Abstract: In developing a text-to-speech system, it is well
known that the accuracy of information extracted from a text is
crucial to produce high quality synthesized speech. In this paper, a
new scheme for converting text into its equivalent phonetic spelling
is introduced and developed. This method is applicable to many
applications in text to speech converting systems and has many
advantages over other methods. The proposed method can also
complement the other methods with a purpose of improving their
performance. The proposed method is a probabilistic model and is
based on Smooth Ergodic Hidden Markov Model. This model can be
considered as an extension to HMM. The proposed method is applied
to Persian language and its accuracy in converting text to speech
phonetics is evaluated using simulations.
Abstract: Dual phase steels (DPS)s have a microstructure
consisting of a hard second phase called Martensite in the soft Ferrite
matrix. In recent years, there has been interest in dual-phase steels,
because the application of these materials has made significant usage;
particularly in the automotive sector Composite microstructure of
(DPS)s exhibit interesting characteristic mechanical properties such
as continuous yielding, low yield stress to tensile strength
ratios(YS/UTS), and relatively high formability; which offer
advantages compared with conventional high strength low alloy
steels(HSLAS). The research dealt with the characterization of
damage in (DPS)s. In this study by review the mechanisms of failure
due to volume fraction of martensite second phase; a new method is
introduced to identifying the mechanisms of failure in the various
phases of these types of steels. In this method the acoustic emission
(AE) technique was used to detect damage progression. These failure
mechanisms consist of Ferrite-Martensite interface decohesion and/or
martensite phase fracture. For this aim, dual phase steels with
different volume fraction of martensite second phase has provided by
various heat treatment methods on a low carbon steel (0.1% C), and
then AE monitoring is used during tensile test of these DPSs. From
AE measurements and an energy ratio curve elaborated from the
value of AE energy (it was obtained as the ratio between the strain
energy to the acoustic energy), that allows detecting important
events, corresponding to the sudden drops. These AE signals events
associated with various failure mechanisms are classified for ferrite
and (DPS)s with various amount of Vm and different martensite
morphology. It is found that AE energy increase with increasing Vm.
This increasing of AE energy is because of more contribution of
martensite fracture in the failure of samples with higher Vm. Final
results show a good relationship between the AE signals and the
mechanisms of failure.
Abstract: Injection forging is a Nett-shape manufacturing
process in which one or two punches move axially causing a radial
flow into a die cavity in a form which is prescribed by the exitgeometry,
such as pulley, flanges, gears and splines on a shaft. This
paper presents an experimental and numerical study of the injection
forging of splines in terms of load requirement and material flow.
Three dimensional finite element analyses are used to investigate the
effect of some important parameters in this process. The experiment
has been carried out using solid commercial lead billets with two
different billet diameters and four different dies.
Abstract: One of the most important requirements for the
operation and planning activities of an electrical utility is the
prediction of load for the next hour to several days out, known as
short term load forecasting. This paper presents the development of
an artificial neural network based short-term load forecasting model.
The model can forecast daily load profiles with a load time of one
day for next 24 hours. In this method can divide days of year with
using average temperature. Groups make according linearity rate of
curve. Ultimate forecast for each group obtain with considering
weekday and weekend. This paper investigates effects of temperature
and humidity on consuming curve. For forecasting load curve of
holidays at first forecast pick and valley and then the neural network
forecast is re-shaped with the new data. The ANN-based load models
are trained using hourly historical. Load data and daily historical
max/min temperature and humidity data. The results of testing the
system on data from Yazd utility are reported.
Abstract: This paper presents the applicability of artificial
neural networks for 24 hour ahead solar power generation forecasting
of a 20 kW photovoltaic system, the developed forecasting is suitable
for a reliable Microgrid energy management. In total four neural
networks were proposed, namely: multi-layred perceptron, radial
basis function, recurrent and a neural network ensemble consisting in
ensemble of bagged networks. Forecasting reliability of the proposed
neural networks was carried out in terms forecasting error
performance basing on statistical and graphical methods. The
experimental results showed that all the proposed networks achieved
an acceptable forecasting accuracy. In term of comparison the neural
network ensemble gives the highest precision forecasting comparing
to the conventional networks. In fact, each network of the ensemble
over-fits to some extent and leads to a diversity which enhances the
noise tolerance and the forecasting generalization performance
comparing to the conventional networks.
Abstract: For the efficient and safe use of the cable-stayed
bridge, a design based on the detailed local analysis of the cable anchor
system is required. Also, a theoretical design process for the anchor
system should be prepared and reviewed. Generally, the size of the
fixing pipe in the anchor system is decided according to the
specifications prepared by cable-manufacturing companies, and
accordingly, there is difficulty determining the initial inner diameters
of the fixing pipes. As such, there is no choice but to use the products
with the existing sizes. In this study, the existing design process of the
fixing pipe, is a type of guide pipe anchor in the cable anchor system,
is reviewed, a formula determining the thickness of the fixing pipe is
proposed, and the convenience and validity of the suggested equation
is compared with the results of the existing designs to verify its
convenience and validity.
Abstract: Aluminothermic rail welding was from the beginning
a great success because its low price even in 1895 in Germany. This
method is now, widely used all over the world for the railways
construction, maintenance and modernization. Instructions give you
guidelines for preparing papers for conferences or journals.
After 1989, the welding needs of the potentials beneficiaries
(Romanian Railways, Urban Transportation Companies) keep raise
because of the railways maintenance and modernization necessity.
The main materials that determine the Thermit (T) composition
result from manufacturing scraps all over the country. This can help
the environment by consuming these scraps.
The Romanian need for alumino-thermic welding is now by 11300
per year, and in a favourable economical environment, this amount
can reach 30000 units.
This paper tries to show the effect of two types of modifiers
introduced in the T composition on the structure and properties of an
alumino-thermic welding.
Abstract: In this paper, a new approach for design of a fully
differential second order current mode continuous-time sigma-delta
modulator is presented. For circuit implementation, square root
domain (SRD) translinear loop based on floating-gate MOS
transistors that operate in saturation region is employed. The
modulator features, low supply voltage, low power consumption
(8mW) and high dynamic range (55dB). Simulation results confirm
that this design is suitable for data converters.
Abstract: Attitude control of aerospace system with liquid containers may face to a problem associate with fuel sloshing. The sloshing phenomena can degrade the stability of control system and in the worst case, interaction between the attitude control system and fuel vibration leading to resonance. In this paper, a full process of nonlinear dynamic modeling of an aerospace launch vehicle with fuel sloshing is given. Then, a new control system based on model reference adaptive filter is proposed and its algorithm is extracted. This controller implemented on the main attitude control system. Finally, numerical simulation of nonlinear model and control system is carried out to examine the performance of the new controller. Results of simulations show that the inconvenient effects of the fuel sloshing by augmenting this control system are reduced and attitude control system performs, satisfactorily.
Abstract: The flow and heat transfer mechanism in convex
corrugated tubes have been investigated through numerical
simulations in this paper. Two kinds of tube types named as symmetric
corrugated tube (SCT) and asymmetric corrugated tube (ACT) are
modeled and studied numerically based on the RST model. The
predictive capability of RST model is examined in the corrugation wall
in order to check the reliability of RST model under the corrugation
wall condition. We propose a comparison between the RST modelling
the corrugation wall with existing direct numerical simulation of Maaß
C and Schumann U [14]. The numerical results pressure coefficient at
different profiles between RST and DNS are well matched. The
influences of large corrugation tough radii to heat transfer and flow
characteristic had been considered. Flow and heat transfer comparison
between SCT and ACT had been discussed. The numerical results
show that ACT exhibits higher overall heat transfer performance than
SCT.
Abstract: Simultaneous effects of temperature, immersion time, salt concentration, sucrose concentration, pressure and convective dryer temperature on the combined osmotic dehydration - convective drying of edible button mushrooms were investigated. Experiments were designed according to Central Composite Design with six factors each at five different levels. Response Surface Methodology (RSM) was used to determine the optimum processing conditions that yield maximum water loss and rehydration ratio and minimum solid gain and shrinkage in osmotic-convective drying of edible button mushrooms. Applying surfaces profiler and contour plots optimum operation conditions were found to be temperature of 39 °C, immersion time of 164 min, salt concentration of 14%, sucrose concentration of 53%, pressure of 600 mbar and drying temperature of 40 °C. At these optimum conditions, water loss, solid gain, rehydration ratio and shrinkage were found to be 63.38 (g/100 g initial sample), 3.17 (g/100 g initial sample), 2.26 and 7.15%, respectively.
Abstract: A methodology to design a nonlinear observer in a
bond graph approach is proposed. The class of nonlinear observer
with multivariable nonlinearities is considered. A junction structure
of the bond graph observer is proposed. The proposed methodology
to an electrical transformer and a DC motor including the nonlinear
saturation is applied. Nonlinear observers for the transformer and DC
motor based on multivariable circle criterion in the physical domain
are proposed. In order to show the saturation effects on the
transformer and DC motor, simulation results are obtained. Finally,
the paper describes that convergence of the estimates to the true
states is achieved.
Abstract: Dorsal hand vein pattern is an emerging biometric which is attracting the attention of researchers, of late. Research is being carried out on existing techniques in the hope of improving them or finding more efficient ones. In this work, Principle Component Analysis (PCA) , which is a successful method, originally applied on face biometric is being modified using Cholesky decomposition and Lanczos algorithm to extract the dorsal hand vein features. This modified technique decreases the number of computation and hence decreases the processing time. The eigenveins were successfully computed and projected onto the vein space. The system was tested on a database of 200 images and using a threshold value of 0.9 to obtain the False Acceptance Rate (FAR) and False Rejection Rate (FRR). This modified algorithm is desirable when developing biometric security system since it significantly decreases the matching time.
Abstract: Dispersions of casein micelles (CM) were studied at a
constant protein concentration of 5 wt % in high NaCl environment
ranging from 0% to 12% by Dynamic light scattering (DLS) and
Fourier Transform Infrared (FTIR). The rehydration profiles obtained
were interpreted in term of wetting, swelling and dispersion stages by
using a turbidity method. Two behaviours were observed depending
on the salt concentration. The first behaviour (low salt concentration)
presents a typical rehydration profile with a significant change
between 3 and 6% NaCl indicating quick wetting, swelling and long
dispersion stage. On the opposite, the dispersion stage of the second
behaviour (high salt concentration) was significantly shortened
indicating a strong modification of the protein backbone. A salt
increase result to a destabilization of the micelle and the formation of
mini-micelles more or less aggregated indicating an average micelles
size ranging from 100 to 200 nm. For the first time, the estimations
of secondary structural elements (irregular, ß-sheet, α-helix and turn)
by the Amide III assignments were correlated with results from
Amide I.
Abstract: This paper presents preliminary results regarding system-level power awareness for FPGA implementations in wireless sensor networks. Re-configurability of field programmable gate arrays (FPGA) allows for significant flexibility in its applications to embedded systems. However, high power consumption in FPGA becomes a significant factor in design considerations. We present several ideas and their experimental verifications on how to optimize power consumption at high level of designing process while maintaining the same energy per operation (low-level methods can be used additionally). This paper demonstrates that it is possible to estimate feasible power consumption savings even at the high level of designing process. It is envisaged that our results can be also applied to other embedded systems applications, not limited to FPGA-based.
Abstract: Water leakage is a serious problem in the maintenance of a waterworks facility. Monitoring the water flow rate is one way to locate leakage. However, conventional flowmeters such as the wet-type flowmeter and the clamp-on type ultrasonic flowmeter require additional construction for their installation and are therefore quite expensive. This paper proposes a novel estimation system for the flow rate in a water pipeline, which employs a vibration sensor. This assembly can be attached to any water pipeline without the need for additional high-cost construction. The vibration sensor is designed based on a condenser microphone. This sensor detects vibration caused by water flowing through a pipeline. It is possible to estimate the water flow rate by measuring the amplitude of the output signal from the vibration sensor. We confirmed the validity of the proposed sensing system experimentally.
Abstract: In this paper, a Markovian risk model with two-type claims is considered. In such a risk model, the occurrences of the two type claims are described by two point processes {Ni(t), t ¸ 0}, i = 1, 2, where {Ni(t), t ¸ 0} is the number of jumps during the interval (0, t] for the Markov jump process {Xi(t), t ¸ 0} . The ruin probability ª(u) of a company facing such a risk model is mainly discussed. An integral equation satisfied by the ruin probability ª(u) is obtained and the bounds for the convergence rate of the ruin probability ª(u) are given by using key-renewal theorem.
Abstract: The energy consumption and delay in read/write
operation of conventional SRAM is investigated analytically as well
as by simulation. Explicit analytical expressions for the energy
consumption and delay in read and write operation as a function of
device parameters and supply voltage are derived. The expressions are
useful in predicting the effect of parameter changes on the energy
consumption and speed as well as in optimizing the design of
conventional SRAM. HSPICE simulation in standard 0.25μm CMOS
technology confirms precision of analytical expressions derived from
this paper.
Abstract: The objective of this research is to examine the shear thinning behaviour of mixing flow of non-Newtonian fluid like toothpaste in the dissolution container with rotating stirrer. The problem under investigation is related to the chemical industry. Mixing of fluid is performed in a cylindrical container with rotating stirrer, where stirrer is eccentrically placed on the lid of the container. For the simulation purpose the associated motion of the fluid is considered as revolving of the container, with stick stirrer. For numerical prediction, a time-stepping finite element algorithm in a cylindrical polar coordinate system is adopted based on semi-implicit Taylor-Galerkin/pressure-correction scheme. Numerical solutions are obtained for non-Newtonian fluids employing power law model. Variations with power law index have been analysed, with respect to the flow structure and pressure drop.
Abstract: There is growing interest in biodiesel (fatty acid
methyl ester or FAME) because of the similarity in its properties
when compared to those of diesel fuels. Diesel engines operated on
biodiesel have lower emissions of carbon monoxide, unburned
hydrocarbons, particulate matter, and air toxics than when operated
on petroleum-based diesel fuel. Production of fatty acid methyl ester
(FAME) from rapeseed (nonedible oil) fatty acid distillate having
high free fatty acids (FFA) was investigated in this work. Conditions
for esterification process of rapeseed oil were 1.8 % H2SO4 as
catalyst, MeOH/oil of molar ratio 2 : 0.1 and reaction temperature
65 °C, for a period of 3h. The yield of methyl ester was > 90 % in 1
h.
The amount of FFA was reduced from 93 wt % to less than 2 wt %
at the end of the esterification process. The FAME was pureed by
neutralization with 1 M sodium hydroxide in water solution at a
reaction temperature of 62 °C. The final FAME product met with the
biodiesel quality standard, and ASTM D 6751.