Abstract: The fluid-structure coupling is a natural phenomenon which reflects the effects of two continuums: fluid and structure of different types in the reciprocal action on each other, involving knowledge of elasticity and fluid mechanics. The solution for such problems is based on the relations of continuum mechanics and is mostly solved with numerical methods. It is a computational challenge to solve such problems because of the complex geometries, intricate physics of fluids, and complicated fluid-structure interactions. The way in which the interaction between fluid and solid is described gives the largest opportunity for reducing the computational effort. In this paper, a problem of fluid structure interaction is investigated with two-way coupling method. The formulation Arbitrary Lagrangian-Eulerian (ALE) was used, by considering a dynamic grid, where the solid is described by a Lagrangian formulation and the fluid by a Eulerian formulation. The simulation was made on the ANSYS software.
Abstract: Mineral mapping on the Moon surface provides the clue to understand the origin, evolution, stratigraphy and geological history of the Moon. Recently, reflectance imaging spectroscopy plays a significant role in identifying minerals on the planetary surface in the Visible to NIR region of the electromagnetic spectrum. The Moon Mineralogy Mapper (M3) onboard Chandrayaan-1 provides unprecedented spectral data of lunar surface to study about the Moon surface. Here we used the M3 sensor data (hyperspectral imaging spectroscopy) for analysing mineralogy of Orientale basin region on the Moon surface. Reflectance spectrums were sampled from different locations of the basin and continuum was removed using ENvironment for Visualizing Images (ENVI) software. Reflectance spectra of unknown mineral composition were compared with known Reflectance Experiment Laboratory (RELAB) spectra for discriminating mineralogy. Minerals like olivine, Low-Ca Pyroxene (LCP), High-Ca Pyroxene (HCP) and plagioclase were identified. In addition to these minerals, an unusual type of spectral signature was identified, which indicates the probable Fe-Mg-spinel lithology in the basin region.
Abstract: Asphalt pavement itself is a mixture made up of mainly aggregates, binders, and fillers that acts as a composition used for pavement construction. An experimental program was setup to determine the fatigue performance test of Asphalt with three different grades of conventional binders. Asphalt specimen has achieved the maximum optimum bulk density and air voids with a consistent bulk density of 2.3 t/m3, with an air void of 5% ± 0.5, before loading into the Asphalt Mixture Performance Tested (AMPT) for fatigue test. The number of cycles is defined as the point where phase angle drops, which is caused by the formation of cracks due to the increasing micro cracks when asphalt is undergoing repeated cycles of loading. Thus, the data collected are analyzed using the drop of phase angle as failure criteria. Based in the data analyzed, it is evident that the fatigue life of asphalt lies on the grade of binder. The result obtained shows that all specimens do experience a drop in phase angle due to macro cracks in the asphalt specimen.
Abstract: In this article, we used the residual correction method
to deal with transient thermoelastic problems with a hollow spherical
region when the continuum medium possesses spherically isotropic
thermoelastic properties. Based on linear thermoelastic theory, the
equations of hyperbolic heat conduction and thermoelastic motion
were combined to establish the thermoelastic dynamic model with
consideration of the deformation acceleration effect and non-Fourier
effect under the condition of transient thermal shock. The approximate
solutions of temperature and displacement distributions are obtained
using the residual correction method based on the maximum principle
in combination with the finite difference method, making it easier and
faster to obtain upper and lower approximations of exact solutions.
The proposed method is found to be an effective numerical method
with satisfactory accuracy. Moreover, the result shows that the effect
of transient thermal shock induced by deformation acceleration is
enhanced by non-Fourier heat conduction with increased peak stress.
The influence on the stress increases with the thermal relaxation time.
Abstract: The purpose of the study is to find out relation of
moral massage between the authority and globalization in proverb.
Proverb is one of the many forms of cultural identity of the
Indonesian/Malay people filled with moral values. The values
contained within those proverbs are beneficial not only to the society,
but also to those who held power amidst on this era of globalization.
The method being used is qualitative research through content
analysis which is done by describing and uncovering the forms and
meanings of proverbs used within Indonesia Minangkabau society.
Sources for this study’s data were extracted from a Minangkabau
native speaker in the sub district of Tanah Abang, Jakarta. Said
sources were retrieved through a series of interviews with the
Minangkabau native speaker, whose speech is still adorned with
idiomatic expressions. The research findings show that there are 30
existed proverbs or idiomatic expressions in the Minangkabau
language often used by its indigenous people. The thirty data contain
moral values which are closely interwoven with the matter of power
and globalization. Analytical results show that the fourteen moral
values contained within proverbs reflect a firm connection between
rule and power in globalization; such as: responsible, brave,
togetherness and consensus, tolerance, politeness, thorough and
meticulous, honest and keeping promise, ingenious and learning,
care, self-correction, be fair, alert, arbitrary, self-awareness.
Structurally, proverbs possess an unchangeably formal construction;
symbolically, proverbs possess meanings that are clearly decided
through ethnographic communicative factors along with situational
and cultural contexts. Values contained within proverbs may be used
as a guide in social management, be it between fellow men, between
men and nature, or even between men and their Creator. Therefore,
the meanings and values contained within the morals of proverbs
could also be utilized as a counsel for those who rule and in charge of
power in order to stem the tides of globalization that had already
spread into sectoral, territorial and educational continuums.
Abstract: The quantitative study of cell mechanics is of
paramount interest, since it regulates the behaviour of the living cells
in response to the myriad of extracellular and intracellular
mechanical stimuli. The novel experimental techniques together with
robust computational approaches have given rise to new theories and
models, which describe cell mechanics as combination of
biomechanical and biochemical processes. This review paper
encapsulates the existing continuum-based computational approaches
that have been developed for interpreting the mechanical responses of
living cells under different loading and boundary conditions. The
salient features and drawbacks of each model are discussed from both
structural and biological points of view. This discussion can
contribute to the development of even more precise and realistic
computational models of cell mechanics based on continuum
approaches or on their combination with microstructural approaches,
which in turn may provide a better understanding of
mechanotransduction in living cells.
Abstract: In this study free vibration analysis of aluminum
honeycomb sandwich structures were carried out experimentally and
numerically. The natural frequencies and mode shapes of sandwich
structures fabricated with different configurations for clamped-free
boundary condition were determined. The effects of lower and upper
face sheet thickness, the core material thickness, cell diameter, cell
angle and foil thickness on the vibration characteristics were
examined. The numerical studies were performed with ANSYS
package. While the sandwich structures were modeled in ANSYS the
continuum model was used. Later, the numerical results were
compared with the experimental findings.
Abstract: The concentrations of heavy metals in sediments of
Qua Iboe River Estuary (QIRE) were monitored at four different
sampling locations in wet and dry seasons. A preliminary survey to
determine the four sampling stations along the river continuum
showed that the area spanned between
Abstract: Previous studies on financial distress prediction choose
the conventional failing and non-failing dichotomy; however, the
distressed extent differs substantially among different financial
distress events. To solve the problem, “non-distressed”, “slightlydistressed”
and “reorganization and bankruptcy” are used in our article
to approximate the continuum of corporate financial health. This paper
explains different financial distress events using the two-stage method.
First, this investigation adopts firm-specific financial ratios, corporate
governance and market factors to measure the probability of various
financial distress events based on multinomial logit models.
Specifically, the bootstrapping simulation is performed to examine the
difference of estimated misclassifying cost (EMC). Second, this work
further applies macroeconomic factors to establish the credit cycle
index and determines the distressed cut-off indicator of the two-stage
models using such index. Two different models, one-stage and
two-stage prediction models are developed to forecast financial
distress, and the results acquired from different models are compared
with each other, and with the collected data. The findings show that the
one-stage model has the lower misclassification error rate than the
two-stage model. The one-stage model is more accurate than the
two-stage model.
Abstract: Starting from nonlocal continuum mechanics, a
thermodynamically new nonlocal model of Euler-Bernoulli
nanobeams is provided. The nonlocal variational formulation is
consistently provided and the governing differential equation for
transverse displacement is presented. Higher-order boundary
conditions are then consistently derived. An example is contributed in
order to show the effectiveness of the proposed model.
Abstract: Enterprise Architecture (EA) Implementation
Methodologies have become an important part of EA projects.
Several implementation methodologies have been proposed, as a
theoretical and practical approach, to facilitate and support the
development of EA within an enterprise. A significant question when
facing the starting of EA implementation is deciding which
methodology to utilize. In order to answer this question, a framework
with several criteria is applied in this paper for the comparative
analysis of existing EA implementation methodologies. Five EA
implementation methodologies including: EAP, TOGAF, DODAF,
Gartner, and FEA are selected in order to compare with proposed
framework. The results of the comparison indicate that those
methodologies have not reached a sufficient maturity as whole due to
lack of consideration on requirement management, maintenance,
continuum, and complexities in their process. The framework has
also ability for the evaluation of any kind of EA implementation
methodologies.
Abstract: The numerical simulation of fully developed gas–solid flow in a horizontal pipe is done using the eulerian-eulerian approach, also known as two fluids modeling as both phases are treated as continuum and inter-penetrating continua. The solid phase stresses are modeled using kinetic theory of granular flow (KTGF). The computed results for velocity profiles and pressure drop are compared with the experimental data. We observe that the convection and diffusion terms in the granular temperature cannot be neglected in gas solid flow simulation along a horizontal pipe. The particle-wall collision and lift also play important role in eulerian modeling. We also investigated the effect of flow parameters like gas velocity, particle properties and particle loading on pressure drop prediction in different pipe diameters. Pressure drop increases with gas velocity and particle loading. The gas velocity has the same effect ((proportional toU2 ) as single phase flow on pressure drop prediction. With respect to particle diameter, pressure drop first increases, reaches a peak and then decreases. The peak is a strong function of pipe bore.
Abstract: In the present paper the extreme shear stresses with the corresponding planes are established using the freely available computer tools like the Gnuplot, Sage, R, Python and Octave. In order to support these freely available computer tools, their strong symbolical and graphical abilities are illustrated. The nature of the stationary points obtained by the Method of Lagrangian Multipliers can be determined using freely available computer symbolical tools like Sage. The characters of the stationary points can be explained in the easiest way using freely available computer graphical tools like Gnuplot, Sage, R, Python and Octave. The presented figures improve the understanding of the problem and the obtained solutions for the majority of students of civil or mechanical engineering.
Abstract: This paper presents the prediction of air flow,
humidity and temperature patterns in a co-current pilot plant spray
dryer fitted with a pressure nozzle using a three dimensional model.
The modelling was done with a Computational Fluid Dynamic
package (Fluent 6.3), in which the gas phase is modelled as
continuum using the Euler approach and the droplet/ particle phase is
modelled by the Discrete Phase model (Lagrange approach).Good
agreement was obtained with published experimental data where the
CFD simulation correctly predicts a fast downward central flowing
core and slow recirculation zones near the walls. In this work, the
effects of the air flow pattern on droplets trajectories, residence time
distribution of droplets and deposition of the droplets on the wall also
were investigated where atomizing of maltodextrin solution was
used.
Abstract: In this paper, we summarize recent work of the authors on nanocomputing memory devices. We investigate two memory devices, each comprising a charged metallofullerene and carbon nanotubes. The first device involves two open nanotubes of the same radius that are joined by a centrally located nanotube of a smaller radius. A metallofullerene is then enclosed inside the structure. The second device also involves a etallofullerene that is located inside a closed carbon nanotube. Assuming the Lennard-Jones interaction energy and the continuum approximation, for both devices, the metallofullerene has two symmetrically placed equal minimum energy positions. On one side the metallofullerene represents the zero information state and by applying an external electrical field, it can overcome the energy barrier, and pass from one end of the tube to the other, where the metallofullerene then represents the one information state.
Abstract: A continuum model is presented to study vdW
interaction on buckling analysis of multi-walled walled carbon
nanotube. In previous studies, only the vdW interaction between
adjacent two layers was considered and the vdW interaction between
the other two layers was neglected. The results show that the vdW
interaction cofficients are dependent on the change of interlayer
spacing and the radii of tubes. With increase of radii the vdW
coefficients approach a constant value. The numerical results show
that the effect of vdW interaction on the critical strain for a doublewalled
CNT is negligible when the radius is large enough for the
both the cases of before and after buckling.
Abstract: In the present article, nonlinear vibration analysis of
single layer graphene sheets is presented and the effect of small
length scale is investigated. Using the Hamilton's principle, the three
coupled nonlinear equations of motion are obtained based on the von
Karman geometrical model and Eringen theory of nonlocal
continuum. The solutions of Free nonlinear vibration, based on a one
term mode shape, are found for both simply supported and clamped
graphene sheets. A complete analysis of graphene sheets with
movable as well as immovable in-plane conditions is also carried out.
The results obtained herein are compared with those available in the
literature for classical isotropic rectangular plates and excellent
agreement is seen. Also, the nonlinear effects are presented as
functions of geometric properties and small scale parameter.
Abstract: This paper applies the homotopy analysis method method to a nonlinear differential-difference equation arising in nanotechnology. Continuum hypothesis on nanoscales is invalid, and a differential-difference model is considered as an alternative approach to describing discontinued problems. Comparison of the approximate solution with the exact one reveals that the method is very effective.
Abstract: The predictability of masonry arch bridges and their
behaviour is widely considered doubtful due to the lack of knowledge
about the conditions of a given masonry arch bridge. The assessment
methods for masonry arch bridges are MEXE, ARCHIE, RING and
Frame Analysis Method. The material properties of the masonry and
fill material are extremely difficult to determine accurately.
Consequently, it is necessary to examine the effect of load dispersal
angle through the fill material, the effect of variations in the stiffness
of the masonry, the tensile strength of the masonry mortar continuum
and the compressive strength of the masonry mortar continuum. It is
also important to understand the effect of fill material on load
dispersal angle to determine their influence on ratings. In this paper a
series of parametric studies, to examine the sensitivity of assessment
ratings to the various sets of input data required by the frame analysis
method, are carried out.
Abstract: An inflation–extension test with human vena cava
inferior was performed with the aim to fit a material model. The vein
was modeled as a thick–walled tube loaded by internal pressure and
axial force. The material was assumed to be an incompressible
hyperelastic fiber reinforced continuum. Fibers are supposed to be
arranged in two families of anti–symmetric helices. Considered
anisotropy corresponds to local orthotropy. Used strain energy
density function was based on a concept of limiting strain
extensibility. The pressurization was comprised by four pre–cycles
under physiological venous loading (0 – 4kPa) and four cycles under
nonphysiological loading (0 – 21kPa). Each overloading cycle was
performed with different value of axial weight. Overloading data
were used in regression analysis to fit material model. Considered
model did not fit experimental data so good. Especially predictions
of axial force failed. It was hypothesized that due to
nonphysiological values of loading pressure and different values of
axial weight the material was not preconditioned enough and some
damage occurred inside the wall. A limiting fiber extensibility
parameter Jm was assumed to be in relation to supposed damage.
Each of overloading cycles was fitted separately with different values
of Jm. Other parameters were held the same. This approach turned out
to be successful. Variable value of Jm can describe changes in the
axial force – axial stretch response and satisfy pressure – radius
dependence simultaneously.