An Analytic Hierarchy Process Approach For Supplier Evaluation and Selection in a Steel Manufacturing Company

Supplier selection is a complex problem involving qualitative and quantitative multicriteria. A trade-off between these tangible and intangible factors is essential in selecting the best supplier. This problem initiated when there are limitations in the capacity in which the managers are compelled to decide about two issues: which suppliers are the best and how much should be purchased from each selected supplier. Varieties of approaches have been applied, in the form of mixed integers, goal, and multi-objective programming to solve this problem. This approaches, being mathematical that have vital problems in considering qualitative factors. These study apply questionnaires to identifj and adopt the important criteria for supplier selection based on related studies by Dickson (1966), Weber (1991) and Zhang's (2003). In this work both tangible and intangible factors in choosing the best suppliers through analytical hierarchy process (AHP) were incorporated into Saaty's (1 980) proposed method. AHP process makes it possible to place the optimum order quantities among the selected suppliers, so that the total value of purchasing (TVP) becomes maximum. The Saaty's (1980) analytical hierarchy process (AHP) which is used in this case study can be useful in involving several decision makers with different conflicting objectives to arrive at a consensus decision. The main contribution of the study was identification of the important criteria for supplier selection process. The criteria found were Trust between key men, followed by net price and re-win percentage. Second contribution or findings was development of a multi-criteria decision model for evaluation and selection which is used for supplier selection in ABC steel company. Finally, the developed model is tested on four supplier selection problems. The results show the models are able to assist decisionmakers to examine the strengths and weaknesses of supplier selection by comparing them with appropriate criteria, sub-criteria and sub sub-criteria. Further more, the systematic effect of this process, can reduce the time taken to select a supplie

Does a long reference list guarantee more citations? Analysis of Malaysian highly cited and review pPapers

Earlier publications have shown that the number of references as well as the number of received citations are field-dependent. Consequently, a long reference list may lead to more citations. The purpose of this article is to study the concrete relationship between number of references and citation counts. This article tries to find an answer for the concrete case of Malaysian highly cited papers and Malaysian review papers. Malaysian paper is a paper with at least one Malaysian affiliation. A total of 2466 papers consisting of two sets, namely 1966 review papers and 500 highly-cited articles, are studied. The statistical analysis shows that an increase in the number of references leads to a slight increase in the number of citations. Yet, this increase is not statistically significant. Therefore, a researcher should not try to increase the number of received citations by artificially increasing the number of references

AHP approach for supplier evaluation and selection in a steel manufacturing company

Supplier selection is one of the most critical activities of purchasing management in supply chain. Supplier selection is a complex problem involving qualitative and quantitative multi-criteria. A trade-off between these tangible and intangible factors is essential in selecting the best supplier. The work incorporates AHP in choosing the best suppliers. The results suggest that AHP process makes it possible to introduce the optimum order quantities among the selected suppliers so that the Total Value of Purchasing (TVP) becomes maximum. In this work, an AHP-based supplier selection model is formulated and then applied to a real case study for a steel manufacturing company in Malaysia. The use of the proposed model indicates that it can be applied to improve and assist decision making to resolve the supplier selection problem in choosing the optimal supplier combination. The work represents the systematic identification of the important criteria for supplier selection process. In addition, the results exhibit the application of development of a multi-criteria decision model for evaluation and selection of suppliers with proposed AHP model, which by scoring the performance of suppliers is able to reduce the time taken to select a vendorPeer Reviewe

Fuzzy Mixed Assembly Line Sequencing and Scheduling Optimization Model Using Multiobjective Dynamic Fuzzy GA

A new multiobjective dynamic fuzzy genetic algorithm is applied to solve a fuzzy mixed-model assembly line sequencing problem in which the primary goals are to minimize the total make-span and minimize the setup number simultaneously. Trapezoidal fuzzy numbers are implemented for variables such as operation and travelling time in order to generate results with higher accuracy and representative of real-case data. An improved genetic algorithm called fuzzy adaptive genetic algorithm (FAGA) is proposed in order to solve this optimization model. In establishing the FAGA, five dynamic fuzzy parameter controllers are devised in which fuzzy expert experience controller (FEEC) is integrated with automatic learning dynamic fuzzy controller (ALDFC) technique. The enhanced algorithm dynamically adjusts the population size, number of generations, tournament candidate, crossover rate, and mutation rate compared with using fixed control parameters. The main idea is to improve the performance and effectiveness of existing GAs by dynamic adjustment and control of the five parameters. Verification and validation of the dynamic fuzzy GA are carried out by developing test-beds and testing using a multiobjective fuzzy mixed production assembly line sequencing optimization problem. The simulation results highlight that the performance and efficacy of the proposed novel optimization algorithm are more efficient than the performance of the standard genetic algorithm in mixed assembly line sequencing model

Ketidakstabilan Ekspor dan Ekonomi Indonesia

Perekonomian Indonesia adalah perekonomian yang menganut sistem ekonomi terbuka. Di dalam sistem ini lalu lintas ekonomi Internasional mengambil peranan yang penting di dalam perekonomian dan pembangunan suatu negara. Pentingnya lalu lintas ekonomi Internasional bagi Indonesia dapat dilihat dari rasio perdagangan luar negeri terhadap Produk Domestik Bruto (PDB)

A review of supplier selection methods in manufacturing industries

In today’s highly competitive environment, an effective supplier selection process is very important to the success of any manufacturing organization. In this context, supplier selection represents one of the most important functions to be performed by the purchasing department. Supplier selection is a multi-criterion problem which includes both qualitative and quantitative factors (criteria). A trade-off between these tangible and intangible factors is essential in selecting the best supplier. A number of models and techniques have been developed to deal with selecting and evaluating suppliers. In this paper, different selection methods concerning supplier selection are discussed and the advantages and disadvantages of selection methods, especially the Analytic Hierarchy Process (AHP), are illustrated and compared

The Concept of Integrating Virtual Group (VG) and Agile Supplier Selection (ASS)

Agile Manufacturing (AM) is a new concept in manufacturing intended to improve the competitiveness of firms. In 21st century, businesses in order to overcome their competitors, should be able to handle challenges of demanding customers seeking high quality, low cost products and also become more flexible with their specific and rapid changing needs. One of the recent concepts in support of flexibility for factories is Virtual Group (VG). This concept enables the appropriate application of lean and agile concepts to be combined in a cellular manufacturing for different stages of production with in a factory.Flexibility of the supply chain in manufacturing counters the uncertainty in the decision parameters. A supply chain adapts the changes if it is flexible and agile in nature. Integration of appropriate Agile Suppliers Selection (ASS) and Virtual Group (VG) is proposed in this paper. It is argued that the concept of VG by its own is not sufficient for providing flexibility. Therefore, consideration should be taken towards other factors, such as supplier notices, affecting the factory production line in which VG are used. A combination concept comprising VG and supplier is considered in this model. The significance of this subject relies on the producers who confront variable and standard combination factors, as well as manufacture standard and special products. This paper classifies both VG and supplier groups based on the three concepts: Lean, Agile, and Leagile

Job sequencing and layout optimization in virtual production line

Most of the problems involving the design and planning of manufacturing systems are combinatorial and NP-hard. It covers all aspect of creating and operating a manufacturing system before it is implemented. The main activities in creating and operating a manufacturing system are determining the job size, resources needed, equipment layout, routing sequence, and process scheduling. This problem must be solved before it is implemented in real factory. A new trend is using virtual factory approach for testing and validating the proposed design and planning. Designer will have feel at the factory while doing layout planning and design. The contribution of this paper is the integration of two optimization models such as: layout and sequence (job) optimization to those factories who want to produce the various kinds of products with fixed and changeable machine locations as integrated approach for designing a virtual production line. Due to the combinatorial nature of the solution spaces, genetic algorithm is applied for both sequencing and layout. A case study is also reported to demonstrate the feasibility of the proposed approach