Abstract:

In this research article, the twelve ‘direct methods’ developed by different researchers to solve Transportation Problems (TPs)during the period 2012 – 2021 is considered as one group and twenty one‘challenging TPs (balanced and unbalanced) identified and acknowledged from various published articles and textbooks is considered as another group. We assessand discuss the performance of each ofthe direct methods on the challenging TPs. and brings out the fact and fantasy. Our aim is to encourage and motivate the future author(s) to develop better and best methods to deliver optimal solutions directly to all the TPs.Most of the direct methods introduced are easy to understand, easy to apply, consumes less time, innovative and different from the existing methods. We appreciate the contributions of the authors. However, in reality, testingoutcomes by their methods on the challenging TPs authenticate that no one method has produced optimal solution directly to all the identified TPs. Consequently, no author(s) can claim that their introduced method is direct. Each ‘direct method’ introduced is just a method to generate an initial basic feasible solution (IBFS) only and not a direct method. The added advantage of this article is toassess the performance of any innovative method presented on TP in the future, the acknowledged‘challenging problems’ may be trialed for testing and validating the proposed novel method. Really, the identified ‘challenging problems’ create a challenge to the direct methods.

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