Proposals to improve the reproducibility of biomedical research have emphasized scientific rigor. Although the word "rigor" is widely used, there has been little specific discussion as to what it means and how it can be achieved. We suggest that scientific rigor combines elements of mathematics, logic, philosophy, and ethics. We propose a framework for rigor that includes redundant experimental...

We define NanoJava, a kernel of Java tailored to the investigation of Hoare logics. We then introduce a Hoare logic for this language featuring an elegant approach for expressing auxiliary variables: by universal quantification on the outer logical level. Furthermore, we give simple means of handling side-effecting expressions and dynamic binding within method calls. The logic is proved sound a...

We propose and study coercive subtyping, a formal extension with subtyping of dependent type theories such as Martin-LL of's type theory NPS90] and the type theory UTT Luo94]. In this approach, subtyping with speciied implicit coercions is treated as a feature at the level of the logical framework; in particular, subsumption and coercion are combined in such a way that the meaning of an object ...

The existence of a coalition strategy to achieve a goal does not necessarily mean that the coalition has enough information to know how to follow the strategy. Neither does it mean that the coalition knows that such a strategy exists. The article studies an interplay between the distributed knowledge, coalition strategies, and coalition “know-how” strategies. The main technical result is a soun...

Some potential application domains of hybrid multimodal logic strongly suggest typing of states and imposing type–constraints on modalities. We investigate logical/computational cost of such an extension, and find out that, in the case of a very simple system of types, there is none: the extension essentially preserves both expressivity and complexity of hybrid multimodal logic. Use of types sh...

Several systems that promise a logical view of state in programming have been proposed in the literature. We investigate the syntax and semantics of one of these systems called LLMS, developed by Uday Reddy. We show that the existent categorical deenition of a model of LLMS is too conservative and introduce a neat way of revising the deenition. We give a concrete construction in a Dialectica ca...

Abstract In this paper we treat metasequents—objects which stand to sequents as formulas—as first class logical citizens. To end provide a metasequent calculus, sequent calculus allows us directly manipulate metasequents. We show that the various calculi consider are sound and complete w.r.t. appropriate classes of tetravaluations where validity is understood locally. Finally use our give direc...

Recently two attacks on the Pomaranch stream cipher have been described pointing to two weaknesses in the original design, namely the IV initialization procedure, and the characteristic polynomial used in the jump registers. The latter weakness has already been repaired as described in a previous note by the authors [1]. In this note we provide a simple tweak which effectively counters the atta...

We argue that if the message expansion code of SHA-1 is replaced by a linear code with a better minimum distance, then the resulting hash function is collision resistant. To support this argument, we characterize the disturbance vectors which are used to build local collision attacks as a linear code. This linear code is the xor-sum of two codes, the message expansion code and a linear code rep...