In this work, 10 mol% yttrium-doped ceria powders, Ce0.9Y0.1O1.95, were synthesised using a new mechanical technique, mechanochemical reaction, in which both impact action and shearing forces were applied for efficient fine grinding, subsequently leading to higher homogeneity of the resultant powders. Ce0.9Y0.1O1.95 prepared using this new technique was systematically compared with a sample of the same prepared using conventional solid-state methodology. X-ray diffraction analysis showed all prepared samples were single phase with a cubic fluorite structure. Generally, Y2O3-doped CeO2 electrolytes prepared by mechanochemical reactions were stable at a lower temperature (1100 °C) compared with a sample of the same synthesised using the conventional solid-state method. Characterisations using differential thermal analysis (DTA) and thermogravimetric analysis (TGA) showed no thermal changes and phase transitions, indicating all materials were thermally stable. The electrical properties of the samples investigated by AC impedance spectroscopy in the temperature range 200–800 ˚C are presented and discussed. Scanning electron microscopy (SEM) was used to study the morphology of the materials. Fine-grained powders with uniform grain-size distribution were obtained from the mechanochemical reaction.
Tropical greenhouses require active evaporative cooling system such as pad-and-fan to ensure a suitable microclimate for crop production. Excess heat causes indoor temperature to become hotter than desired resulting in detrimental effects to crop growth and production. Solar radiation intensity and outside temperature affect temperature and relative humidity level inside a greenhouse, while wide gradients in temperature and relative humidity can cause problems related to crop growth and production uniformity. A 300 m2 greenhouse, equipped with evaporative pad and four exhaust fans at each end walls, was used in the study. Horizontal and vertical profiles of the temperature and relative humidity inside the greenhouse were investigated. Results showed that temperature increased from evaporative pad area to exhaust fans area in a horizontal plane, while relative humidity showed an inverse pattern from temperature. In the vertical plane, temperature increased, while relative humidity decreased from lower level to the upper level. ANOVA results showed that in overall, temperature and relative humidity inside the greenhouse were uniform as there was no significant difference at 95% confidence interval. Thus, it was concluded that greenhouse cooling system by evaporative pad and exhaust fans are suitable for application in a tropical country such as Malaysia.
Land development, especially construction works, increase storm water volumes and pollution loads into rivers and lakes. The temporary drainage system at construction sites, particularly during the construction stage discharges a large amount of pollutants that can damage the aquatic system of the receiving water bodies. The potential of vegetative swale to alleviate this problem was evaluated. The size of the constructed vegetative swale was 7cm deep, 400cm long and 15cm wide at the bottom, and 17cm wide at the top. The experiment was conducted batch wise by filling the storage tank with the run-off water from the construction site. The water was allowed to flow through a pipe into the retention basin to maintain uniform flow before it entered the swale. The study showed that the run-off infiltrated through the soil at a rate of 489.6 mm/hr. Samples of surface run-off and infiltration water were collected at the end and the bottom of the swale. The results indicate that chemical oxygen demand (COD), total suspended solid (TSS), turbidity, iron and zinc were reduced by 85.4%, 80.8%, 36.4%, 52.8% and 96.0%, respectively, by surface flow and 91.1%, 98.8%, 58.2% 55.5% and 98.1%, respectively, by infiltration. Removal of nitrate and phosphorus by the planted vegetation was 69.4% and 21.1%, respectively, by infiltration. However, nutrient removal by surface flow was negligible. In conclusion, the vegetative swale was able to improve the water quality of the storm water run-off from the construction site from Class V to Class III, according to the Interim National Water Quality Standards for Malaysia.
A 30-year-old Iban woman presented to a rural primary healthcare clinic located along the Batang Rejang in Sarawak. She had a 2-day history of rash, which started over her trunk and later spread to her face and limbs. What started out as individual erythematous maculopapular spots later coalesced to form larger raised blotches. The rash was extremely pruritic and affected her sleep, and hence her visit. The rash was preceded by high grade, persistent fever that was temporarily relieved by paracetamol. She also complained of malaise, arthralgia and myalgia. Her appetite had been poor since the onset of the fever. She lived in a long house at the edge of the jungle. Although she did not have a history of going into the jungle to forage, she went regularly to the river to wash clothes. Clinically, she appeared lethargic and had bilateral conjunctival injection. Her left anterior cervical lymph nodes were palpable. There were erythematous macules measuring 5 to 15 mm distributed over her whole body but predominantly over the chest and abdominal region (Figure 1). An unusual skin lesion was discovered at the right hypochondriac region. This lesion resembled a cigarette burn with a necrotic centre (Figure 2). There was no evidence of hepato-splenomegaly. Examination of the other systems was unremarkable. On further questioning, the patient admitted being bitten by a ‘kutu babi’ or mite 3 days before the onset of her fever.
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.
Accident in an organization is one of the most undesirable phenomenons all over the world. The consequences of accidents in workplace are numerous which include damages of resources and cost of lives of many workers. For example, in 1991 a major disaster occurred in U.S. at triangle Shirtwaist factory, which cost the life of 100 garments workers (Greenwald & Richard, 2005). In Bangladesh accidents in workplace are more frequent and devastating, for which Bangladesh has been criticized severely worldwide. Recently one of those unfortunate phenomenons in Bangladesh was fire at Nimtoli of old Dhaka which cost 117 people burnt alive in June 2010. Another accident took place in Tazreen Fashion, Dhaka in 2012 which caused at least 112 workers either burnt to death or died while trying to escape the blaze. These are the short picture of loss of lives. Yet the losses of resources are not few. Sometimes accidents create threats for human and animal kingdom also by large rate of environmental pollution. For Example, in 2005 devastating Texas City Refinery explosion cost lives of many workers as well as light hydrocarbons concentrated at ground level throughout a large surrounding area which caused long lasting environmental pollution (Baldwin & Lisa, 2008). Furthermore, economic loss cannot also be over looked. A little mistake costs huge loss in assembly line of work. Thus accidents reduce production rate, lessen the quality of product and the reputation of industry also.
The paper is aimed at studying fluid flow heat transfer in the axisymmetric boundary layer flow of a viscous incompressible fluid, along the axial direction of a vertical stationary isothermal cylinder in presence of uniform free stream with momentum slip. The equations governing the flow i.e. continuity, momentum and energy equation are transformed into non-similar boundary layer equations and are solved numerically employing asymptotic series method with Shanks transformation. The numerical scheme involves the Runge-Kutta fourth order scheme along with the shooting technique. The flow is analyzed for both assisting and opposing buoyancy and the effect of different parameters on fluid velocity, temperature distribution, heat transfer and shear stress parameters is presented graphically.
Polarization in antiferroelectric liquid crystals has two origins: The piezoelectric polarization which is of chiral origin and the flexoelectric polarization which originates in different orientation of tilts in neighboring layers. The flexoelectric polarization is perpendicular to the tilt direction only if the structure is uniformly helicoidally modulated. In structures like SmC*F11andSmC;12 the flexoelectric contribution might be significant and it can be non-parallel to the piezoelectric component. Hence it may deviates the direction of polarization from the perpendicular direction significantly. The angle formed by the polarization and the tilt is therefore general and as such the basic characteristic of the SmCG* phase can be recognized. It seems that this aspect was completely overlooked in the past. In this contribution we analyze the dependence of the polarization direction on the phase structures and on the values of piezoelectric and flexoelectric coefficients in the discrete phenomenological model.
Post mortem changes are important in estimating post mortem interval (PMI). This project's aim was to study the effect of burial and type of clothing on rate of decomposition, which can contribute to estimating PMI for victims. 12 rabbits (Oryctolagus cuniculus) carcasses were separated into 3 groups: no clothing, light clothing and heavy clothing. Control subjects were placed on the ground surface while test subjects were buried at 30 cm depth graves. Soil samples prior and after decomposition were collected for soil pH and moisture analysis. Post mortem change was assessed using a Total Body Score system. The head, neck and limb regions were found to decay faster than the body trunk region. Mummifi cation occurred on body parts that were exposed directly to the atmosphere while adipocere formed on some buried subjects. Burial delayed decomposition due to lower insect activity and lower soil temperature. The soil layer also blocked the accessibility of majority of the arthropods, causing further delay in decomposition. Clothing enhanced decay for bodies on ground surface because it provided protection for maggots and retained moisture on tissues. However, clothing delayed decomposition in buried bodies because it physically separated the bodies from soil and arthropods. Higher sun exposure and repetitive exhumation showed acceleration of decomposition. The decomposition process increased soil pH and moisture percentage values. Soil pH initially increased until pH 8.0-8.4 followed by a slight decrease while soil moisture percentage changed inconsistently. Burial was significant in affecting post mortem change, F(1,11)=12.991, p<0.05 while type of clothing was not significant, F(2,9)=0.022, p=0.978 and combination of both type of clothing and burial factors were also not significant, F(2,3)=0.429, p=0.686. For validation, an accuracy of 83.33% was achieved based on soil pH and soil moisture percentage analysis.
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.
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.
A high-order uniform Cartesian grid compact finite difference scheme for the Goursat problem is developed. The basic idea of high-order compact schemes is to find the compact approximations to the derivatives terms by differentiating centrally the governing equations. Our compact scheme will approximate the derivative terms by involving the higher terms and reducing the number of grid points. The compact finite difference scheme is given for general form of the Goursat problem in uniform domain and illustrates the performance by applying a linear problem. Numerical experiments have been conducted with the new scheme and encouraging results have been obtained. In this paper we present the compact finite difference scheme for the Goursat problem. With the aid of computational software the scheme was programmed for determining the relative errors of linear Goursat problem.
Diarrhea is a common complication in patients receiving enteral nutrition (EN), and understanding this problem among patients and healthcare professionals is required. The aim of the study was to investigate patients', nurses', and dietitians' definitions of diarrhea during EN, the attitudes of nurses and patients toward it, and the management practices of nurses and dietitians in response to diarrhea during EN.
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.
It is well known that the endocrine-disrupting chemical (EDC) dibutylphthalate (DBP) inhibits testosterone synthesis and can lead to feminisation in male laboratory animals. Moreover, it has long been speculated that human exposure would result in the similar effects, but this is difficult to study because specific human exposure cohorts are rare. We report increases in the incidences of hypospadias (p<0.05), cryptorchidism (p<0.05) and breast cancer (p<0.05) in the children of New Zealand soldiers who served in Malaya (1948-1960) and were exposed to DBP applied daily to their clothing as an acaricide to prevent tick-transmitted bush typhus. In addition, we modelled absorption of DBP from the soldiers' clothing and using published data for skin absorption, and calculated a large theoretical absorbed dose of 64 mg/kg body weight/day which is similar to DBP's lowest observed adverse effect level (LOAEL) of 50 mg/kg body weight/day and thus indicates a biological effect is possible. This is the first report of a multigenerational developmental effect following DBP exposure in human males.
Vitamin D status is influenced by sun exposure, geographic latitude, daily outdoor activities, body surface exposed to sunlight and dietary intakes. Malaysia, is sunny all year round. However, the vitamin D status of this population especially among the healthy and free living adults is not known. Therefore a study of vitamin D status and associated factors was initiated among an existing Malay cohort in Kuala Lumpur. A total of 380 subjects were sampled to have their vitamin D status assessed using 25-hydroxyvitamin D (25(OH)D). A short questionnaire enquiring socio-demographic characteristics, exposure to sunlight and clothing style was administered. Their mean age was 48.5±5.2years and the mean 25(OH)D for males and females were 56.2±18.9nmol/L and 36.2±13.4nmol/L respectively. There were significant positive correlation for sun exposure score (r=0.27, p<0.001) and negative correlation for sun protection score (r=-0.41, p<0.001) with 25(OH)D levels. In the logistic regression model, females (OR=2.93; 95% CI: 1.17, 7.31), BMI (1.1; 1.03, 1.20) and sun exposure score (0.998; 0.996, 0.999) were significantly associated with vitamin D status as represented by 25(OH)D levels. Our findings show that obesity, lifestyle behaviours and clothing style are directly associated with our participants especially females' low vitamin D status.
Gait stability is primary in assessing individuals with high risk of falling, particularly the elderly. Custom made self-adjustable wireless gyroscope suit is used as a sensing device to quantify gait stability. A nonlinear time series analysis i.e. maximum Lyapunov exponent (λ*) was employed to estimate the short term and long term stability and it is closely related to the ability of human neuro-muscular control system in maintaining gait stability. Experimental analysis and tests validated the efficacy of this novel approach. The results achieved are comparable with the findings of multiple kinematic and dynamic parameters derived from optical motion capture system and force platform which are widely used as gold standard.