Abstract: In this study, a 3D combustion chamber was simulated
using FLUENT 6.32. Aim to obtain detailed information on
combustion characteristics and _ nitrogen oxides in the furnace and
the effect of oxygen enrichment in a combustion process. Oxygenenriched
combustion is an effective way to reduce emissions. This
paper analyzes NO emission, including thermal NO and prompt NO.
Flow rate ratio of air to fuel is varied as 1.3, 3.2 and 5.1 and the
oxygen enriched flow rates are 28, 54 and 68 lit/min. The 3D
Reynolds Averaged Navier Stokes (RANS) equations with standard
k-ε turbulence model are solved together by Fluent 6.32 software.
First order upwind scheme is used to model governing equations and
the SIMPLE algorithm is used as pressure velocity coupling. Results
show that for AF=1.3, increase the oxygen flow rate of oxygen
reduction in NO emissions is Lance. Moreover, in a fixed oxygen
enrichment condition, increasing the air to fuel ratio will increase the
temperature peak, but not the NO emission rate. As a result, oxygen
enrichment can reduce the NO emission at this kind of furnace in low
air to fuel rates.
Abstract: This study investigated the ecological effects of
particulate pollution from a cement factory on the vegetation in the
western Mediterranean coastal desert of Egypt. Variations in
vegetation, soil chemical characters, and some responses of Atriplex
halimus, as a dominant species in the study area, were investigated in
some sites located in different directions from the cement factory
between Burg El-Arab in the east and El-Hammam in the west. The
results showed an obvious decrease in vegetation diversity, in
response to cement-kiln dust pollution, that accompanied by a high
dominance attributed to the high contribution of Atriplex halimus.
Annual species were found to be more sensitive to cement dust
pollution as they all failed to persist in highly disturbed sites. It is
remarkable that cover and phytomass of Atriplex halimus were
increased greatly in response to cement dust pollution, and this was
accompanied by a reduction in the mature seeds and leaf-area of the
plant. The few seeds of the affected individuals seemed to be more
fertile and attained higher germination percentages and exhibited
hardening against drought stress.
Abstract: The risk of water erosion is one of the main
environmental concerns in the southern Mediterranean regions. Thus,
quantification of soil loss is an important issue for soil and water
conservation managers. The objective of this paper is to examine the
applicability of the Soil and Water Assessment Tool (SWAT) model
in The Sarrath river catchment, North of Tunisia, and to identify the
most vulnerable areas in order to help manager implement an
effective management program. The spatial analysis of the results
shows that 7 % of the catchment experiences very high erosion risk,
in need for suitable conservation measures to be adopted on a priority
basis. The spatial distribution of erosion risk classes estimated 3%
high, 5,4% tolerable, and 84,6% low. Among the 27 delineated subcatchments
only 4 sub-catchments are found to be under high and
very high soil loss group, two sub-catchments fell under moderate
soil loss group, whereas other sub-catchments are under low soil loss
group.
Abstract: We propose an all optical flip-flop circuit composedof two Silicon-on-insulator microring resonators coupled to straightwaveguides by exploiting the optical bistability behavior due to thenonlinear Kerr effect. We used the transfer matrix analysis toinvestigate continuous wave propagation through microrings, as wellwe considered the nonlinear switching characteristics of an opticaldevice using a double-coupler silicon ring resonator in presence ofthe Kerr nonlinearity, thus obtaining the bistability behavior of theoutput port, the drop port and also inside the silicon microringresonator. It is shown that the bistability behavior depends on thecontrol of the input wavelength.KeywordsAll optical flip-flops, Kerr effect, microringresonator, optical bistability.
Abstract: Bacillus subtilis strain LB5 produced lipopeptide
antibiotic iturin A-2 in liquid medium. Crude extract
from cell-free supernatant of B. subtilis cultivated broth extracted
with n-butanol showed antifungal activity to conidial germination of
Colletotrichum gloeosporioides. The germination of conidia was
completely inhibited by crude extract. The ultrastructure of conidia
after treated with crude extract was found an accumulation of vesiclelike
material between cell wall and plasma membrane while this
accumulation was not observed in untreated and germinated conidia.
Besides, the cell wall was not affected by crude extract.
Abstract: This study carried out to determine the effect of plant
densities on some agronomic characteristics of four safflower cultivars in spring planting. The experiment was conducted at Yazd,
Iran- using a factorial in a randomized complete block design with four replications. Cultivars were including Arak, IL, Asteria and Local and plant densities were 10, 13.3, 20 and 40 plant/m2. Number
of seeds/head, number of heads/plant, HI, 1000-seed weight and seed yield significantly decreased as planting density increased. With increasing planting density, LAI, plant height, first branch height and
biological yield increased. The highest seed yield was obtained in 13.3 plant/m2 (2167 kg/ha). There were significant differences
between cultivars. Local cv. had higher seed yield than the other cultivars mainly due to higher heads/plant and seeds/head.
Abstract: This article introduces the actual problem that is а
study of proposed by the authors Hydrocele ointment in amino acids’
metabolism of cows’ blood in inflammation of traumatic origin.
Hydrocele ointment has shown a positive effect on inflammatory
process and amino acids’ metabolism of animals treated with the
drug. Amino acid levels reached physiological parameters on the 10th
day after treatment; in the control group this parameter was higher
than normal.
Abstract: The theoretical investigation is carried out to describe
the effect of increase of pressure waves amplitude in clean and bubbly liquid. The goal of the work is to capture the regime of multiple magnification of acoustic and shock waves in the liquid,
which enables to get appropriate conditions to enlarge collapses of
micro-bubbles. The influence of boundary conditions and frequency
of the governing acoustic field is studied for the case of the
cylindrical acoustic resonator. It has been observed the formation of
standing waves with large amplitude at resonant frequencies. The
interaction of the compression wave with gas and vapor bubbles is
investigated for the convergent channel. It is shown theoretically that
the chemical reactions, which occur inside gas bubbles, provide additional impulse to the wave, that affect strongly on the collapses
of the vapor bubbles
Abstract: As many scientific applications require large data processing, the importance of parallel I/O has been increasingly recognized. Collective I/O is one of the considerable features of parallel I/O and enables application programmers to easily handle their large data volume. In this paper we measured and analyzed the performance of original collective I/O and the subgroup method, the way of using collective I/O of MPI effectively. From the experimental results, we found that the subgroup method showed good performance with small data size.
Abstract: Tolerance is a tool for achieving a social cohesion, particularly, among individuals and groups with different values. The aim is to study the characteristics of the ethnic tolerance, the inhabitants of Latvia. The ethnic tolerance is taught as a set of conscious and unconscious orientations of the individual in social interaction and inter-ethnic communication. It uses the tools of empirical studies of the ethnic tolerance which allows to identify the explicitly and implicitly levels of the emotional component of Latvia's residents. Explicit measurements were made using the techniques of self-report which revealed the index of the ethnic tolerance and the ethnic identity of the participants. The implicit component was studied using methods based on the effect of the emotional priming. During the processing of the results, there were calculated indicators of the positive and negative implicit attitudes towards members of their own and other ethnicity as well as the explicit parameters of the ethnic tolerance and the ethnic identity of Latvia-s residents. The implicit measurements of the ratio of neighboring ethnic groups against each other showed a mutual negative attitude whereas the explicit measurements indicate a neutral attitude. The data obtained contribute to a further study of the ethnic tolerance of Latvia's residents.
Abstract: The functional response of an infective is the relationship
between an infected individual-s infection rate and the abundance
of the number of susceptibles that one can potentially be infected.
In this paper, we consider defensive attitudes for HIV prevention
(primary prevention) while at the same time emphasizing on offensive
attitudes that reduce infection for those infected (secondary prevention).
We look at how defenses can protect an uninfected individual
in the case where high risk groups such as commercial sex workers
and those who deliberately go out to look for partners. We propose
an infection cycle that begins with a search, then an encounter,
a proposal and contact. The infection cycle illustrates the various
steps an infected individual goes through to successfully infect a
susceptible. For heterogeneous transmission of HIV, there will be no
infection unless there is contact. The ability to avoid an encounter,
detection, proposal and contact constitute defense.
Abstract: The recognition of handwritten numeral is an
important area of research for its applications in post office, banks
and other organizations. This paper presents automatic recognition of
handwritten Kannada numerals based on structural features. Five
different types of features, namely, profile based 10-segment string,
water reservoir; vertical and horizontal strokes, end points and
average boundary length from the minimal bounding box are used in
the recognition of numeral. The effect of each feature and their
combination in the numeral classification is analyzed using nearest
neighbor classifiers. It is common to combine multiple categories of
features into a single feature vector for the classification. Instead,
separate classifiers can be used to classify based on each visual
feature individually and the final classification can be obtained based
on the combination of separate base classification results. One
popular approach is to combine the classifier results into a feature
vector and leaving the decision to next level classifier. This method
is extended to extract a better information, possibility distribution,
from the base classifiers in resolving the conflicts among the
classification results. Here, we use fuzzy k Nearest Neighbor (fuzzy
k-NN) as base classifier for individual feature sets, the results of
which together forms the feature vector for the final k Nearest
Neighbor (k-NN) classifier. Testing is done, using different features,
individually and in combination, on a database containing 1600
samples of different numerals and the results are compared with the
results of different existing methods.
Abstract: In this experiment, we investigated the performance of
two types of heat sink, swaged- and extruded-type, used in the inverter
of industrial electricity generator. The swaged-type heat sink has 62
fins, and the extruded-type has 38 fins having the same dimension as
that of the swaged-type. But the extruded-type heat sink maintains the
same heat transfer area by the laterally waved surface which has 1 mm
in radius. As a result, the swaged- and extruded-type heat sinks
released 71% and 64% of the heat incoming to the heat sink,
respectively. The other incoming heat were naturally convected and
radiated to the ambient. In spite of 40% decrease in number of fins, the
heat release performance of the extruded-type heat sink was lowered
only 7% than that of the swaged-type. We believe that, this shows the
increment of effective heat transfer area by the laterally waved surface
of fins and the better heat transfer property of the extruded-type heat
sink.
Abstract: A numerical method for solving the time-independent Schrödinger equation of a particle moving freely in a three-dimensional
axisymmetric region is developed. The boundary of the region
is defined by an arbitrary analytic function. The method uses a
coordinate transformation and an expansion in eigenfunctions. The
effectiveness is checked and confirmed by applying the method to a
particular example, which is a prolate spheroid.
Abstract: VRML( The virtual reality modeling language) is a standard language used to build up 3D virtualized models. The quick development of internet technology and computer manipulation has promoted the commercialization of reality virtualization. VRML, thereof, is expected to be the most effective framework of building up virtual reality. This article has studied plans to build virtualized scenes based on the technology of virtual reality and Java programe, and introduced how to execute real-time data transactions of VRML file and Java programe by applying Script Node, in doing so we have the VRML interactivity being strengthened.
Abstract: High strength concrete (HSC) provides high strength
but lower ductility than normal strength concrete. This low ductility
limits the benefit of using HSC in building safe structures. On the
other hand, when designing reinforced concrete beams, designers
have to limit the amount of tensile reinforcement to prevent the
brittle failure of concrete. Therefore the full potential of the use of
steel reinforcement can not be achieved. This paper presents the idea
of confining concrete in the compression zone so that the HSC will
be in a state of triaxial compression, which leads to improvements in
strength and ductility. Five beams made of HSC were cast and tested.
The cross section of the beams was 200×300 mm, with a length of 4
m and a clear span of 3.6 m subjected to four-point loading, with
emphasis placed on the midspan deflection. The first beam served as
a reference beam. The remaining beams had different tensile
reinforcement and the confinement shapes were changed to gauge
their effectiveness in improving the strength and ductility of the
beams. The compressive strength of the concrete was 85 MPa and the
tensile strength of the steel was 500 MPa and for the stirrups and
helixes was 250 MPa. Results of testing the five beams proved that
placing helixes with different diameters as a variable parameter in the
compression zone of reinforced concrete beams improve their
strength and ductility.
Abstract: Groundwater is one of the most important water
resources in Fars province. Based on this study, 95 percent of the
total annual water consumption in Fars is used for agriculture,
whereas the percentages for domestic and industrial uses are 4 and 1
percent, respectively. Population growth, urban and industrial
growth, and agricultural development in Fars have created a
condition of water stress. In this province, farmers and other users are
pumping groundwater faster than its natural replenishment rate,
causing a continuous drop in groundwater tables and depletion of this
resource. In this research variation of groundwater level, their effects
and ways to help control groundwater levels in aquifer of the Niriz
plains in Fars plain were evaluated .Excessive exploitation of
groundwater in this aquifer caused the groundwater levels fall too
fast or to unacceptable levels. The average drawdown of the
groundwater level in this plain were 9.1 meters during 1997 to
2004. The purpose of this study is to evaluate water level changes in
the Niriz Aquifer in the Fars province in order to determine the areas
of greatest depletion, the cause of depletion, and predict the
remaining life of the aquifer.
Abstract: Climate change is a phenomenon has been based on
the available evidence from a very long time ago and now its
existence is very probable. The speed and nature of climate
parameters changes at the middle of twentieth century has been
different and its quickness more than the before and its trend changed
to some extent comparing to the past. Climate change issue now
regarded as not only one of the most common scientific topic but also
a social political one, is not a new issue. Climate change is a
complicated atmospheric oceanic phenomenon on a global scale and
long-term. Precipitation pattern change, fast decrease of snowcovered
resources and its rapid melting, increased evaporation, the
occurrence of destroying floods, water shortage crisis, severe
reduction at the rate of harvesting agricultural products and, so on are
all the significant of climate change. To cope with this phenomenon,
its consequences and events in which public instruction is the most
important but it may be climate that no significant cant and effective
action has been done so far. The present article is included a part of
one surrey about climate change in Fars. The study area having
annually mean temperature 14 and precipitation 320 mm .23 stations
inside the basin with a common 37 year statistical period have been
applied to the meteorology data (1974-2010). Man-kendal and
change factor methods are two statistical methods, applying them, the
trend of changes and the annual mean average temperature and the
annual minimum mean temperature were studied by using them.
Based on time series for each parameter, the annual mean average
temperature and the mean of annual maximum temperature have a
rising trend so that this trend is clearer to the mean of annual
maximum temperature.
Abstract: Different variants for buoyancy-affected terms in k-ε turbulence model have been utilized to predict the flow parameters more accurately, and investigate applicability of alternative k-ε turbulence buoyant closures in numerical simulation of a horizontal gravity current. The additional non-isotropic turbulent stress due to buoyancy has been considered in production term, based on Algebraic Stress Model (ASM). In order to account for turbulent scalar fluxes, general gradient diffusion hypothesis has been used along with Boussinesq gradient diffusion hypothesis with a variable turbulent Schmidt number and additional empirical constant c3ε.To simulate buoyant flow domain a 2D vertical numerical model (WISE, Width Integrated Stratified Environments), based on Reynolds- Averaged Navier-Stokes (RANS) equations, has been deployed and the model has been further developed for different k-ε turbulence closures. Results are compared against measured laboratory values of a saline gravity current to explore the efficient turbulence model.
Abstract: In this paper, a robust statistics based filter to remove salt and pepper noise in digital images is presented. The function of the algorithm is to detect the corrupted pixels first since the impulse noise only affect certain pixels in the image and the remaining pixels are uncorrupted. The corrupted pixels are replaced by an estimated value using the proposed robust statistics based filter. The proposed method perform well in removing low to medium density impulse noise with detail preservation upto a noise density of 70% compared to standard median filter, weighted median filter, recursive weighted median filter, progressive switching median filter, signal dependent rank ordered mean filter, adaptive median filter and recently proposed decision based algorithm. The visual and quantitative results show the proposed algorithm outperforms in restoring the original image with superior preservation of edges and better suppression of impulse noise