about electronic signatures there are more or less some writings concerning their legal aspect. but in those writings there has been a little attention to credibility and evidential value of the electronic signatures. some questions and ambiguities despite being set before has not been answered at all or answered unsatisfactorily. meanwhile, some authors have made mistakes and some have set tri...

electronic government is a new concept that governments according to level of development implement in different ways. utilizing informational systems in business sections has created potential context for developing electronic government. customer relationship ‎management (crm) is an important system in management that helps to develop electronic government and promote citizenship-based in org...

Finding the exact, quantum corrected metric on the hypermultiplet moduli space in Type II string compactifications on Calabi-Yau threefolds is an outstanding open problem. We address this issue by relating the quaternionic-Kähler metric on the hypermultiplet moduli space to the complex contact geometry on its twistor space. In this framework, Euclidean D-brane instantons are captured by contact...

W e quantify the observation by Kender and Freudenstein [6] that degenerate views occupy a significant fraction of the viewing sphere surrounding an object. This demonstrates that systems for recognition must explicitly account f o r the possibility of view degeneracy. W e show that view degeneracy cannot be detected f rom a single camera viewpoint. As a result, systems designed to recognize ob...

Over the past few years the understanding of the microscopic theory of black hole entropy has made important conceptual progress by recognizing that the degeneracies are encoded in partition functions which are determined by higher rank automorphic representations, in particular in the context of Siegel modular forms of genus two. In this brief review some of the elements of this framework are ...

As generalizations of the seniority model, four Hamiltonians are considered to investigate some of the physics associated with the pairing of parafermions of order p = 2. 2-particle and 4-particle states are explicitly constructed for HA ≡ −G A†A with A† ≡ 1 2 ∑ m>0 c † mc † −m and the distinct HC ≡ −G C†C with C† ≡ 1 2 ∑ m>0 c † −mc † m, and for the time-reversal invariant H(−) ≡ −G (A† − C†)(...

Precise definitions for different degrees of controllability for quantum systems are given, and necessary and sufficient conditions for each type of controllability are discussed. The results are applied to determine the degree of controllability for various atomic systems with degenerate energy levels and transition frequencies. Degrees of controllability for quantum systems and application to...