Abstract: We have studied the migration of a charged permeable aggregate in electrolyte under the influence of an axial electric field and pressure gradient. The migration of the positively charged aggregate leads to a deformation of the anionic cloud around it. The hydrodynamics of the aggregate is governed by the interaction of electroosmotic flow in and around the particle, hydrodynamic friction and electric force experienced by the aggregate. We have computed the non-linear Nernest-Planck equations coupled with the Dracy- Brinkman extended Navier-Stokes equations and Poisson equation for electric field through a finite volume method. The permeability of the aggregate enable the counterion penetration. The penetration of counterions depends on the volume charge density of the aggregate and ionic concentration of electrolytes at a fixed field strength. The retardation effect due to the double layer polarization increases the drag force compared to an uncharged aggregate. Increase in migration sped from the electrophretic velocity of the aggregate produces further asymmetry in charge cloud and reduces the electric body force exerted on the particle. The permeability of the particle have relatively little influence on the electric body force when Double layer is relatively thin. The impact of the key parameters of electrokinetics on the hydrodynamics of the aggregate is analyzed.
Abstract: Simulation accuracy by recent dynamic vehicle
simulation multidimensional expression significantly has progressed
and acceptable results not only for passive vehicles but also for
active vehicles normally equipped with advanced electronic
components is also provided. Recently, one of the subjects that has it
been considered, is increasing the safety car in design. Therefore,
many efforts have been done to increase vehicle stability especially
in the turn. One of the most important efforts is adjusting the camber
angle in the car suspension system. Optimum control camber angle in
addition to the vehicle stability is effective in the wheel adhesion on
road, reducing rubber abrasion and acceleration and braking. Since
the increase or decrease in the camber angle impacts on the stability
of vehicles, in this paper, a car suspension system mechanism is
introduced that could be adjust camber angle and the mechanism is
application and also inexpensive. In order to reach this purpose, in
this paper, a passive double wishbone suspension system with
variable camber angle is introduced and then variable camber
mechanism designed and analyzed for study the designed system
performance, this mechanism is modeled in Visual Nastran software
and kinematic analysis is revealed.
Abstract: In this paper, a nonlinear acoustic echo cancellation
(AEC) system is proposed, whereby 3rd order Volterra filtering is
utilized along with a variable step-size Gauss-Seidel pseudo affine
projection (VSSGS-PAP) algorithm. In particular, the proposed
nonlinear AEC system is developed by considering a double-talk
situation with near-end signal variation. Simulation results
demonstrate that the proposed approach yields better nonlinear AEC
performance than conventional approaches.
Abstract: The performance of Advection Upstream Splitting
Method AUSM schemes are evaluated against experimental flow
fields at different Mach numbers and results are compared with
experimental data of subsonic, supersonic and hypersonic flow fields.
The turbulent model used here is SST model by Menter. The
numerical predictions include lift coefficient, drag coefficient and
pitching moment coefficient at different mach numbers and angle of
attacks. This work describes a computational study undertaken to
compute the Aerodynamic characteristics of different air vehicles
configurations using a structured Navier-Stokes computational
technique. The CFD code bases on the idea of upwind scheme for the
convective (convective-moving) fluxes. CFD results for GLC305
airfoil and cone cylinder tail fined missile calculated on above
mentioned turbulence model are compared with the available data.
Wide ranges of Mach number from subsonic to hypersonic speeds are
simulated and results are compared. When the computation is done
by using viscous turbulence model the above mentioned coefficients
have a very good agreement with the experimental values. AUSM
scheme is very efficient in the regions of very high pressure gradients
like shock waves and discontinuities. The AUSM versions simulate
the all types of flows from lower subsonic to hypersonic flow without
oscillations.
Abstract: Ambient Intelligence (AmI) environments bring
significant potential to exploit sophisticated computer technology in
everyday life. In particular, the educational domain could be
significantly enhanced through AmI, as personalized and adapted
learning could be transformed from paper concepts and prototypes to
real-life scenarios. In this paper, an integrated framework is
presented, named ClassMATE, supporting ubiquitous computing and
communication in a school classroom. The main objective of
ClassMATE is to enable pervasive interaction and context aware
education in the technologically augmented classroom of the future.
Abstract: This paper presents the modeling and simulation of a hybrid proton exchange membrane fuel cell (PEMFC) with an energy storage system for use in a stand-alone distributed generation (DG) system. The simulation model consists of fuel cell DG, lead-acid battery, maximum power point tracking and power conditioning unit which is modeled in the MATLAB/Simulink platform. Poor loadfollowing characteristics and slow response to rapid load changes are some of the weaknesses of PEMFC because of the gas processing reaction and the fuel cell dynamics. To address the load-tracking issues in PEMFC, a hybrid PEMFC and battery storage system is considered and modelled. The model utilizes PEMFC as the main energy source whereas the battery functions as energy storage to compensate for the limitations of PEMFC.Simulation results are given to show the overall system performance under light and heavyloading conditions.
Abstract: Bubble columns have a variety of applications in
absorption, bio-reactions, catalytic slurry reactions, and coal
liquefaction; because they are simple to operate, provide good heat
and mass transfer, having less operational cost. The use of
Computational Fluid Dynamics (CFD) for bubble column becomes
important, since it can describe the fluid hydrodynamics on both local
and global scale. Euler- Euler two-phase fluid model has been used to
simulate two-phase (air and water) transient up-flow in bubble
column (15cm diameter) using FLUENT6.3. These simulations and
experiments were operated over a range of superficial gas velocities
in the bubbly flow and churn turbulent regime (1 to16 cm/s) at
ambient conditions. Liquid velocity was varied from 0 to 16cm/s. The
turbulence in the liquid phase is described using the standard k-ε
model. The interactions between the two phases are described
through drag coefficient formulations (Schiller Neumann). The
objectives are to validate CFD simulations with experimental data,
and to obtain grid-independent numerical solutions. Quantitatively
good agreements are obtained between experimental data for hold-up
and simulation values. Axial liquid velocity profiles and gas holdup
profiles were also obtained for the simulation.
Abstract: This paper describes about dynamic reconfiguration to
miniaturize arithmetic circuits in general-purpose processor. Dynamic
reconfiguration is a technique to realize required functions by
changing hardware construction during operation. The proposed
arithmetic circuit performs floating-point arithmetic which is
frequently used in science and technology. The data format is
floating-point based on IEEE754. The proposed circuit is designed
using VHDL, and verified the correct operation by simulations and
experiments.
Abstract: In this manuscript, we discuss the problem of determining the optimum stratification of a study (or main) variable based on the auxiliary variable that follows a uniform distribution. If the stratification of survey variable is made using the auxiliary variable it may lead to substantial gains in precision of the estimates. This problem is formulated as a Nonlinear Programming Problem (NLPP), which turn out to multistage decision problem and is solved using dynamic programming technique.
Abstract: This paper describes a newly designed decentralized
nonlinear control strategy to control a robot manipulator. Based on the
concept of the nonlinear state feedback theory and decentralized
concept is developed to improve the drawbacks in previous works
concerned with complicate intelligent control and low cost effective
sensor. The control methodology is derived in the sense of Lyapunov
theorem so that the stability of the control system is guaranteed. The
decentralized algorithm does not require other joint angle and velocity
information. Individual Joint controller is implemented using a digital
processor with nearly actuator to make it possible to achieve good
dynamics and modular. Computer simulation result has been
conducted to validate the effectiveness of the proposed control scheme
under the occurrence of possible uncertainties and different reference
trajectories. The merit of the proposed control system is indicated in
comparison with a classical control system.
Abstract: This paper presents a new methodology to select test
cases from regression test suites. The selection strategy is based on
analyzing the dynamic behavior of the applications that written in
any programming language. Methods based on dynamic analysis are
more safe and efficient. We design a technique that combine the code
based technique and model based technique, to allow comparing the
object oriented of an application that written in any programming
language. We have developed a prototype tool that detect changes
and select test cases from test suite.
Abstract: Many real-world data sets consist of a very high dimensional feature space. Most clustering techniques use the distance or similarity between objects as a measure to build clusters. But in high dimensional spaces, distances between points become relatively uniform. In such cases, density based approaches may give better results. Subspace Clustering algorithms automatically identify lower dimensional subspaces of the higher dimensional feature space in which clusters exist. In this paper, we propose a new clustering algorithm, ISC – Intelligent Subspace Clustering, which tries to overcome three major limitations of the existing state-of-art techniques. ISC determines the input parameter such as є – distance at various levels of Subspace Clustering which helps in finding meaningful clusters. The uniform parameters approach is not suitable for different kind of databases. ISC implements dynamic and adaptive determination of Meaningful clustering parameters based on hierarchical filtering approach. Third and most important feature of ISC is the ability of incremental learning and dynamic inclusion and exclusions of subspaces which lead to better cluster formation.
Abstract: In this study, the hydrogen transport phenomenon was
numerically evaluated by using hydrogen-enhanced localized
plasticity (HELP) mechanisms. Two dominant governing equations,
namely, the hydrogen transport model and the elasto-plastic model,
were introduced. In addition, the implicitly formulated equations of
the governing equations were implemented into ABAQUS UMAT
user-defined subroutines. The simulation results were compared to
published results to validate the proposed method.
Abstract: Checkpointing is one of the commonly used techniques to provide fault-tolerance in distributed systems so that the system can operate even if one or more components have failed. However, mobile computing systems are constrained by low bandwidth, mobility, lack of stable storage, frequent disconnections and limited battery life. Hence, checkpointing protocols having lesser number of synchronization messages and fewer checkpoints are preferred in mobile environment. There are two different approaches, although not orthogonal, to checkpoint mobile computing systems namely, time-based and index-based. Our protocol is a fusion of these two approaches, though not first of its kind. In the present exposition, an index-based checkpointing protocol has been developed, which uses time to indirectly coordinate the creation of consistent global checkpoints for mobile computing systems. The proposed algorithm is non-blocking, adaptive, and does not use any control message. Compared to other contemporary checkpointing algorithms, it is computationally more efficient because it takes lesser number of checkpoints and does not need to compute dependency relationships. A brief account of important and relevant works in both the fields, time-based and index-based, has also been included in the presentation.
Abstract: This paper explores the changing trend in citizenship
norms among young citizens from various ethnic groups in Malaysia
and the extent to which it influences the participation of young
citizens in political and civil issues. Embedded in democratic
constitutions are the rights and freedoms that accompany citizenship,
and these rights and freedoms include participation. Participation in
democracies should go beyond voting; it should include taking part in
the governance process. The political process is not at risk even
though politics does not work as it did in the past. A national sample
of 1697 respondents between the ages of 21 and 40 years were
interviewed in January 2011. The findings show that respondents
embrace an engaged-citizenship norm more than they do the
traditional duty-citizen norm. Among the ethnic groups, the Chinese
show lower means in both citizenship norms compared with other
ethnic groups, namely, the Malays and the Indians. The duty-citizen
norm correlates higher with political participation than with civic
participation. On the other hand, the engaged-citizen norm correlates
higher with civic participation than with political participation.
Abstract: The dynamic speckle or biospeckle is an interference
phenomenon generated at the reflection of a coherent light by an
active surface or even by a particulate or living body surface. The
above mentioned phenomenon gave scientific support to a method
named biospeckle which has been employed to study seed viability,
biological activity, tissue senescence, tissue water content, fruit
bruising, etc. Since the above mentioned method is not invasive and
yields numerical values, it can be considered for possible automation
associated to several processes, including selection and sorting.
Based on these preliminary considerations, this research work
proposed to study the interaction of a laser beam with vegetative
samples by measuring the incident light intensity and the transmitted
light beam intensity at several vegetative slabs of varying thickness.
Tests were carried on fifteen slices of apple tissue divided into three
thickness groups, i.e., 4 mm, 5 mm, 18 mm and 22 mm. A diode laser
beam of 10mW and 632 nm wavelength and a Samsung digital
camera were employed to carry the tests. Outgoing images were
analyzed by comparing the gray gradient of a fixed image column of
each image to obtain a laser penetration scale into the tissue,
according to the slice thickness.
Abstract: This paper describes a simulation model for analyzing artificial emotion injected to design the game characters. Most of the game storyboard is interactive in nature and the virtual characters of the game are equipped with an individual personality and dynamic emotion value which is similar to real life emotion and behavior. The uncertainty in real expression, mood and behavior is also exhibited in game paradigm and this is focused in the present paper through a fuzzy logic based agent and storyboard. Subsequently, a pheromone distribution or labeling is presented mimicking the behavior of social insects.
Abstract: This paper presents Qmulus- a Cloud Based GPS
Model. Qmulus is designed to compute the best possible route which
would lead the driver to the specified destination in the shortest time
while taking into account real-time constraints. Intelligence
incorporated to Qmulus-s design makes it capable of generating and
assigning priorities to a list of optimal routes through customizable
dynamic updates. The goal of this design is to minimize travel and
cost overheads, maintain reliability and consistency, and implement
scalability and flexibility. The model proposed focuses on
reducing the bridge between a Client Application and a Cloud
service so as to render seamless operations. Qmulus-s system
model is closely integrated and its concept has the potential to be
extended into several other integrated applications making it capable
of adapting to different media and resources.
Abstract: The use of statistical data and of the neural networks, capable of elaborate a series of data and territorial info, have allowed the making of a model useful in the subdivision of urban places into homogeneous zone under the profile of a social, real estate, environmental and urbanist background of a city. The development of homogeneous zone has fiscal and urbanist advantages. The tools in the model proposed, able to be adapted to the dynamic changes of the city, allow the application of the zoning fast and dynamic.
Abstract: In this paper we present a full performance analysis of an energy conserving routing protocol in mobile ad hoc network, named ER-AODV (Energy Reverse Ad-hoc On-demand Distance Vector routing). ER-AODV is a reactive routing protocol based on a policy which combines two mechanisms used in the basic AODV protocol. AODV and most of the on demand ad hoc routing protocols use single route reply along reverse path. Rapid change of topology causes that the route reply could not arrive to the source node, i.e. after a source node sends several route request messages, the node obtains a reply message, and this increases in power consumption. To avoid these problems, we propose a mechanism which tries multiple route replies. The second mechanism proposes a new adaptive approach which seeks to incorporate the metric "residual energy " in the process route selection, Indeed the residual energy of mobile nodes were considered when making routing decisions. The results of simulation show that protocol ER-AODV answers a better energy conservation.