In distributed system, the coordinator is needed to manage the use of the resources in the shared environment. Many algorithms have been proposed for the same. They have various positive and negative parts. Here we will discuss those issues which ensure the efficiency of the algorithm for election leader. Here a comparison will be provided to show the advantages and disadvantages of different election algorithms. The comparison would be based on the number of messages passing and the order of time complexity.
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Identifying Valid Email Spam Emails Using Decision TreeEditor IJCATR
The increasing use of e-mail and the growing trend of Internet users sending unsolicited bulk e-mail, the need for an antispam
filtering or have created, Filter large poster have been produced in this area, each with its own method and some parameters are
to recognize spam. The advantage of this method is the simultaneous use of two algorithms decision tree ID3 - Mamdani and Naive
Bayesian is fuzzy. The first two algorithms are then used to detect spam Bagging approach is to identify spam. In the evaluation of this
dataset contains a thousand letters have been analyzed by the software Weka charts provided in spam detection accuracy than previous
methods of improvement
Enhancing AODV Routing Protocol to Eliminate Black Hole Attack in MANET.......................................1
Ei Ei Khin and Thandar Phyu
Adaptive Search Information Technology in the University Library ........................................................ 15
Andriy Andrukhiv and Dmytro Tarasov
Educational Data Mining: Performance Evaluation of Decision Tree and Clustering Techniques Using
WEKA Platform........................................................................................................................................... 26
Ritika Saxena
Hamiltonian cycle in graphs 흈4 ≥ ퟐn....................................................................................................... 38
Nguyen Huu Xuan Truong and Vu Dinh Hoa
Automatic signature verification with chain code using weighted distance and ...eSAT Journals
Abstract The signature forgery can be restricted by either online or offline signature verification techniques. It verifies the signature by
performing a match with the pre-processed signature dynamically by detecting the motion of stylus during signature while on
other hand, offline verifies by performing a match using the two dimensional scanned image of the signature. This paper studies
about the various techniques available in offline signature verification along with their shadows.
Keywords: Signature Verification, Weighted Distance, High Pressure Factor, Normalization, Threshold Value
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
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Best COSC2536/2537 Security in Computing and Information Technology Assignments Help is now at essaycorp.Our professionals’ writers are here to help you with your information technology assignments.essaycorp assignment writing services are widespread across the US, UK, Australia, New Zealand, and other countries. Hurry up and get an exciting discount on your first order!
Identifying Valid Email Spam Emails Using Decision TreeEditor IJCATR
The increasing use of e-mail and the growing trend of Internet users sending unsolicited bulk e-mail, the need for an antispam
filtering or have created, Filter large poster have been produced in this area, each with its own method and some parameters are
to recognize spam. The advantage of this method is the simultaneous use of two algorithms decision tree ID3 - Mamdani and Naive
Bayesian is fuzzy. The first two algorithms are then used to detect spam Bagging approach is to identify spam. In the evaluation of this
dataset contains a thousand letters have been analyzed by the software Weka charts provided in spam detection accuracy than previous
methods of improvement
Enhancing AODV Routing Protocol to Eliminate Black Hole Attack in MANET.......................................1
Ei Ei Khin and Thandar Phyu
Adaptive Search Information Technology in the University Library ........................................................ 15
Andriy Andrukhiv and Dmytro Tarasov
Educational Data Mining: Performance Evaluation of Decision Tree and Clustering Techniques Using
WEKA Platform........................................................................................................................................... 26
Ritika Saxena
Hamiltonian cycle in graphs 흈4 ≥ ퟐn....................................................................................................... 38
Nguyen Huu Xuan Truong and Vu Dinh Hoa
Automatic signature verification with chain code using weighted distance and ...eSAT Journals
Abstract The signature forgery can be restricted by either online or offline signature verification techniques. It verifies the signature by
performing a match with the pre-processed signature dynamically by detecting the motion of stylus during signature while on
other hand, offline verifies by performing a match using the two dimensional scanned image of the signature. This paper studies
about the various techniques available in offline signature verification along with their shadows.
Keywords: Signature Verification, Weighted Distance, High Pressure Factor, Normalization, Threshold Value
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Sensing Trending Topics in Twitter for Greater Jakarta Area IJECEIAES
Information and communication technology grows so fast nowadays, especially related to the internet. Twitter is one of internet applications that produce a large amount of textual data called tweets. The tweets may represent real-world situation discussed in a community. Therefore, Twitter can be an important media for urban monitoring. The ability to monitor the situations may guide local government to respond quickly or make public policy. Topic detection is an important automatic tool to understand the tweets, for example, using non-negative matrix factorization. In this paper, we conducted a study to implement Twitter as a media for the urban monitoring in Jakarta and its surrounding areas called Greater Jakarta. Firstly, we analyze the accuracy of the detected topics in term of their interpretability level. Next, we visualize the trend of the topics to identify popular topics easily. Our simulations show that the topic detection methods can extract topics in a certain level of accuracy and draw the trends such that the topic monitoring can be conducted easily.
S IMULATION B ASED S TUDY OF C OOPERATIVE B LACK H OLE A TTACK R ESOLU...pijans
An Ad hoc Network is a pool of wireless mobile node
s energetically forming a network without the use o
f
any pre-accessible network infrastructure or centra
lized administrator. These nodes communicate with
each other by hop-to-hop communication. This dynami
c topology of mobile ad-hoc networks (MANETs)
allows nodes to get attached and leave the network
at any second of time. Thus MANET can be used in a
variety of fields. Current MANETs are designed prim
ary for military utility. This generic characterist
ic of
MANET has rendered its vulnerability to security at
tacks. Due to which unprotected attacks of the
malicious nodes can occur at any time. This paper f
ocuses on one such attack known as “Black hole
attack” and the routing protocol being used here is
AODV
Data Integrity Techniques: Aviation Best Practices for CRC & Checksum Error D...Philip Koopman
Author: Prof. Philip Koopman, Carnegie Mellon University
Abstract:
This talk includes both a tutorial and explanation of research results on the proper use of Cyclic Redundancy codes (CRCs) and checksums in an aviation context. More than 50 years since the invention of the CRC, the proper use of these error detection codes is still hampered by a combination of misleading folklore, sub-optimality of standard approaches, general inaccessibility of research results, and the occasional typographical error in key reference materials. However, recent work has been able to exhaustively explore the CRC design space and identify optimal selection criteria based on key system characteristics. This talk will covers the following areas: checksum and CRC theory with an emphasis on intuitive understanding rather than heavy math; why using a standard or widely used CRC can be suboptimal (or worse); how to pick a good checksum/CRC; the key parameters that affect the error detection capability of a checksum/CRC; CRC pitfalls illustrated via examples from Controller Area Network and ARINC-825; an example CRC selection process for achieving a required level of functional criticality; and a “seven deadly sins” list for CRC/checksum use. Some key research findings that are discussed include: a well-chosen CRC is usually dramatically better than a checksum for relatively little additional computational cost; you can usually do a lot better than “standard” CRC (especially CRC-32); Hamming Distance at the target payload length is the predominant selection criterion of interest; and it is important to avoid bit encoding approaches that undermine CRC effectiveness.
Bio:
Dr. Philip Koopman is a professor at Carnegie Mellon University, with research interests in the areas of software robustness, embedded networking, dependable embedded computer systems, and autonomous vehicle safety. Previously, he was a US Navy submarine officer, an embedded CPU architect for Harris Semiconductor, and an embedded system researcher at United Technologies. In addition to a variety of academic publications and two dozen patents, he has authored the book Better Embedded System Software based on lessons learned from more than a hundred design reviews of industry software. He has affiliations with both the Carnegie Mellon Electrical & Computer Engineering Department (ECE) and the National Robotics Engineering Center (NREC). He is a senior member of IEEE, senior member of the ACM, and a member of IFIP WG 10.4 on Dependable Computing and Fault Tolerance.
There are many distributed systems which use a leader in their logic. When such systems need to be fault
tolerant and the current leader suffers a technical problem, it is necesary to apply a special algorithm in
order to choose a new leader. In this paper I present a new fault tolerant algorithm which elects a new
leader based on a random roulette wheel selection.
FAULT TOLERANT LEADER ELECTION IN DISTRIBUTED SYSTEMSijcseit
There are many distributed systems which use a leader in their logic. When such systems need to be fault
tolerant and the current leader suffers a technical problem, it is necesary to apply a special algorithm in
order to choose a new leader. In this paper I present a new fault tolerant algorithm which elects a new
leader based on a random roulette wheel selection.
There are many distributed systems which use a leader in their logic. When such systems need to be fault tolerant and the current leader suffers a technical problem, it is necesary to apply a special algorithm in order to choose a new leader. In this paper I present a new fault tolerant algorithm which elects a new leader based on a random roulette wheel selection
The leader algorithm (Horrigan [394]) represents each cluster using a.pdfmallik3000
The leader algorithm (Horrigan [394]) represents each cluster using a point, known as a leader,
and assigns each point to the cluster corresponding to the closest leader, unless this distance is
above a user-specified threshold. In that case, the point becomes the leader of a new cluster.
What are the advantages and disadvantages of the leader algorithm as compared to K-means?
Suggest ways in which the leader algorithm might be improved.
Solution
(a)K-Means Clustering Advantages and Disadvantages
K-Means Advantages:
1) If variables are enormous, then K-Means the majority of the times computationally faster than
hierarchical clustering, if we stay k smalls.
2) K-Means create tighter clusters than hierarchical clustering, particularly if the clusters are
globular.
K-Means Disadvantages:
1) Hard to predict K-Value.
2) With global cluster, it didn\'t work fine.
3) Dissimilar initial partitions can result in dissimilar final clusters.
4) It does not work fine with clusters of dissimilar size and dissimilar density.
(b)Definition:
The difficulty of leader election is for each processor finally to decide that whether it is a leader
or not subject to merely one processor decides that it is the leader. An algorithm resolves the
leader election difficulty if:
States of processors are alienated into elected and not elected states. Once chosen, it remains as
elected.
In every implementation, precisely one processor becomes elected and the rest decide that they
are not elected.
A suitable leader election algorithm must convene the following conditions:
Termination: the algorithm should finish eventually within a finite time one leader is selected. In
randomized approaches this condition is sometimes weakened
Uniqueness: there is exactly one processor that considers itself as leader.
Agreement: all other processors know who the leader is.
An algorithm for leader election may vary in following aspects:
Communication mechanism: the processors are either synchronous in which processes are
synchronized by a clock signal or asynchronous where processes run at arbitrary speeds.
Process names: whether processes have a unique identity or are indistinguishable.
Network topology: for instance, ring, acyclic graph or complete graph.
Size of the network: the algorithm may or may not use knowledge of the number of processes in
the system.
Algorithms:
Leader election in rings:
Ring network topology
A ring network is a connected-graph topology in which each node is exactly connected to two
other nodes, i.e., for a graph with n nodes, there are exactly n edges connecting the nodes. A ring
can be unidirectional, which means processors only communicate in one direction, or
bidirectional, meaning processors may transmit and receive messages in both directions.
Anonymous rings:
A ring is said to be anonymous if every processor is identical. More formally, the system has the
same state machine for every processor. There is no deterministic algorithm to elect a leader in
anonym.
Sensing Trending Topics in Twitter for Greater Jakarta Area IJECEIAES
Information and communication technology grows so fast nowadays, especially related to the internet. Twitter is one of internet applications that produce a large amount of textual data called tweets. The tweets may represent real-world situation discussed in a community. Therefore, Twitter can be an important media for urban monitoring. The ability to monitor the situations may guide local government to respond quickly or make public policy. Topic detection is an important automatic tool to understand the tweets, for example, using non-negative matrix factorization. In this paper, we conducted a study to implement Twitter as a media for the urban monitoring in Jakarta and its surrounding areas called Greater Jakarta. Firstly, we analyze the accuracy of the detected topics in term of their interpretability level. Next, we visualize the trend of the topics to identify popular topics easily. Our simulations show that the topic detection methods can extract topics in a certain level of accuracy and draw the trends such that the topic monitoring can be conducted easily.
S IMULATION B ASED S TUDY OF C OOPERATIVE B LACK H OLE A TTACK R ESOLU...pijans
An Ad hoc Network is a pool of wireless mobile node
s energetically forming a network without the use o
f
any pre-accessible network infrastructure or centra
lized administrator. These nodes communicate with
each other by hop-to-hop communication. This dynami
c topology of mobile ad-hoc networks (MANETs)
allows nodes to get attached and leave the network
at any second of time. Thus MANET can be used in a
variety of fields. Current MANETs are designed prim
ary for military utility. This generic characterist
ic of
MANET has rendered its vulnerability to security at
tacks. Due to which unprotected attacks of the
malicious nodes can occur at any time. This paper f
ocuses on one such attack known as “Black hole
attack” and the routing protocol being used here is
AODV
Data Integrity Techniques: Aviation Best Practices for CRC & Checksum Error D...Philip Koopman
Author: Prof. Philip Koopman, Carnegie Mellon University
Abstract:
This talk includes both a tutorial and explanation of research results on the proper use of Cyclic Redundancy codes (CRCs) and checksums in an aviation context. More than 50 years since the invention of the CRC, the proper use of these error detection codes is still hampered by a combination of misleading folklore, sub-optimality of standard approaches, general inaccessibility of research results, and the occasional typographical error in key reference materials. However, recent work has been able to exhaustively explore the CRC design space and identify optimal selection criteria based on key system characteristics. This talk will covers the following areas: checksum and CRC theory with an emphasis on intuitive understanding rather than heavy math; why using a standard or widely used CRC can be suboptimal (or worse); how to pick a good checksum/CRC; the key parameters that affect the error detection capability of a checksum/CRC; CRC pitfalls illustrated via examples from Controller Area Network and ARINC-825; an example CRC selection process for achieving a required level of functional criticality; and a “seven deadly sins” list for CRC/checksum use. Some key research findings that are discussed include: a well-chosen CRC is usually dramatically better than a checksum for relatively little additional computational cost; you can usually do a lot better than “standard” CRC (especially CRC-32); Hamming Distance at the target payload length is the predominant selection criterion of interest; and it is important to avoid bit encoding approaches that undermine CRC effectiveness.
Bio:
Dr. Philip Koopman is a professor at Carnegie Mellon University, with research interests in the areas of software robustness, embedded networking, dependable embedded computer systems, and autonomous vehicle safety. Previously, he was a US Navy submarine officer, an embedded CPU architect for Harris Semiconductor, and an embedded system researcher at United Technologies. In addition to a variety of academic publications and two dozen patents, he has authored the book Better Embedded System Software based on lessons learned from more than a hundred design reviews of industry software. He has affiliations with both the Carnegie Mellon Electrical & Computer Engineering Department (ECE) and the National Robotics Engineering Center (NREC). He is a senior member of IEEE, senior member of the ACM, and a member of IFIP WG 10.4 on Dependable Computing and Fault Tolerance.
There are many distributed systems which use a leader in their logic. When such systems need to be fault
tolerant and the current leader suffers a technical problem, it is necesary to apply a special algorithm in
order to choose a new leader. In this paper I present a new fault tolerant algorithm which elects a new
leader based on a random roulette wheel selection.
FAULT TOLERANT LEADER ELECTION IN DISTRIBUTED SYSTEMSijcseit
There are many distributed systems which use a leader in their logic. When such systems need to be fault
tolerant and the current leader suffers a technical problem, it is necesary to apply a special algorithm in
order to choose a new leader. In this paper I present a new fault tolerant algorithm which elects a new
leader based on a random roulette wheel selection.
There are many distributed systems which use a leader in their logic. When such systems need to be fault tolerant and the current leader suffers a technical problem, it is necesary to apply a special algorithm in order to choose a new leader. In this paper I present a new fault tolerant algorithm which elects a new leader based on a random roulette wheel selection
The leader algorithm (Horrigan [394]) represents each cluster using a.pdfmallik3000
The leader algorithm (Horrigan [394]) represents each cluster using a point, known as a leader,
and assigns each point to the cluster corresponding to the closest leader, unless this distance is
above a user-specified threshold. In that case, the point becomes the leader of a new cluster.
What are the advantages and disadvantages of the leader algorithm as compared to K-means?
Suggest ways in which the leader algorithm might be improved.
Solution
(a)K-Means Clustering Advantages and Disadvantages
K-Means Advantages:
1) If variables are enormous, then K-Means the majority of the times computationally faster than
hierarchical clustering, if we stay k smalls.
2) K-Means create tighter clusters than hierarchical clustering, particularly if the clusters are
globular.
K-Means Disadvantages:
1) Hard to predict K-Value.
2) With global cluster, it didn\'t work fine.
3) Dissimilar initial partitions can result in dissimilar final clusters.
4) It does not work fine with clusters of dissimilar size and dissimilar density.
(b)Definition:
The difficulty of leader election is for each processor finally to decide that whether it is a leader
or not subject to merely one processor decides that it is the leader. An algorithm resolves the
leader election difficulty if:
States of processors are alienated into elected and not elected states. Once chosen, it remains as
elected.
In every implementation, precisely one processor becomes elected and the rest decide that they
are not elected.
A suitable leader election algorithm must convene the following conditions:
Termination: the algorithm should finish eventually within a finite time one leader is selected. In
randomized approaches this condition is sometimes weakened
Uniqueness: there is exactly one processor that considers itself as leader.
Agreement: all other processors know who the leader is.
An algorithm for leader election may vary in following aspects:
Communication mechanism: the processors are either synchronous in which processes are
synchronized by a clock signal or asynchronous where processes run at arbitrary speeds.
Process names: whether processes have a unique identity or are indistinguishable.
Network topology: for instance, ring, acyclic graph or complete graph.
Size of the network: the algorithm may or may not use knowledge of the number of processes in
the system.
Algorithms:
Leader election in rings:
Ring network topology
A ring network is a connected-graph topology in which each node is exactly connected to two
other nodes, i.e., for a graph with n nodes, there are exactly n edges connecting the nodes. A ring
can be unidirectional, which means processors only communicate in one direction, or
bidirectional, meaning processors may transmit and receive messages in both directions.
Anonymous rings:
A ring is said to be anonymous if every processor is identical. More formally, the system has the
same state machine for every processor. There is no deterministic algorithm to elect a leader in
anonym.
A wireless sensor network (WSN) consists of multiple sensor nodes and base stations that collect information from widely deployed sensors. However, the disadvantage is that WSNs are randomly distributed in an open environment, which makes them difficult to manage individually and more easily found and compromised by an attacker. An attacker can execute a false report insertion or invalid vote insertion attack through a compromised node. The Probabilistic Voting Filtering System (PVFS) is a system that prevents these two types of attacks. Before sending a report, the proposed method probabilistically selects a validation node, determines the validity of the report, and filters the report based on the thresholds that have been set. In this paper, the proposed scheme improves the lifetime, detection rate, and report delivery rate of the entire network by increasing the lifetime of the cluster head (CH) by selecting the numbers of message authentication codes (MACs) and verification nodes of the report. Using this system, the event detection rate and the network lifetime are improved by up to 18% and 6%, respectively, relative to the existing PVFS.
WSN LIFETIME EXTENSION USING GA OPTIMISED FUZZY LOGICijcsit
A wireless sensor network (WSN) consists of multiple sensor nodes and base stations that collect information from widely deployed sensors. However, the disadvantage is that WSNs are randomly distributed in an open environment, which makes them difficult to manage individually and more easily found and compromised by an attacker. An attacker can execute a false report insertion or invalid vote insertion attack through a compromised node. The Probabilistic Voting Filtering System (PVFS) is a system that prevents these two types of attacks. Before sending a report, the proposed method probabilistically selects a validation node, determines the validity of the report, and filters the report based on the thresholds that have been set. In this paper, the proposed scheme improves the lifetime, detection rate, and report delivery rate of the entire network by increasing the lifetime of the cluster head (CH) by selecting the numbers of message authentication codes (MACs) and verification nodes of the report. Using this system, the event detection rate and the network lifetime are improved by up to 18% and 6%, respectively, relative to the existing PVFS.
Similar to Leader Election Approach: A Comparison and Survey (20)
Performance of Wideband Mobile Channel with Perfect Synchronism BPSK vs QPSK ...Editor Jacotech
Direct-sequence code-division multiple access (DS-CDMA) is
currently the subject of much research as it is a promising
multiple access capability for third and fourth generations
mobile communication systems. The synchronous DS-CDMA
system is well known for eliminating the effects of multiple
access interference (MAI) which limits the capacity and
degrades the BER performance of the system. In this paper,
we investigate the bit error rate (BER) performance of a
synchronous DS-CDMA system over a wideband mobile
radio channel. The BER performance is affected by the
difference in path length ΔL and the number of arriving
signals N. Furthermore, the effect of these parameters is
examined on the synchronous DS-CDMA system for different
users’ number as well as different processing gain Gp. In this
environment and under the above conditions the performances
of the BPSK (Binary Phase Shift Keying) and the QPSK
(Quadrature Phase Shift Keying) modulations are compared.
The promising simulation results showed the possibility of
applying this system to the wideband mobile radio channel.
MOVIE RATING PREDICTION BASED ON TWITTER SENTIMENT ANALYSISEditor Jacotech
With microblogging platforms such as Twitter generating
huge amounts of textual data every day, the possibilities of
knowledge discovery through Twitter data becomes
increasingly relevant. Similar to the public voting mechanism
on websites such as the Internet Movie Database (IMDb) that
aggregates movies ratings, Twitter content contains
reflections of public opinion about movies. This study aims to
explore the use of Twitter content as textual data for
predicting the movie rating. In this study, we extract number
of tweets and compiled to predict the rating scores of newly
released movies. Predictions were done with the algorithms,
exploring the tweet polarity. In addition, this study explores
the use of several different kinds of tweet classification
Algorithm and movie rating algorithm. Results show that
movie rating developed by our application is compared to
IMDB and Rotten Tomatoes.
Non integer order controller based robust performance analysis of a conical t...Editor Jacotech
The design of robust controller for any non linear process is a
challenging task because of the presence of various types of
uncertainties. In this paper, various design methods of robust
PID controller for the level control of conical tank are
discussed. Uncertainties are of different types, among that
structured uncertainty of 30% is introduced to the nominal
plant for analysing the robustness. As a first step, the control
of level is done by using conventional integer order controller
for both nominal and uncertain system. Then, the control is
done by means of Fractional Order Proportional Integral
Derivative (FOPID) controller for achieving robustness. With
the help of time series parameters, a comparison is made
between conventional PID and FOPID with respect to the
simulated output using MATLAB and also analyzed the
robustness.
FACTORS CAUSING STRESS AMONG FEMALE DOCTORS (A COMPARATIVE STUDY BETWEEN SELE...Editor Jacotech
It is an important task of working women to handle two
important tasks. Balancing these two roles at home and
work is very challenging task and causes stress at different
levels. Different dimension of working women’s life
involves in evolving the stress in working women’s life.
These stresses cause the imbalance at the front of and
handling family responsibility. In the current scenario,
doctors face many stressors that are peculiar to the medical
profession and doctors are required to have more
competencies than before in diagnosis ongoing
management of medical conditions. This means increased
responsibilities which may contribute to stress. Stress
experienced at work can have adverse outcomes for the
well-being of individual employees and organization as
whole. My study is focusing on identifying the factors
causing stress among female doctors working for public
and private hospitals and their stress levels associations
with respect to sector. A sample of 300 female doctors
from urban area participated in this study. Out of this, 150
each are from public and private hospitals respectively. A
self-made standardized tool was administered based on five
point scale. Results indicates that the values were found to
be 0.000 in all the cases except, psychosomatic problems
(0.004) which is lesser than (0.05) p-value resulting into
rejection of null hypotheses , consequently revealing an
association between sector of female doctors and stress due
to workload, working condition, physical exertion,
emotional exhaustion, job security, organizational support,
work family conflict, family adjustment, task demands,
psychosomatic problems, patient’s expectation and working
hours.
ANALYSIS AND DESIGN OF MULTIPLE WATERMARKING IN A VIDEO FOR AUTHENTICATION AN...Editor Jacotech
Watermarking technique be employ instance & for a second time for
validation and protection of digital data (images, video and audio
files, digital repositories and libraries, web publishing). It is helpful
to copyright protection and illegal copying of digital data like video
frames and making digital data more robust and imperceptible. With
the advent of internet, creation and delivery of digital data has grown
many fold. In that Scenario has to need a technique for transferring
digital data securely without changing their originality and
robustness. In this paper proposed a plan of latest watermarking
method which involves inserting and adding two or more digital data
or pictures in a single video frame for the principle of protection and
replicate the similar procedure for N no video frames for
authentication of entire digital video. After that digital video is
encrypted and decrypted by using motion vector bit-xor encryption
and decryption technique.
The Impact of Line Resistance on the Performance of Controllable Series Compe...Editor Jacotech
In recent years controllable FACTS devices are increasingly
integrated into the transmission system. FACTS devices that
provide series control such as Controllable Series Compensator
(CSC) has significant effect on the voltage stability of Electric
Power system. In this work impact of line resistance on the
performance of CSC in a single-load infinitive-bus (SLIB)
model is investigated. The proposed framework is applied to
SLIB model and obtained results demonstrates that line
resistance has considerable effect on voltage stability limits and
performance of CSC.
Security Strength Evaluation of Some Chaos Based Substitution-BoxesEditor Jacotech
Recently, handful amount of S-boxes, using the various
methods such as affine transformations, gray coding,
optimization, chaotic systems, etc, have been suggested. It is
prudent to use cryptographically strong S-boxes for the design
of powerful ciphers. In this paper, we sampled some widely
used 8×8 S-boxes which are recently synthesized and security
analysis and evaluation is executed to uncover the best
candidate(s). The performance analysis is exercised against
the crucial measures like nonlinearity, linear approximation
probability, algebraic immunity, algebraic complexity,
differential uniformity. These parameters are custom selected
because their scores decide the security strength against
cryptographic assaults like linear cryptanalysis, algebraic
attacks, and differential cryptanalysis. The anticipated
analysis in this work facilitates the cryptographers, designers,
researchers to choose suitable candidate decided over many
parameters and can be engaged in modern block encryption
systems that solely rely on 8×8 S-box. Moreover, the analysis
assists in articulating efficient S-boxes and to evaluate the
attacks resistivity of their S-boxes.
Traffic Detection System is an Android application that aims at determining the behavior of traffic in a particular location. It calculates the speed of the vehicle and the level of congestion or the amount of traffic is determined on the basis of the values of sensors. If any such obstruct found, then the driver is provided an option to send messages regarding high traffic to his/her friends. After a distinct number of repeated low speed and breaks, the location of the vehicle (latitude and longitude) send to a pre-specified contact (selected in case of traffic congestion) through an SMS. This application uses the features of the Global positioning system. The Latitude, as well as the longitude of the location where traffic jams are formed, is sent to the friends of the user. The Goggle map of the location also sends to the friends. It uses the SMS Manager a functionality of Android. The friends receiving the messages will thereby avoid taking the congested route and hence the level of traffic on the congested road will decrease, and the friends will reach the destination in comparatively less time.
Performance analysis of aodv with the constraints of varying terrain area and...Editor Jacotech
Mobile Ad Hoc Networks (MANETs) are wireless networks,
where there is no requirement for any infrastructure support to
transfer data packets between mobile nodes. These nodes
communicate in a multi-hop mode; each mobile node acts
both as a host and router. The main job of Quality of Service
(QoS)[1][2] routing in MANETs is to search and establish
routes among different mobile nodes for satisfying QoS
requirements of wireless sensor networks as PDR, Average
end-to-end delay, Average Throughput. The QoS routing
protocols efficient for commercial, real-time and multimedia
applications are in demand for day to day activities[2].
Modeling of solar array and analyze the current transient response of shunt s...Editor Jacotech
Spacecraft bus voltage is regulated by power
conditioning unit using switching shunt voltage regulator having
solar array cells as the primary source of power. This source
switches between the bus loads and the shunt switch for fine
control of spacecraft bus voltage. The effect of solar array cell
capacitance [5][6] along with inductance and resistance of the
interface wires between solar cells and power conditioning
unit[1], generates damped sinusoidal currents superimposed on
the short circuit current of solar cell when shunted through
switch. The peak current stress on the shunt switch is to be
considered in the selection of shunt switch in power conditioning
unit. The analysis of current transients of shunt switch in PCU
considering actual spacecraft interface wire length by
illumination of solar panel (combination of series and parallel
solar cells) is difficult with hardware simulation. Software
simulation by modeling solar cell is carried out for a single string
(one parallel) in Pspice [6]. Since in spacecrafts number of
parallels and interface cable length are variable parameters the
analysis of current transients of shunt switch is carried out by
modeling solar array with the help of solar cell model[6] for the
actual spacecraft condition.
License plate recognition an insight to the proposed approach for plate local...Editor Jacotech
License Plate Recognition (LPR) system for vehicles is an innovative and a very challenging area for research due to the innumerous plate formats and the nonuniform outdoor illumination conditions during which images are acquired. Thus, most approaches developed, work under certain restrictions such as fixed illumination, stationary background and limited speed. Algorithms developed for LPR systems are generally composed of three significant stages: 1] localization of the license plate from an entire scene image; 2] segmentation of the characters on the plate; 3] recognition of each of the segmented characters. A simple approach for preprocessing of the images, localization and extraction phase has been described in this paper. Numerous procedures have been developed for LPR systems and are assessed in this paper taking into consideration issues like processing time, computational power and recognition rate wherever available.
Design of airfoil using backpropagation training with mixed approachEditor Jacotech
Levenberg-Marquardt back-propagation training method has some limitations associated with over fitting and local optimum problems. Here, we proposed a new algorithm to increase the convergence speed of Backpropagation learning to design the airfoil. The aerodynamic force coefficients corresponding to series of airfoil are stored in a database along with the airfoil coordinates. A feedforward neural network is created with aerodynamic coefficient as input to produce the airfoil coordinates as output. In the proposed algorithm, for output layer, we used the cost function having linear & nonlinear error terms then for the hidden layer, we used steepest descent cost function. Results indicate that this mixed approach greatly enhances the training of artificial neural network and may accurately predict airfoil profile.
Ant colony optimization based routing algorithm in various wireless sensor ne...Editor Jacotech
Wireless Sensor Network has several issues and challenges due to limited battery backup, limited computation capability, and limited computation capability. These issues and challenges must be taken care while designing the algorithms to increase the Network lifetime of WSN. Routing, the act of moving information across an internet world from a source to a destination is one of the vital issue associated with Wireless Sensor Network. The Ant Colony Optimization (ACO) algorithm is a probabilistic technique for solving computational problems that can be used to find optimal paths through graphs. The short route will be increasingly enhanced therefore become more attractive. The foraging behavior and optimal route finding capability of ants can be the inspiration for ACO based algorithm in WSN. The nature of ants is to wander randomly in search of food from their nest. While moving, ants lay down a pheromone trail on the ground. This chemical pheromone has the ability to evaporate with the time. Ants have the ability to smell pheromone. When selecting their path, they tend to select, probably the paths that has strong pheromone concentrations. As soon as an ant finds a food source, carries some of it back to the nest. While returning, the quantity of chemical pheromone that an ant lay down on the ground may depend on the quantity and quality of the food. The pheromone trails will lead other ants towards the food source. The path which has the strongest pheromone concentration is followed by the ant which is the shortest paths between their nest and food source. This paper surveys the ACO based routing in various Networking domains like Wireless Sensor Networks and Mobile Ad Hoc Networks.
An efficient ant optimized multipath routing in wireless sensor networkEditor Jacotech
Today, the Wireless Sensor Network is increasingly gaining popularity and importance. It is the more interesting and stimulating area of research. Now, the WSN is applied in object tracking and environmental monitoring applications. This paper presents the self-optimized model of multipath routing algorithm for WSN which considers definite parameters like delay, throughput level and loss and generates the outcomes that maximizes data throughput rate and minimizes delay and loss. This algorithm is based on ANT optimization technique that will bring out an optimal and organized route for WSN and is also to avoid congestion in WSN, the algorithm incorporate multipath capability..
A mobile monitoring and alert sms system with remote configuration – a case s...Editor Jacotech
One of the parent´s main concerns nowadays it to know their children´s whereabouts. Some applications exist to address this issue and most of them rely on internet connection which makes the solution expensive. In this paper we present a low cost solution, based on SMS, and with the ability to remotely configure the child monitoring process. We also present the architecture and the full flowchart of the child application whenever a SMS is received. This case study uses Android and the more recent location API – the Fused Location Provider. For obvious reasons, the security issue has been a concern, which resulted in a configuration module in the child application to specify authorized senders
Leader election approach a comparison and surveyEditor Jacotech
In distributed system, the coordinator is needed to manage the use of the resources in the shared environment. Many algorithms have been proposed for the same. They have various positive and negative parts. Here we will discuss those issues which ensure the efficiency of the algorithm for election leader. Here a comparison will be provided to show the advantages and disadvantages of different election algorithms. The comparison would be based on the number of messages passing and the order of time complexity
Modeling of solar array and analyze the current transientEditor Jacotech
Spacecraft bus voltage is regulated by power
conditioning unit using switching shunt voltage regulator having
solar array cells as the primary source of power. This source
switches between the bus loads and the shunt switch for fine
control of spacecraft bus voltage. The effect of solar array cell
capacitance [5][6] along with inductance and resistance of the
interface wires between solar cells and power conditioning
unit[1], generates damped sinusoidal currents superimposed on
the short circuit current of solar cell when shunted through
switch. The peak current stress on the shunt switch is to be
considered in the selection of shunt switch in power conditioning
unit. The analysis of current transients of shunt switch in PCU
considering actual spacecraft interface wire length by
illumination of solar panel (combination of series and parallel
solar cells) is difficult with hardware simulation. Software
simulation by modeling solar cell is carried out for a single string
(one parallel) in Pspice [6]. Since in spacecrafts number of
parallels and interface cable length are variable parameters the
analysis of current transients of shunt switch is carried out by
modeling solar array with the help of solar cell model[6] for the
actual spacecraft condition.
Traffic Detection System is an Android application that aims at determining the behavior of traffic in a particular location. It calculates the speed of the vehicle and the level of congestion or the amount of traffic is determined on the basis of the values of sensors. If any such obstruct found, then the driver is provided an option to send messages regarding high traffic to his/her friends. After a distinct number of repeated low speed and breaks, the location of the vehicle (latitude and longitude) send to a pre-specified contact (selected in case of traffic congestion) through an SMS. This application uses the features of the Global positioning system. The Latitude, as well as the longitude of the location where traffic jams are formed, is sent to the friends of the user. The Goggle map of the location also sends to the friends. It uses the SMS Manager a functionality of Android. The friends receiving the messages will thereby avoid taking the congested route and hence the level of traffic on the congested road will decrease, and the friends will reach the destination in comparatively less time.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Water billing management system project report.pdfKamal Acharya
Our project entitled “Water Billing Management System” aims is to generate Water bill with all the charges and penalty. Manual system that is employed is extremely laborious and quite inadequate. It only makes the process more difficult and hard.
The aim of our project is to develop a system that is meant to partially computerize the work performed in the Water Board like generating monthly Water bill, record of consuming unit of water, store record of the customer and previous unpaid record.
We used HTML/PHP as front end and MYSQL as back end for developing our project. HTML is primarily a visual design environment. We can create a android application by designing the form and that make up the user interface. Adding android application code to the form and the objects such as buttons and text boxes on them and adding any required support code in additional modular.
MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software. It is a stable ,reliable and the powerful solution with the advanced features and advantages which are as follows: Data Security.MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
1. Journal of Advanced Computing and Communication Technologies (ISSN: 2347 - 2804)
Volume No.3 Issue No. 2, April 2015
40
Leader Election Approach: A Comparison and Survey
By
Kshama Tiwari1
, Brajesh Kumar Umrao2
M. Tech. Scholar, Asst. Professor
Dept. of Computer Science and Engineering
UIT, Allahabad, India
tiwari.kshama@gmail.com, umraoniec@gmail.com
ABSTRACT
In distributed system, the coordinator is needed to manage the use of the
resources in the shared environment. Many algorithms have been
proposed for the same. They have various positive and negative parts.
Here we will discuss those issues which ensure the efficiency of the
algorithm for election leader. Here a comparison will be provided to
show the advantages and disadvantages of different election algorithms.
The comparison would be based on the number of messages passing
and the order of time complexity.
KEY WORDS
Coordinator, successor, electioneer, ordinary set, candidate set.
1. INTRODUCTION
Various distributed algorithms require that there be a unique
coordinator process in the entire system that is responsible to perform
various kinds of functions. Many persons have proposed a wide range
of election algorithms. The Bully algorithm is one of them, and it is one
of the oldest election algorithms. It reduces redundant elections,
minimizes message passing and network traffic. Here a comparative
analysis of various election algorithms is proposed, which is based on
different concepts like priority number, election commission, k
coordinator process, successor, heap tree, max heap, Fibonacci heap,
etc.
2. ELECTION ALGORITHM
Election algorithm is used to find the coordinator in the network in
distributed environments, as the coordinator is responsible for managing
the utilization of resources. Various algorithms require peer processes to
elect a leader or a coordinator. It is required to select a new leader if the
existing one fails to respond. Each process has a unique identification
number that helps to specify the priority of a process in the network. So
election algorithm gives the approach to find the new leader.
3. LITERATURE REVIEW
Bully algorithm proposed by Garcia-Molina for the coordinator
election, works on the assumption that the system uses time as a
parameter to detect process failure (the coordinator). All processes have
a unique number in the system and they know the process number of all
other processes. Once an election is held, a process with the highest
process number is elected as a coordinator, which is agreed by other
nodes (process). The Bully Algorithm has three types of messages: first
is election message sent to announce an election, second is an ok
message sent as the response to an election message, and third is victory
messages sent to announce the new coordinator among all other live
processes. When any node finds that the leader node has been crashed,
then it immediately announces itself as a new leader if no other higher
process id node exists. Otherwise it starts election process as bully
algorithm had proposed. There are some drawbacks of the bully
algorithm as whenever a crashed node becomes alive it starts election
process that gives an extra overhead to system resources. Next
drawback is the heavier number of repetitive election process,
especially in the worst case when the election is started by the lowest id
process. Then at least n-2 redundant election processes take place,
where n stands for the total no of live nodes. Another drawback is that
more than one process can start election parallel (no solution goes with
one), so many unwanted election processes take place. So the main
drawback of bully algorithm is the large number of messages passing
the order O (n2) [2].
So Mamun proposed a modified bully algorithm. The modified bully
algorithm has been proved better than the bully algorithm as in the
worst scenario when the lowest id node detects the failure of
coordinator node, the bully algorithm performs n-1 number of elections
to find the new coordinator, which takes O(n2
) messages to be passed.
Whereas in modified bully algorithm only O(n) messages are required
to be sent. Also, when the detector node finds itself as the next highest
node to the failure node then it directly declares itself as a coordinator
by sending n-2 coordinator messages, without passing any election
message. So in the worst case the bully algorithm requires O(n2
)
,whereas modified bully algorithm requires 2(n-1) messages [3]. By the
above comparison it is justified that modified bully algorithm is better
than the bully algorithm, but still it has some drawbacks as it doesn’t
provide any scope to cope with simultaneous detection of failure and
2. Journal of Advanced Computing and Communication Technologies (ISSN: 2347 - 2804)
Volume No.3 Issue No. 2, April 2015
41
election of new leader node. This number of messages sent can be
minimized further by using some latest data structures for nodes
arrangement.
So the improved method over modified bully election algorithm is the
modified election algorithm that reduces the number of messages to be
transmitted and reduces the traffic on the distributed environment. Thus,
the latter has proposed the concept of K coordinator group that
prevents the global election of coordinator redundantly, as the
coordinators after crashed nodes are already decided. The modified
election algorithm defines the coordinator group like-- {Coordinator1,
Alternative1, Alternative2 …Alternative k}. These alternative processes
from 1 to k are the processes with the next priority numbers to the
coordinator1.
So by using modified election algorithm a process with greatest number
is selected as coordinator, and then k-1 processes of coordination group
are selected. Now the process id of each coordinator in the group is sent
to all the processes, so when any process finds that the coordinator is
crashed, then it sends a message to alternative1 to inform that the
coordinator has been crashed. Then one of the following two situations
may arise: i) if alternative 1 is alive, ii) If alternative 1 is not alive. The
main idea is that it uses candidate nodes. The complexity of proposed
algorithm is O (n), whereas in bully algorithm it takes O (n2
) time. That
shows the modified algorithm is better than the previous one (bully
algorithm). There are several disadvantages associated with the
modified election algorithm—(i) it doesn’t guarantee to stop multiple
elections parallel, which imposes a heavy load on the network, ii) this
algorithm does not provide any solution when an electioneer node fails
during leader election [4].
Now there is another algorithm known as Enhanced Bully algorithm for
the leader election that has been proposed by Murshed. This algorithm
has proposed some modifications to Traditional Bully algorithm and the
Modified Bully Algorithm. Here the concept of set division has been
proposed, according to which the complete node set is divided into two
equal half sets where one is Candidate set, and another is Ordinary set.
Candidate set consists of N/2 Nodes. The other N/2 nodes are ordinary
nodes, as the node in the candidate set has higher id number than the
ordinary set nodes. Each node has the information about other node sets
and ids. Here the election message consists of the id of the failed node
and the failure detector node. The answer message consists of the node
ids of the leader and the complete candidate set. Here another concept
has also been proposed with the name tiebreaker time δ that stops
redundancy and unnecessary elections and helps to reduce the number
of messages required in the election of new node.
The election procedure is performed on the basis of the following
situations:
i. Ideal case (IC): This case arises when a node i in the
Ordinary set detects failure of the leader node then it
sends an election message to the set of candidate node
set and waits until it gets Ok message. On receiving Ok,
it identifies the highest id node and, generates a
Coordinator message to be updated about the newer
coordinator node, and sends to all the nodes of both sets.
If the node detects itself as the next highest node just
after the crashed node, it declares itself as a leader node.
ii. Candidate failure Case (CFC): If the failure detector
doesn’t get any reply from any candidate within the
given time duration then it is assumed that all candidate
nodes have been crashed, and starts election of the
ordinary node set. But this case is rare as it is not
possible that in the network 50% nodes get crashed.
iii. Electioneer Failure Case (EFC): This case arises when
the electioneer node gets failed just after sending election
messages to other nodes, so the candidate node waits till
(Tok, i) time. If the Potential candidate node doesn’t get
coordinator message within (Tok, i) time it will announce
itself as a coordinator.
iv. Simultaneous election Case (SEC): Here more than one
electioneer node starts election; simultaneously potential
node that gets election message sends an ok message
only to the highest id sender node. So the highest id
detector node declares the new leader node by
broadcasting the coordinator message.
v. Node Revival Case (NRC): This case arises when a
crashed node recovers from failure. If the recovered node
is an ordinary node then it sends a query message to the
nodes of candidate set and if it is a candidate node then it
sends the query message to the just higher id node of its
own set. Then the nodes which receive the query
message send the answer message that contains the id of
the current leader node and the ids of the members of the
candidate node.
This algorithm requires 2N-1 messages in the worst case if at least one
candidate node exists. When the case NRC arises, it takes N-1
messages. This algorithm also gives better solution towards
simultaneous election of the leader node, where number of messages
are minimized by the use of tiebreaker time and set division process.
This algorithm ensures aliveness and safety requirements of the leader
election algorithm. The algorithm claims to be fast, correct and
efficient, and also requires fewer numbers of messages to elect a new
leader. As it is said that the total nodes will be divided into two sets,
the sets are required to be arranged in ascending order or descending
order. Whenever any crashed node recovers, it is required to arrange
the group every time. It gives a complex structure due to various
technical complexities in the calculation of tiebreaker time δ other
mathematical terms [5].
The other approach for election algorithm is the use of exact two
successors with main coordinator node. It is also called Vice
Coordinator Election algorithm. Here the author has provided the
concept of defining the two successor nodes before starting any process.
So, whenever the main coordinator will be crashed, the 1st
successor
will be decided as the next main leader, which will minimize the
number of messages passing for the election of the next main
coordinator. It rarely happens that both successor and main coordinator
get crashed simultaneously. So, in this the process, the highest id node
is elected as the main coordinator and then this main coordinator sends
3. Journal of Advanced Computing and Communication Technologies (ISSN: 2347 - 2804)
Volume No.3 Issue No. 2, April 2015
42
two messages to the next two highest id processors to define the main
successor and sub successor.
Two types of messages are used here-- one is coordinator message, and
the other is election message. The coordinator message is the message
that is sent by the coordinator to the two main successors to inform
them that they are the successors. Also the nodes check that the
successors are in the active state. The successor nodes send an
acknowledgment message to ensure their availability. After this
confirmation, the coordinator node sends n-3 messages to the rest of the
nodes to inform the successor ids. When the main coordinator gets
crashed, then the election message comes in the role, as the election
message is sent by the node which detects the failure of the coordinator
node to the main successor. Then the main successor checks whether
the main coordinator is alive or actually dead. If it is dead, then it sends
n-2 new coordinator messages to all other nodes. Here there are n-2
messages because coordinator information has to be sent to all except
the dead coordinator and the successor itself. After that, the main
successor selects its next two successors by an additional message, as
for this the first has already been defined. So, the total time required
here is n-2+1. According to the process and required number of
messages, the time complexity is derived as O (n). According to
algorithm whenever the coordinator fails, it will elect the new successor
that gives an extra overhead of election of successors, and in the worst
case if both successors fail, then it will move to the traditional election
algorithm approach. Also, it doesn’t provide any solution to the
simultaneous election of coordinator failure detector [6].
Another approach is the concept of Heap Tree. This puts great effort in
reducing the number of messages passing for the election of the
coordinator. Here the concept of the election of coordinator is based on
heap tree, as the set of nodes are structured as a heap tree of nodes. As
the principle of election algorithm says the highest id node is selected as
the leader, so in heap tree the MAX HEAP is used, because the max
heap tree contains the highest id node at the root of the tree that gives an
easier way to get the ids in a hierarchy with fewer comparisons. Here
MAX-HEAPIFY () procedure is used to generate the max heap, which
run in the complexity of O (log (n)). In max heap, the father node is
always greater than their children, but children don’t have any fixed
sequence as the left sibling can be greater than the right and vice-versa.
So there is an improvement proposed to maintain the sequence, where
algorithm requires only one comparison, and we can decide which child
node has the larger value. Now whenever any node gets the information
that the leader has crashed (the root has been deleted), and the node
sends the election message to its father, the message is traversed until it
reaches to the child of root node. When the children of the root receive
the message they don’t need to do more comparisons as it is pre-decided
that the left child has greater value than the right child. So the left child
is immediately designated as the new leader. By this, the number of
messages in the election of the coordinator can be optimized, as there is
no need to send the election message to all the nodes in the tree. In the
above approach, the leader can be decided in less than O (log n) time.
But here each node has to maintain the information of its father, the left
child, the right child and its sibling, which requires the same memory
space as 4n, as much as the heap tree needs. When each node sends the
maximum number of messages to its parents, then also n-1 messages
will be sent at the most. So in the max heap method, maximum number
of messages can be passed in the order of (n-1). Here the main issue is
that whenever the root is deleted, each time the MAX-HEAPIFY ()
procedure is required to build the heap [7].
Here, the other approach over the max heap is the use of Fibonacci heap
used to maintain the structure of nodes to get the new leader fast. The
concept of Fibonacci heap says that it is better than max heap in the
process based on time complexity and number of comparisons. In
Fibonacci heap the procedures for creation of heap, insertion of node,
finding minimum, decreasing root, union of heaps take O(1) time and
deletion of min key takes O(log n) amortized time. The maximum
degree achieved using Fibonacci heap is O (log n) and the maximum
number of messages required to pass is in the order of O (log n) [8].
4. COMPARISON AND DISCUSSION
By the comparison of above various election algorithms, we got the
information about the different concepts used in each and every
algorithm. The comparison also defines the series of algorithms with the
better approach. The efficiency of the algorithm is justified by the
comparison of the number of messages that are required in the selection
of the new leader node. It also gets confirmed by the comparison of
time complexity of above-mentioned algorithms. By the comparison of
above five to six algorithms, the first bully algorithm proposed by
Garcia-Molina is proved as the simplest algorithm but not efficient as it
requires heavy number of messages passing with the time complexity of
O (n2
). As there are so many parameters to prove an algorithm efficient,
the election algorithm with Fibonacci heap structure gives the time
complexity of O(log n) and takes smaller memory space in comparison
to other election algorithms.
The comparison of above defined algorithm is given in the table form
that shows the comparison of the order of message passing.
Table1: Performance of Algorithm of Leader Election
Algorithm Memory
Required
Order Minimum
Message
Fibonacci Heap 4n log(n) log (n)
Modified max heap 4n log(n) log(n)
Bully with Two Successor n2
n n-2
Enhanced Bully n2
n n-1
Modified Election n2
n (n-2)+1
Modified Bully n2
n n-1
Bully n2
n2
2n-2
5. CONCLUSION AND FUTURE WORK
In this paper, we presented a comparison of various election algorithms
to get the idea about one of all the efficient algorithms mentioned here.
It is the election algorithm with Fibonacci heap structure with the time
complexity of O(log n). In future, we will try to implement the election
algorithm on the binomial heap. This would be better than the Fibonacci
heap in terms of processing and time complexity.
4. Journal of Advanced Computing and Communication Technologies (ISSN: 2347 - 2804)
Volume No.3 Issue No. 2, April 2015
43
REFERENCES
[1] Sinha, P.K. Distributed Operating Systems Concepts and
Design; Prentice-Hall: Upper SaddleRiver, NJ, USA, 2002;
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[2] Garcia-Molina, H. Elections in a distributed computing
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[3] Mamun, Q.E.K.; Masum, S.M.; Mustafa, M.A.R. Modified
Bully Algorithm for Electing Coordinator in Distributed
Systems. In Proceedings of the 3rd WSEAS International
Conference on Software Engineering, Parallel and Distributed
Systems, Salzburg, Austria, 13–15 February 2004.
[4] Gholipour, M.; Kordafshari, M.; Jahanshahi, M.; ahmani, A.
A New Approach for Election Algorithm in Distributed
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Quality of Service, Colmar, France, 20–25 July 2009; pp. 70–
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[5] Md. Golam Murshed, Alastair R. Allen*; Enhanced Bully
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computers 1010003
[6] B. alhadidi, L. H. baniata, M. H. baniata, M. Al-sharaiah;
Reducing Message passing and Time Complexity in Bully
Election Algorithms using Two Successors, IJEEE,2013
[7] Yadav, D.K.;Lamba, C.S.;Shukla, S.; A New Approach of
leader Election in Distributed System, Sixth International
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[8] Jain, A.K.; Sharma, R.; Leader Election Algorithm in
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[9] Tanenbaum, A.S.; Steen, M.V. Distributed Systems Principles
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