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In this paper, low-cost and two-cycle hardware structures of the PRINCE lightweight block cipher are presented. In the first structure, we proposed an area-constrained structure, and in the second structure, a high-speed implementation of the PRINCE cipher is presented. The substitution box (S-box) and the inverse of S-box (S-box−1) blocks are the most complex blocks in the PRINCE cipher. These blocks are designed by an efficient structure with low critical path delay. In the low-cost structure, the S-boxes and S-boxes−1 are shared between the round computations and the intermediate step of PRINCE cipher. Therefore, the proposed architecture is implemented based on the lowest number of computation resources. The two-cycle implementation of PRINCE cipher is designed by a processing element (PE), which is a general and reconfigurable element. This structure has a regular form with the minimum number of the control signal. Implementation results of the proposed structures in 180-nm CMOS technology and Virtex-4 and Virtex-6 FPGA families are achieved. The proposed structures, based on the results, have better critical path delay and throughput compared with other's related works.  相似文献   
3.
Highly active ReS2 nanocatalysts were prepared by CVD method and characterized by XRD, BET -BJH, Raman spectroscopy, XPS, TPR, NH3-TPD, SEM, and HRTEM techniques. Catalytic activities were used in upgrading heavy crude oil using methane as hydrogen source. The results showed a significant increase in API and decrease in sulfur and nitrogen content of crude oil. RSM technique was used to investigate the interactive effects of temperature (200–400 °C), pressure (20–40 bar) and dosage of nanocatalyst (0.5–2 wt. %) on the performance of HDS reaction. The results represent that the maximum predicted HDS activity (74.375%) was estimated under the optimal conditions (400 °C, 20 bars, and 2 wt % of nanocatalyst). Also, the effect of reaction temperature, pressure and dosage of ReS2 nanorods catalyst on HDN of heavy crude oil was investigated and highest efficiency in the HDN process (93%) occurred at 400 °C and 40 bar using 2 wt % ReS2.  相似文献   
4.
Microsystem Technologies - A force sensor utilizing a transformer concept with a ferrofluid core was developed. A ferrofluid reservoir was machined out of Teflon and the open top of the reservoir...  相似文献   
5.

Mapping vulnerability to Saltwater Intrusion (SWI) in coastal aquifers is studied in this paper using the GALDIT framework but with a novelty of transforming the concept of vulnerability indexing to risk indexing. GALDIT is the acronym of 6 data layers, which are put consensually together to invoke a sense of vulnerability to the intrusion of saltwater against aquifers with freshwater. It is a scoring system of prescribed rates to account for local variations; and prescribed weights to account for relative importance of each data layer but these suffer from subjectivity. Another novelty of the paper is to use fuzzy logic to learn rate values and catastrophe theory to learn weight values and these together are implemented as a scheme and hence Fuzzy-Catastrophe Scheme (FCS). The GALDIT data layers are divided into two groups of Passive Vulnerability Indices (PVI) and Active Vulnerability Indices (AVI), where their sum is Total Vulnerability Index (TVI) and equivalent to GALDIT. Two additional data layers (Pumping and Water table decline) are also introduced to serve as Risk Actuation Index (RAI). The product of TVI and RAI yields Risk Indices. The paper applies these new concepts to a study area, subject to groundwater decline and a possible saltwater intrusion problem. The results provide a proof-of-concept for PVI, AVI, RAI and RI by studying their correlation with groundwater quality samples using the fraction of saltwater (fsea), Groundwater Quality Indices (GQI) and Piper diagram. Significant correlations between the appropriate values are found and these provide a new insight for the study area.

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In a galvanizing process a continuous sheet of steel is passed through a bath of molten zinc around a series of rotating rollers. One or more of these rollers are submerged in the bath of molten zinc and are supported by journal bearings that are lubricated with molten zinc. Dynamic characteristics of these bearings influence the quality of the finished galvanized sheet and also determine the production speed. This work presents a theoretical study of these bearings in terms of the damping, stiffness, and inertia coefficients of the film of molten zinc separating the journal from the bearings. This work also addresses the influence of turbulence on the bearing dynamics. The damping, stiffness, and inertia coefficients of journal bearings lubricated with molten zinc are determined for different zinc alloys at 450,650, and 850 °F.  相似文献   
7.
The Journal of Supercomputing - On the battlefield, early detection of armored vehicles can have a positive effect. Because according to this issue, timely and appropriate reactions can be done....  相似文献   
8.
对聚对苯二甲酸乙二醇酯(PET)织物进行碱性水解预处理.通过浸渍法以十二烷基硫酸钠作为分散剂在原始的和经预处理的PET中加入纳米炭黑(CB1515和CB156),纳米二氧化钛(NTO)-NCBs(CB1515或CB156)混合物.以柠檬酸(CA)和次磷酸钠(SHP)分别为交联剂和催化剂,分别在预处理前后的PETs中加入NTO+CB1515和NTO+CB156作对比研究.结果表明,CB156比CB1515更能有效地降低样品的电阻率.加入NTO后,由原始PET所制样品比预处理PET所制样品具有更低的电阻率.然而,这与不加NTO所制样品结果相反.通过增加添加量和改善NCBs和NTO在织物中的分散均匀性,采用CA和SHP可明显降低样品的电阻率.发现NCBs与NTO的协同效应可提高预处理织物的紫外吸收.由原始PET中加入NCB和NTO所制样品比预处理的PET对亚甲基蓝降解具有更高活性.通过添加NTO或CA-SHP可提高活性,前者比后者更有效.  相似文献   
9.
In this paper, the first and second-law analysis for the thermodynamic air-standard Atkinson cycle with an account for heat transfer is performed using finite-time thermodynamics. In order to have more accurate evaluations, the effects of thermodynamic and design key parameters on the performance characteristics of Atkinson cycle are shown. Further, artificial neural network and imperialist competition algorithm are employed to predict and optimize the net work output value versus the minimum cycle temperature and also the compression ratio. The results obtained show that the heat loss is an effective factor of the performance of the cycle and it should be considered in the analysis and comparison of practical internal combustion engines.  相似文献   
10.
This research has investigated the effect of certain geometric parameters on cooling performance of three vortex tubes. The influencing parameters include three length/diameter ratios L/D?=?10, 25, 40, three nozzle cases and each case with number n?=?2, 4, 6 nozzles, three cold orifice/diameter ratios β?=?0.389, 0.5, 0.611 and three inlet pressures Pi?=?2, 2.5 and 3?bar. The experiments are conducted based on three factors, two-level and central composite face-centred design with full factorial. The results are analysed according to the principle of response surface methodology. The goodness of fit of the regression model is inspected using the analysis of variance and F-ratio test. The values of R2 and R2-adjusted are close to 100% which show a very good correlation between the observed and predicted values. The results show that the effect of number of nozzles on the energy separation depends on the L/D values.  相似文献   
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