Abstract: Fixed-geometry hydrodynamic journal bearings are
one of the best supporting systems for several applications of rotating
machinery. Cylindrical journal bearings present excellent loadcarrying
capacity and low manufacturing costs, but they are subjected
to the oil-film instability at high speeds. An attempt of overcoming
this instability problem has been the development of non-circular
journal bearings. This work deals with an analysis of oil-lubricated
elliptical journal bearings using the finite element method. Steadystate
and dynamic performance characteristics of elliptical bearings
are rendered by zeroth- and first-order lubrication equations obtained
through a linearized perturbation method applied on the classical
Reynolds equation. Four-node isoparametric rectangular finite
elements are employed to model the bearing thin film flow. Curves of
elliptical bearing load capacity and dynamic force coefficients are
rendered at several operating conditions. The results presented in this
work demonstrate the influence of the bearing ellipticity on its
performance at different loading conditions.
Abstract: Significant quota of Municipal Electrical Energy
consumption is related to Decentralized Air Conditioning which is
mostly provided by evaporative coolers. So the aim is to optimize
design of air conditioners to increase their efficiencies. To achieve
this goal, results of practical standardized tests for 40 evaporative
coolers in different types collected and simultaneously results for
same coolers based on one of EER (Energy Efficiency Ratio)
modeling styles are figured out. By comparing experimental results
of different coolers standardized tests with modeling results,
preciseness of used model is assessed and after comparing gained
preciseness with international standards based on EER for cooling
capacity, aeration, and also electrical energy consumption, energy
label from A (most effective) to G (less effective) is classified; finally
needed methods to optimize energy consumption and coolers’
classification are provided.
Abstract: In this paper, we introduced a gradient-based inverse
solver to obtain the missing boundary conditions based on the
readings of internal thermocouples. The results show that the method
is very sensitive to measurement errors, and becomes unstable when
small time steps are used. The artificial neural networks are shown to
be capable of capturing the whole thermal history on the run-out
table, but are not very effective in restoring the detailed behavior of
the boundary conditions. Also, they behave poorly in nonlinear cases
and where the boundary condition profile is different.
GA and PSO are more effective in finding a detailed
representation of the time-varying boundary conditions, as well as in
nonlinear cases. However, their convergence takes longer. A
variation of the basic PSO, called CRPSO, showed the best
performance among the three versions. Also, PSO proved to be
effective in handling noisy data, especially when its performance
parameters were tuned. An increase in the self-confidence parameter
was also found to be effective, as it increased the global search
capabilities of the algorithm. RPSO was the most effective variation
in dealing with noise, closely followed by CRPSO. The latter
variation is recommended for inverse heat conduction problems, as it
combines the efficiency and effectiveness required by these
problems.
Abstract: Long Distance Truck Drivers (LDTDs) have been
found to be a high risk group in the spread of HIV/AIDS globally;
perhaps, due to their high Sexual Risk Behaviours (SRBs).
Interventions for reducing SRBs in trucking population have not been
fully exploited. A quasi-experimental control group pretest-posttest
design was used to assess the efficacy of psycho-education and
behavioural skills training in reducing SRBs among LDTDs. Sixteen
drivers rivers were randomly assigned into either experimental or
control groups using balloting technique. Questionnaire was used as
an instrument for data collection. Repeated measures t-test and
independent t-test were used to test hypotheses. Intervention had
significant effect on the SRBs among LDTDs at post-test (t{7}=
6.01, p
Abstract: Co-crystal is believed to improve the solubility and
dissolution rates and thus, enhanced the bioavailability of poor water
soluble drugs particularly during the oral route of administration.
With the existing of poorly soluble drugs in pharmaceutical industry,
the screening of co-crystal formation using carbamazepine (CBZ) as
a model drug compound with dicarboxylic acids co-crystal formers
(CCF) namely fumaric (FA) and succinic (SA) acids in ethanol has
been studied. The co-crystal formations were studied by varying the
mol ratio values of CCF to CBZ to access the effect of CCF
concentration on the formation of the co-crystal. Solvent evaporation,
slurry and cooling crystallization which representing the solution
based method co-crystal screening were used. Based on the
differential scanning calorimetry (DSC) analysis, the melting point of
CBZ-SA in different ratio was in the range between 188oC-189oC.
For CBZ-FA form A and CBZ-FA form B the melting point in
different ratio were in the range of 174oC-175oC and 185oC-186oC
respectively. The product crystal from the screening was also
characterized using X-ray powder diffraction (XRPD). The XRPD
pattern profile analysis has shown that the CBZ co-crystals with FA
and SA were successfully formed for all ratios studied. The findings
revealed that CBZ-FA co-crystal were formed in two different
polymorphs. It was found that CBZ-FA form A and form B were
formed from evaporation and slurry crystallization methods
respectively. On the other hand, in cooling crystallization method,
CBZ-FA form A was formed at lower mol ratio of CCF to CBZ and
vice versa. This study disclosed that different methods and mol ratios
during the co-crystal screening can affect the outcome of co-crystal
produced such as polymorphic forms of co-crystal and thereof. Thus,
it was suggested that careful attentions is needed during the screening
since the co-crystal formation is currently one of the promising
approach to be considered in research and development for
pharmaceutical industry to improve the poorly soluble drugs.
Abstract: Gypsum (CaSO4.2H2O) is a mineral that is found in
large quantities in the Turkey and in the World. In this study, the
dissolution of this mineral in the diammonium hydrogen phosphate
solutions has been studied. The dissolution and dissolution kinetics of
gypsum in diammonium hydrogen phosphate solutions will be useful
for evaluating of solid wastes containing gypsum. Parameters such as
diammonium hydrogen phosphate concentration, temperature and
stirring speed affecting on the dissolution rate of the gypsum in
diammonium hydrogen phosphate solutions were investigated. In
experimental studies have researched effectiveness of the selected
parameters. The dissolution of gypsum were examined in two parts at
low and high temperatures. The experimental results were
successfully correlated by linear regression using Statistica program.
Dissolution curves were evaluated shrinking core models for solidfluid
systems. The activation energy was found to be 34.58 kJ/mol
and 44.45 kJ/mol for the low and the high temperatures. The
dissolution of gypsum was controlled by chemical reaction both low
temperatures and high temperatures.
Abstract: A model was constructed to predict the amount of
solar radiation that will make contact with the surface of the earth in
a given location an hour into the future. This project was supported
by the Southern Company to determine at what specific times during
a given day of the year solar panels could be relied upon to produce
energy in sufficient quantities. Due to their ability as universal
function approximators, an artificial neural network was used to
estimate the nonlinear pattern of solar radiation, which utilized
measurements of weather conditions collected at the Griffin, Georgia
weather station as inputs. A number of network configurations and
training strategies were utilized, though a multilayer perceptron with
a variety of hidden nodes trained with the resilient propagation
algorithm consistently yielded the most accurate predictions. In
addition, a modeled direct normal irradiance field and adjacent
weather station data were used to bolster prediction accuracy. In later
trials, the solar radiation field was preprocessed with a discrete
wavelet transform with the aim of removing noise from the
measurements. The current model provides predictions of solar
radiation with a mean square error of 0.0042, though ongoing efforts
are being made to further improve the model’s accuracy.
Abstract: In this paper, a direct power control (DPC)
strategies have been investigated in order to control a high
power AC/DC converter with time variable load. This converter
is composed of a three level three phase neutral point clamped
(NPC) converter as rectifier and an H-bridge four quadrant
current control converter. In the high power application,
controller not only must adjust the desire outputs but also
decrease the level of distortions which are injected to the network
from the converter. Regarding to this reason and nonlinearity
of the power electronic converter, the conventional controllers
cannot achieve appropriate responses. In this research, the
precise mathematical analysis has been employed to design the
appropriate controller in order to control the time variable
load. A DPC controller has been proposed and simulated using
Matlab/ Simulink. In order to verify the simulation result, a real
time simulator- OPAL-RT- has been employed. In this paper,
the dynamic response and stability of the high power NPC
with variable load has been investigated and compared with
conventional types using a real time simulator. The results proved
that the DPC controller is more stable and has more precise
outputs in comparison with conventional controller.
Abstract: In the past researchers have questioned the
effectiveness of ethics training in higher education. Also, there are
observations that support the view that ethical behaviour (range of
actions)/ethical decision making models used in the past make use of
vignettes to explain ethical behaviour. The understanding remains in
the perspective that these vignettes play a limited role in determining
individual intentions and not actions. Some authors have also agreed
that there are possibilities of differences in one’s intentions and
actions. This paper makes an attempt to fill those gaps by evaluating
real actions rather than intentions. In a way this study suggests the
use of an experiential methodology to explore Berlo’s model of
communication as an action along with orchestration of various
principles. To this endeavor, an attempt was made to use
conversational analysis in the pursuance of evaluating ethical
decision making behaviour among students and middle level
managers. The process was repeated six times with the set of an
average of 15 participants. Similarities have been observed in the
behaviour of students and middle level managers that calls for
understanding that both the groups of individuals have no cognizance
of their actual actions. The deliberations derived out of conversation
were taken a step forward for meta-ethical evaluations to portray a
clear picture of ethical behaviour among participants. This study
provides insights for understanding demonstrated unconscious human
behaviour which may fortuitously be termed both ethical and
unethical.
Abstract: Rural tourism is usually associated with rural
development because it has strong linkages to rural resources; but it
remains underdeveloped compared to urban tourism. This
underdevelopment of rural tourism serves as a motivation for this
study whose aim is to examine the factors affecting the perceived
satisfaction of rural tourists. The objectives of this study are: to
identify and design theories and models on rural tourism satisfaction,
and to empirically validate these models and theories through a
survey of tourists from the Malealea Lodge which is located in the
Mafeteng District, in the Mountain Kingdom of Lesotho. Data
generated by the collection of questionnaires used by this survey was
analyzed quantitatively using descriptive statistics and correlations in
SPSS after checking the validity and the reliability of the
questionnaire. The main hypothesis behind this study is the
relationship between the demographics of rural tourists, their
motivation, and their satisfaction, as supported by existing literature;
except that motivation is measured in this study according to three
dimensions: push factors, pull factors, and perceived usefulness of
ICTs in the rural tourism experience. Findings from this study
indicate that among the demographics factors, continent of origin and
marital status influence the satisfaction of rural tourists; and their
occupation affects their perceptions on the use of ICTs in rural
tourism. Moreover, only pull factors were found to influence the
satisfaction of rural tourists.
Abstract: The arm length, hand length, hand breadth and middle
finger length of 1540 right-handed industrial workers of Haryana
state was used to assess the relationship between the upper limb
dimensions and stature. Initially, the data were analyzed using basic
univariate analysis and independent t-tests; then simple and multiple
linear regression models were used to estimate stature using SPSS
(version 17). There was a positive correlation between upper limb
measurements (hand length, hand breadth, arm length and middle
finger length) and stature (p < 0.01), which was highest for hand
length. The accuracy of stature prediction ranged from ± 54.897 mm
to ± 58.307 mm. The use of multiple regression equations gave better
results than simple regression equations. This study provides new
forensic standards for stature estimation from the upper limb
measurements of male industrial workers of Haryana (India). The
results of this research indicate that stature can be determined using
hand dimensions with accuracy, when only upper limb is available
due to any reasons likewise explosions, train/plane crashes, mutilated
bodies, etc. The regression formula derived in this study will be
useful for anatomists, archaeologists, anthropologists, design
engineers and forensic scientists for fairly prediction of stature using
regression equations.
Abstract: The main purpose of this paper is to determine the
applicability of the constitutional social rights in the so-called
horizontal relations, i.e. the relations between private entities.
Nowadays the constitutional rights are more and more often violated
by private entities and not only by the state. The private entities
interfere with the privacy of individuals, limit their freedom of
expression or disturb their peaceful gatherings. International
corporations subordinate individuals in a way which may limit their
constitutional rights. These new realities determine the new role of
the constitution in protecting human rights.
The paper will aim at answering two important questions. Firstly,
are the private entities obliged to respect the constitutional social
rights of other private entities and can they be liable for violation of
these rights? Secondly, how the constitutional social rights can
receive horizontal effect? Answers to these questions will have a
significant meaning for the popularisation of the practice of applying
the Constitution among the citizens as well as for the courts which
settle disputes between them.
Abstract: R.C.C. buildings with dual structural system
consisting of shear walls (or braces) and moment resisting frames
have been widely used to resist lateral forces during earthquakes. The
dual systems are designed to resist the total design lateral force in
proportion to their lateral stiffness. The response of combination of
braces and shear walls has not yet been studied. The combination
may prove to be more effective to resist lateral forces during
earthquakes. This concept has been applied to regular R.C.C.
buildings provided with shear walls, braces and their combinations.
Abstract: In this paper, the exergy analysis of vapor absorption
refrigeration system using LiBr-H2O as working fluid is carried out
with the modified Gouy-Stodola approach rather than the classical
Gouy-Stodola equation and effect of varying input parameters is also
studied on the performance of the system. As the modified approach
uses the concept of effective temperature, the mathematical
expressions for effective temperature have been formulated and
calculated for each component of the system. Various constraints and
equations are used to develop program in EES to solve these
equations. The main aim of this analysis is to determine the
performance of the system and the components having major
irreversible loss. Results show that exergy destruction rate is
considerable in absorber and generator followed by evaporator and
condenser. There is an increase in exergy destruction in generator,
absorber and condenser and decrease in the evaporator by the
modified approach as compared to the conventional approach. The
value of exergy determined by the modified Gouy-Stodola equation
deviates maximum i.e. 26% in the generator as compared to the
exergy calculated by the classical Gouy-Stodola method.
Abstract: The adaptation of social networking sites within
higher education has garnered significant interest in the recent years
with numerous researches considering it as a possible shift from the
traditional classroom based learning paradigm. Notwithstanding this
increase in research and conducted studies however, the adaption of
SNS based modules have failed to proliferate within Universities.
This paper commences its contribution by analyzing the various
models and theories proposed in literature and amalgamate together
various effective aspects for the inclusion of social technology within
e-Learning. A three phased framework is further proposed which
details the necessary considerations for the successful adaptation of
SNS in enhancing the students learning experience. This proposal
outlines the theoretical foundations which will be analyzed in
practical implementation across international university campuses.
Abstract: Wireless Sensor Networks (WSNs) have wide variety
of applications and provide limitless future potentials. Nodes in
WSNs are prone to failure due to energy depletion, hardware failure,
communication link errors, malicious attacks, and so on. Therefore,
fault tolerance is one of the critical issues in WSNs. We study how
fault tolerance is addressed in different applications of WSNs. Fault
tolerant routing is a critical task for sensor networks operating in
dynamic environments. Many routing, power management, and data
dissemination protocols have been specifically designed for WSNs
where energy awareness is an essential design issue. The focus,
however, has been given to the routing protocols which might differ
depending on the application and network architecture.
Abstract: Essential oils have a significant antimicrobial activity.
These oils can successfully replace the antibiotics. So, the
microorganisms show their inefficiencies resistant for the antibiotics.
For this reason, we study the physicochemical analysis and
antimicrobial activity of the essential oil of Daucus carota. The
extraction is done by steam distillation of water which brought us a
very significant return of 4.65%. The analysis of the essential oil is
performed by GC / MS and has allowed us to identify 32 compounds
in the oil of D. carota flowering tops of Bouira. Three of which are in
the majority are the α-Pinene (22.3%), the carotol (21.7%) and the
limonene (15.8%).
Abstract: Cloud computing is a new technology in industry and
academia. The technology has grown and matured in last half decade
and proven their significant role in changing environment of IT
infrastructure where cloud services and resources are offered over the
network. Cloud technology enables users to use services and
resources without being concerned about the technical implications of
technology. There are substantial research work has been performed
for the usage of cloud computing in educational institutes and
majority of them provides cloud services over high-end blade servers
or other high-end CPUs. However, this paper proposes a new stack
called “CiCKAStack” which provide cloud services over unutilized
computing resources, named as commodity computers.
“CiCKAStack” provides IaaS and PaaS using underlying commodity
computers. This will not only increasing the utilization of existing
computing resources but also provide organize file system, on
demand computing resource and design and development
environment.
Abstract: International and domestic environmental law has
evolved quite rapidly in the last few decades. At the international
level the Stockholm and Rio Declarations paved the way for a broad
based consensus of the international community on environmental
issues and principles. At the Domestic level also many states have
incorporated environmental protection in their constitutions and even
more states are doing the same at least in their domestic legislations.
In this process of evolution environmental law has unleashed a
number of novel principles such as; the participatory principle, the
polluter pays principle, the precautionary principle, the intergenerational
and intra-generational principles, the prevention
principle, the sustainable development principle and so on.
Abstract: Flash Floods, together with landslides, are a common
natural threat for people living in mountainous regions and foothills.
One way to deal with this constant menace is the use of Early
Warning Systems, which have become a very important mitigation
strategy for natural disasters.
In this work we present our proposal for a pilot Flash Flood Early
Warning System for Santiago, Chile, the first stage of a more
ambitious project that in a future stage shall also include early
warning of landslides.
To give a context for our approach, we first analyze three existing
Flash Flood Early Warning Systems, focusing on their general
architectures. We then present our proposed system, with main focus
on the decision support system, a system that integrates empirical
models and fuzzy expert systems to achieve reliable risk estimations.