Abstract: The effect of autofrettage process in strain hardened
thick-walled pressure vessels has been investigated theoretically by
finite element modeling. Equivalent von Mises stress is used as yield
criterion to evaluate the optimum autofrettage pressure and the
optimum radius of elastic-plastic junction. It has been observed that
the optimum autofrettage pressure increases along with the working
pressure. For two different working pressures, the effect of the ratio
of outer to inner radius (b/a=k) value on the optimum autofrettage
pressure is also noticed. The Optimum autofrettage pressure solely
depends on K value rather than on the inner or outer radius.
Furthermore, percentage reduction of von Mises stresses is compared
for different working pressures and different k values. Maximum von
Mises stress developed at different autofrettage pressure is equated
for elastic perfectly plastic and elastic-plastic material with different
slope of strain hardening segment. Cylinder material having higher
slope of strain hardening segment provides better benedictions in the
autofrettage process.
Abstract: A plausible architecture of an ancient genetic code is derived from an extended base triplet vector space over the Galois field of the extended base alphabet {D, G, A, U, C}, where the letter D represent one or more hypothetical bases with unspecific pairing. We hypothesized that the high degeneration of a primeval genetic code with five bases and the gradual origin and improvements of a primitive DNA repair system could make possible the transition from the ancient to the modern genetic code. Our results suggest that the Watson-Crick base pairing and the non-specific base pairing of the hypothetical ancestral base D used to define the sum and product operations are enough features to determine the coding constraints of the primeval and the modern genetic code, as well as the transition from the former to the later. Geometrical and algebraic properties of this vector space reveal that the present codon assignment of the standard genetic code could be induced from a primeval codon assignment. Besides, the Fourier spectrum of the extended DNA genome sequences derived from the multiple sequence alignment suggests that the called period-3 property of the present coding DNA sequences could also exist in the ancient coding DNA sequences.
Abstract: Clustering categorical data is more complicated than
the numerical clustering because of its special properties. Scalability
and memory constraint is the challenging problem in clustering large
data set. This paper presents an incremental algorithm to cluster the
categorical data. Frequencies of attribute values contribute much in
clustering similar categorical objects. In this paper we propose new
similarity measures based on the frequencies of attribute values and
its cardinalities. The proposed measures and the algorithm are
experimented with the data sets from UCI data repository. Results
prove that the proposed method generates better clusters than the
existing one.
Abstract: Antifungal activities of ether and methanolic extracts of volatiles oils of Nigella Sativa seeds were tested against pathogenic bacterias and fungies strains.The volatile oil were found to have significant antifungal and antibacterial activities compare to tetracycline, cefuroxime and ciprofloxacin positive controls.The ether and methanolic esxtracts were compared to each other for antifungal and antibacterial activities and ether extracts showed stonger activity than methanolic one.
Abstract: The effect of plant growth-promoting rhizobacteria
(PGPR) on seed germination, seedling growth and yield of field
grown maize were evaluated in three experiments. In these
experiments six bacterial strains include P.putida strain R-168,
P.fluorescens strain R-93, P.fluorescens DSM 50090, P.putida
DSM291, A.lipoferum DSM 1691, A.brasilense DSM 1690 were
used. Results of first study showed seed Inoculation significantly
enhanced seed germination and seedling vigour of maize. In second
experiment, leaf and shoot dry weight and also leaf surface area
significantly were increased by bacterial inoculation in both sterile
and non-sterile soil. The results showed that inoculation with
bacterial treatments had a more stimulating effect on growth and
development of plants in nonsterile than sterile soil. In the third
experiment, Inoculation of maize seeds with all bacterial strains
significantly increased plant height, 100 seed weight, number of seed
per ear and leaf area .The results also showed significant increase in
ear and shoot dry weight of maize.
Abstract: In this paper, a novel multipurpose audio watermarking
algorithm is proposed based on Vector Quantization (VQ) in Discrete
Cosine Transform (DCT) domain using the codeword labeling and
index-bit constrained method. By using this algorithm, it can fulfill the
requirements of both the copyright protection and content integrity
authentication at the same time for the multimedia artworks. The
robust watermark is embedded in the middle frequency coefficients of
the DCT transform during the labeled codeword vector quantization
procedure. The fragile watermark is embedded into the indices of the
high frequency coefficients of the DCT transform by using the
constrained index vector quantization method for the purpose of
integrity authentication of the original audio signals. Both the robust
and the fragile watermarks can be extracted without the original audio
signals, and the simulation results show that our algorithm is effective
with regard to the transparency, robustness and the authentication
requirements
Abstract: The tensile properties of Mg-3%Al nanocrystalline
alloys were investigated at different test environment. Bulk
nanocrystalline samples of these alloy was successfully prepared by
mechanical alloying (MA) followed by cold compaction, sintering,
and hot extrusion process. The crystal size of the consolidated milled
sample was calculated by X-Ray line profile analysis. The
deformation mechanism and microstructural characteristic at
different test condition was discussed extensively. At room
temperature, relatively lower value of activation volume (AV) and
higher value of strain rate sensitivity (SRS) suggests that new rate
controlling mechanism accommodating plastic flow in the present
nanocrystalline sample. The deformation behavior and the
microstructural character of the present samples were discussed in
details.
Abstract: The Constraints imposed by non-thermal
leptogenesis on the survival of the neutrino mass models describing
the presently available neutrino mass patterns, are studied
numerically. We consider the Majorana CP violating phases coming
from right-handed Majorana mass matrices to estimate the baryon
asymmetry of the universe, for different neutrino mass models
namely quasi-degenerate, inverted hierarchical and normal
hierarchical models, with tribimaximal mixings. Considering two
possible diagonal forms of Dirac neutrino mass matrix as either
charged lepton or up-quark mass matrix, the heavy right-handed
mass matrices are constructed from the light neutrino mass matrix.
Only the normal hierarchical model leads to the best predictions of
baryon asymmetry of the universe, consistent with observations in
non-thermal leptogenesis scenario.
Abstract: Viral influenza A subtypes H5N1 and pandemic
H1N1 (pH1N1) have worldwide emerged and transmitted. The most
common anti-influenza drug for treatment of both seasonal and
pandemic influenza viruses is oseltamivir that nowadays becomes
resistance to influenza neuraminidase. The novel long-acting drug,
laninamivir, was discovered for treatment of the patients infected
with influenza B and influenza A viruses. In the present study,
laninamivir complexed with wild-type strain of both H5N1 and
pH1N1 viruses were comparatively determined the structures and
drug-target interactions by means of molecular dynamics (MD)
simulations. The results show that the hydrogen bonding interactions
formed between laninamivir and its binding residues are likely
similar for the two systems. Additionally, the presence of
intermolecular interactions from laninamivir to the residues in the
binding pocket is established through their side chains in accordance
with hydrogen bond interactions.
Abstract: Grid environments consist of the volatile integration
of discrete heterogeneous resources. The notion of the Grid is to
unite different users and organisations and pool their resources into
one large computing platform where they can harness, inter-operate,
collaborate and interact. If the Grid Community is to achieve this
objective, then participants (Users and Organisations) need to be
willing to donate or share their resources and permit other
participants to use their resources. Resources do not have to be
shared at all times, since it may result in users not having access to
their own resource. The idea of reward-based computing was
developed to address the sharing problem in a pragmatic manner.
Participants are offered a reward to donate their resources to the
Grid. A reward may include monetary recompense or a pro rata share
of available resources when constrained. This latter point may imply
a quality of service, which in turn may require some globally agreed
reservation mechanism. This paper presents a platform for economybased
computing using the WebCom Grid middleware. Using this
middleware, participants can configure their resources at times and
priority levels to suit their local usage policy. The WebCom system
accounts for processing done on individual participants- resources
and rewards them accordingly.
Abstract: When considering the development of constitutive
equations describing the behavior of materials under cyclic plastic
strains, different kinds of formulations can be adopted. The primary
intention of this study is to develop computer programming of
plasticity models to accurately predict the life of engineering
components. For this purpose, the energy or cyclic strain is computed
in multi-surface plasticity models in non-proportional loading and to
present their procedures and codes results.
Abstract: In this paper we are interested in classification problems
with a performance constraint on error probability. In such
problems if the constraint cannot be satisfied, then a rejection option
is introduced. For binary labelled classification, a number of SVM
based methods with rejection option have been proposed over the
past few years. All of these methods use two thresholds on the SVM
output. However, in previous works, we have shown on synthetic data
that using thresholds on the output of the optimal SVM may lead to
poor results for classification tasks with performance constraint. In
this paper a new method for supervised classification with rejection
option is proposed. It consists in two different classifiers jointly
optimized to minimize the rejection probability subject to a given
constraint on error rate. This method uses a new kernel based linear
learning machine that we have recently presented. This learning
machine is characterized by its simplicity and high training speed
which makes the simultaneous optimization of the two classifiers
computationally reasonable. The proposed classification method with
rejection option is compared to a SVM based rejection method
proposed in recent literature. Experiments show the superiority of
the proposed method.
Abstract: The growing health hazardous impact of arsenic (As)
contamination in environment is the impetus of the present
investigation. Application of lactic acid bacteria (LAB) for the
removal of toxic and heavy metals from water has been reported.
This study was performed in order to isolate and characterize the Asresistant
LAB from mud and sludge samples for using as efficient As
uptaking probiotic. Isolation of As-resistant LAB colonies was
performed by spread plate technique using bromocresol purple
impregnated-MRS (BP-MRS) agar media provided with As @ 50
μg/ml. Isolated LAB were employed for probiotic characterization
process, acid and bile tolerance, lactic acid production, antibacterial
activity and antibiotic tolerance assays. After As-resistant and
removal characterizations, the LAB were identified using 16S rDNA
sequencing. A total of 103 isolates were identified as As-resistant
strains of LAB. The survival of 6 strains (As99-1, As100-2, As101-3,
As102-4, As105-7, and As112-9) was found after passing through the
sequential probiotic characterizations. Resistant pattern pronounced
hollow zones at As concentration >2000 μg/ml in As99-1, As100-2,
and As101-3 LAB strains, whereas it was found at ~1000 μg/ml in
rest 3 strains. Among 6 strains, the As uptake efficiency of As102-4
(0.006 μg/h/mg wet weight of cell) was higher (17 – 209%)
compared to remaining LAB. 16S rDNA sequencing data of 3 (As99-
1, As100-2, and As101-3) and 3 (As102-4, As105-7, and As112-9)
LAB strains clearly showed 97 to 99% (340 bp) homology to
Pediococcus dextrinicus and Pediococcus acidilactici, respectively.
Though, there was no correlation between the metal resistant and
removal efficiency of LAB examined but identified elevated As
removing LAB would probably be a potential As uptaking probiotic
agent. Since present experiment concerned with only As removal
from pure water, As removal and removal mechanism in natural
condition of intestinal milieu should be assessed in future studies.
Abstract: In the context of large volume Big Divisor (nearly)
SLagy D3/D7 μ-Split SUSY [1], after an explicit identification
of first generation of SM leptons and quarks with fermionic superpartners
of four Wilson line moduli, we discuss the identification of
gravitino as a potential dark matter candidate by explicitly calculating
the decay life times of gravitino (LSP) to be greater than age of
universe and lifetimes of decays of the co-NLSPs (the first generation
squark/slepton and a neutralino) to the LSP (the gravitino) to be
very small to respect BBN constraints. Interested in non-thermal
production mechanism of gravitino, we evaluate the relic abundance
of gravitino LSP in terms of that of the co-NLSP-s by evaluating
their (co-)annihilation cross sections and hence show that the former
satisfies the requirement for a potential Dark Matter candidate. We
also show that it is possible to obtain a 125 GeV light Higgs in our
setup.
Abstract: This paper presents an adaptive nonlinear position
controller with velocity constraint, capable of combining the
input-output linearization technique and Lyapunov stability theory.
Based on the Lyapunov stability theory, the adaptation law of the
proposed controller is derived along with the verification of the overall
system-s stability. Computer simulation results demonstrate that the
proposed controller is robust and it can ensure transient stability of
BLDCM, under the occurrence of a large sudden fault.
Abstract: An experimental study of Reinforced Concrete, RC, columns strengthened using a steel jacketing technique was conducted. The jacketing technique consisted of four steel vertical angles installed at the corners of the column joined by horizontal steel straps confining the column externally. The effectiveness of the technique was evaluated by testing the RC column specimens under eccentric monotonic loading until failure occurred. Strain gauges were installed to monitor the strains in the internal reinforcement as well as the external jacketing system. The effectiveness of the jacketing technique was demonstrated, and the parameters affecting the technique were studied.
Abstract: In this research, Forming Limit Diagrams for supertension
sheet metals which are using in automobile industry have
been obtained. The exerted strains to sheet metals have been
measured with four different methods and the errors of each method
have also been represented. These methods have been compared with
together and the most efficient and economic way of extracting of the
exerted strains to sheet metals has been introduced. In this paper total
error and uncertainty of FLD extraction procedures have been
derived. Determination of the measurement uncertainty in extracting
of FLD has a great importance in design and analysis of the sheet
metal forming process.
Abstract: In this study, a mathematical model was proposed and
the accuracy of this model was assessed to predict the growth of
Pseudomonas aeruginosa and rhamnolipid production under nitrogen
limiting (sodium nitrate) fed-batch fermentation. All of the
parameters used in this model were achieved individually without
using any data from the literature.
The overall growth kinetic of the strain was evaluated using a
dual-parallel substrate Monod equation which was described by
several batch experimental data. Fed-batch data under different
glycerol (as the sole carbon source, C/N=10) concentrations and feed
flow rates were used to describe the proposed fed-batch model and
other parameters. In order to verify the accuracy of the proposed
model several verification experiments were performed in a vast
range of initial glycerol concentrations. While the results showed an
acceptable prediction for rhamnolipid production (less than 10%
error), in case of biomass prediction the errors were less than 23%. It
was also found that the rhamnolipid production by P. aeruginosa was
more sensitive at low glycerol concentrations.
Based on the findings of this work, it was concluded that the
proposed model could effectively be employed for rhamnolipid
production by this strain under fed-batch fermentation on up to 80 g l-
1 glycerol.
Abstract: This work addresses the problem of optimizing
completely batch water-using network with multiple contaminants
where the flow change caused by mass transfer is taken into
consideration for the first time. A mathematical technique for
optimizing water-using network is proposed based on
source-tank-sink superstructure. The task is to obtain the freshwater
usage, recycle assignments among water-using units, wastewater
discharge and a steady water-using network configuration by
following steps. Firstly, operating sequences of water-using units are
determined by time constraints. Next, superstructure is simplified by
eliminating the reuse and recycle from water-using units with
maximum concentration of key contaminants. Then, the non-linear
programming model is solved by GAMS (General Algebra Model
System) for minimum freshwater usage, maximum water recycle and
minimum wastewater discharge. Finally, numbers of operating periods
are calculated to acquire the steady network configuration. A case
study is solved to illustrate the applicability of the proposed approach.
Abstract: Dynamic bandwidth allocation in EPONs can be
generally separated into inter-ONU scheduling and intra-ONU scheduling. In our previous work, the active intra-ONU scheduling
(AS) utilizes multiple queue reports (QRs) in each report message to cooperate with the inter-ONU scheduling and makes the granted
bandwidth fully utilized without leaving unused slot remainder (USR).
This scheme successfully solves the USR problem originating from the
inseparability of Ethernet frame. However, without proper setting of
threshold value in AS, the number of QRs constrained by the IEEE
802.3ah standard is not enough, especially in the unbalanced traffic
environment. This limitation may be solved by enlarging the threshold
value. The large threshold implies the large gap between the adjacent QRs, thus resulting in the large difference between the best granted bandwidth and the real granted bandwidth. In this paper, we integrate
AS with a cooperative prediction mechanism and distribute multiple
QRs to reduce the penalty brought by the prediction error.
Furthermore, to improve the QoS and save the usage of queue reports,
the highest priority (EF) traffic which comes during the waiting time is
granted automatically by OLT and is not considered in the requested
bandwidth of ONU. The simulation results show that the proposed
scheme has better performance metrics in terms of bandwidth
utilization and average delay for different classes of packets.