Abstract: Addition of milli or micro sized particles to the heat
transfer fluid is one of the many techniques employed for improving
heat transfer rate. Though this looks simple, this method has
practical problems such as high pressure loss, clogging and erosion
of the material of construction. These problems can be overcome by
using nanofluids, which is a dispersion of nanosized particles in a
base fluid. Nanoparticles increase the thermal conductivity of the
base fluid manifold which in turn increases the heat transfer rate.
Nanoparticles also increase the viscosity of the basefluid resulting in
higher pressure drop for the nanofluid compared to the base fluid. So
it is imperative that the Reynolds number (Re) and the volume
fraction have to be optimum for better thermal hydraulic
effectiveness. In this work, the heat transfer enhancement using
aluminium oxide nanofluid using low and high volume fraction
nanofluids in turbulent pipe flow with constant wall temperature has
been studied by computational fluid dynamic modeling of the
nanofluid flow adopting the single phase approach. Nanofluid, up till
a volume fraction of 1% is found to be an effective heat transfer
enhancement technique. The Nusselt number (Nu) and friction factor
predictions for the low volume fractions (i.e. 0.02%, 0.1 and 0.5%)
agree very well with the experimental values of Sundar and Sharma
(2010). While, predictions for the high volume fraction nanofluids
(i.e. 1%, 4% and 6%) are found to have reasonable agreement with
both experimental and numerical results available in the literature.
So the computationally inexpensive single phase approach can be
used for heat transfer and pressure drop prediction of new nanofluids.
Abstract: This paper aims to (1) analyze the profiles of
transgressors (detected evaders); (2) examine reason(s) that triggered a
tax audit, causes of tax evasion, audit timeframe and tax penalty
charged; and (3) to assess if tax auditors followed the guidelines as
stated in the 'Tax Audit Framework' when conducting tax audits. In
2011, the Inland Revenue Board Malaysia (IRBM) had audited and
finalized 557 company cases. With official permission, data of all the
557 cases were obtained from the IRBM. Of these, a total of 421 cases
with complete information were analyzed. About 58.1% was small and
medium corporations and from the construction industry (32.8%). The
selection for tax audit was based on risk analysis (66.8%), information
from third party (11.1%), and firm with low profitability or fluctuating
profit pattern (7.8%). The three persistent causes of tax evasion by
firms were over claimed expenses (46.8%), fraudulent reporting of
income (38.5%) and overstating purchases (10.5%). These findings
are consistent with past literature. Results showed that tax auditors
took six to 18 months to close audit cases. More than half of tax
evaders were fined 45% on additional tax raised during audit for the
first offence. The study found tax auditors did follow the guidelines in
the 'Tax Audit Framework' in audit selection, settlement and penalty
imposition.
Abstract: This paper explores the effectiveness of machine
learning techniques in detecting firms that issue fraudulent financial
statements (FFS) and deals with the identification of factors
associated to FFS. To this end, a number of experiments have been
conducted using representative learning algorithms, which were
trained using a data set of 164 fraud and non-fraud Greek firms in the
recent period 2001-2002. The decision of which particular method to
choose is a complicated problem. A good alternative to choosing
only one method is to create a hybrid forecasting system
incorporating a number of possible solution methods as components
(an ensemble of classifiers). For this purpose, we have implemented
a hybrid decision support system that combines the representative
algorithms using a stacking variant methodology and achieves better
performance than any examined simple and ensemble method. To
sum up, this study indicates that the investigation of financial
information can be used in the identification of FFS and underline the
importance of financial ratios.
Abstract: In this competitive age, one of the key tools of most successful organizations is knowledge management. Today some organizations measure their current knowledge and use it as an indicator for rating the organization on their reports. Noting that the universities and colleges of medical science have a great role in public health of societies, their access to newest scientific research and the establishment of organizational knowledge management systems is very important. In order to explore the Application of Knowledge Management Factors, a national study was undertaken. The main purpose of this study was to find the rate of the application of knowledge management factors and some ways to establish more application of knowledge management system in Esfahan University-s Medical College (EUMC). Esfahan is the second largest city after Tehran, the capital city of Iran, and the EUMC is the biggest medical college in Esfahan. To rate the application of knowledge management, this study uses a quantitative research methodology based on Probst, Raub and Romhardt model of knowledge management. A group of 267 faculty members and staff of the EUMC were asked via questionnaire. Finding showed that the rate of the application of knowledge management factors in EUMC have been lower than average. As a result, an interview with ten faculty members conducted to find the guidelines to establish more applications of knowledge management system in EUMC.
Abstract: The correct design of the regulators structure requires complete prediction of the ultimate dimensions of the scour hole profile formed downstream the solid apron. The study of scour downstream regulator is studied either on solid aprons by means of velocity distribution or on movable bed by studying the topography of the scour hole formed in the downstream. In this paper, a new technique was developed to study the scour hole downstream regulators on movable beds. The study was divided into two categories; the first is to find out the sum of the lengths of rigid apron behind the gates in addition to the length of scour hole formed downstream, while the second is to find the minimum length of rigid apron behind the gates to prevent erosion downstream it. The study covers free and submerged hydraulic jump conditions in both symmetrical and asymmetrical under-gated regulations. From the comparison between the studied categories, we found that the minimum length of rigid apron to prevent scour (Ls) is greater than the sum of the lengths of rigid apron and that of scour hole formed behind it (L+Xs). On the other hand, the scour hole dimensions in case of submerged hydraulic jump is always greater than free one, also the scour hole dimensions in asymmetrical operation is greater than symmetrical one.
Abstract: This paper analytically investigates the 3D flow
pattern at the confluences of two rectangular channels having 900
angles using Navier-Stokes equations based on Reynolds Stress
Turbulence Model (RSM). The equations are solved by the Finite-
Volume Method (FVM) and the flow is analyzed in terms of steadystate
(single-phased) conditions. The Shumate experimental findings
were used to test the validity of data. Comparison of the simulation
model with the experimental ones indicated a close proximity
between the flow patterns of the two sets. Effects of the discharge
ratio on separation zone dimensions created in the main-channel
downstream of the confluence indicated an inverse relation, where a
decrease in discharge ratio, will entail an increase in the length and
width of the separation zone. The study also found the model as a
powerful analytical tool in the feasibility study of hydraulic
engineering projects.
Abstract: Secure electronic payment system is presented in this
paper. This electronic payment system is to be secure for clients such
as customers and shop owners. The security architecture of the
system is designed by RC5 encryption / decryption algorithm. This
eliminates the fraud that occurs today with stolen credit card
numbers. The symmetric key cryptosystem RC5 can protect
conventional transaction data such as account numbers, amount and
other information. This process can be done electronically using RC5
encryption / decryption program written by Microsoft Visual Basic
6.0. There is no danger of any data sent within the system being
intercepted, and replaced. The alternative is to use the existing
network, and to encrypt all data transmissions. The system with
encryption is acceptably secure, but that the level of encryption has
to be stepped up, as computing power increases. Results In order to
be secure the system the communication between modules is
encrypted using symmetric key cryptosystem RC5. The system will
use simple user name, password, user ID, user type and cipher
authentication mechanism for identification, when the user first
enters the system. It is the most common method of authentication in
most computer system.
Abstract: Iron oxide nanoparticle was synthesized by reactive-precipitation method followed by high speed centrifuge and phase transfer in order to stabilized nanoparticles in the solvent. Particle size of SPIO was 8.2 nm by SEM, and the hydraulic radius was 17.5 nm by dynamic light scattering method. Coercivity and saturated magnetism were determined by VSM (vibrating sample magnetometer), coercivity of nanoparticle was lower than 10 Hc, and the saturated magnetism was higher than 65 emu/g. Stabilized SPIO was then transferred to aqueous phase by reacted with excess amount of poly (ethylene glycol) (PEG) silane. After filtration and dialysis, the SPIO T2 contrast agent was ready to use. The hydraulic radius of final product was about 70~100 nm, the relaxation rates R2 (1/T2) measured by magnetic resonance imaging (MRI) was larger than 200(sec-1).
Abstract: This paper looks into detailed investigation of
thermal-hydraulic characteristics of the flow field in a fuel rod
model, especially near the spacer. The area investigate represents a
source of information on the velocity flow field, vortex, and on the
amount of heat transfer into the coolant all of which are critical for
the design and improvement of the fuel rod in nuclear power plants.
The flow field investigation uses three-dimensional Computational
Fluid Dynamics (CFD) with the Reynolds stresses turbulence model
(RSM). The fuel rod model incorporates a vertical annular channel
where three different shapes of spacers are used; each spacer shape is
addressed individually. These spacers are mutually compared in
consideration of heat transfer capabilities between the coolant and
the fuel rod model. The results are complemented with the calculated
heat transfer coefficient in the location of the spacer and along the
stainless-steel pipe.
Abstract: Subgrade moisture content varies with environmental and soil conditions and has significant influence on pavement performance. Therefore, it is important to establish realistic estimates of expected subgrade moisture contents to account for the effects of this variable on predicted pavement performance during the design stage properly. The initial boundary soil suction profile for a given pavement is a critical factor in determining expected moisture variations in the subgrade for given pavement and climatic and soil conditions. Several numerical models have been developed for predicting water and solute transport in saturated and unsaturated subgrade soils. Soil hydraulic properties are required for quantitatively describing water and chemical transport processes in soils by the numerical models. The required hydraulic properties are hydraulic conductivity, water diffusivity, and specific water capacity. The objective of this paper was to determine isothermal moisture profiles in a soil fill and predict the soil moisture movement above the ground water table using a simple one-dimensional finite difference model.
Abstract: This paper describes the design considerations of an
experimental setup for research and exploring the drives of batteryfed
electric vehicles. Effective setup composition and its components
are discussed. With experimental setup described in this paper,
durability and functional tests can be procured to the customers.
Multiple experiments are performed in the form of steady-state
system exploring, acceleration programs, multi-step tests (speed
control, torque control), load collectives or close-to-reality driving
tests (driving simulation). Main focus of the functional testing is on
the measurements of power and energy efficiency and investigations
in driving simulation mode, which are used for application purposes.
In order to enable the examination of the drive trains beyond
standard modes of operation, different other parameters can be
studied also.
Abstract: Total liquid ventilation can support gas exchange in animal models of lung injury. Clinical application awaits further technical improvements and performance verification. Our aim was to develop a liquid ventilator, able to deliver accurate tidal volumes, and a computerized system for measuring lung mechanics. The computer-assisted, piston-driven respirator controlled ventilatory parameters that were displayed and modified on a real-time basis. Pressure and temperature transducers along with a lineal displacement controller provided the necessary signals to calculate lung mechanics. Ten newborn lambs (
Abstract: Many applications require surface modification and
micro-structuring of polymers. For these purposes is mainly used
ultraviolet (UV) radiation from excimer lamps or excimer lasers.
However, these sources have a decided disadvantage - degrading the
polymer deep inside due to relatively big radiation penetration depth
which may exceed 100 μm. In contrast, extreme ultraviolet (EUV)
radiation is absorbed in a layer approximately 100 nm thick only. In
this work, the radiation from a discharge-plasma EUV source (with
wavelength 46.9 nm) based on a capillary discharge driver is focused
with a spherical Si/Sc multilayer mirror for surface modification of
PMMA sample or thin gold layer (thickness about 40 nm). It was
found that the focused EUV laser beam is capable by one shot to
ablate PMMA or layer of gold, even if the focus is significantly
influenced by astigmatism.
Abstract: A robust wheel slip controller for electric vehicles is
introduced. The proposed wheel slip controller exploits the dynamics
of electric traction drives and conventional hydraulic brakes for
achieving maximum energy efficiency and driving safety. Due to
the control of single wheel traction motors in combination with a
hydraulic braking system, it can be shown, that energy recuperation
and vehicle stability control can be realized simultaneously. The
derivation of a sliding mode wheel slip controller accessing two
drivetrain actuators is outlined and a comparison to a conventionally
braked vehicle is shown by means of simulation.
Abstract: Removal of Methylene Blue (MB) from aqueous
solution by adsorbing it on Gypsum was investigated by batch
method. The studies were conducted at 25°C and included the effects
of pH and initial concentration of Methylene Blue. The adsorption
data was analyzed by using the Langmuir, Freundlich and Tempkin
isotherm models. The maximum monolayer adsorption capacity was
found to be 36 mg of the dye per gram of gypsum. The data were
also analyzed in terms of their kinetic behavior and was found to
obey the pseudo second order equation.
Abstract: We focus on the excitation and propagation properties
of surface plasmon polariton (SPP). We have developed a SPP
excitation device in combination with a grating structures fabricated
by using the scanning probe lithography. Perturbation approach was
used to investigate the coupling properties of SPP with a spatial
harmonic wave supported by a metallic grating. A phase shift grating
SPP coupler has been fabricated and the optical property was
evaluated by the Fraunhofer diffraction formula. We have been
experimentally confirmed the induced stop band by diffraction
measurement. We have also observed the wavenumber shift of the
resonance condition of SPP owing to effect of a phase shift.
Abstract: The objective of this research was to study the themes
of alcoholic beverage advertisements in Thailand after the enactment
of the 2008 Alcoholic Beverage Control Act. Data was collected
through textual analysis of 35 television and cinema advertisements
for alcoholic beverage products broadcast in Thailand. Nine themes
were identified, seven of which were themes that had previously been
used before the new law (i.e. power, competition, friendship,
Thainess, success, romance and safety) and two of which were new
themes (volunteerism and conservation) that were introduced as a
form of adaptation and negotiation in response to the new law.
Abstract: Total liquid ventilation can support gas exchange in animal models of lung injury. Clinical application awaits further technical improvements and performance verification. Our aim was to develop a liquid ventilator, able to deliver accurate tidal volumes, and a computerized system for measuring lung mechanics. The computer-assisted, piston-driven respirator controlled ventilatory parameters that were displayed and modified on a real-time basis. Pressure and temperature transducers along with a lineal displacement controller provided the necessary signals to calculate lung mechanics. Ten newborn lambs (
Abstract: From the beginning of creation, human being has ever
fought against the ecosystem by changes has made in environment.
The most environmental changes on the nature have been done after
starting the concentrated life in the same region. Dams are one of the
most important buildings in water resources and transferring. These
buildings have been made from old times without access to
hydrological, hydraulically, hydro mechanical information. Dams
have positive and negative effects on environment. Constructing a
dam relatively causes equal ecological consequences. According to
different criteria, environmental effects of dams can lead short term
and long term damages. These effects may influence on the situation
and treatment of meteorology, biology, culture, ancient works, etc
and severely causes to change and complicate it. So considering
importance of positive effects of dam construction, it is necessary to
minimize negative environmental effects of dams to achieve a stable
development. In this article the considered effects and their solutions
in influencing on assessment of destructive environmental effects of
dams construction have been surveyed and presented.
Abstract: Cavitation, usually known as a destructive
phenomenon, involves turbulent unsteady two-phase flow. Having
such features, cavitating flows have been turned to a challenging
topic in numerical studies and many researches are being done for
better understanding of bubbly flows and proposing solutions to
reduce its consequent destructive effects. Aeration may be regarded
as an effective protection against cavitation erosion in many
hydraulic structures, like gated tunnels. The paper concerns
numerical simulation of flow in discharge gated tunnel of a dam
using ing RNG k -ε model coupled with the volume of fluid (VOF)
method and the zone which is susceptible of cavitation inception in
the tunnel is predicted. In the second step, a vent is considered in the
mentioned zone for aeration and the numerical simulation is done
again to study the effects of aeration. The results show that aeration
is an impressively useful method to exclude cavitation in mentioned
tunnels.