Abstract: Powerline Communications –PLC– as an alternative
method for broadband networking, has the advantage of transmitting
over channels already used for electrical distribution or even
transmission. But these channels have been not designed with usual
wired channels requirements for broadband applications such as
stable impedance or known attenuation, and the network have to
reject noises caused by electrical appliances that share the same
channel. Noise control standards are difficult to complain or simply
do not exist on Latin-American environments. This paper analyzes
PLC throughput for home connectivity by probing noisy channel
scenarios in a PLC network and the statistical results are shown.
Abstract: This paper describes the application of a model predictive controller to the problem of batch reactor temperature control. Although a great deal of work has been done to improve reactor throughput using batch sequence control, the control of the actual reactor temperature remains a difficult problem for many operators of these processes. Temperature control is important as many chemical reactions are sensitive to temperature for formation of desired products. This controller consist of two part (1) a nonlinear control method GLC (Global Linearizing Control) to create a linear model of system and (2) a Model predictive controller used to obtain optimal input control sequence. The temperature of reactor is tuned to track a predetermined temperature trajectory that applied to the batch reactor. To do so two input signals, electrical powers and the flow of coolant in the coil are used. Simulation results show that the proposed controller has a remarkable performance for tracking reference trajectory while at the same time it is robust against noise imposed to system output.
Abstract: This paper presents design and characterization of a
microaccelerometer designated for integration into cataract surgical
probe to detect hardness of different eye tissues during cataract
surgery. Soft posterior lens capsule of eye can be easily damaged in
comparison with hard opaque lens since the surgeon can not see
directly behind cutting needle during the surgery. Presence of
microsensor helps the surgeon to avoid rupturing posterior lens
capsule which if occurs leads to severe complications such as
glaucoma, infection, or even blindness. The microsensor having
overall dimensions of 480 μm x 395 μm is able to deliver significant
capacitance variations during encountered vibration situations which
makes it capable to distinguish between different types of tissue.
Integration of electronic components on chip ensures high level of
reliability and noise immunity while minimizes space and power
requirements. Physical characteristics and results on performance
testing, proves integration of microsensor as an effective tool to aid
the surgeon during this procedure.
Abstract: The one of best robust search technique on large scale
search area is heuristic and meta heuristic approaches. Especially in
issue that the exploitation of combinatorial status in the large scale
search area prevents the solution of the problem via classical
calculating methods, so such problems is NP-complete. in this
research, the problem of winner determination in combinatorial
auctions have been formulated and by assessing older heuristic
functions, we solve the problem by using of genetic algorithm and
would show that this new method would result in better performance
in comparison to other heuristic function such as simulated annealing
greedy approach.
Abstract: The number of people using SNS with their mobile devices is soaring. This research focuses on the Twitter service that has the most third-party applications and delved into the fact that there were not sufficient studies on the UX design aspects of Twitter applications. Among social network services which have emerged as a major social topic lately, this research try to analyze the UX design of the Twitter application which is also called micro-blogging service. Therefore this research sets its goal to draw components of the UX design aspect of the Tweeter application on which there are not enough analysis yet. Moreover, this research suggests improvement of mobile application which will assure better users- experience. In order to analyze the UX design aspect of the mobile twitter application, with relevant document and user research, evaluating factors of the UX Design which would affect users- experience were organized. The subjects for cases were selected among six paid and free social networking applications that had been consistently ranked from 1st to 100th in the Korean application store during May, 2012 after closely monitoring the rank. From May 15th to May 11th in 2012, in accordance with the evaluating standard, surveys were conducted in a form of interviews with 20 subjects who have used the Twitter application to find out problems and solutions for the UX design of the mobile Twitter application.
Abstract: The corrugated steel cladding used to cover most of
steel buildings is considered as non-structural element. This research
will reflect the effect of cladding as a shear diaphragm in increasing
the normal elastic capacity of columns. This study is important
because of the lack of information of the behavior of cladding and
secondary members in various codes. Mathematical models for six
different cases are carried by software. The results extracted from the
program have been plotted showing the effects of different variables
on the ultimate load of column. The variables considered in our
research are the spacing between columns and the thickness of the
corrugated sheet representing the sheet stiffness.
Abstract: The purpose of the study was to determine the amount of Palm Kernel Oil (PKO) extracted from a packed bed of palm kernels in a supercritical fluid extractor using supercritical carbon dioxide (SC-CO2) as an environmental friendly solvent. Further, the study sought to ascertain the values of the overall mass transfer coefficient (K) of PKO evaluation through a mass transfer model, at constant temperature of 50 °C, 60 °C, and 70 °C and pressures range from 27.6 MPa, 34.5 MPa, 41.4 MPa and 48.3 MPa respectively. Finally, the study also seeks to demonstrate the application of the overall mass transfer coefficient values in relation to temperature and pressure. The overall mass transfer coefficient was found to be dependent pressure at each constant temperature of 50 °C, 60 °C and 70 °C. The overall mass transfer coefficient for PKO in a packed bed of palm kernels was found to be in the range of 1.21X 10-4 m min-1 to 1.72 X 10-4 m min-1 for a constant temperature of 50 °C and in the range of 2.02 X 10-4 m min-1 to 2.43 X 10-4 m min-1 for a constant temperature of 60 °C. Similar increasing trend of the overall mass transfer coefficient from 1.77 X 10-4 m min-1 to 3.64 X 10-4 m min-1 was also observed at constant temperature of 70 °C within the same pressure range from 27.6 MPa to 48.3 MPa.
Abstract: In this study two series of self compacting concrete
mixtures were prepared with 100% coarse recycled concrete
aggregates and different percentages of 0%, 20%, 40%, 60%, 80%
and 100% fine recycled concrete aggregates. In series I and II the
water to binder ratios were 0.50 and 0.45, respectively. The cement
content was kept 350
3 m
kg for those mixtures that don't have any
Nano-Silica. To improve the compressive strength of samples, Nano-
Silica replaced with 10% of cement weight in concrete mixtures. By
doing the tests, the results showed that, adding Nano-silica to the
samples with less percentage of fine recycled concrete aggregates,
lead to more increase on the compressive strength.
Abstract: The proposed Multimedia Pronunciation Learning
Management System (MPLMS) in this study is a technology with
profound potential for inducing improvement in pronunciation
learning. The MPLMS optimizes the digitised phonetic symbols with
the integration of text, sound and mouth movement video. The
components are designed and developed in an online management
system which turns the web to a dynamic user-centric collection of
consistent and timely information for quality sustainable learning.
The aim of this study is to design and develop the MPLMS which
serves as an innovative tool to improve English pronunciation. This
paper discusses the iterative methodology and the three-phase Alessi
and Trollip model in the development of MPLMS. To align with the
flexibility of the development of educational software, the iterative
approach comprises plan, design, develop, evaluate and implement is
followed. To ensure the instructional appropriateness of MPLMS, the
instructional system design (ISD) model of Alessi and Trollip serves
as a platform to guide the important instructional factors and process.
It is expected that the results of future empirical research will support
the efficacy of MPLMS and its place as the premier pronunciation
learning system.
Abstract: This paper examines the forced convection flow of
incompressible, electrically conducting viscous fluid past a sharp
wedge in the presence of heat generation or absorption with an
applied magnetic field. The system of partial differential equations
governing Falkner - Skan wedge flow and heat transfer is first
transformed into a system of ordinary differential equations using
similarity transformations which is later solved using an implicit
finite - difference scheme, along with quasilinearization technique.
Numerical computations are performed for air (Pr = 0.7) and
displayed graphically to illustrate the influence of pertinent physical
parameters on local skin friction and heat transfer coefficients and,
also on, velocity and temperature fields. It is observed that the
magnetic field increases both the coefficients of skin friction and heat
transfer. The effect of heat generation or absorption is found to be
very significant on heat transfer, but its effect on the skin friction is
negligible. Indeed, the occurrence of overshoot is noticed in the
temperature profiles during heat generation process, causing the
reversal in the direction of heat transfer.
Abstract: We study bifurcation structure of the zonal jet flow the
streamfunction of which is expressed by a single spherical harmonics
on a rotating sphere. In the non-rotating case, we find that a steady
traveling wave solution arises from the zonal jet flow through Hopf
bifurcation. As the Reynolds number increases, several traveling
solutions arise only through the pitchfork bifurcations and at high
Reynolds number the bifurcating solutions become Hopf unstable. In
the rotating case, on the other hand, under the stabilizing effect of
rotation, as the absolute value of rotation rate increases, the number
of the bifurcating solutions arising from the zonal jet flow decreases
monotonically. We also carry out time integration to study unsteady
solutions at high Reynolds number and find that in the non-rotating
case the unsteady solutions are chaotic, while not in the rotating cases
calculated. This result reflects the general tendency that the rotation
stabilizes nonlinear solutions of Navier-Stokes equations.
Abstract: The study aimed to identify the nature of autistic
talent, the manifestations of their weak central coherence, and their
sensory characteristics. The case study consisted of four talented
autistic males. Two of them in drawing, one in clay formation and
one in jigsaw puzzle. Tools of data collection were Group Embedded
Figures Test, Block Design Test, Sensory Profile Checklist Revised,
Interview forms and direct observation. Results indicated that talent
among autistics emerges in limited domain and being extraordinary
for each case. Also overlapping construction properties. Indeed, they
show three perceptual aspects of weak central coherence: The weak
in visual spatial-constructional coherence, the weak in perceptual
coherence and the weak in verbal – semantic coherence. Moreover,
the majority of the study cases used the three strategies of weak
central coherence (segmentation, obliqueness and rotation). As for
the sensory characteristics, all study cases have numbers of that
characteristics that especially emerges in the visual system.
Abstract: This paper presents the simulation the results of
electric field and potential distributions along surface of silicone
rubber polymer insulators. Near the same leakage distance subjected
to 15 kV in 50 cycle salt fog ageing test, alternate sheds silicone
rubber polymer insulator showed better contamination performance
than straight sheds silicone rubber polymer insulator. Severe surface
ageing was observed on the straight sheds insulator. The objective of
this work is to elucidate that electric field distribution along straight
sheds insulator higher than alternate shed insulator in salt fog ageing
test. Finite element method (FEM) is adopted for this work. The
simulation results confirmed the experimental data, as well.
Abstract: Recently, the health of retired National Football
League players, particularly lineman has been investigated. A
number of studies have reported increased cardiometabolic risk,
premature cardiovascular disease and incidence of type 2 diabetes.
Rugby union players have somatotypes very similar to National
Football League players which suggests that rugby players may have
similar health risks. The International Golden Oldies World Rugby
Festival (GORF) provided a unique opportunity to investigate the
demographics of veteran rugby players. METHODOLOGIES: A
cross-sectional, observational study was completed using an online
web-based questionnaire that consisted of medical history and
physiological measures. Data analysis was completed using a one
sample t-test (50yrs) and Chi-square test. RESULTS:
A total of 216 veteran rugby competitors (response rate = 6.8%)
representing 10 countries, aged 35-72 yrs (mean 51.2, S.D. ±8.0),
participated in the online survey. As a group, the incidence of current
smokers was low at 8.8% (avg 72.4 cigs/wk) whilst the percentage
consuming alcohol was high (93.1% (avg 11.2 drinks/wk).
Competitors reported the following top six chronic
diseases/disorders; hypertension (18.6%), arthritis (OA/RA, 11.5%),
asthma (9.3%), hyperlipidemia (8.2%), diabetes (all types, 7.5%) and
gout (6%), there were significant differences between groups with
regard to cancer (all types) and migraines. When compared to the
Australian general population (Australian Bureau of Statistics data,
n=18,000), GORF competitors had a significantly lower incidence of
anxiety (p
Abstract: Energy consumption rate during the cooling process
of industrial glass tempering process is considerably high. In this
experimental study the effect of dimensionless jet to jet distance
(S/D) and jet to plate distance (H/D) on the cooling time have been
investigated. In the experiments 4 mm thick glass samples have been
used. Cooling unit consists of 16 mutually placed seamless aluminum
nozzles of 8 mm in diameter and 80 mm in length. Nozzles were in
staggered arrangement. Experiments were conducted with circular
jets for H/D values between 1 and 10, and for S/D values between 2
and 10. During the experiments Reynolds number has been kept
constant at 30000. Experimental results showed that the longest
cooling time with 87 seconds has been observed in the experiments
for S/D=10 and H/D=10 values, while the shortest cooling time with
42.5 seconds has been measured in the experiments for S/D=2 and
H/D=4 values.
Abstract: The current study has investigated the ageing
phenomena of silica optical fibres in relation to water activity which might be accelerated when exposed to a supplementary energy, such as microwaves. A controlled stress by winding fibres onto accurate
diameter mandrel was applied. Taking into account that normally a
decrease in fibre strength is induced in time by chemical action of water, the effects of cumulative reagents such as: water, applied stress and supplementary energy (microwave) in some cases acted in
the opposite manner. The microwave effect as a structural relaxation
catalyst appears unexpected, even if the overall gain in fibre strength is not high, but the stress corrosion factor revealed significant
increase in certain simulation conditions.
Abstract: A slant weighted Toeplitz operator Aφ is an operator
on L2(β) defined as Aφ = WMφ where Mφ is the weighted
multiplication operator and W is an operator on L2(β) given by
We2n = βn
β2n
en, {en}n∈Z being the orthonormal basis. In this paper,
we generalise Aφ to the k-th order slant weighted Toeplitz operator
Uφ and study its properties.
Abstract: A greenhouse experiment was conducted to investigate the effects of different types of nutrients induced salinity on the growth, membrane permeability, nitrate reductase activity, proline content and macronutrient concentrations of tomato plants. The plants were subjected to six different treatments: 1 (control) containing basic solution, 2 basic solution+40mM of NaCl, 3 basic solution+40 mM of KNO3, 4 basic solution+20 mM of Ca(NO3)2.4H2O, 5 basic solution+20 mM of Mg(NO3)2.6H2O and 6 basic solution+20 mM of KNO3+5 mM of Ca(NO3)2.4H2O+5 mM of Mg(NO3)2.6H2O. Membrane permeability was increased significantly only with addition of NaCl, and then decreased to its lower level with addition of Ca(NO3)2.4H2O and Mg(NO3)2.6H2O. Proline accumulation were followed the same trend of results when they had been exposed to NaCl salinity. Nitrate reductase activity (NRA) was significantly affected by addition of different types of nutrient induced salinity.
Abstract: Utilization of diverse germplasm is needed to enhance
the genetic diversity of cultivars. The objective of this study was to
evaluate the genetic relationships of 98 alfalfa germplasm accessions
using morphological traits and SSR markers. From the 98 tested
populations, 81 were locals originating in Europe, 17 were introduced
from USA, Australia, New Zealand and Canada. Three primers
generated 67 polymorphic bands. The average polymorphic
information content (PIC) was very high (> 0.90) over all three used
primer combinations. Cluster analysis using Unweighted Pair Group
Method with Arithmetic Means (UPGMA) and Jaccard´s coefficient
grouped the accessions into 2 major clusters with 4 sub-clusters with
no correlation between genetic and morphological diversity. The SSR
analysis clearly indicated that even with three polymorphic primers,
reliable estimation of genetic diversity could be obtained.
Abstract: Based on statistics released by Islamic Republic of
Iran Police (IRIP), from among the total 9555 motorcycle accidents
that happened in 2007, 857 riders died and 11219 one got injured. If
we also consider the death toll and injuries of other vehicles'
accidents resulted from traffic violation by motorcycle riders, then
paying attention to the motorcycle accidents seems to be very
necessary. Therefore, in this study we tried to investigate the traits
and issues related to production, application, and training, along with
causes of motorcycle accidents from 4 perspectives of road, human,
environment and vehicle and also based on statistical and
geographical analysis of accident-sheets prepared by Iran Road
Patrol Department (IRPD). Unfamiliarity of riders with regulations
and techniques of motorcycling, disuse of safety equipments,
inefficiency of roads and design of junctions for safe trafficking of
motorcycles and finally the lack of sufficient control of responsible
organizations are among the major causes which lead to these
accidents.