Abstract: In this paper we present a classification of the various technologies applied for the solution of the portfolio selection problem according to the discipline and the methodological framework followed. We provide a concise presentation of the emerged categories and we are trying to identify which methods considered obsolete and which lie at the heart of the debate. On top of that, we provide a comparative study of the different technologies applied for efficient portfolio construction and we suggest potential paths for future work that lie at the intersection of the presented techniques.
Abstract: This paper proposes that in the course of evolution
pitch structure became a human specific tool of communication the
function of which is to induce emotional states such as uncertainty
and cohesion. By the means of eliciting these emotions during
collective music performance people are able to unconsciously give
cues concerning social acceptance. This is probably one of the
reasons why in all cultures people collectively perform tonal music. It
is also suggested that tonal pitch structure had been invented socially
before it became an evolutionary innovation of hominines. It means
that a predisposition to tonally organize pitches evolved by the means
of ‘Baldwin effect’ – a process in which natural selection transforms
the learned response of an organism into the instinctive response. In
the proposed, hypothetical evolutionary scenario of the emergence of
tonal pitch structure social forces such as a need for closer
cooperation play the crucial role.
Abstract: Natural dyes are gaining interest due their expected
low risk to human health and to the environment. In this study, the
wash fastness of a natural coloring matter from the liquid waste
produced in the steam treatment of eucalyptus wood in textile fabrics
was investigated. Specifically, eucalyptus wood extract was used to
dye cotton, nylon and wool in an exhaust dyeing process without the
addition of the traditional mordanting agents and then submitted to
wash fastness analysis. The resulting dyed fabrics were evaluated for
color fastness. It was found that wash fastness of dyed fabrics was
very good to cotton and excellent to nylon and wool.
Abstract: This paper introduces a method to optimal design of a
hybrid Wind/Photovoltaic/Fuel cell generation system for a typical
domestic load that is not located near the electricity grid. In this
configuration the combination of a battery, an electrolyser, and a
hydrogen storage tank are used as the energy storage system. The aim
of this design is minimization of overall cost of generation scheme
over 20 years of operation. The Matlab/Simulink is applied for
choosing the appropriate structure and the optimization of system
sizing. A teaching learning based optimization is used to optimize the
cost function. An overall power management strategy is designed for
the proposed system to manage power flows among the different
energy sources and the storage unit in the system. The results have
been analyzed in terms of technical and economic. The simulation
results indicate that the proposed hybrid system would be a feasible
solution for stand-alone applications at remote locations.
Abstract: Background: Diabetic sensorimotor polyneuropathy
(DSP) is one of the most common microvascular complications of
type 2 diabetes. Loss of sensation is thought to contribute to a lack of
static and dynamic stability and increased risk of falling. Purpose:
The purpose of this study was to compare the effects of low-level
laser (LLL) and monochromatic near-infrared photo energy (MIRE)
on pain, cutaneous sensation, static stability, and index of lower limb
blood flow in diabetic patients with peripheral neuropathy. Methods:
Forty diabetic patients with peripheral neuropathy were recruited for
participation in this study. They were divided into two groups: The
MIRE group, which contained 20 patients, and the LLL group, which
contained 20 patients. All patients who participated in the study had
been subjected to various physical assessment procedures, including
pain, cutaneous sensation, Doppler flow meter, and static stability
assessments. The baseline measurements were followed by treatment
sessions that were conducted twice a week for six successive weeks.
Results: The statistical analysis of the data revealed significant
improvement of pain in both groups, with significant improvement in
cutaneous sensation and static balance in the MIRE group compared
to the LLL group; on the other hand, the results showed no
significant differences in lower limb blood flow between the groups.
Conclusion: LLL and MIRE can improve painful symptoms in
patients with diabetic neuropathy. On the other hand, MIRE is also
useful in improving cutaneous sensation and static stability in
patients with diabetic neuropathy.
Abstract: This study discusses a Turkish music education model
similar to its Venezuelan counterpart El Sistema, in which
socialization and human development are the main goals. The Music
for Peace (Baris Icin Muzik) model, founded in 2005 by an idealist
humanitarian in Istanbul, started as a pilot project with accordion and
today makes symphonic music education. The program aims to offer
social change through free-of-charge. In such a big city like Istanbul, in a deprived inner city center
people have poor economic, social and cultural conditions. In that
Edirnekapi district people don’t have opportunities to join the cultural
and social life, like music or sports. It is believed that this initiative
covered a part of this gap by giving children the opportunities to
participate in social and cultural life. In this study it is planned to understand what social changes could
music education could make in children’s lives. In the complimentary
music lessons children works in groups, which helps them to learn
the feelings of solidarity, friendship, communion and sharing. By Music for Peace project children connect with the community,
they have the belief to succeed in life because they feel that they are
loved by their friends, instructors and families. In short they feel that
they are important, thus brings the success in life. Additionally, it is
believed that, this program has achieved success. Today
approximately 400 children participate in this programs orchestras
and choirs. Some of the students get into the conservatories. And the
center is not just a place where they get music lessons but also a place
where they get socialized. And music education helps children to
have strong sense of identity, self-confidence and self-esteem.
Abstract: Graphene was dispersed using a tip sonicator and the
effect of surfactants were analysed. Sodium Dodecyl Sulphate (SDS)
and Polyvinyl Alcohol (PVA) were compared to observe whether or
not they had any effect on any de-wrinkling, and secondly whether
they aided to achieve better dispersions. There is a huge demand for
wrinkle free graphene as this will greatly increase its usefulness in
various engineering applications. A comprehensive literature on dewrinkling
graphene has been discussed. Low magnification Scanning
Electronic Microscopy (SEM) was conducted to assess the quality of
graphene de-wrinkling. The utilization of the PVA has significant
effect on de-wrinkling whereas SDS had minimal effect on the dewrinkling
of graphene.
Abstract: The growing number of computer viruses and the
detection of zero day malware have been the concern for security
researchers for a large period of time. Existing antivirus products
(AVs) rely on detecting virus signatures which do not provide a full
solution to the problems associated with these viruses. The use of
logic formulae to model the behaviour of viruses is one of the most
encouraging recent developments in virus research, which provides
alternatives to classic virus detection methods. In this paper, we
proposed a comparative study about different virus detection
techniques. This paper provides the advantages and drawbacks of
different detection techniques. Different techniques will be used in
this paper to provide a discussion about what technique is more
effective to detect computer viruses.
Abstract: In this paper, relationship between different properties
of IC concrete and water cement ratio, obtained from a
comprehensive experiment conducted on IC using local materials
(Burnt clay chips- BC) is presented. In addition, saturated SAP was
used as an IC material in some cases. Relationships have been
developed through regression analysis. The focus of this analysis is
on developing relationship between a dependent variable and an
independent variable. Different percent replacements of BC and
water cement ratios were used. Compressive strength, modulus of
elasticity, water permeability and chloride permeability were tested
and variations of these parameters were analyzed with respect to
water cement ratio.
Abstract: Investigating the dynamic responses of high rise
structures under the effect of siesmic ground motion is extremely
important for the proper analysis and design of multitoried structures.
Since the presence of infilled walls strongly influences the behaviour
of frame systems in multistoried buildings, there is an increased need
for developing guidelines for the analysis and design of infilled
frames under the effect of dynamic loads for safe and proper design
of buildings. In this manuscript, we evaluate the natural frequencies
and natural periods of single bay single storey frames considering the
effect of infill walls by using the Eigen value analysis and validating
with SAP 2000 (free vibration analysis). Various parameters obtained
from the diagonal strut model followed for the free vibration analysis
is then compared with the Finite Element model, where infill is
modeled as shell elements (four noded). We also evaluated the effect
of various parameters on the natural periods of vibration obtained by
free vibration analysis in SAP 2000 comparing them with those
obtained by the empirical expressions presented in I.S. 1893(Part I)-
2002.
Abstract: Adequate analgesia following caesarean section
decreases morbidity, hastens ambulation, improves patient outcome
and facilitates care of the newborn. Intrathecal magnesium, an
NMDA antagonist, has been shown to prolong analgesia without
significant side effects in healthy parturients. The aim of this study
was to evaluate the onset and duration of sensory and motor block,
hemodynamic effect, postoperative analgesia, and adverse effects of
magnesium or fentanyl given intrathecally with hyperbaric 0.5%
bupivacaine in patients with mild preeclampsia undergoing caesarean
section. Sixty women with mild preeclampsia undergoing elective
caesarean section were included in a prospective, double blind,
controlled trial. Patients were randomly assigned to receive spinal
anesthesia with 2 mL 0.5% hyperbaric bupivacaine with 12.5 μg
fentanyl (group F) or 0.1 ml of 50% magnesium sulphate (50 mg)
(group M) with 0.15ml preservative free distilled water. Onset,
duration and recovery of sensory and motor block, time to maximum
sensory block, duration of spinal anaesthesia and postoperative
analgesic requirements were studied. Statistical comparison was
carried out using the Chi-square or Fisher’s exact tests and
Independent Student’s t-test where appropriate. The onset of both
sensory and motor block was slower in the magnesium group. The
duration of spinal anaesthesia (246 vs. 284) and motor block (186.3
vs. 210) were significantly longer in the magnesium group. Total
analgesic top up requirement was less in group M. Hemodynamic
parameters were similar in both the groups. Intrathecal magnesium
caused minimal side effects. Since Fentanyl and other opioid
congeners are not available throughout the country easily,
magnesium with its easy availability and less side effect profile can
be a cost effective alternative to fentanyl in managing pregnancy
induced hypertension (PIH) patients given along with Bupivacaine
intrathecally in caesarean section.
Abstract: The primary objective of this work was to study the
effect of resin chemistry, pH and molarity of binding and elution
buffer on aggregate removal using Cation Exchange Chromatography
and find the optimum conditions which can give efficient aggregate
removal with minimum loss of yield. Four different resins were used
for carrying out the experiments: Fractogel EMD SO3
-(S), Fractogel EMD COO-(M), Capto SP ImpRes and S Ceramic HyperD. Runs
were carried out on the AKTA Avant system. Design of Experiments
(DOE) was used for analysis using the JMP software. The
dependence of the yield obtained using different resins on the
operating conditions was studied. Success has been achieved in
obtaining yield greater than 90% using Capto SP ImpRes and
Fractogel EMD COO-(M) resins. It has also been found that a change
in the operating conditions generally has different effects on the
yields obtained using different resins.
Abstract: Multiple-input multiple-output (MIMO) radar has
received increasing attention in recent years. MIMO radar has many
advantages over conventional phased array radar such as target
detection,resolution enhancement, and interference suppression. In
this paper, the results are presented from a simulation study of MIMO
uniformly-spaced linear array (ULA) antennas. The performance is
investigated under varied parameters, including varied array size,
pseudo random (PN) sequence length, number of snapshots, and
signal to noise ratio (SNR). The results of MIMO are compared to a
traditional array antenna.
Abstract: Mobile Ad Hoc Networks (MANETs) is a collection
of mobile devices forming a communication network without
infrastructure. MANET is vulnerable to security threats due to
network’s limited security, dynamic topology, scalability and the lack
of central management. The Quality of Service (QoS) routing in such
networks is limited by network breakage caused by node mobility or
nodes energy depletions. The impact of node mobility on trust
establishment is considered and its use to propagate trust through a
network is investigated in this paper. This work proposes an
enhanced Associativity Based Routing (ABR) with Fuzzy based
Trust (Fuzzy- ABR) routing protocol for MANET to improve QoS
and to mitigate network attacks.
Abstract: In this paper numerical studies have been carried out
to examine the pre-ignition flow features of high-performance solid
propellant rocket motors with two different port geometries but with
same propellant loading density. Numerical computations have been
carried out using a validated 3D, unsteady, 2nd-order implicit, SST k-
ω turbulence model. In the numerical study, a fully implicit finite
volume scheme of the compressible, Reynolds-Averaged, Navier-
Stokes equations is employed. We have observed from the numerical
results that in solid rocket motors with highly loaded propellants
having divergent port geometry the hot igniter gases can create preignition
pressure oscillations leading to thrust oscillations due to the
flow unsteadiness and recirculation. We have also observed that the
igniter temperature fluctuations are diminished rapidly thereby
reaching the steady state value faster in the case of solid propellant
rocket motors with convergent port than the divergent port
irrespective of the igniter total pressure. We have concluded that the
prudent selection of the port geometry, without altering the propellant
loading density, for damping the total temperature fluctuations within
the motor is a meaningful objective for the suppression and control of
instability and/or thrust oscillations often observed in solid propellant
rocket motors with non-uniform port geometry.
Abstract: The aim of the current work was to employ the finite
element method to model a slab, with a small hole across its width,
undergoing plastic plane strain deformation. The computational
model had, however, to be validated by comparing its results with
those obtained experimentally. Since they were in good agreement,
the finite element method can therefore be considered a reliable tool
that can help gain better understanding of the mechanism of ductile
failure in structural members having stress raisers. The finite element
software used was ANSYS, and the PLANE183 element was utilized.
It is a higher order 2-D, 8-node or 6-node element with quadratic
displacement behavior. A bilinear stress-strain relationship was used
to define the material properties, with constants similar to those of the
material used in the experimental study. The model was run for
several tensile loads in order to observe the progression of the plastic
deformation region, and the stress concentration factor was
determined in each case. The experimental study involved employing the visioplasticity
technique, where a circular mesh (each circle was 0.5 mm in
diameter, with 0.05 mm line thickness) was initially printed on the
side of an aluminum slab having a small hole across its width.
Tensile loading was then applied to produce a small increment of
plastic deformation. Circles in the plastic region became ellipses,
where the directions of the principal strains and stresses coincided
with the major and minor axes of the ellipses. Next, we were able to
determine the directions of the maximum and minimum shear
stresses at the center of each ellipse, and the slip-line field was then
constructed. We were then able to determine the stress at any point in
the plastic deformation zone, and hence the stress concentration
factor. The experimental results were found to be in good agreement
with the analytical ones.
Abstract: A new design of aerostatic thrust bearing is proposed
for high static stiffness. The bearing body, which is mead of polymer
covered with metallic membrane, is held by a circular ring. Such a
support helps form a concave air gap to grasp the air pressure. The
polymer body, which can be made rapidly by either injection or
molding is able to provide extra damping under dynamic loading. The
smooth membrane not only serves as the bearing surface but also
protects the polymer body. The restrictor is a capillary inside a silicone
tube. It can passively compensate the variation of load by expanding
the capillary diameter for more air flux. In the present example, the
stiffness soars from 15.85 N/μm of typical bearing to 349.85 N/μm at
bearing elevation 9.5 μm; meanwhile the load capacity also enhances
from 346.86 N to 704.18 N.
Abstract: Traditional mechanical control systems in thrust
vectoring are efficient in rocket thrust guidance but their costs
and their weights are excessive. The fluidic injection in the nozzle
divergent constitutes an alternative procedure to achieve the goal. In
this paper, we present a 3D analytical model for fluidic injection
in a supersonic nozzle integrating an orifice. The fluidic vectoring
uses a sonic secondary injection in the divergent. As a result, the
flow and interaction between the main and secondary jet has built in
order to express the pressure fields from which the forces and thrust
vectoring are deduced. Under various separation criteria, the present
analytical model results are compared with the existing numerical
and experimental data from the literature.
Abstract: This paper presents a study on the effect of
second-order slip and jump on forced convection through a long
isothermally heated or cooled planar microchannel. The fully
developed solutions of thermal flow fields are analytically obtained on
the basis of the second-order Maxwell-Burnett slip and Smoluchowski
jump boundary conditions. Results reveal that the second-order term in
the Karniadakis slip boundary condition is found to contribute a
negative velocity slip and then to lead to a higher pressure drop as well
as a higher fluid temperature for the heated-wall case or to a lower
fluid temperature for the cooled-wall case. These findings are contrary
to predictions made by the Deissler model. In addition, the role of
second-order slip becomes more significant when the Knudsen
number increases.
Abstract: Concrete is strong in compression however weak in
tension. The tensile strength as well as ductile property of concrete
could be improved by addition of short dispersed fibers. Polyethylene
terephthalate (PET) fiber obtained from hand cutting or mechanical
slitting of plastic sheets generally used as discrete reinforcement in
substitution of steel fiber. PET fiber obtained from the former process
is in the form of straight slit sheet pattern that impart weaker
mechanical bonding behavior in the concrete matrix. To improve the
limitation of straight slit sheet fiber the present study considered two
additional geometry of fiber namely (a) flattened end slit sheet and
(b) deformed slit sheet. The mix for plain concrete was design for a
compressive strength of 25 MPa at 28 days curing time with a watercement
ratio of 0.5. Cylindrical and beam specimens with 0.5% fibers
volume fraction and without fibers were cast to investigate the
influence of geometry on the mechanical properties of concrete. The
performance parameters mainly studied include flexural strength,
splitting tensile strength, compressive strength and ultrasonic pulse
velocity (UPV). Test results show that geometry of fiber has a
marginal effect on the workability of concrete. However, it plays a
significant role in achieving a good compressive and tensile strength
of concrete. Further, significant improvement in term of flexural and
energy dissipation capacity were observed from other fibers as
compared to the straight slit sheet pattern. Also, the inclusion of PET
fiber improved the ability in absorbing energy in the post-cracking
state of the specimen as well as no significant porous structures.