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Sign Change Fault Attacks on Elliptic Curve Cryptosystems
This paper presents a new type of fault attacks on elliptic curve scalar multiplications: Sign Change Attacks, which produces points which do not leave the curve and are not easily detected. Expand
A new CRT-RSA algorithm secure against bellcore attacks
This paper describes a new algorithm to prevent fault attacks on RSA signature algorithms using the Chinese Remainder Theorem (CRT-RSA), and proves that the new algorithm is secure against the Bellcore attack. Expand
On Logics with Two Variables
Abstract This paper is a survey and systematic presentation of decidability and complexity issues for modal and non-modal two-variable logics. A classical result due to Mortimer says that theExpand
Back and forth between guarded and modal logics
The characterization theorem provides a semantic characterization of μGF within an appropriate fragment of second-order logic, in terms of invariance under guarded bisimulation, and translations between the guarded and modal domains make the intuitive analogy between guarded andModal logics available as a tool in the further analysis of the model theory of guarded logics. Expand
Two variable first-order logic over ordered domains
  • Martin Otto
  • Computer Science, Mathematics
  • Journal of Symbolic Logic
  • 1 June 2001
Abstract The satisfiability problem for the two-variable fragment of first-order logic is investigated over finite and infinite linearly ordered, respectively wellordered domains, as well as overExpand
Two-variable logic with counting is decidable
We prove that the satisfiability and the finite satisfiability problems for C/sup 2/ are decidable. C/sup 2/ is first-order logic with only two variables in the presence of arbitrary countingExpand
Querying the Guarded Fragment
Finite guarded bisimilar covers of hypergraphs and relational structures are investigated, and Rosati's finite chase is substantially generalised, to prove for guarded theories F and (unions of) conjunctive queries Q that Q istrue in each model of F iff Q is true in each finite model ofF. Expand
Modal characterisation theorems over special classes of frames
It is found that monadic second-order logic is no more expressive than first-order as far as bisimulation invariant properties are concerned — though both are more expressive here than basic modal logic. Expand
Modal characterisation theorems over special classes of frames
  • A. Dawar, Martin Otto
  • Mathematics, Computer Science
  • 20th Annual IEEE Symposium on Logic in Computer…
  • 26 June 2005
The present investigation primarily concerns ramifications for specific classes of structures defined through conditions on the underlying frames, with a focus on frame classes that play a major role in modal correspondence theory and often correspond to typical application domains of modal logics. Expand