Emre Cevikcan

Fuzzy rule-based system for the economic analysis of RFID investments

Radio frequency identification (RFID) technology introduces the opportunity for increased visibility by facilitating easy tracking and identifying of goods, assets and even living things. The number of RFID applications and users in various fields are growing. However, high investment cost and inadequate technical capability still remain as challenges for RFID system implementations. That being the case, fair evaluation of savings associated with increasing performance and investment costs has a great role in the success of RFID projects. In this study, a systematic framework for the economic analysis for RFID investment is proposed. In this method, the elements of cost and benefits are determined in order to measure the value of an RFID investment. The expected increase of customer order is determined in terms of delivery accuracy and delivery time via a fuzzy rule-based system. The Monte-Carlo simulation method is used to determine the expected net present value (NPV) of RFID investment. A case study is constructed on the basis of expert conception to illustrate the proposed method.

A team-oriented design methodology for mixed model assembly systems

Team-oriented approaches are widely being used in modern real life assembly systems, as are other modern systems. In this paper, first the literature of single and mixed model assembly line balancing, which plays an important role for the design of assembly systems, is reviewed. The associated literature matrixes reveal that team-oriented approaches do not have an intensive research area. Second, a team-oriented mathematical programming model for creating assembly teams (physical stations) in mixed model assembly lines is devised. Owing to the fact that this model is NP hard, a scheduling based heuristic algorithm is developed. The mixed model assembly line design methodology, which includes a team-oriented algorithm as a step, is proposed. Both model sequencing and worker transfer systems are included in the methodology. The algorithms for each step of the methodology are also coded by using MATLAB and MS Excel is used as the user interface. Furthermore, the presented methodology was applied in a chosen segment of a real life mixed model tractor assembly system.

Intelligence decision systems in enterprise information management

Purpose – The purpose of this paper is to show how intelligence techniques have been used in information management systems.Design/methodology/approach – The results of a literature review on intelligence decision systems used in enterprise information management are analyzed. The intelligence techniques used in enterprise information management are briefly summarized.Findings – Intelligence techniques are rapidly emerging as new tools in information management systems. Especially, intelligence techniques can be used to utilize the decision process of enterprises information management. These techniques can increase sensitiveness, flexibility and accuracy of information management systems. The hybrid systems that contain two or more intelligence techniques will be more used in the future.Originality/value – The intelligence decision systems are briefly introduced and then a literature review is given to show how intelligence techniques have been used in information management systems.

VEHICLE ROUTE OPTIMIZATION FOR RFID INTEGRATED WASTE COLLECTION SYSTEM

Radio Frequency IDentification (RFID) technology has been in use for several decades to track and identify goods, assets, and even living things. Recently, however, RFID has generated widespread corporate interest as a means to waste management performance. In this paper, a vehicle routing model for waste collection is developed. The model not only uses precise data with respect to both quantity and location via RFID technology, but also includes single vehicle with a pre-determined capacity, multiple tours, and locations with deterministic waste quantities. Then a numerical example is solved via Dash Optimization XPress Solver to find an optimal route considering the locations of waste bins and the waste quantities. The impact of changing waste quantity on the operation cost is investigated considering the distance of the waste bins using variance analysis (ANOVA). With this method, municipality authorities can better manage itineraries and manpower, and have a monitoring system for the volume of the waste produced in the region of their responsibility.

A mathematical programming approach for walking-worker assembly systems

Purpose – It has become increasingly critical to design and maintain flexible and rapid assembly systems due to unpredictable and varying market conditions. The first stage of developing such systems is to restructure the existing assembly system. After designing the manufacturing system, efforts should be made for capacity adjustments to meet the demand in terms of allocating tasks to workers. Walking-worker assembly systems can be regarded as an effective method to achieve flexibility and agility via rabbit chase (RC) approach in which workers follow each other around the assembly cell or line and perform each task in sequence. In this paper, a novel mathematical programming approach is developed with the aim of integrating RC in assembly processes. Therefore, this study is thought to add value to industrial assembly systems in terms of effectively raising engineering control for task allocation activities. Design/methodology/approach – Two consecutive mathematical models are developed, since such a hie...

Integrating parts design characteristics and scheduling on parallel machines

Setup times have an important effect on providing quick response to the external besides internal customers. As well as eliminating setup activities, jobs with sequence-dependent setup times should be scheduled efficiently so as to reduce setup times. In this paper, a scheduling methodology which considers parts design characteristics is presented for parallel machines. With respect to the roadmap of the methodology, a parts design characteristics based scheduling algorithm is developed in order to reduce total setup times. When evaluating the performance of sequencing methods, the cable cutting-stripping-crimping (CSC) process of a real life wiring harness production system is focused. In the current scheduling system of CSC division, cable sequences are developed semi-manually by CSC supervisors. Making the proposed methodology compatible with cable sequencing, an expert system is developed so as to reduce the burden of supervisors and improve effectiveness. Performance comparison of scheduling algorithms is based on deviation from the lower bound for the total setup time as well as previously implemented semi-manual cable sequences. With respect to performance comparison, parts design characteristics based scheduling algorithm has resulted in 6.81% reduction of the total setup time compared to implemented semi-manual cable sequences (MCS) for 45-day production data.

An integrated job release and scheduling approach on parallel machines

We integrate the mathematical programming models of JR with job scheduling.We present a methodology which integrates JR and job scheduling on parallel machines.Application of the methodology in electric wire-harness industry through VSM. This paper presents a new job release (JR) and scheduling methodology for one-stage parallel machines where sequence dependent setup times exist. A decision support system (DSS) based on job release is developed in order to enable the application of the methodology. First, mathematical programming models for both job release and job scheduling are devised. Then, due to the NP-hard nature of the problems, heuristics are proposed. As for the interaction between JR and scheduling, job scheduling is integrated with job release for the proposed heuristic solutions so that the capacity achievement provided by scheduling can be utilized for job release. In brief, product design characteristics oriented scheduling affects JR in the proposed approach. Moreover, value stream mapping (VSM) approach is used with the aim of stating the effect of the proposed methodology. Furthermore, the presented methodology was applied in a real life electric wire-harness production system. The application, based on 120-day production data, revealed that the proposed methodology provided 25% decrease in in-plant manufacturing lead time.

Assessment of Energy Efficiency in Lean Transformation: A Simulation Based Improvement Methodology

The philosophy of Lean Manufacturing is to do more with less by eliminating non-value-added activities from production process. Lean manufacturing has several tools to improve lead time, cost, and quality performance as well as flexibility of systems. Therefore, the application level of Lean Manufacturing has gone through a significant evolution from shop floor to supply chain. Furthermore, Lean Manufacturing tools lead to significant effect on energy efficiency which is a vital factor for competitive advantage and environment preservation. In this chapter, a simulation-based generic framework is provided for the assessment of energy efficiency in Lean Manufacturing systems with the aim of providing contribution to the theoretical and practical studies addressing both sustainable energy and performance in manufacturing systems. Reflecting hierarchical nature of manufacturing systems, the proposed framework is illustrated in detail.

Minimising utility work and utility worker transfers for a mixed-model assembly line

Mixed-model assembly lines (MMALs) are types of production lines that are able to respond to diversified costumers’ demand for a variety of models without holding large inventories. The effective utilisation of a mixed-model assembly line requires the determination of the assembly sequence for different models. In this paper, two objectives are considered in a sequential manner, namely minimising: (i) total utility work, which means work from an additional worker to assist an operator for completion of an assembly task; and (ii) utility worker transfer which states the move of a utility worker to a different segment of the assembly line. First, due to the NP-hard nature of the problem, three heuristic methods are proposed with the aim of minimising total utility work. Then, the solutions which are obtained from the heuristics are improved in terms of the total number of utility worker transfers via a local search based method. Furthermore, the solution approach was applied in a real life mixed model tractor assembly line. Results validated the effectiveness of sequencing approach in terms of solution quality.

A Conceptual Framework for Economic Analysis of REID Reverse Logistics via Simulation

Radio frequency identification (RFID) technology introduces the opportunity for increased material and product visibility by facilitating easy tracking and identifying of containers and their contents. Throughout the manufacturing or distribution processes, this technology has been utilized by various organizations. In addition to wide use of disposable RFID tags, reusable RFID tags premises desired economic and efficient supply chain management Considering the reusable RFID tags, the price of the tag,related quality level and logistics policies are crucial. In this study, a conceptual framework for economic analysis of RFID reverse logistics via simulation is presented. Proposed methodology is demonstrated through a hypothetical case study.