OBJECTIVE: The unavailability of anthropometric data especially in developing countries has remained a limiting factor towards the design of learning facilities with sufficient ergonomic consideration. Attempts to use anthropometric data from developed countries have led to provision of school facilities unfit for the users. The purpose of this paper is to use factor analysis to investigate the suitability of the collected anthropometric data as a database for school design in Nigerian tertiary institutions.
PARTICIPANTS: Anthropometric data were collected from 288 male students in a Federal Polytechnic in North-West of Nigeria. Their age is between 18-25 years.
METHODS: Nine vertical anthropometric dimensions related to heights were collected using the conventional traditional equipment. Exploratory factor analysis was used to categorize the variables into a model consisting of two factors. Thereafter, confirmatory factor analysis was used to investigate the fit of the data to the proposed model.
RESULTS: A just identified model, made of two factors, each with three variables was developed. The variables within the model accounted for 81% of the total variation of the entire data. The model was found to demonstrate adequate validity and reliability. Various measuring indices were used to verify that the model fits the data properly. The final model reveals that stature height and eye height sitting were the most stable variables for designs that have to do with standing and sitting construct.
CONCLUSION: The study has shown the application of factor analysis in anthropometric data analysis. The study highlighted the relevance of these statistical tools to investigate variability among anthropometric data involving diverse population, which has not been widely used for analyzing previous anthropometric data. The collected data is therefore suitable for use while designing for Nigerian students.
KEYWORDS: Exploratory factor analysis; measurement model; school ergonomics
Exposure to PCDD/PCDF (dioxin and furan) through consumption of fish and shellfish is closely related to the occurrence of skin diseases, such as chloracne and hyperpigmentation. This study aimed to determine the exposure of PCDD/PCDF and its congeners in fish and shellfish obtained from different regions of the Straits of Malacca among the fishing community.
Free-piston engine generators (FPEGs) have huge potential to be the principal energy conversion device for generating electricity from fuel as part of a hybrid-electric vehicle (EV) powertrain system. The principal advantages lay in the fact that they are theoretically more efficient, more compact, and more lightweight compared to other competing EV hybrid and range-extender solutions (internal combustion engines, rotary engines, fuel cells, etc.). However, this potential has yet to be realized. This article details a novel dual-piston FPEG configuration and presents the full layout of a system and provides technical evidence of a commercial FPEG system's likely size and weight. The work also presents the first results obtained from a project which set-out to realize an operational FPEG system in hardware through the development and testing of a flexible prototype test platform. The work presents the performance and control system characteristics, for a first of a kind system; these show great technical potential with stable and repeatable combustion events achieved with around 700 W per cylinder and 26% indicated efficiency.
The combustion characteristics of refuse derived fuel (RDF) in a fluidized bed have been studied. The gross heating value (GHv) of the RDF was 14.43 MJIkg with moisture content of 25% by weight. Parameters of interest for sustainable bed combustion were the fluidization number and primary air factor. The study was performed in a rectangular fluidized bed combustor with dimensions of 0.3 m in width, 0.7 m in length and 2 m in height. Sand with mean particle size of 0.34 mm was used as a fluidization medium. The sand bed height was at 0.3 m above the standpipes air distributor. The range of fluidization number under investigation was 5-7 II fin which 5 II newas found to be the optimum. The study was continued for the determination of the optimum primary air factor with the selected range of primary air factors being 0.6, 0.8, 1.0 and 12 in experiments conducted at 5 Unit The final results showed that the optimum primary air factor was at 0.8. An energy balance was also performed to determine the thermal efficiency of the combustion. It was concluded that the thermal efficiency depended on the bed temperature and the primary air factor being used.
To assess the effect of dietary ascorbate on lipid metabolism, 1-year black sea bream (Acanthopagrus schlegelii) were reared on a casein-based purified diet and an ascorbate fortified diet (1,100 mg of L: -ascorbyl-2- monophosphate-Mg/kg diet). The fortified ascorbate was effectively incorporated into the fish body and elevated muscle carnitine content. Fortifications of dietary ascorbate depressed activities of glucose-6-phosphate dehydrogenase and NADP-isocitrate dehydrogenase as lipogenic enzymes in the hepatopancreas and intraperitoneal fat body. Starvation after feeding experiment activated carnitine palmitoyltransferase as a lipolysis enzyme in the hepatopancreas in both control and vitamin C(VC) groups, while the lipolysis activity was significantly higher in VC group. These results confirmed that dietary ascorbate depressed lipogenesis and activated lipolysis, i.e., influenced the lipid metabolism of black sea bream.
This paper presents an anthropometric database of high school and university students from Kuala Lumpur, Malaysia. Forty-one high school participants (21 males and 20 females), 13-17 years old, and 143 university students (74 males and 69 females) took part in the study. Twenty-one static body dimensions were measured. The greatest mean differences in the anthropometric data between male and female high school students were found in the sitting elbow height. In addition, a comparison of anthropometric data of male and female university students showed that data for males and females were significantly different, except for buttock-popliteal length, sitting elbow height and thigh clearance. The primary aim of this study was to develop an anthropometric database that could be used as a primary reference in designing products, devices and equipment for ergonomic learning environments.
BACKGROUND: This study was to investigate the prevalence of single nucleotide polymorphisms (SNPs) in leptin gene LEP (A19G and G2548A) and leptin receptor gene LEPR (K109R and Q223R) and their association with fasting plasma leptin level (PLL) and obesity in a Malaysian suburban population in Kampar, Perak.
METHODS: Convenience sampling was performed with informed consents, and the study sample was drawn from patients who were patrons of the Kampar Health Clinic. A total of 408 subjects (mean age, 52.4 +/- 13.7 years; 169 men, 239 women; 190 obese, 218 non-obese; 148 Malays, 177 ethnic Chinese, 83 ethnic Indians) participated. Socio-demographic data and anthropometric measurements were taken, and genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).
RESULTS: The LEP A19G, G2548A and LEPR K109R, Q223R variant allele frequencies were 0.74, 0.67 and 0.61, 0.79, respectively. The genotype and allele distributions of these gene variants were significantly different among ethnic groups, but not among body mass index (BMI) classes. Subjects with LEPR K109 and Q223 allele had significantly higher systolic blood pressure and adiposity indices after adjustment for ethnicity (higher BMI, total body and subcutaneous fat; lower skeletal muscle percentage). Subjects with LEPR 109R allele had lower PLL than their wild-type allele counterparts. The influence of LEP A19G and G2548A SNPs on blood pressures, anthropometrics, and PLL was not evident. Interestingly, synergistic effect of the LEP and LEPR SNPs was observed as subjects homozygous for all four SNPs studied exhibited significantly higher subcutaneous fat and PLL than those with other genotype combinations.
CONCLUSIONS: The LEP and LEPR SNPs in this study may not be an obesity marker among Malaysians in this population, but were associated with ethnicity. Our findings suggest that each of these SNPs contributes to minor but significant variation in obesity-related traits and in combination they display synergistic effects on subcutaneous fat and PLL.
In a meristic, morphometric and distributional study of Neolissochilus from Peninsular Malaysia, Khaironizam et al. (2015) subsumed Lissochilus tweediei Herre in Herre & Myers 1937 and a taxon they called "Tor soro Bishop 1973" into the synonymy of N. soroides (Duncker 1904) based on data collected from museum specimens. However, "Bishop 1973" is not the correct author citation for Tor soro. Instead, Tor (now placed in Neolissochilus) soro was originally described as Barbus soro by Valenciennes in Cuvier & Valenciennes (1842:191). Since "Tor soro Bishop 1973" is not a valid name/author combination, Neolissochilus soro, as treated by Khaironizam et al. (2015), cannot be considered a junior synonym of N. soroides.
Granulation is an important step during the production of urea granules. Most of the commercial binders used for granulation are toxic and non-biodegradable. In this study, a fully biodegradable and cost-effective starch-based binder is used for urea granulation in a fluidized bed granulator. The effect of binder properties such as viscosity, surface tension, contact angle, penetration time, and liquid bridge bonding force on granulation performance is studied. In addition, the effect of fluidized bed process parameters such as fluidizing air inlet velocity, air temperature, weight of primary urea particles, binder spray rate, and binder concentration is also evaluated using response surface methodology. Based on the results, binder with higher concentration demonstrates higher viscosity and higher penetration time that potentially enhance the granulation performance. The viscous Stokes number for binder with higher concentration is lower than critical Stokes number that increases coalescence rate. Higher viscosity and lower restitution coefficient of urea particles result in elastic losses and subsequent successful coalescence. Statistical analysis indicate that air velocity, air temperature, and weight of primary urea particles have major effects on granulation performance. Higher air velocity increases probability of collision, whereby lower temperature prevents binder to be dried up prior to collision. Findings of this study can be useful for process scale-up and industrial application.
It has been observed previously that the physical behaviors of Schmidt number (Sc) and Prandtl number (Pr) of an energy-conserving dissipative particle dynamics (eDPD) fluid can be reproduced by the temperature-dependent weight function appearing in the dissipative force term. In this paper, we proposed a simple and systematic method to develop the temperature-dependent weight function in order to better reproduce the physical fluid properties. The method was then used to study a variety of phase-change problems involving solidification. The concept of the "mushy" eDPD particle was introduced in order to better capture the temperature profile in the vicinity of the solid-liquid interface, particularly for the case involving high thermal conductivity ratio. Meanwhile, a way to implement the constant temperature boundary condition at the wall was presented. The numerical solutions of one- and two-dimensional solidification problems were then compared with the analytical solutions and/or experimental results and the agreements were promising.
This study investigated the dry and aqueous erosion of mild steel using electrochemical and dry sand impact techniques. In dry sand impact experiments, mild steel was eroded with 45 μm and 150 μm sand particles. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and micro-hardness techniques were used to elaborate the surface morphology of the eroded samples. The results revealed significant change in morphology of the eroded samples. In-depth analysis showed that although the metal erosion due to larger particles was significantly higher, the fines also notably damaged the metal surface. The surface damages were appreciably reduced with decrease in impact angle of the accelerated particles. The maximum damages were observed at an impact angle of 90°. The hardness of the samples treated with 45 μm and 150 μm sand remained in the range of 88.34 to 102.31 VHN and 87.7 to 97.55 VHN, respectively. In electrochemical experiments, a triple electrode probe was added into the metal treatment process. The linear polarization resistance (LPR) measurements were performed in slurries having 5% (by weight) of sand particles. LPR of the samples treated with 45 μm and 150 μm sand slurries was calculated about 949 Ω.cm(2) and 809 Ω.cm(2), respectively.
Mini purse seine has a major contribution in increasing production of small pelagic catches in Pelabuhan Perikanan Pantai (PPP) Muncar. This research aimed to investigate the effectiveness and efficiency of mini one-boat and two-boat purse seine in Bali Strait, Indonesia. This research was conducted in Mei 2018 in Muncar, East Java, Indonesia. In this study, survey was used to get the data by distributed the questioners to the fisherman. The primary data are total catch composition, fork length, individual weight of total catch and operation time of both fishing gears. Data were analysed by main catch and bycatch proportion, legal size proportion and catch rate. The results showed that the mini two-boat purse seine had a greater catch volume compared to the mini one-boat purse seine. The bycatch composition dominates in both fishing gear. The proportion of legal-size catching is 67% of the total. The fork length is not significantly different and for the total catches is significantly different. The catching rate of the mini purse seine one boat catch rate is lower at 4,048.67 kg/hour, compared to the mini two-boat purse seine which is 9,189.18 kg/hour.
Double-burden of malnutrition (DBM) is an emerging public health concern among the Orang Asli (indigenous peoples) of Peninsular Malaysia. This study aimed to identify the presence of DBM at the community and household levels in Orang Asli population and its associated demographic and socio-economic factors.
Sludge is an unavoidable product of wastewater treatment that creates problems of disposal. Increasingly, strict environmental control regulations have resulted in limitations on sludge disposal options.Disposal by incineration has been found to be a good option. In this research, application of domestic waste sludge powder (DWSP) was used as cement replacement in concrete mix. This study utilised replacement of 3 %, 5 %, 7 %, 10 % and 15 % by weight of OPC with water binder (w/b) ratio of 0.60, 0.55 and 0.40 for Grade 30, Grade 40 and Grade 50 respectively. The performance of DWSP concrete in terms of its compressive strength, water absorption, water permeability and Rapid Chloride Ion penetration were investigated. All values of compressive strength for DWSP concrete were lower compared to the OPC control, and the strength decreased as the percentage of replacement with DWSP increased for Grade 30 and Grade 50, except for Grade 40 at replacement of 7 %. Meanwhile, water absorption and water permeability for the DWSP concrete increased as the replacement increased. Overall, with further research in producing quality DWSP, the potential of using this waste as a cement replacement material is very promising.
We examined the geographical variation of the skull size and shape of the lesser mouse deer (Tragulus javanicus) from Laos, Thailand, Peninsular Malaysia, Sumatra, Java, Borneo, Langkawi and some Islands of Tenasserim in Myanmar. Although the influence of the climatic condition on skull size was not confirmed in the mainland populations, the skull became rostro-caudally longer in the populations of Tenasserim and Sumatra because of island isolation effect. The skull size was classified into the following three clusters of localities from the matrix of Q-mode correlation coefficients: 1) Langkawi and Tenasserim, 2) Laos and Thailand, 3) Sumatra and Borneo. The skulls in the population of Java belong to the cluster of Langkawi and Tenasserim in male, however were morphologically similar to those in the cluster of Borneo and Sumatra. The canonical discriminant analysis pointed out that the Laos and Tenasserim populations were separated from the other ones and that the populations of Sumatra, Java and Borneo were intermingled each other.
Two forms of Staurois that are differentiated by body size occur parapatrically in the Crocker Range, Sabah, Borneo. Analyses of a total of 1,499 bp of the mitochondrial cytochrome b, 12S rRNA, and 16S rRNA genes revealed that the two forms could be completely split genetically. The two forms could be also clearly differentiated morphologically, not only by snout-vent length but also by the relative sizes of snout, eye, and finger disk. Comparisons of the two forms with all known species of the genus revealed the large and small forms to be S. tuberilinguis and S. parvus, respectively. The latter species has long been synonymized with the former, but we here consider them to represent different species.
Composite archery bows have been well known and used by Asiatic societies for thousands of years. The Turkish composite bow, made of wood, horn, sinew and glue is one of the most famous and powerful bows in the world. Because of its high draw weight and mechanical efficiency, the Turkish composite bow became a powerful weapon in the Seljuk and the Ottoman empire. In addition to being a powerful weapon of war, at the same time the bow and arrow (archery) continued
to be a sport of Ottoman (sultans, state officials, janissaries) until the late Ottoman period. In this study of the Ottoman composite archery bows in the collections of Izmir Ethnography Museum, a small wood sample was investigated on the basis of its wood anatomy. The results showed that it was made of maple wood (Acer sp.) and some of its qualitative and quantitative anatomical properties are presented here. One of the key properties for the identification of maple wood is
the helical thickening throughout the body of the vessel element. Helical thickenings in vessel elements in cutting surfaces of maple-wooden core increase the bonding surface between the wood and sinew-horn. In most of the woods preferred traditionally for bow-making, helical thickenings in tracheids, vessel elements or ground tissue fibres should be taken into account at a hierarchy of cellular structures for elucidating the efficiency of Ottoman composite-wooden bow.
The alkali-silica reaction (ASR) is an important consideration in ensuring the long-term durability of concrete materials, especially for those containing reactive aggregates. Although fly ash (FA) has proven to be useful in preventing ASR expansion, the filler effect and the effect of FA fineness on ASR expansion are not well defined in the present literature. Hence, this study aimed to examine the effects of the filler and fineness of FA on ASR mortar expansion. FAs with two different finenesses were used to substitute ordinary Portland cement (OPC) at 20% by weight of binder. River sand (RS) with the same fineness as the FA was also used to replace OPC at the same rate as FA. The replacement of OPC with RS (an inert material) was carried out to observe the filler effect of FA on ASR. The results showed that FA and RS provided lower ASR expansions compared with the control mortar. Fine and coarse fly ashes in this study had almost the same effectiveness in mitigating the ASR expansion of the mortars. For the filler effect, smaller particles of RS had more influence on the ASR reduction than RS with coarser particles. A significant mitigation of the ASR expansion was obtained by decreasing the OPC content in the mortar mixture through its partial substitution with FA and RS.
This paper is about the reduction of the overall size of metal blanking sheet that is being used to form a stamping product or car body panel of a car manufacturer in Malaysia. The current blanking sheet produces extra waste which will be recycled and does not contribute to increase productivity but increases inventory cost. The reduction in the blanking sheet size will lead to the reduction of raw material hence reduced the production cost. However, the reduced size of blanking sheet could affect the yield strength of the product. The study of the yield strength and yield improvement of the product are done by simulating stress analysis by using CATIA software. The results show that the new proposed size of the metal blanking sheet provides accuracy of the product dimension as well as maintaining the yield strength of the product and it reduced a significant amount of metal scrap which is nearly 4% of material weight and save around 10% of inventory cost.
Paper recycling plants usually buy their raw material from suppliers. More than often, bulk used paper supplied to the plant contains some significant quantity of water in its internal voids. It may be included intentionally or unintentionally. The price of used paper depends on its weight, thus adding water will help to increase weight and consequently increase the price. In this way, plant owner who purchase the used paper suffers a significant of financial lost. The objectives of our experiment are to establish a calibration curve that correlate between the amount of neutron backscattered and water content, and finally to develop a correction factor that need to be introduced to the measured values of water content. A fast neutron source (Am-Be 241) and a portable backscattering neutron detector were used for water measurement. The experiments were carried out by measuring neutron backscattering from used paper that has been added with different amount of water. As a result, a neutron calibration curve that provides a correlation between neutron backscattering and water content was established.