This research is conducted to develop inventory policy of aircraft consumable spare parts which are needed on aircraft maintenance activity . In this research, we used periodic review model to determine the optimal policy of aircraft spare parts inventory. By using the periodic review model, we find optimal period of inventory review and maximum level of inventory. The optimal decision is determined based on the minimum total cost. We have classified consumable spare parts using ABC method to categorize them based on their dollar contribution and demand frequency. Therefore in this research, we focus on managing the inventory level for spare parts on class C. The result from this study shows that the proposed periodic review policy result in lower total inventory cost compared the the company policy. The proposed policy gives an average saving 35.38 %.
Determination Inventory Level for Aircraft Spare Parts Using Continuous Revie...Waqas Tariq
In this paper, we determine ordering quantity and reorder point for aircraft consumable spare parts. We use continuous review model to propose a spare part inventory policy that can be used in a aircraft maintenance company in Indonesia. We employ ABC classification system to categorize the spare parts based on their dollar contribution. We focus our research on managing the inventory level for spare parts on class A and B which commonly known as important classes. The result from the research indicates that the continuous review policy gives a significant amount of saving compared to an existing policy used by the company.
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.
Cost Implication of Inventory Management in Organised SystemsDr. Amarjeet Singh
This paper investigates the role of cost implication in
inventory management in order to improve Institutions’
Stores. The study takes a critical look at the costs involved and
the use of economic order quantity as a tool that minimizes the
total inventory costs, the time saved between the manual and
the automated operational system using a Nigerian University
Store, AYZ University (not the real name because of the
ethical issue), as a case study. The study was being guided by
the following objectives; to have stocks available when
required, to maintain accurate stock records and facilities, and
to recommend area improvement of the inventory system at
AYZ University Stores. Findings revealed that the economic
order quantity is seen as a control technique that is attributed
to determine the inventory costs and how it can be minimized.
The data collected from the store were analyzed and the
results obtained shows that the existing system which is
majorly manual based is not effective when it comes to time
management and efficiency. A new automated system,
computerized maintenance store system (CMMS) was
proposed for development and implementation for the AYZ
University Store for her end users of the store and her clients
from within and outside the University system. This would be
greatly improved in terms of both financial and time cost of
inventory management.
MCDM Techniques for the Selection of Material Handling Equipment in the Autom...IJMER
Abstract: Material Handling Equipments are utilized in different shops of an automobile industry.
For culling congruous Material Handling Equipment, it is felt that some Multi Criteria Decision
Making Methods must be used due to their ability of converting an intricate quandary to a paired
comparison. These methods are predicated on some relative Criteria and Sub-criteria. Certain
methods such as; Analytic Hierarchy Process (AHP), Fuzzy Analytic Hierarchy Process (FAHP), and
Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) Method have to be utilized
for solving the quandary of Material Handling Equipment cull in different shops of automobile
industry. For solving these quandaries, some criteria (Material, Move, and Method) are culled.
The main conclusions drawn from this study are that, Method criteria is more consequential for
culling Material Handling Equipment, and Conveyor System is more efficient and precise Equipment
for Handling the Material in shop floor of any automobile industry. The focus of this research is in
the area of Cull of Material Handling Equipment in automobile industry. Cull of congruous Material
Handling Equipment is very paramount for reducing manufacturing cycle time, and cost of
manufacturing.
A Modified PSO Based Solution Approach for Economic Ordered Quantity Problem ...irjes
This paper presents formulation of Economic Ordered Quantity (EOQ) problem considering Order
Size Limits, Stock Limits and Prohibited Ordering Segments, after that a modified PSO algorithm that utilizes
the PSO with double chaotic maps is presented to solve this problem. In proposed approach, the logistic map
and lozi map are applied alternatively to the velocity updating function of the particles. Using PSO with
irregular velocity updates which is performed by these maps forces the particles to search greater space for best
global solution. However the random function itself derived from a well-defined mathematical expression which
limits its redundancy hence in the paper we are utilizing the two different chaotic maps which are used
alternatively this mathematically increased the randomness of the function. The simulation of the algorithm for
the formulated EOQ problem verifies the effectiveness and superiority of the algorithm over standard
algorithms for such a complex problem which are difficult to solve by analytical approaches.
Determination Inventory Level for Aircraft Spare Parts Using Continuous Revie...Waqas Tariq
In this paper, we determine ordering quantity and reorder point for aircraft consumable spare parts. We use continuous review model to propose a spare part inventory policy that can be used in a aircraft maintenance company in Indonesia. We employ ABC classification system to categorize the spare parts based on their dollar contribution. We focus our research on managing the inventory level for spare parts on class A and B which commonly known as important classes. The result from the research indicates that the continuous review policy gives a significant amount of saving compared to an existing policy used by the company.
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.
Cost Implication of Inventory Management in Organised SystemsDr. Amarjeet Singh
This paper investigates the role of cost implication in
inventory management in order to improve Institutions’
Stores. The study takes a critical look at the costs involved and
the use of economic order quantity as a tool that minimizes the
total inventory costs, the time saved between the manual and
the automated operational system using a Nigerian University
Store, AYZ University (not the real name because of the
ethical issue), as a case study. The study was being guided by
the following objectives; to have stocks available when
required, to maintain accurate stock records and facilities, and
to recommend area improvement of the inventory system at
AYZ University Stores. Findings revealed that the economic
order quantity is seen as a control technique that is attributed
to determine the inventory costs and how it can be minimized.
The data collected from the store were analyzed and the
results obtained shows that the existing system which is
majorly manual based is not effective when it comes to time
management and efficiency. A new automated system,
computerized maintenance store system (CMMS) was
proposed for development and implementation for the AYZ
University Store for her end users of the store and her clients
from within and outside the University system. This would be
greatly improved in terms of both financial and time cost of
inventory management.
MCDM Techniques for the Selection of Material Handling Equipment in the Autom...IJMER
Abstract: Material Handling Equipments are utilized in different shops of an automobile industry.
For culling congruous Material Handling Equipment, it is felt that some Multi Criteria Decision
Making Methods must be used due to their ability of converting an intricate quandary to a paired
comparison. These methods are predicated on some relative Criteria and Sub-criteria. Certain
methods such as; Analytic Hierarchy Process (AHP), Fuzzy Analytic Hierarchy Process (FAHP), and
Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) Method have to be utilized
for solving the quandary of Material Handling Equipment cull in different shops of automobile
industry. For solving these quandaries, some criteria (Material, Move, and Method) are culled.
The main conclusions drawn from this study are that, Method criteria is more consequential for
culling Material Handling Equipment, and Conveyor System is more efficient and precise Equipment
for Handling the Material in shop floor of any automobile industry. The focus of this research is in
the area of Cull of Material Handling Equipment in automobile industry. Cull of congruous Material
Handling Equipment is very paramount for reducing manufacturing cycle time, and cost of
manufacturing.
A Modified PSO Based Solution Approach for Economic Ordered Quantity Problem ...irjes
This paper presents formulation of Economic Ordered Quantity (EOQ) problem considering Order
Size Limits, Stock Limits and Prohibited Ordering Segments, after that a modified PSO algorithm that utilizes
the PSO with double chaotic maps is presented to solve this problem. In proposed approach, the logistic map
and lozi map are applied alternatively to the velocity updating function of the particles. Using PSO with
irregular velocity updates which is performed by these maps forces the particles to search greater space for best
global solution. However the random function itself derived from a well-defined mathematical expression which
limits its redundancy hence in the paper we are utilizing the two different chaotic maps which are used
alternatively this mathematically increased the randomness of the function. The simulation of the algorithm for
the formulated EOQ problem verifies the effectiveness and superiority of the algorithm over standard
algorithms for such a complex problem which are difficult to solve by analytical approaches.
The main objective of this study is to increase the productivity against the demand. The Quality related issue regarding material&
material shortage online is not in the scope of this study. Taking a value stream perspective means working on the big picture, nota just
individual process; and not a just optimization but an actual improvement. It covers value adding as well as non-value-adding activities. This
study also includes layout improvement and time study report.
This research shows marking benefit associated with the implementation of lean program because this project shows an industrial case
study of MCCB manufacturing Assembly line.
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.
Enhancement of the performance of an industry by the application of tqm conceptseSAT Journals
Abstract Nowadays many companies are unable to prove their performance, because they do not practice the TQM concepts in- total. In order to increase the awareness, certain TQM techniques are suggested to enhance overall performance of the organisations. Here an effort is made to apply two important basic concepts of TQM which are i)continuous improvement of production process by applying newer and innovative methods ii)establishing performance measures for the processes .This paper uses the real experimental results of cartons making industry which comprises the four machines such as Printing , Punching , Gluer and Lamination machines. We get all the machines input and output details, and then made certain suggestions based on the input values of all the four machines. Presently the four machines output values such as Availability, Performance, Quality and Overall Equipment Effectiveness are very low compared with the world class industry. In order to increase them it is suggested to reduce the downtime and other non-productive time by adopting certain simple TQM techniques. The new improved values found to be much higher than the existing values. Keywords: Total Quality Management, Availability, Performance, Quality, Overall Equipment Effectiveness, Quality Improvement.
Bayesian approach for spare parts replenishment policies under uncertaintiesIJERD Editor
The legislative constraints, the need to optimize the dismantling process, the introduction of recycled
parts on the spare parts market are reinforced since the systems in end-of-life phase have become increasingly
profitable. There are few works that treat recycled spare parts integration problem in economic models of
inventory control. These works do not consider uncertainty. In order to manage more realistically the inventory
control of spare parts, we propose a probabilistic model formalized by a Bayesian network. The model is used to
identify the best purchase policy. More precisely, it allows choosing the best proportions between new spare
parts (NSP) and recycled spare parts (RSP) by taking into account the traditional criteria of inventory control
and the availability of the spare parts on the market. The proposed method provides a decision-making tool for
manufacturers who are interested both in reducing the costs of stocks and guaranteeing a minimal availability in
an uncertain environment.
For a company to continue business, the role of the Spare Parts department is very important. Whether or not the part activities are properly controlled, can greatly influence the company’s success.
The system control among other things is vitally important to the Spare Business Unit (SBU) control, for effective operation of actual SBU.
Engine Stock Control Using the concept of U curve technique, it is delivering the best solution based on Aircraft on ground cost and holding and inventory cost of the engine
How to develop maintenance program in aviation industry with considering cost, operational aspect. Comparing MSG System, FMEA principal and commercial aspect. Airline maintenance program is ultimately important for sustainability of airline business
Aircraft Rotable Components - MRO Cost Models / SAP Preventive and Predictive...Frank A.
A rapid repair loop is a key component of an agile supply chain. It is also one of the most direct ways to save money in high-tech, high-pressure sectors. Put differently, the only way to compensate for a sub-optimized repair loop is to spend more money on new stock.
The main objective of this study is to increase the productivity against the demand. The Quality related issue regarding material&
material shortage online is not in the scope of this study. Taking a value stream perspective means working on the big picture, nota just
individual process; and not a just optimization but an actual improvement. It covers value adding as well as non-value-adding activities. This
study also includes layout improvement and time study report.
This research shows marking benefit associated with the implementation of lean program because this project shows an industrial case
study of MCCB manufacturing Assembly line.
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.
Enhancement of the performance of an industry by the application of tqm conceptseSAT Journals
Abstract Nowadays many companies are unable to prove their performance, because they do not practice the TQM concepts in- total. In order to increase the awareness, certain TQM techniques are suggested to enhance overall performance of the organisations. Here an effort is made to apply two important basic concepts of TQM which are i)continuous improvement of production process by applying newer and innovative methods ii)establishing performance measures for the processes .This paper uses the real experimental results of cartons making industry which comprises the four machines such as Printing , Punching , Gluer and Lamination machines. We get all the machines input and output details, and then made certain suggestions based on the input values of all the four machines. Presently the four machines output values such as Availability, Performance, Quality and Overall Equipment Effectiveness are very low compared with the world class industry. In order to increase them it is suggested to reduce the downtime and other non-productive time by adopting certain simple TQM techniques. The new improved values found to be much higher than the existing values. Keywords: Total Quality Management, Availability, Performance, Quality, Overall Equipment Effectiveness, Quality Improvement.
Bayesian approach for spare parts replenishment policies under uncertaintiesIJERD Editor
The legislative constraints, the need to optimize the dismantling process, the introduction of recycled
parts on the spare parts market are reinforced since the systems in end-of-life phase have become increasingly
profitable. There are few works that treat recycled spare parts integration problem in economic models of
inventory control. These works do not consider uncertainty. In order to manage more realistically the inventory
control of spare parts, we propose a probabilistic model formalized by a Bayesian network. The model is used to
identify the best purchase policy. More precisely, it allows choosing the best proportions between new spare
parts (NSP) and recycled spare parts (RSP) by taking into account the traditional criteria of inventory control
and the availability of the spare parts on the market. The proposed method provides a decision-making tool for
manufacturers who are interested both in reducing the costs of stocks and guaranteeing a minimal availability in
an uncertain environment.
For a company to continue business, the role of the Spare Parts department is very important. Whether or not the part activities are properly controlled, can greatly influence the company’s success.
The system control among other things is vitally important to the Spare Business Unit (SBU) control, for effective operation of actual SBU.
Engine Stock Control Using the concept of U curve technique, it is delivering the best solution based on Aircraft on ground cost and holding and inventory cost of the engine
How to develop maintenance program in aviation industry with considering cost, operational aspect. Comparing MSG System, FMEA principal and commercial aspect. Airline maintenance program is ultimately important for sustainability of airline business
Aircraft Rotable Components - MRO Cost Models / SAP Preventive and Predictive...Frank A.
A rapid repair loop is a key component of an agile supply chain. It is also one of the most direct ways to save money in high-tech, high-pressure sectors. Put differently, the only way to compensate for a sub-optimized repair loop is to spend more money on new stock.
Prioritization 301: An Advanced Roadmapping Class for Product PeopleUpUp Labs
Veteran Product Person Bruce McCarthy's funny and insightful presentation on how to make fanboys out of all your stakeholders by using objective criteria to prioritize your requirements and drive consensus.
As seen at ProductCamp Boston, June 2012.
Visit www.reqqs.com/resources for a Scorecard template in Excel and information on Reqqs - The Smart Roadmap Tool for Product People.
A MODEL STUDY ON COMPARATIVE COST ANALYSIS OF EQUIPMENT MANAGEMENT IN CONSTRU...IAEME Publication
Construction Equipment is the important factor to run the project in a successful manner. it is
important for both private constructions and also for Trust based organizational Construction
projects’ success. A large number of quantities of equipment are required in construction even in
small construction companies also there is a need to invest high initial cost in equipment. Nearly
40% of construction cost is related to equipment. This paper elevates the elements to be considered
while purchasing, leasing or renting the equipment, and guide in optimizing the profitability.
Methods of life cycle cost estimating and decision methods were researched and compared. Data
was acquired from equipment rental companies, private construction companies, and Trust base
organizational projects
A Proposed Fuzzy Inventory Management PolicyYogeshIJTSRD
Managing inventory under inaccurate or incomplete data considers a complex process to find the optimal policy to reduce total inventory costs. Hence, we resort in this paper to the use of the fuzzy technique to treat this deficiency in the data. This study considers important because it is hoped that on the completion, the study will extend further insights into the conception of stock control measures. Through using automotive service center as a reference point, the study will make an interesting contribution to the understanding of the general and special effects of stock control in other private and public utilities. In this paper, it will be proposed a mathematical model for optimal fuzzy inventory policy to minimize the total inventory cost by using the fuzzy assignment technique and will be applied it on a case study. El-Sayed Ellaimony | Mohamed Khalil | Ahmed Taha | Mohamed Osman "A Proposed Fuzzy Inventory Management Policy" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-3 , April 2021, URL: https://www.ijtsrd.com/papers/ijtsrd40005.pdf Paper URL: https://www.ijtsrd.com/management/operations-management/40005/a-proposed-fuzzy-inventory-management-policy/elsayed-ellaimony
Any firm typically made a large investment in a piece of capital machinery and, in theory, it could run 24 hour a day for seven days a week at its optimum Speed. If it did this you gain the maximum value from the investment. In reality there is number of element that can affect the value gained from the investment. So that fully utilization of equipment can be done. Hence for fully utilization of any equipment any firm must have to calculate OEE. This paper represents the methodology applied in increasing the OEE of an Organization by exchanging the feed mechanism from Bowl Feeder to a Conveyor.
Aggregate planning using transportation method a case study in cable industryijmvsc
Aggregate planning is an analytical tool that proposes a strategy to meet demand according to the
capacity constraints. In this paper, aggregate planning strategies are discussed and a special structure of
transportation model is investigated for the aggregate planning purpose of “Bangladesh Cable Shilpa
Ltd, Khulna”. For this transportation problem, all the unit costs, supplies, demands & other values are
taken from a case study. The forecasting demand values are determined using Single Exponential
Smoothing Forecasting technique. Transportation model & the Transportation algorithm is discussed in
this paper. A real life unbalanced transportation problem is discussed and solved to bring the most
efficient technique of reducing transportation and storage cost. Vogel Approximation Method (VAM)
algorithm is also discussed & used to determine the starting solution of the transportation model. Finally,
TORA software is used to find the optimum cost by using transportation method.
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.
The Use of Java Swing’s Components to Develop a WidgetWaqas Tariq
Widget is a kind of application provides a single service such as a map, news feed, simple clock, battery-life indicators, etc. This kind of interactive software object has been developed to facilitate user interface (UI) design. A user interface (UI) function may be implemented using different widgets with the same function. In this article, we present the widget as a platform that is generally used in various applications, such as in desktop, web browser, and mobile phone. We also describe a visual menu of Java Swing’s components that will be used to establish widget. It will assume that we have successfully compiled and run a program that uses Swing components.
3D Human Hand Posture Reconstruction Using a Single 2D ImageWaqas Tariq
Passive sensing of the 3D geometric posture of the human hand has been studied extensively over the past decade. However, these research efforts have been hampered by the computational complexity caused by inverse kinematics and 3D reconstruction. In this paper, our objective focuses on 3D hand posture estimation based on a single 2D image with aim of robotic applications. We introduce the human hand model with 27 degrees of freedom (DOFs) and analyze some of its constraints to reduce the DOFs without any significant degradation of performance. A novel algorithm to estimate the 3D hand posture from eight 2D projected feature points is proposed. Experimental results using real images confirm that our algorithm gives good estimates of the 3D hand pose. Keywords: 3D hand posture estimation; Model-based approach; Gesture recognition; human- computer interface; machine vision.
Camera as Mouse and Keyboard for Handicap Person with Troubleshooting Ability...Waqas Tariq
Camera mouse has been widely used for handicap person to interact with computer. The utmost important of the use of camera mouse is must be able to replace all roles of typical mouse and keyboard. It must be able to provide all mouse click events and keyboard functions (include all shortcut keys) when it is used by handicap person. Also, the use of camera mouse must allow users troubleshooting by themselves. Moreover, it must be able to eliminate neck fatigue effect when it is used during long period. In this paper, we propose camera mouse system with timer as left click event and blinking as right click event. Also, we modify original screen keyboard layout by add two additional buttons (button “drag/ drop” is used to do drag and drop of mouse events and another button is used to call task manager (for troubleshooting)) and change behavior of CTRL, ALT, SHIFT, and CAPS LOCK keys in order to provide shortcut keys of keyboard. Also, we develop recovery method which allows users go from camera and then come back again in order to eliminate neck fatigue effect. The experiments which involve several users have been done in our laboratory. The results show that the use of our camera mouse able to allow users do typing, left and right click events, drag and drop events, and troubleshooting without hand. By implement this system, handicap person can use computer more comfortable and reduce the dryness of eyes.
A Proposed Web Accessibility Framework for the Arab DisabledWaqas Tariq
The Web is providing unprecedented access to information and interaction for people with disabilities. This paper presents a Web accessibility framework which offers the ease of the Web accessing for the disabled Arab users and facilitates their lifelong learning as well. The proposed framework system provides the disabled Arab user with an easy means of access using their mother language so they don’t have to overcome the barrier of learning the target-spoken language. This framework is based on analyzing the web page meta-language, extracting its content and reformulating it in a suitable format for the disabled users. The basic objective of this framework is supporting the equal rights of the Arab disabled people for their access to the education and training with non disabled people. Key Words : Arabic Moon code, Arabic Sign Language, Deaf, Deaf-blind, E-learning Interactivity, Moon code, Web accessibility , Web framework , Web System, WWW.
Real Time Blinking Detection Based on Gabor FilterWaqas Tariq
New method of blinking detection is proposed. The utmost important of blinking detections method is robust against different users, noise, and also change of eye shape. In this paper, we propose blinking detections method by measuring of distance between two arcs of eye (upper part and lower part). We detect eye arcs by apply Gabor filter onto eye image. As we know that Gabor filter has advantage on image processing application since it able to extract spatial localized spectral features, such line, arch, and other shape are more easily detected. After two of eye arcs are detected, we measure the distance between both by using connected labeling method. The open eye is marked by the distance between two arcs is more than threshold and otherwise, the closed eye is marked by the distance less than threshold. The experiment result shows that our proposed method robust enough against different users, noise, and eye shape changes with perfectly accuracy.
Computer Input with Human Eyes-Only Using Two Purkinje Images Which Works in ...Waqas Tariq
A method for computer input with human eyes-only using two Purkinje images which works in a real time basis without calibration is proposed. Experimental results shows that cornea curvature can be estimated by using two light sources derived Purkinje images so that no calibration for reducing person-to-person difference of cornea curvature. It is found that the proposed system allows usersf movements of 30 degrees in roll direction and 15 degrees in pitch direction utilizing detected face attitude which is derived from the face plane consisting three feature points on the face, two eyes and nose or mouth. Also it is found that the proposed system does work in a real time basis.
Toward a More Robust Usability concept with Perceived Enjoyment in the contex...Waqas Tariq
Mobile multimedia service is relatively new but has quickly dominated people¡¯s lives, especially among young people. To explain this popularity, this study applies and modifies the Technology Acceptance Model (TAM) to propose a research model and conduct an empirical study. The goal of study is to examine the role of Perceived Enjoyment (PE) and what determinants can contribute to PE in the context of using mobile multimedia service. The result indicates that PE is influencing on Perceived Usefulness (PU) and Perceived Ease of Use (PEOU) and directly Behavior Intention (BI). Aesthetics and flow are key determinants to explain Perceived Enjoyment (PE) in mobile multimedia usage.
Collaborative Learning of Organisational KnolwedgeWaqas Tariq
This paper presents recent research into methods used in Australian Indigenous Knowledge sharing and looks at how these can support the creation of suitable collaborative envi- ronments for timely organisational learning. The protocols and practices as used today and in the past by Indigenous communities are presented and discussed in relation to their relevance to a personalised system of knowledge sharing in modern organisational cultures. This research focuses on user models, knowledge acquisition and integration of data for constructivist learning in a networked repository of or- ganisational knowledge. The data collected in the repository is searched to provide collections of up-to-date and relevant material for training in a work environment. The aim is to improve knowledge collection and sharing in a team envi- ronment. This knowledge can then be collated into a story or workflow that represents the present knowledge in the organisation.
Our research aims to propose a global approach for specification, design and verification of context awareness Human Computer Interface (HCI). This is a Model Based Design approach (MBD). This methodology describes the ubiquitous environment by ontologies. OWL is the standard used for this purpose. The specification and modeling of Human-Computer Interaction are based on Petri nets (PN). This raises the question of representation of Petri nets with XML. We use for this purpose, the standard of modeling PNML. In this paper, we propose an extension of this standard for specification, generation and verification of HCI. This extension is a methodological approach for the construction of PNML with Petri nets. The design principle uses the concept of composition of elementary structures of Petri nets as PNML Modular. The objective is to obtain a valid interface through verification of properties of elementary Petri nets represented with PNML.
Development of Sign Signal Translation System Based on Altera’s FPGA DE2 BoardWaqas Tariq
The main aim of this paper is to build a system that is capable of detecting and recognizing the hand gesture in an image captured by using a camera. The system is built based on Altera’s FPGA DE2 board, which contains a Nios II soft core processor. Image processing techniques and a simple but effective algorithm are implemented to achieve this purpose. Image processing techniques are used to smooth the image in order to ease the subsequent processes in translating the hand sign signal. The algorithm is built for translating the numerical hand sign signal and the result are displayed on the seven segment display. Altera’s Quartus II, SOPC Builder and Nios II EDS software are used to construct the system. By using SOPC Builder, the related components on the DE2 board can be interconnected easily and orderly compared to traditional method that requires lengthy source code and time consuming. Quartus II is used to compile and download the design to the DE2 board. Then, under Nios II EDS, C programming language is used to code the hand sign translation algorithm. Being able to recognize the hand sign signal from images can helps human in controlling a robot and other applications which require only a simple set of instructions provided a CMOS sensor is included in the system.
An overview on Advanced Research Works on Brain-Computer InterfaceWaqas Tariq
A brain–computer interface (BCI) is a proficient result in the research field of human- computer synergy, where direct articulation between brain and an external device occurs resulting in augmenting, assisting and repairing human cognitive. Advanced works like generating brain-computer interface switch technologies for intermittent (or asynchronous) control in natural environments or developing brain-computer interface by Fuzzy logic Systems or by implementing wavelet theory to drive its efficacies are still going on and some useful results has also been found out. The requirements to develop this brain machine interface is also growing day by day i.e. like neuropsychological rehabilitation, emotion control, etc. An overview on the control theory and some advanced works on the field of brain machine interface are shown in this paper.
Exploring the Relationship Between Mobile Phone and Senior Citizens: A Malays...Waqas Tariq
There is growing ageing phenomena with the rise of ageing population throughout the world. According to the World Health Organization (2002), the growing ageing population indicates 694 million, or 223% is expected for people aged 60 and over, since 1970 and 2025.The growth is especially significant in some advanced countries such as North America, Japan, Italy, Germany, United Kingdom and so forth. This growing older adult population has significantly impact the social-culture, lifestyle, healthcare system, economy, infrastructure and government policy of a nation. However, there are limited research studies on the perception and usage of a mobile phone and its service for senior citizens in a developing nation like Malaysia. This paper explores the relationship between mobile phones and senior citizens in Malaysia from the perspective of a developing country. We conducted an exploratory study using contextual interviews with 5 senior citizens of how they perceive their mobile phones. This paper reveals 4 interesting themes from this preliminary study, in addition to the findings of the desirable mobile requirements for local senior citizens with respect of health, safety and communication purposes. The findings of this study bring interesting insight to local telecommunication industries as a whole, and will also serve as groundwork for more in-depth study in the future.
Principles of Good Screen Design in WebsitesWaqas Tariq
Visual techniques for proper arrangement of the elements on the user screen have helped the designers to make the screen look good and attractive. Several visual techniques emphasize the arrangement and ordering of the screen elements based on particular criteria for best appearance of the screen. This paper investigates few significant visual techniques in various web user interfaces and showcases the results for better understanding and their presence.
Virtual teams are used more and more by companies and other organizations to receive benefits. They are a great way to enable teamwork in situations where people are not sitting in the same physical place at the same time. As companies seek to increase the use of virtual teams, a need exists to explore the context of these teams, the virtuality of a team and software that may help these teams working virtualy. Virtual teams have the same basic principles as traditional teams, but there is one big difference. This difference is the way the team members communicate. Instead of using the dynamics of in-office face-to-face exchange, they now rely on special communication channels enabled by modern technologies, such as e-mails, faxes, phone calls and teleconferences, virtual meetings etc. This is why this paper is focused on the issues regarding virtual teams, and how these teams are created and progressing in Albania.
Cognitive Approach Towards the Maintenance of Web-Sites Through Quality Evalu...Waqas Tariq
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Periodic Review Model for Determining Inventory Policy for Aircraft Consumable Spare Parts
1. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 41
Periodic Review Model for Determining Inventory Policy for
Aircraft Consumable Spare Parts
Azizah Aisyati aisyati@yahoo.com
Department of Industrial Engineering
Sebelas Maret University
Jl. Ir Sutami 36A, Surakarta, Indonesia
Wakhid Ahmad Jauhari wachid_aj@yahoo.com
Department of Industrial Engineering
Sebelas Maret University
Jl. Ir Sutami 36A, Surakarta, Indonesia
Cucuk Nur Rosyidi cak_cuk@yahoo.com
Department of Industrial Engineering
Sebelas Maret University
Jl. Ir Sutami 36A, Surakarta, Indonesia
Abstract
This research is conducted to develop inventory policy of aircraft consumable spare parts which
are needed on aircraft maintenance activity. In this research, we used periodic review model to
determine the optimal policy of aircraft spare parts inventory. By using the periodic review model,
we find optimal period of inventory review and maximum level of inventory. The optimal decision
is determined based on the minimum total cost. We have classified consumable spare parts using
ABC method to categorize them based on their dollar contribution and demand frequency.
Therefore in this research, we focus on managing the inventory level for spare parts on class C.
The result from this study shows that the proposed periodic review policy result in lower total
inventory cost compared the the company policy. The proposed policy gives an average saving
35.38 %.
Keywords: Inventory, Spare Part, Periodic Review, ABC Method.
1. INTRODUCTION
Inventory management is one of key success factors that should be considered by manager to
win the business in global competition. In modern business environment, the company needs
more significant efforts to reduce the operating cost and also increase customer satisfaction.
Inventory has significant role to satisfy the customer demand hence, it becomes important asset
for any organization. Therefore, it should be managed effectively and efficiently to minimize total
cost and to satisfy the customer’s requirement. In any real condition, inventory management
faces barriers in the form of a tradeoff between minimizing total cost and maximizing service
level. Therefore, choosing the correct inventory policy that can be applied in industry now
becomes essential to management as there are many inventory policies developed by many
scholars.
Maintenance plays an important role in airline industries. The aircraft operational daily activities
can be affected by the performance of maintenance. Moreover, the performance of maintenance
activities can be determined by how the management can provide spare part continuously during
maintenance activity. One of the largest aircraft’s MRO company in Indonesia is Garuda
Maintenance Facility Aero Asia (GMF). GMF is a company that provides maintenance, repair and
2. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 42
overhaul (MRO) service to airline industries. In this company, maintenance is known as the
activity to maintain aircraft which consist of line maintenance, base maintenance and engine
maintenance while repair is an activity to improve the broken components in aircraft machine.
Further, overhaul is an activity to monitor and give major repair to any object in aircraft, including
machine or component.
In aircraft industry, spare parts usually can be classified into three categories. First, rotable spare
part is the category of spare part that can be rotated among any types of aircraft. Second,
repairable spare part is spare parts that have a same character as rotable spare part but having
lower price.Third, consumable spare part is the spare parts that can be used once or disposable
component. In this research, we focus on managing consumable spare parts due to their
magnitude needs in daily MRO activity. Consumable spare parts have higher demand than other
spare parts and should be purchased from foreign countries, hence, the replenishment lead time
may take a long time. If the spare parts aren’t well managed by management, the daily MRO
process will probably be interrupted due to the lack of spare part inventories. Moreover, if
management decides to hold more spare parts to guarantee that the needs from daily MRO
activity must be satisfied, a high inventory cost may occurs. Therefore, controlling consumable
spare part accurately is needed by management to ensure that the daily MRO activities run
smoothly.
Some researchers focused on developing inventory model based on deterministic environment.
Croston [1], Syntetos and Boylan [3], Syntetos and Boylan [4], Syntetos and Boylan [5] proposed
deterministic inventory model for spare parts which considering some forecasting methods. The
demand of spare parts are forecasted and then the optimal inventory level can be determined by
some formulas.
Strijbosch et al [6] developed another model compound bernoulli method and compound poisson
method to determine ordering quantity and reorder point. Teunter and Sani [7] gave their
research attention on studying the lumpy product. They used order-up-to policy to determine
inventory level which previously employed croston method to forecast the demand. Results from
this research indicated that integrating croston method and order-up-to policy results in optimal
service level. Chang et al [8] implemented r,r,Q policy to manage semiconductor component by
assuming stochastic demand. Furthermore, Porras and Dekker [9] determined spare part
inventory level at oil company. They used different reorder points to find optimal inventory level in
order to minimize total inventory cost. Smidth-Destombes et al. [10] proposed joint optimization of
inventory management and maintenance activity. They proposed a heuristic model to derive the
optimal solutions and proved that the proposed model performed better than METRIC model.
Kilpi et al.[11] developed cooperative strategies for the availability service of repairable aircraft
components and determined the factors that give the contribution to the cooperative strategy.
They used simulation model to determine optimal cost and used game theory to test the
cooperative strategies. Wong et al. [12] investigated the cost allocation problem in context of
repairable spare parts pooling with game theoretic model. The results from this study showed that
the cost allocation policy affects the companies in making the decision in inventory management.
Even many methods have been implemented in determining spare part inventory level, lack of
them considering the utilization of continuous review model in reducing total inventory cost.
In this paper we intend to determine spare part inventory level in order to minimize total inventory
cost. In this research, we use periodic review policy to determine optimal periodic review and
safety stock. The results from many studies proved that periodic review policy can be applied
more easily in managing inventory than continuous review policy. This is because using periodic
review, the company has less effort on reviewing the inventory level, hence some costs such as
information system cost, labor cost can be significantly reduced. Here, we also intend to continue
the work of Aisyati, et al. [13] by proposing periodic review as a policy to manage the spare parts
in Class C. Previously, Aisyati, et al [13] used ABC classification system to categorize spare part
based on their contribution to dollar volume. They focused on determining the optimal inventory
3. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 43
level on Class A and B by using continuous review model. Periodic review policy review is
popular method which is very useful and easy method to implement in many areas of industries.
2. LITERATURE REVIEW
2.1 Periodic Review Model
The periodic review model is one of the inventory policies that reviews physical inventory at
specific interval of time and orders the quantity order as many as the maximum level of inventory
Wisner, et al [14]. The safety stock of periodic review model is larger than that of continuous
review model. This safety stock is important to meet demand at lead time period (L). One of
Periodic Review Model is P model. This model characterize fixed order interval (T) and the
quantity order based on the differ of the maximum inventory level (R) and the on hand inventory.
We can draw this situation in Figure 1.
Figure 1. P Model Inventory (Bahagia, [15]).
In this model, the total cost inventory (OT) is consist of ordering cost, ordering cost, holding cost,
dan shortage cost [14].
The ordering cost (Op ) can be determined by multiplying cost of each order(A) and order
frequency per year (f). For order in interval T, the order frequency per year is 1/T. Therefore the
ordering cost can be formulated as :
ܱ =
A
T
………………………………………………………………………………....(1)
The holding cost per unit time (Os ) is determined by multiplying the expected of inventory per
year (m) and holding cost per unit product per year (h). In a cycle, the inventory will be at the level
(s + TD) at the beginning of the cycle and at the level (s) at the end of the cycle, so the expected
of inventory is:
݉ = s +
TD
2
…………………………………………………………………………..(2)
In case of shortage, inventory backorder can be met then. The backorder allow negative values
so the expected value of s is:
s = නሺR-zሻfሺzሻ
ஶ
0
dz
= R- න zfሺzሻ
ஶ
0
dz
4. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 44
If zfሺzሻ
∞
0
dz = DሺL + Tሻ
= DL + TD
so,
s = R – DL – TD ………………………………………………………………… (3)
where,
z : Random variable of demand for (T + L) period
f(z) : Probability function of demand z
DL : Expected of demand for L period
T : Interarrival demand
So, the expected of inventory (m) is :
݉ = R - DL - TD +
TD
2
݉ = R - DL -
TD
2
………………………………………………………………… (4)
By subtituting equation (4) into Os, holding cost (Os) can be expressed as :
Os = ൬R-DL-
TD
2
൰ h……………………………………………………………(5)
Shortage can be happened when demand fluctuation is occurred in (T+L) periods. Like Q model,
shortage cost can be calculated based on the number of stock out. For one year, shortage cost
(Ok) can be formulated as follow:
Ok = NTcu …………………………………………………………………………(6)
NT can be defined by multiplying the number of cycle per year and the number of stock out in a
cycle. NT is as follow:
NT = N ×
1
T
=
N
T
……………………………………………………………………………….(7)
Therefore, the shortage cost can be expressed as :
Ok =
cuN
T
……………………………..……………………….. …………………...(8)
5. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 45
If backorder is permitted to solve shortage problem, then we can substitute equation (1) until (8)
to OT as follow Bahagia [15]:
OT = Op + Os + Ok
OT = DP +
A
T
+ h ൬R-DL+
DT
2
൰ +
cu
T
නሺz-Rሻfሺzሻ
∞
R
dz………...……….……………………...(9)
Decision variable T and R can be found by taking the first partial derivatives of OT with respect to
T and R respectively and equating them to zero.
∂OT
∂T
= 0
=
A
ܶ2
+
1
2
hD
cu
ܶ2
නሺz-Rሻfሺzሻ
∞
R
dz = 0
T∗
= ඨ
2ൣA+cu ሺz-Rሻfሺzሻ
∞
R
dz൧
hD
……...……….………………………………………...…...(10)
∂OT
∂R
= 0
= h-
cu
T
න fሺzሻ
∞
r
dz = 0
α = න fሺzሻ
∞
r
dz =
Th
cu
……...……….…………………………….……….………..(11)
Equation (10) and (11) is implicit function, so the optimal solution can not be found analytically.
Considering the iterative procedure from Hadley-Within Method, the algorithm to solve the
periodic review is as follows:
a. Find value of T
T =ඨ
2A
Dh
b. Find α and R value by using equation (11).
ߙ =
Th
cu
If demand has normal distribution, R value will be including demand in (T+L) period and
can be expressed as :
R = D(T + L) + zα √ܶ + ܮ
6. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 46
c. Find the (OT)0 value by using equation (9).
d. Repeat step b by changing T0 = T0 + ∆T0
• If new (OT)0 > (OT)0 , then stop to increase T0. Next, we try decrease iteration (T0 = T0
- ∆T0) until we find T
*
= T0 that result minimum value of OT
*
.
• If new (OT)0 < (OT)0 , increasing iteration (T0 = T0 + ∆T0) can be continued and can
be stopped when new (OT)0 > (OT)0 . The value of T0 that result minimum total cost
(OT
*
) is an optimal interval time (T
*
)
3. RESEARCH METHODOLOGY
In first stage of our research we define spare parts class C from classification to categorize 60
consumable spare parts [13] There are 36 spare parts in class C presented in Table 1. Secondly,
we find all input parameters of spare parts including, the mean of demand per unit time, standard
deviation of demand and inventory cost, including holding cost, ordering cost and shortage cost.
The mean and standard deviation of demand for selected spare parts is determined from demand
data during ten years. Holding cost is determined by considering interarrival demand, expected
demand and maximum level of inventory. Shortage cost is determined from the number of cycle
per year and the number of stock out in a cycle. The ordering cost is determined by considering
cost of each order(A) and order frequency per year. Table 1 presents the input parameters and
inventory cost of 36 spare parts studied in this research. The final stage of this research, we
determine the optimal interval period and maximum level of inventory by using Hadley-Within
algorithm described in previous section.
FIGURE 2: Research Methodology.
Define spare parts
Determining mean and
standard deviation of
selected spare parts
Determining ordering cost,
holding cost and shortage
cost
Determining optimal value
of interval time and
maximum level of
inventory
8. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 48
4. RESULTS AND DISCUSSIONS
4.1 Input Parameters
In this research, we focus to manage the spare part inventory in class C which consists of 36
spare parts. We can define spare parts in class C in Table 1. From Table 1 we know spare part
4551 have the largest mean and standard deviation of demand. This shows that the spare part is
the most needed spare part.
4.2 Determination of Interval Review Period and Maximum Level of Inventory
Interval period (T) and maximum level of inventory (R) are determined by employing an iterative
procedure described in above section. We develop list of program using MATLAB 2009a. The
results from MATLAB program are given in table 2. From this table we can see that there are
different values of review period for each spare part. Spare parts BV03112-03-33 and 69-41868-3
have the longest review period that is 2.57 year and 2.48 year. Further, spare part 1683 has the
shortest review period (0.0893 year). From table 1 we also can see that the maximum inventory
levels are determined in a range of 2-285 units. The demand rate is the factor that affecting the
quantity of inventory level.
No Spare Part
Review
Period
(year)
Review
Period
(month)
Maximum
Inventory
(unit)
Total Cost of
Periodic Review
(IDR)
1 ABS0368-01 0.9744
12
228 5,142,200
2 BV03112-03-33 2.5725
31
285 19,366,000
3 2315M20-3 1.9
23
83 7,107,700
4 ASPF-S-V06 0.94
11
81 2,198,200
5 65-90305-17 1.08
13
25 1,730,400
6 QD1004-125 1.424
17
90 3,377,300
7 69-41868-3 2.489
30
162 13,096,000
8 CA00075A 0.8
10
55 1,584,000
9 FK20159 1.889
23
82 4,132,000
10 77870949 0.9097
11
7 445,380
11 65-90305-59 0.7354
9
58 1,543,000
12 BACH20X3 0.9026
11
7 1,789,800
13 QA06123 0.8364
10
10 403,730
14 332A1034-25 0.4887
6
3 645,010
15 RG1969 0.7752
9
6 269,840
16 65C27738-2 0.3443
4
2 270,660
17 OF25-021 0.7625
9
9 366,350
18 BACC63BV14B7SN 0.9142
11
30 1,294,200
19 FK20158 0.8938
11
13 64,536
20 BACR15BB6D7C 0.8107
10
15 58,386
21 MS29526-2 0.7031
8
10 35,251
22 BACB30NN4K4 0.2551
3
44 853,100
23 ABS0367-030 0.7285
9
32 863,700
24 ABS0604-4 0.2926
4
62 773,190
25 F5746293620100 0.3738
4
6 160,220
26 BACR15GF8D7 0.9
11
4 241,170
10. Azizah Aisyati, Wakhid Ahmad Jauhari & Cucuk Nur Rosyidi
International Journal of Business Research & Management (IJBRM), Volume (5) : Issue (3) : 2014 50
28 MS29513-334 428,290 1,210,700 782,410 64.62
29 S9413-111 431,380 1,616,694 1,185,314 73.32
30 BACN10JC4CD 301,770 954,375 652,605 68.38
31 65B10920-171 666,630 114,158 -552,472 -483.95
32 4551 667,420 5,671,358 5,003,938 88.23
33 1683 507,850 3,876,801 3,368,951 86.90
34 M83248/1-906 69,685 218,092 148,407 68.05
35 BACB30VF4K12 111,090 371,344 260,254 70.08
36 BACW10BP41CD 480,040 1,511,333 1,031,293 68.24
TABLE 3: The Comparison of Proposed Policy and Company Policy.
Table 3 shows the benefit of the proposed method in comparison with company policy. The
company makes inventory policy that each spare part must be reviewed in same period (three
months). Even this policy can be done easily since the manager only has less effort to control the
inventory level of all spare parts, this policy may result in not optimal cost. This is because each
spare part has different parameters, then the optimal review period and maximum inventory
should be determined individually. From this table, one can see that when comparing with
company policy, the proposed method which adopting periodic review policy can produce
significant amount of saving in average of 35.38%. The largest saving (92.43%) is produced from
spare part BACR15BB6D7C. It is also found that there is one spare part which has negative
saving, that is spare part 65B10920-171. Moving the policy from company’s policy to proposed
policy will reduce the total inventory cost for about IDR 68,091,840 for all spare parts.
5. CONCLUSIONS
In this paper, we focus on determining the optimal review period and maximum inventory level for
consumable spare parts by employing periodic review policy. We continue the study of Aisyati et
al. (2013) by investigating the optimal inventory level for 36 spare parts in Class C. The results
from this study indicate that the periodic review will produce lower total inventory cost compared
to the company policy. Moreover, moving from company’s policy to the proposed policy will also
result significant amount of saving on average 35.38%. However, one spare part that is spare
part 65B10920-171 still produce negative saving, hence further comprehensive investigation
should be done to it.
Further study can be done by introducing another demand’s distribution, such as poisson demand
or compound poisson demand. This kind of distribution may be suitable with the spare part
demand since it is usually modeled as intermittent demand. Another extension can be done by
integrating the inventory policy into maintenance activity. Previously, most of maintenance
models discuss only maintenance activity and neglecting its relationship with spare part inventory.
Integrating both policies in one model may produce some important insights.
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