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31.
Heydari P. Pedram M. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2003,11(2):180-193
This paper is concerned with the analysis and optimization of the ground bounce in digital CMOS circuits. First, an analytical method for calculating the ground bounce is presented. The proposed method relies on accurate models of the short-channel MOS device and the chip-package interface parasitics. Next the effect of ground bounce on the propagation delay and the optimum tapering factor of a multistage buffer is discussed and a mathematical relationship for total propagation delay in the presence of the ground bounce is obtained. Effect of an on-chip decoupling capacitor on the ground bounce waveform and circuit speed is analyzed next and a closed form expression for the peak value of the differential-mode component of the ground bounce in terms of the on-chip decoupling capacitor is provided. Finally, a design methodology for controlling the switching times of the output drivers to minimize the ground bounce is presented. 相似文献
32.
S.?Ghashghaie A.?M.?Bazargan M.?Esmaeilpour?Ganji E.?MarzbanradEmail author C.?Zamani B.?Raissi M.?Keyanpour-rad M.?A.?Bahrevar 《Journal of Materials Science: Materials in Electronics》2011,22(9):1303-1307
In present study, the behavior of electrospun ZnO nanofibers under the application of low frequency alternating (AC) electric
fields within the range of 1 Hz–20 kHz was investigated using planar parallel electrodes. In the first stage, ZnO nanofibers
with diameters up to 100 nm were prepared by electrospinning. At 1 Hz, the strong electric field-induced fluid flow due to
charge redistribution around the electrode swept the fibers on the electrode surface farther from the edges. As the frequency
was increased to 1 kHz, most depositing fibers accumulated on the electrode edges and in the meantime, a small fraction of
them was pushed into the surface as a result of AC electroosmosis effect. Above 1 kHz, the fibers were assembled within the
electrode gap bridging the interelectrode space. The dielectrophoresis force was considered responsible for the assembly and
relative alignment of ZnO nanofibers above 1 kHz. 相似文献
33.
Anwer Mustafa Hilal Siwar Ben Haj Hassine Souad Larabi-Marie-Sainte Nadhem Nemri Mohamed K. Nour Abdelwahed Motwakel Abu Sarwar Zamani Mesfer Al Duhayyim 《计算机、材料和连续体(英文)》2022,72(1):713-726
The development in Information and Communication Technology has led to the evolution of new computing and communication environment. Technological revolution with Internet of Things (IoTs) has developed various applications in almost all domains from health care, education to entertainment with sensors and smart devices. One of the subsets of IoT is Internet of Medical things (IoMT) which connects medical devices, hardware and software applications through internet. IoMT enables secure wireless communication over the Internet to allow efficient analysis of medical data. With these smart advancements and exploitation of smart IoT devices in health care technology there increases threat and malware attacks during transmission of highly confidential medical data. This work proposes a scheme by integrating machine learning approach and block chain technology to detect malware during data transmission in IoMT. The proposed Machine Learning based Block Chain Technology malware detection scheme (MLBCT-Mdetect) is implemented in three steps namely: feature extraction, Classification and blockchain. Feature extraction is performed by calculating the weight of each feature and reduces the features with less weight. Support Vector Machine classifier is employed in the second step to classify the malware and benign nodes. Furthermore, third step uses blockchain to store details of the selected features which eventually improves the detection of malware with significant improvement in speed and accuracy. ML-BCT-Mdetect achieves higher accuracy with low false positive rate and higher True positive rate. 相似文献
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Alireza Ahmadiparidari Robert E. Warburton Leily Majidi Mohammad Asadi Amir Chamaani Jacob R. Jokisaari Sina Rastegar Zahra Hemmat Baharak Sayahpour Rajeev S. Assary Badri Narayanan Pedram Abbasi Paul C. Redfern Anh Ngo Mrton Vrs Jeffrey Greeley Robert Klie Larry A. Curtiss Amin Salehi‐Khojin 《Advanced materials (Deerfield Beach, Fla.)》2019,31(40)
Lithium–CO2 batteries are attractive energy‐storage systems for fulfilling the demand of future large‐scale applications such as electric vehicles due to their high specific energy density. However, a major challenge with Li–CO2 batteries is to attain reversible formation and decomposition of the Li2CO3 and carbon discharge products. A fully reversible Li–CO2 battery is developed with overall carbon neutrality using MoS2 nanoflakes as a cathode catalyst combined with an ionic liquid/dimethyl sulfoxide electrolyte. This combination of materials produces a multicomponent composite (Li2CO3/C) product. The battery shows a superior long cycle life of 500 for a fixed 500 mAh g?1 capacity per cycle, far exceeding the best cycling stability reported in Li–CO2 batteries. The long cycle life demonstrates that chemical transformations, making and breaking covalent C? O bonds can be used in energy‐storage systems. Theoretical calculations are used to deduce a mechanism for the reversible discharge/charge processes and explain how the carbon interface with Li2CO3 provides the electronic conduction needed for the oxidation of Li2CO3 and carbon to generate the CO2 on charge. This achievement paves the way for the use of CO2 in advanced energy‐storage systems. 相似文献
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Vahid Ghasemzadeh-mohammadi Bahman Zamani Maryam Afsharpour Abdorreza Mohammadi 《Food science and biotechnology》2017,26(5):1281-1290
In this research, optimal conditions for extraction of caffeine and polyphenols were established from Iranian green tea leaves. In the first step, caffeine was extracted with efficacy about 86% versed to 4.5% of EGC + EGCG. The EGCG + EGC was extracted from partially decaffeinated green tea leaves through microwave-assisted extraction (MAE) and ultrasound-assisted extraction (USE) with efficiency levels of 95 and 85%, respectively. The best results for the MAE process were obtained with 7.8 min and three number of extraction cycles and for the USE process were as followed: time 57 min, temperature 65 °C, and the number of extraction cycles 3. The total phenol content values at the best conditions of MAE and the USE processes were 125 ± 5 and 96 ± 6 mg gallic acid/g DW. The 50% inhibition (IC50) on 1,1-diphenyl-2-picrylhydrazyl (DPPH) were 56 and 66 mg/g of phenol for the MAE and USE processes. 相似文献
39.
Microsystem Technologies - An alternative actuator for MEMS/NEMS device is proposed and analyzed. The actuator is based on the paired-wires (PW) carrying current concept, which makes the actuator... 相似文献
40.
Shojae Chaeikar Saman Zamani Mazdak Abdul Manaf Azizah Bt Zeki Akram M. 《Multimedia Tools and Applications》2018,77(1):805-835
Multimedia Tools and Applications - Steganography is the art and science of producing covert communications by concealing secret messages in apparently innocent media, while steganalysis is the art... 相似文献