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101.
Ronak Zarhoun Mohammad Hossein Moaiyeri Samira Shirinabadi Farahani Keivan Navi 《ETRI Journal》2014,36(1):89-98
The integration of digital circuits has a tight relation with the scaling down of silicon technology. The continuous scaling down of the feature size of CMOS devices enters the nanoscale, which results in such destructive effects as short channel effects. Consequently, efforts to replace silicon technology with efficient substitutes have been made. The carbon nanotube field‐effect transistor (CNTFET) is one of the most promising replacements for this purpose because of its essential characteristics. Various digital CNTFET‐based circuits, such as standard logic cells, have been designed and the results demonstrate improvements in the delay and energy consumption of these circuits. In this paper, a new CNTFET‐based 5‐input XOR gate based on a novel design method is proposed and simulated using the HSPICE tool based on the compact SPICE model for the CNTFET at the 32‐nm technology node. The proposed method leads to improvements in performance and device count compared to the conventional CMOS‐style design. 相似文献
102.
Fariba Azadi Kenari Samira Moniri Davoud Dorranian Mahmood Ghoranneviss 《Journal of Modern Optics》2018,65(8):899-906
Tantalum nanoparticles (Ta NPs) were synthesized in ethanol solution by ablation with a 1064 nm Nd:YAG laser. Prepared NPs were investigated by UV-visible absorption spectroscopy, Transmission electron microscopy, X-ray diffraction and Photoluminescence measurement. The average sizes of NPs were calculated to be in the range of 12–18 nm. From the UV-visible studies, the plasmon peak position of Ta NPs was observed in the spectral range of 206–208 nm. The XRD spectra clearly showed the crystalline structure of NPs and various peaks of Ta and Ta2O5. Moreover, the UV region in the PL spectrum included the free exciton and the bound exciton emission correlated with the defect concentration. In fact, the laser ablation in the organic and inorganic solvents is a strong technique to obtain some NPs with particular structures, which are impossible to produce by conventional methods. 相似文献
103.
Many studies have recently been conducted on the evaluation of system performance with a two‐stage network structure in data envelopment analysis (DEA) literature. One of the topics of interest to researchers has been the mitigation of undesirable products or nondiscretionary factors into their corresponding possible production set (PPS) and their impact on overall efficiency calculations. Determination of decision‐making units (DMUs) with Pareto–Koopmans efficiency status is decisive in identifying benchmark units. The calculated overall efficiency status is compromised when both undesirable products and nondiscretionary factors are present. This work utilizes an axiomatic approach. A novel PPS for a two‐stage network in presence of undesirable intermediate products and nondiscretionary exogenous inputs is introduced. Based on this PPS and by focusing on the principle of mathematical dominance, new models for evaluating overall and divisional efficiencies are presented. In addition, by proposing a two‐step network DEA approach, a necessary and sufficient condition for detection of DMUs with Pareto–Koopmans efficiency status is provided. And by introducing a two‐step algorithm, a novel technique for determining overall efficiency conditions is produced. Finally, the proposed technology is applied to a practical example, and outcomes are discussed. 相似文献
104.
There are different approaches to modelling the products at the End of Life (EOL), including closed loop approach, the ladder of lansink and material flow. The sustainability principles and the complexity of the products may affect the choice of modelling type. The life cycle costs, several subsystems and the interaction between design features, construction, technology, suppliers and legislation affect the degree of complexity of the products. Hence, developing appropriate strategies are required for modelling EOL phase of the complex products. This article presents strategies for modelling EOL phase of complex products considering sustainability tools, EOL phase models and the characteristics of these products. An ingenerated approach is proposed to address the four essential aspects of the complex product at the EOL: operational, tactical, strategic and sustainability. The case of aircraft at the EOL is presented to highlight the application of the proposed approach. 相似文献
105.
Social aspects of a community may be correlated with driver's involvement in road traffic accidents. This study focused on examining this association in the context of the social capital theory. A survey of 600 Arab drivers living in 19 towns and villages was conducted using a face-to-face interview. Structural equation modeling was applied to explore paths of associations between the model components. Most of the proposed relationships in the path model were found to be significant, where the model explained 37% of the variation. The results indicate that only volunteering and reciprocity have direct correlations with traffic law violations. While the other correlations (except political involvement), were mediated by attitudes toward traffic laws violation. 相似文献
106.
Samira Mohamed Rabie S. El-Ghanem Nazeha 《Journal of Infrared, Millimeter and Terahertz Waves》2001,22(6):941-960
The temperature induced changes in the intensities of the infrared absorption bands of PVA in both MID and NIR regions are presented. The absorption band at 1141cm-1 is the only band among the bands in the mid region which is markedly affected by temperature. This band is taken as a measure of crystallinity of PVA. PVA shows two phase transitions at 80c0 and 120c0. The absorbances of the 1940nm in the near region is also temperature sensititve. The temperature dependence of the other bands in either mid or near regions is very weak. The effect of non polar and polar solvents such as n-hexane, carbon tetrachloride, toluene, chloroform, methanol and acetone is discussed. Comparison between the solvent induced changes in the intensities of the bands in mid and near regions is carried out. The data demonstrate that the bands in the near region ( overtone and combinations) are more sensitive to solvents than the bands in the mid regions. The combined effect of temperature and solvents on the intensities of absorption bands of PVA is also studied. 相似文献
107.
Experimental results regarding reaction rate profiles and final latex and polymer properties are presented for combinations of four different RAFT agents [benzyl dithioacetate (BDA), benzyl dithiobenzoate (BDB), 1-phenyl ethyl dithiobenzoate (PhEDB), and cumyl dithiobenzoate (CDB)] and three types of initiators [potassium peroxodisulfate (KPS), 4,4′-azobis (4-cyanopentanoic acid) (ACPA), and poly(ethylene glycol)-azo-initiator (PEGA200)]. It was found out that at given type of RAFT agent the type of initiator has a strong influence on the reaction rate profiles as well as on both the molecular properties of the polymers and the colloidal properties of the latexes. Among the RAFT agents tested BDA is the most efficient one regarding the control of chain growth. 相似文献
108.
Bouziane Mahmah Farid Harouadi H. Benmoussa Samira Chader Maïouf Belhamel Abdelhamid M'Raoui Kamel Abdeladim Adel Nasser Cherigui Claude Etievant 《International Journal of Hydrogen Energy》2009,34(11):4922-4933
Mediterranean Hydrogen Solar (MedHySol) is a federator project for development of a massive hydrogen production starting from solar energy and its exportation within a framework of a Euro–Maghrebian Cooperation project for industrial and energetic needs in the Mediterranean basin. The proposal of this project is included in the Algiers Declaration's on Hydrogen from Renewable Origin following the organization of the first international workshop on hydrogen which was held in 2005. Algeria is the privileged site to receive the MedHySol platform. The objective of the first step of the project is to realize a technological platform allowing the evaluation of emergent technologies of hydrogen production from solar energy with a significant size (10–100 kW) and to maintain the development of energetic rupture technologies. The second step of the project is to implement the most effective and less expensive technologies to pilot great projects (1–1000 MW). In this article we present the potentialities and the feasibility of MedHySol, as well as the fundamental elements for a scientific and technical supervision of this great project. 相似文献
109.
In this paper, a recursive hierarchical parametric estimation (RHPE) algorithm is proposed for stochastic nonlinear systems which can be described by Wiener‐Hammerstein (W‐H) mathematical models. The formulation of parameters estimation problem is based on the prediction error approach and the gradient techniques. The convergence analysis of the developed RHPE algorithm is derived using stochastic gradient‐based theory. Wiener‐Hammerstein hydraulic process is treated to prove the efficiency of the proposed approach. 相似文献
110.
John W. F. To Jia Wei Desmond Ng Samira Siahrostami Ai Leen Koh Yangjin Lee Zhihua Chen Kara D. Fong Shucheng Chen Jiajun He Won-Gyu Bae Jennifer Wilcox Hu Young Jeong Kwanpyo Kim Felix Studt Jens K. Nørskov Thomas F. Jaramillo Zhenan Bao 《Nano Research》2017,10(4):1163-1177
The development of high-performance and low-cost oxygen reduction and evolution catalysts that can be easily integrated into existing devices is crucial for the wide deployment of energy storage systems that utilize O2-H2O chemistries,such as regenerative fuel cells and metal-air batteries.Herein,we report an NH3-activated N-doped hierarchical carbon (NHC) catalyst synthesized via a scalable route,and demonstrate its device integration.The NHC catalyst exhibited good performance for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER),as demonstrated by means of electrochemical studies and evaluation when integrated into the oxygen electrode of a regenerative fuel cell.The activities observed for both the ORR and the OER were comparable to those achieved by state-of-the-art Pt and Ir catalysts in alkaline environments.We have further identified the critical role of carbon defects as active sites for electrochemical activity through density functional theory calculations and high-resolution TEM visualization.This work highlights the potential of NHC to replace commercial precious metals in regenerative fuel cells and possibly metal-air batteries for cost-effective storage of intermittent renewable energy. 相似文献