unnecessary air conditioning for thermal comfort causeds energy over consumption. As air conditioning has become irreversible, one of the solutions is to run air conditioners at minimal energy without sacrificing the comfort of occupants in air conditioned space. The approach to thermal comfort is the key to successful thermal comfort research. Fanger's model has been adopted by ASHRAE and ISO standards but its universal applications have been debated. In recent decades, adaptive model that regards humans as adaptive beings has been accepted. The static and deterministic nature of Fanger's model has limited its application in hot, humid countries, such as Malaysia. This research aims to integrate the theories of Fanger and adaptive model into a new model which is applicable in Malaysia by taking the case in lecture halls. The new Fanger's Adaptive Model is established through normalization of the thermal sensation distribution obtained in thermal chamber by Fanger. The PMV range of 80% satisfaction has been widened to -1.3 to +1.3 which adopted the theories of adaptive model, where humans have the ability to adapt to environment. The research also includes field observations on Malaysian students clothing and activity levels in lecture halls. Previous field study results which proposed 25.3°C comfort temperature for lecture halls in Malaysia together with the field observation results were used to verify the new model. About 95% of PMV falls within the new range at this comfort temperature. It is proven that Fanger's model is semi-adaptive and probabilistic and the integration of Fanger's Adaptive Model is more accurate in predicting thermal comfort in hot and humid climate.
This exploratory study is part of an on-going project about digital cultures on ageism, anonymity, and gendering. An avatar is the graphical representation of the online user. The study investigates the avatars drawn by a group of 76 young adults studying in a local university. A face-to-face interview was conducted to ascertain the features drawn. Results show that the avatars are more characterized by the sexual features related to the body, face, clothes, and a major number of context elements. The females tend to represent themselves in greater detail than the males. The former created gendered identities for themselves according to their offline gender identity and social contexts. The study illustrates that the hand drawing is an effective tool that analyses the online representation in an unobtrusive way. The expressions of gendering show that gender is consciously constructed. Gendering of avatars does permeate the virtual world. This study is a valuable addition to the growing body of work on social interaction in cyberspace.
A Mondor’s disease is a rare, benign and self-limiting condition. It is due to thrombophlebitis of the superficial veins of the breast and chest wall. It usually occurs in middle-aged women who present with a palpable cordlike structure, often painful in the acute phase. The aetiology is unknown, and may be related to trauma, surgery, infection or tight clothing. The finding of a superficial vessel seen as a linear opacity on mammography and a tubular structure on ultrasound is typical. An intra-luminal thrombus may be seen on ultrasound, and there may be absent flow on Doppler imaging. Conservative treatment is usually instituted, although surgery may be indicated in certain circumstances.
Bananas were chilled at 6oC and the appearance of brown spots when exposed to ambient air, a
phenomenon known as chilling injury (CI), was detected using computer vision. The system consisted of a digital colour camera for acquiring images, an illumination set-up for uniform lighting, a computer for receiving, storing and displaying of images and software for analyzing the images. The RGB colour space values of the images were transformed into that of HSI colour space which is intuitive to human vision. Visual assessment of CI by means of a browning scale was used as a reference and correlation between this reference values and hue was investigated. Results of the computer vision study successfully demonstrate the potential of the system in substituting visual assessment in the evaluation of CI in bananas. The results indicate significant influence, at α=0.05, of treatment days and temperature on hue. A strong correlation was also found between hue and visual assessment with R>0.85.
Oil palm is widely grown in Malaysia. There has been interest in the utilization of oil palm biomass for production of environmental friendly biofuels. The gasification of empty fruit bunches (EFB), a waste of the palm oil industry, was investigated in this study to effectively and economically convert low value and highly distribution solid biomass to a uniform gaseous mixture mainly hydrogen (H2). The effects of temperature, equivalence ratio (ER) and catalyst adding on the yields and distribution of hydrogen rich gas products were also investigated. The main gas species generated, as identified by GC, were H2, CO, CO2, CH4 and trace amounts of C2H4 and C2H6. With temperature increasing from 700 to 1000 °C, the total gas yield was enhanced greatly and reached the maximum value (~ 90 wt. % ) at 1000°C with a big portion of H2 (38.02 vol. %) and CO (36.36 vol. %). Equivalence ratio (ER) showed a significant influence on the upgrading of hydrogen production and product distribution. The optimum ER (0.25) was found to attain a higher H2 yield (27.42 vol. %) at 850°C. The effect of adding catalysts (Malaysian dolomite1, P1), Malaysian dolomite2 (GML), NaOH, NaCl, CaO, ZnO, NiO) as a primary catalyst on gas product yield was investigated, and it was found that adding dolomite showed the greatest effect with the maximum H2 yield achieved (28.18 vol.%) at 850°C.
Ergonomics is generally to design for human use and optimizing the working and living conditions. The comfort, safety and ease of use of systems, products and machines require the principles of ergonomics to be incorporated into the design. Anthropometry is a part of ergonomics which deals with the measurement of body dimensions, its capability and limitations of the human ability. Studies have indicated that body dimensions differ for various populations, depending on ethnic group, sex and age. The measurement of physical characteristics and abilities of people provides information that is essential for the appropriate design of occupational and non- occupational environments, as well as for the design of consumer products, clothing, tools and equipment. It has been considered as the very basic core of ergonomics in an attempt to resolve the dilemma of 'fitting people to machines'. It has also been regarded as a branch of anthropology which deals with physical characteristics of the man in time and space, particularly with individual variation, ontogenesis and generic development. Knowledge about man from the point of view of physical anthropometry is very useful for the purpose of ergonomics and design. Thus it is important that an anthropometric database for each nation is developed to ensure design of products and systems are compatible with the user population. In Malaysia, many researchers have conducted anthropometric studies on various groups of people, focused on a small sample size and used for specific designs. Unfortunately, the measurements are not representatives of the population. The work has been individually based, confined to certain group of researchers in various universities and there is no concerted effort towards developing a national anthropometric database.This paper discusses some of the anthropometry work conducted in Malaysia, the problems and challenges in developing the national database, the importance of anthropometry and the roles that the government has to play in developing the database.