Indian Institute of Management Calcutta

About: Indian Institute of Management Calcutta is a education organization based out in Kolkata, India. It is known for research contribution in the topics: Supply chain & Context (language use). The organization has 415 authors who have published 1354 publications receiving 21725 citations. The organization is also known as: IIMC & IIM Calcutta.

On Detecting Data Flow Errors in Workflows

Abstract: When designing a business workflow, it is customary practice to create the control flow structure first and to ensure its correctness. Information about the flow of data is introduced subsequently into the workflow and its correctness is independently verified. Improper specification of data requirements of tasks and XOR splits can cause problems such as wrong branching at XOR splits and the failure of tasks to execute. Here we present a graph traversal algorithm called GTforDF for detecting data flow errors in both nested and unstructured workflows, and illustrate its operation on realistic examples. Two of these have interconnected loops and are free of control flow errors, and the third one is an unstructured loop-free workflow. Our approach extends and generalizes data flow verification methods that have been recently proposed. It also makes use of the concept of corresponding pairs lately introduced in control flow verification. It thus has the potential for development into a unified algorithmic procedure for the concurrent detection of control flow and data flow errors. The correctness of the algorithm has been proved theoretically. It has also been tested experimentally on many examples.

The mediating effect of logistics integration on supply chain performance : a multi-country study

Abstract: Purpose – The purpose of this paper is to analyze the impact of individual logistics-related factors, namely, supplier involvement (SI), length of supplier relationship (LSR), use of information technology (IT), and logistics integration (LI) on a firm's supply chain performance (SCP) and test for the mediating effect of LI in a multi-country survey conducted in Brazil, Korea and India. The paper also develops a composite variable, supply chain competency (SCC), as an overall measure of the quality of a firm's supply chain and demonstrate its effect on a firm's SCP. Design/methodology/approach – The research methodology was based on designing and administering a survey instrument. Data collected from 187 organizations in Brazil, Korea and India were analyzed using the partial least squares structural equation modeling methodology. Findings – Results show that for the combined data, the direct effects of SI, LSR and IT on SCP are insignificant while LI has a very significant direct effect on SCP. On the ot...

An approach for location area planning in a personal communication services network (PCSN)

Abstract: This paper deals with an approach for planning location areas (LAs) in a personal communication services network (PCSN) to be overlaid on an existing wired network. Given the average speed of mobile terminals, the number of mobile switching centers (MSCs), their locations, call handling capacity of each MSC, handoff cost between adjacent cells and call arrival rate, an important consideration in a PCSN is to identify the cells in every LA to be connected to the corresponding MSC in a cost effective manner. In this work, while planning a location area, we present a two-step approach, namely optimization of total system recurring cost (subproblem I) and optimization of hybrid cost (subproblem II). The planning first determines the optimum number of cells in an LA from subproblem I. Then, it finds out the exact LAs by assigning cells to the switches, while optimizing the hybrid cost which comprises the handoff cost and the cable cost, in subproblem II. This divide-and-conquer strategy provides a practical way for designing LAs. As our approach toward LA planning takes into accounts both cost and network planning factors, this unique combination will be of great interest to PCSN designers. It develops an optimum network planning method for a wide range of call-to-mobility ratios that minimizes the total system recurring cost while still ensuring a good system performance. Our study shows that acceptable results are achievable with a reasonable computational effort, which supports the engineered planning of a PCSN.

Multipath Routing in Ad Hoc Wireless Networks with Omni Directional and Directional Antenna: A Comparative Study

Abstract: Several routing schemes have been proposed in the context of mobile ad hoc network. Some of them use multiple paths simultaneously by splitting the information among multitude of paths, as it may help to reduce end-to-end delay and perform load balancing. Multipath routing also diminishes the effects of unreliable wireless links in the constantly changing topology of ad hoc networks to a large extent. Route coupling, caused by the interference during the simultaneous communication through multiple paths between a pair of source and destination, severely limits the performance gained by multipath routing. Using node disjoint multiple paths to avoid coupling is not at all sufficient to improve the routing performance in this context. Route coupling may be reduced to a great extent if zone disjoint or even partially zone disjoint paths are used for data communication. Two paths are said to be zone disjoint if data communication through one path does not interfere with other paths. Large path length (number of hops) also contributes to the performance degradation resulting in high end to end delay. So zone disjoint shortest multipath is the best choice under high traffic condition. However, it is difficult to get zone disjoint or even partially zone disjoint multiple routes using omni-directional antenna. This difficulty may be overcome if directional antenna is used with each mobile node. In this paper, we have done a comparative study on the performance of multipath routing using omni-directional and directional antenna. The result of the simulation study clearly shows that directional antenna improves the performance of multipath routing significantly as compared to that with omni-directional antenna.