Abstract: Understanding of how and where NOx formation
occurs in industrial burner is very important for efficient and clean
operation of utility burners. Also the importance of this problem is
mainly due to its relation to the pollutants produced by more burners
used widely of gas turbine in thermal power plants and glass and steel
industry.
In this article, a numerical model of an industrial burner operating
in MILD combustion is validated with experimental data.. Then
influence of air flow rate and air temperature on combustor
temperature profiles and NOX product are investigated. In order to
modification this study reports on the effects of fuel and air dilution
(with inert gases H2O, CO2, N2), and also influence of lean-premixed
of fuel, on the temperature profiles and NOX emission.
Conservation equations of mass, momentum and energy, and
transport equations of species concentrations, turbulence, combustion
and radiation modeling in addition to NO modeling equations were
solved together to present temperature and NO distribution inside the
burner.
The results shows that dilution, cause to a reduction in value of
temperature and NOX emission, and suppresses any flame
propagation inside the furnace and made the flame inside the furnace
invisible. Dilution with H2O rather than N2 and CO2 decreases further
the value of the NOX. Also with raise of lean-premix level, local
temperature of burner and the value of NOX product are decreases
because of premixing prevents local “hot spots" within the combustor
volume that can lead to significant NOx formation. Also leanpremixing
of fuel with air cause to amount of air in reaction zone is
reach more than amount that supplied as is actually needed to burn
the fuel and this act lead to limiting NOx formation
Abstract: Design and evaluation of reciprocating compressors
should include a pulsation study. The object is to ensure that
predicted pulsation levels meet guidelines to limit vibration, shaking
forces, noise, associated pressure drops, horsepower losses and
fabrication cost and time to acceptable levels. This paper explains
procedures and recommendations to select and size pulsation
suppression devices to obtain optimum arrangement in terms of
pulsation, vibration, shaking forces, performance, reliability, safety,
operation, maintenance and commercial conditions. Model and
advanced formulations for pulsation study are presented. The effect
of the full fluid dynamic model on the prediction of pulsation waves
and resulting frequency spectrum distributions are discussed.
Advanced and optimum methods of controlling pulsations are
highlighted. Useful recommendations and guidelines for pulsation
control, piping pulsation analysis, pulsation vessel design, shaking
forces, low pressure drop orifices, pulsation study report and devices
to mitigate pulsation and shaking problems are discussed.
Abstract: A new numerical method for solving the twodimensional,
steady, incompressible, viscous flow equations on a
Curvilinear staggered grid is presented in this paper. The proposed
methodology is finite difference based, but essentially takes
advantage of the best features of two well-established numerical
formulations, the finite difference and finite volume methods. Some
weaknesses of the finite difference approach are removed by
exploiting the strengths of the finite volume method. In particular,
the issue of velocity-pressure coupling is dealt with in the proposed
finite difference formulation by developing a pressure correction
equation in a manner similar to the SIMPLE approach commonly
used in finite volume formulations. However, since this is purely a
finite difference formulation, numerical approximation of fluxes is
not required. Results obtained from the present method are based on
the first-order upwind scheme for the convective terms, but the
methodology can easily be modified to accommodate higher order
differencing schemes.
Abstract: In this paper we present a novel technique for data
hiding in binary document images. We use the concept of entropy in
order to identify document specific least distortive areas throughout
the binary document image. The document image is treated as any
other image and the proposed method utilizes the standard document
characteristics for the embedding process. Proposed method
minimizes perceptual distortion due to embedding and allows
watermark extraction without the requirement of any side information
at the decoder end.
Abstract: In this paper, parallel interface for microprocessor
trainer was implemented. A programmable parallel–port device such
as the IC 8255A is initialized for simple input or output and for
handshake input or output by choosing kinds of modes. The hardware
connections and the programs can be used to interface
microprocessor trainer and a personal computer by using IC 8255A.
The assembly programs edited on PC-s editor can be downloaded to
the trainer.
Abstract: The problem discussed in this paper involves packing fresh fish fileet of the northern Cod into a standard square container. The fish is first cleaned and split and then collected on a belt ready to be stacked in a container. The aim of our work is to pack the fish into the container with constraints on the amount of overlap allowed for the fileets. The current focus is to design a packing cell that can be real-time and of practical use, while finding the optimal solution to the degree of overlap and minimise the unused space of the container.
Abstract: As a learning theory tries to borrow from science a framework to found its method, it shows paradoxes and paralysing contraddictions. This results, on one hand, from adopting a learning/teaching model as it were a mere “transfer of data" (mechanical learning approach), and on the other hand from borrowing the complexity theory (an indeterministic and non-linear model), that risks to vanish every educational effort. This work is aimed at describing existing criticism, unveiling the antinomic nature of such paradoxes, focussing on a view where neither the mechanical learning perspective nor the chaotic and nonlinear model can threaten and jeopardize the educational work. Author intends to go back over the steps that led to these paradoxes and to unveil their antinomic nature. Actually this could serve the purpose to explain some current misunderstandings about the real usefulness of Ict within the youth-s learning process and growth.
Abstract: The numerical simulation of the slip effect via
vicoelastic fluid for 4:1 contraction problem is investigated with
regard to kinematic behaviors of streamlines and stress tensor by
models of the Navier-Stokes and Oldroyd-B equations. Twodimensional
spatial reference system of incompressible creeping flow
with and without slip velocity is determined and the finite element
method of a semi-implicit Taylor-Galerkin pressure-correction is
applied to compute the problem of this Cartesian coordinate system
including the schemes of velocity gradient recovery method and the
streamline-Upwind / Petrov-Galerkin procedure. The slip effect at
channel wall is added to calculate after each time step in order to
intend the alteration of flow path. The result of stress values and the
vortices are reduced by the optimum slip coefficient of 0.1 with near
the outcome of analytical solution.
Abstract: A laboratory set-up was designed to survey the
effectiveness of UV/O3 advanced oxidation process (AOP) for the
removal of Carbaryl from polluted water in batch reactor. The study
was carried out by UV/O3 process for water samples containing 1 to
20 mg/L of Carbaryl in distilled water. Also the range of drinking
water resources adjusted in synthetic water and effects of contact
time, pH and Carbaryl concentration were studied. The residual
pesticide concentration was determined by applying high
performance liquid chromatography (HPLC). The results indicated
that increasing of retention time and pH, enhances pesticide removal
efficiency. The removal efficiency has been affected by pesticide
initial concentration. Samples with low pesticide concentration
showed a remarkable removal efficiency compared to the samples
with high pesticide concentration. AOP method showed the removal
efficiencies of 80% to 100%. Although process showed high
performance for removal of pesticide from water samples, this
process has different disadvantages including complication,
intolerability, difficulty of maintenance and equipmental and
structural requirements.
Abstract: There is currently intensive debate in Alberta,
Canada, regarding rural to urban water reallocation. This paper
explores the demographic and attitudinal influences that are
associated with the acceptance of water reallocation policies and
whether such acceptance differs between urban and rural residents.
We investigate three policy orientations in regards to water policies:
i) government intervention; ii) environmental protection; and iii)
protecting irrigators- water rights. We find that urban dwellers are
more likely to favour government intervention while rural dwellers
are more likely to support policies that aim at protecting irrigators-
water rights. While urban dwellers are also more likely to favour
environmental protection, the difference is not statistically
significant. We also find that other factors have a significant impact
on policy choice irrespective of residence such as demographic and
socioeconomic factors as well as the values people hold toward water
and the environment.
Abstract: This paper proposes a new decision making structure
to determine the appropriate product delivery strategy for different products in a manufacturing system among make-to-stock, make-toorder,
and hybrid strategy. Given product delivery strategies for all products in the manufacturing system, the position of the Order
Penetrating Point (OPP) can be located regarding the delivery strategies among which location of OPP in hybrid strategy is a
cumbersome task. In this regard, we employ analytic network process, because there are varieties of interrelated driving factors
involved in choosing the right location. Moreover, the proposed structure is augmented with fuzzy sets theory in order to cope with
the uncertainty of judgments. Finally, applicability of the proposed structure is proven in practice through a real industrial case company.
The numerical results demonstrate the efficiency of the proposed decision making structure in order partitioning and OPP location.
Abstract: In recent five decades, textured yarns of polyester fiber produced by false twist method are the most
important and mass-produced manmade fibers. There are
many parameters of cross section which affect the physical and mechanical properties of textured yarns. These parameters
are surface area, perimeter, equivalent diameter, large
diameter, small diameter, convexity, stiffness, eccentricity, and hydraulic diameter. These parameters were evaluated by
digital image processing techniques. To find trends between production criteria and evaluated parameters of cross section, three criteria of production line have been adjusted and different types of yarns were produced. These criteria are
temperature, drafting ratio, and D/Y ratio. Finally the relations between production criteria and cross section parameters were
considered. The results showed that the presented technique can recognize and measure the parameters of fiber cross section in acceptable accuracy. Also, the optimum condition
of adjustments has been estimated from results of image analysis evaluation.
Abstract: This paper deals with the application for contentbased
image retrieval to extract color feature from natural images
stored in the image database by segmenting the image through
clustering. We employ a class of nonparametric techniques in which
the data points are regarded as samples from an unknown probability
density. Explicit computation of the density is avoided by using the
mean shift procedure, a robust clustering technique, which does not
require prior knowledge of the number of clusters, and does not
constrain the shape of the clusters. A non-parametric technique for
the recovery of significant image features is presented and
segmentation module is developed using the mean shift algorithm to
segment each image. In these algorithms, the only user set parameter
is the resolution of the analysis and either gray level or color images
are accepted as inputs. Extensive experimental results illustrate
excellent performance.
Abstract: Automatic keyphrase extraction is useful in efficiently
locating specific documents in online databases. While several
techniques have been introduced over the years, improvement on
accuracy rate is minimal. This research examines attribute scores for
author-supplied keyphrases to better understand how the scores affect
the accuracy rate of automatic keyphrase extraction. Five attributes
are chosen for examination: Term Frequency, First Occurrence, Last
Occurrence, Phrase Position in Sentences, and Term Cohesion
Degree. The results show that First Occurrence is the most reliable
attribute. Term Frequency, Last Occurrence and Term Cohesion
Degree display a wide range of variation but are still usable with
suggested tweaks. Only Phrase Position in Sentences shows a totally
unpredictable pattern. The results imply that the commonly used
ranking approach which directly extracts top ranked potential phrases
from candidate keyphrase list as the keyphrases may not be reliable.
Abstract: In this paper, we propose the pre-processor based on
the Evidence Supporting Measure of Similarity (ESMS) filter and also
propose the unified fusion approach (UFA) based on the general
fusion machine coupled with ESMS filter, which improve the
correctness and precision of information fusion in any fields of
application. Here we mainly apply the new approach to Simultaneous
Localization And Mapping (SLAM) of Pioneer II mobile robots. A
simulation experiment was performed, where an autonomous virtual
mobile robot with sonar sensors evolves in a virtual world map with
obstacles. By comparing the result of building map according to the
general fusion machine (here DSmT-based fusing machine and
PCR5-based conflict redistributor considereded) coupling with ESMS
filter and without ESMS filter, it shows the benefit of the selection of
the sources as a prerequisite for improvement of the information
fusion, and also testifies the superiority of the UFA in dealing with
SLAM.
Abstract: Acoustic Imaging based sound localization using microphone
array is a challenging task in digital-signal processing.
Discrete Fourier transform (DFT) based near-field acoustical holography
(NAH) is an important acoustical technique for sound source
localization and provide an efficient solution to the ill-posed problem.
However, in practice, due to the usage of small curtailed aperture
and its consequence of significant spectral leakage, the DFT could
not reconstruct the active-region-of-sound (AROS) effectively, especially
near the edges of aperture. In this paper, we emphasize the
fundamental problems of DFT-based NAH, provide a solution to
spectral leakage effect by the extrapolation based on linear predictive
coding and 2D Tukey windowing. This approach has been tested to
localize the single and multi-point sound sources. We observe that
incorporating extrapolation technique increases the spatial resolution,
localization accuracy and reduces spectral leakage when small curtail
aperture with a lower number of sensors accounts.
Abstract: In this study it is aimed to determine the level of preservice teachers- computer phobia. Whether or not computer phobia meaningfully varies statistically according to gender and computer experience has been tested in the study. The study was performed on 430 pre-service teachers at the Education Faculty in Rize/Turkey. Data in the study were collected through the Computer Phobia Scale consisting of the “Personal Knowledge Questionnaire", “Computer Anxiety Rating Scale", and “Computer Thought Survey". In this study, data were analyzed with statistical processes such as t test, and correlation analysis. According to results of statistical analyses, computer phobia of male pre-service teachers does not statistically vary depending on their gender. Although male preservice teachers have higher computer anxiety scores, they have lower computer thought scores. It was also observed that there is a negative and intensive relation between computer experience and computer anxiety. Meanwhile it was found out that pre-service teachers using computer regularly indicated lower computer anxiety. Obtained results were tried to be discussed in terms of the number of computer classes in the Education Faculty curriculum, hours of computer class and the computer availability of student teachers.
Abstract: This article proposes a novel Pareto-based multiobjective
meta-heuristic algorithm named non-dominated ranking
genetic algorithm (NRGA) to solve multi-facility location-allocation
problem. In NRGA, a fitness value representing rank is assigned to
each individual of the population. Moreover, two features ranked
based roulette wheel selection including select the fronts and choose
solutions from the fronts, are utilized. The proposed solving
methodology is validated using several examples taken from the
specialized literature. The performance of our approach shows that
NRGA algorithm is able to generate true and well distributed Pareto
optimal solutions.
Abstract: In this paper we use data mining techniques to investigate factors that contribute significantly to enhancing the risk of acute coronary syndrome. We assume that the dependent variable is diagnosis – with dichotomous values showing presence or absence of disease. We have applied binary regression to the factors affecting the dependent variable. The data set has been taken from two different cardiac hospitals of Karachi, Pakistan. We have total sixteen variables out of which one is assumed dependent and other 15 are independent variables. For better performance of the regression model in predicting acute coronary syndrome, data reduction techniques like principle component analysis is applied. Based on results of data reduction, we have considered only 14 out of sixteen factors.
Abstract: In this study, solid phase micro-extraction (SPME)
was optimized to improve the sensitivity and accuracy in
formaldehyde determination for plywood panels. Further work has
been carried out to compare the newly developed technique with
existing method which reacts formaldehyde collected in desiccators
with acetyl acetone reagent (DC-AA). In SPME, formaldehyde was
first derivatized with O-(2,3,4,5,6 pentafluorobenzyl)-hydroxylamine
hydrochloride (PFBHA) and analysis was then performed by gas
chromatography in combination with mass spectrometry (GC-MS).
SPME data subjected to various wood species gave satisfactory
results, with relative standard deviations (RSDs) obtained in the
range of 3.1-10.3%. It was also well correlated with DC values,
giving a correlation coefficient, RSQ, of 0.959. The quantitative
analysis of formaldehyde by SPME was an alternative in wood
industry with great potential