The main objective of this study is to get a secure broadcasting in real time applications for audio files (precisely the Wave type) and to increase the degree of complexity of the encrypt/decrypt arithmetic operations in the finite . field GF(28) on these files. This objective can be achieved by implementing different proposed architectures, methods and algorithms both in block and stream cipher structure to increase the degree of complexity. For high utilization of resources and fast execution time of operations in cryptographic processes in the proposed cryptographic algorithms, the parallel computing was implemented by using OpenMP directives. The AES Rijndael algorithm has been considered as a base for the developed algorithms in the block cipher systems. To increase the complexity degree of the encryption/decryption operations, the transformation functions, in AES Rijndael (SubByte, MixColumn and ShiftRows) are modified to the new functions (DK- SBOX-AES, 4K-MIX-AES and 5K-SHIFT-AES) respectively. The aforementioned proposed modified functions in addition to AddRoundKey formed the proposed improved AES algorithm. The high degree of complexity for the improved AES (256! * (2-16)! * 4! * 5!) compared to AES Rijndael (256!) has been obtained with little increase in the execution time. In this work, it is found that the OpenMP has the capability to reduce the costs of design / development and time to implement these systems, and to increase the programmer productivity. The execution of parallel programming leads, reducing the operating time to one half or less depends on the number of processors used, for both encryption/decryption processes for the proposed algorithms.
In this article four samples of HgBa2Ca2Cu2.4Ag0.6O8+δ were prepared and irradiated with different doses of gamma radiation 6, 8 and 10 Mrad. The effects of gamma irradiation on structure of HgBa2Ca2Cu2.4Ag0.6O8+δ samples were characterized using X-ray diffraction. It was concluded that there effect on structure by gamma irradiation. Scherrer, crystallization, and Williamson equations were applied based on the X-ray diffraction diagram and for all gamma doses, to calculate crystal size, strain, and degree of crystallinity. I
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