Wyniki wyszukiwania - BazTech

1

Tabu Search Against Permutation Based Stream Ciphers

Polak I., Boryczka M.

International Journal of Electronics and Telecommunications

|

2018

|

Vol. 64, No. 2

137--145

EN

Encryption is one of the most effective methods of securing data confidentiality, whether stored on hard drives or transferred (e.g. by e-mail or phone call). In this paper a new state recovery attack with tabu search is introduced. Based on research and theoretical approximation it is shown that the internal state can be recovered after checking 2⁵² internal states for RC4 and 2¹⁸⁰ for VMPC.

2

Algorytmy inspirowane naturą w kryptoanalizie

Polak I., Boryczka M.

Studia Bezpieczeństwa Narodowego

|

2014

|

R. 4, Nr 6

185--197

PL

W dzisiejszych czasach ochrona informacji jest niezwykle istotna, a jednym z elementów zapewniających ową ochronę jest kryptograﬁa. Tu z kolei ważną rolę odgrywa kryptoanaliza, która pozwala badać bezpieczeństwo używanych szyfrów. Oprócz typowo analitycznego podejścia do łamania szyfrów (jak kryptoanaliza różnicowa, kryptoanaliza liniowa czy analiza statystyczna) od kilkunastu lat do tego celu zaprzęga się różnego rodzaju niedeterministyczne systemy inspirowane naturą. Użycie takich technik nie jest do końca intuicyjne – w kryptoanalizie często ważne jest znalezienie jednego konkretnego klucza (rozwiązania optymalnego), a każde inne rozwiązanie daje kiepskie rezultaty, nawet jeśli jest blisko optimum globalnego.

EN

Nowadays protection of information is very crucial and cryptography is a signiﬁcant part of keeping information secure. Here in turn cryptanalysis plays an important role by examining the safety of ciphers used. Besides the analytical approach to ciphers breaking (eg. diﬀerential cryptanalysis, linear cryptanalysis, statistical analysis) for this purpose there are several kinds of non-deterministic, inspired by nature systems applied. It is not intuitive - as in cryptanalysis often it is important to ﬁnd the exact key used (optimal solution) and every other solution is giving poor results, even if it is near global optimum.

3

Ant colony system in ambulance navigation

Bura W., Boryczka M.

Journal of Medical Informatics & Technologies

|

2010

|

Vol. 15

115--124

EN

This paper describes the ant-based vehicle navigation algorithm (known from literature) and then proposes its modification. Because the performance of these two versions of the algorithm is unsatisfactory, the new, really revised algorithm is introduced. Experiments performed on real-world data show, that this new algorithm is much more efficient and gives better results than its predecessors. The proposed algorithm may be used in the rescue, where ambulances need the useful and efficient method to plan a route to the patient.

4

Eliminating Introns in Ant Colony Programming

Boryczka M.

Fundamenta Informaticae

|

2005

|

Vol. 68, nr 1/2

1--19

EN

Ant Colony Programming is a relatively new paradigm based on Genetic Programming and Ant Colony System. We discuss the problem of eliminating introns in Ant Colony Programming. The approach is tested on several approximation problems. The test results demonstrate that the proposed method simplifies significantly the achieved solutions and shortens their evaluation time.

5

Mit efektu cieplarnianego

Boryczka M.

Przegląd Geofizyczny

|

2004

|

Z. 1-2

43-56

EN

Global warming is mostly believed to be caused by the anthropogenic factor of atmosphere's greenhouse effect - increasing carbon dioxide (CO2) content, resulting from carbon combustion. The 1990 IPCC Report forecasted the rise of temperature on Earth in 2030 by 1.5-4.5°C (after the doubling of pre-industrial atmospheric 280 CO(2) ppm content, in the 2xCO(2) scenarios), and the 1995 IPCC Report estimated a 1-3.5°C rise in 2100 (taking into account the sulphate aerosols). Climate warming, however, is mainly affected by natural causes, i.e. increased Sun activity and lower volcanic activity on Earth. It is still unknown which portion of the advancing warming process is caused by the results from the increasing amount of solar energy reaching Earth, and which depends on the anthropogenic nature of atmosphere's greenhouse effect. The following factors point to the prevalence of natural factors: similar regression lines of standardised Sun activity values (Wolf's numbers) and air temperature in Warsaw between 1779-2000, synchronic variations of mean Northern Hemisphere air temperature between 1856-2002, 11-year running means of Wolf's numbers, synchronic fluctuations of Wolf's numbers and centre of mass position of the four biggest planets, and weak correlation between extreme air temperatures and CO(2) concentration evaluated based on carbon combustion amount. Further evidence of natural causes for climate warmings comes from the synchronicity of changes in carbon dioxide concentration and paleotemperature within the last 160 000 years and 450 000 years, reconstructed basing on Antarctic ice cores. Warmings occur every 100 000 years. They are triggered by solar radiation increase in large latitudes, resulting from changes in Earth's orbit and Earth's axis slant (based on the commonly accepted Milankovic theory). "Parallelism" of changes in CO(2) concentration and paleotemperature indicates that the atmospheric carbon dioxide content is shaped by sine changes of solar radiation reaching Earth - through fluctuations of ocean temperatures. Hence, it is more credible to claim that "atmospheric CO(2) concentration increases along with the amount of solar radiation reaching Earth (i.e. when it gets warmer)"

6

Some aspects of ant systems for the TSP

Boryczka M.

Fundamenta Informaticae

|

1998

|

Vol. 35, nr 1-4

197-209

EN

We describe the ant systems and the application of the generative policies improving the performance of the ant systems in the context of the Travelling salesman Problem. The generative policies are derived from the studies carried out in Germany and USA in the sixties. We study the leader (superman) and elite strategies, which have been chosen because of their analogy to the world of real ants. First, we describe three ant algorithms and we introduce a formal description of the ant system. Then we discuss the reflection of the evolutionary computing in the ant systems.