Mechanical responses and failure of fiber-reinforced polymer (FRP) composite
laminates could be predicted using the validated finite element (FE) simulation. The
material constitutive and damage models employed in the simulation are developed
based on the properties of the unidirectional lamina, including those obtained
through tension tests. Such computational model assumes perfectly aligned fibers in
the lamina. In this respect, this paper examined the effect of fabrication-inherited
fiber misalignment on the tensile response of the unidirectional lamina. For this
purpose, a series of tension tests are performed on unidirectional carbon fiberreinforced
polymer (CFRP) composite lamina specimens with different gage lengths
ranging from 50 to 150 mm. Fiber misalignment is quantified to be 7o and represents
the nominal deviation of the fibers from the reference longitudinal axis direction.
Load-displacement responses of the specimens are compared. Results show that the
nominal tensile strength of the lamina is 1089±33 MPa. The elastic modulus,
however, increases from 36.96 to 55.93 GPa as the gage lengths vary from 50 to 150
mm, respectively. This is due to the induced bending effects on the reinforcing fibers
that is greater for longer gage lengths. Multiple fiber fracture events, each is depicted
in a noticeable load drop, are recorded throughout the tensile loading of long lamina
specimens. Although the load at fracture is accurately reproduced by the FE
simulation using the damage-based mesoscale model, the effect of fiber
misalignment could not be captured.
Bioethanol is one of the leading alternative biofuel to fossil fuels and can be use in
existing gasoline engines without any major modification. Bioethanol can be
produced from sugar containing biomass fermentation using different potential
strains. In this study, the gram negative, facultative anaerobic, rod shaped strain
‘Zymomonas mobilis’ was used as microorganism to produce bioethanol from sugar
cane molasses using anaerobic fermentation. The study was conducted to investigate
the optimized conditions for production of bioethanol through batch fermentation
process. The fermentation unit was designed to determine the effect of process
parameters such as fermentation temperature, pH, sugar concentration and supply of
nutrients. The Zymomonas mobilis produced 9.3% (v/v) bioethanol by utilizing 16
g/100mL sugar with the fermentation efficiency 92.5%. The fertilized based nutrients
were supplied to enhance the production of bioethanol yield. The bioethanol yield
produced by using this strain in optimized conditions is in good compromise with
previous study and also compared with commercially available yeast strain.
Energy consumption of Wireless Sensor Networks (WSN) is an important aspect in
the design requirement. This is especially true in a situation where WSN is being
operated in isolated areas and thus relying on batteries due to unavailability of power
infrastructure. Since energy efficiency is the main concern in the deployment of WSN,
the sensor node must keep track of the charge that is left in the battery, commonly
referred as the State of Charge (SoC). To prevent the discontinuation of the operation
of the sensor node from power cut off, it is important to find an analytic model for
the battery’s state of charge. In this paper, an optimized structure of Multi-Layer
Perceptron (MLP) is utilized to obtain a model of the battery state-of-charge in
wireless sensor nodes. Results show the suitability of the method that produces
accurate and simple models, capable of being implemented even in low cost and very
constrained real motes.
Interest in Indigenous Knowledge (IK) system has been particularly highlighted in
flood disasters, due to the likely increase of flood events resulting from
anthropogenic climate change through heavy precipitation, increased catchment
wetness, and sea level rise. Therefore, bringing IK of flood risk reduction into focus
and context to deepen the understanding of how people manage their own changing
circumstances can bring more pertinent information about flood risk reduction. This
paper reviews the significance of IK in flood risk reduction. Specifically, the paper
discusses IK flood forecasting, early warning signs, adaptation and coping strategies
in flood risk reduction around the world. The Methodological approach employed for
this paper is the review of existing literature on IK in flood Disaster Risk Reduction
(DRR), and then a summary of the outcomes of the studies reviewed was discussed.
However, it was deduced from the review undertaken, the need for an intensive
empirical study to be conducted to explore how efficient these strategies or
techniques are, in relation to flood risk reduction, which this paper strongly
recommends for further investigation. Additionally, the paper concludes by
emphasizing that although the IK of flood risk reduction is embedded in varied
regions around the globe, still there is a need for further study to be carried out in
order to unveil why the similarities and variations in flood risk reduction
practices/strategies between regions.
In this study, we investigate the ability of the bacterial isolates from an Iraqi oil
reservoir, namely POS and PCO Oil to decolorize commercially used model azo dye Acid
Red-27(AR-27). The effects of inoculation volume and glycerol concentrations were
optimized to develop an economically feasible decolourization process. The isolates
were able to decolourize azo dye (AR27) at the highest decolorization efficiency of 98%
in 10 mL bacterial solution consisted of POS and PCO Oil and in the presence of 6.34
g/L glycerol. An optimized MFC using this bacterial consortium (POS + PCO Oil) and
graphite rod electrodes produced a maximum open circuit voltage (OCV) of 175 mV, in
the presence of potassium ferricyanide as the electron acceptor at the cathode. The
maximum current density of 1.7 μA/cm² and power density of 59.3 μW/cm² were
achieved when an external load of 5 kΩ was applied. Morphological analysis was
performed using Scanning Electron Microscope (SEM) to prove the bacterial
attachment onto the anode surface (graphite rod) in the MFC operation. This work
proposed that the bacterial strains POS and PCO Oil possess the ability to decolorize
Azo dye AR27 and generate electricity in the absence of nitrogen source.
A comfortable work space is important to produce productive work performance among workers. In Malaysia, the condition of office environment and its related issues on thermal comfort are fairly new. Past studies shown that the increment of energy consumption in high rise offices tend to increase dramatically. This is because the consumption of air condition for cooling accounts in office buildings had increased from 40% to 60% in recent years and the total electricity usage for office units also rises intensely due to urban heat island (UHI) resulted from modification of land surfaces. The objective of this paper therefore is to investigate the conditions and problems of existing prominent high rise office in Kuala Lumpur which is IBM Plaza and Menara Mesin Niaga in the scope of thermal comfort as well as describes an integrated passive design approach to reduce the cooling requirement for high-rise office building through an improved building envelope design using green technologies like external wall cladding following the GBI standard. This paper also attempts to get the user perception towards their existing workspace. For this purpose, case study as research strategy is adopted using mixed methodology combining qualitative and quantitative method under the framework of interpretivism and positivism research paradigm. Findings indicate that external wall cladding made of composite aluminium provides much advantages to the user. This study is important because appropriate design principles by adopting appropriate building envelope made of suitable material addressing ecology issues will not only provide a comfortable living environment to the users but also established referential guideline for future designers and scholars whom interested in office design.
Phytoremediation is considered as a cost-effective and environmentally friendly
technique for decontaminating environments that have been contaminated with
heavy metal ions. The technique describes the use of plants and their concomitant
microbes to mitigate environmental contaminations. However, conventional
remediation techniques like chemical, thermal and physical treatment methods are
too costly, and may end of causing more contamination to the environment.
Phytoremediation practice provides a major information on the utilization of plants
and their materials in decontaminating polluted environments. Heavy metals and
other organic contaminants are among the most precarious substances released into
the environment which have an eminent level of toxicity and sturdiness of both
aquatic and terrestrial organisms. The review aimed at providing a broad
understanding of utilizing various plants and their materials in decontaminating
polluted environments with heavy metals and other organic contaminants. It also
provided the general methods used in treating the aforementioned contaminants in
an environment. The review further discussed the classes of phytoremediation like
phytoextraction, phytovolatilisation, phytostabilization, phytotransformation,
phytodegradation and phytofiltration. The generalized advantages and disadvantages
of phytoremediation were ultimately highlighted.