Abstract: We describe an effective method for image encryption
which employs magnitude and phase manipulation using carrier
images. Although it involves traditional methods like magnitude and
phase encryptions, the novelty of this work lies in deploying the
concept of carrier images for encryption purpose. To this end, a
carrier image is randomly chosen from a set of stored images. One
dimensional (1-D) discrete Fourier transform (DFT) is then carried
out on the original image to be encrypted along with the carrier
image. Row wise spectral addition and scaling is performed between
the magnitude spectra of the original and carrier images by randomly
selecting the rows. Similarly, row wise phase addition and scaling is
performed between the original and carrier images phase spectra by
randomly selecting the rows. The encrypted image obtained by these
two operations is further subjected to one more level of magnitude
and phase manipulation using another randomly chosen carrier image
by 1-D DFT along the columns. The resulting encrypted image is
found to be fully distorted, resulting in increasing the robustness
of the proposed work. Further, applying the reverse process at the
receiver, the decrypted image is found to be distortionless.
Abstract: A nonlinear model of two-beam free-electron laser
(FEL) in the absence of slippage is presented. The two beams are
assumed to be cold with different energies and the fundamental
resonance of the higher energy beam is at the third harmonic of lower
energy beam. By using Maxwell-s equations and full Lorentz force
equations of motion for the electron beams, coupled differential
equations are derived and solved numerically by the fourth order
Runge–Kutta method. In this method a considerable growth of third
harmonic electromagnetic field in the XUV and X-ray regions is
predicted.
Abstract: Bio-electrical responses obtained from freshwater
sediments by employing microbial fuel cell (MFC) technology were
investigated in this experimental study. During the electricity
generation, organic matter in the sediment was microbially oxidized
under anaerobic conditions with an electrode serving as a terminal
electron acceptor. It was found that the sediment organic matter
(SOM) associated with electrochemically-active electrodes became
more humified, aromatic, and polydispersed, and had a higher average
molecular weight, together with the decrease in the quantity of SOM.
The alteration of characteristics of the SOM was analogous to that
commonly observed in the early stage of SOM diagenetic process (i.e.,
humification). These findings including an elevation of the sediment
redox potential present a possibility of the MFC technology as a new
soil/sediment remediation technique based on its potential benefits:
non-destructive electricity generation and bioremediation.
Abstract: The present study was carried out to evaluate the
nutritional value of sorghum flour during processing of injera
(unleavened thick bread). The proximate composition of sorghum
flour before and after fermentation and that of injera was determined.
Compared to the raw flour and fermented one, injera had low protein
(11.55%), ash (1.57%) and fat (2.40%) contents but high in fiber
content. Moreover, injera was found to have significantly (P ≤ 0.05)
higher energy (389.08 Kcal/100g) compared to raw and fermented
sorghum flour. Injera contained lower levels of anti-nutritional
factors (polyphenols, phytate and tannins) compared to raw and
fermented sorghum. Also it was found to be rich in Ca
(4.75mg/100g), Fe (3.95 mg/100g), and Cu (0.7 mg/100g) compared
to that of raw and fermented flour. Moreover, both the extractable
minerals and protein digestibility were high for injera due to low
amount of anti-nutrients. Injera was found to contain an appreciable
amount of amino acids except arginine and tyrosine.
Abstract: The effect of cross linking of the protein isolates of
three legumes with the microbial enzyme transglutaminase (EC
2.3.2.13) on the functional properties at different NaCl concentration
was studied. The reduction in the total free amino groups (OD340) of
the polymerized protein showed that TGase treatment cross-linking
the protein subunit of each legume. The solubility of the protein
polymer of each legume was greatly improved at high concentration
of NaCl. At 1.2 M NaCl the solubility of the native legumes protein
was significantly decreased but after polymerization slightly
improved. Cross linked proteins were less turbid on heating to higher
temperature as compared to native proteins and the temperature at
which the protein turns turbid also increased in the polymerized
proteins. The emulsifying and foaming properties of the protein
polymer were greatly improved at all concentrations of NaCl for all
legumes.
Abstract: The studying of enzymatic esterification of carboxylic
acids and higher alcohols was performed by esterase Saccharomyces
cerevisiae in water-organic medium. Investigation of the enzyme
specificity to acetic substrates showed the best result with acetic acid
in esterification reactions with ethanol whereas within other
carboxylic acids the esterification decreased with acids: hexanoic >
pentanoic > butyric > decanoic. In relation to higher alcohols C3-C5,
esterification increased with alcohols propanol < butanol < amylol.
Also it was determined that esterase was more specific to alcohols
with branched chain such as isobutyl alcohol and isoamyl alcohol.
Data obtained may have important practical implications, for
example, for application of yeast esterase in producing various
volatile esters as well as in enzymatic transformation of volatile acids
and toxic fusel alcohols into volatile esters by providing the
production of the high quality alcoholic beverages with redused
content of higher alcohols as well as with improved degustational and
hygienic properties.
Abstract: This paper presents a novel three-phase utility
frequency to high frequency soft switching power conversion circuit
with dual mode pulse width modulation and pulse density modulation
for high power induction heating applications as melting of steel and
non ferrous metals, annealing of metals, surface hardening of steel
and cast iron work pieces and hot water producers, steamers and
super heated steamers. This high frequency power conversion circuit
can operate from three-phase systems to produce high current for
high power induction heating applications under the principles of
ZVS and it can regulate its ac output power from the rated value to a
low power level. A dual mode modulation control scheme based on
high frequency PWM in synchronization with the utility frequency
positive and negative half cycles for the proposed high frequency
conversion circuit and utility frequency pulse density modulation is
produced to extend its soft switching operating range for wide ac
output power regulation. A dual packs heat exchanger assembly is
designed to be used in consumer and industrial fluid pipeline systems
and it is proved to be suitable for the hot water, steam and super
heated steam producers. Experiment and simulation results are given
in this paper to verify the operation principles of the proposed ac
conversion circuit and to evaluate its power regulation and
conversion efficiency. Also, the paper presents a mutual coupling
model of the induction heating load instead of equivalent transformer
circuit model.
Abstract: Quality of school meals is one of the major concerns of governments and international organizations worldwide. This study aims to evaluate nutritional compliance of meals served at a Portuguese primary school considering the portions stated by Portuguese Education Ministry. To evaluate adequacy of portions served, weighing of all meal components offered to students and leftovers was performed during ten consecutive days at two different moments. Plate waste (%) was calculated by the ratio of food discarded and food served to the children. Nutritional evaluation of menus was made using the Portuguese Food Composition Table. Meals evaluated showed a percent contribution to energetic daily intake higher than recommendations. Meals served to children were considered high energy and protein dense. No significant waste of soup was accounted and the main meal components wasted were fish and vegetables. It will be necessary to adjust portions indicated by Ministry of Education in order to comply with recommendations and reduce food waste.
Abstract: In the current decade, wireless sensor networks are
emerging as a peculiar multi-disciplinary research area. By this
way, energy efficiency is one of the fundamental research themes
in the design of Medium Access Control (MAC) protocols for
wireless sensor networks. Thus, in order to optimize the energy
consumption in these networks, a variety of MAC protocols are
available in the literature. These schemes were commonly evaluated
under simple network density and a few results are published on
their robustness in realistic network-s size. We, in this paper, provide
an analytical study aiming to highlight the energy waste sources in
wireless sensor networks. Then, we experiment three energy efficient
hybrid CSMA/CA based MAC protocols optimized for wireless
sensor networks: Sensor-MAC (SMAC), Time-out MAC (TMAC)
and Traffic aware Energy Efficient MAC (TEEM). We investigate
these protocols with different network densities in order to discuss
the end-to-end performances of these schemes (i.e. in terms of energy
efficiency, delay and throughput). Through Network Simulator (NS-
2) implementations, we explore the behaviors of these protocols with
respect to the network density. In fact, this study may help the multihops
sensor networks designers to design or select the MAC layer
which matches better their applications aims.
Abstract: In many ways, biomedical analysis is analogous to possibilistic reasoning. In spite of that, there are hardly any applications of possibility theory in biology or medicine. The aim of this work is to demonstrate the use of possibility theory in an epidemiological study. In the paper, we build the possibility distribution for the controlled bloodstream concentrations of any physiologically active substance through few approximate considerations. This possibility distribution is tested later against the empirical histograms obtained from the panel study of the eight different physiologically active substances in 417 individuals.
Abstract: Palm methyl ester (PME) is one of the alternative
biomass fuels to liquid fossil fuels. To investigate the combustion
characteristics of PME as an alternative fuel for gas turbines, combustion experiments using two types of burners under atmospheric
pressure were performed. One of the burners has a configuration
making strong non-premixed flame, whereas the other has a
configuration promoting prevaporization of fuel droplets. The results
show that the NOx emissions can be reduced by employing the latter burner without accumulation of soot when PME is used as a fuel. A
burner configuration promoting prevaporzation of fuel droplets is
recommended for PME.
Abstract: The success of an electronic system in a System-on- Chip is highly dependent on the efficiency of its interconnection network, which is constructed from routers and channels (the routers move data across the channels between nodes). Since neither classical bus based nor point to point architectures can provide scalable solutions and satisfy the tight power and performance requirements of future applications, the Network-on-Chip (NoC) approach has recently been proposed as a promising solution. Indeed, in contrast to the traditional solutions, the NoC approach can provide large bandwidth with moderate area overhead. The selected topology of the components interconnects plays prime rule in the performance of NoC architecture as well as routing and switching techniques that can be used. In this paper, we present two generic NoC architectures that can be customized to the specific communication needs of an application in order to reduce the area with minimal degradation of the latency of the system. An experimental study is performed to compare these structures with basic NoC topologies represented by 2D mesh, Butterfly-Fat Tree (BFT) and SPIN. It is shown that Cluster mesh (CMesh) and MinRoot schemes achieves significant improvements in network latency and energy consumption with only negligible area overhead and complexity over existing architectures. In fact, in the case of basic NoC topologies, CMesh and MinRoot schemes provides substantial savings in area as well, because they requires fewer routers. The simulation results show that CMesh and MinRoot networks outperforms MESH, BFT and SPIN in main performance metrics.
Abstract: This article discusses the problem of estimating the
orientation of inclined ground on which a human subject stands based
on information provided by the vestibular system consisting of the
otolith and semicircular canals. It is assumed that body segments are
not necessarily aligned and thus forming an open kinematic chain.
The semicircular canals analogues to a technical gyrometer provide a
measure of the angular velocity whereas the otolith analogues to a
technical accelerometer provide a measure of the translational
acceleration. Two solutions are proposed and discussed. The first is
based on a stand-alone Kalman filter that optimally fuses the two
measurements based on their dynamic characteristics and their noise
properties. In this case, no body dynamic model is needed. In the
second solution, a central extended disturbance observer that
incorporates a body dynamic model (internal model) is employed.
The merits of both solutions are discussed and demonstrated by
experimental and simulation results.
Abstract: Constant amplitude fatigue crack growth (FCG) tests
were performed on dissimilar metal welded plates of Type 316L
Stainless Steel (SS) and IS 2062 Grade A Carbon steel (CS). The
plates were welded by TIG welding using SS E309 as electrode. FCG
tests were carried on the Side Edge Notch Tension (SENT)
specimens of 5 mm thickness, with crack initiator (notch) at base
metal region (BM), weld metal region (WM) and heat affected zones
(HAZ). The tests were performed at a test frequency of 10 Hz and at
load ratios (R) of 0.1 & 0.6. FCG rate was found to increase with
stress ratio for weld metals and base metals, where as in case of
HAZ, FCG rates were almost equal at high ΔK. FCG rate of HAZ of
stainless steel was found to be lowest at low and high ΔK. At
intermediate ΔK, WM showed the lowest FCG rate. CS showed
higher crack growth rate at all ΔK. However, the scatter band of data
was found to be narrow. Fracture toughness (Kc) was found to vary
in different locations of weldments. Kc was found lowest for the
weldment and highest for HAZ of stainless steel. A novel method of
characterizing the FCG behavior using an Infrared thermography
(IRT) camera was attempted. By monitoring the temperature rise at
the fast moving crack tip region, the amount of plastic deformation
was estimated.
Abstract: Acute toxicity of nano SiO2, ZnO, MCM-41 (Meso
pore silica), Cu, Multi Wall Carbon Nano Tube (MWCNT), Single
Wall Carbon Nano Tube (SWCNT) , Fe (Coated) to bacteria Vibrio
fischeri using a homemade luminometer , was evaluated. The values
of the nominal effective concentrations (EC), causing 20% and 50%
inhibition of biouminescence, using two mathematical models at two
times of 5 and 30 minutes were calculated. Luminometer was
designed with Photomultiplier (PMT) detector. Luminol
chemiluminescence reaction was carried out for the calibration graph.
In the linear calibration range, the correlation coefficients and
coefficient of Variation (CV) were 0.988 and 3.21% respectively
which demonstrate the accuracy and reproducibility of the instrument
that are suitable. The important part of this research depends on how
to optimize the best condition for maximum bioluminescence. The
culture of Vibrio fischeri with optimal conditions in liquid media,
were stirring at 120 rpm at a temperature of 150C to 180C and were
incubated for 24 to 72 hours while solid medium was held at 180C
and for 48 hours. Suspension of nanoparticles ZnO, after 30 min
contact time to bacteria Vibrio fischeri, showed the highest toxicity
while SiO2 nanoparticles showed the lowest toxicity. After 5 min
exposure time, the toxicity of ZnO was the strongest and MCM-41
was the weakest toxicant component.
Abstract: The aim of this study was to analyse the most
important parameters determining the quality of the motion structure
of the basic classical dance jump – grand jeté.Research sample
consisted of 8 students of the Dance Conservatory in Brno. Using the
system Simi motion we performed a 3D kinematic analysis of the
jump. On the basis of the comparison of structure quality and
measured data of the grand jeté, we defined the optimal values of the
relevant parameters determining the quality of the performance. The
take-off speed should achieve about 2.4 m·s-1, the optimum take-off
angle is 28 - 30º. The take-off leg should swing backward at the
beginning of the flight phase with the minimum speed of 3.3 m·s-1.If
motor abilities of dancers achieve the level necessary for optimal
performance of a classical dance jump, there is room for certain
variability of the structure of the dance jump.
Abstract: Inflammatory bowel disease (IBD) is a chronic
relapsing-remitting condition that afflicts millions of people
throughout the world and impairs their daily functions and quality of
life. Treatment of IBD depends largely on 5-aminosalicylic acid (5-
ASA) and corticosteroids. The present study aimed to clarify the
effects of 5-aminosalicylic acid, budesonide and currcumin on 90
male albino rats against trinitrobenzene sulfonic acid (TNB) induced
colitis. TNB was injected intrarectally to 50 rats. The other 40 rats
served as control groups. Both 5-ASA (in a dose of 120 mg/kg) and
budesonide (in a dose of 0.1 mg/kg) were administered daily for one
week whereas currcumin was injected intraperitonially (in a dose of
30 mg/kg daily) for 14 days after injection of either TNB in the
colitis rats (group B) or saline in control groups (group A). The study
included estimation of macroscopic score index, histological
examination of H&E stained sections of the colonic tissue,
biochemical estimation of myeloperoxidase (MPO), nitric oxide
(NO), and caspase-3 levels, in addition to studying the effect of tested
drugs on colonic motility. It was found that budesonide and curcumin
improved mucosal healing, reduced both NO production and caspase-
3 level. They had the best impact on the disturbed colonic motility in
TNBS-model of colitis.
Abstract: The sequential morphologic changes of rabbit duodenal mucosa-submucosa were studied from primodial stage to birth in 15 fetuses and during the early days of life in 21 rabbit newborns till maturity using light, scanning and transmission electron microscopy. Fetal rabbit duodenum develops from a simple tube of stratified epithelium to a tube containing villus and intervillus regions of simple columnar epithelium. By day 21 of gestation, the first rudimentary villi were appeared and by day 24 the first true villi were appeared. The Crypts of Lieberkuhn did not appear until birth. By the first day of postnatal life the duodenal glands appeared. The histological maturity of the rabbit small intestine occurred one month after birth. In conclusion, at all stages, the sequential morphologic changes of the rabbit small intestine developed to meet the structural and physiological demands during the fetal stage to be prepared to extra uterine life.
Abstract: Use of microemulsion in enhanced oil recovery has become more attractive in recent years because of its high level of extraction efficiency. Experimental investigations have been made on characterization of microemulsions of oil-brinesurfactant/ cosurfactant system for its use in enhanced oil recovery (EOR). Sodium dodecyl sulfate, propan-1-ol and heptane were selected as surfactant, cosurfactant and oil respectively for preparation of microemulsion. The effects of salinity on the relative phase volumes and solubilization parameters have also been studied. As salinity changes from low to high value, phase transition takes place from Winsor I to Winsor II via Winsor III. Suitable microemulsion composition has been selected based on its stability and ability to reduce interfacial tension. A series of flooding experiments have been performed using the selected microemulsion. The flooding experiments were performed in a core flooding apparatus using uniform sand pack. The core holder was tightly packed with uniform sands (60-100 mesh) and saturated with brines of different salinities. It was flooded with the brine at 25 psig and the absolute permeability was calculated from the flow rate of the through sand pack. The sand pack was then flooded with the crude oil at 800 psig to irreducible water saturation. The initial water saturation was determined on the basis of mass balance. Waterflooding was conducted by placing the coreholder horizontally at a constant injection pressure at 200 pisg. After water flooding, when water-cut reached above 95%, around 0.5 pore volume (PV) of the above microemulsion slug was injected followed by chasing water. The experiments were repeated using different composition of microemulsion slug. The additional recoveries were calculated by material balance. Encouraging results with additional recovery more than 20% of original oil in place above the conventional water flooding have been observed.
Abstract: Biodiversity crisis is one of the many crises that
started at the turn of the millennia. Concrete form of expression is
still disputed, but there is a relatively high consensus regarding the
high rate of degradation and the urgent need for action. The strategy
of action outlines a strong economic component, together with the
recognition of market mechanisms as the most effective policies to
protect biodiversity. In this context, biodiversity and ecosystem
services are natural assets that play a key role in economic strategies
and technological development to promote development and
prosperity. Developing and strengthening policies for transition to an
economy based on efficient use of resources is the way forward.
To emphasize the co-viability specific to the connection economyecosystem
services, scientific approach aimed on one hand how to
implement policies for nature conservation and on the other hand, the
concepts underlying the economic expression of ecosystem services-
value, in the context of current technology. Following the analysis of
business opportunities associated with changes in ecosystem services
was concluded that development of market mechanisms for nature
conservation is a trend that is increasingly stronger individualized
within recent years. Although there are still many controversial issues
that have already given rise to an obvious bias, international
organizations and national governments have initiated and
implemented in cooperation or independently such mechanisms.
Consequently, they created the conditions for convergence between
private interests and social interests of nature conservation, so there
are opportunities for ongoing business development which leads,
among other things, the positive effects on biodiversity. Finally,
points out that markets fail to quantify the value of most ecosystem
services. Existing price signals reflect at best, only a proportion of the
total amount corresponding provision of food, water or fuel.