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In this report we present a framework for implementing arbitrary $n$-outcome quantum measurement as a sequence of two-outcome measurements requiring only single ancillary qubit. Our procedure is the same as one presented in [Phys. Rev. A 77, 052104 (2008)] but in addition offers particular construction for a two-outcome partial measurements. We exemplify this framework on the unambiguous state discrimination. In the simplest case it gives the same construction as is known, if we opt for performing conclusiveness measurement first. However, it also offers possibility of performing measurement for one of the state outcomes, which shows flexibility of presented framework., Comment: 9 pages, 7 figures

The appealing feature of quantum key distribution (QKD), from a cryptographic viewpoint, is the ability to prove the information-theoretic security (ITS) of the established keys. As a key establishment primitive, QKD however does not provide a standalone security service in its own: the secret keys established by QKD are in general then used by a subsequent cryptographic applications for which the requirements, the context of use and the security properties can vary. It is therefore important, in the perspective of integrating QKD in security infrastructures, to analyze how QKD can be combined with other cryptographic primitives. The purpose of this survey article, which is mostly centered on European research results, is to contribute to such an analysis. We first review and compare the properties of the existing key establishment techniques, QKD being one of them. We then study more specifically two generic scenarios related to the practical use of QKD in cryptographic infrastructures: 1) using QKD as a key renewal technique for a symmetric cipher over a point-to-point link; 2) using QKD in a network containing many users with the objective of offering any-to-any key establishment service. We discuss the constraints as well as the potential interest of using QKD in these contexts. We finally give an overview of challenges relative to the development of QKD technology that also constitute potential avenues for cryptographic research., Revised version of the SECOQC White Paper. Published in the special issue on QKD of TCS, Theoretical Computer Science (2014), pp. 62-81

The aim of this thesis on the topic of the Criminological Aspects of Hate Crime is to offer comprehensive point of view on this issues to the reader. The thesis is divided into five separate chapters. The first chapter is focused on definition of hate crime, specific characteristics of this criminality which distinguish it from other types of crime and also on typology of hate crime. The second chapter is concentrated to the Czech substantive legal regulation of hate crime and its possible regulatory options for the future in a first place. In its other part is focused on legal regulation of hate crime in the United States of America, Great Britain and Germany. In the last part of the chapter, the regulations of all these states are compared in terms of method which they used for anchoring hate crime in the legal system and how large their protection of minority is. The third chapter includes the issue of extremism which is defined at first and than divided into individual forms of extremism, based on their ideological bases and pursued aims, Furthermore, the attention is concentrated on the current state of the extremist scene in the Czech Republic, its activities and subjects. The final part of the chapter is devoted to concepts, closely related to extremism, like racism, anti-Semitism,...