Abstract: The purposes of hydraulic gate are to maintain the
functions of storing and draining water. It bears long-term hydraulic
pressure and earthquake force and is very important for reservoir and
waterpower plant. The high tensile strength of steel plate is used as
constructional material of hydraulic gate. The cracks and rusts,
induced by the defects of material, bad construction and seismic
excitation and under water respectively, thus, the mechanics
phenomena of gate with crack are probing into the cause of stress
concentration, induced high crack increase rate, affect the safety and
usage of hydroelectric power plant. Stress distribution analysis is a
very important and essential surveying technique to analyze
bi-material and singular point problems. The finite difference
infinitely small element method has been demonstrated, suitable for
analyzing the buckling phenomena of welding seam and steel plate
with crack. Especially, this method can easily analyze the singularity
of kink crack. Nevertheless, the construction form and deformation
shape of some gates are three-dimensional system. Therefore, the
three-dimensional Digital Image Correlation (DIC) has been
developed and applied to analyze the strain variation of steel plate with
crack at weld joint. The proposed Digital image correlation (DIC)
technique is an only non-contact method for measuring the variation of
test object. According to rapid development of digital camera, the cost
of this digital image correlation technique has been reduced.
Otherwise, this DIC method provides with the advantages of widely
practical application of indoor test and field test without the restriction
on the size of test object. Thus, the research purpose of this research is
to develop and apply this technique to monitor mechanics crack
variations of weld steel hydraulic gate and its conformation under
action of loading. The imagines can be picked from real time
monitoring process to analyze the strain change of each loading stage.
The proposed 3-Dimensional digital image correlation method,
developed in the study, is applied to analyze the post-buckling
phenomenon and buckling tendency of welded steel plate with crack.
Then, the stress intensity of 3-dimensional analysis of different
materials and enhanced materials in steel plate has been analyzed in
this paper. The test results show that this proposed three-dimensional
DIC method can precisely detect the crack variation of welded steel
plate under different loading stages. Especially, this proposed DIC
method can detect and identify the crack position and the other flaws
of the welded steel plate that the traditional test methods hardly detect
these kind phenomena. Therefore, this proposed three-dimensional
DIC method can apply to observe the mechanics phenomena of
composite materials subjected to loading and operating.
Abstract: A Multi-dimensional computational fluid dynamics
(CFD) two-phase model was developed with the aim to simulate
the in-core coolant circuit of a pressurized heavy water reactor
(PHWR) of a commercial nuclear power plant (NPP). Due to the
fact that this PHWR is a Reactor Pressure Vessel type (RPV),
three-dimensional (3D) detailed modelling of the large reservoirs of
the RPV (the upper and lower plenums and the downcomer) were
coupled with an in-house finite volume one-dimensional (1D) code
in order to model the 451 coolant channels housing the nuclear fuel.
Regarding the 1D code, suitable empirical correlations for taking into
account the in-channel distributed (friction losses) and concentrated
(spacer grids, inlet and outlet throttles) pressure losses were used.
A local power distribution at each one of the coolant channels
was also taken into account. The heat transfer between the coolant
and the surrounding moderator was accurately calculated using a
two-dimensional theoretical model. The implementation of subcooled
boiling and condensation models in the 1D code along with the use
of functions for representing the thermal and dynamic properties of
the coolant and moderator (heavy water) allow to have estimations
of the in-core steam generation under nominal flow conditions for a
generic fission power distribution. The in-core mass flow distribution
results for steady state nominal conditions are in agreement with the
expected from design, thus getting a first assessment of the coupled
1/3D model. Results for nominal condition were compared with
those obtained with a previous 1/3D single-phase model getting more
realistic temperature patterns, also allowing visualize low values of
void fraction inside the upper plenum. It must be mentioned that the
current results were obtained by imposing prescribed fission power
functions from literature. Therefore, results are showed with the aim
of point out the potentiality of the developed model.
Abstract: The education sector is constantly faced with rapid
changes in technologies in terms of ensuring that the curriculum is up
to date and in terms of making sure that students are aware of these
technological changes. This challenge can be seen as the motivation
for this study, which is to examine the factors affecting computing
students’ awareness of the latest Information Technologies (ICTs).
The aim of this study is divided into two sub-objectives which are:
the selection of relevant theories and the design of a conceptual
model to support it as well as the empirical testing of the designed
model. The first objective is achieved by a review of existing
literature on technology adoption theories and models. The second
objective is achieved using a survey of computing students in the four
universities of the KwaZulu-Natal province of South Africa. Data
collected from this survey is analyzed using Statistical package for
the Social Science (SPSS) using descriptive statistics, ANOVA and
Pearson correlations. The main hypothesis of this study is that there is
a relationship between the demographics and the prior conditions of
the computing students and their awareness of general ICT trends and
of Digital Switch Over (DSO) a new technology which involves the
change from analog to digital television broadcasting in order to
achieve improved spectrum efficiency. The prior conditions of the
computing students that were considered in this study are students’
perceived exposure to career guidance and students’ perceived
curriculum currency. The results of this study confirm that gender,
ethnicity, and high school computing course affect students’
perceived curriculum currency while high school location affects
students’ awareness of DSO. The results of this study also confirm
that there is a relationship between students prior conditions and their
awareness of general ICT trends and DSO in particular.
Abstract: A retrospective study conducted at Christian Medical
College (CMC) Teaching Hospital, Vellore, India on 14th August
2014 to assess the accuracy of clinically estimated foetal weight upon
labour admission. Estimating foetal weight is a crucial factor in
assessing maternal and foetal complications during and after labour.
Medical notes of ninety-eight postnatal women who fulfilled the
inclusion criteria were studied to evaluate the correlation between
their recorded Estimated Foetal Weight (EFW) on admission and
actual birth weight (ABW) of the newborn after delivery. Data
concerning maternal and foetal demographics was also noted.
Accuracy was determined by absolute percentage error and
proportion of estimates within 10% of ABW. Actual birth weights
ranged from 950-4080g. A strong positive correlation between EFW
and ABW (r=0.904) was noted. Term deliveries (≥40 weeks) in the
normal weight range (2500-4000g) had a 59.5% estimation accuracy
(n=74) compared to pre-term (4000g) were underestimated by 25% (n=3) and low birthweight
(LBW) babies were overestimated by 12.7% (n=9). Registrars who
estimated foetal weight were accurate in babies within normal weight
ranges. However, there needs to be an improvement in predicting
weight of macrosomic and LBW foetuses. We have suggested the use
of an amended version of the Johnson’s formula for the Indian
population for improvement and a need to re-audit once
implemented.
Abstract: Polycyclic Aromatic Hydrocarbons (PAHs) are
formed mainly because of incomplete combustion of organic
materials during industrial, domestic activities or natural occurrence.
Their toxicity and contamination of terrestrial and aquatic ecosystem
have been established. However, with limited validity index, previous
research has focused on PAHs isomer pair ratios of variable
physicochemical properties in source identification. The objective of
this investigation was to determine the empirical validity of Pearson
Correlation Coefficient (PCC) and Cluster Analysis (CA) in PAHs
source identification along soil samples of different land uses.
Therefore, 16 PAHs grouped, as Endocrine Disruption Substances
(EDSs) were determined in 10 sample stations in top and sub soils
seasonally. PAHs was determined the use of Varian 300 gas
chromatograph interfaced with flame ionization detector. Instruments
and reagents used are of standard and chromatographic grades
respectively. PCC and CA results showed that the classification of
PAHs along pyrolitic and petrogenic organics used in source
signature is about the predominance PAHs in environmental matrix.
Therefore, the distribution of PAHs in the studied stations revealed
the presence of trace quantities of the vast majority of the sixteen
PAHs, which may ultimately inhabit the actual source signature
authentication. Therefore, factors to be considered when evaluating
possible sources of PAHs could be; type and extent of bacterial
metabolism, transformation products/substrates, and environmental
factors such as salinity, pH, oxygen concentration, nutrients, light
intensity, temperature, co-substrates, and environmental medium are
hereby recommended as factors to be considered when evaluating
possible sources of PAHs.
Abstract: Polymorphism is one of the main pillars of objectoriented
paradigm. It induces hidden forms of class dependencies
which may impact software quality, resulting in higher cost factor for
comprehending, debugging, testing, and maintaining the software. In
this paper, a new cognitive complexity metric called Cognitive
Weighted Polymorphism Factor (CWPF) is proposed. Apart from the
software structural complexity, it includes the cognitive complexity
on the basis of type. The cognitive weights are calibrated based on 27
empirical studies with 120 persons. A case study and experimentation
of the new software metric shows positive results. Further, a
comparative study is made and the correlation test has proved that
CWPF complexity metric is a better, more comprehensive, and more
realistic indicator of the software complexity than Abreu’s
Polymorphism Factor (PF) complexity metric.
Abstract: This study was conducted to investigate the
psychological variables motivating sport participation and
involvement among student-athletes of tertiary institutions in southwest
Nigeria. One thousand three hundred and fifty (N-1350) studentathletes
were randomly selected in all sports from nine tertiary
institutions in south-west Nigeria. These tertiary institutions include
University of Lagos, Lagos State University, Obafemi Awolowo
University, Osun State University, University of Ibadan, University
of Agriculture Abeokuta, Federal University of Technology
Akungba, University of Ilorin, and Kwara State University. The
descriptive survey research method was adopted while a self
developed validated Likert type questionnaire named Sport
Participation Scale (SPS) was used to elicit opinion from
respondents. The test-retest reliability value obtained for the
instrument, using Pearson Product Moment Correlation Co-efficient
was 0.96. Out of the one thousand three hundred and fifty (N-1350)
questionnaire administered, only one thousand two hundred and five
(N-1286) were correctly filled, coded and analysed using inferential
statistics of Chi-Square (X2) while all the tested hypotheses were set
at. 05 alpha level. Based on the findings of this study, the result
revealed that several psychological factors influence student athletes
to continue participation in sport one which includes love for the
game, famous athletes as role model and family support. However,
the analysis further revealed that the stipends the student-athletes get
from their universities have no influence on their participation and
involvement in sport.
Abstract: Recent investigations have demonstrated the global
sea level rise due to climate change impacts. In this study, climate
changes study the effects of increasing water level in the strait of
Hormuz. The probable changes of sea level rise should be
investigated to employ the adaption strategies. The climatic output
data of a GCM (General Circulation Model) named CGCM3 under
climate change scenario of A1b and A2 were used. Among different
variables simulated by this model, those of maximum correlation
with sea level changes in the study region and least redundancy
among themselves were selected for sea level rise prediction by using
stepwise regression. One of models (Discrete Wavelet artificial
Neural Network) was developed to explore the relationship between
climatic variables and sea level changes. In these models, wavelet
was used to disaggregate the time series of input and output data into
different components and then ANN was used to relate the
disaggregated components of predictors and input parameters to each
other. The results showed in the Shahid Rajae Station for scenario
A1B sea level rise is among 64 to 75 cm and for the A2 Scenario sea
level rise is among 90 t0 105 cm. Furthermore, the result showed a
significant increase of sea level at the study region under climate
change impacts, which should be incorporated in coastal areas
management.
Abstract: Presently various computational techniques are used
in modeling and analyzing environmental engineering data. In the
present study, an intra-comparison of polynomial and radial basis
kernel functions based on Support Vector Regression and, in turn, an
inter-comparison with Multi Linear Regression has been attempted in
modeling mass transfer capacity of vertical (θ = 90O) and inclined (θ
multiple plunging jets (varying from 1 to 16 numbers). The data set
used in this study consists of four input parameters with a total of
eighty eight cases, forty four each for vertical and inclined multiple
plunging jets. For testing, tenfold cross validation was used.
Correlation coefficient values of 0.971 and 0.981 along with
corresponding root mean square error values of 0.0025 and 0.0020
were achieved by using polynomial and radial basis kernel functions
based Support Vector Regression respectively. An intra-comparison
suggests improved performance by radial basis function in
comparison to polynomial kernel based Support Vector Regression.
Further, an inter-comparison with Multi Linear Regression
(correlation coefficient = 0.973 and root mean square error = 0.0024)
reveals that radial basis kernel functions based Support Vector
Regression performs better in modeling and estimating mass transfer
by multiple plunging jets.
Abstract: Graphene, a single-atom sheet, has been considered as
the most promising material for making future nanoelectromechanical
systems as well as purely electrical switching with graphene
transistors. Graphene-based devices have advantages in scaled-up
device fabrication due to the recent progress in large area graphene
growth and lithographic patterning of graphene nanostructures. Here
we investigated its mechanical responses of circular graphene
nanoflake under the nanoindentation using classical molecular
dynamics simulations. A correlation between the load and the
indentation depth was constructed. The nanoindented force in this
work was applied to the center point of the circular graphene nanoflake
and then, the resonance frequency could be tuned by a nanoindented
depth. We found the hardening or the softening of the graphene
nanoflake during its nanoindented-deflections, and such properties
were recognized by the shift of the resonance frequency. The
calculated mechanical parameters in the force-vs-deflection plot were
in good agreement with previous experimental and theoretical works.
This proposed schematics can detect the pressure via the deflection
change or/and the resonance frequency shift, and also have great
potential for versatile applications in nanoelectromechanical systems.
Abstract: The goal of this paper is proposing a supply chain
value dashboard in home appliance manufacturing firms to create
more value for all stakeholders via balanced scorecard approach.
Balanced scorecard is an effective approach that managers have used
to evaluate supply chain performance in many fields but there is a
lack of enough attention to all supply chain stakeholders, improving
value creation and, defining correlation between value indicators and
performance measuring quantitatively. In this research the key
stakeholders in home appliance supply chain, value indicators with
respect to create more value for stakeholders and the most important
metrics to evaluate supply chain value performance based on
balanced scorecard approach have been selected via literature review.
The most important indicators based on expert’s judgment acquired
by in survey focused on creating more value for. Structural equation
modelling has been used to disclose relations between value
indicators and balanced scorecard metrics. The important result of
this research is identifying effective value dashboard to create more
value for all stakeholders in supply chain via balanced scorecard
approach and based on an empirical study covering ten home
appliance manufacturing firms in Iran. Home appliance
manufacturing firms can increase their stakeholder's satisfaction by
using this value dashboard.
Abstract: Here, we have shown the reaction of [Cr(ArN(CH2)3NAr)2Cl2] (1) where (Ar = 2,6-Pri
2C6H3) and in presence of NaCp (2) (Cp= C5H5 = cyclopentadien), with a center
coordination η5 interaction between Cp as co-ligand and chromium
metal center, for optimization we used density functional theory
(DFT), under methods, explicitly including electrons correlations, for
the final calculations as MB3LYP (Becke) (Lee–Yang–Parr) level of
theory we used to obtain more exact results. This complex was
calculated as electronic energy for molecular system, because the
calculation accounting all electrons correlations interactions. The
optimised of [Cr(ArN(CH2)3NAr)2(η5-Cp)] (Ar = 2,6-Pri2C6H3 and Cp = C5H5) was found to be thermally stable. By using Dewar-Chatt-Duncanson model, as a basis of the molecular orbital (MO) analysis
and showed the highest occupied molecular orbital (HOMO) and
lowest occupied molecular orbital LUMO.
Abstract: The need to save time and cost of soil testing at the
planning stage of road work has necessitated developing predictive
models. This study proposes a model for predicting the dry density of
lateritic soils stabilized with corn cob ash (CCA) and blended cement
- CCA. Lateritic soil was first stabilized with CCA at 1.5, 3.0, 4.5 and
6% of the weight of soil and then stabilized with the same
proportions as replacement for cement. Dry density, specific gravity,
maximum degree of saturation and moisture content were determined
for each stabilized soil specimen, following standard procedure.
Polynomial equations containing alpha and beta parameters for CCA
and blended CCA-cement were developed. Experimental values were
correlated with the values predicted from the Matlab curve fitting
tool, and the Solver function of Microsoft Excel 2010. The correlation
coefficient (R2) of 0.86 was obtained indicating that the model could
be accepted in predicting the maximum dry density of CCA stabilized
soils to facilitate quick decision making in roadworks.
Abstract: This article presents the main results of a numerical
investigation on the uncertainty of dynamic response of structures
with statistically correlated random damping Gamma distributed. A
computational method based on a Linear Statistical Model (LSM) is
implemented to predict second order statistics for the response of a
typical industrial building structure. The significance of random
damping with correlated parameters and its implications on the
sensitivity of structural peak response in the neighborhood of a
resonant frequency are discussed in light of considerable ranges of
damping uncertainties and correlation coefficients. The results are
compared to those generated using Monte Carlo simulation
techniques. The numerical results obtained show the importance of
damping uncertainty and statistical correlation of damping
coefficients when obtaining accurate probabilistic estimates of
dynamic response of structures. Furthermore, the effectiveness of the
LSM model to efficiently predict uncertainty propagation for
structural dynamic problems with correlated damping parameters is
demonstrated.
Abstract: The aim of this study was to determine the factor
structure and psychometric properties (i.e., reliability and convergent
validity) of the Employee Trust Scale, a newly created instrument by
the researchers. The Employee Trust Scale initially contained 82
items to measure employees’ trust toward their supervisors. A sample
of 818 (343 females, 449 males) employees were selected randomly
from public and private organization sectors in Kota Kinabalu,
Sabah, Malaysia. Their ages ranged from 19 to 67 years old with a
mean of 34.55 years old. Their average tenure with their current
employer was 11.2 years (s.d. = 7.5 years). The respondents were
asked to complete the Employee Trust Scale, as well as a managerial
trust questionnaire from Mishra. The exploratory factor analysis on
employees’ trust toward their supervisor’s extracted three factors,
labeled ‘trustworthiness’ (32 items), ‘position status’ (11 items) and
‘relationship’ (6 items) which accounted for 62.49% of the total
variance. Trustworthiness factors were re-categorized into three sub
factors: competency (11 items), benevolence (8 items) and integrity
(13 items). All factors and sub factors of the scales demonstrated
clear reliability with internal consistency of Cronbach’s Alpha above
.85. The convergent validity of the Scale was supported by an
expected pattern of correlations (positive and significant correlation)
between the score of all factors and sub factors of the scale and the
score on the managerial trust questionnaire, which measured the same
construct. The convergent validity of Employee Trust Scale was
further supported by the significant and positive inter-correlation
between the factors and sub factors of the scale. The results suggest
that the Employee Trust Scale is a reliable and valid measure.
However, further studies need to be carried out in other groups of
sample as to further validate the Scale.
Abstract: Carbon Fiber Reinforced Plastics (CFRPs) are widely
used for advanced applications, in particular in aerospace, automotive
and wind energy industries. Once cured to near net shape, CFRP
parts need several finishing operations such as trimming, milling or
drilling in order to accommodate fastening hardware and meeting the
final dimensions. The present research aims to study the effect of the
cutting temperature in trimming on the mechanical strength of high
performance CFRP laminates used for aeronautics applications. The
cutting temperature is of great importance when dealing with
trimming of CFRP. Temperatures higher than the glass-transition
temperature (Tg) of the resin matrix are highly undesirable: they
cause degradation of the matrix in the trimmed edges area, which can
severely affect the mechanical performance of the entire component.
In this study, a 9.50mm diameter CVD diamond coated carbide tool
with six flutes was used to trim 24-plies CFRP laminates. A
300m/min cutting speed and 1140mm/min feed rate were used in the
experiments. The tool was heated prior to trimming using a
blowtorch, for temperatures ranging from 20°C to 300°C. The
temperature at the cutting edge was measured using embedded KType
thermocouples. Samples trimmed for different cutting
temperatures, below and above Tg, were mechanically tested using
three-points bending short-beam loading configurations. New cutting
tools as well as worn cutting tools were utilized for the experiments.
The experiments with the new tools could not prove any correlation
between the length of cut, the cutting temperature and the mechanical
performance. Thus mechanical strength was constant, regardless of
the cutting temperature. However, for worn tools, producing a cutting
temperature rising up to 450°C, thermal damage of the resin was
observed. The mechanical tests showed a reduced mean resistance in
short beam configuration, while the resistance in three point bending
decreases with increase of the cutting temperature.
Abstract: Our sowing date experiment took place in the
Demonstration Garden of Institution of Plant Sciences, Centre for
Agricultural Sciences of University of Debrecen, in 2012-2014. The
paper contains data of test year 2014. Our purpose, besides several
other examinations, was to observe how sowing date influences the
leaf area index and the activity of photosynthesis of maize hybrids,
and how those factors affect fruiting. In the experiment we monitored
the change of the leaf area index and the photosynthesis of hybrids
with four different growing seasons. The results obtained confirm
that not only the environmental and agricultural factors in the
growing season have effect on the yield, but also other factors like
the leaf area index and the photosynthesis are determinative
parameters, and all those factors together, modifying the effects of
each other, develop average yields.
Abstract: This article presents an alternative collapse capacity
intensity measure in the three elements form which is influenced by
the spectral ordinates at periods longer than that of the first mode
period at near and far source sites. A parameter, denoted by β, is
defined by which the spectral ordinate effects, up to the effective
period (2T1), on the intensity measure are taken into account. The
methodology permits to meet the hazard-levelled target extreme
event in the probabilistic and deterministic forms. A MATLAB code
is developed involving OpenSees to calculate the collapse capacities
of the 8 archetype RC structures having 2 to 20 stories for regression
process. The incremental dynamic analysis (IDA) method is used to
calculate the structure’s collapse values accounting for the element
stiffness and strength deterioration. The general near field set
presented by FEMA is used in a series of performing nonlinear
analyses. 8 linear relationships are developed for the 8structutres
leading to the correlation coefficient up to 0.93. A collapse capacity
near field prediction equation is developed taking into account the
results of regression processes obtained from the 8 structures. The
proposed prediction equation is validated against a set of actual near
field records leading to a good agreement. Implementation of the
proposed equation to the four archetype RC structures demonstrated
different collapse capacities at near field site compared to those of
FEMA. The reasons of differences are believed to be due to
accounting for the spectral shape effects.
Abstract: This paper describes three lumped parameters models
for the study of the dynamic behavior of a boom crane. The models
here proposed allows to evaluate the fluctuations of the load arising
from the rope and structure elasticity and from the type of the
motion command imposed by the winch. A calculation software
was developed in order to determine the actual acceleration of the
lifted mass and the dynamic overload during the lifting phase. Some
application examples are presented, with the aim of showing the
correlation between the magnitude of the stress and the type of the
employed motion command.
Abstract: An experimental study with four different types of bed
conditions was carried out to understand the effect of roughness in
open channel flow at two different Reynolds numbers. The bed
conditions include a smooth surface and three different roughness
conditions, which were generated using sand grains with a median
diameter of 2.46 mm. The three rough conditions include a surface
with distributed roughness, a surface with continuously distributed
roughness and a sand bed with a permeable interface. A commercial
two-component fibre-optic LDA system was used to conduct the
velocity measurements. The variables of interest include the mean
velocity, turbulence intensity, correlation between the streamwise and
the wall normal turbulence, Reynolds shear stress and velocity triple
products. Quadrant decomposition was used to extract the magnitude
of the Reynolds shear stress of the turbulent bursting events. The
effect of roughness was evident throughout the flow depth. The
results show that distributed roughness has the greatest roughness
effect followed by the sand bed and the continuous roughness.
Compared to the smooth bed, the streamwise turbulence intensity
reduces but the vertical turbulence intensity increases at a location
very close to the bed due to the introduction of roughness. Although
the same sand grain is used to create the three different rough bed
conditions, the difference in the turbulence intensity is an indication
that the specific geometry of the roughness has an influence on
turbulence structure.