Partially consonant belief functions (pcb), studied by Walley, are the only class of Dempster-Shafer belief functions that are consistent with the likelihood principle of statistics. Structurally, the set of foci of a pcb is partitioned into non-overlapping groups and within each group, foci are nested. The pcb class includes both probability function and Zadeh’s possibility function as special cases. This paper studies decision making under uncertainty described by pcb. We prove a representation theorem for preference relation over pcb lotteries to satisfy an axiomatic system that is similar in spirit to von Neumann and Morgenstern’s axioms of the linear utility theory. The closed-form expression of utility of a pcb lottery is a combination of linear utility for probabilistic lottery and two-component (binary) utility for possibilistic lottery. In our model, the uncertainty information, risk attitude and ambiguity attitude are separately represented. A tractable technique to extract ambiguity attitude from a decision maker behavior is also discussed. 相似文献
The theory of designing block ciphers is mature, having seen significant progress since the early 1990s for over two decades,
especially during the AES development effort. Nevertheless, interesting directions exist, in particular in the study of the
provable security of block ciphers along similar veins as public-key primitives, i.e. the notion of pseudorandomness (PRP)
and indistinguishability (IND). Furthermore, recent cryptanalytic progress has shown that block ciphers well designed against
known cryptanalysis techniques including related-key attacks (RKA) may turn out to be less secure against RKA than expected.
The notion of provable security of block ciphers against RKA was initiated by Bellare and Kohno, and subsequently treated
by Lucks. Concrete block cipher constructions were proposed therein with provable security guarantees. In this paper, we are
interested in the security notions for RKA-secure block ciphers. In the first part of the paper, we show that secure tweakable
permutation families in the sense of strong pseudorandom permutation (SPRP) can be transformed into secure permutation families
in the sense of SPRP against some classes of RKA (SPRP–RKA). This fact allows us to construct a secure SPRP–RKA cipher which
is faster than the Bellare–Kohno PRP–RKA cipher. We also show that function families of a certain form secure in the sense
of a pseudorandom function (PRF) can be transformed into secure permutation families in the sense of PRP against some classes
of RKA (PRP–RKA). We can exploit it to get various constructions secure against some classes of RKA from known MAC algorithms.
Furthermore, we discuss how the key recovery (KR) security of the Bellare–Kohno PRP–RKA, the Lucks PRP–RKA and our SPRP–RKA
ciphers relates to existing types of attacks on block ciphers like meet-in-the-middle and slide attacks. In the second part
of the paper, we define other security notions for RKA-secure block ciphers, namely in the sense of indistinguishability (IND) and non-malleability, and show the relations between these security notions. In particular, we show that secure tweakable permutation families
in the sense of IND (resp. non-malleability) can be transformed into RKA-secure permutation families in the sense of IND (resp.
non-malleability). 相似文献
We show that the center of a flat graded deformation of a standard Koszul algebra A behaves in many ways like the torus-equivariant cohomology ring of an algebraic variety with finite fixed point set. In particular,
the center of A acts by characters on the deformed standard modules, providing a “localization map”. We construct a universal graded deformation
of A and show that the spectrum of its center is supported on a certain arrangement of hyperplanes which is orthogonal to the
arrangement coming from the algebra Koszul dual to A. This is an algebraic version of a duality discovered by Goresky and MacPherson between the equivariant cohomology rings
of partial flag varieties and Springer fibers; we recover and generalize their result by showing that the center of the universal
deformation for the ring governing a block of parabolic category O{\mathcal{O}} for
\mathfrakgln{\mathfrak{gl}_n} is isomorphic to the equivariant cohomology of a Spaltenstein variety. We also identify the center of the deformed version
of the “category O{\mathcal{O}}” of a hyperplane arrangement (defined by the authors in a previous paper) with the equivariant cohomology of a hypertoric
variety. 相似文献
In this paper, we introduce new approximate projection and proximal algorithms for solving multivalued variational inequalities involving pseudomonotone and Lipschitz continuous multivalued cost mappings in a real Hilbert space. The first proposed algorithm combines the approximate projection method with the Halpern iteration technique. The second one is an extension of the Halpern projection method to variational inequalities by using proximal operators. The strongly convergent theorems are established under standard assumptions imposed on cost mappings. Finally we introduce a new and interesting example to the multivalued cost mapping, and show its pseudomontone and Lipschitz continuous properties. We also present some numerical experiments to illustrate the behavior of the proposed algorithms.
We propose the use of a La2O3 (LO) film as the capping layer for improvement of a semiconductor/insulator interface in a solution-processed indium–tin–oxide (ITO) ferroelectric-gate thin-film transistor (FGT) device. It is demonstrated that the LO layer acts as a good barrier film not only for preventing the interdiffusion between the ITO semiconductor and lead–zirconium-titanate (PZT) insulator layers, but also for stabilizing the PZT surface structure. The fabricated FGT device exhibited high Ion/Ioff, large Mw, high μFE and improved retention time of about 109, 3.5 V, 7.94 cm2?V?1?s?1 and 1 day, respectively, which are comparable to or better than those obtained with FGTs fabricated by means of conventional vacuum processes. We also point out that the key origin of the interface improvement is likely due to the incorporation of La into the PZT system, forming a La surface-modified PZT system which is more stable than the pure PZT in terms of Pb volatility and formation of oxygen vacancies. 相似文献
The aim of this paper is to present a nonconvex duality with a zero gap and its connection with convex duality. Since a convex program can be regarded as a particular case of convex maximization over a convex set, a nonconvex duality can be regarded as a generalization of convex duality. The generalized duality can be obtained on the basis of convex duality and minimax theorems. The duality with a zero gap can be extended to a more general nonconvex problems such as a quasiconvex maximization over a general nonconvex set or a general minimization over the complement of a convex set. Several applications are given.On leave from the Institute of Mathematics, Hanoi, Vietnam. 相似文献
The irradiation of nonconjugated bichromophoric systems, diaryl ketones, with ultraviolet light in the presence of hydrogen donors, such as isopropanol or bisbenzhydrol, yields high polymers. Two series of arylketones were investigated, namely bisbenzophenones and bisketotriazoles. The cage reaction, which arises from the cross combination between the acetone ketyl and bisbenzophenone ketyl radicals, was estimated to be very small but may constitute a chain termination reaction in the photopolymerization in isopropanol. The photopolymerization of bisdiketone–dihydrol systems was found to yield polymers with much higher molecular weights than those obtained from the photopolymerization of bisdiketone–isopropanol systems. The photolysis of some binary mixtures of aromatic diketones in the presence of isopropanol yielded statistical copolypinacols. In some favorable cases, the NMR spectrum of the copolymer obtained showed three distinct linkages and from the infrared spectrum intensities the copolymers composition and the number average length of the sequences may be determined. 相似文献
A series of chiral (iminophosphoranyl)ferrocenes (1-3) are highly efficient ligands for Rh- and Ir-catalyzed hydrogenation of a number of unfunctionalized olefins; almost perfect enantiomeric excesses (up to 99% ee) have been achieved under mild reaction conditions. 相似文献