Abstract: The objective of this study is to propose a statistical
modeling method which enables simultaneous term structure
estimation of the risk-free interest rate, hazard and loss given default,
incorporating the characteristics of the bond issuing company such as
credit rating and financial information. A reduced form model is used
for this purpose. Statistical techniques such as spline estimation and
Bayesian information criterion are employed for parameter estimation
and model selection. An empirical analysis is conducted using the
information on the Japanese bond market data. Results of the
empirical analysis confirm the usefulness of the proposed method.
Abstract: The rising price of fossil fuels, government incentives
and growing public aware-ness for the need to implement sustainable
energy supplies has resulted in a large in-crease in solar panel
installations across the country. For many sites the most eco-nomical
solar panel installation uses existing, southerly facing rooftops.
Adding solar panels to an existing roof typically means increased
loads that must be borne by the building-s structural elements. The
structural design professional is responsible for ensuring a new solar
panel installation is properly supported by an existing structure and
configured to maximize energy generation.
Abstract: Contact centres have been exemplars of scientific management in the discipline of operations management for more than a decade now. With the movement of industries from a resource based economy to knowledge based economy businesses have started to realize the customer eccentricity being the key to sustainability amidst high velocity of the market. However, as technologies have converged and advanced, so have the contact centres. Contact Centres have redirected the supply chains and the concept of retailing is highly diminished due to over exaggeration of cost reduction strategies. In conditions of high environmental velocity together with services featuring considerable information intensity contact centres will require up to date and enlightened agents to satisfy the demands placed upon them by those requesting their services. In this paper we examine salient factors such as Power Distance, Knowledge structures and the dynamics of job specialisation and enlargement to suggest critical success factors in the domain of contact centres.
Abstract: Single crystals of Magnesium alloys such as pure Mg,
Mg-1Zn-0.5Y, Mg-0.1Y, and Mg-0.1Ce alloys were successfully
fabricated in this study by employing the modified Bridgman method.
To determine the exact orientation of crystals, pole figure
measurement using X-ray diffraction were carried out on each single
crystal. Hardness and compression tests were conducted followed by
subsequent recrysatllization annealing. Recrystallization kinetics of
Mg alloy single crystals has been investigated. Fabricated single
crystals were cut into rectangular shaped specimen and solution
treated at 400oC for 24 hrs, and then deformed in compression mode
by 30% reduction. Annealing treatment for recrystallization has been
conducted on these cold-rolled plates at temperatures of 300oC for
various times from 1 to 20 mins. The microstructure observation and
hardness measurement conducted on the recrystallized specimens
revealed that static recrystallization of ternary alloy single crystal was
very slow, while recrystallization behavior of binary alloy single
crystals appeared to be very fast.
Abstract: In this paper the application of rule mining in order to
review the effective factors on supplier selection is reviewed in the
following three sections 1) criteria selecting and information
gathering 2) performing association rule mining 3) validation and
constituting rule base. Afterwards a few of applications of rule base
is explained. Then, a numerical example is presented and analyzed
by Clementine software. Some of extracted rules as well as the
results are presented at the end.
Abstract: Flash memory has become an important storage device
in many embedded systems because of its high performance, low
power consumption and shock resistance. Multi-level cell (MLC) is
developed as an effective solution for reducing the cost and increasing
the storage density in recent years. However, most of flash file system
cannot handle the error correction sufficiently. To correct more errors
for MLC, we implement Reed-Solomon (RS) code to YAFFS, what is
widely used for flash-based file system. RS code has longer computing
time but the correcting ability is much higher than that of Hamming
code.
Abstract: As data to be stored in storage subsystems
tremendously increases, data protection techniques have become more
important than ever, to provide data availability and reliability. In this
paper, we present the file system-based data protection (WOWSnap)
that has been implemented using WORM (Write-Once-Read-Many)
scheme. In the WOWSnap, once WORM files have been created, only
the privileged read requests to them are allowed to protect data against
any intentional/accidental intrusions. Furthermore, all WORM files
are related to their protection cycle that is a time period during which
WORM files should securely be protected. Once their protection cycle
is expired, the WORM files are automatically moved to the
general-purpose data section without any user interference. This
prevents the WORM data section from being consumed by
unnecessary files. We evaluated the performance of WOWSnap on
Linux cluster.
Abstract: This paper aims at numerically analysing the effect
of an active flow control (AFC) by a vortex generator jet (VGJ)
submerged in a boundary layer via Chimera Grids and Detached-
Eddy Simulation (DES). The performance of DES results are
judged against Reynolds-Averaged Navier-Stokes (RANS) and
compared with the experiments that showed an unsteady vortex
motion downstream of VGJ. Experimental results showed that
the mechanism of embedding logitudinal vortex structure in the
main stream flow is quite effective in increasing the near wall
momentum of separated aircraft wing. In order to simulate such
a flow configuration together with the VGJ, an efficient numerical
approach is required. This requirement is fulfilled by performing
the DES simulation over the flat plate using the DLR TAU Code.
The DES predictions identify the vortex region via smooth hybrid
length scale and predict the unsteady vortex motion observed in
the experiments. The DES results also showed that the sufficient
grid refinement in the vortex region resolves the turbulent scales
downstream of the VGJ, the spatial vortex core postion and nondimensional
momentum coefficient RVx .
Abstract: Genetic Algorithm has been used to solve wide range of optimization problems. Some researches conduct on applying Genetic Algorithm to analog circuit design automation. These researches show a better performance due to the nature of Genetic Algorithm. In this paper a modified Genetic Algorithm is applied for analog circuit design automation. The modifications are made to the topology of the circuit. These modifications will lead to a more computationally efficient algorithm.
Abstract: The aerodynamic stall control of a baseline 13-percent
thick NASA GA(W)-2 airfoil using a synthetic jet actuator (SJA) is
presented in this paper. Unsteady Reynolds-averaged Navier-Stokes
equations are solved on a hybrid grid using a commercial software to
simulate the effects of a synthetic jet actuator located at 13% of the
chord from the leading edge at a Reynolds number Re = 2.1x106 and
incidence angles from 16 to 22 degrees. The experimental data for the
pressure distribution at Re = 3x106 and aerodynamic coefficients at
Re = 2.1x106 (angle of attack varied from -16 to 22 degrees) without
SJA is compared with the computational fluid dynamic (CFD)
simulation as a baseline validation. A good agreement of the CFD
simulations is obtained for aerodynamic coefficients and pressure
distribution.
A working SJA has been integrated with the baseline airfoil and
initial focus is on the aerodynamic stall control at angles of attack
from 16 to 22 degrees. The results show a noticeable improvement in
the aerodynamic performance with increase in lift and decrease in
drag at these post stall regimes.
Abstract: Purpose: To develop a method for automatic segmentation of adipose and muscular tissue in thighs from magnetic resonance images. Materials and methods: Thirty obese women were scanned on a Siemens Impact Expert 1T resonance machine. 1500 images were finally used in the tests. The developed segmentation method is a recursive and multilevel process that makes use of several concepts such as shaped histograms, adaptative thresholding and connectivity. The segmentation process was implemented in Matlab and operates without the need of any user interaction. The whole set of images were segmented with the developed method. An expert radiologist segmented the same set of images following a manual procedure with the aid of the SliceOmatic software (Tomovision). These constituted our 'goal standard'. Results: The number of coincidental pixels of the automatic and manual segmentation procedures was measured. The average results were above 90 % of success in most of the images. Conclusions: The proposed approach allows effective automatic segmentation of MRIs from thighs, comparable to expert manual performance.
Abstract: Providing authentication for the messages exchanged
between group members in addition to confidentiality is an important
issue in Secure Group communication. We develop a protocol for
Secure Authentic Communication where we address authentication
for the group communication scheme proposed by Blundo et al.
which only provides confidentiality. Authentication scheme used is a
multiparty authentication scheme which allows all the users in the
system to send and receive messages simultaneously. Our scheme is
secure against colluding malicious parties numbering fewer than k.
Abstract: The motion planning technique described in this paper has been developed to eliminate or reduce the residual vibrations of belt-driven rotary platforms, while maintaining unchanged the motion time and the total angular displacement of the platform. The proposed approach is based on a suitable choice of the motion command given to the servomotor that drives the mechanical device; this command is defined by some numerical coefficients which determine the shape of the displacement, velocity and acceleration profiles. Using a numerical optimization technique, these coefficients can be changed without altering the continuity conditions imposed on the displacement and its time derivatives at the initial and final time instants. The proposed technique can be easily and quickly implemented on an actual device, since it requires only a simple modification of the motion command profile mapped in the memory of the electronic motion controller.
Abstract: The aim of this study was to test whether the Attention
Networks Test (ANT) showed temporal decrements in performance.
Vigilance tasks typically show such decrements, which may reflect
impairments in executive control resulting from cognitive fatigue.
The ANT assesses executive control, as well as alerting and
orienting. Thus, it was hypothesized that ANT executive control
would deteriorate over time. Manipulations including task condition
(trial composition) and masking were included in the experimental
design in an attempt to increase performance decrements. However,
results showed that there is no temporal decrement on the ANT. The
roles of task demands, cognitive fatigue and participant motivation in
producing this result are discussed. The ANT may not be an effective
tool for investigating temporal decrement in attention.
Abstract: Agropyron cristatum L. Gaertn. is a native grass of
semiarid region in Iran which is quit resistant to cool and drought
climate and withstand heavy grazing. This species has close
phylogenetic relationship with Triticum and Hordeum. In this
research, the effect of seven different concentrations of growth
regulator 2,4-D on callus production and somatic embryogenesis of
A. cristatum was investigated on Murashige and Skoog medium. The
results showed that the rate of callus, embryo and neomorph were
highest in 1 mg L-1 2,4-D. Callus production was increased in 1 mg
L-1 2,4-D but dramatically decreased at 5.5 and 9 mg L-1 2,4-D. The
somatic embryos were observed at 1 and 4 mg L-1 2,4-D but matured
embryos and plantlet were only occurred at 1 mg L-1 2,4-D. There
were significant differences between 1 mg L-1 2,4-D and other
treatments for producing globular and torpedo embryos, plantlet,
rooted callus and number of roots (p
Abstract: It is well known that metallic particles reduce the
reliability of Gas-Insulated Substation (GIS) equipments by initiating
partial discharge (PDs) that can lead to breakdown and complete
failure of GIS. This paper investigates the characteristics of PDs
caused by metallic particle adhering to the solid spacer. The PD
detection and measurement were carried out by using IEC 60270
method with particles of different sizes and at different positions on
the spacer surface. The results show that a particle of certain size at
certain position possesses a unique PD characteristic as compared to
those caused by particles of different sizes and/or at different
positions. Therefore PD characteristics may be useful for the particle
size and position identification.
Abstract: This study employs the use of the fourth order
Numerov scheme to determine the eigenstates and eigenvalues of
particles, electrons in particular, in single and double delta function
potentials. For the single delta potential, it is found that the
eigenstates could only be attained by using specific potential depths.
The depth of the delta potential well has a value that varies depending
on the delta strength. These depths are used for each well on the
double delta function potential and the eigenvalues are determined.
There are two bound states found in the computation, one with a
symmetric eigenstate and another one which is antisymmetric.
Abstract: Today technological process makes possible surface
control of producing parts which is needful for product quality
guarantee. Geometrical structure of part surface includes form,
proportion, accuracy to shape, accuracy to size, alignment and
surface topography (roughness, waviness, etc.). All these parameters
are dependence at technology, production machine parameters,
material properties, but also at human, etc. Every parameters
approves at total part accuracy, it is means at accuracy to shape. One
of the most important accuracy to shape element is roundness. This
paper will be deals by comparison of roughness deviations at
coordination measuring machines and at special single purpose
machines. Will describing measuring by discreet method
(discontinuous) and scanning method (continuous) at coordination
measuring machines and confrontation with reference method using
at single purpose machines.
Abstract: Bay leaves have been shown to improve insulin
function in vitro but the effects on people have not been determined.
The objective of this study was to determine if bay leaves may be
important in the prevention and/or alleviation of type 1 diabetes.
Methods: Fifty five people with type 1 diabetes were divided into
two groups, 45 given capsules containing 3 g of bay leaves per day
for 30 days and 10 given a placebo capsules. Results All the patients
consumed bay leaves shows reduced serum glucose with significant
decreases 27% after 30 d. Total cholesterol decreased, 21 %, after 30
days with larger decreases in low density lipoprotein (LDL) 24%.
High density lipoprotein (HDL) increased 20% and Triglycerides
also decreased 26%. There were no significant changes in the
placebo group. Conclusion, this study demonstrates that consumption
of bay leaves, 3 g/d for 30 days, decreases risk factors for diabetes
and cardiovascular diseases and suggests that bay leaves may be
beneficial for people with type 1 diabetes.
Abstract: The Pads have unique values of thermophysical
properties (THP) having important contribution over heat transfer
into the PCB structure.
Materials with high thermal diffusivity (TD) rapidly adjust their
temperature to that of their surroundings, because the HT is quick in
compare to their volumetric heat capacity (VHC).
In the paper is presenting the diffusivity tests (ASTM E1461 flash
method) for PCBs with different core materials. In the experiments,
the multilayer structure of PCBA was taken into consideration, an
equivalent property referring to each of experimental structure be
practically measured.
Concerning to entire structure, the THP emphasize the major
contribution of substrate in establishing of reflow soldering process
(RSP) heat transfer necessities. This conclusion offer practical
solution for heat transfer time constant calculation as function of
thickness and substrate material diffusivity with an acceptable error
estimation.