Abstract: Tailor-welded Blanks (TWBs) are tailor made for
different complex component designs by welding multiple metal
sheets with different thicknesses, shapes, coatings or strengths prior
to forming. In this study the Hemispherical Die Stretching (HDS) test
(out-of-plane stretching) of TWBs were simulated via
ABAQUS/Explicit to obtain the Forming Limit Diagrams (FLDs) of
Stainless steel (AISI 304) laser welded blanks with different
thicknesses. Two criteria were used to detect the start of necking to
determine the FLD for TWBs and parent sheet metals. These two
criteria are the second derivatives of the major and thickness strains
that are given from the strain history of simulation. In the other word,
in these criteria necking starts when the second derivative of
thickness or major strain reaches its maximum. With having the time
of onset necking, one can measure the major and minor strains at the
critical area and determine the forming limit curve.
Abstract: Artemisinin is a potential antimalarial drug effective
against the multidrug resistant forms of Malarial Parasites. The
current production of artemisinin is insufficient to meet the global
demand. In the present study microbial biotransformation of
arteannuin B, a biogenetic precursor of artemisinin to the later has
been investigated. Screening studies carried out on several soil borne
microorganisms have yielded one novel species with the
bioconversion ability. Crude cell free extract of 72h old culture of the
isolate had shown the bioconversion activity. On incubation with the
substrate arteannuin B, crude cell free extract of the isolate had
shown a bioconversion of 18.54% to artemisinin on molar basis with
a specific activity of 0.18 units/mg.
Abstract: The nanotechnology based on epitaxial systems
includes single or arranged misfit dislocations. In general, whatever
is the type of dislocation or the geometry of the array formed by the
dislocations; it is important for experimental studies to know exactly
the stress distribution for which there is no analytical expression [1,
2]. This work, using a numerical analysis, deals with relaxation of
epitaxial layers having at their interface a periodic network of edge
misfit dislocations. The stress distribution is estimated by using
isotropic elasticity. The results show that the thickness of the two
sheets is a crucial parameter in the stress distributions and then in the
profile of the two sheets.
A comparative study between the case of single dislocation and
the case of parallel network shows that the layers relaxed better when
the interface is covered by a parallel arrangement of misfit.
Consequently, a single dislocation at the interface produces an
important stress field which can be reduced by inserting a parallel
network of dislocations with suitable periodicity.
Abstract: The High Voltage (HV) transmission mains into the community necessitate earthing design to ensure safety compliance of the system. Concrete poles are widely used within HV transmission mains; which could have an impact on the earth grid impedance and input impedance of the system from the fault point of view. This paper provides information on concrete pole earthing to enhance the split factor of the system; further, it discusses the deployment of concrete structures in high soil resistivity area to reduce the earth grid system of the plant. This paper introduces the cut off soil resistivity SC ρ when replacing timber poles with concrete ones.
Abstract: This paper presents the development of an active
vibration control using direct adaptive controller to suppress the
vibration of a flexible beam system. The controller is realized based
on linear parametric form. Differential evolution optimisation
algorithm is used to optimize the controller using single objective
function by minimizing the mean square error of the observed
vibration signal. Furthermore, an alternative approach is developed to
systematically search for the best controller model structure together
with it parameter values. The performance of the control scheme is
presented and analysed in both time and frequency domain.
Simulation results demonstrate that the proposed scheme is able to
suppress the unwanted vibration effectively.
Abstract: It is believed that continuously variable transmission (CVT) will dominate the automotive transmissions in the future. The most popular design is Van Doorne-s CVT with single metal pushing V-belt. However, it is only applicable to low power passenger cars because its major limitation is low torque capacity. Therefore, this research studies a novel dual-belt CVT system to overcome the limitation of traditional single-belt CVT, such that it can be applicable to the heavy-duty vehicles. This paper presents the mathematical model of the design and its experimental verification. Experimental and simulated results show that the model developed is valid and the proposed dual-belt CVT can really overcome the traditional limitation of single-belt Van Doorne-s CVT.
Abstract: In electronegative-electropositive gas mixtures plasma, at a total pressure varying in the range of ten to hundred Torr, the appearance of a quasi-mochromatization effect of the emitted radiation was reported. This radiation could be the result of the generating mechanisms at molecular level, which is the case of the excimer radiation but also at atomic level. Thus, in the last case, in (Ne+1%Ar/Xe+H2) gas mixtures plasma in a dielectric barrier discharge, this effect, called M-effect, consists in the reduction of the discharge emission spectrum practice at one single, strong spectral line with λ = 585.3 nm. The present paper is concerned with the characteristics comparative investigation of the principal reaction mechanisms involved in the quasi-monochromatization effect existence in the case of the excimer radiation, respectively of the Meffect. Also, the paper points out the role of the metastable electronegative atoms in the appearance of the monochromatization – effect at atomic level.
Abstract: E-services have significantly changed the way of
doing business in recent years. We can, however, observe poor use of
these services. There is a large gap between supply and actual eservices
usage. This is why we started a project to provide an
environment that will encourage the use of e-services. We believe
that only providing e-service does not automatically mean consumers
would use them. This paper shows the origins of our project and its
current position. We discuss the decision of using semantic web
technologies and their potential to improve e-services usage. We also
present current knowledge base and its real-world classification. In the paper, we discuss further work to be done in the project. Current
state of the project is promising.
Abstract: Biclustering is a very useful data mining technique for
identifying patterns where different genes are co-related based on a
subset of conditions in gene expression analysis. Association rules
mining is an efficient approach to achieve biclustering as in
BIMODULE algorithm but it is sensitive to the value given to its
input parameters and the discretization procedure used in the
preprocessing step, also when noise is present, classical association
rules miners discover multiple small fragments of the true bicluster,
but miss the true bicluster itself. This paper formally presents a
generalized noise tolerant bicluster model, termed as μBicluster. An
iterative algorithm termed as BIDENS based on the proposed model
is introduced that can discover a set of k possibly overlapping
biclusters simultaneously. Our model uses a more flexible method to
partition the dimensions to preserve meaningful and significant
biclusters. The proposed algorithm allows discovering biclusters that
hard to be discovered by BIMODULE. Experimental study on yeast,
human gene expression data and several artificial datasets shows that
our algorithm offers substantial improvements over several
previously proposed biclustering algorithms.
Abstract: The development of information and communication
technology, the increased use of the internet, as well as the effects of
the recession within the last years, have lead to the increased use of
cloud computing based solutions, also called on-demand solutions.
These solutions offer a large number of benefits to organizations as
well as challenges and risks, mainly determined by data visualization
in different geographic locations on the internet. As far as the specific
risks of cloud environment are concerned, data security is still
considered a peak barrier in adopting cloud computing. The present
study offers an approach upon ensuring the security of cloud data,
oriented towards the whole data life cycle. The final part of the study
focuses on the assessment of data security in the cloud, this
representing the bases in determining the potential losses and the
premise for subsequent improvements and continuous learning.
Abstract: Insulation used in transformer is mostly oil pressboard insulation. Insulation failure is one of the major causes of catastrophic failure of transformers. It is established that partial discharges (PD) cause insulation degradation and premature failure of insulation. Online monitoring of PDs can reduce the risk of catastrophic failure of transformers. There are different techniques of partial discharge measurement like, electrical, optical, acoustic, opto-acoustic and ultra high frequency (UHF). Being non invasive and non interference prone, acoustic emission technique is advantageous for online PD measurement. Acoustic detection of p.d. is based on the retrieval and analysis of mechanical or pressure signals produced by partial discharges. Partial discharges are classified according to the origin of discharges. Their effects on insulation deterioration are different for different types. This paper reports experimental results and analysis for classification of partial discharges using acoustic emission signal of laboratory simulated partial discharges in oil pressboard insulation system using three different electrode systems. Acoustic emission signal produced by PD are detected by sensors mounted on the experimental tank surface, stored on an oscilloscope and fed to computer for further analysis. The measured AE signals are analyzed using discrete wavelet transform analysis and wavelet packet analysis. Energy distribution in different frequency bands of discrete wavelet decomposed signal and wavelet packet decomposed signal is calculated. These analyses show a distinct feature useful for PD classification. Wavelet packet analysis can sort out any misclassification arising out of DWT in most cases.
Abstract: Cardiac pulse-related artifacts in the EEG recorded
simultaneously with fMRI are complex and highly variable. Their
effective removal is an unsolved problem. Our aim is to develop an
adaptive removal algorithm based on the matching pursuit (MP)
technique and to compare it to established methods using a visual
evoked potential (VEP). We recorded the VEP inside the static
magnetic field of an MR scanner (with artifacts) as well as in an
electrically shielded room (artifact free). The MP-based artifact
removal outperformed average artifact subtraction (AAS) and
optimal basis set removal (OBS) in terms of restoring the EEG field
map topography of the VEP. Subsequently, a dipole model was fitted
to the VEP under each condition using a realistic boundary element
head model. The source location of the VEP recorded inside the MR
scanner was closest to that of the artifact free VEP after cleaning
with the MP-based algorithm as well as with AAS. While none of the
tested algorithms offered complete removal, MP showed promising
results due to its ability to adapt to variations of latency, frequency
and amplitude of individual artifact occurrences while still utilizing a
common template.
Abstract: In this paper, an ultrasonic technique is proposed to
predict oil content in a fresh palm fruit. This is accomplished by
measuring the attenuation based on ultrasonic transmission mode.
Several palm fruit samples with known oil content by Soxhlet
extraction (ISO9001:2008) were tested with our ultrasonic
measurement. Amplitude attenuation data results for all palm samples
were collected. The Feedforward Neural Networks (FNNs) are
applied to predict the oil content for the samples. The Root Mean
Square Error (RMSE) and Mean Absolute Error (MAE) of the FNN
model for predicting oil content percentage are 7.6186 and 5.2287
with the correlation coefficient (R) of 0.9193.
Abstract: This paper present a new way to find the aerodynamic characteristic equation of missile for the numerical trajectories prediction more accurate. The goal is to obtain the polynomial equation based on two missile characteristic parameters, angle of attack (α ) and flight speed (╬¢ ). First, the understudied missile is modeled and used for flow computational model to compute aerodynamic force and moment. Assume that performance range of understudied missile where range -10< α
Abstract: The textile industry produces highly coloured
effluents containing polar and non-polar compounds. The textile mill
run by the Assam Polyester Co-operative Society Limited (APOL) is
situated at Rangia, about 55 km from Guwahati (26011' N, 91047' E)
in the northern bank of the river Brahmaputra, Assam (India). This
unit was commissioned in June 1988 and started commercial
production in November 1988. The installed capacity of the weaving
unit was 8000 m/day and that of the processing unit was 20,000
m/day. The mill has its own dyeing unit with a capacity of 1500-2000
kg/day. The western side of the mill consists of vast agricultural land
and the far northern and southern side of the mill has scattered human
population. The eastern side of the mill has a major road for
thoroughfare. The mill releases its effluents into the agricultural land
in the western side of the mill. The present study was undertaken to
assess the impact of the textile mill on surface soil quality in and
around the mill with particular reference to Cr, Mn, Ni and Zn.
Surface soil samples, collected along different directions at 200, 500
and 1000 m were digested and the metals were estimated with
Atomic Absorption Spectrophotometer. The metals were found in the
range of: Cr 50.9 – 105.0 mg kg-1, Mn 19.2- 78.6 mg kg-1, Ni 41.9 –
50.6 mg kg-1 and Zn 187.8 – 1095.8 mg kg-1. The study reveals
enrichment of Cr, Mn, Ni and Zn in the soil near the textile mill.
Abstract: This study investigates the performance of radial basis function networks (RBFN) in forecasting the monthly CO2 emissions of an electric power utility. We also propose a method for input variable selection. This method is based on identifying the general relationships between groups of input candidates and the output. The effect that each input has on the forecasting error is examined by removing all inputs except the variable to be investigated from its group, calculating the networks parameter and performing the forecast. Finally, the new forecasting error is compared with the reference model. Eight input variables were identified as the most relevant, which is significantly less than our reference model with 30 input variables. The simulation results demonstrate that the model with the 8 inputs selected using the method introduced in this study performs as accurate as the reference model, while also being the most parsimonious.
Abstract: On the basis of the linearized Phillips-Herffron model of a single-machine power system, a novel method for designing unified power flow controller (UPFC) based output feedback controller is presented. The design problem of output feedback controller for UPFC is formulated as an optimization problem according to with the time domain-based objective function which is solved by iteration particle swarm optimization (IPSO) that has a strong ability to find the most optimistic results. To ensure the robustness of the proposed damping controller, the design process takes into account a wide range of operating conditions and system configurations. The simulation results prove the effectiveness and robustness of the proposed method in terms of a high performance power system. The simulation study shows that the designed controller by Iteration PSO performs better than Classical PSO in finding the solution.
Abstract: The protection of parallel transmission lines has been a challenging task due to mutual coupling between the adjacent circuits of the line. This paper presents a novel scheme for detection and classification of faults on parallel transmission lines. The proposed approach uses combination of wavelet transform and neural network, to solve the problem. While wavelet transform is a powerful mathematical tool which can be employed as a fast and very effective means of analyzing power system transient signals, artificial neural network has a ability to classify non-linear relationship between measured signals by identifying different patterns of the associated signals. The proposed algorithm consists of time-frequency analysis of fault generated transients using wavelet transform, followed by pattern recognition using artificial neural network to identify the type of the fault. MATLAB/Simulink is used to generate fault signals and verify the correctness of the algorithm. The adaptive discrimination scheme is tested by simulating different types of fault and varying fault resistance, fault location and fault inception time, on a given power system model. The simulation results show that the proposed scheme for fault diagnosis is able to classify all the faults on the parallel transmission line rapidly and correctly.
Abstract: Study on suppression of interference in time domain equalizers is attempted for high data rate impulse radio (IR) ultra wideband communication system. The narrow band systems may cause interference with UWB devices as it is having very low transmission power and the large bandwidth. SRAKE receiver improves system performance by equalizing signals from different paths. This enables the use of SRAKE receiver techniques in IRUWB systems. But Rake receiver alone fails to suppress narrowband interference (NBI). A hybrid SRake-MMSE time domain equalizer is proposed to overcome this by taking into account both the effect of the number of rake fingers and equalizer taps. It also combats intersymbol interference. A semi analytical approach and Monte-Carlo simulation are used to investigate the BER performance of SRAKEMMSE receiver on IEEE 802.15.3a UWB channel models. Study on non-line of sight indoor channel models (both CM3 and CM4) illustrates that bit error rate performance of SRake-MMSE receiver with NBI performs better than that of Rake receiver without NBI. We show that for a MMSE equalizer operating at high SNR-s the number of equalizer taps plays a more significant role in suppressing interference.
Abstract: This paper presents a new version of the SVM mixture algorithm initially proposed by Kwok for classification and regression problems. For both cases, a slight modification of the mixture model leads to a standard SVM training problem, to the existence of an exact solution and allows the direct use of well known decomposition and working set selection algorithms. Only the regression case is considered in this paper but classification has been addressed in a very similar way. This method has been successfully applied to engine pollutants emission modeling.