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221.
Low Cost,Low Power Magnetic IEDs Detection Method Using Biaxial Magnetometry Digital Sensors 下载免费PDF全文
The magnetic improvised explosive devices (IEDs), also commonly known as a type of a sticky bomb, is simply constructed devices yet very lethal. This paper puts forward the idea of an electronic compass that is capable of sensing the change of a magnetic field generated by a magnet and translating it into interpretable data, which could act as the base for the further studies and assist in developing a greener automated system for detecting this device. The electronic compass is specifically chosen for reducing power consumption of systems in addition to the fact that it is available at a low cost. 相似文献
222.
Manawwer Alam Naser M. Alandis Naushad Ahmad 《International Journal of Polymer Analysis and Characterization》2017,22(4):281-293
Corn oil-based poly(urethane-ester)amide was synthesized from corn oil-based fatty amide diol, camphoric acid, and tolylene 2,4-diisocyanate. The structure of corn polyesteramide and corn poly(urethane-ester)amide (CPEA) was confirmed by Fourier transform infrared, 1H NMR, and 13C NMR spectroscopic techniques. CPUEA coatings were made on mild steel strips and their physicomechanical analysis (scratch hardness, impact test, conical mandrel test, and pencil hardness tests) was performed by standard methods. The surface morphology of coatings was observed by scanning electron microscopy and thermal stability was assessed by thermogravimetric analysis/differential scanning calorimetry. Anticorrosion properties of CPUEA were observed in acidic, saline, and tap water medium at room temperature using potentiodynamic polarization technique. The results of CPUEA coatings exhibit good physicomechanical and anticorrosive properties and can find application up to 175°C. 相似文献
223.
Mohamed Abd Elaziz Abdelghani Dahou Naser A. Alsaleh Ammar H. Elsheikh Amal I. Saba Mahmoud Ahmadein 《Entropy (Basel, Switzerland)》2021,23(11)
Currently, the world is still facing a COVID-19 (coronavirus disease 2019) classified as a highly infectious disease due to its rapid spreading. The shortage of X-ray machines may lead to critical situations and delay the diagnosis results, increasing the number of deaths. Therefore, the exploitation of deep learning (DL) and optimization algorithms can be advantageous in early diagnosis and COVID-19 detection. In this paper, we propose a framework for COVID-19 images classification using hybridization of DL and swarm-based algorithms. The MobileNetV3 is used as a backbone feature extraction to learn and extract relevant image representations as a DL model. As a swarm-based algorithm, the Aquila Optimizer (Aqu) is used as a feature selector to reduce the dimensionality of the image representations and improve the classification accuracy using only the most essential selected features. To validate the proposed framework, two datasets with X-ray and CT COVID-19 images are used. The obtained results from the experiments show a good performance of the proposed framework in terms of classification accuracy and dimensionality reduction during the feature extraction and selection phases. The Aqu feature selection algorithm achieves accuracy better than other methods in terms of performance metrics. 相似文献
224.
M. Naser Shafin 《Mathematical Notes》1978,23(6):461-463
A local uniqueness theorem and analogs of the theorem on removable singularities under the hypothesis of boundedness are proved for functions satisfying the tangential Cauchy-Riemann conditions on hypersurfaces in Cn. The results can be interpreted as giving certain boundary properties of holomorphic functions of several complex variables.Translated from Matematicheskie Zametki, Vol. 23, No. 6, pp. 839–844, June, 1978.In conclusion I express my thanks to B. V. Shabat for his contant interest in this work. 相似文献
225.
226.
Monte Carlo computer simulation is used to follow the adsorption of a model globular and disordered protein at a hard surface and to simulate the surface equation of state for these molecules. The simulation utilizes the deformable globule model where the "protein" is treated as a collection of interacting subunits. Disordered globules are modeled as athermal molecules, whereas globular molecules have a strong attractive interaction between subunits. The surface equation of state is modeled by applying a known pressure to an adsorbed globule and following the changes in adsorbed conformation. Simulated equations of state for the disordered and globular molecules show features that are observed in experimental surface pressure versus area plots. In particular the simulated equations of state show "kinks" that correspond to regions where the adsorbed globules undergo conformational changes as they lift away from the surface in response to the increased pressure. The model proteins follow Bull's equation at low surface pressures in a way that is broadly in line with results from experiment, and the changes in conformation as a function of surface pressure are in line with predictions by DeFeijter and Benjamins made using a soft-particle model for adsorbed proteins. 相似文献
227.
We used dilute solution viscometry, specifically, measurements of intrinsic viscosity and overlap concentration to characterize two members of the carbopol family, carbopols 940 and 941. These measured quantities were then used to calculate the swollen-to-dry volume ratios for both resins over a range of ionic strengths. The variation in this ratio is representative of the swelling equilibria of the micronetwork and is modeled using standard network theory with modifications for non-Gaussian chain statistics and for fixed charges on the chains. By fitting to experimental data, the cross-link density is determined as 1450 monomer units between cross-link sites for carbopol 940 and 3300 units for carbopol 941. The shear modulus of the microgel domain is then predicted from the swelling data and found to be an order of magnitude greater than the elastic modulus measured on concentrated carbopol dispersions. We argue that this discrepancy is due to a large number of defects which reduce the cycle rank of the network. Current microgel technology specifies that their rheological behavior can be predicted once the domain cross-link density is known. Simple dilute solution viscometry appears capable of providing this prerequisite. 相似文献
228.
L. Declan Burke Nageb S. Naser Bernadette M. Ahern 《Journal of Solid State Electrochemistry》2007,11(5):655-666
Hydrous iridium oxide films are highly resistant to reduction under cathodic, hydrogen gas evolution, conditions in aqueous
acid or base. Such behavior is not in agreement with simple thermodynamic (Pourbaix) data based on the assumption that the
system behaves in a reversible manner. The barrier to reduction is attributed, as discussed earlier for RuO2, to the involvement of high-energy intermediates (iridium atoms or microclusters of same) which can only be generated at
unusually negative overpotential values evidently far into the hydrogen gas evolution region. Thermally prepared IrO2/Ti electrodes are possible candidates for hydrogen gas evolution cathodes in water electrolysis cells; however, under extended
operating conditions, the performance of these cathodes was found to deteriorate due to gradual shedding of the active oxide
layer. 相似文献
229.
Fernando S. Campos Ognian Marinov Naser Faramarzpour Fayçal Saffih M. Jamal Deen Jacobus W. Swart 《Analog Integrated Circuits and Signal Processing》2008,57(1-2):151-159
A novel multisampling time-domain architecture for CMOS imagers with synchronous readout and wide dynamic range is proposed. The proposed multisampling architecture requires only a single bit per pixel memory instead of 8 bits which is typical for time-domain active pixel architectures. The goal is to obtain a time-domain imager with high dynamic range that requires lower number of transistors per pixel in order to achieve higher fill-factor. The maximum frame rate is analyzed as a function of number of bits and array size. The analysis shows that it is possible to achieve high frame rates and operate in video mode having 10 bit pixel data resolution. Also, we present analysis of the impact of comparator offset voltage on the fixed pattern noise. The architecture was implemented in an imager prototype with 32 × 32 pixel array fabricated in AMS CMOS 0.35 μm and was characterized for sensitivity, noise and color response. The pixel size is 30 μm × 26 μm and it is composed of an n+/psub photodiode, a comparator and a D flip-flop with a 16% fill-factor. 相似文献
230.