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Mesfer Al Duhayyim Jaber S. Alzahrani Hanan Abdullah Mengash Mrim M. Alnfiai Radwa Marzouk Gouse Pasha Mohammed Mohammed Rizwanullah Amgad Atta Abdelmageed 《计算机系统科学与工程》2023,46(2):1471-1485
The Internet of Things (IoT) environment plays a crucial role in the design of smart environments. Security and privacy are the major challenging problems that exist in the design of IoT-enabled real-time environments. Security susceptibilities in IoT-based systems pose security threats which affect smart environment applications. Intrusion detection systems (IDS) can be used for IoT environments to mitigate IoT-related security attacks which use few security vulnerabilities. This paper introduces a modified garden balsan optimization-based machine learning model for intrusion detection (MGBO-MLID) in the IoT cloud environment. The presented MGBO-MLID technique focuses on the identification and classification of intrusions in the IoT cloud atmosphere. Initially, the presented MGBO-MLID model applies min-max normalization that can be utilized for scaling the features in a uniform format. In addition, the MGBO-MLID model exploits the MGBO algorithm to choose the optimal subset of features. Moreover, the attention-based bidirectional long short-term (ABiLSTM) method can be utilized for the detection and classification of intrusions. At the final level, the Aquila optimization (AO) algorithm is applied as a hyperparameter optimizer to fine-tune the ABiLSTM methods. The experimental validation of the MGBO-MLID method is tested using a benchmark dataset. The extensive comparative study reported the betterment of the MGBO-MLID algorithm over recent approaches. 相似文献
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Michael Q. Wang Jeongwoo HanZia Haq Wallace E. TynerMay Wu Amgad Elgowainy 《Biomass & bioenergy》2011,35(5):1885-1896
Use of ethanol as a transportation fuel in the United States has grown from 76 dam3 in 1980 to over 40.1 hm3 in 2009 — and virtually all of it has been produced from corn. It has been debated whether using corn ethanol results in any energy and greenhouse gas benefits. This issue has been especially critical in the past several years, when indirect effects, such as indirect land use changes, associated with U.S. corn ethanol production are considered in evaluation. In the past three years, modeling of direct and indirect land use changes related to the production of corn ethanol has advanced significantly. Meanwhile, technology improvements in key stages of the ethanol life cycle (such as corn farming and ethanol production) have been made. With updated simulation results of direct and indirect land use changes and observed technology improvements in the past several years, we conducted a life-cycle analysis of ethanol and show that at present and in the near future, using corn ethanol reduces greenhouse gas emission by more than 20%, relative to those of petroleum gasoline. On the other hand, second-generation ethanol could achieve much higher reductions in greenhouse gas emissions. In a broader sense, sound evaluation of U.S. biofuel policies should account for both unanticipated consequences and technology potentials. We maintain that the usefulness of such evaluations is to provide insight into how to prevent unanticipated consequences and how to promote efficient technologies with policy intervention. 相似文献
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Mohamed Mahmoud Nasef Ezzatollah Shamsaei Payman Ghassemi Amgad Ahmed Aly Abdul Hamid Yahaya 《应用聚合物科学杂志》2013,127(3):1659-1666
The traditional method for obtaining best combination of reaction parameters for graft copolymerization of 4‐vinylpyridine onto poly(vinylidene fluoride) films was modified using Box‐Behnken factorial design available in the response surface method (RSM). A computer‐assisted statistical simulator was used to obtain the optimum absorbed dose, monomer concentration, grafting time and reaction temperature to achieve the highest degree of grafting (G%) based a quadratic model. The validity of the developed model was confirmed by experimental data, which only deviated by a 2% from the predicted value of G% confirming the effectiveness of RSM in optimization of the reaction parameters in the present grafting system. A comparison was also made between the obtained model and that of 1‐vinylimidazole/poly(ethylene‐co‐tetrafluoroethylene) grafting system. The chemical structure, morphology and thermal stability of the obtained graft copolymers was investigated by means of Fourier transform infrared, filed emission scanning electron microscope, and thermogravimetric analysis, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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S. Lee S. H. Saw R. S. Rawat P. Lee R. Verma A. Talebitaher S. M. Hassan A. E. Abdou Mohamed Ismail Amgad Mohamed H. Torreblanca Sh. Al Hawat M. Akel P. L. Chong F. Roy A. Singh D. Wong K. Devi 《Journal of Fusion Energy》2012,31(2):198-204
The fast pulsed electric discharge current drives all physical processes in the plasma focus device; in turn all physical processes in the focus affect the current waveform. Thus the discharge current waveform is the most important indicator of plasma focus performance. This underlies the importance of properly measuring, processing and interpreting the discharge current waveform. This paper reports the measurement of fast pulsed discharge current by the Rogowski coil, in two different modes: the current transformer, ??I?? mode, and current derivative, ??Idot?? mode. The processing and interpretation of recorded current waveform to obtain useful information about the physical processes in the plasma focus device are discussed. The current transformer with a large number of turns and a sub-1 Ohm terminator has good high frequency response, necessary for the sharp current dip region when dI/dt exceeds 2?×?1011?A/s. However the signal is ??noisy?? in the current dip region. Several methods to extract the current dip from the noise are discussed and examples of how low pass filters affect the signals are shown. The dI/dt coil, the Rogowski coil in ??Idot?? mode, with a few turns terminated by 50-Ohm is also described. Integrating the 1?GSa/s digital waveform does remove the high frequency noise components, yet the extracted waveform shows sharp angular features indicative of the retention of short-time features. This makes the dI/dt coil superior to the current transformer. A 7-turn coil is tested against the Lee Model code and found to be suitable to measure the plasma focus discharge current. 相似文献
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Steam crackers convert hydrocarbon feedstock (e.g., natural gas liquids) to light olefins via thermal cracking and produce hydrogen as a by-product during the process. Benefiting from the shale gas boom in recent years, the overall production capacity of U.S. steam crackers, as well as the potential of by-product hydrogen production, is continuously growing. We estimate that 3.5 million tonne/year of by-product hydrogen can be produced from steam crackers, almost doubling the size of the existing U.S. merchant hydrogen market. We also find that producing hydrogen from steam crackers creates less (15%–91%) life-cycle greenhouse gas emissions than the conventional centralized steam methane reforming (SMR) pathway. For criteria air pollutants, life-cycle emissions reduction benefits vary greatly (?75% – +85%), depending on the co-product treatment scenario (substitution or allocation) and air pollutant type. The substitution scenario generally results in an increase of criteria air pollutants emissions, mainly due to the requirement of substitutive natural gas fuel. We estimate that the cost of purified by-product hydrogen fuel from steam crackers is $0.9–1.1/kg, reducing hydrogen production costs by 30% compared to the conventional central SMR pathway. Furthermore, using by-product hydrogen from steam crackers can generate credits of $1.8–2.5/kg under California's low-carbon fuel standard. 相似文献
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Sameh S. Badie Amgad F. Morgan Girgis Maher K. Tadros Nghi T. Nguyen 《Canadian Metallurgical Quarterly》2010,15(5):482-492
The AASHTO LRFD Bridge Design Specifications state that the spacing between the shear connectors for steel girders should not exceed 610 mm (24 in.). This decision was made based on research conducted more than three decades ago. The goal of this research is to investigate the possibility of extending this limit to 1,220 mm (48 in.) for stud clusters used with full-depth precast concrete deck panels installed on steel girders. This paper presents the history of the 610 mm (24 in.) limit, various formulas developed to calculate fatigue and design capacity for stud clusters and concerns about extending the current LRFD limit. This paper also presents information on the first phase of the experimental investigation, which is conducted on push-off specimens to validate extending the limit to 1,220 mm (48 in.). 相似文献
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Krishna Reddi Amgad Elgowainy Neha Rustagi Erika Gupta 《International Journal of Hydrogen Energy》2017,42(34):21855-21865
The cost of hydrogen in early fuel cell electric vehicle (FCEV) markets is dominated by the cost of refueling stations, mainly due to the high cost of refueling equipment, small station capacities, lack of economies of scale, and low utilization of the installed refueling capacity. Using the hydrogen delivery scenario analysis model (HDSAM), this study estimates the impacts of these factors on the refueling cost for different refueling technologies and configurations, and quantifies the potential reduction in future hydrogen refueling cost compared to today's cost in the United States. The current hydrogen refueling station levelized cost, for a 200 kg/day dispensing capacity, is in the range of $6–$8/kg H2 when supplied with gaseous hydrogen, and $8–$9/kg H2 for stations supplied with liquid hydrogen. After adding the cost of hydrogen production, packaging, and transportation to the station's levelized cost, the current cost of hydrogen at dispensers for FCEVs in California is in the range of $13–$15/kg H2. The refueling station capacity utilization strongly influences the hydrogen refueling cost. The underutilization of station capacity in early FCEV markets, such as in California, results in a levelized station cost that is approximately 40% higher than it would be in a scenario where the station had been fully utilized since it began operating. In future mature hydrogen FCEV markets, with a large demand for hydrogen, the refueling station's levelized cost can be reduced to $2/kg H2 as a result of improved capacity utilization and reduced equipment cost via learning and economies of scale. 相似文献
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Edward D. Frank Amgad Elgowainy Krishna Reddi Adarsh Bafana 《International Journal of Hydrogen Energy》2021,46(43):22670-22683
The cost of hydrogen delivery for transportation accounts for most of the current H2 selling price; delivery also requires substantial amounts of energy. We developed harmonized techno-economic and life-cycle emissions models of current and future H2 production and delivery pathways. Our techno-economic analysis of dispensed H2 costs guided our selection of pathways for the life-cycle analysis. In this paper, we present the results of market expansion scenarios using existing capabilities (for example, those that use H2 from steam methane reforming, chlor-alkali, and natural gas liquid cracker plants), as well as results for future electrolysis plants that use nuclear, solar, and hydroelectric power. Reductions in greenhouse gas emissions for fuel cell electric vehicles compared to conventional gasoline pathways vary from 40% reduction for fossil-derived H2 to 20-fold for clean H2. Supplemental tables with greenhouse gas emissions data for each step in the H2 pathways enable readers to evaluate additional scenarios. 相似文献