| 1. |
- A Asif, Farazee M, 1980-, et al.
(författare)
-
Performance analysis of the closed loop supply chain
- 2012
-
Ingår i: Journal of Remanufacturing. - Germany : Springer Science and Business Media LLC. - 2210-4690. ; 2:4
-
Tidskriftsartikel (refereegranskat)abstract
- PurposeThe question of resource scarcity and emerging pressure of environmental legislations has brought a new challenge for the manufacturing industry. On the one hand, there is a huge population that demands a large quantity of commodities; on the other hand, these demands have to be met by minimum resources and pollution. Resource conservative manufacturing (ResCoM) is a proposed holistic concept to manage these challenges. The successful implementation of this concept requires cross functional collaboration among relevant fields, and among them, closed loop supply chain is an essential domain. The paper aims to highlight some misconceptions concerning the closed loop supply chain, to discuss different challenges, and in addition, to show how the proposed concept deals with those challenges through analysis of key performance indicators (KPI).MethodsThe work presented in this paper is mainly based on the literature review. The analysis of performance of the closed loop supply chain is done using system dynamics, and the Stella software has been used to do the simulation. Findings The results of the simulation depict that in ResCoM; the performance of the closed loop supply chain is much enhanced in terms of supply, demand, and other uncertainties involved. The results may particularly be interesting for industries involved in remanufacturing, researchers in the field of closed loop supply chain, and other relevant areas. Originality The paper presented a novel research concept called ResCoM which is supported by system dynamics models of the closed loop supply chain to demonstrate the behavior of KPI in the closed loop supply chain.
|
|
| 2. |
- Abdullah Asif, Farazee Mohammad, 1980-, et al.
(författare)
-
METHODS ANALYSIS OF REMANUFACTURING OPTIONS FOR REPEATED LIFECYCLE OF STARTERS AND ALTERNATORS
- 2010
-
Ingår i: 7th International DAAAM Baltic Conference"INDUSTRIAL ENGINEERING"22-24 April 2010, Tallinn, Estonia. - Estonia : Tallinn University of Technology. ; , s. 340-345
-
Konferensbidrag (refereegranskat)abstract
- The Design for Repeatedly Utilization (DFRU) is a proposed conceptto be used in the product realizationprocess to ensure optimum useable life (forinstance in terms of economy, resourceusage, environmental impact etc.) ofproducts or parts of products enablingmultiple lifecycle. In the DFRU approachproducts are restored as new like productsthrough remanufacturing processes. Theterm remanufacturing has been interpreteddifferently by different researchers and theindustries that are involved inremanufacturing business use differentapproaches to remanufacture theirproducts. In this paper the starter motorand alternator of automotives has beenused to demonstrate the novel concepts.The purpose of this paper is to expresswhat remanufacturing means in ourconcept, model their major lifecycleaspects and create a simulation modelfrom it. This is a preliminary work towardsdefining and specifying the processes,methods and design properties in DFRU.The work will be further extended to aholistic business model which can facilitateDFRU approach in an efficient way. Infuture the model will be developed andadopted to create new models for otherproducts appropriate for remanufacturingand eventually DFRU.
|
|
| 3. |
- Abdullah Asif, Farazee Mohammad, 1980-, et al.
(författare)
-
Minimizing Uncertainty Involved in Designing the Closed-loop Supply Network for Multiple-lifecycle of Products
- 2010
-
Ingår i: Annals Of DAAAM for 2010 & Proceedings of 21st DAAAM Symposium. - Zadar : DAAAM International. ; , s. 1055-1056
-
Konferensbidrag (refereegranskat)abstract
- To ensure multiple-lifecycle of products through remanufacturing intervention requires a well-functioning closed-loop supply network. Generally, the unpredictability of quantity, timing and quality (physical/functional) of the returned products and demand fluctuation of the remanufactured products are the main sources of uncertainty of closed-loop supply network. To some extent, efficient recollection strategies and separate distribution channels for remanufactured products can minimize the uncertainty. Nevertheless, efficient recollection does not necessarily close the loop if the recovered products do not enter into the main stream of the supply network. Beside, products that are distributed through separate channels create an open loop. Thus, the problem of uncertainty remains unsolved. The aim of this paper is to propose solutions to minimize the uncertainty involved in designing a well-functioning closed-loop supply network using the system dynamics principle and tool.
|
|
| 4. |
- Abdullah Asif, Farazee Mohammad, 1980-
(författare)
-
Resource Conservative Manufacturing : New Generation of Manufacturing
- 2011
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The question of resource scarcity and emerging pressure of environmentallegislations have put the manufacturing industry with a new challenge. On theone side, there is a huge population that demands a large quantity ofcommodities, on the other side, these demands have to be met by minimumresources and with permissible pollution that the earth’s ecosystem can handle.In this situation, technologic breakthrough that can offer alternative resourceshas become essential. Unfortunately, breakthroughs do not follow any rule ofthumb and while waiting for a miracle, the manufacturing industry has to findways to conserve resources. Within this research the anatomy of a large body ofknowledge has been performed to find the best available practices for resourceconservation. Critical review of the research revealed that none of the availablesolutions are compatible with the level of resource conservation desired by themanufacturing industry or by society. It has also been discovered that a largegap exists between the solutions perceived by the scientists and theapplicability of those solutions. Through careful evaluation of the state-of-theart,the research presented in this thesis introduced a solution of maximizingresource conservation i.e., material, energy and value added, as used inmanufacturing. The solutions emerged from the novel concept named asResource Conservative Manufacturing, which is built upon the concept ofMultiple Lifecycle of product. Unlike other research work, the researchdocumented in this thesis started with the identification of the problem andfrom which a ‘wish to do’ list was drawn. The seriousness of the problem andpotential of adopting the proposed concept has been justified with concreteinformation. A great number of arguments have been presented to show theexisting gaps in the research and from that, a set of solutions to conserveresources has been proposed. Finally, one of the prime hypotheses concerningclosed loop supply chain has been validated through the system dynamicsmodeling and simulation.
|
|
| 5. |
- Adane, Tigist Fetene, et al.
(författare)
-
System dynamics analysis of energy usage : Case studies in automotive manufacturing
- 2012
-
Ingår i: SPS12 conference proceedings. ; , s. 1-9
-
Konferensbidrag (refereegranskat)abstract
- Our life is strongly linked with the usage of natural resources. Energy is a necessity in everyday life and is often generated using non-renewable natural resources which are finite. Energy consumption in manufacturing industry is increasing and the way it is consumed is not sustainable. There is great concern about minimizing consumption of energy in manufacturing industry to sustain the natural carrying capacity of the ecosystem. This is one of the challenges in today’s industrial world.In this paper two case studies have been carried out in crankshaft machining and cylinder head casting processes. The outcome of this research enables the company to identify potential avenues to optimize energy usage and offers a decision support tool.
|
|
| 6. |
- Adane, Tigist Fetene, et al.
(författare)
-
System dynamics analysis of energy usage: Case studies in automotive manufacturing
- 2014
-
Ingår i: International Journal of Manufacturing Research. - 1750-0591 .- 1750-0605. ; 9:2, s. 131-156
-
Tidskriftsartikel (refereegranskat)abstract
- Our life is strongly linked with the usage of natural resources. With increase in world population and welfare there is an increasing global demand for raw material. Energy is a necessity in everyday life and is often generated using non-renewable natural resources which are finite. Manufacturing is one of the largest energy and material resource consumers. There is great concern about minimising consumption of energy in manufacturing industry to sustain the natural carrying capacity of the ecosystem. This is one of the challenges in today’s industrial world. The paper presents the application of system dynamics theory for modelling and simulation of complex manufacturing processes. The simulations help to understand the intricate nature of the interrelation of process parameter and to make sound decision about minimising the energy losses. Two case studies are presented, one in cylinder head casting processes and the other in crankshaft machining. The developed models provide an insight into how to select critical operations and to identify the effect of various parameters on the energy consumption. Also, the models help to understand how changes of parameters over time affect the behaviour of energy changes. The outcome of this research enables the company to identify potential avenues to minimise energy usage and offers a decision support tool.
|
|
| 7. |
- Alazar, Abebayehu Seifu, et al.
(författare)
-
Development of cutting force measurement system used in gear hobbing
- 2011
-
Ingår i: Proceedings Of The ASME International Design Engineering Technical Conferences And Computers And Information In Engineering Conference, 2011, Vol 8. - : ASME Press. - 9780791854853 ; , s. 47-52
-
Konferensbidrag (refereegranskat)abstract
- Increasing demands for high quality and high performance gear manufacturing are reflected in a need for a model based investigation of gear hobbing process. This paper presents the development of a system for online measurement of actual cutting force components during gear hobbing. Although there are a large number of well developed cutting force measuring systems for different machining operations available in the market, it is difficult to find a system tailored to the requirements of a gear hobbing process. Hence, a fixture containing piezoelectric dynamometer and telemetry device is developed. The fixture is designed taking the real machining circumstances into consideration. The telemetry system enables wireless measurement of cutting force while machining. Multiphysics finite element analysis and Artificial Neural Network (ANN) are used as tools for modeling, simulation, and calibration of the developed system. Final stage of this work includes conducting hobbing experiments to validate both the model and the force measurement system.
|
|
| 8. |
- Archenti, Andreas, 1973-
(författare)
-
A Computational Framework for Control of Machining System Capability : From Formulation to Implementation
- 2011
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Comprehensive knowledge and information about the static and dynamic behaviour of machine tools, cutting processes and their interaction is essential for machining system design, simulation, control and robust operation in safe conditions. The very complex system of a machine tool, fixture and cutting tools during the machining of a part is almost impossible to model analytically with sufficient accuracy. In combination with increasing demands for precision and efficiency in machining call for new control strategies for machining systems. These strategies need to be based on the identification of the static and dynamic stability under both the operational and off-operational conditions. To achieve this it is necessary to monitor and analyze the real system at the factory floor in full production. Design information and operational data can then be linked together to make a realistic digital model of a given machining system. Information from such a model can then be used as input in machining simulation software to find the root causes of instability. The work presented in this thesis deals with the static and dynamic capability of machining systems. The main focus is on the operational stability of the machining system and structural behaviour of only the machine tool, as well. When the accuracy of a machining system is measured by traditional techniques, effects from neither the static stiffness nor the cutting process are taken into account. This limits the applicability of these techniques for realistic evaluation of a machining system’s accuracy. The research presented in this thesis takes a different approach by introducing the concept of operational dynamic parameters. The concept of operational dynamic parameters entails an interaction between the structural elements of the machining systems and the process parameters. According to this concept, the absolute criterion of damping is used to evaluate the dynamic behaviour of a machining system. In contrast to the traditional theory, this methodology allows to determine the machining system's dynamic stability, in real time under operating conditions. This framework also includes an evaluation of the static deformations of a machine tool. In this context, a novel concept of elastically linked system is introduced to account for the representation of the cutting force trough an elastic link that closes the force loop. In addition to the elastic link which behaves as a static element, a dynamic non-contact link has been introduced. The purpose is to study the non-linear effects introduced by variations of contact conditions in joints due to rotational speed.
|
|
| 9. |
- Archenti, Andreas, 1973-, et al.
(författare)
-
A new method for circular testing of machine tools under loaded condition
- 2012
-
Ingår i: Fifth CIRP Conference On High Performance Cutting 2012. - : Elsevier. ; , s. 575-580
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a novel test device for the evaluation of the accuracy of machine tools. The design concept is similar to a double ball bar (DBB) with the difference that an adjustable load generated by the device can be applied between spindle nose and machine tool table. The device, called Loaded Double Ball Bar (LDBB), can be used either as an ordinary double ball bar system with no load applied to the structure, or with a predefined load applied to the structure. The load that is generated by the LDBB is generally not equivalent to real cutting forces. However, from the static deflection point of view the effect of the load on the machine tool structure has similar impact on the static behaviour of the system. For instance, the load can in some cases eliminate existing play in ball screws, plays that under normal machining condition will be eliminated by the effect of cutting forces on the structure. With the help of this test device, not only can the identifiable errors by an ordinary DBB be evaluated but also machine tool elastic deflection in different directions. It is also possible to track different error patterns to the applied load.
|
|
| 10. |
- Archenti, Andreas, 1973-, et al.
(författare)
-
Accuracy analysis of machine tools using Elastically Linked Systems
- 2013
-
Ingår i: CIRP annals. - : Elsevier. - 0007-8506 .- 1726-0604. ; 62:1, s. 503-506
-
Tidskriftsartikel (refereegranskat)abstract
- The paper introduces the concept of Elastically Linked Systems (ELS) to directly relate the machine tool positional and static accuracy to the machined part’s geometric errors and form deviation. Practical implementation of the ELS concept resulted in a novel test equipment, Loaded Double Ball Bar (LDBB) which is a precision mechatronic device with variable load. The test method based on the device is able to reveal machine tool characteristics not obtainable with existing methods as for instance the variation of stiffness in the entire working space. The LDBB is used to experimentally evaluate the stiffness and the corresponding accuracy of five machine tools.
|
|
