This paper discusses an imperfect preventive maintenance model for a deteriorating repairable system with
consideration of the reliability limitand random maintenance quality. The model is derived from the
combination of failure rate adjustment and age over an infinite time horizon. The maintenance intervals are
obtained assuming both the failure rate increase factor and age restoration factor are random variables with a
uniform distribution. The optimal policy with a sensitivity analysis showing how different cost parameters affect
the long run average maintenance cost rate is presented.
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.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
A tricky task scheduling technique to optimize time cost and reliability in m...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Task scheduling methodologies for high speed computing systemsijesajournal
High Speed computing meets ever increasing real-time computational demands through the leveraging of
flexibility and parallelism. The flexibility is achieved when computing platform designed with
heterogeneous resources to support multifarious tasks of an application where as task scheduling brings
parallel processing. The efficient task scheduling is critical to obtain optimized performance in
heterogeneous computing Systems (HCS). In this paper, we brought a review of various application
scheduling models which provide parallelism for homogeneous and heterogeneous computing systems. In
this paper, we made a review of various scheduling methodologies targeted to high speed computing
systems and also prepared summary chart. The comparative study of scheduling methodologies for high
speed computing systems has been carried out based on the attributes of platform & application as well.
The attributes are execution time, nature of task, task handling capability, type of host & computing
platform. Finally a summary chart has been prepared and it demonstrates that the need of developing
scheduling methodologies for Heterogeneous Reconfigurable Computing Systems (HRCS) which is an
emerging high speed computing platform for real time applications.
Cluster Computing Environment for On - line Static Security Assessment of lar...IDES Editor
The increased size of modern power systems
demand faster and accurate means for the security assessment,
so that the decisions for reliable and secure operation planning
could be drawn in a systematic manner. Large computational
overhead is the major impediment in preventing the power
system security assessment (PSSA) from on-line use. To
mitigate this problem, this paper proposes, a cluster computing
based architecture for power system static security assessment,
utilizing the tools in the open source domain. A variant of the
master/slave pattern is used for deploying the cluster of
workstations (COW), which act as the computational engine
for the on-line PSSA. The security assessment is performed
utilizing the developed composite security index that can
accurately differentiate the secure and non-secure cases and
has been defined as a function of bus voltage and line flow
limit violations. Due to the inherent parallel structure of
security assessment algorithm and to exploit the potential of
distributed computing, domain decomposition is employed for
parallelizing the sequential algorithm. Extensive
experimentations were carried out on IEEE 57 bus and IEEE
145-bus 50 machine standard test systems for demonstrating
the validity of the proposed architecture.
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.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
A tricky task scheduling technique to optimize time cost and reliability in m...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Task scheduling methodologies for high speed computing systemsijesajournal
High Speed computing meets ever increasing real-time computational demands through the leveraging of
flexibility and parallelism. The flexibility is achieved when computing platform designed with
heterogeneous resources to support multifarious tasks of an application where as task scheduling brings
parallel processing. The efficient task scheduling is critical to obtain optimized performance in
heterogeneous computing Systems (HCS). In this paper, we brought a review of various application
scheduling models which provide parallelism for homogeneous and heterogeneous computing systems. In
this paper, we made a review of various scheduling methodologies targeted to high speed computing
systems and also prepared summary chart. The comparative study of scheduling methodologies for high
speed computing systems has been carried out based on the attributes of platform & application as well.
The attributes are execution time, nature of task, task handling capability, type of host & computing
platform. Finally a summary chart has been prepared and it demonstrates that the need of developing
scheduling methodologies for Heterogeneous Reconfigurable Computing Systems (HRCS) which is an
emerging high speed computing platform for real time applications.
Cluster Computing Environment for On - line Static Security Assessment of lar...IDES Editor
The increased size of modern power systems
demand faster and accurate means for the security assessment,
so that the decisions for reliable and secure operation planning
could be drawn in a systematic manner. Large computational
overhead is the major impediment in preventing the power
system security assessment (PSSA) from on-line use. To
mitigate this problem, this paper proposes, a cluster computing
based architecture for power system static security assessment,
utilizing the tools in the open source domain. A variant of the
master/slave pattern is used for deploying the cluster of
workstations (COW), which act as the computational engine
for the on-line PSSA. The security assessment is performed
utilizing the developed composite security index that can
accurately differentiate the secure and non-secure cases and
has been defined as a function of bus voltage and line flow
limit violations. Due to the inherent parallel structure of
security assessment algorithm and to exploit the potential of
distributed computing, domain decomposition is employed for
parallelizing the sequential algorithm. Extensive
experimentations were carried out on IEEE 57 bus and IEEE
145-bus 50 machine standard test systems for demonstrating
the validity of the proposed architecture.
Fault-Tolerance Aware Multi Objective Scheduling Algorithm for Task Schedulin...csandit
Computational Grid (CG) creates a large heterogeneous and distributed paradigm to manage and execute the applications which are computationally intensive. In grid scheduling tasks are assigned to the proper processors in the grid system to for its execution by considering the execution policy and the optimization objectives. In this paper, makespan and the faulttolerance of the computational nodes of the grid which are the two important parameters for the task execution, are considered and tried to optimize it. As the grid scheduling is considered to be NP-Hard, so a meta-heuristics evolutionary based techniques are often used to find a solution for this. We have proposed a NSGA II for this purpose. The performance estimation ofthe proposed Fault tolerance Aware NSGA II (FTNSGA II) has been done by writing program in Matlab. The simulation results evaluates the performance of the all proposed algorithm and the results of proposed model is compared with existing model Min-Min and Max-Min algorithm which proves effectiveness of the model.
Reinforcement learning based multi core scheduling (RLBMCS) for real time sys...IJECEIAES
Embedded systems with multi core processors are increasingly popular because of the diversity of applications that can be run on it. In this work, a reinforcement learning based scheduling method is proposed to handle the real time tasks in multi core systems with effective CPU usage and lower response time. The priority of the tasks is varied dynamically to ensure fairness with reinforcement learning based priority assignment and Multi Core MultiLevel Feedback queue (MCMLFQ) to manage the task execution in multi core system
ANALYSIS OF THRESHOLD BASED CENTRALIZED LOAD BALANCING POLICY FOR HETEROGENEO...ijait
Heterogeneous machines can be significantly better than homogeneous machines but for that an effective workload distribution policy is required. Maximum realization of the performance can be achieved when system designer will overcome load imbalance condition within the system. Load
distribution and load balancing policy together can reduce total execution time and increase system throughput.
In this paper; we provide algorithm analysis of a threshold based job allocation and load balancing policy for heterogeneous system where all incoming jobs are judiciously and transparently distributed among sharing nodes on the basis of jobs’ requirement and processor capability for the maximization of performance and decline in execution time. A brief discussion of job allocation, transfer and location policy is given with explanation of how load imbalance condition is solved within the system. A flow of scheme is given with essential code and analysis of present algorithm is given to show how this algorithm is better.
An Implementation on Effective Robot Mission under Critical Environemental Co...IJERA Editor
Software engineering is a field of engineering, for designing and writing programs for computers or other electronic devices. A software engineer, or programmer, writes software (or changes existing software) and compiles software using methods that make it better quality. Is the application of engineering to the design, development, implementation, testingand main tenance of software in a systematic method. Now a days the robotics are also plays an important role in present automation concepts. But we have several challenges in that robots when they are operated in some critical environments. Motion planning and task planning are two fundamental problems in robotics that have been addressed from different perspectives. For resolve this there are Temporal logic based approaches that automatically generate controllers have been shown to be useful for mission level planning of motion, surveillance and navigation, among others. These approaches critically rely on the validity of the environment models used for synthesis. Yet simplifying assumptions are inevitable to reduce complexity and provide mission-level guarantees; no plan can guarantee results in a model of a world in which everything can go wrong. In this paper, we show how our approach, which reduces reliance on a single model by introducing a stack of models, can endow systems with incremental guarantees based on increasingly strengthened assumptions, supporting graceful degradation when the environment does not behave as expected, and progressive enhancement when it does.
A developer needs to evaluate software performance metrics such as power consumption at an early stage of design phase to make a device or a software efficient especially in real-time embedded systems. Constructing performance models and evaluation techniques of a given system requires a significant effort. This paper presents a framework to bridge between a Functional Modeling Approach such as FSM, UML etc. and an Analytical (Mathematical) Modeling Approach such as Hierarchical Performance Modeling (HPM) as a technique to find the expected average power consumption for different layers of abstractions. A Hierarchical Generic FSM “HGFSM” is developed to be used in order to estimate the expected average power. A case study is presented to illustrate the concepts of how the framework is used to estimate the average power and energy produced.
Achieving Energy Proportionality In Server ClustersCSCJournals
a great amount of interests in the past few years. Energy proportionality is a principal to ensure that energy consumption is proportional to the system workload. Energy proportional design can effectively improve energy efficiency of computing systems. In this paper, an energy proportional model is proposed based on queuing theory and service differentiation in server clusters, which can provide controllable and predictable quantitative control over power consumption with theoretically guaranteed service performance. Futher study for the transition overhead is carried out corresponding strategy is proposed to compensate the performance degradation caused by transition overhead. The model is evaluated via extensive simulations and is justified by the real workload data trace. The results show that our model can achieve satisfied service performance while still preserving energy efficiency in the system.
Multilevel Hybrid Cognitive Load Balancing Algorithm for Private/Public Cloud...IDES Editor
Cloud computing is an emerging computing
paradigm. It aims to share data, resources and services
transparently among users of a massive grid. Although the
industry has started selling cloud-computing products,
research challenges in various areas, such as architectural
design, task decomposition, task distribution, load
distribution, load scheduling, task coordination, etc. are still
unclear. Therefore, we study the methods to reason and model
cloud computing as a step towards identifying fundamental
research questions in this paradigm. In this paper, we propose
a model for load distribution on cloud computing by modeling
them as cognitive systems and using aspects which not only
depend on the present state of the system, but also, on a set of
predefined transitions and conditions. The entirety of this
model is then bundled to cater the task of job distribution
using the concept of application metadata. Later, we draw a
qualitative and simulation based summarization for the
proposed model. We finally evaluate the results and draw up
a series of key conclusions in cloud computing for future
exploration.
The problem of controlling an unstable delayed double integrating process with fractional delay using a
feed forward first-order lag-lead compensator is studied. The effect of time delay of the process in a range between
0.1 and 0.9 seconds is considered. The compensator is tuned using MATLAB optimization toolbox with five forms
of the objective function in terms of the error between the step time response of the closed-loop control system and
the response steady-state value. Using the proposed compensator with the fractional delayed double integrating
process indicates the robustness of the compensator in the time delay range used with superior time-based
specifications compared with other technique based on PID controller.
Keywords — Delayed double integrating process with fractional delay, Feed forward lag-lead first-order
compensator, compensator tuning, MATLAB optimization toolbox, Control system performance.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Parameter Estimation of Software Reliability Growth Models Using Simulated An...Editor IJCATR
The parameter estimation of Goel’s Okomotu Model is performed victimisation simulated annealing. The Goel’s Okomotu
Model is predicated on Exponential model and could be a easy non-homogeneous Poisson method (NHPP) model. Simulated
annealing could be a heuristic optimisation technique that provides a method to flee local optima. The information set is optimized
using simulated annealing technique. SA could be a random algorithmic program with higher performance than Genetic algorithmic
program (GA) that depends on the specification of the neighbourhood structure of a state area and parameter settings for its cooling
schedule.
ESTIMATING HANDLING TIME OF SOFTWARE DEFECTScsandit
The problem of accurately predicting handling time for software defects is of great practical
importance. However, it is difficult to suggest a practical generic algorithm for such estimates,
due in part to the limited information available when opening a defect and the lack of a uniform
standard for defect structure. We suggest an algorithm to address these challenges that is
implementable over different defect management tools. Our algorithm uses machine learning
regression techniques to predict the handling time of defects based on past behaviour of similar
defects. The algorithm relies only on a minimal set of assumptions about the structure of the
input data. We show how an implementation of this algorithm predicts defect handling time with
promising accuracy results
Design and Implementation of Proportional Integral Observer based Linear Mode...IDES Editor
This paper presents an interior-point method (IPM)
based quadratic programming (QP) solver for the solution of
optimal control problem in linear model predictive control
(MPC). LU factorization is used to solve the system of linear
equations efficiently at each iteration of IPM, which renders
faster execution of QP solver. The controller requires internal
states of the system. To address this issue, a Proportional
Integral Observer (PIO) is designed, which estimates the state
vector, as well as the uncertainties in an integrated manner.
MPC uses the states estimated by PIO, and the effect of
uncertainty is compensated by augmenting MPC with PIOestimated
uncertainties and external disturbances. The
approach is demonstrated practically by applying MPC to QET
DC servomotor for position control application. The proposed
method is compared with classical control strategy-PID
control.
EFFICIENT SCHEDULING STRATEGY USING COMMUNICATION AWARE SCHEDULING FOR PARALL...ijdpsjournal
In the area of Computer Science, Parallel job scheduling is an important field of research. Finding a best
suitable processor on the high performance or cluster computing for user submitted jobs plays an
important role in measuring system performance. A new scheduling technique called communication aware
scheduling is devised and is capable of handling serial jobs, parallel jobs, mixed jobs and dynamic jobs.
This work focuses the comparison of communication aware scheduling with the available parallel job
scheduling techniques and the experimental results show that communication aware scheduling performs
better when compared to the available parallel job scheduling techniques.
Fault tolerance is an important issue in the field of cloud computing which is concerned with the techniques or mechanism needed to enable a system to tolerate the faults that may encounter during its functioning. Fault tolerance policy can be categorized into three categories viz. proactive, reactive and adaptive. Providing a systematic solution the loss can be minimized and guarantee the availability and reliability of the critical services. The purpose and scope of this study is to recommend Support Vector Machine, a supervised machine learning algorithm to proactively monitor the fault so as to increase the availability and reliability by combining the strength of machine learning algorithm with cloud computing.
Performance Analysis of TCP and SCTP For Congestion Losses In ManetIJERA Editor
Transmission control protocols have been used for data transmission process. TCP has been pre-owned for data transmission over wired communication having different bandwidths and message delays over the network. TCP provides communication using 3-handshake which sends RTS and ACK comes from server end and data message has been transmitted over the bandwidth provided. This does not provide security over flooding attack occurred on the network. TCP provides communication between different nodes of the wired communication but when multi-streaming occurs in a network TCP does not provides proper throughput of the system which is major problem that occurred in the previous system. In the proposed work, to overcome this problem SCTP transmission control protocol has been implemented for the system performance of the system. SCTP provides 4-handshake communication in the message transmit due to which security factor get increases and this also provides communication services over multi-streaming and multi-homing. Multiple sender and receivers can communicate over wired network using various approaches of communication through same routers, which degrades in the TCP protocol. In final we evaluate parameters for performance evaluation. Here, we designed and implemented our test bed using Network Simulator (NS-2.35) to test the performance of both Routing protocols.
Modified Sierpinski Gasket for Wi-Fi and WLAN ApplicationsIJERA Editor
The hasty growth of wireless technologies has drawn new demands for integrated components including antennas and antenna on chip is a new mantra in the area of antenna research. Various techniques have been suggested by researchers for the miniaturization of microstrip patch antennas with multiband characteristics. Numerous antennas for multiband operation have been studied and designed for communication and radar systems. One of the solutions for the multiband characteristics is the fractal antenna. The Fractal antennas are based on the concept of fractal geometries. They can be designed in a variety of shapes in order to obtain enhanced gain and bandwidth, dual band and circular polarization to even ultra-wideband operation. In this paper, the fractal antenna has been designed using the Arlon substrate with relative permittivity of 1.3 and a substrate of Sierpinski gasket shaped placed on it. Feed used is the line feed. The designed antenna is a low profile, small size and multiband antenna since it can be operated at different frequencies within the frequency range of (1.75 – 2.65) and (5.7 – 7.65) GHz. It includes the frequencies used for wireless WLAN application and used to receive and transmit a high-frequency signal.
Fault-Tolerance Aware Multi Objective Scheduling Algorithm for Task Schedulin...csandit
Computational Grid (CG) creates a large heterogeneous and distributed paradigm to manage and execute the applications which are computationally intensive. In grid scheduling tasks are assigned to the proper processors in the grid system to for its execution by considering the execution policy and the optimization objectives. In this paper, makespan and the faulttolerance of the computational nodes of the grid which are the two important parameters for the task execution, are considered and tried to optimize it. As the grid scheduling is considered to be NP-Hard, so a meta-heuristics evolutionary based techniques are often used to find a solution for this. We have proposed a NSGA II for this purpose. The performance estimation ofthe proposed Fault tolerance Aware NSGA II (FTNSGA II) has been done by writing program in Matlab. The simulation results evaluates the performance of the all proposed algorithm and the results of proposed model is compared with existing model Min-Min and Max-Min algorithm which proves effectiveness of the model.
Reinforcement learning based multi core scheduling (RLBMCS) for real time sys...IJECEIAES
Embedded systems with multi core processors are increasingly popular because of the diversity of applications that can be run on it. In this work, a reinforcement learning based scheduling method is proposed to handle the real time tasks in multi core systems with effective CPU usage and lower response time. The priority of the tasks is varied dynamically to ensure fairness with reinforcement learning based priority assignment and Multi Core MultiLevel Feedback queue (MCMLFQ) to manage the task execution in multi core system
ANALYSIS OF THRESHOLD BASED CENTRALIZED LOAD BALANCING POLICY FOR HETEROGENEO...ijait
Heterogeneous machines can be significantly better than homogeneous machines but for that an effective workload distribution policy is required. Maximum realization of the performance can be achieved when system designer will overcome load imbalance condition within the system. Load
distribution and load balancing policy together can reduce total execution time and increase system throughput.
In this paper; we provide algorithm analysis of a threshold based job allocation and load balancing policy for heterogeneous system where all incoming jobs are judiciously and transparently distributed among sharing nodes on the basis of jobs’ requirement and processor capability for the maximization of performance and decline in execution time. A brief discussion of job allocation, transfer and location policy is given with explanation of how load imbalance condition is solved within the system. A flow of scheme is given with essential code and analysis of present algorithm is given to show how this algorithm is better.
An Implementation on Effective Robot Mission under Critical Environemental Co...IJERA Editor
Software engineering is a field of engineering, for designing and writing programs for computers or other electronic devices. A software engineer, or programmer, writes software (or changes existing software) and compiles software using methods that make it better quality. Is the application of engineering to the design, development, implementation, testingand main tenance of software in a systematic method. Now a days the robotics are also plays an important role in present automation concepts. But we have several challenges in that robots when they are operated in some critical environments. Motion planning and task planning are two fundamental problems in robotics that have been addressed from different perspectives. For resolve this there are Temporal logic based approaches that automatically generate controllers have been shown to be useful for mission level planning of motion, surveillance and navigation, among others. These approaches critically rely on the validity of the environment models used for synthesis. Yet simplifying assumptions are inevitable to reduce complexity and provide mission-level guarantees; no plan can guarantee results in a model of a world in which everything can go wrong. In this paper, we show how our approach, which reduces reliance on a single model by introducing a stack of models, can endow systems with incremental guarantees based on increasingly strengthened assumptions, supporting graceful degradation when the environment does not behave as expected, and progressive enhancement when it does.
A developer needs to evaluate software performance metrics such as power consumption at an early stage of design phase to make a device or a software efficient especially in real-time embedded systems. Constructing performance models and evaluation techniques of a given system requires a significant effort. This paper presents a framework to bridge between a Functional Modeling Approach such as FSM, UML etc. and an Analytical (Mathematical) Modeling Approach such as Hierarchical Performance Modeling (HPM) as a technique to find the expected average power consumption for different layers of abstractions. A Hierarchical Generic FSM “HGFSM” is developed to be used in order to estimate the expected average power. A case study is presented to illustrate the concepts of how the framework is used to estimate the average power and energy produced.
Achieving Energy Proportionality In Server ClustersCSCJournals
a great amount of interests in the past few years. Energy proportionality is a principal to ensure that energy consumption is proportional to the system workload. Energy proportional design can effectively improve energy efficiency of computing systems. In this paper, an energy proportional model is proposed based on queuing theory and service differentiation in server clusters, which can provide controllable and predictable quantitative control over power consumption with theoretically guaranteed service performance. Futher study for the transition overhead is carried out corresponding strategy is proposed to compensate the performance degradation caused by transition overhead. The model is evaluated via extensive simulations and is justified by the real workload data trace. The results show that our model can achieve satisfied service performance while still preserving energy efficiency in the system.
Multilevel Hybrid Cognitive Load Balancing Algorithm for Private/Public Cloud...IDES Editor
Cloud computing is an emerging computing
paradigm. It aims to share data, resources and services
transparently among users of a massive grid. Although the
industry has started selling cloud-computing products,
research challenges in various areas, such as architectural
design, task decomposition, task distribution, load
distribution, load scheduling, task coordination, etc. are still
unclear. Therefore, we study the methods to reason and model
cloud computing as a step towards identifying fundamental
research questions in this paradigm. In this paper, we propose
a model for load distribution on cloud computing by modeling
them as cognitive systems and using aspects which not only
depend on the present state of the system, but also, on a set of
predefined transitions and conditions. The entirety of this
model is then bundled to cater the task of job distribution
using the concept of application metadata. Later, we draw a
qualitative and simulation based summarization for the
proposed model. We finally evaluate the results and draw up
a series of key conclusions in cloud computing for future
exploration.
The problem of controlling an unstable delayed double integrating process with fractional delay using a
feed forward first-order lag-lead compensator is studied. The effect of time delay of the process in a range between
0.1 and 0.9 seconds is considered. The compensator is tuned using MATLAB optimization toolbox with five forms
of the objective function in terms of the error between the step time response of the closed-loop control system and
the response steady-state value. Using the proposed compensator with the fractional delayed double integrating
process indicates the robustness of the compensator in the time delay range used with superior time-based
specifications compared with other technique based on PID controller.
Keywords — Delayed double integrating process with fractional delay, Feed forward lag-lead first-order
compensator, compensator tuning, MATLAB optimization toolbox, Control system performance.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Parameter Estimation of Software Reliability Growth Models Using Simulated An...Editor IJCATR
The parameter estimation of Goel’s Okomotu Model is performed victimisation simulated annealing. The Goel’s Okomotu
Model is predicated on Exponential model and could be a easy non-homogeneous Poisson method (NHPP) model. Simulated
annealing could be a heuristic optimisation technique that provides a method to flee local optima. The information set is optimized
using simulated annealing technique. SA could be a random algorithmic program with higher performance than Genetic algorithmic
program (GA) that depends on the specification of the neighbourhood structure of a state area and parameter settings for its cooling
schedule.
ESTIMATING HANDLING TIME OF SOFTWARE DEFECTScsandit
The problem of accurately predicting handling time for software defects is of great practical
importance. However, it is difficult to suggest a practical generic algorithm for such estimates,
due in part to the limited information available when opening a defect and the lack of a uniform
standard for defect structure. We suggest an algorithm to address these challenges that is
implementable over different defect management tools. Our algorithm uses machine learning
regression techniques to predict the handling time of defects based on past behaviour of similar
defects. The algorithm relies only on a minimal set of assumptions about the structure of the
input data. We show how an implementation of this algorithm predicts defect handling time with
promising accuracy results
Design and Implementation of Proportional Integral Observer based Linear Mode...IDES Editor
This paper presents an interior-point method (IPM)
based quadratic programming (QP) solver for the solution of
optimal control problem in linear model predictive control
(MPC). LU factorization is used to solve the system of linear
equations efficiently at each iteration of IPM, which renders
faster execution of QP solver. The controller requires internal
states of the system. To address this issue, a Proportional
Integral Observer (PIO) is designed, which estimates the state
vector, as well as the uncertainties in an integrated manner.
MPC uses the states estimated by PIO, and the effect of
uncertainty is compensated by augmenting MPC with PIOestimated
uncertainties and external disturbances. The
approach is demonstrated practically by applying MPC to QET
DC servomotor for position control application. The proposed
method is compared with classical control strategy-PID
control.
EFFICIENT SCHEDULING STRATEGY USING COMMUNICATION AWARE SCHEDULING FOR PARALL...ijdpsjournal
In the area of Computer Science, Parallel job scheduling is an important field of research. Finding a best
suitable processor on the high performance or cluster computing for user submitted jobs plays an
important role in measuring system performance. A new scheduling technique called communication aware
scheduling is devised and is capable of handling serial jobs, parallel jobs, mixed jobs and dynamic jobs.
This work focuses the comparison of communication aware scheduling with the available parallel job
scheduling techniques and the experimental results show that communication aware scheduling performs
better when compared to the available parallel job scheduling techniques.
Fault tolerance is an important issue in the field of cloud computing which is concerned with the techniques or mechanism needed to enable a system to tolerate the faults that may encounter during its functioning. Fault tolerance policy can be categorized into three categories viz. proactive, reactive and adaptive. Providing a systematic solution the loss can be minimized and guarantee the availability and reliability of the critical services. The purpose and scope of this study is to recommend Support Vector Machine, a supervised machine learning algorithm to proactively monitor the fault so as to increase the availability and reliability by combining the strength of machine learning algorithm with cloud computing.
Performance Analysis of TCP and SCTP For Congestion Losses In ManetIJERA Editor
Transmission control protocols have been used for data transmission process. TCP has been pre-owned for data transmission over wired communication having different bandwidths and message delays over the network. TCP provides communication using 3-handshake which sends RTS and ACK comes from server end and data message has been transmitted over the bandwidth provided. This does not provide security over flooding attack occurred on the network. TCP provides communication between different nodes of the wired communication but when multi-streaming occurs in a network TCP does not provides proper throughput of the system which is major problem that occurred in the previous system. In the proposed work, to overcome this problem SCTP transmission control protocol has been implemented for the system performance of the system. SCTP provides 4-handshake communication in the message transmit due to which security factor get increases and this also provides communication services over multi-streaming and multi-homing. Multiple sender and receivers can communicate over wired network using various approaches of communication through same routers, which degrades in the TCP protocol. In final we evaluate parameters for performance evaluation. Here, we designed and implemented our test bed using Network Simulator (NS-2.35) to test the performance of both Routing protocols.
Modified Sierpinski Gasket for Wi-Fi and WLAN ApplicationsIJERA Editor
The hasty growth of wireless technologies has drawn new demands for integrated components including antennas and antenna on chip is a new mantra in the area of antenna research. Various techniques have been suggested by researchers for the miniaturization of microstrip patch antennas with multiband characteristics. Numerous antennas for multiband operation have been studied and designed for communication and radar systems. One of the solutions for the multiband characteristics is the fractal antenna. The Fractal antennas are based on the concept of fractal geometries. They can be designed in a variety of shapes in order to obtain enhanced gain and bandwidth, dual band and circular polarization to even ultra-wideband operation. In this paper, the fractal antenna has been designed using the Arlon substrate with relative permittivity of 1.3 and a substrate of Sierpinski gasket shaped placed on it. Feed used is the line feed. The designed antenna is a low profile, small size and multiband antenna since it can be operated at different frequencies within the frequency range of (1.75 – 2.65) and (5.7 – 7.65) GHz. It includes the frequencies used for wireless WLAN application and used to receive and transmit a high-frequency signal.
Intellectual Bank Locker Security SystemIJERA Editor
In today's modern world, security plays an important role. Every person has precious accessories like gold,
documents or cash. The main goal of this project is to design and implement a bank locker security system
based on fingerprint and GSM technology. It reduces wastage of time for both banker as well as customer and
provides advanced security. In this system, only authentic persons can recover money or accessories from bank
locker. In this system the user’s name, fingerprint and mobile number are enrolled. If the fingerprint matches,
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The research and development in the precise and accurate machining technology of hard metals (Ferrous, non-ferrous and glass etc) is gaining much importance in the industry since last many years. Due to the tremendous competition and cost factor, the non-conventional machining technology is becoming the first choice of the engineers and technicians. In this era of advanced technological processes the CNC plasma arc machining is gaining tremendous ground in the industry. It is much more capable of producing best finished, high accurate machining of very complicated non-symmetrical profile in no time. The main objective and targets of this practical experiment is based to achieve the best possible setting and parameters of operation on a CNC plasma arc machine to achieving speedy work i.e. Maximum material removal rate.
Autosizing Control Panel for Needle BearingIJERA Editor
A needle roller bearing is a bearing which uses small cylindrical rollers. Bearings are used to reduce friction of
any rotating surface. Needle bearings have a large surface in contact with the bearing outer surfaces as
compared to ball bearings. There is less added clearance(Diameter of the shaft and the diameter of the bearing
are different) so they are much compact. The structure consists of a needle cage which contains the needle
rollersthemselves and an outer race (The housing itself). Radial bearings are cylindrical and they use rollers
parallel to the axis of the shaft. Radial pattern of needle are being used by thrust needles. Complement bearings
have solid inner as well as outer rings and rib-guided cylindrical rollers. The bearings have the largest number
of rolling elements and also have extremely high radial load carrying capacity and are suitable for compact
designs.Needle roller bearings have relatively small diameter cylindrical rolling elements whose length is much
larger than their diameter. As compared to other types of rolling bearings, needle roller bearings possess a small
cross-sectional height and significant load-bearing capacity and rigidity relative to their volume. Also, because
the inertial force acting on them is limited, needle bearings are an ideal choice for applications with oscillating
motion. These bearings also work well in compact and lightweight machine designs and they serve as a ready
replacement for sliding bearings. Needle bearings features are great rigidity, smaller cross-section, higher loadcarrying
capacity, and has lower inertia forces that facilitate to size and weight reductions in machinery. Needle
bearings are designed to stand in oscillation, performwell under any conditions, and interchange with the sliding
of bearings.
Comparative Study on the Design of Square,Rectangular and Circular Concrete W...IJERA Editor
Reinforced concrete overhead water tanks are used to store and supply safe drinking water. Design and cost estimation of overhead water tanks is a time consuming task, which requires a great deal of expertise. This study therefore examines the efficiency of Rectangular and Circular tanks. Tanks of 30m3, 90m3, 140m3 and 170m3 capacities were used in order to draw reasonable inferences on tank‟s shape design effectiveness, relative cost implications of tank types and structural capacities. Limit state design criteria were used for basic tank‟s construction materials- steel reinforcement, concrete and formwork were taken-off from the prepared structural drawings. Results of the material take-offs showed that, for each of the shapes, the amount of each structural materials increase as the tank capacity increases. Also Circular-shaped tank consumed lesser individual material as compared to Rectangular ones. Hence, this will give Circular-shaped tanks a more favoured selection over the rectangular shaped tanks.
Visible Light Induced Selective Photocatalytic Oxidation of Benzyl Amine to N...IJERA Editor
Irradiated semiconductor catalysis in the presence of molecular oxygen can be considered as an innovative and sustainable technique for organic transformations. The present work reports the preparation ofGraphene oxide/TiO2composite by improved Hummer’s method followed by hydrothermal technique. The prepared system was characterized by various physico-chemical techniques such as X-Ray diffraction, IR-Spectroscopy, UV-DRS, XPS, SEM and TEM Analysis.On reaction, benzylamine in CH3CN yieldedN-benzylidene-1-phenylmethanamine as the sole product. The reaction was monitored by GC-MS Analysis.
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The development of new fibrous composites with specific properties has attracted a big interest in the
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modifications of the rice husk (by-product of the rice industry) were carried out to achieve a better compatibility
with diverse polymeric matrices. These modifications include the use of three different silanes: 3-
(trimethoxysilyl) propyl methacrylate (TMS), dichlorodimethylsilane (DDS) and trichlorovinylsilane (TVS). The
natural fibers and their changes after each treatment were studied experimentally by Fourier Transformed
Infrared Spectroscopy (FTIR). This experimental spectroscopic information was compared with a theoretical
analysis of molecular vibrations using the HyperChem Release 7.0 software as molecular modeling tool. The
result of this comparison confirmed the chemical modification. It was concluded that the chemical modification
was carried out and after an experimental spectroscopic analysis (FTIR) the molecular vibrations data were agree
with those calculated by theoretical analysis being verified in this way the chemical modification of the rice-husk
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Evaluation Of The Level Of Compliance Of Cost Approach To Valuation To Provis...IJERA Editor
The cost approach to Valuation is one of the primary methods of valuation adopted in Nigeria by valuers in
solving industrial valuation problems. The method is based on the principles of contribution and substitution.
Generally, lacks of data, insecurity and instability in the Nigerian economy have made other models relatively,
inapplicable in Nigeria situation. Hence majority of the valuations done in Nigeria adopts the cost approach.
With recent focus of the world on environment, this paper tries to evaluate the level of compliance of this model
to the provisions of the National Environmental Protection (Pollution Abatement in Industries and Facilities
Generating Waste) Regulations of 1991, since Estate Surveyors and Valuers are expected to play their role as
environmental protection advocates. The study adopted the survey research method and data was generated
using an evaluation checklist. The hypothesis developed was tested using the student “t” test and it was
discovered that that Cost approach to valuation does not comply with the provisions of the National
Environmental Protection (Pollution Abatement in Industries and Facilities Generating Waste) Regulation of
1991. The study recommended among other things that the model should be used with caution if Estate
Surveyors and Valuers in Nigeria will continue to play their role as Environmental Protection advocates.
The Effect of Chitosan, Sorbitol, and Heating Temperature Bioplastic Solution...IJERA Editor
Nowadays, bioplastics is often researched to substitute the conventional plastics because bioplastics come from
raw materials that is very enviromentally friendly and bioplastics is degradable. The purposes of this research are
to know the characteristics of starch from durian seed and to know the effect of additional chitosan as filler,
sorbitol as plasticizer, and variation of heating temperature bioplastic solution on mechanical properties of
bioplastics. In process, the ratio between durian-seed starch and chitosan are 7:3, 8:2 and 9:1 gram, while the
concentration of sorbitol are 20%, 30%, and 40%. The heating temperature of bioplastic solution is varied at 70
oC, 80 oC and 90 oC. Result of bioplastic FTIR shows there is increation of wave number N-H from 1570.06 cm-
1 to 1589.34 cm-1 and O-H from 3352.28 cm-1 to 3653.18 cm-1. The characteristic of durian seed starch has water
content 12.73%, ash content 0,51%, starch content 76,65%, amylose content 22.34%, amylopectin content
54.32%, protein content 11.61%, and fat content 0.61%. Optimum mechanical properties of bioplastic from
durian seed starch occurs in heating temperature 70 oC with composition between durian-seed starch and
chitosan is 7:3 grams and sorbitol 20.0 grams.
Study of Measurement of luminescence life time of the Nd3+ ions in the 6-FDA/...IJERA Editor
Luminescence life time measurements of the Nd3+ ions in the 6-FDA/UVR and Al2o3 hosts were performed
using a Laser diode emitting at 800nm as the excitation source. Optical losses in both materials have been
studied and compared absorption bands of Nd3+ have been observed at 580nm ,745nm, 800nm and 870nm .
Based on which Judd- ofelt analysis has been applied to study the transition properties of Nd3+ ions in the two
hosts. Photoluminescence spectra of Nd3+ have been experimentally studied and emission around 880nm,
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Analysis of Stress and Deflection of Cantilever Beam and its Validation Using...IJERA Editor
This study investigates the deflection and stress distribution in a long, slender cantilever beam of uniform
rectangular cross section made of linear elastic material properties that are homogeneous and isotropic. The
deflection of a cantilever beam is essentially a three dimensional problem. An elastic stretching in one direction
is accompanied by a compression in perpendicular directions. The beam is modeled under the action of three
different loading conditions: vertical concentrated
load applied at the free end, uniformly distributed load and uniformly varying load which runs over the whole
span. The weight of the beam is assumed to be negligible. It is also assumed that the beam is inextensible and so
the strains are also negligible. Considering this assumptions at first using the Bernoulli-Euler’s bendingmoment
curvature relationship, the approximate solutions of the cantilever beam was obtained from the general
set of equations. Then assuming a particular set of dimensions, the deflection and stress values of the beam are
calculated analytically. Finite element analysis of the beam was done considering various types of elements
under different loading conditions in ANSYS 14.5. The various numerical results were generated at different
nodal points by taking the origin of the Cartesian coordinate system at the fixed end of the beam. The nodal
solutions were analyzed and compared. On comparing the computational and analytical solutions it was found
that for stresses the 8 node brick element gives the most consistent results and the variation with the analytical
results is minimum.
Online Votes and Fund analysis for political parties with Data SecurityIJERA Editor
With the traditional fund management and vote bank analysis, it was difficult to manage and analyze the details
of fund collection and vote bank where all the records and relevant details were maintained at manual level,
which is always a troublesome process. To overcome these problems, an online web application is being
developed which provide the means of maintaining the funds gathered, Analyzing vote bank generated, Analysis
of area wise grievances and providing data security using encryption algorithms like Advanced Encryption
standard enabling two step verification mechanisms such as legitimate user authentication and secured access to
data. Also various reports will be generated depicting graphical assessment of information gathered.
Assessment of the waste water quality parameter of the Chitrakoot Dham, KarwiIJERA Editor
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than thousand temples in the study area, which are located mainly in Kamadgiri parikrama and along the bank of
river Mandakini. A number of pilgrims visit the place throughout the year. Obviously a considerable amount of
waste generated from the religious activities is being discharged anywhere consequently in creation of sever
solid waste problem.
Assessment of the waste water quality parameter of the Chitrakoot Dham Karwi for the parameters- pH,
Temperature, Nitrate, COD, TDS, TS, TSS, Nitrite, Chloride were analyzed using standard methods prescribed
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Evaluation of Optimal Parameters for Surface Roughness Using Single Objective...IJERA Editor
Medium carbon steel EN8 has a wide variety of applications in oil, gas and tool industries. It is most commonly
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of machining parameters on Surface Roughness (Ra). Taguchi’s single objective optimization technique is used
to optimize the machining parameters in EDM for EN8 steel. For the experimentation Taguchi’s L27
Orthogonal array has been used. The input parameters selected are Pulse on time (PON), Pulse off time (POFF),
Wire tension (WT) and Wire feed (WF). From the Taguchi results, optimal combination of machining
parameters for Surface Roughness is found at Pulse-on time (PON) level 3(131μs), Pulse-off time (POFF) level 2
(58μs), Wire tension (WT) level 1(2 Kg-f) and Wire feed rate (WF) level 1(4m/min). ANOVA was used to find
the influence of machining parameters on Surface Roughness. From the results, it is found that wire feed rate
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Surface Roughness. Regression model for Surface Roughness has been prepared by using MINITAB-16
software. Experimental values and Regression values of Surface Roughness were compared and from the graph,
it is clear that both the values are very close to each other. Hence, Regression model prepared is accurate,
adequate and it can be used for the prediction of Surface Roughness.
Traffic Violation Detection Using Multiple Trajectories of VehiclesIJERA Editor
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management detection using vehicles moving in the region of interest and combining with the evaluation of the
trajectories behavior of multiple vehicles using mean square displacement (MSD) to detected both of violation.
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data using the vertical seismic profiling (VSP) data in Pasir Cantang well, West Java for some layers.
The obtained values of water saturation have not been calibrated to the known value of the well. This step needs
to be done, so that the results that have been corrected can be performed to estimate the area around the well
Pasir Cantang guided by seismic section. Regardless of the calibration factor, the method of the water saturation
estimation on VSP data can technically be well done but still needs necessary calibration for the accuracy.
Plasma-chemical treatment of industrial wastewaters from brewery “Brasseries ...IJERA Editor
This work focuses on the study of the chemical reactivity of an advanced oxidation process (AOP), called the
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application to a target which is a real effluent (wastewater from Brasseries du Cameroun -Bafoussam plant)
fascinated this study. Samples were collected from the central collecting point (CCP) of the effluent. The
collected effluent samples were analyzed by volumetric and instrumental methods, and then exposed to the
gliding discharge during specific time periods of 3-60 min to exhibit the desired decontamination effects. At the
end of 60 min of exposure time to the discharge, 52.22% and 50.19% obtained respectively to abatement of
turbidity and rate of fall in absorbance. This reduction can be explained by the fact that the coloured compounds
were degraded and this degradation gave rise to the transparent appearance observed. After stopping the
discharge process, the abatement percentage of BOD5, COD and TOC, were obtained at the same time (60min)
with values of 52.05%, 68.63% and 69.37% respectively. These results reflect the considerable reduction of the
pollution load of the wastewaters collected from CCP of the brewery. These results showed that the
effectiveness of the gliding arc plasma depends not only on the physico-chemical parameters of the target, but
also on the exposure time and concluded that the non-thermal plasma process alone provides good reduction of
organic pollutants in wastewater. Moreover, the phenomenon of post- discharge, even though not studied in
details demonstrated that, after switching the discharge, the evolution of parameters such as pH, electrical
conductivity and TDS increase.
IMC Based Fractional Order Controller for Three Interacting Tank ProcessTELKOMNIKA JOURNAL
In model based control, performance of the controlled plant considerably depends on the
accuracy of real plant being modelled. In present work, an attempt has been made to design Internal
Model Control (IMC), for three interacting tank process for liquid level control. To avoid complexities in
controller design, the third order three interacting tank process is modelled to First Order Plus Dead Time
(FOPDT) model. Exploiting the admirable features of Fractional Calculus, the higher order model is also
modelled to Fractional Order First Order Plus Dead Time (FO-FOPDT) model, which further reduces the
modelling error. Moving to control section, different IMC schemes have been proposed based on the order
of filter. Various simulations have been performed to show the greatness of Fractional order modelled
system & fractional order filters over conventional integer order modelled system & integer order filters
respectively. Both for parameters estimation of reduced order model and filter tuning, Genetic Algorithm
(GA) is being applied.
MAINTENANCE POLICY AND ITS IMPACT ON THE PERFORMABILITY EVALUATION OF EFT SYS...IJCSEA Journal
In the Electronic Funds Transfer (EFT) Systems, faults can cause severe degradation on the performance of this system. Thus, modelling the performance of EFT system without considering dependability aspects can cause inaccurate results. This paper presents a stochastic model for evaluating performance of processing and storage infrastructures of the EFT system. This work also presents a model for evaluating the effects of the proposed preventive maintenance policy and different service level agreements (SLA) on the dependability of the EFT system infrastructure. Then, this paper combines both models (dependability and performance) for evaluating the impact of dependability issues on the performance of the EFT system. Finally, case studies considering EFT system infrastructures are provided to demonstrate the applicability of the adopted approach. Moreover, the results of these case studies are depicted, stressing important aspects of dependability and performance for EFT system planning.
Monte Carlo simulation convergences’ percentage and position in future relia...IJECEIAES
Reliability assessment is a needed assessment in today's world. It is required not only for system design but also to ensure the power delivered reaches the consumer. It is usual for fault to occur, but it is best if the fault can be predicted and the way to overcome it can be prepared in advance. Monte Carlo simulation is a standard method of assessing reliability since it is a time-based evaluation that nearly represents the actual situation. However, sequential Monte Carlo (SMC) typically took long-time simulation. A convergence element can be implemented into the simulation to ensure that the time taken to compute the simulation can be reduced. The SMC can be done with and without convergence. SMC with convergence has high accuracy compared to the SMC without convergence, as it takes a long time and has a high possibility of not getting accurate output. In this research, the SMC is subjected to five different convergence items to determine which converge simulation is the fastest while providing better performance for reliability evaluation. There are two types of convergence positions, namely input convergence and output convergence. Overall, output convergence shows the best result compared to input convergence.
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Survey on deep learning applied to predictive maintenance IJECEIAES
Prognosis health monitoring (PHM) plays an increasingly important role in the management of machines and manufactured products in today’s industry, and deep learning plays an important part by establishing the optimal predictive maintenance policy. However, traditional learning methods such as unsupervised and supervised learning with standard architectures face numerous problems when exploiting existing data. Therefore, in this essay, we review the significant improvements in deep learning made by researchers over the last 3 years in solving these difficulties. We note that researchers are striving to achieve optimal performance in estimating the remaining useful life (RUL) of machine health by optimizing each step from data to predictive diagnostics. Specifically, we outline the challenges at each level with the type of improvement that has been made, and we feel that this is an opportunity to try to select a state-of-the-art architecture that incorporates these changes so each researcher can compare with his or her model. In addition, post-RUL reasoning and the use of distributed computing with cloud technology is presented, which will potentially improve the classification accuracy in maintenance activities. Deep learning will undoubtedly prove to have a major impact in upgrading companies at the lowest cost in the new industrial revolution, Industry 4.0.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Real-time PMU Data Recovery Application Based on Singular Value DecompositionPower System Operation
Phasor measurement units (PMUs) allow for the enhancement of power system monitoring and control applications and they will prove even more crucial in the future, as the grid becomes more decentralized and subject to higher uncertainty. Tools that improve PMU data quality and facilitate data analytics workflows are thus needed. In this work, we leverage a previously described algorithm to develop a python application for PMU data recovery. Because of its intrinsic nature, PMU data can be dimensionally reduced using singular value decomposition (SVD). Moreover, the high spatio-temporal correlation can be leveraged to estimate the value of measurements that are missing due to drop-outs. These observations are at the base of the data recovery application described in this work. Extensive testing is performed to study the performance under different data drop-out scenarios, and the results show very high recovery accuracy. Additionally, the application is designed to take advantage of a high performance PMU data platform called PredictiveGrid™, developed by PingThings
Real-time PMU Data Recovery Application Based on Singular Value DecompositionPower System Operation
Phasor measurement units (PMUs) allow for the enhancement of power system monitoring and control applications and they will prove even more crucial in the future, as the grid becomes more decentralized and subject to higher uncertainty. Tools that improve PMU data quality and facilitate data analytics workflows are thus needed. In this work, we leverage a previously described algorithm to develop a python application for PMU data recovery. Because of its intrinsic nature, PMU data can be dimensionally reduced using singular value decomposition (SVD). Moreover, the high spatio-temporal correlation can be leveraged to estimate the value of measurements that are missing due to drop-outs. These observations are at the base of the data recovery application described in this work. Extensive testing is performed to study the performance under different data drop-out scenarios, and the results show very high recovery accuracy. Additionally, the application is designed to take advantage of a high performance PMU data platform called PredictiveGrid™, developed by PingThings.
KEYWORDS
Availability is a performance criterion for repairable systems that accounts for both the reliability and maintainability properties of a component or system. It is defined as the probability that the system is operating properly when it is requested for use
Trajectory Control With MPC For A Robot Manipülatör Using ANN ModelIJMER
In this study, in a computer the dynamic motion modelling of manipulator and control of
trajectory with an algorithm this has been tested. First after dynamic motion simulation of manipulator
has been made MPC Control. The result in this study we can observe that computed torque method gives
better results than MPC methods. So in trajectory control it is approved of using computed torque
method. In last part of this study the results are estimated forward development are exemined and
suggested. The model predictive control (MPC) technique for an articulated robot with n joints is
introduced in this paper. The proposed MPC control action is conceptually different with the trajectory
robot control methods in that the control action is determined by optimising a performance index over
the time horizon. A neural network (NN) is used in this paper as the predictive model.
Worker Scheduling for Maintenance Modeling SoftwareIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
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An Imperfect Preventive Maintenance Policy Considering Reliability Limit
1. Mwaba Coster Int. Journal of Engineering Research and Applications www.ijera.com
ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 2) December 2015, pp.49-56
www.ijera.com 49|P a g e
An Imperfect Preventive Maintenance Policy Considering
Reliability Limit
Mwaba Coster*, Qiong Liu**
State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and
Engineering Huazhong University of Science and Technology Wuhan 430074, PR China
Abstract
This paper discusses an imperfect preventive maintenance model for a deteriorating repairable system with
consideration of the reliability limitand random maintenance quality. The model is derived from the
combination of failure rate adjustment and age over an infinite time horizon. The maintenance intervals are
obtained assuming both the failure rate increase factor and age restoration factor are random variables with a
uniform distribution. The optimal policy with a sensitivity analysis showing how different cost parameters affect
the long run average maintenance cost rate is presented.
Keywords: Imperfect preventive maintenance, virtual age, failure rate, reliability limit,
I. Introduction
The maintenance of deteriorating systems is
often imperfect. Previous studies have shown that the
imperfect preventive maintenance (PM) can reduce
the wear rate and aging effects of deteriorating
systems to a certain level between the conditions of
‘as good as new’ (AGAN) and ‘as bad as old’
(ABAO),and partially restore the performance and
reliability of the system so as to extend its life and
reduce the frequency of failures[1]. This is achieved
by the two commonly used policies, periodic and
sequential preventive maintenance actions. In order
to satisfy the requirements of high reliability and low
maintenance cost for aging equipment during the
wear period, a suitable sequential PM policy is
necessary.
Maintenance optimization of repairable systems
was initiated by [2]. Since then, a number of
maintenance models for repairable systems have
appeared in literature.[3]proposed the improvement
factor method to measure the restoration effect of PM
for the deteriorating systems, two maintenance
policies, i.e., single and multi-component systems.
And [4] proposed sequential imperfect PM model and
two sequential PM models called hazard rate
adjustment and age models were proposed by [5].
[6]and[7] introduced adjustment factors in
hazard rate and effective age after imperfect PM
models respectively. [8] extended model [2]into two
maintenance policies, i.e., single and multi-
component systems and observed that, the effect of
maintenance actions can be modeled using system
virtual age or failure rate functions.[9,10] introduced
the concept of virtual age to model the effect of
imperfect repair. [11] studied the modelling of the
hazard rate restoration after performing a PM
activity. These models are to determine the optimal
time interval between PMs and the number of PMs
before replacing the system by minimizing the
expected average cost over a finite or infinite time
span.[12] generalized the virtual age model to a
virtual age process for imperfect repair of repairable
systems and [13] extended the age reduction idea to
model periodic imperfect PM. [14,15] introduced two
hybrid sequential PM models incorporating failure
rate adjustment and age reduction factors. The two
models assumed that PM actions not only reduce the
effective age to a certain value but also increase the
slope of failure rate function as equipment ages.
Based on the reduction of failure intensity and
virtual age,[16] proposed two classes of imperfect
repair models based on the reduction of failure
intensity and virtual age, which is arithmetic reduction
of intensity (ARI) model and arithmetic reduction of
age (ARA) model, respectively.
[17] proposed a general PM model that
incorporates three types of PM, i.e., imperfect
preventive maintenance(IPM), perfect preventive
maintenance (PPM) and failed preventive maintenance
(FPM), and obtained an optimal PM schedule
maximizing the availability of a repairable
system.[18]considered sequential PM model for a finite
time span. They considered three models: minimal
repair, block replacement and simple replacement.[19]
built on [20] model where each PM application reduces
the effective age. They considered age reduction model
where parts of the system are non-maintainable. [21]
introduced phasic sequential PM that considers
improvement factor for machine age.[22]considered
stochastic maintenance policy for a system degradation
over a finite life time. They usedgenetic algorithm
(GA) to solve their model. The maintenance
improvement was considered stochastic. [23]
considered two types of failures, catastrophic and
RESEARCH ARTICLE OPEN ACCESS
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minor, and considered the improvement in hazard rate
function.[24]did a comparative analysis of construction
equipment failures using the classical power law
models and the new time series models; the researcher
found out that the power law models are easy to apply
and are capable of predicting reliability metrics at both
the system and subsystem levels with fair results, while
time series models based on predictive data mining
algorithms are more flexible, comprehensive, and
accurate by taking various influencing factors into
account.Although the primary criterion for judging
preventive maintenance is increasing in availability,
most of the existing optimal sequential PM policies are
developed by minimizing the expected cost rate only
without accounting for reliability limit.
This makes the system to have a very low
reliability at the time of preventive replacement or
overhaul,[25],[26],[27]because in practicehigh
reliability is usually required to avoid high probability
of system unexpected failures[28], [29]. [30]observed
that, each PM action in sequential PM model has a
different quality, which requires a large number of
failure data to estimate it. However, in real
circumstances, it is usually difficult to specifythe
quality of a PM action precisely as it depends on the
available resources, i.e., material, technological,
human, time, etc. Some researcher seven assumed that
the quality of PM as a fixed constant, which is usually
not true in many situations. In this case, it is suitable to
assume that restoration factor of PM or failure rate
increase factor is a random variable with a probability
distribution[30].
This article analyses a hybrid model of sequential
imperfect PM by minimizing the long-run average cost
rate considering reliability limit for deteriorating
repairable systems with random maintenance quality.
The proposed model regards the failure rate increase
factor and the restoration factor as random variables
with a uniform probability distribution. An example is
also presented with a discussion of parameters that
affect maintenance quality.
II. Model Description and Assumptions
a. The repairable system deteriorates with usage
and age. The planning horizon is infinite and the
times for preventive maintenance, minimal repair
and replacement is negligible.
b. The system failure rate without PM is continuous
and strictly increasing. The failure rate after the
𝑖𝑡ℎ PM is ℎ𝑖 𝑥 = 𝜃ℎ𝑖−1 𝑥 + 𝑞𝑡𝑖−1 , 0 ≤ 𝑥 < 𝑇𝑖
c. The system undergoes minimal repair upon
failures between two adjacent PM actions and
the repairs do not change the failure rate or the
system effective age.
d. The imperfect PM is performed at a sequence
𝑡1, 𝑡2, … , 𝑇𝑁−1, and the system is replaced at 𝑇𝑁
to ‘as good as new’ 𝐴𝐺𝐴𝑁 state.
e. The failure rate increase factor and restoration
factor are all random variables and follow
uniform distribution.
Notation
f(.) probability density function (pdf)
F(.) cumulative distribution function
(cdf)
Fi number of failures for the ith PM
interval
h(.) system failure rate
n number of failures for an
observed repairable system
N number of PM actions before
system replacement
N*
optimal value of N
q restoration factor immediately
after the 𝑖𝑡ℎ PM, 0 ≤ 𝑞 ≤ 1
R predetermined reliability
R(.) reliability function
ti time for the ith PM, 𝑡1 + 𝑡2+, … , 𝑇𝑁 (𝑖 =
1,2, … , 𝑁)
Ti time interval between (i-1)th and
ith PM actions 𝑖 = 1,2, … , 𝑁
u failure rate increase factor upper
limit
θ failure rate increase factor
immediately after the 𝑖𝑡ℎ PM, 𝑢 ≥ 𝜃 ≥ 1
vi system virtual age after ithPM 𝑖 =
1,2,…,𝑁
β Weibull shape parameter (β > 1)
λ Weibull scale parameter (λ > 0) cm, cp, cr
minimal repair, PM and system
replacement cost respectively.
C(N), C(N*)long run average cost rate with N
and N* cycles respectively.
2.1 The failure rate and reliability function of the
model
Consider a repairable system which is put into
operation at time t = 0 and is minimally repaired
between two adjacent preventive maintenance (PM)
actions upon failure. Based on Kijima type virtual
age idea, the virtual age 𝜗𝑖 of the equipment after the
ith PM can be given by [9].
𝜗𝑖 = 𝜗𝑖−1 + 𝑞𝑇𝑖 = 𝑞𝑡𝑖 𝑖 = 1,2, … , 𝑁 (1)
When 𝑞 = 0 , it implies the equipment has been
restored to ‘as good as new’ (AGAN) state, i.e.,
perfect maintenance has been performed; while
𝑞 = 1 means the maintenance action has no effect on
the condition of the equipment and it remains ‘as bad
as old’(ABAO),i.e., minimal repair or imperfect
maintenance has been performed.
According to[9], if the equipment’s virtual age 𝜗𝑖−1
after the (i-1)th PM, then the time interval x between
the (i-1)th and ith PM has the following conditional
cumulative distribution function (cdf)
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𝐹 𝑥|𝜗𝑖−1 =
𝐹 𝑥+𝜗 𝑖−1 −𝐹 𝜗 𝑖−1
1−𝐹 𝜗 𝑖−1
= 1 −
𝑅 𝑥+𝜗 𝑖−1
𝑅 𝜗 𝑖−1
, 0 ≤ 𝑥 ≤ 𝑇𝑖 (2)
where𝐹 ∙ and R ∙ are cdf and reliability functions
respectively.
The reliability function of the Weibull process for the
interval x can be expressed as [31-33]
𝑅 𝑥 = 𝑒𝑥𝑝 −𝜆𝑥 𝛽
, 0 ≤ 𝑥 ≤ 𝑇𝑖 (3)
where λ 𝜆 > 0 and β 𝛽 > 1 are the scale and shape
parameters of the Weibull process respectively.
Adopting the Weibull process, being the widely used
in Kijima type virtual age model for repairable
systems due to its flexibility, to describe the
imperfect maintenance based on equations (1) to
(3).The conditional reliability of the equipment
within the time interval can be derived as follows
𝑅 𝑥|𝜗𝑖−1 =
𝑅 𝑥+𝜗 𝑖−1
𝑅 𝜗 𝑖−1
= 𝑒𝑥𝑝 −𝜆 𝑥 +
𝑞𝑡𝑖−1𝛽− 𝑞𝑡𝑖−1𝛽0≤ 𝑥≤ 𝑇𝑖 (4)
Taking the negative derivative with respect to x in
equation (4), we get the corresponding probability
density function (pdf)
𝑓 𝑥|𝜗𝑖−1 =
−𝑑𝑅 𝑥|𝜗 𝑖−1
𝑑𝑥
= 𝜆𝛽 𝑥 +
𝑞𝑡𝑖−1𝛽−1exp− 𝜆𝑥+𝑞𝑡𝑖−1𝛽− 𝑞𝑡𝑖−1𝛽
0 ≤ 𝑥 ≤ 𝑇𝑖 (5)
Thus, the conditional failure rate can be obtained by
ℎ 𝑥|𝜗𝑖−1 =
𝑓 𝑥|𝜗 𝑖−1
𝑅 𝑥|𝜗 𝑖−1
= 𝜆𝛽 𝑥 + 𝑞𝑡𝑖−1
𝛽−1
, 0 ≤ 𝑥 ≤
𝑇𝑖 (6)
The failure rate of deteriorating repairable
systems normally increases with usage and age
especially during the wear period. Therefore, the
system would need more frequent maintenance
actions as the failure rate of the ith PM interval
increases more quickly than that of the (i-1)th PM
interval. For the proposed hybrid model, the failure
rate increase factor 𝜃 is added to the Kijima type
virtual age model to determine the maintenance
policy.
Assuming that the failure rate of a deteriorating
repairable system after the ithPM is: ℎ𝑖 𝑥 =
𝜃ℎ𝑖 𝑥 + 𝑞𝑡𝑖−1 , then ℎ𝑖 𝑥 = 𝜃 𝑖−1
ℎ 𝑥 + 𝑞𝑡𝑖−1 ,
𝑤ℎ𝑒𝑟𝑒 𝜃(𝜃 ≥ 1) is the failure rate increase factor
and is a random variable, and ℎ 𝑥 is the equipment
failure rate when there are no PM actions. Therefore,
from equations (4) and (6), the combined reliability
and failure rate function of the proposed model
within the time interval Ti will be
𝑅𝑖 𝑥 = 𝑒𝑥𝑝 −𝜆𝜃 𝑖−1 𝑥+𝑞𝑡 𝑖−1
𝛽 − 𝑞𝑡 𝑖−1
𝛽
,
0 ≤ 𝑥 ≤ 𝑇𝑖 (7)
and ℎ𝑖 𝑥 = 𝜆𝛽𝜃 𝑖−1
𝑥 + 𝑞𝑡𝑖−1
𝛽−1
0 ≤ 𝑥 ≤ 𝑇𝑖 (8)
respectively. If the failure rate is used to express the
reliability function, then reliability function is
expressed as
𝑅𝑖 𝑥 = 𝑒𝑥𝑝 − ℎ𝑖
𝑥
0
𝑥 𝑑𝑥 =
𝑒𝑥𝑝 − 𝜆𝛽𝜃 𝑖−1𝑥
0
𝑥 + 𝑞𝑡𝑖−1
𝛽−1
𝑑𝑥 0 ≤ 𝑥 ≤ 𝑇𝑖
(9)
In practice, the degree of each preventive
maintenance action depend on the available
resources, i.e., material, technological, human, time
etc. [10] extended the improvement factor q and
observed that it is a random variable with a value
between 0 and 1. [30]pointed out that the failure rate
increase factor 𝜃 is not a fixed constant but usually
falls within an interval.
In this particular case, it is assumed that the
improvement factor 𝑞 0 ≤ 𝑞 ≤ 1 and the failure
rate increase factor 𝜃 𝑢 ≥ 𝜃 ≥ 1 follow uniform
distribution. Therefore, the corresponding cdfs are
expressed by
𝐹 𝑞 = 𝑞, 0 ≤ 𝑞 ≤ 1
(10)
and 𝐹 𝜃 =
𝜃−1
𝑢−1
, 1 ≤ 𝜃 ≤ 𝑢
(11)
respectively, where u is a constant and the upper limit
of the failure rate increase factor.
2.2 Derivation of preventive maintenance
intervals
Integrating equation (8) with respect to x in the
interval [0, Ti], we get the number of failures Fi for
theithPM interval
𝐹𝑖 = ℎ𝑖
𝑇 𝑖
0
𝑥 𝑑𝑥
= 𝜆𝛽𝜃 𝑖−1
𝑥 + 𝑞𝑡𝑖−1
𝛽−1
𝑇 𝑖
0
𝑑𝑥 = 𝜆𝑇1
𝛽
, 𝑖 = 1
𝜆𝛽 𝜃𝑑𝐹 𝜃
𝑢
1
𝑖−1
𝑥
1
0
𝑇 𝑖
0
+ 𝑞𝑡𝑖−1
𝛽−1
𝑑𝐹 𝑞 𝑑𝑥 =
= 𝜆
𝑢 + 1
2
𝑖−1
𝑇𝑖 + 𝑡𝑖−1
𝛽+1
− 𝑡𝑖−1
𝛽+1
− 𝑇𝑖
𝛽+1
𝛽 + 1 𝑡𝑖−1
,
0 ≤ 𝑥 ≤ 𝑇𝑖, 𝑖 = 2,3, … , 𝑁 (12)
Assuming that an imperfect preventive maintenance
is carried out once the system’s reliability falls to the
predetermined minimum value R. From equation (9),
the system’s reliability is expressed as
𝑒𝑥𝑝 − 𝜆𝛽𝜃 𝑖−1
𝑥 + 𝑞𝑡𝑖−1
𝛽−1𝑇 𝑖
0
𝑑𝑥 = 𝑅, 𝑖 =
1,2, … , 𝑁 (13)
Taking natural logarithm of both sides of equation
(13) leads to
𝜆𝛽𝜃 𝑖−1𝑇 𝑖
0
𝑥 + 𝑞𝑡𝑖−1
𝛽−1
𝑑𝑥 = −𝑙𝑛𝑅, 𝑖 = 1,2, … , 𝑁
(14)
Therefore, using equations (12) and (14), we get
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𝜆𝑇1
𝛽
= −𝑙𝑛𝑅, 𝑖 = 1
𝜆
𝛽+1
𝑢+1
2
𝑖−1 𝑇𝑖
𝛽+1
+𝑡 𝑖−1
𝛽+1
− 𝑇 𝑖+𝑡 𝑖−1
𝛽 +1
𝑡 𝑖−1
= 𝑙𝑛𝑅, 𝑖 = 2,3, … , 𝑁
(15)
The sequence time intervals𝑇𝑖, 𝑖 = 1,2, … , 𝑁 can be
determined iteratively using equation (15) as follows
𝑇1 = −𝑙𝑛
𝑅
𝜆
1
𝛽
, 𝑖 = 1
𝑇𝑖
𝑘+1
=
𝑇𝑖
𝑘
+ 𝑡𝑖−1
𝛽+1
−
𝑡𝑖−1
𝛽+1
+
𝛽+1 𝑙𝑛𝑅
𝜆
2
𝑢+1
𝑖−1
𝑡𝑖−1
1
𝛽+1
𝑖 = 2,3, … , 𝑁
(16)
where 𝑇𝑖
𝑘+1
𝑎𝑛𝑑 𝑇𝑖
𝑘
are (k+1)th and kth iteration
results respectively
1.2 Optimal values of N and C(N)
According to [5],the long run average cost rate C(N)
with N cycles is
𝐶 𝑁 =
𝐶 𝑚 𝐹𝑖+ 𝑁−1 𝐶 𝑝 +𝐶 𝑟
𝑁
𝑖=1
𝑇 𝑖
𝑁
𝑖=1
=
𝐶 𝑚 ℎ 𝑖 𝑥 𝑑𝑥 + 𝑁−1 𝐶 𝑝 +𝐶 𝑟
𝑇 𝑖
0
𝑁
𝑖=1
𝑇 𝑖
𝑁
𝑖=1
(17)
where𝐶 𝑚 , 𝐶𝑝 𝑎𝑛𝑑 𝐶𝑟 are the costs for minimal repair,
PM and system replacement respectively
Substituting 𝐹𝑖 from equation (12) into equation (17)
yields
𝐶 𝑁 =
𝐶 𝑟 −𝐶 𝑚 𝑙𝑛𝑅
−𝑙𝑛 𝑅
𝜆
1
𝛽
, 𝑖 = 1
𝐶 𝑚 𝜆
𝛽+1
𝑢+1
2
𝑖−1 𝑇 𝑖+𝑡 𝑖−1
𝛽 +1−𝑡 𝑖−1
𝛽+1
−𝑇𝑖
𝛽+1
𝑡 𝑖−1
−𝐶 𝑚 𝑙𝑛𝑅 + 𝑁−1 𝐶 𝑝 +𝐶 𝑟
−
𝑙𝑛𝑅
𝜆
1
𝛽
+ 𝑇 𝑖
𝑁
𝑖=2
𝑁
𝑖=2
𝑖 = 2,3, … , 𝑁
,
(18)
From equation (18), C(N) is a function of only N ,
therefore the optimal values N* of N and C(N*) of
C(N) can be found by substituting N* into equation
(18)
The optimal value N* must satisfy the two
inequalities 𝐶 𝑁 + 1 ≥ 𝐶 𝑁 and 𝐶 𝑁) <
𝐶𝑁−1 which implies that
𝑇𝑖
𝑁
𝑖=1 ℎ 𝑁+1
𝑇 𝑁−1
0
𝑥 𝑑𝑥 −
𝑇𝑁+1 ℎ𝑖 𝑥
𝑇 𝑖
0
𝑁
𝑖=1 𝑑𝑥
≥
𝑇 𝑁+1 𝐶 𝑟− 𝑇 𝑖− 𝑁−1 𝑇 𝑁−1
𝑁
𝑖=1 𝐶 𝑝
𝐶 𝑚
(19)
and
𝑇 𝑁 𝐶 𝑟 − 𝑇 𝑖− 𝑁−1 𝑇 𝑁+1
𝑁−1
𝑖=1 𝐶 𝑝
𝐶 𝑚
< 𝑇𝑖
𝑁−1
𝑖=1 ℎ 𝑁
𝑇 𝑁
0
𝑥 𝑑𝑥 −
𝑇𝑁 ℎ𝑖
𝑇 𝑖
0
𝑁−1
𝑖=1 𝑥 𝑑𝑥 (20)
Let
𝐿 𝑁 = 𝑇𝑖
𝑁
𝑖=1 ℎ 𝑁+1
𝑇 𝑁+1
0
𝑥 𝑑𝑥 −
𝑇𝑁+1 ℎ𝑖
𝑇 𝑖
0
𝑁
𝑖=1 𝑥 𝑑𝑥
and𝐵 𝑖 = ℎ𝑖
𝑇 𝑖
0
𝑥 𝑑𝑥
then, subtracting the right-hand side of inequality
(20) from the left-hand side of inequality (19), we get
𝐿 𝑁 − 𝐿(𝑁 − 1 = 𝑇𝑖
𝑁
𝑖=1
𝐵 𝑁 + 1 − 𝑇𝑁+1
𝐵 𝑖
𝑁
𝑖=1
− 𝑇𝑖
𝑁−1
𝑖=1
𝐵 𝑁 + 𝑇𝑁 𝐵 𝑖
𝑁−1
𝑖=1
= 𝐵 𝑁 + 1 − 𝐵 𝑁 𝑇𝑖 + 𝑇𝑁 − 𝑇𝑁+1
𝑁−1
𝑖=1
𝐵 𝑖 + 𝑇𝑁 𝐵 𝑁 + 1 − 𝑇𝑁+1 𝐵 𝑁
𝑁−1
𝑖=1
(21)
From equation (14),
𝑇𝑖 = 𝑞𝑡𝑖−1
𝛽
−
𝑙𝑛𝑅
𝜆𝜃 𝑖−1
1
𝛽
− 𝑞𝑡𝑖−1, 𝑖 = 2,3, … , 𝑁
(22)
Since lim𝑖→∞ 𝜃 𝑖−1
= ∞ 𝜃 > 1 thus lim𝑖→∞ 𝑇𝑖 = 0 .
This implies that 𝑇𝑖 is a strictly decreasing function of
𝑁 and 𝑇𝑖 > 𝑇𝑖+1 . Conversely, from equation (14),
𝐵 𝑁 + 1 − 𝐵 𝑁 = 0. Consequently, the last term
of equation (21)
𝑇𝑁 𝐵 𝑁 + 1 − 𝑇𝑁+1 𝐵 𝑁 >
𝑇𝑁+1 𝐵 𝑁 + 1 − 𝑇𝑁+1 𝐵 𝑁 =
= 𝑇𝑁+1 𝐵 𝑁 + 1 − 𝐵 𝑁 = 0
Therefore, 𝐿 𝑁 − 𝐿 𝑁 − 1 > 0. This implies that
𝐿 𝑁 is strictly increasing in N and tends to ∞ as
N→ ∞. Therefore, based on [4], when the hazard
rate ℎ 𝑡 is a continuous and strictly increasing
function, then there exists a finite and unique N*
which satisfies the inequalities (21) and (22).
III. Numerical Example
This section presents a numerical example to
illustrate the proposed maintenance model.
A piece of manufacturing equipment is observed
to deteriorate with increased usage and age,
undergoes minimal repair upon failures between two
adjacent PM actions and follows the Weibull failure
process. The maximum likelihood estimates of β and
λ are [34]
𝛽 =
𝑛
𝑙𝑛
𝑋 𝑛
𝑋 𝑗
𝑛
𝑗=1
, 𝜆 =
𝑛
𝑋 𝑛
𝛽 (23)
Using historical maintenance dataof the equipment
under consideration, the input parameters are given
as follows: β = 1.4753,λ = 0.00003, R = 0.7, u = 1.1,
Cp = 15000, Cm= 30000, Cr = 900 000.
Table 1 gives the preventive maintenance time
intervals and it is observed that the PM time intervals
gradually decrease along with the increase in
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www.ijera.com 53|P a g e
maintenance actions. This implies that the system is
subject to degradation with usage and age.
Table 1 PM time intervals
i Ti ti
1 578.43 578.43
2 411.04 989.47
3 342.53 1332.00
4 297.86 1629.86
5 268.34 1898.20
6 220.28 2139.95
7 202.15 2360.23
8 186.51 2562.38
9 172.78 2748.89
10 160.61 2921.67
11 149.69 3082.28
12 139.84 3231.97
13 130.89 3371.81
14 122.71 3502.70
15 115.21 3525.41
16 108.30 3740.62
17 101.92 3848.92
18 96.00 3950.84
19 90.50 4046.84
20 85.39 4137.84
21 80.62 4222.73
22 76.34 4303.35
23 72.02 4379.69
Figure 1 shows the failure rate of the imperfect
sequential preventive maintenance policy. It can be
observed that the equipment failure rate decrease
after PM actions between the initial and 7th
cycles but
increases thereafter. This is due to the fact that,
equipment is likely to suffer failures during the early
stages of exploitation (infant mortality) due to
manufacturing errors. The corrective maintenance
actions are basically meant to correct such errors. The
imperfect PM that follows thereafter reduces the
equipment’s effective age to a certain value rather
than to zero. Since the failure rate is a function of the
effective age and equipment usage, the initial failure
rate value right after the PM action is not equivalent
to zero. Imperfect PM changes the slope of the failure
rate function and makes it more and more high due to
deterioration process. When the failure rate increases
and its function exceeds the ratio of the failure rate
value just before PM to the equipment’s effective age
right after PM, then the failure rate right after each
PM is increasing rather than decreasing at the
corresponding PM time. Therefore, PM reduces the
failure rate at first and then increases it.
Fig. 1 Failure rate of PM
IV. Sensitivity Analysis and Discussion
From equation (18) it is evident that the long-run
average cost rate is affected by the five cost
parameters Cm,Cp, Cr, R and u when β and λ are
known. For analytical purposes, cost ratios
Cm/Cp ,Cr/Cp are used. To show how the optimal
maintenance policy depend on the different cost
parameters, only one cost parameter is changed at a
time while others remain constant. The optimal
results are shown in Tables 2 to 5 respectively. The
initial input parameters are highlighted in the tables.
4.1 Effect of u
Table 2 and Fig.2 show the optimal maintenance
number N* and its corresponding long-run cost
C(N*). The optimal maintenance number
N*decreases as uand the long run cost C(N*)
increases. Therefore,during equipment wear period it
is necessary to reduce maintenance actions before
replacement or overhaul.
Table2 Optimum N*,𝑇𝑁
∗
and C(N*) for differentu
U=1.1 U=1.2 U=1.3
N* TN
*
C(N*) N* TN
*
C(N*) N* TN
*
C(N*)
20 90.5 297.06 15 122.71 318.46 13 139.84 338.32
Fig.2 Long-run cost and PM intervals and number of
PM actions with different u
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ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 2) December 2015, pp.49-56
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4.2 Effect of R
Table 3 and Fig.3 shows that the optimal
maintenance number N* decrease and the
corresponding long-run cost C(N*) increase with an
increase of R. With higher reliability, the long-run
cost of frequent maintenance is higher whereas the
length of time interval between PM actions becomes
shorter and shorter. This implies that, it is worthwhile
and necessary to increase the number of maintenance
actions for equipment with a higher reliability
requirement.
Table3. Optimum N*, 𝑇𝑁
∗
, and C(N*) for different R
R=0.6 R=0.7 R=0.8
N* TN* C(N*) N* TN* C(N*) N* TN* C(N*)
18 128.8 248.7 20 90.5 297.1 22 58.13 385.3
Fig.3 Long-run cost and PM intervals and number of
PM actions with different R
4.3 Effect of Cm/Cp
Table 4 Optimum N* and C(N*) for different Cm/Cp
Cm/Cp 0.5 1.0 1.5 2.02.5 3.0 5.0 10.0
N* 25 23 21 20 19 18 15 11
C(N*) 259.5 273.1 285.4 297.1 308.4 319.3 360.2
448.6
From Table 4, as the cost ratio Cm/Cp increases, the
optimal maintenance number N* decreases while the
corresponding long-run cost C(N*) increases which
implies that, the higher the cost ratio Cm/Cp, the less
the cost-effectiveness PM work is.
4.4 Effect of Cr/Cp
Table 5 gives the results of the optimum N* and
C(N*) for different Cr/Cp. It is observed that both the
optimal maintenance number N* and the
corresponding long-run cost C(N*) increase as the
cost ratio Cr/Cp increase.
Generally, the more expensive the equipment is, the
more maintenance actions are required and the higher
is the cost.
Table 5 Optimum N* and C(N*) for different Cr/Cp
Cr/Cp 10 20 40 60 80 100
N*
5 10 16 20 24 26
C(N*
) 106.42 155.03 230.97 297.06 358.68 417.52
V. Conclusions
A sequential imperfect maintenance policy for
deteriorating system with variable maintenance
quality considering reliability limit is presented. In
practice, it is usually difficult to determine the quality
of maintenance actions as each sequential
maintenance action has a different maintenance
quality due to the prevailing operating conditions and
available resources. The optimal maintenance policy
is optimized by assuming that the failure rate increase
factor and the restoration factor are both random
variables with uniform probability distribution and
that, the equipment under consideration obeys
weibull process. The sensitivity analysis shows that
in order to achieve optimal practical requirements of
high reliability, it is necessary to consider either
system’s reliability limit or failure rate.
VI. Acknowledgements
This work is supported by the Funds for
International Cooperation and Exchange of the
National Natural Science Foundation of China(grant
No.51561125002 ) , National Natural Science
Foundation of China (grant no.51035001); and the
National Natural Science Foundation of China (grant
no.51275190)
References
[1.] Pham H and Wang H , Imperfect repair.
European Journal ofOperational
Research94, 1996,425–438.
[2.] Barlow, R. E.; Hunter, L. C.(1960).
Optimum preventive maintenance policies,
Operations Research 8,1960,90–100.
[3.] Malik M A K , Reliable Preventive
MaintenanceScheduling,” AIIE Transaction,
9, 1979, 221-228.
[4.] Nakagawa T (1986). Periodic and sequential
preventivemaintenance policies. Journal of
Applied Probability 23,1986,536-542.
[5.] Nakagawa T , Sequential imperfect
preventivemaintenance policies. IEEE
Transactions on Reliability37(3),1988,
295–298.
[6.] Nakagawa T (1980). A summary of
imperfect preventivemaintenance policies
with minimal repair. RAIROOperations
Research 14,1980,249–255.
[7.] Lie C H and Chun Y H (1986). An
algorithm for preventivemaintenance policy.
IEEE Transactions on Reliability35(1) ,
1986, 71–75.
[8.] Nguyen D G and Murthy D N P, Optimal
preventivemaintenance policies for
repairable systems.Operations. Research
29(6),1981,1181–1194.
7. Mwaba Coster Int. Journal of Engineering Research and Applications www.ijera.com
ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 2) December 2015, pp.49-56
www.ijera.com 55|P a g e
[9.] Kijima M, Morimura H and Suzuki Y,
Periodicalreplacement problem without
assuming minimalrepair. European Journal
of Operational Research37,1988 , 194–
203.
[10.] Kijima, M.(1989). Some results for
repairable systems withgeneral repair.
Journal of applied Probability26,1989, 89–
102.
[11.] Chan, JK and L Shaw, Modelling repairable
systems with failure rates that depend on age
and maintenance. IEEE Transactions on
Reliability 42,1993, 566–570.
[12.] Guo R, Ascher H, and Love C E,
Generalizedmodels of repairable systems: a
survey via stochasticprocesses formalism.
Orion. 16(2),2000, 87–128.
[13.] Liu X, Makis V, and Jardine A K S (1995).
A replacementmodel with overhauls and
repairs. Naval ResearchLogistics42: 1063–
1079.
[14.] Lin D, Zuo M J, and Yam R C M,
Generalsequential imperfect preventive
maintenancemodels. International Journal
of Reliability, Quality and Safety
Engineering 7,2000,253–266.
[15.] Lin D, Zuo M. J, and Yam R C M,
Sequentialimperfect preventive maintenance
models with twocategories of failure modes.
Naval Research Logistics 48,2001,172–182.
[16.] Doyen L and Gaudoin O, Classes of
imperfectrepair models based on reduction
of failure intensityor virtual age. Reliability
Engineering and System Safety 84,2004, 45–
56.
[17.] Sheu, SH, YB Lin and GL Liao , Optimum
policies for a system with general imperfect
maintenance. Reliability Engineering and
System Safety 91,2006, 362–369.
[18.] Nakagawa T and Mizutani S, A summary of
maintenance policies for a finite interval,
Reliability Engineering and System
safety,94,2009, 89-96.
[19.] Michael Batholomew Biggs, Ming J.Zuo
and Xiaohu Li, Modelling and Optimizing
Sequential Imperfect Preventive
Maintenance, Reliability Engineering and
System safety, 94, 2009, 53-62.
[20.] Kijima M and Nakagawa T, Replacement
policies of a shock model with imperfect
preventive maintenance, European journal
of Operations Research, 57,1992, 100-110
[21.] QuYuxiang and Wu Su, Phasic Sequential
Preventive Maintenance Policy Based on
Imperfect Maintenance for deteriorating
Systems, Chinese journal of mechanical
Engineering, 47(10),2011, 164-170
[22.] Liu Yu, Yanfeng Li, Hong-Zhong Huang
and YuanhuiKuang, An optimal sequential
preventive maintenance policy under
stochastic maintenance quality, Structure
and infrastructure Engineering: Maintenance
Management, Life-Cycle Design and
Performance, 7(4),2011, 315-322.
[23.] Shey-HueiSheu, Chin-Chih Chang and Yen-
Luan Chen, An Extended Sequential
Imperfect maintenance model with
Improvement Factors, Communications in
Statistics-Theory and Methods, 41(7),2012,
1269-1283.
[24.] Hongqin Fan, A comparative analysis of
construction equipment failures using power
law models and time series models.
International Symposium on Automation and
Robotics in Construction. Eindhoven,
Netherlands,2012, June 26-29.
[25.] Jayabalan V and Chaudhuri D, Cost
optimizationof maintenance scheduling for a
system with assuredreliability. IEEE
Transactions on Reliability41(1), 1992, 21–
25.
[26.] Zhou X J, Xi L F, and Lee J (2007).
Reliability-canteredpredictive maintenance
scheduling for a continuouslymonitored
system subject to degradation.Reliability
Engineering and System Safety 92,2007,
530–534.
[27.] Liao W Z, Pan E S, and Xi L F, Preventive
maintenancescheduling for repairable
system with deterioration.Journal of
Intelligent Manufacturing 4, 2010.
[28.] Tsai Y A, A Study of availability centred
preventive maintenance for multi-
component systems, Reliability Engineering
and system safety, 84 ,2004, 261-270.
[29.] Kamran S. Moghaddam& John S. Usher, A
new multi-objectiveoptimization model for
preventive maintenance and replacement
scheduling of multi-componentsystems,
Engineering Optimization, 43(7), 2011, 701-
719.
[30.] Wu S and Clements-Croome D (2005).
Preventive maintenancemodels with random
maintenance quality.Reliability Engineering
and System Safety90, 2005, 99–105.
[31.] Yanez M, Joglar F, and Modarres M,
Generalizedrenewal process for analysis of
repairable systemswith limited failure
experience. Reliability Engineering
SystemSafety77,2002, 167–180.
[32.] Mettas A and Zhao W, Modelling and
analysis ofrepairable systems with general
repair. InProceedings of the annual
reliability and maintainabilitysymposium,
Alexandria, Virginia. 2005, 176–182.
8. Mwaba Coster Int. Journal of Engineering Research and Applications www.ijera.com
ISSN: 2248-9622, Vol. 5, Issue 12, (Part - 2) December 2015, pp.49-56
www.ijera.com 56|P a g e
[33.] Veber B, Nagode M, and Fajdiga M,
Generalizedrenewal process for repairable
systems based onfinite Weibull mixture.
Reliability Engineering and System
Safety93,2008, 1461–1472.
[34.] Coetzee J L, The role of NHPP models in
the practicalanalysis of maintenance failure
data. ReliabilityEngineering and System
Safety56, 1997, 161–168.