Abstract: The article deals with the relation between rainfall in selected months and subsequent weed infestation of spring barley. The field experiment was performed at Mendel University agricultural enterprise in Žabčice, Czech Republic. Weed infestation was measured in spring barley vegetation in years 2004 to 2012. Barley was grown in three tillage variants: conventional tillage technology (CT), minimization tillage technology (MT), and no tillage (NT). Precipitation was recorded in one-day intervals. Monthly precipitation was calculated from the measured values in the months of October through to April. The technique of canonical correspondence analysis was applied for further statistical processing. 41 different species of weeds were found in the course of the 9-year monitoring period. The results clearly show that precipitation affects the incidence of most weed species in the selected months, but acts differently in the monitored variants of tillage technologies.
Abstract: Burnishing is a method of finishing and hardening
machined parts by plastic deformation of the surface. Experimental
work based on central composite second order rotatable design has
been carried out on a lathe machine to establish the effects of ball
burnishing parameters on the surface roughness of brass material.
Analysis of the results by the analysis of variance technique and the
F-test show that the parameters considered, have significant effects
on the surface roughness.
Abstract: The major goal in defining and examining game
scenarios is to find good strategies as solutions to the game. A
plausible solution is a recommendation to the players on how to play
the game, which is represented as strategies guided by the various
choices available to the players. These choices invariably compel the
players (decision makers) to execute an action following some
conscious tactics. In this paper, we proposed a refinement-based
heuristic as a machine learning technique for human-like decision
making in playing Ayo game. The result showed that our machine
learning technique is more adaptable and more responsive in making
decision than human intelligence. The technique has the advantage
that a search is astutely conducted in a shallow horizon game tree.
Our simulation was tested against Awale shareware and an appealing
result was obtained.
Abstract: In this paper, the robust exponential stability problem of discrete-time uncertain stochastic neural networks with timevarying delays is investigated. By introducing a new augmented Lyapunov function, some delay-dependent stable results are obtained in terms of linear matrix inequality (LMI) technique. Compared with some existing results in the literature, the conservatism of the new criteria is reduced notably. Three numerical examples are provided to demonstrate the less conservatism and effectiveness of the proposed method.
Abstract: Three-dimensional simulation of harmonic up
generation in free electron laser amplifier operating simultaneously
with a cold and relativistic electron beam is presented in steady-state
regime where the slippage of the electromagnetic wave with respect
to the electron beam is ignored. By using slowly varying envelope
approximation and applying the source-dependent expansion to wave
equations, electromagnetic fields are represented in terms of the
Hermit Gaussian modes which are well suited for the planar wiggler
configuration. The electron dynamics is described by the fully threedimensional
Lorentz force equation in presence of the realistic planar
magnetostatic wiggler and electromagnetic fields. A set of coupled
nonlinear first-order differential equations is derived and solved
numerically. The fundamental and third harmonic radiation of the
beam is considered. In addition to uniform beam, prebunched
electron beam has also been studied. For this effect of sinusoidal
distribution of entry times for the electron beam on the evolution of
radiation is compared with uniform distribution. It is shown that
prebunching reduces the saturation length substantially. For
efficiency enhancement the wiggler is set to decrease linearly when
the radiation of the third harmonic saturates. The optimum starting
point of tapering and the slope of radiation in the amplitude of
wiggler are found by successive run of the code.
Abstract: Most of the commonly used blind equalization algorithms are based on the minimization of a nonconvex and nonlinear cost function and a neural network gives smaller residual error as compared to a linear structure. The efficacy of complex valued feedforward neural networks for blind equalization of linear and nonlinear communication channels has been confirmed by many studies. In this paper we present two neural network models for blind equalization of time-varying channels, for M-ary QAM and PSK signals. The complex valued activation functions, suitable for these signal constellations in time-varying environment, are introduced and the learning algorithms based on the CMA cost function are derived. The improved performance of the proposed models is confirmed through computer simulations.
Abstract: The beneficial effects of Si are mainly associated with
its high deposition in plant tissue and enhancing their strength and
rigidity. We investigated the role of Si against cadmium stress in
(Echium C) in house green condition. When the seventh leaves was
be appeared, plants were pretreated with five levels of Si: 0, 0.2, 0.5,
0.7and 1.5 mM Si (as sodium trisilicate, Na2(SiO2)3) and after that
plants were treated with two levels of Cd (30 and 90 mM). The
effects of Silicon and Cd were investigated on some physiological
and biochemical parameters such as: lipid peroxidation
(malondialdehyde (MDA) and other aldehydes, antocyanin and
flavonoid content. Our results showed that Cd significantly increased
MDA, other aldehydes, antocyanin and flavonoids content in
Echium and silicon offset the negative effect and increased tolerance
of Echium against Cd stress. From this results we concluded that Si
increase membrane integrity and antioxidative ability in this plant
against cd stress.
Abstract: In this paper, the differential quadrature method is applied to simulate natural convection in an inclined cubic cavity using velocity-vorticity formulation. The numerical capability of the present algorithm is demonstrated by application to natural convection in an inclined cubic cavity. The velocity Poisson equations, the vorticity transport equations and the energy equation are all solved as a coupled system of equations for the seven field variables consisting of three velocities, three vorticities and temperature. The coupled equations are simultaneously solved by imposing the vorticity definition at boundary without requiring the explicit specification of the vorticity boundary conditions. Test results obtained for an inclined cubic cavity with different angle of inclinations for Rayleigh number equal to 103, 104, 105 and 106 indicate that the present coupled solution algorithm could predict the benchmark results for temperature and flow fields. Thus, it is convinced that the present formulation is capable of solving coupled Navier-Stokes equations effectively and accurately.
Abstract: Flight management system (FMS) is a specialized
computer system that automates a wide variety of in-flight tasks,
reducing the workload on the flight crew to the point that modern
aircraft no longer carry flight engineers or navigators. The primary
function of FMS is to perform the in-flight management of the flight
plan using various sensors (such as GPS and INS often backed up by
radio navigation) to determine the aircraft's position. From the
cockpit FMS is normally controlled through a Control Display Unit
(CDU) which incorporates a small screen and keyboard or touch
screen. This paper investigates the performance of GPS/ INS
integration techniques in which the data fusion process is done using
Kalman filtering. This will include the importance of sensors
calibration as well as the alignment of the strap down inertial
navigation system. The limitations of the inertial navigation systems
are investigated in order to understand why INS sometimes is
integrated with other navigation aids and not just operating in standalone
mode. Finally, both the loosely coupled and tightly coupled
configurations are analyzed for several types of situations and
operational conditions.
Abstract: Can biometrics do what everyone is expecting it will?
And more importantly, should it be doing it? Biometrics is the
buzzword “on the mouth" of everyone, who are trying to use this
technology in a variety of applications. But all this “hype" about
biometrics can be dangerous without a careful evaluation of the real
needs of each application. In this paper I-ll try to focus on the
dangers of using the right technology at the right time in the wrong
place.
Abstract: The governing two-dimensional equations of a heterogeneous material composed of a fluid (allowed to flow in the absence of acoustic excitations) and a crystalline piezoelectric cubic solid stacked one-dimensionally (along the z direction) are derived and special emphasis is given to the discussion of acoustic group velocity for the structure as a function of the wavenumber component perpendicular to the stacking direction (being the x axis). Variations in physical parameters with y are neglected assuming infinite material homogeneity along the y direction and the flow velocity is assumed to be directed along the x direction. In the first part of the paper, the governing set of differential equations are derived as well as the imposed boundary conditions. Solutions are provided using Hamilton-s equations for the wavenumber vs. frequency as a function of the number and thickness of solid layers and fluid layers in cases with and without flow (also the case of a position-dependent flow in the fluid layer is considered). In the first part of the paper, emphasis is given to the small-frequency case. Boundary conditions at the bottom and top parts of the full structure are left unspecified in the general solution but examples are provided for the case where these are subject to rigid-wall conditions (Neumann boundary conditions in the acoustic pressure). In the second part of the paper, emphasis is given to the general case of larger frequencies and wavenumber-frequency bandstructure formation. A wavenumber condition for an arbitrary set of consecutive solid and fluid layers, involving four propagating waves in each solid region, is obtained again using the monodromy matrix method. Case examples are finally discussed.
Abstract: Diabetes mellitus (DM) is frequently characterized by
autonomic nervous dysfunction. Analysis of heart rate variability
(HRV) has become a popular noninvasive tool for assessing the
activities of autonomic nervous system (ANS). In this paper, changes
in ANS activity are quantified by means of frequency and time
domain analysis of R-R interval variability. Electrocardiograms
(ECG) of 16 patients suffering from DM and of 16 healthy volunteers
were recorded. Frequency domain analysis of extracted normal to
normal interval (NN interval) data indicates significant difference in
very low frequency (VLF) power, low frequency (LF) power and
high frequency (HF) power, between the DM patients and control
group. Time domain measures, standard deviation of NN interval
(SDNN), root mean square of successive NN interval differences
(RMSSD), successive NN intervals differing more than 50 ms (NN50
Count), percentage value of NN50 count (pNN50), HRV triangular
index and triangular interpolation of NN intervals (TINN) also show
significant difference between the DM patients and control group.
Abstract: A kinetic model for propane dehydrogenation in an
industrial moving bed reactor is developed based on the reported
reaction scheme. The kinetic parameters and activity constant are
fine tuned with several sets of balanced plant data. Plant data at
different operating conditions is applied to validate the model and
the results show a good agreement between the model
predictions and plant observations in terms of the amount of main
product, propylene produced. The simulation analysis of key
variables such as inlet temperature of each reactor (Tinrx) and
hydrogen to total hydrocarbon ratio (H2/THC) affecting process
performance is performed to identify the operating condition to
maximize the production of propylene. Within the range of operating
conditions applied in the present studies, the operating condition to
maximize the propylene production at the same weighted average
inlet temperature (WAIT) is ΔTinrx1= -2, ΔTinrx2= +1, ΔTinrx3= +1 ,
ΔTinrx4= +2 and ΔH2/THC= -0.02. Under this condition, the surplus
propylene produced is 7.07 tons/day as compared with base case.
Abstract: A series of experiments were carried out to study
unsteady behavior of the flow field as well as the boundary layer of
an airfoil oscillating in plunging motion in a subsonic wind tunnel.
The measurements involved surface pressure distribution
complimented with surface-mounted hot-films. The effect of leadingedge
roughness that simulates surface irregularities on the wind
turbine blades was also studied on variations of aerodynamic loads
and boundary layer behavior.
Abstract: Insufficient Quality of Service (QoS) of Voice over
Internet Protocol (VoIP) is a growing concern that has lead the need
for research and study. In this paper we investigate the performance
of VoIP and the impact of resource limitations on the performance of
Access Networks. The impact of VoIP performance in Access
Networks is particularly important in regions where Internet
resources are limited and the cost of improving these resources is
prohibitive. It is clear that perceived VoIP performance, as measured
by mean opinion score [2] in experiments, where subjects are asked
to rate communication quality, is determined by end-to-end delay on
the communication path, delay variation, packet loss, echo, the
coding algorithm in use and noise. These performance indicators can
be measured and the affect in the Access Network can be estimated.
This paper investigates the congestion in the Access Network to the
overall performance of VoIP services with the presence of other
substantial uses of internet and ways in which Access Networks can
be designed to improve VoIP performance. Methods for analyzing
the impact of the Access Network on VoIP performance will be
surveyed and reviewed. This paper also considers some approaches
for improving performance of VoIP by carrying out experiments
using Network Simulator version 2 (NS2) software with a view to
gaining a better understanding of the design of Access Networks.
Abstract: Protein 3D structure prediction has always been an
important research area in bioinformatics. In particular, the
prediction of secondary structure has been a well-studied research
topic. Despite the recent breakthrough of combining multiple
sequence alignment information and artificial intelligence algorithms
to predict protein secondary structure, the Q3 accuracy of various
computational prediction algorithms rarely has exceeded 75%. In a
previous paper [1], this research team presented a rule-based method
called RT-RICO (Relaxed Threshold Rule Induction from Coverings)
to predict protein secondary structure. The average Q3 accuracy on
the sample datasets using RT-RICO was 80.3%, an improvement
over comparable computational methods. Although this demonstrated
that RT-RICO might be a promising approach for predicting
secondary structure, the algorithm-s computational complexity and
program running time limited its use. Herein a parallelized
implementation of a slightly modified RT-RICO approach is
presented. This new version of the algorithm facilitated the testing of
a much larger dataset of 396 protein domains [2]. Parallelized RTRICO
achieved a Q3 score of 74.6%, which is higher than the
consensus prediction accuracy of 72.9% that was achieved for the
same test dataset by a combination of four secondary structure
prediction methods [2].
Abstract: Current spectrums of a high power induction machine was calculated for the cases of full symmetry, static and dynamic eccentricity. The calculations involve integration of 93 electrical plus four mechanical ordinary differential equations. Electrical equations account for variable inductances affected by slotting and eccentricities. The calculations were followed by Fourier analysis of the stator currents in steady state operation. The paper presents the stator current spectrums in full symmetry, static and dynamic eccentricity cases, and demonstrates the harmonics present in each case. The effect of dynamic eccentricity is demonstrating via comparing the current spectrums related to dynamic eccentricity cases with the full symmetry one. The paper includes one case study, refers to dynamic eccentricity, to present the spectrum of the measured current and demonstrate the existence of the harmonics related to dynamic eccentricity. The zooms of current spectrums around the main slot harmonic zone are included to simplify the comparison and prove the existence of the dynamic eccentricity harmonics in both calculated and measured current spectrums.
Abstract: In recent times, the problem of Unsolicited Bulk
Email (UBE) or commonly known as Spam Email, has increased at a
tremendous growth rate. We present an analysis of survey based on
classifications of UBE in various research works. There are many
research instances for classification between spam and non-spam
emails but very few research instances are available for classification
of spam emails, per se. This paper does not intend to assert some
UBE classification to be better than the others nor does it propose
any new classification but it bemoans the lack of harmony on number
and definition of categories proposed by different researchers. The
paper also elaborates on factors like intent of spammer, content of
UBE and ambiguity in different categories as proposed in related
research works of classifications of UBE.
Abstract: This paper describes a one-dimensional numerical model for natural gas production from the dissociation of methane hydrate in hydrate-capped gas reservoir under depressurization and thermal stimulation. Some of the hydrate reservoirs discovered are overlying a free-gas layer, known as hydrate-capped gas reservoirs. These reservoirs are thought to be easiest and probably the first type of hydrate reservoirs to be produced. The mathematical equations that can be described this type of reservoir include mass balance, heat balance and kinetics of hydrate decomposition. These non-linear partial differential equations are solved using finite-difference fully implicit scheme. In the model, the effect of convection and conduction heat transfer, variation change of formation porosity, the effect of using different equations of state such as PR and ER and steam or hot water injection are considered. In addition distributions of pressure, temperature, saturation of gas, hydrate and water in the reservoir are evaluated. It is shown that the gas production rate is a sensitive function of well pressure.
Abstract: In the present paper, a numerical investigation has
been carried out to classify and clarify the effects of paramount
parameters on turbulent impinging slot jets. The effects of nozzle-s
exit turbulent intensity, distance between nozzle and impinging plate
are studied at Reynolds number 5000 and 20000. In addition, the
effect of Mach number that is varied between 0.3-0.8 at a constant
Reynolds number 133000 is investigated to elucidate the effect of
compressibility in impinging jet upon a flat plate. The wall that is
located at the same level with nozzle-s exit confines the flow. A
compressible finite volume solver is implemented for simulation the
flow behavior. One equation Spalart-Allmaras turbulent model is
used to simulate turbulent flow at this study. Assessment of the
Spalart-Allmaras turbulent model at high nozzle to plate distance,
and giving enough insights to characterize the effect of Mach number
at high Reynolds number for the complex impinging jet flow are the
remarkable results of this study.