Comments on ‘Evolutionary neural network modelling for software cumulative failure time prediction’ by Liang Tian and Afzel Noore [Reliability Engineering and System Safety 87 (2005) 45–51]

This paper [Tian L, Noore A. Evolutionary neural network modelling for software cumulative failure time prediction. Reliab Eng Syst Saf 2005; 87:45–51] purports to present a useful means of predicting the cumulative failure time function for software reliability growth. In fact, the nature of the ‘prediction’ is too simplistic to be of use. Furthermore, the authors' claims for the accuracy of the predictions appear to be without value.     

Reply to “Comments on ‘Geomechanical and Geochemical Evidence of Piezonuclear Fission Reactions in the Earth's Crust’ by A. Carpinteri and A. Manuello” by U. Bardi and G. Comoretto

In the paper entitled “Comments on ‘Geomechanical and Geochemical Evidence of Piezonuclear Fission Reactions in the Earth's Crust’ by A. Carpinteri and Manuello” by U. Bardi and G. Comoretto, the authors criticise the hypothesis based on piezonuclear reactions for the interpretation of the compositional evolution of the Earth's crust. We report a detailed reply of how the traditional theories, used by the authors of the comments, are obviously inadequate to describe this new kind of nuclear phenomena. Only very recently, independent authors proposed a theoretical model explaining the anomalous energy emissions in the form of neutrons, involved in piezonuclear reactions, during fracture of nonradioactive rocks. It is also known how the evidences that Bardi and Comoretto claim to be non‐existent could be found in many independent works that appeared in most important journals about unexplained questions of the Earth's crust and environment. The data reported in the original work and the details included in this reply show that it is incorrect to consider impossible or simply to ignore the existence of unexplained phenomena only because they cannot be described by traditional models and conventional theories.     

Reply to “Comments on ‘Evaluation of nuclear safety from the outputs of computer codes in the presence of uncertainties’ by W.T. Nutt and G.B. Wallis,” by Y. Orechwa

We respond to comments regarding a previous paper. We conclude that both the coverage and bracketing approaches to statistical sampling are valid and self-consistent. They differ in the underlying probabilistic statement of the criteria.A re-examination of the application of multiple criteria to decision making in nuclear safety leads us to an alternative approach we have called the testing approach. In this approach the physical criteria may be absorbed into a "black box" in which the code makes calculations and the whole process is treated as a test of a single outcome in non-parametric statistics. Using the testing approach one can determine whether or not computer code outputs simultaneously satisfy a set of physical criteria with 95% confidence that the criteria are satisfied with 95% probability, using only 59 runs. This conclusion is independent of the number of criteria and of any inter-dependencies between the outputs from the code.     

Comments on ‘Reliability and performance analysis for fault-tolerant programs consisting of versions with different characteristics’ by Gregory Levitin [Reliability Engineering and System Safety 86 (2004) 75–81]

This paper [Levitin G. Reliability and performance analysis for fault-tolerant programs consisting of versions with different characteristics. Reliab Eng Syst Safety 2004;86:75–81] presents a detailed reliability and performance analysis of fault-tolerant programs. Unfortunately, the treatment is dependent upon a key assumption: ‘Failures of versions for each component are statistically independent…’ (Section 2). Such an assumption is not justified.     

Comments on “Reliability-centered predictive maintenance scheduling for a continuously monitored system subject to degradation” by X. Zhou, L. Xi and J. Lee [Reliab Eng Syst Saf 2007; 92: 530–534]

This short communication conducts a critical review on the subject paper, and lists several errors found in it.