W opracowaniu została przeprowadzona dyskusja na temat ekonomicznych efektów zewnętrznych, ze szczególnym naciskiem na efekty technologiczne. Zwrócono także uwagę na problem internalizacji ekonomicznych efektów zewnętrznych wywoływanych przemieszczaniem się (transportem) na obszarach dotkniętych procesem urban sprawl. Badania przeprowadzono dla wszystkich gmin krakowskiego obszaru metropolitalnego (KOM). W ich wyniku przedstawiona została wartość ponoszonych bezpośrednio strat finansowych oraz wartość straconego czasu generowana koniecznością dojazdów i powrotów w przestrzeni KOM-u.
Post-Quantum Cryptography (PQC) attempts to find cryptographic protocols resistant to attacks by means of for instance Shor's polynomial time algorithm for numerical field problems like integer factorization (IFP) or the discrete logarithm (DLP). Other aspects are the backdoors discovered in deterministic random generators or recent advances in solving some instances of DLP. The use of alternative algebraic structures like non-commutative or non-associative partial groupoids, magmas, monoids, semigroups, quasigroups or groups, are valid choices for these new kinds of protocols. In this paper, we focus in an asymmetric cipher based on a generalized ElGamal non-arbitrated protocol using a non-commutative general linear group. The developed protocol forces a hard subgroup membership search problem into a non-commutative structure. The protocol involves at first a generalized Diffie-Hellman key interchange and further on the private and public parameters are recursively updated each time a new cipher session is launched. Security is based on a hard variation of the Generalized Symmetric Decomposition Problem (GSDP). Working with GF(2518) a 64-bits security is achieved, and if GF(25116) is chosen, the security rises to 127-bits. An appealing feature is that there is no need for big number libraries as all arithmetic if performed in Z251 and therefore the new protocol is particularly useful for computational platforms with very limited capabilities like smartphones or smartcards.
Although the explicit commutativitiy conditions for second-order linear time-varying systems have been appeared in some literature, these are all for initially relaxed systems. This paper presents explicit necessary and sufficient commutativity conditions for commutativity of second-order linear time-varying systems with non-zero initial conditions. It has appeared interesting that the second requirement for the commutativity of non-relaxed systems plays an important role on the commutativity conditions when non-zero initial conditions exist. Another highlight is that the commutativity of switched systems is considered and spoiling of commutativity at the switching instants is illustrated for the first time. The simulation results support the theory developed in the paper.