A Fault Tolerant Token-based Algorithm for Group Mutual Exclusion in Distributed Systems
The group mutual exclusion (GME) problem is a
variant of the mutual exclusion problem. In the present paper a
token-based group mutual exclusion algorithm, capable of handling
transient faults, is proposed. The algorithm uses the concept of
dynamic request sets. A time out mechanism is used to detect the
token loss; also, a distributed scheme is used to regenerate the token.
The worst case message complexity of the algorithm is n+1. The
maximum concurrency and forum switch complexity of the
algorithm are n and min (n, m) respectively, where n is the number of
processes and m is the number of groups. The algorithm also satisfies
another desirable property called smooth admission. The scheme can
also be adapted to handle the extended group mutual exclusion
Dynamic request sets, Fault tolerance, Smoothadmission, Transient faults.
A Distributed Group Mutual Exclusion Algorithm for Soft Real Time Systems
The group mutual exclusion (GME) problem is an
interesting generalization of the mutual exclusion problem. Several
solutions of the GME problem have been proposed for message
passing distributed systems. However, none of these solutions is
suitable for real time distributed systems. In this paper, we propose a
token-based distributed algorithms for the GME problem in soft real
time distributed systems. The algorithm uses the concepts of priority
queue, dynamic request set and the process state. The algorithm uses
first come first serve approach in selecting the next session type
between the same priority levels and satisfies the concurrent
occupancy property. The algorithm allows all n processors to be
inside their CS provided they request for the same session. The
performance analysis and correctness proof of the algorithm has also
been included in the paper.
Concurrency, Group mutual exclusion, Priority,Request set, Token.
High Impedance Fault Detection using LVQ Neural Networks
This paper presents a new method to detect high impedance faults in radial distribution systems. Magnitudes of third and fifth harmonic components of voltages and currents are used as a feature vector for fault discrimination. The proposed methodology uses a learning vector quantization (LVQ) neural network as a classifier for identifying high impedance arc-type faults. The network learns from the data obtained from simulation of a simple radial system under different fault and system conditions. Compared to a feed-forward neural network, a properly tuned LVQ network gives quicker response.
Fault identification, distribution networks, high
impedance arc-faults, feature vector, LVQ networks.
Accurate Fault Classification and Section Identification Scheme in TCSC Compensated Transmission Line using SVM
This paper presents a new approach for the protection
of Thyristor-Controlled Series Compensator (TCSC) line using
Support Vector Machine (SVM). One SVM is trained for fault
classification and another for section identification. This method use
three phase current measurement that results in better speed and
accuracy than other SVM based methods which used single phase
current measurement. This makes it suitable for real-time protection.
The method was tested on 10,000 data instances with a very wide
variation in system conditions such as compensation level, source
impedance, location of fault, fault inception angle, load angle at
source bus and fault resistance. The proposed method requires only
local current measurement.
Fault Classification, Section Identification, Feature
Selection, Support Vector Machine (SVM), Thyristor-Controlled
Series Compensator (TCSC)
Performance Evaluation of Intelligent Controllers for AGC in Thermal Systems
In an interconnected power system, any sudden small
load perturbation in any of the interconnected areas causes the
deviation of the area frequencies, the tie line power and voltage
deviation at the generator terminals. This paper deals with the study
of performance of intelligent Fuzzy Logic controllers coupled with
Conventional Controllers (PI and PID) for Load Frequency Control.
For analysis, an isolated single area and interconnected two area
thermal power systems with and without generation rate constraints
(GRC) have been considered. The studies have been performed with
conventional PI and PID controllers and their performance has been
compared with intelligent fuzzy controllers. It can be demonstrated
that these controllers can successfully bring back the excursions in
area frequencies and tie line powers within acceptable limits in
smaller time periods and with lesser transients as compared to the
performance of conventional controllers under same load disturbance
conditions. The simulations in MATLAB have been used for
Area Control Error, Fuzzy Logic, Generation rate
constraint, Load Frequency, Tie line Power.
Multi Response Optimization in Drilling Al6063/SiC/15% Metal Matrix Composite
This investigation proposes a grey-based Taguchi method to solve the multi-response problems. The grey-based Taguchi method is based on the Taguchi’s design of experimental method, and adopts grey relational analysis (GRA) to transfer multi-response problems into single-response problems. In this investigation, an attempt has been made to optimize the drilling process parameters considering weighted output response characteristics using grey relational analysis. The output response characteristics considered are surface roughness, burr height and hole diameter error under the experimental conditions of cutting speed, feed rate, step angle, and cutting environment. The drilling experiments were conducted using L27 orthogonal array. A combination of orthogonal array, design of experiments and grey relational analysis was used to ascertain best possible drilling process parameters that give minimum surface roughness, burr height and hole diameter error. The results reveal that combination of Taguchi design of experiment and grey relational analysis improves surface quality of drilled hole.
Metal matrix composite, Drilling, Optimization, step drill, Surface roughness, burr height, hole diameter error.
An Approach for the Integration of the Existing Wireless Networks
The demand of high quality services has fueled
dimensional research and development in wireless communications
and networking. As a result, different wireless technologies like
Wireless LAN, CDMA, GSM, UMTS, MANET, Bluetooth and
satellite networks etc. have emerged in the last two decades. Future
networks capable of carrying multimedia traffic need IP convergence,
portability, seamless roaming and scalability among the existing
networking technologies without changing the core part of the
existing communications networks. To fulfill these goals, the present
networking systems are required to work in cooperation to ensure
technological independence, seamless roaming, high security and
authentication, guaranteed Quality of Services (QoS). In this paper, a
conceptual framework for a cooperative network (CN) is proposed
for integration of heterogeneous existing networks to meet out the
requirements of the next generation wireless networks.
Cooperative Network, Wireless Network,
Segmentation of Noisy Digital Images with Stochastic Gradient Kernel
Image segmentation and edge detection is a fundamental section in image processing. In case of noisy images Edge Detection is very less effective if we use conventional Spatial Filters like Sobel, Prewitt, LOG, Laplacian etc. To overcome this problem we have proposed the use of Stochastic Gradient Mask instead of Spatial Filters for generating gradient images. The present study has shown that the resultant images obtained by applying Stochastic Gradient Masks appear to be much clearer and sharper as per Edge detection is considered.
Image segmentation, edge Detection, noisy images,
spatialfilters, stochastic gradient kernel.
Amino Acid Coated Silver Nanoparticles: A Green Catalyst for Methylene Blue Reduction
Highly stable and homogeneously dispersed amino
acid coated silver nanoparticles (ANP) of ≈ 10 nm diameter, ranging
from 420 to 430 nm are prepared on AgNO3 solution addition to gum
of Azadirachta indica solution at 373.15 K. The amino acids were
selected based on their polarity. The synthesized nanoparticles were
characterized by UV-Vis, FTIR spectroscopy, HR-TEM, XRD, SEM
and 1H-NMR. The coated nanoparticles were used as catalyst for the
reduction of methylene blue dye in presence of Sn(II) in aqueous,
anionic and cationic micellar media. The rate of reduction of dye was
determined by measuring the absorbance at 660 nm,
spectrophotometrically and followed the order: Kcationic > Kanionic >
Kwater. After 12 min and in absence of the ANP, only 2%, 3% and 6%
of the dye reduction was completed in aqueous, anionic and cationic
micellar media respectively while, in presence of ANP coated by
polar neutral amino acid with non-polar -R group, the reduction
completed to 84%, 95% and 98% respectively. The ANP coated with
polar neutral amino acid having non-polar -R group, increased the
rate of reduction of the dye by 94, 3205 and 6370 folds in aqueous,
anionic and cationic micellar media respectively. Also, the rate of
reduction of the dye increased by three folds when the micellar media
was changed from anionic to cationic when the ANP is coated by a
polar neutral amino acid having a non-polar -R group.
Silver nanoparticle, surfactant, methylene blue,
Effect of Collector Aspect Ratio on the Thermal Performance of Wavy Finned Absorber Solar Air Heater
A theoretical investigation on the effect of collector aspect ratio on the thermal performance of wavy finned absorber solar air heaters has been performed. For the constant collector area, the various performance parameters have been calculated for plane and wavy finned solar air heaters. It has been found that the performance of wavy finned solar air heater improved with the increase in the collector aspect ratio. The performance of wavy finned solar air heater has been found 30 percent higher than those of plane solar air heater. The obtained results for wavy fin solar air heaters are compared with the available experimental data of most common type solar air heaters.
Wavy fin, aspect ratio, solar air heater, thermal efficiency, collector efficiency factor, temperature rise.
Performance Comparison of AODV and Soft AODV Routing Protocol
A mobile ad hoc network (MANET) represents a system of wireless mobile nodes that can self-organize freely and dynamically into arbitrary and temporary network topology. Unlike a wired network, wireless network interface has limited transmission range. Routing is the task of forwarding data packets from source to a given destination. Ad-hoc On Demand Distance Vector (AODV) routing protocol creates a path for a destination only when it required. This paper describes the implementation of AODV routing protocol using MATLAB-based Truetime simulator. In MANET's node movements are not fixed while they are random in nature. Hence intelligent techniques i.e. fuzzy and ANFIS are used to optimize the transmission range. In this paper, we compared the transmission range of AODV, fuzzy AODV and ANFIS AODV. For soft computing AODV, we have taken transmitted power and received threshold as input and transmission range as output. ANFIS gives better results as compared to fuzzy AODV.
ANFIS, AODV, fuzzy, MANET, reactive routing protocol, routing protocol, Truetime.
Investigation of Flame and Soot Propagation in Non-Air Conditioned Railway Locomotives
Propagation of fire through a non-air conditioned
railway compartment is studied by virtue of numerical simulations.
Simultaneous computational fire dynamics equations, such as
Navier-Stokes, lumped species continuity, overall mass and energy
conservation, and heat transfer are solved using finite volume based
(for radiation) and finite difference based (for all other equations)
solver, Fire Dynamics Simulator (FDS). A single coupe with an eight
berth occupancy is used to establish the numerical model, followed
by the selection of a three coupe system as the fundamental unit
of the locomotive compartment. Heat Release Rate Per Unit Area
(HRRPUA) of the initial fire is varied to consider a wide range of
compartmental fires. Parameters, such as air inlet velocity relative
to the locomotive at the windows, the level of interaction with the
ambiance and closure of middle berth are studied through a wide
range of numerical simulations. Almost all the loss of lives and
properties due to fire breakout can be attributed to the direct or
indirect exposure to flames or to the inhalation of toxic gases and
resultant suffocation due to smoke and soot. Therefore, the temporal
stature of fire and smoke are reported for each of the considered
cases which can be used in the present or extended form to develop
guidelines to be followed in case of a fire breakout.
Fire dynamics, flame propagation, locomotive fire,
soot flow pattern.
Study of Icons in Enterprise Application Software Context
Icons are not merely decorative elements in enterprise applications but very often used because of their many advantages such as compactness, visual appeal, etc. Despite these potential advantages, icons often cause usability problems when they are designed without consideration for their many potential downsides. The aim of the current study was to examine the effect of articulatory distance – the distance between the physical appearance of an interface element and what it actually means. In other words, will the subject find the association of the function and its appearance on the interface natural or is the icon difficult for them to associate with its function. We have calculated response time and quality of identification by varying icon concreteness, the context of usage and subject experience in the enterprise context. The subjects were asked to associate icons (prepared for study purpose) with given function options in context and out of context mode. Response time and their selection were recorded for analysis.
Icons, icon concreteness, icon recognition, HCI.
Numerical Simulations of Fire in Typical Air Conditioned Railway Coach
Railways in India remain primary mode of transport
having one of the largest networks in the world and catering to
billions of transits yearly. Catastrophic economic damage and loss
to life is encountered over the past few decades due to fire to
locomotives. Study of fire dynamics and fire propagation plays an
important role in evacuation planning and reducing losses. Simulation
based study of propagation of fire and soot inside an air conditioned
coach of Indian locomotive is done in this paper. Finite difference
based solver, Fire Dynamic Simulator (FDS) version 6 has been
used for analysis. A single air conditioned 3 tier coupe closed to
ambient surroundings by glass windows having occupancy for 8
people is the basic unit of the domain. A system of three such
coupes combined is taken to be fundamental unit for the entire
study to resemble effect to an entire coach. Analysis of flame and
soot contours and concentrations is done corresponding to variations
in heat release rate per unit volume (HRRPUA) of fire source,
variations in conditioned air velocity being circulated inside coupes
by vents and an alternate fire initiation and propagation mechanism
via ducts. Quantitative results of fractional area in top and front
view of the three coupes under fire and smoke are obtained using
MATLAB (IMT). Present simulations and its findings will be useful
for organizations like Commission of Railway Safety and others in
designing and implementing safety and evacuation measures.
Air-conditioned coaches, fire propagation, flame
contour, soot flow, train fire.
Study of Fire Propagation and Soot Flow in a Pantry Car of Railway Locomotive
Fire accidents in trains bring huge disaster to human
life and property. Evacuation becomes a major challenge in such
incidents owing to confined spaces, large passenger density and
trains moving at high speeds. The pantry car in Indian Railways
trains carry inflammable materials like cooking fuel and LPG and
electrical fittings. The pantry car is therefore highly susceptible to
fire accidents. Numerical simulations have been done in a pantry car
of Indian locomotive train using computational fluid dynamics based
software. Different scenarios of a fire outbreak have been explored
by varying Heat Release Rate per Unit Area (HRRPUA) of the fire
source, introduction of exhaust in the cooking area, and taking a
case of an air conditioned pantry car. Temporal statures of flame and
soot have been obtained for each scenario and differences have been
studied and reported. Inputs from this study can be used to assess
casualties in fire accidents in locomotive trains and development of
smoke control/detection systems in Indian trains.
Fire propagation, flame contour, pantry fire, soot flow.
Influence of Channel Depth on the Performance of Wavy Fin Absorber Solar Air Heater
Channel depth is an important design parameter to be fixed in designing a solar air heater. In this paper, a mathematical model has been developed to study the influence of channel duct on the thermal performance of solar air heaters. The channel depth has been varied from 1.5 cm to 3.5 cm for the mass flow range 0.01 to 0.11 kg/s. Based on first law of thermodynamics, the channel depth of 1.5 cm shows better thermal performance for all the mass flow range. Also, better thermohydraulic performance has been found up to 0.05 kg/s, and beyond this, thermohydraulic efficiency starts decreasing. It has been seen that, with the increase in the mass flow rate, the difference between thermal and thermohydraulic efficiency increases because of the increase in pressure drop. At lower mass flow rate, 0.01 kg/s, the thermal and thermohydraulic efficiencies for respective channel depth remain the same.
Channel depth, thermal efficiency, wavy fin, thermohydraulic efficiency.
Single Phase Fluid Flow in Series of Microchannel Connected via Converging-Diverging Section with or without Throat
Single phase fluid flow through series of uniform microchannels connected via transition section (converging-diverging section with or without throat) was analytically and numerically studied to characterize the flow within the channel and in the transition sections. Three sets of microchannels of diameters 100, 184, and 249 μm were considered for investigation. Each set contains 10 numbers of microchannels of length 20 mm, connected to each other in series via transition sections. Transition section consists of either converging-diverging section with throat or without throat. The effect of non-uniformity in microchannels on pressure drop was determined by passing water/air through the set of channels for Reynolds number 50 to 1000. Compressibility and rarefaction effects in transition sections were also tested analytically and numerically for air flow. The analytical and numerical results show that these configurations can be used in enhancement of transport processes. However, converging-diverging section without throat shows superior performance over with throat configuration.
Contraction-expansion flow, integrated microchannel, microchannel network, single phase flow.
Three-Dimensional, Non-Linear Finite Element Analysis of Bullet Penetration through Thin AISI 4340 Steel Target Plate
Bullet penetration in steel plate is investigated with
the help of three-dimensional, non-linear, transient, dynamic, finite
elements analysis using explicit time integration code LSDYNA. The
effect of large strain, strain-rate and temperature at very high velocity
regime was studied from number of simulations of semi-spherical
nose shape bullet penetration through single layered circular plate
with 2 mm thickness at impact velocities of 500, 1000, and 1500 m/s
with the help of Johnson Cook material model. Mie-Gruneisen
equation of state is used in conjunction with Johnson Cook material
model to determine pressure-volume relationship at various points of
interests. Two material models viz. Plastic-Kinematic and Johnson-
Cook resulted in different deformation patterns in steel plate. It is
observed from the simulation results that the velocity drop and loss of
kinetic energy occurred very quickly up to perforation of plate, after
that the change in velocity and changes in kinetic energy are
negligibly small. The physics behind this kind of behaviour is
presented in the paper.
AISI 4340 steel, ballistic impact simulation, bullet
penetration, non-linear FEM.
The Impact of Female Characters on a Movie’s Return on Investment
In the age and times where women’s empowerment is a significant topic of discussion, we aim to analyze the potential gender diversity influence on box office revenues. The following research is carried out by collecting data from 400 Hollywood movies between the years 2014-2017 and performing regression analysis to find a correlation between the presence of female characters in movies and their return on investment (ROI). The paper finds that there is a positive relationship between the performance of the movies (its ROI) and the gender diversity i.e. the more the number of female characters, the higher the revenue generated. Another factor such as Number of Votes also has a direct impact on the revenue of the movie. The research not only takes into consideration the mere presence of women on screen but also the exchange of at least one dialogue among themselves, which is presented by the Bechdel Score of the movie.
Bechdel, diversity, Hollywood, return on investment.