Abstract: Contracting authorities in the public sector are
obligated to apply the principles provided for in the Polish law for the
evaluation and selection of contractors. In order to analyse the
methods of contractors selecting applied in practice by public clients,
the notices of contract award results for construction works were
analysed. The analysis shows that the procedure selected more and
more often is open competitive bidding, where the assessment of the
competence of contractors is not very precise, as well as noncompetitive
bidding, i.e. single source procurement. The share of
procurement procedures, where the only criterion is price, is
increasing. The solution to the problems existing here might be the
introduction of one of the forms of pre-selection of contractors. The
article also briefly discusses verification systems for companies
applying for public contracts used in EU countries.
Abstract: Complexation of anthocyanins to mimic natural
copigmentation process was investigated. Cyanidin-rich extracts from
Zea mays L. ceritina Kulesh. and delphinidin-rich extracts from
Clitoria ternatea L. were used to form 4 anthocyanin complexes,
AC1, AC2, AC3 and AC4, in the presence of several polyphenols and
a trace metal. Characterizations of the ACs were conducted by UV,
FTIR, DSC/TGA and morphological observations. Bathochromic
shifts of the UV spectra of 4 formulas of ACs were observed at peak
wavelengths of about 510-620 nm by 10 nm suggesting complex
formation. FTIR spectra of the ACs indicate shifts of peaks from
1,733 cm-1 to 1,696 cm-1 indicating interactions and a decrease in the
peak areas within the wavenumber of 3,400-3,500 cm-1 indicating
changes in hydrogen bonding. Thermal analysis of all of the ACs
suggests increases in melting temperature after complexation. AC
with the highest melting temperature was morphologically observed
by SEM and TEM to be crystal-like particles within a range of 50 to
200 nm. Particle size analysis of the AC by laser diffraction gave a
range of 50-600 nm, indicating aggregation. This AC was shown to
have no cytotoxic effect on cultured HGEPp0.5 and HGF (all p>
0.05) by MTT. Therefore, complexation of anthocyanins was simple
and self-assembly process, potentially resulting in nanosized particles
of anthocyanin complex.
Abstract: Anthocyanins are natural pigments with effective UV
protection but their topical use could be limited due to their
physicochemical characteristics. An attempt to overcome such
limitations by complexation of 2 major anthocyanin-rich sources, C.
ternatea and Z. mays, has potentiated its use as topical antiinflammatory.
Cell studies indicate no cytotoxicity of the
anthocyanin complex (AC) up to 1 mg/ml tested in HaCaT and
human fore head fibroblasts by MTT. Croton oil-induced ear edema
in Wistar rats suggests an effective dose of 5 mg/cm2 of AC as a
topical anti-inflammatory in comparison to 0.5 mg/cm2 of
fluocinolone acetonide. Niosomal encapsulation of the AC
significantly prolonged the anti-inflammatory activity particularly at
8 h after topical application (p = 0.0001). The AC was not cytotoxic
and its anti-inflammatory and activity was dose-dependent and
prolonged by niosomal encapsulation. It has also shown to promote
collagen type 1 production in cell culture. Thus, AC could be a
potential candidate for topical anti-inflammatory agent from natural
resources.
Abstract: Food is widely packaged with plastic materials to
prevent microbial contamination and spoilage. Ionizing radiation is
widely used to sterilize the food-packaging materials. Sterilization by
γ-radiation causes degradation such as embrittlement, stiffening,
softening, discoloration, odour generation, and decrease in molecular
weight. Many antioxidants can prevent γ-degradation but most of
them are toxic. The migration of antioxidants to its environment
gives rise to major concerns in case of food packaging plastics. In
this attempt, we have aimed to utilize synergistic mixtures of
stabilizers which are approved for food-contact applications.
Ethylene-propylene-diene terpolymer has been melt-mixed with
hindered amine stabilizers (HAS), phenolic antioxidants and organophosphites
(hydroperoxide decomposer). Results were discussed by
comparing the stabilizing efficiency of mixtures with and without
phenol system. Among phenol containing systems where we mostly
observed discoloration due to the oxidation of hindered phenol, the
combination of secondary HAS, tertiary HAS, organo-phosphite and
hindered phenol exhibited improved stabilization efficiency than
single or binary additive systems. The mixture of secondary HAS and
tertiary HAS, has shown antagonistic effect of stabilization.
However, the combination of organo-phosphite with secondary HAS,
tertiary HAS and phenol antioxidants have been found to give
synergistic even at higher doses of Gamma-irradiation. The effects
have been explained through the interaction between the stabilizers.
After γ-irradiation, the consumption of oligomeric stabilizer
significantly depends on the components of stabilization mixture. The
effect of the organo-phosphite antioxidant on the overall stability has
been discussed.
Abstract: Adsorption of a boron nitride nanotube (BNNT) was
examined toward ethylacetylene (C4H6) molecule by using density
functional theory (DFT) calculations at the B3LYP/6-31G (d) level,
and it was found that the adsorption energy (Ead) of ethylacetylene
the pristine nanotubes is about -1.60kcal/mol. But when nanotube has
been doped with Si and Al atoms, the adsorption energy of
ethylacetylene molecule was increased. Calculation showed that
when the nanotube is doping by Al, the adsorption energy is about -
24.19kcal/mol and also the amount of HOMO/LUMO energy gap
(Eg) will reduce significantly. Boron nitride nanotube is a suitable
adsorbent for ethylacetylene and can be used in separation processes
ethylacetylene. It is seem that nanotube (BNNT) is a suitable
semiconductor after doping, and the doped BNNT in the presence of
ethylacetylene an electrical signal is generating directly and therefore
can potentially be used for ethylacetylene sensors.
Abstract: Rotary draw bending is a method which is being used
in tube forming. In the tube bending process, the neutral axis moves
towards the inner arc and the wall thickness distribution changes for
tube’s cross section. Thinning takes place in the outer arc of the tube
(extrados) due to the stretching of the material, whereas thickening
occurs in the inner arc of the tube (intrados) due to the comparison of
the material. The calculations of the wall thickness distribution,
neutral axis shifting, and strain distribution have not been accurate
enough, so far. The previous model (the geometrical model)
describes the neutral axis shifting and wall thickness distribution. The
geometrical of the tube, bending radius and bending angle are
considered in the geometrical model, while the influence of the
material properties of the tube forming are ignored. The advanced
model is a modification of the previous model using material
properties that depends on the correction factor. The correction factor
is a purely empirically determined factor. The advanced model was
compared with the Finite element simulation (FE simulation) using a
different bending factor (Bf =bending radius/ diameter of the tube),
wall thickness (Wf = diameter of the tube/ wall thickness), and
material properties (strain hardening exponent). Finite element model
of rotary draw bending has been performed in PAM-TUBE program
(version: 2012). Results from the advanced model resemble the FE
simulation and the experimental test.
Abstract: Content-based image retrieval (CBIR) uses the
contents of images to characterize and contact the images. This paper
focus on retrieving the image by separating images into its three color
mechanism R, G and B and for that Discrete Wavelet Transformation
is applied. Then Wavelet based Generalized Gaussian Density (GGD)
is practical which is used for modeling the coefficients from the
wavelet transforms. After that it is agreed to Histogram of Oriented
Gradient (HOG) for extracting its characteristic vectors with Relevant
Feedback technique is used. The performance of this approach is
calculated by exactness and it confirms that this method is wellorganized
for image retrieval.
Abstract: Composite materials, due to their unique properties
such as high strength to weight ratio, corrosion resistance, and impact
resistance have huge potential as structural materials in automotive,
construction and transportation applications. However, these
properties often come at higher cost owing to complex design
methods, difficult manufacturing processes and raw material cost.
Traditionally, tapered laminated composite structures are
manufactured using autoclave manufacturing process by ply drop off
technique. Autoclave manufacturing though very powerful suffers
from high capital investment and higher energy consumption. As per
the current trends in composite manufacturing, Out of Autoclave
(OoA) processes are looked as emerging technologies for
manufacturing the structural composite components for aerospace
and defense applications. However, there is a need for improvement
among these processes to make them reliable and consistent. In this
paper, feasibility of using out of autoclave process to manufacture the
variable thickness cantilever beam is discussed. The minimum weight
design for the composite beam is obtained using constant stress beam
concept by tailoring the thickness of the beam. Ply drop off
techniques was used to fabricate the variable thickness beam from
glass/epoxy prepregs. Experiments were conducted to measure
bending stresses along the span of the cantilever beam at different
intervals by applying the concentrated load at the free end.
Experimental results showed that the stresses in the bean at different
intervals were constant. This proves the ability of OoA process to
manufacture the constant stress beam. Finite element model for the
constant stress beam was developed using commercial finite element
simulation software. It was observed that the simulation results
agreed very well with the experimental results and thus validated
design and manufacturing approach used.
Abstract: For cycling, the analysis of the pedal force is one of the
important factors in the study of exercise ability assessment and
overuse injuries. In past studies, a two-axis measurement sensor was
used at the sagittal plane to measure the force only in the anterior,
posterior, and vertical directions and to analyze the loss of force and
the injury on the frontal plane due to the forces in the right and left
directions. In this study, which is a basic study on diverse analyses of
the pedal force that consider the forces on the sagittal plane and the
frontal plane, a three-axis pedal force measurement sensor was
developed to measure the anterior-posterior (Fx), medio-lateral (Fz),
and vertical (Fy) forces. The sensor was fabricated with a size and
shape similar to those of the general flat pedal, and had a 550g weight
that allowed smooth pedaling. Its measurement range was ±1000 N for
Fx and Fz and ±2000 N for Fy, and its non-linearity, hysteresis, and
repeatability were approximately 0.5%. The data were sampled at
1000 Hz using a signal collector. To use the developed sensor, the
pedaling efficiency (index of efficiency, IE) and the range of left and
right (medio-lateral, ML) forces were measured with two seat heights
(low and high). The results of the measurement showed that the IE was
higher and the force range in the ML direction was lower with the high
position than with the low position. The developed measurement
sensor and its application results will be useful in understanding and
explaining the complicated pedaling technique, and will enable
diverse kinematic analyses of the pedal force on the sagittal plane and
the frontal plane.
Abstract: The effect of the inclusion of thyme and rosemary
essential oils into chitosan films, as well as the microbiological and
physical properties when storing chitosan film with and without the
mentioned inclusion was studied. The film forming solution was
prepared by dissolving chitosan (2%, w/v), polysorbate 80 (4% w/w
CH) and glycerol (16% w/w CH) in aqueous lactic acid solutions
(control). The thyme (TEO) and rosemary (REO) essential oils (EOs)
were included 1:1 w/w (EOs:CH) on their combination 50/50
(TEO:REO). The films were stored at temperatures of 5, 20, 33°C
and a relative humidity of 75% during four weeks. The films with
essential oil inclusion did not show an antimicrobial activity against
strains. This behavior could be explained because the chitosan only
inhibits the growth of microorganisms in direct contact with the
active sites. However, the inhibition capacity of TEO was higher than
the REO and a synergic effect between TEO:REO was found for S.
enteritidis strains in the chitosan solution.
Some physical properties were modified by the inclusion of
essential oils. The addition of essential oils does not affect the
mechanical properties (tensile strength, elongation at break, puncture
deformation), the water solubility, the swelling index nor the DSC
behavior. However, the essential oil inclusion can significantly
decrease the thickness, the moisture content, and the L* value of
films whereas the b* value increased due to molecular interactions
between the polymeric matrix, the loosing of the structure, and the
chemical modifications. On the other hand, the temperature and time
of storage changed some physical properties on the chitosan films.
This could have occurred because of chemical changes, such as
swelling in the presence of high humidity air and the reacetylation of
amino groups. In the majority of cases, properties such as moisture
content, tensile strength, elongation at break, puncture deformation,
a*, b*, chrome, 7E increased whereas water resistance, swelling
index, L*, and hue angle decreased.
Abstract: The design, manufacture, and operation of thin-walled
pressure vessels must be based on maximum safe operating pressure
and an adequate factor of safety (FoS). This research paper first
reports experimental evaluation of longitudinal and hoops stresses
based on working pressure as well as maximum pressure; and then
includes a critical study of factor of safety (FoS) in the design of a
glass fiber pressure vessel. Experimental work involved the use of
measuring instruments and the readings from pressure gauges.
Design calculations involved the computations of design stress and
FoS; the latter was based on breaking strength of 55 MPa for the
glass fiber (pressure-vessel material). The experimentally determined
FoS value has been critically compared with the general FoS allowed
in the design of glass fiber pressure vessels.
Abstract: The present study was carried out to evaluate the
effect of different levels of dietary seed and extract of Harmal
(Peganum harmala L.) on immunity of broiler chicks. A total of 350
one-day old broiler chicks (Ross 308) were randomly allocated to
five dietary treatments with four replicates pen of 14 birds each.
Dietary treatments consisted of control, 1 and 2 g/kg Harmal seed in
diet, 100 and 200 mg/L Harmal seed extract in water. Broilers
received dietary treatments from 1 to 42 d. Two birds from each pen
were randomly weighed and sacrificed at 42 d of age, the relative
weight of lymphoid organs (bursa of Fabercius and spleen) to live
weight were calculated. Antibody titers against Newcastle and
influenza viruses and sheep red blood cell were measured at 30 d of
age. Results showed that the relative weights of lymphoid organs
were not affected by dietary treatments. Furthermore, antibody titer
against Newcastle and influenza viruses as well as sheep red blood
cell antigen were significantly (P
Abstract: To date, one of the few comprehensive indicators for
the measurement of food security is the Global Food Security Index
(GFSI). This index is a dynamic quantitative and qualitative
benchmarking model, constructed from 28 unique indicators, that
measures drivers of food security across both developing and
developed countries. Whereas the GFSI has been calculated across a
set of 109 countries, in this paper we aim to present and compare, for
the Middle East and North Africa (MENA), 1) the Food Security
Index scores achieved and 2) the data available on affordability,
availability, and quality of food. The data for this work was taken
from the latest available report published by the creators of the GFSI,
which in turn used information from national and international
statistical sources. MENA countries rank from place 17/109 (Israel,
although with resent political turmoil this is likely to have changed)
to place 91/109 (Yemen) with household expenditure spent in food
ranging from 15.5% (Israel) to 60% (Egypt). Lower spending on food
as a share of household consumption in most countries and better
food safety net programs in the MENA have contributed to a notable
increase in food affordability. The region has also, however,
experienced a decline in food availability, owing to more limited
food supplies and higher volatility of agricultural production. In
terms of food quality and safety the MENA has the top ranking
country (Israel). The most frequent challenges faced by the countries
of the MENA include public expenditure on agricultural research and
development as well as volatility of agricultural production. Food
security is a complex phenomenon that interacts with many other
indicators of a country’s wellbeing; in the MENA it is slowly but
markedly improving.
Abstract: Lightweight design represents an important key to
successful implementation of energy-saving, fuel-efficient and
environmentally friendly means of transport in the aerospace and
automotive industry. In this context the use of carbon fibre reinforced
plastics (CFRP) which are distinguished by their outstanding
mechanical properties at relatively low weight, promise significant
improvements. Due to the reduction of the total mass, with the
resulting lowered fuel or energy consumption and CO2 emissions
during the operational phase, commercial aircraft will increasingly be
made of CFRP. An auspicious technology for the efficient and
economic production of high performance thermoset composites and
hybrid structures for future lightweight applications is the
combination of carbon fibre sheet moulding compound, tailored
continuous carbon fibre reinforcements and metallic components in a
one-shot pressing and curing process. This paper deals with a hybrid
composite technology for aerospace industries, which was developed
with the help of a special innovation and development system.
Abstract: This paper investigates the activity of the rectus
femoris (RF) and biceps femoris (BF) in healthy subjects during salat
(prostration) and specific exercise (squat exercise) using
electromyography (EMG). A group of undergraduates aged between
19 to 25 years voluntarily participated in this study. The myoelectric
activity of the muscles were recorded and analyzed. The finding
indicated that there were contractions of the muscles during the salat
and exercise with almost same EMG’s level. From the result,
Wilcoxon’s Rank Sum test showed significant difference between
prostration and squat exercise (p
Abstract: This paper presents the development of a single-ended 38.5 kS/s 10-bit programmable reference SAR ADC which is realized in MIMOS’s 0.35 µm CMOS process. The design uses a resistive DAC, a dynamic comparator with pre-amplifier and a SAR digital logic to create 10 effective bits ADC. A programmable reference circuitry allows the ADC to operate with different input range from 0.6 V to 2.1 V. The ADC consumed less than 7.5 mW power with a 3 V supply.
Abstract: A thermosyphon system is a heat transfer loop which
operates on the basis of gravity and buoyancy forces. It guarantees a
good reliability and low maintenance cost as it does not involve any
mechanical pump. Therefore, it can be used in many industrial
applications such as refrigeration and air conditioning, electronic
cooling, nuclear reactors, geothermal heat extraction, etc. But flow
instabilities and loop configuration are the major problems in this
system. Several previous researchers studied that stabilities can be
suppressed by using nanofluids as loop fluid. In the present study a
rectangular thermosyphon loop with end heat exchangers are
considered for the study. This configuration is more appropriate for
many practical applications such as solar water heater, geothermal
heat extraction, etc. In the present work, steady-state analysis is
carried out on thermosyphon loop with parallel flow coaxial heat
exchangers at heat source and heat sink. In this loop nanofluid is
considered as the loop fluid and water is considered as the external
fluid in both hot and cold heat exchangers. For this analysis onedimensional
homogeneous model is developed. In this model,
conservation equations like conservation of mass, momentum, energy
are discretized using finite difference method. A computer code is
written in MATLAB to simulate the flow in thermosyphon loop. A
comparison in terms of heat transfer is made between water and
nanofluid as working fluids in the loop.
Abstract: A Distributed Denial of Service (DDoS) attack is a
major threat to cyber security. It originates from the network layer or
the application layer of compromised/attacker systems which are
connected to the network. The impact of this attack ranges from the
simple inconvenience to use a particular service to causing major
failures at the targeted server. When there is heavy traffic flow to a
target server, it is necessary to classify the legitimate access and
attacks. In this paper, a novel method is proposed to detect DDoS
attacks from the traces of traffic flow. An access matrix is created
from the traces. As the access matrix is multi dimensional, Principle
Component Analysis (PCA) is used to reduce the attributes used for
detection. Two classifiers Naive Bayes and K-Nearest neighborhood
are used to classify the traffic as normal or abnormal. The
performance of the classifier with PCA selected attributes and actual
attributes of access matrix is compared by the detection rate and
False Positive Rate (FPR).
Abstract: Vertical Handover(VHO) among different
communication technologies ensuring uninterruption and service
continuity is one of the most important performance parameter in
Heterogenous networks environment. In an integrated Universal
Mobile Telecommunicatin System(UMTS) and Wireless Local
Area Network(WLAN), WLAN is given an inherent priority over
UMTS because of its high data rates with low cost. Therefore
mobile users want to be associated with WLAN maximum of the
time while roaming, to enjoy best possible services with low cost.
That encourages reduction of number of VHO. In this work the
reduction of number of VHO with respect to varying number of
WLAN Access Points(APs) in an integrated UMTS and WLAN
network is investigated through simulation to provide best possible
cost effective service to the users. The simulation has been carried
out for an area (7800 × 9006)m2 where COST-231 Hata model
and 3GPP (TR 101 112 V 3.1.0) specified models are used for
WLAN and UMTS path loss models respectively. The handover
decision is triggered based on the received signal level as compared
to the fade margin. Fade margin gives a probabilistic measure of
the reliability of the communication link. A relationship between
number of WLAN APs and the number of VHO is also established
in this work.
Abstract: In this paper, the transient device performance analysis
of n-type Gate Inside JunctionLess Transistor (GI-JLT) has been
evaluated. 3-D Bohm Quantum Potential (BQP) transport device
simulation has been used to evaluate the delay and power dissipation
performance. GI-JLT has a number of desirable device parameters
such as reduced propagation delay, dynamic power dissipation,
power and delay product, intrinsic gate delay and energy delay
product as compared to Gate-all-around transistors GAA-JLT. In
addition to this, various other device performance parameters namely,
on/off current ratio, short channel effects (SCE), transconductance
Generation Factor (TGF) and unity gain cut-off frequency (fT ) and
subthreshold slope (SS) of the GI-JLT and GAA-JLT have been
analyzed and compared. GI-JLT shows better device performance
characteristics than GAA-JLT for low power and high frequency
applications, because of its larger gate electrostatic control on the
device operation.