Abstract: Over the course of the past century, the global
automotive industry-s stance towards safety has evolved from one of
contempt to one nearing reverence. A suspension system that
provides safe handling and cornering capabilities can, with the help
of an efficient braking system, improve safety to a large extent. The
aim of this research is to propose a new automotive brake rotor
design and to compare it with automotive vented disk rotor. Static
structural and transient thermal analysis have been carried out on the
vented disk rotor and proposed rotor designs to evaluate and compare
their performance. Finite element analysis was employed for both
static structural and transient thermal analysis. Structural analysis
was carried out to study the stress and deformation pattern of the
rotors under extreme loads. Time varying temperature load was
applied on the rotors and the temperature distribution was analysed
considering cooling parameters (convection and radiation). This
dissertation illustrates the use of Finite Element Methods to examine
models, concluding with a comparative study of the proposed rotor
design and the conventional vented disk rotor for structural stability
and thermal efficiency.
Abstract: An attempt has been made to beneficiate the Indian
coking coal fines by a combination of Spiral, flotation and Oleo
Flotation processes. Beneficiation studies were also carried out on -
0.5mm coal fines using flotation and oleo flotation by splitting at size
0.063mm.Size fraction of 0.5mm-0.063mm and -0.063mm size were
treated in flotation and Oleo flotation respectively. The washability
studies on the fraction 3-0.5 mm indicated that good separation may
be achieved when it is fed in a spiral. Combined product of Spiral,
Flotation and Oleo Flotation has given a significant yield at
acceptable ash%. Studies were also conducted to see the dewatering
of combined product by batch type centrifuge. It may further be
suggested that combination of different processes may be used to
treat the -3 mm fraction in an integrated manner to achieve the yield
at the desired ash level. The treatment of the 3/1 mm -0.5 mm size
fraction by spiral,-0.5-0.63 mm by conventional froth flotation and -
0.063 fractions by oleo flotation may provide a complete solution of
beneficiation and dewatering of coal fines, and can effectively
address the environmental problems caused by coal fines.
Abstract: It is well known that enhancing interfacial adhesion
between inorganic filler and matrix resin in a composite lead to
favorable properties such as excellent mechanical properties, high
thermal resistance, prominent electric insulation, low expansion
coefficient, and so on. But it should be avoided that much excess of
coupling agent is reacted due to a negative impact of their final
composite-s properties. There is no report to achieve classification of
the bonding state excepting investigation of coating layer thickness.
Therefore, the analysis of the bonding state of the coupling agent
reacted with the filler surface such as BN particles with less functional
group and silica particles having much functional group was
performed by thermal gravimetric analysis and pyrolysis GC/MS. The
reacted number of functional groups on the silane-coupling agent was
classified as a result of the analysis. Thus, we succeeded in classifying
the reacted number of the functional groups as a result of this study.
Abstract: Aim. We have introduced the notion of order to multinormed spaces and countable union spaces and their duals. The topology of bounded convergence is assigned to the dual spaces. The aim of this paper is to develop the theory of ordered topological linear
spaces La,b, L(w, z), the dual spaces of ordered multinormed spaces
La,b, ordered countable union spaces L(w, z), with the topology of bounded convergence assigned to the dual spaces. We apply Laplace transformation to the ordered linear space of Laplace transformable
generalized functions. We ultimately aim at finding solutions to nonhomogeneous
nth order linear differential equations with constant
coefficients in terms of generalized functions and comparing different
solutions evolved out of different initial conditions.
Method. The above aim is achieved by
• Defining the spaces La,b, L(w, z).
• Assigning an order relation on these spaces by identifying a
positive cone on them and studying the properties of the cone.
• Defining an order relation on the dual spaces La,b, L(w, z) of La,b, L(w, z) and assigning a topology to these dual spaces which makes the order dual and the topological dual the same. • Defining the adjoint of a continuous map on these spaces
and studying its behaviour when the topology of bounded
convergence is assigned to the dual spaces.
• Applying the two-sided Laplace Transformation on the ordered
linear space of generalized functions W and studying some
properties of the transformation which are used in solving
differential equations.
Result. The above techniques are applied to solve non-homogeneous
n-th order linear differential equations with constant coefficients in
terms of generalized functions and to compare different solutions of the differential equation.
Abstract: The purpose of this paper is to present a Dynamic
Time Warping technique which reduces significantly the data
processing time and memory size of multi-dimensional time series
sampled by the biometric smart pen device BiSP. The acquisition
device is a novel ballpoint pen equipped with a diversity of sensors
for monitoring the kinematics and dynamics of handwriting
movement. The DTW algorithm has been applied for time series
analysis of five different sensor channels providing pressure,
acceleration and tilt data of the pen generated during handwriting on
a paper pad. But the standard DTW has processing time and memory
space problems which limit its practical use for online handwriting
recognition. To face with this problem the DTW has been applied to
the sum of the five sensor signals after an adequate down-sampling
of the data. Preliminary results have shown that processing time and
memory size could significantly be reduced without deterioration of
performance in single character and word recognition. Further
excellent accuracy in recognition was achieved which is mainly due
to the reduced dynamic time warping RDTW technique and a novel
pen device BiSP.
Abstract: This paper deals with econometric analysis of real
retail trade turnover. It is a part of an extensive scientific research
about modern trends in Croatian national economy. At the end of the
period of transition economy, Croatia confronts with challenges and
problems of high consumption society. In such environment as
crucial economic variables: real retail trade turnover, average
monthly real wages and household loans are chosen for consequence
analysis. For the purpose of complete procedure of multiple
econometric analysis data base adjustment has been provided.
Namely, it has been necessary to deflate original national statistics
data of retail trade turnover using consumer price indices, as well as
provide process of seasonally adjustment of its contemporary
behavior. In model establishment it has been necessary to involve the
overcoming procedure for the autocorrelation and colinearity
problems. Moreover, for case of time-series shift a specific
appropriate econometric instrument has been applied. It would be
emphasize that the whole methodology procedure is based on the real
Croatian national economy time-series.
Abstract: This paper presents the use of the predictive fuzzy logic controller (PFLC) applied to attitude control system for agile micro-satellite. In order to reduce the effect of unpredictable time delays and large uncertainties, the algorithm employs predictive control to predict the attitude of the satellite. Comparison of the PFLC and conventional fuzzy logic controller (FLC) is presented to evaluate the performance of the control system during attitude maneuver. The two proposed models have been analyzed with the same level of noise and external disturbances. Simulation results demonstrated the feasibility and advantages of the PFLC on the attitude determination and control system (ADCS) of agile satellite.
Abstract: In this paper presents the mathematical model of
hydrothermal processes in thermal power plant with different wind
direction scenarios in the water reservoir, which is solved by the
Navier - Stokes and temperature equations for an incompressible
fluid in a stratified medium. Numerical algorithm based on the
method of splitting by physical parameters. Three dimensional
Poisson equation is solved with Fourier method by combination of
tridiagonal matrix method (Thomas algorithm).
Abstract: The forced convection heat transfer in high porosity metal-foam filled tube heat exchangers are studied in this paper. The Brinkman Darcy momentum model and two energy equations for both solid and fluid phases in porous media are employed .The study shows that using metal-foams can significantly improve the heat transfer in heat exchangers.
Abstract: The flexible follower response of a translating cam with
four different profiles for rise-dwell-fall-dwell (RDFD) motion is
investigated. The cycloidal displacement motion, the modified
sinusoidal acceleration motion, the modified trapezoidal acceleration
motion, and the 3-4-5 polynomial motion are employed to describe the
rise and the fall motions of the follower and the associated four kinds of
cam profiles are studied. Since the follower flexibility is considered,
the contact point of the roller and the cam is an unknown. Two
geometric constraints formulated to restrain the unknown position are
substituted into Hamilton-s principle with Lagrange multipliers.
Applying the assumed mode method, one can obtain the governing
equations of motion as non-linear differential-algebraic equations. The
equations are solved using Runge-Kutta method. Then, the responses of
the flexible follower undergoing the four different motions are
investigated in time domain and in frequency domain.
Abstract: The evaluation of energy release rate and centre Crack
Opening Displacement (COD) for circumferential Through-Wall
Cracked (TWC) pipes is an important issue in the assessment of
critical crack length for unstable fracture. The ability to predict crack
growth continues to be an important component of research for
several structural materials. Crack growth predictions can aid the
understanding of the useful life of a structural component and the
determination of inspection intervals and criteria. In this context,
studies were carried out at CSIR-SERC on Nuclear Power Plant
(NPP) piping components subjected to monotonic as well as cyclic
loading to assess the damage for crack growth due to low-cycle
fatigue in circumferentially TWC pipes.
Abstract: Having done in this study, air-conditioning
automation for patisserie shopwindow was designed. In the cooling
sector it is quite important to cooling up the air temperature in the
shopwindow within short time interval. Otherwise the patisseries
inside of the shopwindow will be spoilt in a few days. Additionally
the humidity is other important parameter for the patisseries kept in
shopwindow. It must be raised up to desired level in a quite short
time. Traditional patisserie shopwindows only allow controlling
temperature manually. There is no humidity control and humidity is
supplied by fans that are directed to the water at the bottom of the
shopwindows. In this study, humidity and temperature sensors
(SHT11), PIC, AC motor controller, DC motor controller, ultrasonic
nebulizer and other electronic circuit members were used to simulate
air conditioning automation for patisserie shopwindow in proteus
software package. The simulation results showed that temperature
and humidity values are adjusted in desired time duration by openloop
control technique. Outer and inner temperature and humidity
values were used for control mechanism.
Abstract: This paper derives some new sufficient conditions for
the stability of a class of neutral-type neural networks with discrete
time delays by employing a suitable Lyapunov functional. The
obtained conditions can be easily verified as they can be expressed
in terms of the network parameters only. It is shown that the results
presented in this paper for neutral-type delayed neural networks establish
a new set of stability criteria, and therefore can be considered
as the alternative results to the previously published literature results.
A numerical example is also given to demonstrate the applicability
of our proposed stability criterion.
Abstract: In this paper 2D Simulation of catalytic Fixed Bed Reactor in Fischer-Tropsch Synthesis of GTL technology has been performed utilizing computational fluid dynamics (CFD). Synthesis gas (a mixture of carbon monoxide and hydrogen) has been used as feedstock. The reactor was modeled and the model equations were solved employing finite volume method. The model was validated against the experimental data reported in literature. The comparison showed a good agreement between simulation results and the experimental data. In addition, the model was applied to predict the concentration contours of the reactants and products along the length of reactor.
Abstract: A vast array of biological materials, especially algae have received increasing attention for heavy metal removal. Algae have been proven to be cheaper, more effective for the removal of metallic elements in aqueous solutions. A fresh water algal strain was isolated from Zoo Lake, Johannesburg, South Africa and identified as Desmodesmus sp. This paper investigates the efficacy of Desmodesmus sp.in removing heavy metals contaminating the Wonderfonteinspruit Catchment Area (WCA) water bodies. The biosorption data fitted the pseudo-second order and Langmuir isotherm models. The Langmuir maximum uptakes gave the sequence: Mn2+>Ni2+>Fe2+. The best results for kinetic study was obtained in concentration 120 ppm for Fe3+ and Mn2+, whilst for Ni2+ was at 20 ppm, which is about the same concentrations found in contaminated water in the WCA (Fe3+115 ppm, Mn2+ 121 ppm and Ni2+ 26.5 ppm).
Abstract: Now-a-days, numbers of simulation software are
being used all over the world to solve Computational Fluid
Dynamics (CFD) related problems. In this present study, a
commercial CFD simulation software namely STAR-CCM+ is
applied to analyze the airflow characteristics inside a 2.5" hard
disk drive. Each step of the software is described adequately to
obtain the output and the data are verified with the theories to
justify the robustness of the simulation outcome. This study
gives an insight about the accuracy level of the CFD
simulation software to compute CFD related problems
although it largely depends upon the computer speed. Also
this study will open avenues for further research.
Abstract: The research study was based on an evaluation of the
ability of glued test samples to pass the criterion of sufficient
bondline adhesion under the exposure conditions defined in EN 302-
1. Additionally, an infrared spectroscopic analysis of the evaluated
adhesives (phenol-resorcinol-formaldehyde PRF and melamine-ureaformaldehyde
MUF) with different mix ratios was carried out to
evaluate the possible effects of a faulty technological process.
Abstract: The effect of chemical treatment in CdCl2 on the
compositional changes and defect structures of potentially useful ZnS
solar cell thin films prepared by vacuum deposition method was
studied using the complementary Rutherford backscattering (RBS)
and Thermoluminesence (TL) techniques. A series of electron and
hole traps are found in the various as deposited samples studied.
After treatment, perturbation on the intensity is noted; mobile defect
states and charge conversion and/or transfer between defect states are
found.
Abstract: In many applications, magnetic suspension systems
are required to operate over large variations in air gap. As a result,
the nonlinearities inherent in most types of suspensions have a
significant impact on performance. Specifically, it may be difficult to
design a linear controller which gives satisfactory performance,
stability, and disturbance rejection over a wide range of operating
points. in this paper an optimal controller based on discontinuous
mathematical model of the system for an electromagnetic suspension
system which is applied in magnetic trains has been designed .
Simulations show that the new controller can adapt well to the
variance of suspension mass and gap, and keep its dynamic
performance, thus it is superior to the classic controller.
Abstract: The human knee joint has a three dimensional
geometry with multiple body articulations that produce complex
mechanical responses under loads that occur in everyday life and
sports activities. To produce the necessary joint compliance and
stability for optimal daily function various menisci and ligaments are
present while muscle forces are used to this effect. Therefore,
knowledge of the complex mechanical interactions of these load
bearing structures is necessary when treatment of relevant diseases is
evaluated and assisting devices are designed.
Numerical tools such as finite element analysis are suitable for
modeling such joints in order to understand their physics. They have
been used in the current study to develop an accurate human knee
joint and model its mechanical behavior. To evaluate the efficacy of
this articulated model, static load cases were used for comparison
purposes with previous experimentally verified modeling works
drawn from literature.