Toward Security Verification against Inference Attacks on Data Trees

This paper describes our ongoing work on security verification against inference attacks on data trees. We focus on infinite secrecy against inference attacks, which means that attackers cannot narrow down the candidates for the value of the sensitive information to finite by available information to the attackers. Our purpose is to propose a model under which infinite secrecy is decidable. To be specific, we first propose tree transducers which are expressive enough to represent practical queries. Then, in order to represent attackers' knowledge, we propose data tree types such that type inference and inverse type inference on those tree transducers are possible with respect to data tree types, and infiniteness of data tree types is decidable.Comment: In Proceedings TTATT 2013, arXiv:1311.505

Construction of Knut Vik Designs and Orthogonal Knut Vik Designs

Following Eluer's method，A. Hedayat constructs some Knut Vik designs. We call them Knut Vik designs of Hedayat in this note. We give Knut Vik designs of Hedayat explicitly and decide when Knut Vik designs of Hedayat are mutually orthogonal

Decompositions of Boolean functions and hypergraphs

Boolean functions are closely reltated to hypergraphs. In fact, Ibaraki and Kameta (1993) sutudied relations between coteries (intersecting simple hypergraphs) and positive Boolean functions. In this paper, we shall show that the set of all simple hypergraphs is lattice-isomorphic to the set of all positive Boolean functions. A decompositions of a given function into a conjunction of self-dual functions were studied by Ibaraki, Kameta (1993) and Bioch, Ibaraki (1995). For a given dual-minor function, using a certain corresponding hypergraph, we shall give the general condition for the decomposition

Pandiagonal Constant Sum Matrices

In the present paper，we study square matrices in which the sum of elements in any row，in any column ，in any extended diagonal add up to a constant. We call such a matrix a pandiagonal constant sum matrix. We will show that the number of independents elements in a pandiagonal constant Sum matrix of order n is n2 - 4n + 3 if n is odd or n2 - 4n + 4 if n is even

Nonexistence of a Protective Plane Minimally Immersed with Some Embeddedness

Assume that M is diffeomorphic to a projective plane minus k points (k≧1), In this paper, we prove that there is no complete minimal embedding of M into R^3. It is also shown that if 1⪯k⪯3, it does not exists a complete minimal immersion of M into R^3 with paralled embedded ends

Harmonic Sections of Tangent Bundles

Let M be an m dimensional smooth Riemannian manifold with metric g. The tangent bundle T(M) over M is endowed with the Riemannian metric g^D, the diagonal lift of g [3], [5]. Let X be a vector field on M. Then it is regarded as a mapping φx of M to T(M). The purpose of this paper is to study under what conditions the mapping φx of Riemannian manifolds is harmonic. § 1 is devoted to describe some basic facts on geometry of tangent bundles. We will see in §2 that the natural projection, π: T(M)→M is a totally geodesic submersion. In the last section, it is proved that when M is compact and orientable, φx: M→T(M) is harmonic iff the first covariant derivative of X vanishes

Nimstring Values for 2 × n Rectangular Arrays II

In the present paper, succeeding the previous paper [4], we continue to study Nimstring values of 2 x n rectangular arrays