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Data security is very important in the field of Computer Science. In this paper the encryption algorithm called RC6 will be analyzed and its standard and parallel implementation will be done. First the field of Cryptology is discussed in general terms, then the classification of encryption algorithms according to operation and techniques is explained. RC6 is a symmetric block algorithm derived from the RC5 algorithm. RC6 operates on 128-bit blocks and accepts 128, 192, 256-bit keys until 2040 bytes. In the Advanced Encryption Standard (AES) competition, RC6 managed to rank among the five finalists. The structure of the RC6 algorithm will be analyzed also the encryption and decryption methods. The comparison between standard and parallel implementation will be made.

In the digital world, the demand for data security during communication has increased. Hash functions are one of the cryptographic algorithms that provide data security in terms of data authenticity and integrity. Nowadays, most online applications require user authentication. These authentications are done on the server-side, which he must manage. As the number of applications increases, building a one-way function will be faster for calculating a hash value for small data such as passwords. In this paper, we will present a sequential cryptographic algorithm and its parallel implementation. We performed security analyses, executed comparisons for different amounts of data, and provided steps for further developing this algorithm. With the construction of this one-way function, we have provided the calculation of hash value in a shorter time for data in small quantities, which speeds up the authentication process on the server and thus speeds up the online services provided by the respective applications. A comparison was made between sequential implementation, parallel implementation on the CPU, and parallel implementation on the GPU using CUDA (Computer Unified Device Architecture) platform.

Significance Chandelier cells (ChCs) are a unique type of GABAergic interneuron that form axo-axonic synapses exclusively on the axon initial segment (AIS) of neocortical pyramidal neurons (PyNs), allowing them to exert powerful yet precise control over PyN firing and population output. The importance of proper ChC function is further underscored by the association of ChC connectivity defects with various neurological conditions. Despite this, the cellular mechanisms governing ChC axo-axonic synapse formation remain poorly understood. Here, we identify microglia as key regulators of ChC axonal morphogenesis and AIS synaptogenesis, and show that disease-induced aberrant microglial activation perturbs proper ChC synaptic development/connectivity in the neocortex. In doing so, such findings highlight the therapeutic potential of manipulating microglia to ensure proper brain wiring.

Flexible Job Scheduling Problem presents a relaxation of the Job Scheduling Problem. It falls into the category of NP-hard problems. Our approach is to tackle the problem through usage of a coarse-grained genetic algorithm. Coarse-grained extends the genetic algorithm and thus increasing chances of more fitness landscape to be examined. Solutions are benchmarked with other approaches, through two of the most used datasets. Even though the results are less favourable than other approaches, in few cases our approach reaches the upper bound of the benchmarked solutions, thus impelling us to further investigate on the problem solution.

University scheduling timetabling problem, falls into NP hard problems. Re-searchers have tried with many techniques to find the most suitable and fastest way for solving the problem. With the emergence of multi-core systems, the parallel implementation was considered for finding the solution. Our approaches attempt to combine several techniques in two algorithms: coarse grained algorithm and multi thread tournament algorithm. The results obtained from two algorithms are compared, using an algorithm evaluation function. Considering execution time, the coarse grained algorithm performed twice better than the multi thread algorithm.

In this paper, we describe non invertible matrix in GF(2)which can be used as multiplication matrix in Hill Cipher technique for one way hash algorithm. The matrices proposed are permutation matrices with exactly one entry 1 in each row and each column and 0 elsewhere. Such matrices represent a permutation of m elements. Since the invention, Hill cipher algorithm was used for symmetric encryption, where the multiplication matrix is the key. The Hill cipher requires the inverse of the matrix to recover the plaintext from cipher text. We propose a class of matrices in GF(2) which are non invertible and easy to generate., Comment: 6 pages, 5 figures, "Published with International Journal of Computer Applications (IJCA)"