Abstract: Vertical Handover(VHO) among different
communication technologies ensuring uninterruption and service
continuity is one of the most important performance parameter in
Heterogenous networks environment. In an integrated Universal
Mobile Telecommunicatin System(UMTS) and Wireless Local
Area Network(WLAN), WLAN is given an inherent priority over
UMTS because of its high data rates with low cost. Therefore
mobile users want to be associated with WLAN maximum of the
time while roaming, to enjoy best possible services with low cost.
That encourages reduction of number of VHO. In this work the
reduction of number of VHO with respect to varying number of
WLAN Access Points(APs) in an integrated UMTS and WLAN
network is investigated through simulation to provide best possible
cost effective service to the users. The simulation has been carried
out for an area (7800 × 9006)m2 where COST-231 Hata model
and 3GPP (TR 101 112 V 3.1.0) specified models are used for
WLAN and UMTS path loss models respectively. The handover
decision is triggered based on the received signal level as compared
to the fade margin. Fade margin gives a probabilistic measure of
the reliability of the communication link. A relationship between
number of WLAN APs and the number of VHO is also established
in this work.
Abstract: In this paper, the transient device performance analysis
of n-type Gate Inside JunctionLess Transistor (GI-JLT) has been
evaluated. 3-D Bohm Quantum Potential (BQP) transport device
simulation has been used to evaluate the delay and power dissipation
performance. GI-JLT has a number of desirable device parameters
such as reduced propagation delay, dynamic power dissipation,
power and delay product, intrinsic gate delay and energy delay
product as compared to Gate-all-around transistors GAA-JLT. In
addition to this, various other device performance parameters namely,
on/off current ratio, short channel effects (SCE), transconductance
Generation Factor (TGF) and unity gain cut-off frequency (fT ) and
subthreshold slope (SS) of the GI-JLT and GAA-JLT have been
analyzed and compared. GI-JLT shows better device performance
characteristics than GAA-JLT for low power and high frequency
applications, because of its larger gate electrostatic control on the
device operation.
Abstract: This paper focuses on the assessment of the air
pollution and morbidity relationship in Tunisia. Air pollution is
measured by ozone air concentration and the morbidity is measured
by the number of respiratory-related restricted activity days during
the 2-week period prior to the interview. Socioeconomic data are also
collected in order to adjust for any confounding covariates. Our
sample is composed by 407 Tunisian respondents; 44.7% are women,
the average age is 35.2, near 69% are living in a house built after
1980, and 27.8% have reported at least one day of respiratory-related
restricted activity. The model consists on the regression of the
number of respiratory-related restricted activity days on the air
quality measure and the socioeconomic covariates. In order to correct
for zero-inflation and heterogeneity, we estimate several models
(Poisson, negative binomial, zero inflated Poisson, Poisson hurdle,
negative binomial hurdle and finite mixture Poisson models).
Bootstrapping and post-stratification techniques are used in order to
correct for any sample bias. According to the Akaike information
criteria, the hurdle negative binomial model has the greatest goodness
of fit. The main result indicates that, after adjusting for
socioeconomic data, the ozone concentration increases the probability
of positive number of restricted activity days.
Abstract: In this paper cognitive radio is presented and the
spectrum overlay cognitive radio antenna system is detailed. A UWB
antenna with frequency reconfigurable characteristics is proposed.
The reconfigurability is achieved when the filter is integrated to the
feeding line of the single port overlay cognitive radio. When
activated, the filter can transform the UWB frequency response into a
reconfigurable narrowband one, which is suitable for the
communication operation of the CR system. Here single port overlay
cognitive radio antenna is designed and simulated using Ansoft High
Frequency Structure Simulator (HFSS).
Abstract: Photonic Crystal Fibers (PCFs) can be used in optical
communications as transmission lines. For this reason, the PCFs with
low confinement loss, low chromatic dispersion, and low nonlinear
effects are highly suitable transmission media. In this paper, we
introduce a new design of index-guiding nanostructured photonic
crystal fiber (IG-NPCF) with ultra-low chromatic dispersion, low
nonlinearity effects, and low confinement loss. Relatively low
dispersion is achieved in the wavelength range of 1200 to 1600nm
using the proposed design. According to the new structure of
nanostructured PCF presented in this study, the chromatic dispersion
slope is -30(ps/km.nm) and the confinement loss reaches below 10-7
dB/km. While in the wavelength range mentioned above at the same
time an effective area of more than 50.2μm2 is obtained.
Abstract: In this paper a new algorithm to generate random
simple polygons from a given set of points in a two dimensional
plane is designed. The proposed algorithm uses a genetic algorithm to
generate polygons with few vertices. A new merge algorithm is
presented which converts any two polygons into a simple polygon.
This algorithm at first changes two polygons into a polygonal chain
and then the polygonal chain is converted into a simple polygon. The
process of converting a polygonal chain into a simple polygon is
based on the removal of intersecting edges. The experiments results
show that the proposed algorithm has the ability to generate a great
number of different simple polygons and has better performance in
comparison to celebrated algorithms such as space partitioning and
steady growth.
Abstract: In this study, data loss tolerance of Support Vector Machines (SVM) based activity recognition model and multi activity classification performance when data are received over a lossy wireless sensor network is examined. Initially, the classification algorithm we use is evaluated in terms of resilience to random data loss with 3D acceleration sensor data for sitting, lying, walking and standing actions. The results show that the proposed classification method can recognize these activities successfully despite high data loss. Secondly, the effect of differentiated quality of service performance on activity recognition success is measured with activity data acquired from a multi hop wireless sensor network, which introduces high data loss. The effect of number of nodes on the reliability and multi activity classification success is demonstrated in simulation environment. To the best of our knowledge, the effect of data loss in a wireless sensor network on activity detection success rate of an SVM based classification algorithm has not been studied before.
Abstract: Cloud computing (CC) has already gained overall
appreciation in research and practice. Whereas the willingness to
integrate cloud services in various IT environments is still unbroken,
the previous CC procurement processes run mostly in an unorganized
and non-standardized way. In practice, a sufficiently specific, yet
applicable business process for the important acquisition phase is
often lacking. And research does not appropriately remedy this
deficiency yet. Therefore, this paper introduces a field-tested
approach for CC procurement. Based on an extensive literature
review and augmented by expert interviews, we designed a model
that is validated and further refined through an in-depth real-life case
study. For the detailed process description, we apply the event-driven
process chain notation (EPC). The gained valuable insights into the
case study may help CC research to shift to a more socio-technical
area. For practice, next to giving useful organizational instructions
we will provide extended checklists and lessons learned.
Abstract: An exploration of the related literature reveals that all
instruction methods aim at training autonomous learners. After the
turn of second language pedagogy toward learner-oriented strategies,
learners’ needs were more focused. Yet; the historical, social and
political aspects of learning were still neglected. The present study
investigates the notion of autonomous learning and explains its
various facets from a pedagogical point of view. Furthermore;
different elements, fields and scopes of autonomous learning will be
explored. After exploring different aspects of autonomy, it is
postulated that liberatory autonomy is highlighted since it not only
covers social autonomy but also reveals learners’ capabilities and
human potentials. It is also recommended that learners consider
different elements of autonomy such as motivation, knowledge,
confidence, and skills.
Abstract: In-memory database systems are becoming popular
due to the availability and affordability of sufficiently large RAM and
processors in modern high-end servers with the capacity to manage
large in-memory database transactions. While fast and reliable inmemory
systems are still being developed to overcome cache misses,
CPU/IO bottlenecks and distributed transaction costs, disk-based data
stores still serve as the primary persistence. In addition, with the
recent growth in multi-tenancy cloud applications and associated
security concerns, many organisations consider the trade-offs and
continue to require fast and reliable transaction processing of diskbased
database systems as an available choice. For these
organizations, the only way of increasing throughput is by improving
the performance of disk-based concurrency control. This warrants a
hybrid database system with the ability to selectively apply an
enhanced disk-based data management within the context of inmemory
systems that would help improve overall throughput.
The general view is that in-memory systems substantially
outperform disk-based systems. We question this assumption and
examine how a modified variation of access invariance that we call
enhanced memory access, (EMA) can be used to allow very high
levels of concurrency in the pre-fetching of data in disk-based
systems. We demonstrate how this prefetching in disk-based systems
can yield close to in-memory performance, which paves the way for
improved hybrid database systems. This paper proposes a novel EMA
technique and presents a comparative study between disk-based EMA
systems and in-memory systems running on hardware configurations
of equivalent power in terms of the number of processors and their
speeds. The results of the experiments conducted clearly substantiate
that when used in conjunction with all concurrency control
mechanisms, EMA can increase the throughput of disk-based systems
to levels quite close to those achieved by in-memory system. The
promising results of this work show that enhanced disk-based
systems facilitate in improving hybrid data management within the
broader context of in-memory systems.
Abstract: Proof of controlling crack width is a basic condition
for securing suitable performance in serviceability limit state. The
cracking in concrete can occur at any time from the casting of time to
the years after the concrete has been set in place. Most codes struggle
with offering procedure for crack width calculation. There is lack in
availability of design charts for designers to compute crack width
with ease. The focus of the study is to utilize design charts and
parametric equations in calculating crack width with minimum error.
The paper contains a simplified procedure to calculate crack width
for reinforced concrete (RC) sections subjected to bending with axial
tensile force following the guidelines of Euro code [DS EN-1992-1-1
& DS EN-1992-1-2]. Numerical examples demonstrate the
application of the suggested procedure. Comparison with parallel
analytical tools supports the validity of result and show the
percentage deviation of crack width in both the procedures. The
technique is simple, user friendly and ready to evolve for a greater
spectrum of section sizes and materials.
Abstract: Electric vehicles are one of the most complicated
electric devices to simulate due to the significant number of different
processes involved in electrical structure of it. There are concurrent
processes of energy consumption and generation with different
onboard systems, which make simulation tasks more complicated to
perform. More accurate simulation on energy consumption can
provide a better understanding of all energy management for electric
transport. As a result of all those processes, electric transport can
allow for a more sustainable future and become more convenient in
relation to the distance range and recharging time. This paper
discusses the problems of energy consumption simulations for
electric vehicles using different software packages to provide ideas
on how to make this process more precise, which can help engineers
create better energy management strategies for electric vehicles.
Abstract: Wet scrubbers have found widespread use in cleaning
contaminated gas streams because of their ability to remove
particulates and based on the applications of scrubbing of marine
engine exhaust gases by spraying sea-water. In order to examine the
flow characteristics inside the scrubber, the model is designated with
flow properties of hot air and water sprayer. The flow dynamics of
evaporation of hot air by the injection of water droplets is the key
factor considered in this paper. The flow behavior inside the scrubber
was investigated from the previous works and to sum up the
evaporation rate with respect to the concentration of water droplets are
predicted to bring out the competent modelling. The numerical
analysis using CFD facilitates in understanding the problem better and
empathies the behavior of the model over its entire operating envelope.
Abstract: In this paper we describe the Levenvberg-Marquardt
(LM) algorithm for identification and equalization of CDMA
signals received by an antenna array in communication channels.
The synthesis explains the digital separation and equalization of
signals after propagation through multipath generating intersymbol
interference (ISI). Exploiting discrete data transmitted and three
diversities induced at the reception, the problem can be composed
by the Block Component Decomposition (BCD) of a tensor of
order 3 which is a new tensor decomposition generalizing the
PARAFAC decomposition. We optimize the BCD decomposition by
Levenvberg-Marquardt method gives encouraging results compared to
classical alternating least squares algorithm (ALS). In the equalization
part, we use the Minimum Mean Square Error (MMSE) to perform
the presented method. The simulation results using the LM algorithm
are important.
Abstract: Cost of governance in Nigeria has become a challenge
to development and concern to practitioners and scholars alike in the
field of business and social science research. In the 2010 national
budget of NGN4.6 trillion or USD28.75billion for instance, only a
pantry sum of NGN1.8trillion or USD11.15billion was earmarked for
capital expenditure. Similarly, in 2013, out of a total national budget
of NGN4.92trillion or USD30.75billion, only the sum of
NGN1.50trllion or USD9.38billion was voted for capital expenditure.
Therefore, based on the data sourced from the Nigerian Office of
Statistics, Central bank of Nigeria Statistical Bulletin as well as from
the United Nations Development Programme, this study examined
the causes of high cost of governance in Nigeria. It found out that the
high cost of governance in the country is in the interest of the ruling
class, arising from their unethical behaviour – corrupt practices and
the poor management of public resources. As a result, the study
recommends the need to intensify the war against corruption and
mismanagement of public resources by government officials as
possible solution to overcome the high cost of governance in Nigeria.
This could be achieved by strengthening the constitutional powers of
the various anti-corruption agencies in the area of arrest, investigation
and prosecution of offenders without the interference of the executive
arm of government either at the local, state or federal level.
Abstract: In the present study, mixed convection in a horizontal
rectangular duct using Al2O3 is numerically investigated. The effects
of different Rayleigh number, Reynolds number and radiation on
flow and heat transfer characteristics are studied in detail. This study
covers Rayleigh number in the range of 2 × 10^6 ≤ Ra ≤ 2 × 10^7 and
Reynolds number in the range of 100 ≤ Re ≤ 1100. Results reveal that
the Nusselt number increases as Reynolds and Rayleigh numbers
increase. It is also found that the dimensionless temperature
distribution increases as Rayleigh number increases.
Abstract: The Roma (Gypsies) is a transnational minority with a
high degree of consanguineous marriages. Similar to other
genetically isolated founder populations, the Roma harbor a number
of unique or rare genetic disorders. This paper discusses about a rare
form of Charcot-Marie-Tooth disease – type 4G (CMT4G), also
called Hereditary Motor and Sensory Neuropathy type Russe, an
autosomal recessive disease caused by mutation private to Roma
characterized by abnormally increased density of non-myelinated
axons. CMT4G was originally found in Bulgarian Roma and in 2009
two putative causative mutations in the HK1 gene were identified.
Since then, several cases were reported in Roma families mainly
from Bulgaria and Spain. Here we present a Slovak Roma family in
which CMT4G was diagnosed on the basis of clinical examination
and genetic testing. This case is a further proof of the role of the HK1
gene in pathogenesis of the disease. It confirms that mutation in the
HK1 gene is a common cause of autosomal recessive CMT disease in
Roma and should be considered as a common part of a diagnostic
procedure.
Abstract: Monoamine oxidase A gene (MAOA) is suggested to
be a candidate gene implicated in many neuropsychiatric disorders,
including autism spectrum disorder (ASD). This meta-analytic review
evaluates the relationship between ASD and MAOA markers such as
30 bp variable number tandem repeats in the promoter region
(uVNTR) and single nucleotide polymorphisms (SNPs) by using
findings from recently published studies. It seems that in Caucasian
males, the risk of developing ASD increase with the presence of 4-
repeat allele in the promoter region of MAOA gene whereas no
differences were found between autistic patients and controls in
Egyptian, West Bengal and Korean population. Some studies point to
the importance of specific haplotype groups of SNPs and interaction
of MAOA with others genes (e. g. FOXP2 or SRY). The results of
existing studies are insufficient and further research is needed.
Abstract: The Simulation based VLSI Implementation of
FELICS (Fast Efficient Lossless Image Compression System)
Algorithm is proposed to provide the lossless image compression and
is implemented in simulation oriented VLSI (Very Large Scale
Integrated). To analysis the performance of Lossless image
compression and to reduce the image without losing image quality
and then implemented in VLSI based FELICS algorithm. In FELICS
algorithm, which consists of simplified adjusted binary code for
Image compression and these compression image is converted in
pixel and then implemented in VLSI domain. This parameter is used
to achieve high processing speed and minimize the area and power.
The simplified adjusted binary code reduces the number of arithmetic
operation and achieved high processing speed. The color difference
preprocessing is also proposed to improve coding efficiency with
simple arithmetic operation. Although VLSI based FELICS
Algorithm provides effective solution for hardware architecture
design for regular pipelining data flow parallelism with four stages.
With two level parallelisms, consecutive pixels can be classified into
even and odd samples and the individual hardware engine is
dedicated for each one. This method can be further enhanced by
multilevel parallelisms.
Abstract: This paper describes a novel application of Fiber
Braggs Grating (FBG) sensors in the assessment of human postural
stability and balance on an unstable platform. In this work, FBG
sensor Stability Analyzing Device (FBGSAD) is developed for
measurement of plantar strain to assess the postural stability of
subjects on unstable platforms during different stances in eyes open
and eyes closed conditions on a rocker board. The studies are
validated by comparing the Centre of Gravity (CG) variations
measured on the lumbar vertebra of subjects using a commercial
accelerometer. The results obtained from the developed FBGSAD
depict qualitative similarities with the data recorded by commercial
accelerometer. The advantage of the FBGSAD is that it measures
simultaneously plantar strain distribution and postural stability of the
subject along with its inherent benefits like non-requirement of
energizing voltage to the sensor, electromagnetic immunity and
simple design which suits its applicability in biomechanical
applications. The developed FBGSAD can serve as a tool/yardstick to
mitigate space motion sickness, identify individuals who are
susceptible to falls and to qualify subjects for balance and stability,
which are important factors in the selection of certain unique
professionals such as aircraft pilots, astronauts, cosmonauts etc.