................................................................................................................................... 6 Introduction............................................................................................................................ 7 Materials and Methods......................................................................................

We consider the security of message authentication code (MAC) algorithms, and the construction of MACs from fast hash functions. A new forgery attack applicable to all iterated MAC algorithms is described, the first known such attack requiring fewer operations than exhaustive key search. Existing methods for constructing MACs from hash functions, including the secret prefix, secret suffix, and ...

In this paper, we consider multiuser space-time block codes (STBCs) for 2 × 2 multiple–input multiple–output (MIMO) uplink transmissions. Using a truncated union–bound (UB) approximation, we propose design criteria of multiuser STBCs for quasi-static fading MIMO multiple access channels (MACs). Next, we demonstrate how, by combining the structure of algebraic perfect STBCs in [10], a family of ...

Management accounting and control systems (MACS) may be defined as part of the global information system, through which it is collected, processed, analyzed and communicated information (financial and nonfinancial, internal and external) used for planning, monitoring and control of different organizational activities, to optimize the use of resources, to support the process of decision making a...

Myeloid angiogenic cells (MACs) play a key role in endothelial repairing processes and functionality but their activity may be impaired by the lipotoxic effects of some molecules like stearic acid (SA). Among the dietary components potentially able to modulate endothelial function in vivo, (poly)phenolic compounds represent serious candidates. Here, we apply a comprehensive multidisciplinary ap...

Context. Hierarchical models of structure formation predict that galaxy clusters grow via mergers of smaller clusters and galaxy groups, as well as through continuous accretion of gas. MACS J0717.5+3745 is an X-ray luminous and complex merging cluster, located at a redshift of 0.5548. The cluster is suspected to host a bright radio relic, but up until now no detailed radio observations have bee...

This paper proposes a variation of the Multiple Ant Colony System for Vehicle Routing Problem with Time Windows (MACS-VRPTW) algorithm, which is based on an Ant Colony System approach, using two ant colonies to minimize first the number of vehicles and then the total traveled distance. As an improvement, the present work proposes to use a modified version specialized for a multiobjective contex...