Abstract: The double exponential model (DEM), or Laplace
distribution, is used in various disciplines. However, there are issues
related to the construction of confidence intervals (CI), when using
the distribution.In this paper, the properties of DEM are considered
with intention of constructing CI based on simulated data. The
analysis of pivotal equations for the models here in comparisons with
pivotal equations for normal distribution are performed, and the
results obtained from simulation data are presented.
Abstract: Nowadays, desalination of salt water is considered an important industrial process. In many parts of the world, particularly in the gulf countries, the multi-stage flash (MSF) water desalination has an essential contribution in the production of fresh water. In this study, a simple mathematical model is defined to design a MSF desalination system and the feasibility of using the MSF desalination process in proximity of a 42 MW power plant is investigated. This power plant can just provide 10 ton/h superheated steam from low pressure (LP) section of heat recovery steam generator (HRSG) for thermal desalting system. The designed MSF system with gained output ratio (GOR) of 10.3 has 24 flashing stages and can produce 2480 ton/d of fresh water. The expected performance characteristics of the designed MSF desalination plant are determined. In addition, the effect of motive water pressure on the amount of non-condensable gases removed by water jet vacuum pumps is investigated.
Abstract: Rainbow trout homogametic males, (XX or YY sex genotype), can be obtained, respectively, through masculinisation of genetic females or induced androgenesis. Aim of this study was to compare reproductive potential of neo-males (XX) and super-males (YY) with heterogametic males (XY). We measured spermatozoa motility parameters, sperm concentration, osmolality and characterized protein profiles in samples of stripped and testicular sperm obtained from XY and YY males, and testicular sperm of XX males. The motile spermatozoa, as measured by both subjective method and CASA, showed no differences between testicular sperm of XX males and stripped sperm of XY and YY males whereas testicular sperm of XY and YY males had significantly lower sperm motility. Result of protein densitometry showed similarities in protein profile between seminal plasma of XY and YY males and testicular fluids of XX males. Testis of XX males showed specific histological structures of cysts consists hypertrophied Sertoli cells.
Abstract: A mobile ad hoc network is a network of mobile nodes
without any notion of centralized administration. In such a network,
each mobile node behaves not only as a host which runs applications
but also as a router to forward packets on behalf of others. Clustering
has been applied to routing protocols to achieve efficient
communications. A CH network expresses the connected relationship
among cluster-heads. This paper discusses the methods for
constructing a CH network, and produces the following results: (1)
The required running costs of 3 traditional methods for constructing a
CH network are not so different from each other in the static
circumstance, or in the dynamic circumstance. Their running costs in
the static circumstance do not differ from their costs in the dynamic
circumstance. Meanwhile, although the routing costs required for the
above 3 methods are not so different in the static circumstance, the
costs are considerably different from each other in the dynamic
circumstance. Their routing costs in the static circumstance are also
very different from their costs in the dynamic circumstance, and the
former is one tenths of the latter. The routing cost in the dynamic
circumstance is mostly the cost for re-routing. (2) On the strength of
the above results, we discuss new 2 methods regarding whether they
are tolerable or not in the dynamic circumstance, that is, whether the
times of re-routing are small or not. These new methods are revised
methods that are based on the traditional methods. We recommended
the method which produces the smallest routing cost in the dynamic
circumstance, therefore producing the smallest total cost.
Abstract: In this paper, we proposed the direct method for converting
Finite-Impulse Response (FIR) filter with low nonzero tap
into Infinite-Impulse Response (IIR) filter using the pre-determined
table. The prony method is used by ghost cancellator which is IIR
approximation to FIR filter which is better performance than IIR and
have much larger calculation difference. The direct method for many
ghost combination with low nonzero tap of NTSC(National Television
System Committee) TV signal in Korea is described. The proposed
method is illustrated with an example.
Abstract: In this paper, a three dimensional autonomous chaotic system is considered. The existence of Hopf bifurcation is investigated by choosing the appropriate bifurcation parameter. Furthermore, formulas for determining the direction of the Hopf bifurcation and the stability of bifurcating periodic solutions are derived with the help of normal form theory. Finally, a numerical example is given.
Abstract: The purpose of this work is to establish the theoretical
foundations for calculating and designing the sublimationcondensation
processes in chemical apparatuses which are intended
for production of ultrafine powders of crystalline and amorphous
materials with controlled fractional composition. Theoretic analysis
of the primary processes of nucleation and growth kinetics of the
clusters according to the degree of super-saturation and the
homogeneous or heterogeneous nature of nucleation has been carried
out. The engineering design procedures of desublimation processes
have been offered and tested for modification of the Claus process.
Abstract: Background: Regular physical activity contributes
positively to physical and psychological health. In the present study,
the stages of change of physical activity and the total physical
Aims: The aim of this study was to investigate the proportion of
adolescent girls in each stages of change and the causative factors
associated with physical activity such as the related social support
and self efficacy in a sample of the high school students.
Methods: In this study, Social Cognitive Theory (SCT) and the
Transtheorical Model (TTM) guided instrument development. The
data regarding the demographics, psychosocial determinants of
physical activity, stage of change and physical activity was gathered
by questionnaires. Several measures of psychosocial determinants of
physical activity were translated from English into Persian using the
back-translation technique. These translated measures were
administered to 512 ninth and tenth-grade Iranian high school
students for factor analysis.
Results: The distribution of the stage of change for physical activity
was as follow: 18/5% in precontemplation, 23.4% in contemplation,
38.2% in preparation, 4.6% in action and 15.3% in maintenance.
They were in 80.1% pre-adoption stages (precontemplation stage,
contemplation stage and preparation stage) and 19.9% post-adoption
stages (action stage and maintenance stage) of physical activity.
There was a significant relate between age and physical activity in
adolescent girls (age-related decline of physical activity) p
Abstract: Quantitative Structure-Activity Relationship (QSAR)
approach for discovering novel more active Calanone derivative as
anti-leukemia compound has been conducted. There are 6
experimental activities of Calanone compounds against leukemia cell
L1210 that are used as material of the research. Calculation of
theoretical predictors (independent variables) was performed by
AM1 semiempirical method. The QSAR equation is determined by
Principle Component Regression (PCR) analysis, with Log IC50 as
dependent variable and the independent variables are atomic net
charges, dipole moment (μ), and coefficient partition of noctanol/
water (Log P). Three novel Calanone derivatives that
obtained by this research have higher activity against leukemia cell
L1210 than pure Calanone.
Abstract: We present a discussion of three adaptive filtering
algorithms well known for their one-step termination property, in
terms of their relationship with the minimal residual method. These
algorithms are the normalized least mean square (NLMS), Affine
Projection algorithm (APA) and the recursive least squares algorithm
(RLS). The NLMS is shown to be a result of the orthogonality
condition imposed on the instantaneous approximation of the Wiener
equation, while APA and RLS algorithm result from orthogonality
condition in multi-dimensional minimal residual formulation. Further
analysis of the minimal residual formulation for the RLS leads to
a triangular system which also possesses the one-step termination
property (in exact arithmetic)
Abstract: A compact 1x3 power splitter based on Photonic
Crystal Waveguides (PCW) with flexible power splitting ratio is
presented in this paper. Multimode interference coupler (MMI) is
integrated with PCW. The device size reduction compared with the
conventional MMI power splitter is attributed to the large dispersion
of the PCW. Band Solve tool is used to calculate the band structure of
PCW. Finite Difference Time Domain (FDTD) method is adopted to
simulate the relevant structure at 1550nm wavelength. The device is
polarization insensitive and allows the control of output (o/p) powers
within certain percentage points for both polarizations.
Abstract: Fuzzy controllers are potential candidates for the
control of nonlinear, time variant and also complicated systems. Anti
lock brake system (ABS) which is a nonlinear system, may not be
easily controlled by classical control methods. An intelligent Fuzzy
control method is very useful for this kind of nonlinear system. A
typical antilock brake system (ABS) by sensing the wheel lockup,
releases the brakes for a short period of time, and then reapplies again
the brakes when the wheel spins up. In this paper, an intelligent fuzzy
ABS controller is designed to adjust slipping performance for variety
of roads. There are tow major sections in the proposing control
system. First section consists of tow Fuzzy-Logic Controllers (FLC)
providing optimal brake torque for both front and rear wheels.
Second section which is also a FLC provides required amount of slip
and torque references properties for different kind of roads.
Simulation results of our proposed intelligent ABS for three different
kinds of road show more reliable and better performance in compare
with two other break systems.
Abstract: The two cart inverted pendulum system is a good
bench mark for testing the performance of system dynamics and
control engineering principles. Devasia introduced this system to
study the asymptotic tracking problem for nonlinear systems. In this
paper the problem of asymptotic tracking of the two-cart with an
inverted-pendulum system to a sinusoidal reference inputs via
introducing a novel method for solving finite-horizon nonlinear
optimal control problems is presented. In this method, an iterative
method applied to state dependent Riccati equation (SDRE) to obtain
a reliable algorithm. The superiority of this technique has been shown
by simulation and comparison with the nonlinear approach.
Abstract: The use of computer hardware and software in
education and training dates to the early 1940s, when American
researchers developed flight simulators which used analog computers
to generate simulated onboard instrument data.Computer software is
widely used to help engineers and undergraduate student solve their
problems quickly and more accurately. This paper presents the list of
computer software in geotechnical engineering.
Abstract: The selection of appropriate requirements for product
releases can make a big difference in a product success. The selection
of requirements is done by different requirements prioritization
techniques. These techniques are based on pre-defined and
systematic steps to calculate the requirements relative weight.
Prioritization is complicated by new development settings, shifting
from traditional co-located development to geographically distributed
development. Stakeholders, connected to a project, are distributed all
over the world. These geographically distributions of stakeholders
make it hard to prioritize requirements as each stakeholder have their
own perception and expectations of the requirements in a software
project. This paper discusses limitations of the Analytical Hierarchy
Process with respect to geographically distributed stakeholders-
(GDS) prioritization of requirements. This paper also provides a
solution, in the form of a modified AHP, in order to prioritize
requirements for GDS. We will conduct two experiments in this
paper and will analyze the results in order to discuss AHP limitations
with respect to GDS. The modified AHP variant is also validated in
this paper.
Abstract: The minimal condition for symmetry breaking in morphogenesis of cellular population was investigated using cellular automata based on reaction-diffusion dynamics. In particular, the study looked for the possibility of the emergence of branching structures due to mechanical interactions. The model used two types of cells an external gradient. The results showed that the external gradient influenced movement of cell type-I, also revealed that clusters formed by cells type-II worked as barrier to movement of cells type-I.
Abstract: Phytotoxicity of Daphne gnidium L. was evaluated
through the effect of incorporating leaves, stems and roots biomass
into soil (at 12.5, 25, 50g/Kg) and irrigation by their aqueous extracts
(50g/L), on the growth of two crops (Lactuca sativa L. and Raphanus
sativus L.) and two weeds (Peaganum harmala L. and Scolymus
maculatus L.). Results revealed a perceptible phytotoxic effect which
increased with dose and concentration. At the highest dose, roots and
leaves residues was the most toxic and caused total inhibition
respectively, for lettuce and thistle seedling growth. Irrigation with
aqueous extracts of D. gnidium different organs decreased also
seedlings length of all test species. Stems extract was more inhibitor
on thistle than peganum seedling growth; it induced a significant
reduction of 80% and 67%, for, respectively, roots and shoots.
Results of the present study suggest that different organs of D.
gnidium could be exploited in the management of agro-ecosystems.
Abstract: This paper proposes two types of non-isolated
direct AC-DC converters. First, it shows a buck-boost
converter with an H-bridge, which requires few components
(three switches, two diodes, one inductor and one capacitor) to
convert AC input to DC output directly. This circuit can handle
a wide range of output voltage. Second, a direct AC-DC buck
converter is proposed for lower output voltage applications.
This circuit is analyzed with output voltage of 12V. We
describe circuit topologies, operation principles and simulation
results for both circuits.
Abstract: A kind of singularly perturbed boundary value problems is under consideration. In order to obtain its approximation, simple upwind difference discretization is applied. We use a moving mesh iterative algorithm based on equi-distributing of the arc-length function of the current computed piecewise linear solution. First, a maximum norm a posteriori error estimate on an arbitrary mesh is derived using a different method from the one carried out by Chen [Advances in Computational Mathematics, 24(1-4) (2006), 197-212.]. Then, basing on the properties of discrete Green-s function and the presented posteriori error estimate, we theoretically prove that the discrete solutions computed by the algorithm are first-order uniformly convergent with respect to the perturbation parameter ε.
Abstract: High Strength Concrete (HSC) is defined as concrete
that meets special combination of performance and uniformity
requirements that cannot be achieved routinely using conventional
constituents and normal mixing, placing, and curing procedures. It is
a highly complex material, which makes modeling its behavior a very
difficult task. This paper aimed to show possible applicability of
Neural Networks (NN) to predict the slump in High Strength
Concrete (HSC). Neural Network models is constructed, trained and
tested using the available test data of 349 different concrete mix
designs of High Strength Concrete (HSC) gathered from a particular
Ready Mix Concrete (RMC) batching plant. The most versatile
Neural Network model is selected to predict the slump in concrete.
The data used in the Neural Network models are arranged in a format
of eight input parameters that cover the Cement, Fly Ash, Sand,
Coarse Aggregate (10 mm), Coarse Aggregate (20 mm), Water,
Super-Plasticizer and Water/Binder ratio. Furthermore, to test the
accuracy for predicting slump in concrete, the final selected model is
further used to test the data of 40 different concrete mix designs of
High Strength Concrete (HSC) taken from the other batching plant.
The results are compared on the basis of error function (or
performance function).