We are all shaped by the tools we use, in particular, the formalisms we use shape our thinking habits, for better or for worse, and that means that we have to be very careful in the choice of what we learn and teach, for unlearning is not really possible.

– E Dijkstra

There seems to be a popular belief that a work only deserves to be qualified as ‘scientific’ if it is supported by ‘empirical evidence’. But computer science is rooted both in speculative sciences such as mathematics and experimental sciences such as physics. Verificationism upholds an optimistic view, that is, it is possible to formulate true general laws on the basis of particular experiences. This optimism provides a generalized attitude among scientists that precisely leads them to seek the confirmation of their theories in experience. Unless we admit a priori that regularities cannot be causal: there must be some kind of rationality in the universe that is within reach of human mind. Falsificationism considers in a rather pessimistic way that induction is not possible. Scientific hypotheses are no more than mere conjectures that are provisionally accepted until a new experience appears to refute them.

Neither verificationism nor falsificationism can give a full account of the reality of scientific activity in all its magnitude. And both, considered as methodological stances, refer to something that is beyond factual experience. Paying attention only to empirical evidence is not acceptable, especially if the consideration of correctness of reasoning is set aside, since, at least, empirical evidence must be adequately interpreted with good reasons. Experimentation without the guide of speculative thinking is worthless. In the end, the conclusion is that experience and speculation must go hand in hand in the way of science.

The first paper of this issue, “Software Design of Water Supply System for Irrigation”, by John Jiya Musa, Alikali Babawuya, Adeoye Peter Aderemi and Micheal Alaba Oluwasegun, proposes an automated irrigation system that ensures efficient use of available water. The software—IrrigateSoft2009—is implemented using Microsoft Visual Basic 6.0. The paper concludes that irrigation activities can be scheduled at any time with minimal human or physical intervention, and this is made possible by the development of this program.

The second paper, “Minimum Spanning Tree-Based Approach for Reliability Estimation of COTS-Based Software Applications”, by Kirti Seth, Arun Sharma and Ashish Seth, focuses on reliability model and reliability analysis techniques for architecture-based reliability evaluation. The paper proposes that the traditional approaches for software reliability analysis treat the software as a whole, use test data during software test phase and model only the interactions with outside world; these are known as black box models. These models ignore the structure of the software made out of components and reliability of individual components, and thus are not appropriate to model Component-Based Software (CBS). The authors have concluded that the proposed approach will further be validated on some real application, and for this data will be collected.

The third paper, “SOA in Business Organization”, by S Nirmala Sugirtha Rajini and T Bhuvaneswari, highlights how the Service-Oriented Architecture (SOA) is important in business organizations based on the proposed architecture diagram. The architecture shows how corporate missions and strategies can be mapped onto business and supporting services. The authors present a case study where the functionality of the proposed SOA is implemented in a business organization. The paper further analyzes the usage of SOA to solve integration complexity problem and facilitates broad-scale interoperability and unlimited collaboration across the organization.

The fourth paper, “Detection of Bridging Fault in Reversible Circuits”, by Hafizur Rahaman, Dipak K Kole, Debesh K Das and Bhargab B Bhattacharya presents the testability issue of reversible circuits under the bridging fault model. The paper proposes a design for testability technique to achieve the universal test set. For further investigation, the authors suggest that new fault models are required for detection of reversible circuits under quantum domain.

The next paper, “A Comparative Study of the Defuzzification Methods in an Application” by Nidhi Kataria explores different defuzzification methods reported in literature, using the base problem of feeding according to the protein and energy level. Ten observations for energy and protein levels are taken and the fuzzy rules are applied on them to find a solution. The results obtained are then defuzzified using five methods. The paper concludes that centroid, bisector and MOM methods are better as compared to the LOM and SOM methods.

The last paper, “Efficient Reactive Routing Protocols in Ad Hoc Networks”, by Rashmi Sharma provides an overview of a wide range of on-demand routing protocols proposed in the literature. It presents a qualitative analysis of on-demand routing protocols and suggests which protocol performs best in large networks. The results show that there is a need for routing protocols specifically tuned to the characteristics of ad hoc networks.

-- C R K Prasad
Consulting Editor