Papers by Keyword: AES

Abstract: AES encryption system is briefly introduced, the function and principle of mask technology has been expressed. Because the vulnerability of the AES encryption system by the energy attacks, the measures need to add to increase the ability of energy analysis of AES. The mask design content is added in the AES encryption system. The mask design of AES encryption was given detailed. Four steps of the mask design process are also given. The conversions and implementation of AES mask design are presented, such as, the transformation of S box and so on. The implementation methods of how to eliminate the mask are given in the final round of AES encryption. It is finally discussed that threaten and influence of energy attack on AES.

Abstract: This paper direct to security and real-time requirements in high-speed network transmission processing, based on SOPC technology, design a High throughput AES encryption/ decryption processing unit with pipelining. The design goal is to optimize the hardware structure and improve the throughput, S-box design and parallel processing structure. Compared with traditional AES crypto-chip has faster rate with encryption and less consumption of resources advantages. This design adopts VHDL hardware description language, use Quartus II 8.0 for the synthesis and routing, and this processing unit is packaged an independent IP core, attached to the Altera provided the Nios II system, finally download and test validation on the DE2 development platform.

Abstract: ZrNi intermetallic compound is used in several application fields due to its very favorable characteristics for the storage of hydrogen. The hydrogen reactions are important, it is vital to examine the evolution of physico-chemical properties at the surface. X-ray photoelectron spectroscopy, is used to follow the evolution of electronic properties of ZrNi versus the ion sputtering in ultra high vacuum in the range 300-600°C. Morever, the evolution of species concentrations at the surface of ZrNi in the range 100-700°C is followed by means of Auger electron spectroscopy. The present results show that temperature and ion sputtering favor significant changes in surface properties of ZrNi. In situ annealing of ZrNi favors the oxygen decontamination associated with segregation of zirconium metal on the surface. The values of binding energies deduced from the reconstruction of XPS spectra, allowed the identification of species present at the surface. The results indicate that nickel is not contaminated and all the obtained sub-oxides are related to bonding states of oxygen with zirconium (Zr₂O, ZrO, ZrO₂ and Zr₂O₃). The ion sputtering of the surface of ZrNi causes preferential sputtering phenomenon. The later results from the removal of surface layers and from the appearance of zirconium oxide layers initially present on the surface. The results obtained by AES show the segregation of impurities (oxygen and carbon) and of zirconium on the surface of ZrNi. AES observations of Zr segregation start to be important above 300°C and this is in agreement with XPS analysis showing a Zr enrichment of the surface of ZrNi.

Abstract: In this paper, an in house production of a 0.5hp induction motor’s rotor is investigated. This investigation considers the induction motor’s efficiency and losses dissipation as an important aspect to determine the rotors efficiency. Through out this project, a new rotor which has 0.35mm steel sheet thickness and 10mm rotor bar slot size is constructed and compared with the existing rotor which has 0.50mm steel sheet thickness and 10mm rotor bar slot size. Once the construction phase of the rotor has been completed an in house motor experiment is done such as the no load, blocked rotor and dc resistance test. Result shows that thinner steel sheet (0.35mm) of the constructed rotor increase the efficiency up to 3.2% and reduces the losses to 17.2 watts compare to the thicker steel sheet rotor (0.5mm). An economical aspect is presented to show the amount of energy and money that can be saved from replacing the existing rotor (0.5mm) with a thinner rotor (0.35mm). As for the annual energy saving (AES) and total cost saving (TCS), the new rotor manage to save 138.7kWh per year and utility billing by RM45.51 per year per motor.

Abstract: Carbon nitride films were synthesized by pulsed laser ablation of graphite target under nitrogen ambience. The third harmonic of a pulsed Nd-YAG laser of 355 nm wavelength and 7 ns pulse duration was focused onto a rotating target at an incidence angle of 45°. The laser fluence at the target surface was set at 30 J/cm2. The carbon nitride films were deposited on (100) silicon substrate kept at room temperature and placed at a distance of 40 mm from the target surface. The CNx films were grown under N2 gas in the pressure range of 5×10-3 to 4×10-1 mbar. The deposited films composition was investigated by different techniques RBS, NRA and AES. We found an N/C ratio equal to 0.4 in the pressure range cited above.

Abstract: Sulfur is the main element which caused Nickel-based alloy embrittlement. In this study, the sulfur in Hastelloy X superalloy was determinated with Auger Electron Spectroscopy (AES) for samples quenched from 1180 °C and aged at 500 °C for different time. Experiments results confirmed the non-equilibrium segregation characteristics of sulfur. The results showed that a segregation peak of sulfur is at about 20 min during ageing. This peak was satisfactorily elucidated by the theory of non-equilibrium grain-boundary segregation. By theoretical calculation, the critical time constant of impurities sulfur atom in the Hastelloy X δs= 357. At the same time, the result provides a theoretical basis for sulfur segregation mechanism.

Abstract: AES is one of the most widely used cryptographic systems. DNA computing has the high efficiency to solve some NP-problems. Therefore many scientists try to combine DNA computing with cryptography. In this paper, an algorithm is designed to simulate a plaintext encrypted by DNA biotechnology and modern cryptography. After mapping the plaintext information as DNA chain and handling the base chain with biological genetic technology, we can get the gene codes form, then using the Rijndael algorithm to deal with the biological chain with cryptography and get the final result. It makes the DNA-based cryptography more effective and more security.

Abstract: Pitting resistance of air cold plasma-oxidation 316L stainless steel was evaluated by exposing the specimens into a ferric chloride solution. The results indicate that the pitting resistance of plasma-oxidized specimens improved obviously. Potentiodynamic polarization curves were measured to study its corrosion behavior. The corrosion mechanism was also interpreted by electrochemical impedance spectroscopy (EIS) and Auger electron spectroscopy (AES).The results reveal that the oxide layer formed by the plasma treatment is much thicker than that without treatment and is double-deck structure, which leads to the change of EIS characteristic of sample surface.

Abstract: We present an experimental study by Auger electron spectroscopy (AES) and low energy electron diffraction (LEED) of the dissolution of about one monolayer of silicon previously deposited at room temperature on Cu (001). The isochronal dissolution has been recorded in the temperature range [50-320°C] (annealing rate 1.5°C/min). The plateau observed in the kinetics dissolution for temperatures between 95°C and 240°C, reveals the formation of an intermetallic two dimensional superficial phase thermally stable in this range of temperature. On the plateau, LEED patterns show the formation of a (5x3) superstructure. Above 255°C, we observe a very fast dissolution of the surface alloy characteristic of a first-order surface transition. Isothermal dissolutions kinetics have been recorded above and under the surface transition temperature (250°C and 270°C). From these measurements, we have evaluated bulk diffusion coefficients of Si in Cu assuming a local equilibrium. The diffusion coefficients measured within this hypothesis at 250°C and 270°C are respectively higher and lower than those extrapolated from high temperature measurements for Ge in Cu.

Abstract: Depending on the thermodynamic, structural and diffusion properties of the system, a thin deposit dissolves into a substrate by different mechanisms. In this communication these different behaviours, investigated by surface analytical techniques (AES, XPS, STM, UPS, etc) [ - ], are reviewed. The experiments were also supported by computer simulations. The obtained results are compared and it is summarized how different parameters influence the dissolution of a thin film in a substrate. Furthermore, it is show that i) the volume dissolution kinetics is different on the atomic-/nano-scale than on the microscopic scale due to the diffusion asymmetry ii) the volume and GB diffusion in one measurement can be separated and iii) pure (C-kinetic) GB diffusivities can be determined from thin film kinetics measurements performed under adequate conditions.