Abstract: Optimizing the parameters in the controller plays a
vital role in the control theory and its applications. Optimizing the
PID parameters is finding out the best value from the feasible
solutions. Finding the optimal value is an optimization problem.
Inverted Pendulum is a very good platform for control engineers to
verify and apply different logics in the field of control theory. It is
necessary to find an optimization technique for the controller to tune
the values automatically in order to minimize the error within the
given bounds. In this paper, the algorithmic concepts of Harmony
search (HS) and Genetic Algorithm (GA) have been analyzed for the
given range of values. The experimental results show that HS
performs well than GA.
Abstract: This paper presents the result of an experimental
investigation regarding the use of Fe2O3 nanoparticles added to
kerosene as a working fluid, under magnetic field for Copper
Oscillating Heat pipe with inclination angle of 0°(horizontal), 15°,
30°,45°, 60°,75° and 90° (vertical). The following were examined;
measure the temperature distribution and heat transfer rate on
Oscillating Heat Pipe (OHP), with magnetic field under different
angles. Results showed that the addition of Fe2O3 nanoparticles under
magnetic field improved thermal performance of OHP especially in
75°.
Abstract: Lyophilization, also called freeze-drying, is an
important dehydration technique mainly used for pharmaceuticals.
Food industry also uses lyophilization when it is important to retain
most of the nutritional quality, taste, shape and size of dried products
and to extend their shelf life. Vacuum-Induced during freezing cycle
(VI) has been used in order to control ice nucleation and,
consequently, to reduce the time of primary drying cycle of
pharmaceuticals preserving quality properties of the final product.
This procedure has not been applied in freeze drying of foods. The
present work aims to investigate the effect of VI on the lyophilization
drying time, final moisture content, density and reconstitutional
properties of mango (Mangifera indica L.) slices (MS) and mango
pulp-maltodextrin dispersions (MPM) (30% concentration of total
solids). Control samples were run at each freezing rate without using
induced vacuum. The lyophilization endpoint was the same for all
treatments (constant difference between capacitance and Pirani
vacuum gauges). From the experimental results it can be concluded
that at the high freezing rate (0.4°C/min) reduced the overall process
time up to 30% comparing process time required for the control and
VI of the lower freeze rate (0.1°C/min) without affecting the quality
characteristics of the dried product, which yields a reduction in costs
and energy consumption for MS and MPM freeze drying. Controls
and samples treated with VI at freezing rate of 0.4°C/min in MS
showed similar results in moisture and density parameters.
Furthermore, results from MPM dispersion showed favorable values
when VI was applied because dried product with low moisture
content and low density was obtained at shorter process time
compared with the control. There were not found significant
differences between reconstitutional properties (rehydration for MS
and solubility for MPM) of freeze dried mango resulting from
controls, and VI treatments.
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.
Abstract: An analytical 4-DOF nonlinear model of a de Laval
rotor-stator system based on Energy Principles has been used
theoretically and experimentally to investigate fault symptoms in a
rotating system. The faults, namely rotor-stator-rub, crack and
unbalance are modeled as excitations on the rotor shaft. Mayes
steering function is used to simulate the breathing behaviour of the
crack. The fault analysis technique is based on waveform signal,
orbits and Fast Fourier Transform (FFT) derived from simulated and
real measured signals. Simulated and experimental results manifest
considerable mutual resemblance of elliptic-shaped orbits and FFT
for a same range of test data.
Abstract: The work reported through this paper is an
experimental work conducted on High Performance Concrete (HPC)
with super plasticizer with the aim to develop some models suitable
for prediction of compressive strength of HPC mixes. In this study,
the effect of varying proportions of fly ash (0% to 50% @ 10%
increment) on compressive strength of high performance concrete has
been evaluated. The mix designs studied were M30, M40 and M50 to
compare the effect of fly ash addition on the properties of these
concrete mixes. In all eighteen concrete mixes that have been
designed, three were conventional concretes for three grades under
discussion and fifteen were HPC with fly ash with varying
percentages of fly ash. The concrete mix designing has been done in
accordance with Indian standard recommended guidelines. All the
concrete mixes have been studied in terms of compressive strength at
7 days, 28 days, 90 days, and 365 days. All the materials used have
been kept same throughout the study to get a perfect comparison of
values of results. The models for compressive strength prediction
have been developed using Linear Regression method (LR), Artificial
Neural Network (ANN) and Leave-One-Out Validation (LOOV)
methods.
Abstract: Target of this study was the analysis of the impact of
crude glycerol on canine spermatozoa motility, morphology,
viability, and membrane integrity. Experiments were realized in vitro.
In the study, semen from 5 large dog breeds was used. They were
typical representatives of large breeds, coming from healthy rearing,
regularly vaccinated and integrated to the further breeding. Semen
collections were realized at the owners of animals and in the
veterinary clinic. Subsequently the experiments were realized at the
Department of Animal Physiology of the SUA in Nitra. The
spermatozoa motility was evaluated using CASA analyzer
(SpermVisionTM, Minitub, Germany) at the temperature 5 and 37°C
for 5 hours. In the study, 13 motility parameters were evaluated.
Generally, crude glycerol has generally negative effect on
spermatozoa motility. Morphological analysis was realized using
Hancock staining and the preparations were evaluated at
magnification 1000x using classification tables of morphologically
changed spermatozoa. Data clearly detected the highest number of
morphologically changed spermatozoa in the experimental groups
(know twisted tails, tail torso and tail coiling). For acrosome
alterations swelled acrosomes, removed acrosomes and acrosomes
with undulated membrane were detected. In this study also the effect
of crude glycerol on spermatozoa membrane integrity were analyzed.
The highest crude glycerol concentration significantly affects
spermatozoa integrity. Results of this study show that crude glycerol
has effect of spermatozoa motility, viability, and membrane integrity.
Detected changes are related to crude glycerol concentration,
temperature, as well as time of incubation.
Abstract: Operation enhancement in an air cooler depends on
rate of heat transfer, and pressure drop. In this paper for a given heat
duty, study of the effects of FPI (Fin Per Inch) and fin type (circular
and hexagonal fins) on heat transfer, and pressure drop in an air
cooler in Iran, Arvand petrochemical. A program in EES
(Engineering Equations Solver) software moreover, Aspen B-JAC
and HTFS+ softwares are used for this purpose to solve governing
equations. At first the simulated results obtained from this program is
compared to the experimental data for two cases of FPI. The effects
of FPI from 3 to 15 over heat transfer (Q) to pressure drop ratio
(Q/Δp ratio). This ratio is one of the main parameters in design, and
simulation heat exchangers. The results show that heat transfer (Q)
and pressure drop increase with increasing FPI steadily, and the Q/Δp
ratio increases to FPI=12 and then decreased gradually to FPI=15,
and Q/Δp ratio is maximum at FPI=12. The FPI value selection
between 8 and 12 obtained as a result to optimum heat transfer to
pressure drop ratio. Also by contrast, between circular and hexagonal
fins results, the Q/Δp ratio of hexagonal fins more than Q/Δp ratio of
circular fins for FPI between 8 and 12 (optimum FPI)
Abstract: Structural failure is caused mainly by damage that
often occurs on structures. Many researchers focus on to obtain very
efficient tools to detect the damage in structures in the early state. In
the past decades, a subject that has received considerable attention in
literature is the damage detection as determined by variations in the
dynamic characteristics or response of structures. The study presents
a new damage identification technique. The technique detects the
damage location for the incomplete structure system using output
data only. The method indicates the damage based on the free
vibration test data by using ‘Two Points Condensation (TPC)
technique’. This method creates a set of matrices by reducing the
structural system to two degrees of freedom systems. The current
stiffness matrices obtain from optimization the equation of motion
using the measured test data. The current stiffness matrices compare
with original (undamaged) stiffness matrices. The large percentage
changes in matrices’ coefficients lead to the location of the damage. TPC technique is applied to the experimental data of a simply
supported steel beam model structure after inducing thickness change
in one element, where two cases consider. The method detects the
damage and determines its location accurately in both cases. In
addition, the results illustrate these changes in stiffness matrix can be
a useful tool for continuous monitoring of structural safety using
ambient vibration data. Furthermore, its efficiency proves that this
technique can be used also for big structures.
Abstract: Many existing amusement parks have been operated
with assistance of a variety of information and communications
technologies to design friendly and efficient service systems for
tourists. However, these systems leave various levels of decisions to
tourists to make by themselves. This incurs pressure on tourists and
thereby bringing negative experience in their tour. This paper
proposes a smart amusement park system to offer each tourist the
GPS-based customized plan without tourists making decisions by
themselves. The proposed system consists of the mobile app
subsystem, the central subsystem, and the detecting/counting
subsystem. The mobile app subsystem interacts with the central
subsystem. The central subsystem performs the necessary computing
and database management of the proposed system. The
detecting/counting subsystem aims to detect and compute the number
of visitors to an attraction. Experimental results show that the
proposed system can not only work well, but also provide an
innovative business operating model for owners of amusement parks.
Abstract: Social Avoidance is one of the most important
problems that face a good number of disabled students. It results from
the negative attitudes of non-disabled students, teachers and others.
Some of the past research has shown that non-disabled individuals
hold negative attitudes toward persons with disabilities. The present
study aims to alleviate Social Avoidance by applying the Cognitive
Behavioral Intervention. 24 Blind students aged 19–24 (university students) were randomly
chosen we compared an experimental group (consisted of 12
students) who went through the intervention program, with a control
group (12 students also) who did not go through such intervention.
We used the Social Avoidance and Distress Scale (SADS) to assess
social anxiety and distress behavior. The author used many
techniques of cognitive behavioral intervention such as modeling,
cognitive restructuring, extension, contingency contracts, selfmonitoring,
assertiveness training, role play, encouragement and
others. Statistically, T-test was employed to test the research
hypothesis. Result showed that there is a significance difference between the
experimental group and the control group after the intervention and
also at the follow up stages of the Social Avoidance and Distress
Scale. Also for the experimental group, there is a significance
difference before the intervention and the follow up stages for the
scale. Results showed that, there is a decrease in social avoidance.
Accordingly, cognitive behavioral intervention program was
successful in decreasing social avoidance for blind students.
Abstract: The ventilated façade has great advantages when
compared to traditional façades as it reduces the air conditioning
thermal loads due to the stack effect induced by solar radiation in the
air chamber. Optimizing energy consumption by using a ventilated
façade can be used not only in newly built buildings but also it can be
implemented in existing buildings, opening the field of
implementation to energy building retrofitting works. In this sense, the following three prototypes of façade where
designed, built and further analyzed in this research: non-ventilated
façade (NVF); slightly ventilated façade (SLVF) and strongly
ventilated façade (STVF). The construction characteristics of the
three facades are based on the Spanish regulation of building
construction “Technical Building Code”. The façades have been
monitored by type-k thermocouples in a representative day of the
summer season in Madrid (Spain). Moreover, an analysis of variance
(ANOVA) with repeated measures, studying the thermal lag in the
ventilated and no-ventilated façades has been designed. Results show that STVF façade presents higher levels of thermal
inertia as the thermal lag reduces up to 17% (daily mean) compared
to the non-ventilated façade. In addition, the statistical analysis
proves that an increase of the ventilation holes size in STVF façades
can improve the thermal lag significantly (p >0.05) when compared
to the SLVF façade.
Abstract: Evolution strategy (ES) is a well-known instance of evolutionary algorithms, and there have been many studies on ES. In this paper, the author proposes an extended ES for solving fuzzy-valued optimization problems. In the proposed ES, genotype values are not real numbers but fuzzy numbers. Evolutionary processes in the ES are extended so that it can handle genotype instances with fuzzy numbers. In this study, the proposed method is experimentally applied to the evolution of neural networks with fuzzy weights and biases. Results reveal that fuzzy neural networks evolved using the proposed ES with fuzzy genotype values can model hidden target fuzzy functions even though no training data are explicitly provided. Next, the proposed method is evaluated in terms of variations in specifying fuzzy numbers as genotype values. One of the mostly adopted fuzzy numbers is a symmetric triangular one that can be specified by its lower and upper bounds (LU) or its center and width (CW). Experimental results revealed that the LU model contributed better to the fuzzy ES than the CW model, which indicates that the LU model should be adopted in future applications of the proposed method.
Abstract: Biomass treatment through densification is very suitable and helpful technology before its effective energy recovery. Densification process of biomass is significantly influenced by various technological and material variables, which are ultimately reflected on the final solid biofuels quality. The paper deals with the experimental research of the relationship between technological and material variables during densification of fast-growing trees, roundly fast-growing willows. The main goal of presented experimental research is to determine the relationship between compression pressure and raw material particle size from a final briquettes density point of view. Experimental research was realized by single-axis densification. The impact of particle size with interaction of compression pressure and stabilization time on the quality properties of briquettes was determined. These variables interaction affects the final solid biofuels (briquettes) quality. From briquettes production point of view and from densification machines constructions point of view is very important to know about mutual interaction of these variables on final briquettes quality. The experimental findings presented here are showing the importance of mentioned variables during the densification process.
Abstract: Temperature effect on the performance of a photovoltaic module is one of the main concerns that face this renewable energy, especially in hot arid region, e.g. United Arab Emirates. Overheating of the PV modules reduces the open circuit voltage and the efficiency of the modules dramatically. In this work, water-cooling is developed to enhance the performance of PV modules. Different scenarios are tested under UAE weather conditions: front, back and double cooling. A spraying system is used for the front cooling whether a direct contact water system is used for the back cooling. The experimental results are compared to non-cooling module and the performance of the PV module is determined for different situations. The experimental results show that the front cooling is more effective than the back cooling and may decrease the temperature of the PV module significantly.
Abstract: The purpose of this study is to identify human walking vertical force by using FFT power spectrum density from the experimental acceleration data of the human body. An experiment on human walking is carried out on a stationary floor especially paying attention to higher components of dynamic vertical walking force. Based on measured acceleration data of the human lumbar part, not only in-phase component with frequency of 2fw, 3fw, but also in-opposite-phase component with frequency of 0.5 fw, 1.5 fw, 2.5 fw where fw is the walking rate is observed. The vertical vibration of pedestrian bridge induced by higher components of human walking vertical force is also discussed in this paper. A full scale measurement for the existing pedestrian bridge with center span length of 33 m is carried out focusing on the resonance phenomenon due to higher components of human walking vertical force. Dynamic response characteristics excited by these vertical higher components of human walking are revealed from the dynamic design viewpoint of pedestrian bridge.
Abstract: During welding or flame cutting of metals, the
prediction of heat affected zone (HAZ) is critical. There is need to
develop a simple mathematical model to calculate the temperature
variation in HAZ and derivative analysis can be used for this purpose.
This study presents analytical solution for heat transfer through
conduction in mild steel plate. The homogeneous and nonhomogeneous
boundary conditions are single variables. The full field
analytical solutions of temperature measurement, subjected to local
heating source, are derived first by method of separation of variables
followed with the experimental visualization using infrared imaging.
Based on the present work, it is suggested that appropriate heat input
characteristics controls the temperature distribution in and around
HAZ.
Abstract: In this paper, a spatial multiple-kernel fuzzy C-means (SMKFCM) algorithm is introduced for segmentation problem. A linear combination of multiples kernels with spatial information is used in the kernel FCM (KFCM) and the updating rules for the linear coefficients of the composite kernels are derived as well. Fuzzy cmeans (FCM) based techniques have been widely used in medical image segmentation problem due to their simplicity and fast convergence. The proposed SMKFCM algorithm provides us a new flexible vehicle to fuse different pixel information in medical image segmentation and detection of MR images. To evaluate the robustness of the proposed segmentation algorithm in noisy environment, we add noise in medical brain tumor MR images and calculated the success rate and segmentation accuracy. From the experimental results it is clear that the proposed algorithm has better performance than those of other FCM based techniques for noisy medical MR images.
Abstract: Due to the interference effects, the intrinsic
aerodynamic parameters obtained from the individual component
testing are always fundamentally different than those obtained for
complete model testing. Consideration and limitation for such testing
need to be taken into account in any design work related to the
component buildup method. In this paper, the scaled model of a
straight rectangular canard of a hybrid buoyant aircraft is tested at 50
m/s in IIUM-LSWT (Low Speed Wind Tunnel). Model and its
attachment with the balance are kept rigid to have results free from
the aeroelastic distortion. Based on the velocity profile of the test
section’s floor; the height of the model is kept equal to the
corresponding boundary layer displacement. Balance measurements
provide valuable but limited information of overall aerodynamic
behavior of the model. Zero lift coefficient is obtained at -2.2o and
the corresponding drag coefficient was found to be less than that at
zero angle of attack. As a part of the validation of low fidelity tool,
plot of lift coefficient plot was verified by the experimental data and
except the value of zero lift coefficients, the overall trend has under
predicted the lift coefficient. Based on this comparative study, a
correction factor of 1.36 is proposed for lift curve slope obtained
from the panel method.
Abstract: The purpose of this research was to investigate the
creep behaviour of the heterogeneous Timber-UHPFRC beams. New
developments have been done to further improve the structural
performance, such as strengthening of the timber (glulam) beam by
bonding composite material combine with an ultra-high performance
fibre reinforced concrete (UHPFRC) internally reinforced with or
without carbon fibre reinforced polymer (CFRP) bars. However, in
the design of wooden structures, in addition to the criteria of
strengthening and stiffness, deformability due to the creep of wood,
especially in horizontal elements, is also a design criterion. Glulam,
UHPFRC and CFRP may be an interesting composite mix to respond
to the issue of creep behaviour of composite structures made of
different materials with different rheological properties. In this paper,
we describe an experimental and analytical investigation of the creep
performance of the glulam-UHPFRC-CFRP beams assembled by
bonding. The experimental investigations creep behaviour was
conducted for different environments: in- and outside under constant
loading for approximately a year. The measured results are compared
with numerical ones obtained by an analytical model. This model was
developed to predict the creep response of the glulam-UHPFRCCFRP
beams based on the creep characteristics of the individual
components. The results show that heterogeneous glulam-UHPFRC
beams provide an improvement in both the strengthening and
stiffness, and can also effectively reduce the creep deflection of
wooden beams.