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The Value of Inventory Accuracy in Supply Chain Management: Correlation Between Error Sources and Proactive Error Correction
Assaf Avrahami,
Evgeni Korchatov
Issue:
Volume 4, Issue 1, March 2019
Pages:
1-15
Received:
18 December 2018
Accepted:
13 February 2019
Published:
1 March 2019
Abstract: One of the key elements in supplay cahin management is accurate information. Decision makers are aware of inaccuracies in inventory levels and, therefore, routinely conduct inventory reviews to correct the discrepancies between IT records and actual inventory. Several studies have investigated error sources and the cumulative effect of errors on holding costs, shortage costs, order-up-to levels and time between inventory counts. In most works, the errors were independent of the demand, which is neither realistic nor accurate. Here we use familiar inventory errors and information scenarios already proposed in several previous papers. We offer a model that considers the correlation between inventory errors and demand. The effect of the relationship between the random variables is tested in the context of several different scenarios. Each scenario contains a different level of information about the underlying demand and inventory errors. We then analyze the effect of changes of the covariance on the cost and time between inventory counts in each scenario. Using these results we formulate the value of information and its dependence on the covariance. We use analytical methods to draw conclusions regarding single parameter set cases and a numerical full factorial study for average multiparameter cases. In both settings, we show that the value of information decreases as the covariance increases. Moreover, the reduction is more significant when the information scenario makes less assumptions. The same behavior is observed in stock review frequency. As covariance increases, the optimal number of periods between inventory reviews drops sharply. Finally, we propose several simple methods for proactive error correction. We show that without prior knowledge, these methods perform better than the basic information scenario. Using these results we are able to formulate recommendations for businesses with different profiles of correlation between demand, and demand and errors, e.g., automated warehouses with weak correlation compared to grocery stores.
Abstract: One of the key elements in supplay cahin management is accurate information. Decision makers are aware of inaccuracies in inventory levels and, therefore, routinely conduct inventory reviews to correct the discrepancies between IT records and actual inventory. Several studies have investigated error sources and the cumulative effect of errors on ho...
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An Optimal Exiting Time for Old Generation Product in Supply Chain
Issue:
Volume 4, Issue 1, March 2019
Pages:
16-25
Received:
12 February 2019
Accepted:
25 March 2019
Published:
18 April 2019
Abstract: (I) Brief problem description: With technology developing, many series products which have several generations appear in one market. The sales of new and old generations of a product in one market influences each other. (II) The study aim: In order to help the supply chain to obtain more benefits, this paper makes a study on the exiting of old generation products. (III) Method: Based on Fisher model and multi-generation product diffusion model, this paper establishes an optimal decision-making model for the exiting time of old generation product, and analyzes the relationship between the optimal exiting time of the old generation product and the technical level of the new generation product. (IV) Result and conclusion: Observations from this study include (1) when the profit of the new generation product sold only and that of the two generations sold simultaneously are the same, it is the optimal time for old generation product to exit market, and (2) the higher the technical level of new generation product is, the earlier old generation product will exit from market, and the more profit supply chain will get. (V) Significance: The research result will help some company make optimal decision-making for the exiting time of old generation product, and get more profit.
Abstract: (I) Brief problem description: With technology developing, many series products which have several generations appear in one market. The sales of new and old generations of a product in one market influences each other. (II) The study aim: In order to help the supply chain to obtain more benefits, this paper makes a study on the exiting of old gene...
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Coordinated Replenishment Policy in an Assembly System Based on Supply-Hub
Jianhong Yu,
Jennifer Shang,
Wenchyuan Chiang
Issue:
Volume 4, Issue 1, March 2019
Pages:
26-38
Received:
4 December 2018
Accepted:
11 January 2019
Published:
26 April 2019
Abstract: The synchronization and coordination of material flows is a key element in the supply chain management. To analyze the effects of coordinated replenishment for components, we consider an assembly system with two component-suppliers, one supply-hub and one manufacturer, under stochastic final product demand. We propose three different strategies: (i) the decentralized replenishment, (ii) the coordinated replenishment without coordinated quantity, and (iii) the coordinated replenishment policy with coordinated quantity for infinite planning horizon. We propose optimal decisions for all strategies. Results show that policy (ii) is always better than policy (i). We further identify the conditions under which the third strategy outperforms the other two. Policy (iii) is better on cost saving and service level, only when it satisfies certain conditions. Numerical studies are conducted to validate the model and to derive managerial implications.
Abstract: The synchronization and coordination of material flows is a key element in the supply chain management. To analyze the effects of coordinated replenishment for components, we consider an assembly system with two component-suppliers, one supply-hub and one manufacturer, under stochastic final product demand. We propose three different strategies: (i...
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The Impact of e-Learning on the Management of Knowledge Among Faculty Members in Private Jordanian Universities
Issue:
Volume 4, Issue 1, March 2019
Pages:
39-47
Received:
25 January 2019
Accepted:
16 April 2019
Published:
29 May 2019
Abstract: This study aimed to identify the reality of e-learning in the three private Jordanian universities (Jerash, Ajloun and Philadelphia) and its impact on the performance of faculty members in these universities. The study society is composed of (620) faculty members in the above mentioned universities. The sample was randomly selected by 35% sample size was (220), the study used the descriptive method and the data were collected by a questionnaire designed for this purpose. The items were composed of 40 items where the researcher created them and analyzed them. Results showed that the availability of e-learning environment was ranked first, Where the mean of the total score was (2.81) and the standard deviation (.80) and in the second place came knowledge of the concept of e-learning with an average (2.71) and a standard deviation (.77), and in the field of education outputs was in the third place with an average of (2.57) and a standard deviation (.66) and the study showed that there are no differences of statistical significance at the level (9≤0.05) variable, years of experience, university level and scientific qualification, except for the existence of differences of statistical significance for the variable of scientific qualification for the University of Ajloun, where the differences were significant and in favor of the scientific degree PhD on the Masters. Based on the previous results, the study has recommended a set of guidance, the most important of which: Review the policies of applying e-learning mechanisms in the light of knowledge management among faculty members.
Abstract: This study aimed to identify the reality of e-learning in the three private Jordanian universities (Jerash, Ajloun and Philadelphia) and its impact on the performance of faculty members in these universities. The study society is composed of (620) faculty members in the above mentioned universities. The sample was randomly selected by 35% sample si...
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