Probabilistic Models in Cryptography, Coding Theory and Tests for PRNG

2000 Mathematics Subject Classification: 94A29, 94B70This paper is a review of some applications of probabilistic models in cryptography, coding theory and tests for pseudo-random number generators (PRNG). Using quasigroup transformations, we design streams ciphers and error-correcting codes with suitable properties. Some tests for pseudo random number generators are designed, too. They are based on random walk on discrete coordinate plane

Application of Quasigroups in Cryptography and Data Communications

In the past decade, quasigroup theory has proven to be a fruitfull field for production of new cryptographic primitives and error-corecting codes. Examples include several finalists in the flagship competitions for new symmetric ciphers, as well as several assimetric proposals and cryptcodes. Since the importance of cryptography and coding theory for secure and reliable data communication can only grow within our modern society, investigating further the power of quasigroups in these fields is highly promising research direction. Our team of researchers has defined several research objectives, which can be devided into four main groups: 1. Design of new cryptosystems or their building blocks based on quasigroups - we plan to make a classification of small quasigroups based on new criteria, as well as to identify new optimal 8–bit S-boxes produced by small quasigroups. The results will be used to design new stream and block ciphers. 2. Cryptanalysis of some cryptosystems based on quasigroups - we will modify and improve the existing automated tools for differential cryptanalysis, so that they can be used for prove the resistance to differential cryptanalysis of several existing ciphers based on quasigroups. This will increase the confidence in these ciphers. 3. Codes based on quasigroups - we will designs new and improve the existing error correcting codes based on combinatorial structures and quasigroups. 4. Algebraic curves over finite fields with their cryptographic applications - using some known and new tools, we will investigate the rational points on algebraic curves over finite fields, and explore the possibilities of applying the results in cryptography

Analysis of the recommendation algorithm in Cohesy

Pervasive health care takes steps to design, develop, and evaluate computer technologies that help citizens participate more closely in their own healthcare, on one hand, and on the other to provide flexibility in the life of patient who lead an active everyday life with work, family and friends. This paper presents a novel collaborative algorithm that generates recommendations and suggestions for preventive intervention. The main purpose of this algorithm is to find the dependency of the users’ health condition and physical activities he/she performs. The recommendation algorithm, presented in this paper, is part of the Collaborative health care system model called COHESY. COHESY improves quality of care and life to its users, by offering freedom to enjoy life with the confidence that a medical professional is monitoring theirs health condition

Phyllometric study of some wine grapevine cultivar (vitis vinifera l.) from the Balkan subgroup (subconvarietas balcanica negr.)

The aim of investigations was to establish the basic leaf characteristics of grapevine cultivars of balkan subgroup, with the phyllometric researches. Ten cultivars for red wine production (Blatina, Vranec, Kratoshija, Teran, Kadarka, Prokupec, Stanushina, Melnik, Mavrud and Plovdina) and four cultivars for white wine productio (Zilavka, Sipon, Zupljanka and Smederevka) were studied. The established standards has the practical meaning in the description and differeniation of eventual biotypes and clones in the population of this cultivars throught the clonal selection. On the base of obtained results from the cluster analysis of phyllometric parametars the clasification of 14 investigated cultivars was done. According to the values closeness of phyllometric characteristics the cultivars are classified in clusters rom witch can determine the differences or similarities between the ecxaminated cultivars. The cluster analysis are made. For the classification of cultivars in the first cluster analyze we used 19 phyllometric descriptors from the GENRES List of primary descriptors, part II. For the second cluster analyse the parapetars from the "leaf method" are used. According to the phyllometric characteristics in the both cluster analysis very closeness linkage has the cultivars mavrud and plovdina and kratosija and vranec. This means that there lot of common leaf characteristics between these cultivars