Abstract: Application of nanoparticles as additives in membrane
synthesis for improving the resistance of membranes against fouling
has triggered recent interest in new membrane types. However, most
nanoparticle-enhanced membranes suffer from the tradeoff between
permeability and selectivity. In this study, nano-WS2 was explored as
the additive in membrane synthesis by non-solvent induced phase
separation. Blended PES-WS2 flat-sheet membranes with the
incorporation of ultra-low concentrations of nanoparticles (from 0.025
to 0.25%, WS2/PES ratio) were manufactured and investigated in
terms of permeability, fouling resistance and solute rejection.
Remarkably, a significant enhancement in the permeability was
observed as a result of the incorporation of ultra-low fractions of
nano-WS2 to the membrane structure. Optimal permeability values
were obtained for modified membranes with 0.10%
nanoparticle/polymer concentration ratios. Furthermore, fouling
resistance and solute rejection were significantly improved by the
incorporation of nanoparticles into the membrane matrix. Specifically,
fouling resistance of modified membrane can increase by around 50%.
Abstract: This work evaluated the effect of temperature on headspace solid-phase microextraction of volatile and furanic compounds in coated fish sticks. The major goal was the analysis of the samples as consumed, to reproduce volatile compounds people feel when consuming those products. Extraction at 37 ºC (the human body temperature) throughout the HS-SPME analysis of volatile and furanic compounds in coated fish was compared with higher extraction temperatures, which are frequently used for this kind of determinations. The profile of volatile compounds found in deepfried (F) and non-fried (NF) coated fish at 37 and 50 ºC was different from that obtained at 80 ºC. Concerning furan and its derivatives, an extra formation of these compounds was observed at higher extraction temperatures. The analysis of volatile and furanic compounds in fish coated sticks simulating the cooking and eating conditions can be reliably carried out setting the headspace absorption temperature at 37 ºC.
Abstract: Uterine and oviducal fluids are necessary for
capacitation of the spermatozoa and early embryonic development.
The aim of the present study was to determine the effects of estrous
cycle phases (follicular and luteal) on some biological parameters
(enzymes, electrolytes and total proteins) in uterine and oviducal
secretions of ewes. Oviducal and uterine fluids were collected,
diluted and centrifuged. According to our results, concentrations of
GPT, G6PDH, total proteins, K and Na were significantly (P
Abstract: Modeling and simulation of fixed bed three-phase
catalytic reactors are considered for wet air catalytic oxidation of
phenol to perform a comparative numerical analysis between tricklebed
and packed-bubble column reactors. The modeling involves
material balances both for the catalyst particle as well as for different
fluid phases. Catalyst deactivation is also considered in a transient
reactor model to investigate the effects of various parameters
including reactor temperature on catalyst deactivation. The
simulation results indicated that packed-bubble columns were
slightly superior in performance than trickle beds. It was also found
that reaction temperature was the most effective parameter in catalyst
deactivation.
Abstract: This paper presents a novel control strategy of a threephase
four-wire Unified Power Quality (UPQC) for an improvement
in power quality. The UPQC is realized by integration of series and
shunt active power filters (APFs) sharing a common dc bus capacitor.
The shunt APF is realized using a thee-phase, four leg voltage source
inverter (VSI) and the series APF is realized using a three-phase,
three leg VSI. A control technique based on unit vector template
technique (UTT) is used to get the reference signals for series APF,
while instantaneous sequence component theory (ISCT) is used for
the control of Shunt APF. The performance of the implemented
control algorithm is evaluated in terms of power-factor correction,
load balancing, neutral source current mitigation and mitigation of
voltage and current harmonics, voltage sag and swell in a three-phase
four-wire distribution system for different combination of linear and
non-linear loads. In this proposed control scheme of UPQC, the
current/voltage control is applied over the fundamental supply
currents/voltages instead of fast changing APFs currents/voltages,
there by reducing the computational delay and the required sensors.
MATLAB/Simulink based simulations are obtained, which support
the functionality of the UPQC. MATLAB/Simulink based
simulations are obtained, which support the functionality of the
UPQC.
Abstract: Considering non-ideal behavior of fluids and its effects on hydrodynamic and mass transfer in multiphase flow is very essential. Simulations were performed that takes into account the effects of mass transfer and mixture non-ideality on hydrodynamics reported by Irani et al. In this paper, by assuming the density of phases to be constant and Raullt-s law instead of using EOS and fugacity coefficient definition, respectively for both the liquid and gas phases, the importance of non-ideality effects on mass transfer and hydrodynamic behavior was studied. The results for a system of octane/propane (T=323 K, P =445 kpa) also indicated that the assumption of constant density in simulation had major role to diverse from experimental data. Furthermore, comparison between obtained results and the previous report indicated significant differences between experimental data and simulation results with more ideal assumptions.
Abstract: The peculiarities of the nanoscale structure-phase
states formed after electroexplosive carburizing and subsequent
electron-beam treatment of technically pure titanium surface in different regimes are established by methods of transmission electron
diffraction microscopy and physical mechanisms are discussed. Electroexplosive carburizing leads to surface layer formation
(40 m thickness) with increased (in 3.5 times) microhardness. It consists of β-titanium, graphite (monocrystals 100-150 nm,
polycrystals 5-10 nm, amorphous particles 3-5nm), TiC (5-10 nm), β-Ti02 (2-20nm). After electron-beam treatment additionally increasing the microhardness the surface layer consists of TiC.
Abstract: In this paper, a nonlinear model predictive swing-up
and stabilizing sliding controller is proposed for an inverted
pendulum-cart system. In the swing up phase, the nonlinear model
predictive control is formulated as a nonlinear programming problem
with energy based objective function. By solving this problem at
each sampling instant, a sequence of control inputs that optimize the
nonlinear objective function subject to various constraints over a
finite horizon are obtained. Then, this control drives the pendulum to
a predefined neighborhood of the upper equilibrium point, at where
sliding mode based model predictive control is used to stabilize the
systems with the specified constraints. It is shown by the simulations
that, due to the way of formulating the problem, short horizon
lengths are sufficient for attaining the swing up goal.
Abstract: In modern distributed software systems, the issue of communication among composing parts represents a critical point, but the idea of extending conventional programming languages with general purpose communication constructs seems difficult to realize. As a consequence, there is a (growing) gap between the abstraction level required by distributed applications and the concepts provided by platforms that enable communication. This work intends to discuss how the Model Driven Software Development approach can be considered as a mature technology to generate in automatic way the schematic part of applications related to communication, by providing at the same time high level specialized languages useful in all the phases of software production. To achieve the goal, a stack of languages (meta-meta¬models) has been introduced in order to describe – at different levels of abstraction – the collaborative behavior of generic entities in terms of communication actions related to a taxonomy of messages. Finally, the generation of platforms for communication is viewed as a form of specification of language semantics, that provides executable models of applications together with model-checking supports and effective runtime environments.
Abstract: A high-frequency low-power sinusoidal quadrature
oscillator is presented through the use of two 2nd-order low-pass
current-mirror (CM)-based filters, a 1st-order CM low-pass filter and
a CM bilinear transfer function. The technique is relatively simple
based on (i) inherent time constants of current mirrors, i.e. the
internal capacitances and the transconductance of a diode-connected
NMOS, (ii) a simple negative resistance RN formed by a resistor load
RL of a current mirror. Neither external capacitances nor inductances
are required. As a particular example, a 1.9-GHz, 0.45-mW, 2-V
CMOS low-pass-filter-based all-current-mirror sinusoidal quadrature
oscillator is demonstrated. The oscillation frequency (f0) is 1.9 GHz
and is current-tunable over a range of 370 MHz or 21.6 %. The
power consumption is at approximately 0.45 mW. The amplitude
matching and the quadrature phase matching are better than 0.05 dB
and 0.15°, respectively. Total harmonic distortions (THD) are less
than 0.3 %. At 2 MHz offset from the 1.9 GHz, the carrier to noise
ratio (CNR) is 90.01 dBc/Hz whilst the figure of merit called a
normalized carrier-to-noise ratio (CNRnorm) is 153.03 dBc/Hz. The
ratio of the oscillation frequency (f0) to the unity-gain frequency (fT)
of a transistor is 0.25. Comparisons to other approaches are also
included.
Abstract: Plasmodium vivax malaria differs from P. falciparum malaria in that a person suffering from P. vivax infection can suffer relapses of the disease. This is due the parasite being able to remain dormant in the liver of the patients where it is able to re-infect the patient after a passage of time. During this stage, the patient is classified as being in the dormant class. The model to describe the transmission of P. vivax malaria consists of a human population divided into four classes, the susceptible, the infected, the dormant and the recovered. The effect of a time delay on the transmission of this disease is studied. The time delay is the period in which the P. vivax parasite develops inside the mosquito (vector) before the vector becomes infectious (i.e., pass on the infection). We analyze our model by using standard dynamic modeling method. Two stable equilibrium states, a disease free state E0 and an endemic state E1, are found to be possible. It is found that the E0 state is stable when a newly defined basic reproduction number G is less than one. If G is greater than one the endemic state E1 is stable. The conditions for the endemic equilibrium state E1 to be a stable spiral node are established. For realistic values of the parameters in the model, it is found that solutions in phase space are trajectories spiraling into the endemic state. It is shown that the limit cycle and chaotic behaviors can only be achieved with unrealistic parameter values.
Abstract: This paper presents the design related to the
electronic system design of the respiratory signal, including phases
for processing, followed by the transmission and reception of this
signal and finally display. The processing of this signal is added to
the ECG and temperature sign, put up last year. Under this scheme is
proposed that in future also be conditioned blood pressure signal
under the same final printed circuit and worked.
Abstract: In this paper we present an efficient system for
independent speaker speech recognition based on neural network
approach. The proposed architecture comprises two phases: a
preprocessing phase which consists in segmental normalization and
features extraction and a classification phase which uses neural
networks based on nonparametric density estimation namely the
general regression neural network (GRNN). The relative
performances of the proposed model are compared to the similar
recognition systems based on the Multilayer Perceptron (MLP), the
Recurrent Neural Network (RNN) and the well known Discrete
Hidden Markov Model (HMM-VQ) that we have achieved also.
Experimental results obtained with Arabic digits have shown that the
use of nonparametric density estimation with an appropriate
smoothing factor (spread) improves the generalization power of the
neural network. The word error rate (WER) is reduced significantly
over the baseline HMM method. GRNN computation is a successful
alternative to the other neural network and DHMM.
Abstract: In this paper, hybrid FDMA-TDMA access technique in a cooperative distributive fashion introducing and implementing a modified protocol introduced in [1] is analyzed termed as Power and Cooperation Diversity Gain Protocol (PCDGP). A wireless network consists of two users terminal , two relays and a destination terminal equipped with two antennas. The relays are operating in amplify-and-forward (AF) mode with a fixed gain. Two operating modes: cooperation-gain mode and powergain mode are exploited from source terminals to relays, as it is working in a best channel selection scheme. Vertical BLAST (Bell Laboratories Layered Space Time) or V-BLAST with minimum mean square error (MMSE) nulling is used at the relays to perfectly detect the joint signals from multiple source terminals. The performance is analyzed using binary phase shift keying (BPSK) modulation scheme and investigated over independent and identical (i.i.d) Rayleigh, Ricean-K and Nakagami-m fading environments. Subsequently, simulation results show that the proposed scheme can provide better signal quality of uplink users in a cooperative communication system using hybrid FDMATDMA technique.
Abstract: Biologically active peptides are of particular interest
in food science and human nutrition because they have been shown to play several physiological roles. In vitro gastrointestinal digestion of lentil and whey proteins in this study produced high angiotensin-I converting enzyme inhibitory activity with 75.5±1.9 and 91.4±2.3%
inhibition, respectively. High ACE inhibitory activity was observed in lentil after 5 days of germination (84.3±1.2%). Fractionation by
reverse phase chromatography gave inhibitory activities as high as
86.3±2.0 for lentil, 94.8±1.8% for whey and 93.7±1.7% at 5th day of germination. Further purification by HPLC resulted in several
inhibitory peptides with IC50 values ranging from 0.064 to 0.164
mg/ml. These results demonstrate that lentil proteins are a good
source of peptides with ACE inhibitory activity that can be released by germination or gastrointestinal digestion. Despite the lower bioactivity in comparison with whey proteins, incorporation of lentil proteins in functional food formulations and natural drugs look promising.