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排序方式: 共有195条查询结果,搜索用时 15 毫秒
71.
The drilling of a number of boreholes to determine the soil profile of a given area is time consuming and costly. This paper
describes estimated soil profiles obtained using a model based on artificial neural networks (ANN). ANN is a powerful data-modelling
tool capable of capturing and representing complex relationships between input and output. It deals with many multi-variate
problems for which an exact analytical model does not exist or is very difficult and time consuming to develop. The main settlement
in the Adapazari region was selected to demonstrate the capability of such model. The results obtained using ANN are promising
when compared with the soil profile obtained from boreholes.
相似文献
72.
Che Sidik Nor Azwadi Mohammadjavad Zeinali Arman Safdari Alieh Kazemi 《Numerical Heat Transfer, Part A: Applications》2013,63(12):906-920
Heat transfer behavior in a 2-D square lid-driven cavity has been studied for various pertinent Reynolds and Rayleigh numbers. The lattice Boltzmann method, a numerical tool based on the particle distribution function is applied to simulate a thermal fluid flow problem. Bhatnagar-Gross-Krook (BGK) is combined with the double population thermal Lattice Boltzmann model to solve mixed convection in a square cavity. An adaptive-network-based fuzzy inference system (ANFIS) method is trained and validated using BGK Lattice Boltzmann model results. The results show that the trained ANFIS model successfully predicts the temperature and flow fields in a few seconds with acceptable accuracy. 相似文献
73.
Shikhgasan Ramazanov Dinara Sobola Ştefan Ţălu Farid Orudzev Ali Arman Pavel Kaspar Rashid Dallaev Guseyn Ramazanov 《Microscopy research and technique》2022,85(4):1300-1310
Thin films of bismuth and iron oxides were obtained by atomic layer deposition (ALD) on the surface of a flexible substrate poly(4,4′-oxydiphenylene-pyromellitimide) (Kapton) at a temperature of 250°C. The layer thickness was 50 nm. The samples were examined by secondary-ion mass spectrometry, and uniform distribution of elements in the film layer was observed. Surface morphology, electrical polarization, and mechanical properties were investigated by atomic force microscope, piezoelectric force microscopy, and force modulation microscopy. The values of current in the near-surface layer varied in the range of ±80 pA when a potential of 5 V was applied. Chemical analysis was performed by X-ray photoelectron spectroscopy, where the formation of Bi2O3 and Fe2O3 phases, as well as intermediate phases in the Bi–Fe–O system, was observed. Magnetic measurements were carried out by a vibrating sample magnetometer that showed a ferromagnetic response. The low-temperature method of functionalization of the Kapton surface with bismuth and iron oxides will make it possible to adapt the Bi–Fe–O system to flexible electronics. 相似文献
74.
Rubayyat Mahbub Takian Fakhrul Md. Fakhrul Islam Mehedi Hasan Arman Hussain M.A. Matin M.A. Hakim 《金属学报(英文版)》2015,28(8):958
The main focus of the research was to correlate the microstructure with dielectric and magnetic properties of Bi1-xBaxFeO3 samples. Bi1-xBaxFeO3 samples(x = 0.1, 0.2 and 0.3) were synthesized by the conventional solid-state reaction method using nano-powders of Bi2O3, Fe2O3, and BaCO3. Thereafter, field emission scanning electron microscope and X-ray diffraction(XRD) techniques were used to examine the structure and phase of the samples. Phase analysis by XRD indicated that the single-phase perovskite structure was formed with possible increment in lattice parameter with increasing Ba doping. Complex permeability(u'iand u'i) measured using impedance analyzer confirmed the increase in magnetic property with increasing Ba doping. Finally, dielectric constant(k) was analyzed as a function of temperature at different frequencies. Dielectric constant as high as 2900 was attained in this research for Bi0.8Ba0.2FeO3 sample due to reduction in leakage current at this composition. 相似文献
75.
Arman Siahvashi Adesoji A. Adesina 《International Journal of Hydrogen Energy》2018,43(36):17195-17204
Carbon deposition during carbon dioxide reforming reaction of C3H8 has been studied over alumina-supported bimetallic Mo/CoNi catalysts. To better understand the carbon-induced deactivation during the reforming reaction, changes in catalyst morphology and carbon deposition kinetics were examined. Different characterization techniques were used for both fresh and rejuvenated catalysts including liquid nitrogen adsorption/desorption, chemisorption via hydrogen, ammonia and CO2 desorption, and thermogravimetric measurement of the coked catalysts. The time dependant reaction rate profiles indicated that MoNi catalyst has higher syngas (H2/CO) formation rates with lower CO2 rate of consumption compared to CoNi catalyst. However, the H2:CO ratio values were almost the same for both catalysts suggesting similarity in the product formation pathway. Conversion-time analysis showed that MoNi catalyst was more stable and active during a 72-h run while CoNi suffered noticeable deactivation after 30 h on-stream. Reaction-deactivation models implicated a higher deactivation coefficient (kd) with activation energy of Ed = 78.1 kJ mol?1 for the cobalt-containing Ni catalyst, while the Ni catalyst with molybdenum had a lower deactivation coefficient with smaller activation energy of just under 70 kJ mol?1. Post-mortem analysis (TPR-TPO dual cycle and TOC) of spent catalysts confirmed that the surface of CoNi catalyst has more carbon residue than the MoNi sample which was consistent with the higher deactivation of CoNi. 相似文献
76.
Mahiye Uluyagmur Ozturk Ayse Rodopman Arman Gresa Carkaxhiu Bulut Onur Tugce Poyraz Findik Sultan Seval Yilmaz Herdem Aslan Genc M. Yanki Yazgan Umut Teker Zehra Cataltepe 《Intelligent Automation and Soft Computing》2018,24(4):891-905
Emotion recognition behavior and performance may vary between people with major
neurodevelopmental disorders such as Autism Spectrum Disorder (ASD), Attention Deficit
Hyperactivity Disorder (ADHD) and control groups. It is crucial to identify these differences
for early diagnosis and individual treatment purposes. This study represents a
methodology by using statistical data analysis and machine learning to provide help to
psychiatrists and therapists on the diagnosis and individualized treatment of participants
with ASD and ADHD. In this paper we propose an emotion recognition experiment
environment and collect eye tracker fixation data together with the application log data
(APL). In order to detect the diagnosis of the participant we used classification algorithms
with the Tomek links noise removing method. The highest classification accuracy results
were reported as 86.36% for ASD vs. Control, 81.82% for ADHD vs. Control and 70.83%
for ASD vs. ADHD. This study provides evidence that fixation and APL data have
distinguishing features for the diagnosis of ASD and ADHD. 相似文献
77.
Arman Sadeghi Mohammad Hassan Saidi 《International Journal of Heat and Mass Transfer》2010,53(19-20):3782-3791
This study investigates the influence of viscous dissipation on thermal transport characteristics of the fully developed combined pressure and electroosmotically driven flow in parallel plate microchannels subject to uniform wall heat flux. Closed form expressions are obtained for the transverse distributions of electrical potential, velocity and temperature and also for Nusselt number. From the results it is realized that the Brinkman number has a significant effect on Nusselt number. Generally speaking, to increase Brinkman number is to decrease Nusselt number. Although the magnitude of Joule heating can affect Brinkman number dependency of Nusselt number, however the general trend remains unchanged. Depending on the value of flow parameters, a singularity may occur in Nusselt number values even in the absence of viscous heating, especially at great values of dimensionless Joule heating term. For a given value of Brinkman number, as dimensionless Debye–Huckel parameter increases, the effect of viscous heating increases. In this condition, as dimensionless Debye–Huckel parameter goes to infinity, the Nusselt number approaches zero, regardless of the magnitude of Joule heating. Furthermore, it is realized that the effect of Brinkman number on Nusselt number for pressure opposed flow is more notable than purely electroosmotic flow, while the opposite is true for pressure assisted flow. 相似文献
78.
Accurate event-driven motion compensation in high-resolution PET incorporating scattered and random events 总被引:2,自引:0,他引:2
Rahmim A Dinelle K Cheng JC Shilov MA Segars WP Lidstone SC Blinder S Rousset OG Vajihollahi H Tsui BM Wong DF Sossi V 《IEEE transactions on medical imaging》2008,27(8):1018-1033
79.
Nasrollah Eslamzadeh Reza Ebrahimi-Kahrizsangi Saeed Karbasi Arman Zarebidaki Farhad Gharavi 《Journal of Materials Engineering and Performance》2017,26(9):4255-4264
Plasma electrolytic oxidation (PEO) of AZ91 Mg alloys was performed in ZrO2 nanoparticles containing Na2SiO3-based electrolytes. The phase composition and the microstructure of PEO coatings were analyzed by x-ray diffraction and scanning electron microscopy followed by energy dispersive spectroscopy. Pitting corrosion properties of the coatings were investigated using cyclic polarization and electrochemical impedance spectroscopy tests in a Ringer solution. The results showed the better pitting corrosion resistance of the composite coating, as compared to the oxide one, due to the thickened inner layer and the decrease in the surface defects of the composite coating. Also, the PEO process decreased the corrosion current density from 25.06 µA/cm2 in the Mg alloy to 2.7 µA/cm2 in the oxide coating and 0.47 µA/cm2 in the composite coating. 相似文献
80.