Abstract: In this paper, an improvement of PDLZW implementation
with a new dictionary updating technique is proposed. A
unique dictionary is partitioned into hierarchical variable word-width
dictionaries. This allows us to search through dictionaries in parallel.
Moreover, the barrel shifter is adopted for loading a new input string
into the shift register in order to achieve a faster speed. However,
the original PDLZW uses a simple FIFO update strategy, which is
not efficient. Therefore, a new window based updating technique
is implemented to better classify the difference in how often each
particular address in the window is referred. The freezing policy
is applied to the address most often referred, which would not be
updated until all the other addresses in the window have the same
priority. This guarantees that the more often referred addresses would
not be updated until their time comes. This updating policy leads
to an improvement on the compression efficiency of the proposed
algorithm while still keep the architecture low complexity and easy
to implement.
Abstract: Stochastic modeling of network traffic is an area of
significant research activity for current and future broadband
communication networks. Multimedia traffic is statistically
characterized by a bursty variable bit rate (VBR) profile. In this
paper, we develop an improved model for uniform activity level
video sources in ATM using a doubly stochastic autoregressive
model driven by an underlying spatial point process. We then
examine a number of burstiness metrics such as the peak-to-average
ratio (PAR), the temporal autocovariance function (ACF) and the
traffic measurements histogram. We found that the former measure is
most suitable for capturing the burstiness of single scene video
traffic. In the last phase of this work, we analyse statistical
multiplexing of several constant scene video sources. This proved,
expectedly, to be advantageous with respect to reducing the
burstiness of the traffic, as long as the sources are statistically
independent. We observed that the burstiness was rapidly
diminishing, with the largest gain occuring when only around 5
sources are multiplexed. The novel model used in this paper for
characterizing uniform activity video was thus found to be an
accurate model.
Abstract: Experiments were carried out to evaluate the
influence of the addition of hydrogen to the inlet air on the
performance of a single cylinder direct injection diesel engine.
Hydrogen was injected in the inlet manifold. The addition of
hydrogen was done on energy replacement basis. It was found that
the addition of hydrogen improves the combustion process due to
superior combustion characteristics of hydrogen in comparison to
conventional diesel fuels. It was also found that 10% energy
replacement improves the engine thermal efficiency by about 40%
and reduces the sfc by about 35% however the volumetric efficiency
was reduced by about 35%.
Abstract: In this paper, a predator-prey model with Holling III type functional response is studied. It is interesting that the system is always uniformly persistent, which yields the existence of at least one positive periodic solutions for the corresponding periodic system. The result improves the corresponding ones in [11]. Moreover, an example is illustrated to verify the results by simulation.
Abstract: This paper analyses the unsteady, two-dimensional
stagnation point flow of an incompressible viscous fluid over a flat
sheet when the flow is started impulsively from rest and at the same
time, the sheet is suddenly stretched in its own plane with a velocity
proportional to the distance from the stagnation point. The partial
differential equations governing the laminar boundary layer forced
convection flow are non-dimensionalised using semi-similar
transformations and then solved numerically using an implicit finitedifference
scheme known as the Keller-box method. Results
pertaining to the flow and heat transfer characteristics are computed
for all dimensionless time, uniformly valid in the whole spatial region
without any numerical difficulties. Analytical solutions are also
obtained for both small and large times, respectively representing the
initial unsteady and final steady state flow and heat transfer.
Numerical results indicate that the velocity ratio parameter is found
to have a significant effect on skin friction and heat transfer rate at
the surface. Furthermore, it is exposed that there is a smooth
transition from the initial unsteady state flow (small time solution) to
the final steady state (large time solution).
Abstract: In this paper, the main principles of text-to-speech synthesis system are presented. Associated problems which arise when developing speech synthesis system are described. Used approaches and their application in the speech synthesis systems for Azerbaijani language are shown.
Abstract: Turbulence studies were made in the wake of a rotating
circular cylinder in a uniform free stream. The interest was to
examine the turbulence properties at the suppression of periodicity in
vortex formation process. An experimental study of the turbulent near
wake of a rotating circular cylinder was made at a Reynolds number
of 9000 for velocity ratios, λ between 0 and 2.7. Hot-wire
anemometry and particle image velocimetry results indicate that the
rotation of the cylinder causes significant changes in the vortical
activities. The turbulence quantities are getting smaller as λ increases
due to suppression of coherent vortex structures.
Abstract: Liposomal magnetofection is a simple, highly efficient
technology for cell transfection, demonstrating better outcome than a
number of other common gene delivery methods. However,
aggregate complexes distribution over the cell surface is non-uniform
due to the gradient of the permanent magnetic field. The aim of this
study was to estimate the efficiency of liposomal magnetofection for
prostate carcinoma PC3 cell line using newly designed device,
“DynaFECTOR", ensuring magnetofection in a dynamic gradient
magnetic field. Liposomal magnetofection in a dynamic gradient
magnetic field demonstrated the highest transfection efficiency for
PC3 cells – it increased for 21% in comparison with liposomal
magnetofection and for 42% in comparison with lipofection alone.
The optimal incubation time under dynamic magnetic field for PC3
cell line was 5 minutes and the optimal rotation frequency of
magnets – 5 rpm. The new approach also revealed lower cytotoxic
effect to cells than liposomal magnetofection.
Abstract: We numerically study the three-dimensional
magnetohydrodynamics (MHD) stability of oscillatory natural
convection flow in a rectangular cavity, with free top surface, filled
with a liquid metal, having an aspect ratio equal to A=L/H=5, and
subjected to a transversal temperature gradient and a uniform
magnetic field oriented in x and z directions. The finite volume
method was used in order to solve the equations of continuity,
momentum, energy, and potential. The stability diagram obtained in
this study highlights the dependence of the critical value of the
Grashof number Grcrit , with the increase of the Hartmann number
Ha for two orientations of the magnetic field. This study confirms
the possibility of stabilization of a liquid metal flow in natural
convection by application of a magnetic field and shows that the
flow stability is more important when the direction of magnetic field
is longitudinal than when the direction is transversal.
Abstract: Microwave energy can be used for drying purpose. It is unique process. It is distinctly different from conventional drying process. It is advantageous over conventional drying / heating processes. When microwave energy is used for drying purpose, the process can be accelerated with a better control to achieve uniform heating, more conversion efficiency, selective drying and ultimately improved product quality of the output. Also, less floor space and compact system are the added advantages. Existing low power microwave drying system is to be modified with suitable applicator. Appropriate sensors are to be used to measure parameters like moisture, temperature, weight of sample. Suitable high tech controller is to be used to control microwave power continuously from minimum to maximum. Phase - controller, cycle - controller and PWM - controller are some of the advanced power control techniques. It has been proposed to work on turmeric using high-tech phase controller to control the microwave power conveniently. The drying of turmeric with microwave energy employing phase controller gives better results as formulated in this paper and hence new approach of processing turmeric will open future doors of profit making to allied industries and the farmers.
Abstract: Infrared focal plane arrays (IRFPA) sensors, due to
their high sensitivity, high frame frequency and simple structure, have
become the most prominently used detectors in military applications.
However, they suffer from a common problem called the fixed pattern
noise (FPN), which severely degrades image quality and limits the
infrared imaging applications. Therefore, it is necessary to perform
non-uniformity correction (NUC) on IR image. The algorithms of
non-uniformity correction are classified into two main categories, the
calibration-based and scene-based algorithms. There exist some
shortcomings in both algorithms, hence a novel non-uniformity
correction algorithm based on non-linear fit is proposed, which
combines the advantages of the two algorithms. Experimental results
show that the proposed algorithm acquires a good effect of NUC with
a lower non-uniformity ratio.
Abstract: The main goal of data mining is to extract accurate, comprehensible and interesting knowledge from databases that may be considered as large search spaces. In this paper, a new, efficient type of Genetic Algorithm (GA) called uniform two-level GA is proposed as a search strategy to discover truly interesting, high-level prediction rules, a difficult problem and relatively little researched, rather than discovering classification knowledge as usual in the literatures. The proposed method uses the advantage of uniform population method and addresses the task of generalized rule induction that can be regarded as a generalization of the task of classification. Although the task of generalized rule induction requires a lot of computations, which is usually not satisfied with the normal algorithms, it was demonstrated that this method increased the performance of GAs and rapidly found interesting rules.
Abstract: The focal spot of a high intensity focused ultrasound
transducer is small. To heat a large target volume, multiple treatment spots are required. If the power of each treatment spot is fixed, it could
results in insufficient heating of initial spots and over-heating of later ones, which is caused by the thermal diffusion. Hence, to produce a
uniform heated volume, the delivered energy of each treatment spot
should be properly adjusted. In this study, we proposed an iterative, extrapolation technique to adjust the required ultrasound energy of
each treatment spot. Three different scanning pathways were used to evaluate the performance of this technique. Results indicate that by using the proposed technique, uniform heating volume could be obtained.
Abstract: In this research, several physical and chemical properties and mineral contents of Russion olive (Elaeagnus angustifolia L.) fruit grown in Turkey were determined. In the fruit, length, width, thickness, weight were determined as 2.866cm, 1.880cm, 1.870cm, 2.90g; total soluble solids and colour were determined as 13.14% and S33O60Y99, respectively. In the seed, mean length, width, thickness, and weight were found to be 2.420cm, 0.508cm, 0.503cm, and 0.38g, respectively. In the fruit, 28 minerals (K, P, Ca, Na, Mg, S, Pb, Ba, Ga, As, In, Ti, Fe, Mn, Zn, Cu, Co, B, Cd, Se, Li, Sr, Al, Ni, Ag, V, Cr, Bi) were analyzed and 19 minerals were present at detectable levels. Russion olive fruit was richest in potassium (10296.906ppm), Mg (762.314ppm), P (609.694ppm), Ca (547.647ppm), and Na (222.749ppm).
Abstract: In this paper an analytical crack propagation scenario
is proposed which assumes that a crack propagates in the tooth root in
both the crack depth direction and the tooth width direction, and
which is more reasonable and realistic for non-uniform load
distribution cases than the other presented scenarios. An analytical
approach is used for quantifying the loss of time-varying gear mesh
stiffness with the presence of crack propagation in the gear tooth root.
The proposed crack propagation scenario can be applied for crack
propagation modelling and monitoring simulation, but further
research is required for comparison and evaluation of all the
presented crack propagation scenarios from the condition monitoring
point of view.
Abstract: Canola is a specific edible type of rapeseed, developed
in the 1970s, which contains about 40 percent oil. This research was
carried out to determine the yield and some quality characteristics of
some winter canola cultivars during the 2010-2011 vegetation period
in Central Anatolia of Turkey. In this research; Oase, Dante,
Californium, Excalibur, Elvis, ES Hydromel, Licord, Orkan, Vectra,
Nelson, Champlain and NK Petrol winter canola varieties were used
as material. The field experiment was set up in a “Randomized
Complete Block Design” with three replications on 21 September
2010. In this research; seed yield, oil content, protein content, oil
yield and protein yield were examined.
As a result of this research; seed yield, oil content, oil yield and
protein yield (except protein content) were significant differences
between the cultivars. The highest seed yield (6348 kg ha-1) was
obtained from the NK Petrol, while the lowest seed yield (3949 kg
ha-1) was determined from the Champlain cultivar was obtained. The
highest oil content (46.73%) was observed from Oase and the lowest
value was obtained from Vectra (41.87%) cultivar. The highest oil
yield (2950 kg ha-1) was determined from NK Petrol while the least
value (1681 kg ha-1) was determined from Champlain cultivar. The
highest protein yield (1539.3 kg ha-1) was obtained from NK Petrol
and the lowest protein yield (976.5 kg ha-1) was obtained from
Champlain cultivar.
The main purpose of the cultivation of oil crops, to increase the
yield of oil per unit area. According the result of this research, NK
Petrol cultivar which ranks first with regard to both seed yield and oil
yield between cultivars as the most suitable winter canola cultivar of
local conditions.
Abstract: Induction machine models used for steady-state and
transient analysis require machine parameters that are usually
considered design parameters or data. The knowledge of induction
machine parameters is very important for Indirect Field Oriented
Control (IFOC). A mismatched set of parameters will degrade the
response of speed and torque control. This paper presents an
improvement approach on rotor time constant adaptation in IFOC for
Induction Machines (IM). Our approach tends to improve the
estimation accuracy of the fundamental model for flux estimation.
Based on the reduced order of the IM model, the rotor fluxes and
rotor time constant are estimated using only the stator currents and
voltages. This reduced order model offers many advantages for real
time identification parameters of the IM.
Abstract: The influence of extrusion parameters on surface
quality and properties of AA6061+x% vol. SiC (x = 0; 2,5; 5; 7,5;10)
composites was discussed in this paper. The averages size of
AA6061 and SiC particles were 10.6 μm and 0.42 μm, respectively.
Two series of composites (I - compacts were preheated at extrusion
temperature through 0.5 h and cooled by water directly after process;
II - compacts were preheated through 3 hours and were not cooled)
were consolidated via powder metallurgy processing and extruded by
KoBo method. High values of density for both series of composites
were achieved. Better surface quality was observed for II series of
composites. Moreover, for these composites lower (compared to I
series) but more uniform strength properties over the cross-section of
the bar were noticed. Microstructure and Young-s modulus
investigations were made.
Abstract: It is essential to have a uniform and calm flow field
for a settling tank to have high performance. In general, the
recirculation zones always occurred in sedimentation tanks. The
presence of these regions may have different effects. The nonuniformity
of the velocity field, the short-circuiting at the surface and
the motion of the jet at the bed of the tank that occurs because of the
recirculation in the sedimentation layer, are affected by the geometry
of the tank. There are some ways to decrease the size of these dead
zones, which would increase the performance. One of the ways is to
use a suitable baffle configuration. In this study, the presence of
baffle with different position has been investigated by a finite volume
method, with VOF (Volume of Fluid) model. Besides, the k-ε
turbulence model is used in the numerical calculations. The results
indicate that the best position of the baffle is obtained when the
volume of the recirculation region is minimized or is divided to
smaller part and the flow field trend to be uniform in the settling
zone.
Abstract: This paper presents an innovative approach within the area of Group Decision Support System (GDSS) by using tools based on intelligent agents. It introduces iGDSS, a software platform for decision support and collaboration and an application of this platform - eCollaborative Decisions - for academic environment, all these developed within a framework of a research project.