Abstract: Two finite element (FEM) models are presented in
this paper to address the random nature of the response of glued
timber structures made of wood segments with variable elastic
moduli evaluated from 3600 indentation measurements. This total
database served to create the same number of ensembles as was the
number of segments in the tested beam. Statistics of these ensembles
were then assigned to given segments of beams and the Latin
Hypercube Sampling (LHS) method was called to perform 100
simulations resulting into the ensemble of 100 deflections subjected
to statistical evaluation. Here, a detailed geometrical arrangement of
individual segments in the laminated beam was considered in the
construction of two-dimensional FEM model subjected to in fourpoint
bending to comply with the laboratory tests. Since laboratory
measurements of local elastic moduli may in general suffer from a
significant experimental error, it appears advantageous to exploit the
full scale measurements of timber beams, i.e. deflections, to improve
their prior distributions with the help of the Bayesian statistical
method. This, however, requires an efficient computational model
when simulating the laboratory tests numerically. To this end, a
simplified model based on Mindlin’s beam theory was established.
The improved posterior distributions show that the most significant
change of the Young’s modulus distribution takes place in laminae in
the most strained zones, i.e. in the top and bottom layers within the
beam center region. Posterior distributions of moduli of elasticity
were subsequently utilized in the 2D FEM model and compared with
the original simulations.
Abstract: An experimental study was performed to investigate
the behavior and strength of proposed technique to connect
reinforced concrete (RC) beam to steel or composite columns. This
approach can practically be used in several types of building
construction. In this technique, the main beam of the frame consists
of a transfer part (part of beam; Tr.P) and a common reinforcement
concrete beam. The transfer part of the beam is connected to the
column, whereas the rest of the beam is connected to the transfer part
from each side. Four full-scale beam-column connections were tested
under static loading. The test parameters were the length of the
transfer part and the column properties. The test results show that
using of the transfer part technique leads to modify the deformation
capabilities for the RC beam and hence it increases its resistance
against failure. Increase in length of the transfer part did not
necessarily indicate an enhanced behavior. The test results contribute
to the characterization of the connection behavior between RC beam -
steel column and can be used to calibrate numerical models for the
simulation of this type of connection.
Abstract: The explosion of the World Wide Web and the
electronic trend of university teaching have transformed the learning
style to become more learner-centered, which has popularized the
digital delivery of mediated lectures as an alternative or an adjunct to
traditional lectures. Despite its potential and popularity, virtual
lectures have not been adopted yet in Jordanian universities. This
research aimed to fill this gap by studying the factors that influence
students’ willingness to accept virtual lectures in one Jordanian
University. A quantitative approach was followed, by obtaining 216
survey responses and statistically applying the UTAUT model with
some modifications. Results revealed that performance expectancy,
effort expectancy, social influences, and self-efficacy could
significantly influence students’ attitudes towards virtual lectures.
Additionally, Facilitating conditions and attitudes towards virtual
lectures were found with significant influence on students’ intention
to take virtual lectures. Research implications and future work were
specified afterwards.
Abstract: This paper introduces a proposal scheme for an
Intelligent System applied to Pedagogical Advising using Case-Based
Reasoning, to find consolidated solutions before used for the new
problems, making easier the task of advising students to the
pedagogical staff. We do intend, through this work, introduce the
motivation behind the choices for this system structure, justifying the
development of an incremental and smart web system who learns
bests solutions for new cases when it’s used, showing technics and
technology.
Abstract: In this study, the Compressive strength of concretes
made with Ground Granulated Blast furnace Slag (GGBS),
Pulverised Fuel Ash (PFA), Rice Husk Ash (RHA) and Waste Glass
Powder (WGP) after they were exposed 7800C (exposure duration of
around 60 minutes) and then allowed to cool down gradually in the
furnace for about 280 minutes at water binder ratio of 0.50 was
investigated. GGBS, PFA, RHA and WGP were used to replace up to
20% Portland cement in the control concrete. Test for the
determination of workability, compressive strength and tensile
splitting strength of the concretes were carried out and the results
were compared with control concrete. The test results showed that the
compressive strength decreased by an average of around 30% after
the concretes were exposed to the heating and cooling scenario.
Abstract: Catalytic combustion of methane is imperative due to
stability of methane at low temperature. Methane (CH4), therefore,
remains unconverted in vehicle exhausts thereby causing greenhouse
gas GHG emission problem. In this study, heterogeneous catalysts of
palladium with bio-char (2 wt% Pd/Bc) and Al2O3 (2wt% Pd/ Al2O3)
supports were prepared by incipient wetness impregnation and then
subsequently tested for catalytic combustion of CH4. Support-porous
heterogeneous catalytic combustion (HCC) material were selected
based on factors such as surface area, porosity, thermal stability,
thermal conductivity, reactivity with reactants or products, chemical
stability, catalytic activity, and catalyst life. Sustainable and
renewable support-material of bio-mass char derived from palm shell
waste material was compared with those from the conventional
support-porous materials. Kinetic rate of reaction was determined for
combustion of methane on Palladium (Pd) based catalyst with Al2O3
support and bio-char (Bc). Material characterization was done using
TGA, SEM, and BET surface area. The performance test was
accomplished using tubular quartz reactor with gas mixture ratio of
3% methane and 97% air. The methane porous-HCC conversion was
carried out using online gas analyzer connected to the reactor that
performed porous-HCC. BET surface area for prepared 2 wt% Pd/Bc
is smaller than prepared 2wt% Pd/ Al2O3 due to its low porosity
between particles. The order of catalyst activity based on kinetic rate
on reaction of catalysts in low temperature was 2wt%
Pd/Bc>calcined 2wt% Pd/ Al2O3> 2wt% Pd/ Al2O3>calcined 2wt%
Pd/Bc. Hence agro waste material can successfully be utilized as an
inexpensive catalyst support material for enhanced CH4 catalytic
combustion.
Abstract: Adolescents with Autism Spectrum Disorders (ASD)
often experience social-communication difficulties that negatively
impact their social interactions with typical peers. However, unlike
other age and disability groups, there is little intervention research to
inform best practice for these students. One evidence-based strategy
for younger students with ASD is peer-mediated intervention (PMI).
PMI may be particularly promising for use with adolescents, as peers
are readily available and are natural experts for encouraging authentic
high school conversations. This paper provides a review of previous
research that evaluated the use of PMI to improve the socialcommunication
skills of students with ASD. Specific intervention
features associated with positive student outcomes are identified and
recommendations for future research are provided. Adolescents with
ASD are targeted due the critical importance of social conversation at
the high school level.
Abstract: This paper proposes five level diode clamped Z source
Inverter. The existing PWM techniques used for ZSI are restricted for
two level. The two level Z Source Inverter have high harmonic
distortions which effects the performance of the grid connected PV
system. To improve the performance of the system the number of
voltage levels in the output waveform need to be increased. This
paper presents comparative analysis of a five level diode clamped Z
source Inverter with different carrier based Modified Pulse Width
Modulation techniques. The parameters considered for comparison
are output voltage, voltage gain, voltage stress across switch and total
harmonic distortion when powered by same DC supply. Analytical
results are verified using MATLAB.
Abstract: Most people today are aware that global climate
change is not just a scientific theory but also a fact with worldwide
consequences. Global climate change is due to rapid urbanization,
industrialization, high population growth and current vulnerability of
the climatic condition. Water is becoming scarce as a result of global
climate change. To mitigate the problem arising due to global climate
change and its drought effect, harvesting rainwater from green roofs,
an environmentally-friendly and versatile technology, is becoming
one of the best assessment criteria and gaining attention in Malaysia.
This paper addresses the sustainability of green roofs and examines
the quality of water harvested from green roofs in comparison to
rainwater. The factors that affect the quality of such water, taking
into account, for example, roofing materials, climatic conditions, the
frequency of rainfall frequency and the first flush. A green roof was
installed on the Humid Tropic Centre (HTC) is a place of the study
on monitoring program for urban Stormwater Management Manual
for Malaysia (MSMA), Eco-Hydrological Project in Kuala Lumpur,
and the rainwater was harvested and evaluated on the basis of four
parameters i.e., conductivity, dissolved oxygen (DO), pH and
temperature. These parameters were found to fall between Class I and
Class III of the Interim National Water Quality Standards (INWQS)
and the Water Quality Index (WQI). Some preliminary treatment
such as disinfection and filtration could likely to improve the value of
these parameters to class I. This review paper clearly indicates that
there is a need for more research to address other microbiological and
chemical quality parameters to ensure that the harvested water is
suitable for use potable water for domestic purposes. The change in
all physical, chemical and microbiological parameters with respect to
storage time will be a major focus of future studies in this field.
Abstract: Array-based gene expression analysis is a powerful
tool to profile expression of genes and to generate information on
therapeutic effects of new anti-cancer compounds. Anti-apoptotic
effect of thymoquinone was studied in MCF7 breast cancer cell line
using gene expression profiling with cDNA microarray. The purity
and yield of RNA samples were determined using RNeasyPlus Mini
kit. The Agilent RNA 6000 NanoLabChip kit evaluated the quantity
of the RNA samples. AffinityScript RT oligo-dT promoter primer
was used to generate cDNA strands. T7 RNA polymerase was used to
convert cDNA to cRNA. The cRNA samples and human universal
reference RNA were labelled with Cy-3-CTP and Cy-5-CTP,
respectively. Feature Extraction and GeneSpring softwares analysed
the data. The single experiment analysis revealed involvement of 64
pathways with up-regulated genes and 78 pathways with downregulated
genes. The MAPK and p38-MAPK pathways were
inhibited due to the up-regulation of PTPRR gene. The inhibition of
p38-MAPK suggested up-regulation of TGF-ß pathway. Inhibition of
p38-MAPK caused up-regulation of TP53 and down-regulation of
Bcl2 genes indicating involvement of intrinsic apoptotic pathway.
Down-regulation of CARD16 gene as an adaptor molecule regulated
CASP1 and suggested necrosis-like programmed cell death and
involvement of caspase in apoptosis. Furthermore, down-regulation
of GPCR, EGF-EGFR signalling pathways suggested reduction of
ER. Involvement of AhR pathway which control cytochrome P450
and glucuronidation pathways showed metabolism of Thymoquinone.
The findings showed differential expression of several genes in
apoptosis pathways with thymoquinone treatment in estrogen
receptor-positive breast cancer cells.
Abstract: The check-in area of airport terminal is one of the
busiest sections at airports at certain periods. The passengers are
subjected to queues and delays during the check-in process. These
delays and queues are due to constraints in the capacity of service
facilities. In this project, the airport terminal is decomposed into
several check-in areas. The airport check-in scheduling problem
requires both a deterministic (integer programming) and stochastic
(simulation) approach. Integer programming formulations are
provided to minimize the total number of counters in each check-in
area under the realistic constraint that counters for one and the same
flight should be adjacent and the desired number of counters
remaining in each area should be fixed during check-in operations.
By using simulation, the airport system can be modeled to study the
effects of various parameters such as number of passengers on a
flight and check-in counter opening and closing time.
Abstract: We assessed the ecology of the organic and mineral soil
layers of laurel-leaved (BB-1) and Cryptomeria japonica (BB-2 and Pw)
forests in the Kasugayama Hill Primeval Forest (Nara, Japan). The soil
respiration rate was higher in the deeper horizons (F and H) of organic
layers than in those of mineral soil layers, suggesting organic layers
may be where active microbial metabolism occurs. Respiration rates in
the soil of BB-1, BB-2 and Pw forests were closely similar at 5 and 10°C.
However, the soil respiration rate increased in proportion to
temperatures of 15°C or above. We therefore consider the activity of
soil microorganisms to markedly decrease at temperatures below 10°C.
At a temperature of 15°C or above, the soil respiration rate in the BB-1
organic layers was higher than in those of the BB-2 and Pw organic
layers, due to differences in forest vegetation that appeared to
influence several salient soil properties, particularly pH and the carbon
(C) and nitrogen (N) content of the F and H horizons.
Abstract: In the past few decades, the field of chemistry
education has grown tremendously and researches indicated that after
traditional chemistry instruction students often lacked deep
conceptual understanding and failed to integrate their ideas into
coherent conceptual framework. For several concepts in chemistry,
students at all levels have demonstrated difficulty in changing their
initial perceptions. Their perceptions are most often wrong and don't
agree with correct scientific concepts. This study explored the
effectiveness of intervention discussion sections for a college general
chemistry course designed to apply research on students
preconceptions, knowledge integration and student explanation.
Three interventions discussions lasting three hours on bond energy
and spontaneity were done tested and intervention (treatment)
students’ performances were compared with that of control group
which did not use the experimental pedagogy. Results indicated that
this instruction which was capable of identifying students'
misconceptions, initial conceptions and integrating those ideas into
class discussion led to enhanced conceptual understanding and better
achievement for the experimental group.
Abstract: Nitrogen fertilizer is the most used and often the most
mismanaged nutrient input. Nitrogen management has tremendous
implications on crop productivity, quality and environmental
stewardship. Sufficient nitrogen is needed to optimum yield and
quality. Soil and in-season plant tissue testing for nitrogen status are
a time consuming and expensive process. Real time sensing of plant
nitrogen status can be a useful tool in managing nitrogen inputs. The
objectives of this project were to assess the reliability of remotely
sensed non-destructive plant nitrogen measurements compared to wet
chemistry data from sampled plant tissue, develop in-season nitrogen
recommendations based on remotely sensed data for improved
nitrogen use efficiency and assess the potential for determining yield
and quality from remotely sensed data. Very good correlations were
observed between early-season remotely sensed crop nitrogen status
and plant nitrogen concentrations and subsequent in-season fertilizer
recommendations. The transmittance/absorbance type meters gave
the most accurate readings. Early in-season fertilizer recommendation
would be to apply 40 kg nitrogen per hectare plus 15 kg nitrogen per
hectare for each unit difference measured with the SPAD meter
between the crop and reference area or 25 kg plus 13 kg per hectare
for each unit difference measured with the CCM 200. Once the crop
was sufficiently fertilized meter readings became inconclusive and
were of no benefit for determining nitrogen status, silage yield and
quality and grain yield and protein.
Abstract: The Al-MoO3-P-CdTe-Al MOS sandwich structures
were fabricated by vacuum deposition method on cleaned glass
substrates. Capacitance versus voltage measurements were performed
at different frequencies and sweep rates of applied voltages for oxide
and semiconductor films of different thicknesses. In the negative
voltage region of the C-V curve a high differential capacitance of the
semiconductor was observed and at high frequencies (
Abstract: Chemical vapor deposition (CVD) diamond coated
cutting tool has excellent cutting performance, it is the most ideal tool
for the processing of nonferrous metals and alloys, composites,
nonmetallic materials and other difficult-to-machine materials
efficiently and accurately. Depositing CVD diamond coating on the
cemented carbide with high cobalt content can improve its toughness
and strength, therefore, it is very important to research on the
preparation technology and cutting properties of CVD diamond coated
cemented carbide cutting tool with high cobalt content. The
preparation technology of boron-doped diamond (BDD) coating has
been studied and the coated drills were prepared. BDD coating were
deposited on the drills by using the optimized parameters and the SEM
results show that there are no cracks or collapses in the coating.
Cutting tests with the prepared drills against the silumin and aluminum
base printed circuit board (PCB) have been studied. The results show
that the wear amount of the coated drill is small and the machined
surface has a better precision. The coating does not come off during
the test, which shows good adhesion and cutting performance of the
drill.
Abstract: Solid waste management in steel industry is broadly
classified in “4 Rs” i.e. reduce, reuse, recycle and restore the
materials. Reuse and recycling the entire solid waste generated in the
process of steel making is a viable solution in targeting a clean, green
and zero waste technology leading to sustainable development of the
steel industry. Solid waste management has gained importance in
steel industry in view of its uncertainty, volatility and speculation due
to world competitive standards, rising input costs, scarcity of raw
materials and solid waste generated like in other sectors. The
challenges that the steel Industry faces today are the requirement of a
sustainable development by meeting the needs of our present
generation without compromising the ability of future generations.
Technologies are developed not only for gainful utilization of solid
wastes in manufacture of conventional products but also for
conversion of same in to completely new products.
Abstract: Hybrid bioreactor having both suspended-growth and
attached-growth bacteria is found a novel and excellent bioreactor
system for treating the municipal wastewater containing inhibitory
substrates too. In this reactor a fraction of substrate is used by
suspended biomass and the remaining by attached biomass resulting
in the competition between the two growths for the substrate. The
combination of suspended and attached growth provides the system
with enhanced biomass concentration and sludge age more than those
in ASP. Similar to attached growth system, the hybrid bioreactor
ensures considerable efficiency for treating toxic and refractory
substances in wastewater. For the process design of hybrid bioreactor
a suitable mathematical model is required. Although various
mathematical models were developed on hybrid bioreactor in due
course of time in earlier research works, none of them was found
having a specific simplified solution of the corresponding models and
without having any drawback. To overcome this drawback authors
already developed a simplified mathematical model for process
design of a hybrid bioreactor. The present paper briefly highlights on
the various aspects of process design of an aerobic hybrid bioreactor
for the treatment of municipal wastewater.
Abstract: The capability of CNC gantry milling machines in
manufacturing long components has caused the expanded use of such
machines. On the other hand, the machines’ gantry rigidity can
reduce under severe loads or vibration during operation. Indeed, the
quality of machining is dependent on the machine’s dynamic
behavior throughout the operating process. For this reason, these
types of machines have always been used widely and are not
efficient. Therefore, they can usually be employed for rough
machining and may not produce adequate surface finishing. In this
paper, a CNC gantry milling machine with the potential to produce
good surface finish has been designed and analyzed. The lowest
natural frequency of this machine is 202 Hz corresponding to 12000
rpm at all motion amplitudes with a full range of suitable frequency
responses. Meanwhile, the maximum deformation under dead loads
for the gantry machine is 0.565*m, indicating that this machine tool
is capable of producing higher product quality.
Abstract: The main aim of the presented experiments is to
improve behaviour of sandwich structures under dynamic loading,
such as crash or explosion. This paper describes experimental
investigation on the response of new advanced materials to low and
high velocity load. Blast wave energy absorbers were designed using
two types of porous lightweight raw particle materials based on
expanded glass and ceramics with dimensions of 0.5-1 mm,
combined with polymeric binder. The effect of binder amount on the
static and dynamic properties of designed materials was observed.
Prism shaped specimens were prepared and loaded to obtain physicomechanical
parameters – bulk density, compressive and flexural
strength under quasistatic load, the dynamic response was determined
using Split Hopkinson Pressure bar apparatus. Numerical
investigation of the material behaviour in sandwich structure was
performed using implicit/explicit solver LS-Dyna. As the last step,
the developed material was used as the interlayer of blast resistant
litter bin, and it´s functionality was verified by real field blast tests.