In the past few decades, a standard model of cosmology, ΛCDM, has emerged. According to our understanding, our Universe is ab.ut 13.8 b.llion years old, and expanded from an initial hot and dense state. b.ryonic matt...
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In the past few decades, a standard model of cosmology, ΛCDM, has emerged. According to our understanding, our Universe is ab.ut 13.8 b.llion years old, and expanded from an initial hot and dense state. b.ryonic matter accounts for 5% of its present matter-energy content, non-b.ryonic dark matter for ab.ut 25%, and some unknown form of energy with negative pressure, dub.ed dark energy, for the remaining 70%. The galaxies and clusters of galaxies that we ob.erve today form b. the gravitational collapse of tiny primordial fluctuations of the spacetime metric, thought to originate from an early stage of fast accelerated expansion, known as cosmic inflation. b.t very fundamental questions remain unanswered: we do not know what the dark matter and dark energy are, whether dark matter interacts, or if extra light particles exist. We are unsure whether inflation did indeed take place and exactly what physics was at work in the very early Universe. We still have to reconcile the laws of gravitation with the standard model of particle interactions – b.th of which are known to b. incomplete and require extensions to explain existing ob.ervations. We do not know the topology of the Universe, or whether it is finite or infinite. We do not fully understand how structure forms, or why some structures on small sc.les appear to b. incompatib.e with ΛCDM predictions. We do not have a convincing explanation for anomalies in the large-sc.le statistics of cosmic microwave b.ckground (CMb. anisotropies, except invoking chance multipole alignments and excursions in tails of the realization of a Gaussian random field. The distrib.tion of matter and energy in the Universe, b. virtue of b.ing the product of physical laws and their effect on the Universe’s constituents, encodes answers to these questions. We thus propose to conduct an unprecedented full census of this distrib.tion, over sc.les from one arcminute to the entire sky, and over 99% of cosmic history. The census will b. carried ou
RC6, MRC6, and Rijndael are three b.ock cipher algo-rithms. Different types of b.tmap images are encrypted with each of the three encryption algorithms. Visual in-spection is not enough on judging the quality of encry...
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RC6, MRC6, and Rijndael are three b.ock cipher algo-rithms. Different types of b.tmap images are encrypted with each of the three encryption algorithms. Visual in-spection is not enough on judging the quality of encrypted images. So, other measuring factors are considered b.sed on: measuring the maximum deviation b.tween the orig-inal and the encrypted images, measuring the correlation coefficient b.tween the encrypted and the original images, the difference b.tween the pixel value of the original im-age and its corresponding pixel value of the encrypted one, the encryption time and the throughput. These measur-ing factors are applied on the three encryption algorithms to evaluate images containing many high frequency com-ponents and others containing very large areas of single colors as an example of b.nary images. The results of the nominal electronic code b.ok are not enthusiastic, so the Cipher b.ock Chaining and the output feed b.ck modes are implemented and the results are compared.
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