ارزیابی عملکرد سیستم های برنامه ریزی منابع سازمانی (ERP) با ریاضیات فازی

An enterprise resource planning (ERP) system is a complex network composed of various business processes. This paper proposes a method based on stochastic-flow network model to evaluate the performance of an ERP system depending upon the fuzzy linguistic results of the ERP examination of the users involved. The nodes in the network denote the persons responsible for the business tasks during the processes. The arcs between nodes denote the process precedence relationships in the ERP system. When the process starts, the documents are initiated from the source node to its succeeding nodes. Finally, the documents are released in the destination node. Thus, the performance of an ERP system is related to the document flow under the network. The failure of an ERP system is therefore described as in the condition that the flow of the system is under the acceptable level d. By using the fuzzy linguistic results of the ERP examination of the users, we propose a fuzzy linguistic performance index, defuzzified from the probability of maximal flow not less than d, to evaluate the performance of an ERP system. An algorithm is subsequently proposed to generate the performance index, which can be used to assess the system performance either before or after the system going live.

In decades, adopting an enterprise resource planning (ERP) system has been a promised way for corporation to gain competition advantages in the world (Jones and Young, 2006, Sebastianelli and Rishel, 2003 and Tsai et al., 2007). Many researchers have contributed methods to evaluate the performance of ERP systems. These researches can be viewed as two general parts in development. One part is to investigate the financial performance when corporation invested an ERP system. For example, Wu et al. (2007) proposed a method to quantify the tangible and intangible performance of an ERP system. The tangible aspect was analyzed by Hochstrasser model, and the intangible one was quantified by fuzzy evaluation approach which combined nine value drives in corporation value creation processes. Another part, the majority researches, are on the manipulations of critical factors/items that can be obtained from various ways. The first way is by literature review, such as the work of Dowlatshahi (2005) who surveyed current ERP literatures and identified the four ERP strategic factors (cost of ERP implementation, implementation time and return on investment issues, ERP employee training, and effective use of ERP features/applications), and the work of Al-Mashari et al. (2003) who concluded a taxonomy of the critical success key factors (SKF) involving technical and organizational imperatives. The second way is from questionnaire, such as those done by Lin et al. (2004) who used the data envelopment analysis approach to evaluate the relationship between ERP continuous investment and technical efficiency. They also utilized the Tobit regression to investigate the relationship between efficiency scores and the ERP continuous investment based on the concept of total cost ownership. The third way are from heuristics such as the work of Chand et al. (2005) who provided a balanced-scorecard based framework for valuing the strategic performance of an ERP system, the work of Yang et al. (2007) who presented a performance evaluation model of ERP implementation utilizing fuzzy measures, the work of Chang et al. (2007) who constructed a conceptual model to evaluate the performance and competitive advantages associated with ERP from a supply chain management perspective, and the work of Lin et al. (2006) who proposed a statistical method based on Parasuraman and a revised performance evaluation matrix to set up a standard performance upper and lower control limits in terms of Taguchi method and Shewhart control charts.

In practical application, a clearly meaningful performance index is more advantageous than that of the traditional numbers. Especially, when the index is objectively obtained from the analytical model, the conviction for the index is obvious. This paper proposed a fuzzy linguistic performance index based on flow network model to evaluate the performance of an ERP system depending upon the linguistic grades of an ERP examination of the company users involved. At first, the ERP system is proposed to be modeled by a stochastic-flow network model. Then, through the algorithm proposed in this paper, the probability Rd is generated. After defuzzified from Rd, a fuzzy linguistic performance index View the MathML sourceR∼d is obtained. By the illustration of numerical examples, the proposed approach is easily to be fulfilled and can be took place at the ERP pre-implementing stage to help making decision such as the date of system online, or at a regular interval within the system execution to assess the ERP performance under the company’s people floating.