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11.
Mukesh Kumar Sk Nurul Islam Gobinda Sen Susanta Kumar Parui Santanu Das 《国际射频与微波计算机辅助工程杂志》2020,30(7)
This letter presents a filtering directional coupler (FDC) with enhanced coupling and high directivity simultaneously. The proposed FDC is composed of a pair of coupled lines instead transmission line of a directional coupler. This coupled lines resonator increases the design parameters by which even/odd mode phase velocity can be compensated to improve the directivity and coupling level. The coupling enhancement can be explained by analyzing the even mode and odd mode circuit of the proposed coupler. A prototype of the proposed coupler is designed which provides a high directivity of 44 dB for 6 dB coupling level at 1 GHz frequency. The proposed coupler is designed, fabricated, and tested. 相似文献
12.
Kuldeep Chouhan Mukesh Yadav Ranjeet Kumar Rout Kshira Sagar Sahoo NZ Jhanjhi Mehedi Masud Sultan Aljahdali 《计算机系统科学与工程》2023,45(2):1113-1128
Twitter is a radiant platform with a quick and effective technique to analyze users’ perceptions of activities on social media. Many researchers and industry experts show their attention to Twitter sentiment analysis to recognize the stakeholder group. The sentiment analysis needs an advanced level of approaches including adoption to encompass data sentiment analysis and various machine learning tools. An assessment of sentiment analysis in multiple fields that affect their elevations among the people in real-time by using Naive Bayes and Support Vector Machine (SVM). This paper focused on analysing the distinguished sentiment techniques in tweets behaviour datasets for various spheres such as healthcare, behaviour estimation, etc. In addition, the results in this work explore and validate the statistical machine learning classifiers that provide the accuracy percentages attained in terms of positive, negative and neutral tweets. In this work, we obligated Twitter Application Programming Interface (API) account and programmed in python for sentiment analysis approach for the computational measure of user’s perceptions that extract a massive number of tweets and provide market value to the Twitter account proprietor. To distinguish the results in terms of the performance evaluation, an error analysis investigates the features of various stakeholders comprising social media analytics researchers, Natural Language Processing (NLP) developers, engineering managers and experts involved to have a decision-making approach. 相似文献
13.
Abhay Kumar Singh Mukesh K. Mahato Babita Neogi K. K. Singh 《Mine Water and the Environment》2010,29(4):248-262
In a qualitative assessment of mine water from the Raniganj coalfield, 77 mine water samples were analyzed to assess water
quality and suitability for domestic, industrial, and irrigation uses. The pH of the mine water ranged from 6.5 to 8.8. Total
dissolved solids (TDS) ranged from 171 to 1,626 mg L−1; spatial differences between the TDS values reflect variations in lithology, activities, and prevailing hydrological regime.
The anion chemistry was dominated by HCO3
− and SO4
2−. On average, Cl− contributes 10 and 19% of the total anionic balance, respectively, in the Barakar and Raniganj Formation mine water. F− and NO3
− contribute <2% to the total anions. The cation chemistry is dominated by Mg2+ and Ca2+ in the mine water of the Barakar Formation and Na+ in the Raniganj Formation mines. Much of the mine water, especially of the Barakar Formation area, has high TDS, total hardness,
and SO4 concentrations. Concentrations of some trace metals (i.e. Fe, Cr, Ni) were found to be above the levels recommended for drinking
water. However, the mine water can be used for irrigation, except at some sites, especially in the Raniganj Formation area,
where high salinity, sodium adsorption ratio, %Na, residual sodium carbonate, and excess Mg restrict its suitability for agricultural
uses. 相似文献
14.
15.
Viscous Potential Flow Analysis of Kelvin–Helmholtz Instability of a Cylindrical Flow with Heat and Mass Transfer 下载免费PDF全文
A linear analysis of Kelvin–Helmholtz instability of a cylindrical interface has been carried out when there is heat and mass transfer across the interface, using viscous potential flow theory. Both fluids are considered as incompressible, viscous, and thermally conducting with different kinematic viscosities. Both axisymmetric as well as asymmetric disturbances are considered. Stability criterion is given by a critical value of relative velocity and stability is discussed theoretically as well as numerically. Various graphs with respect to physical parameters such as wave number, viscosity ratio, heat transfer coefficients, Reynolds number, etc., have been drawn and the effect of various parameters have been described. A comparison with the linear stability analysis of inviscid fluids (Lee [10]) has been made and it is observed that viscosity has a stabilizing effect on the stability of the system. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res, 43(6): 489–503, 2014; Published online 3 October 2013 in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21092 相似文献
16.
Fabrication and Circuit Modeling of NMOS Inverter Based
on Quantum Dot Gate Field-Effect Transistors
Supriya Karmakar John A. Chandy Mukesh Gogna Faquir C. Jain 《Journal of Electronic Materials》2012,41(8):2184-2192
This paper presents the fabrication of a negative-channel metal–oxide–semiconductor (NMOS) inverter based on quantum dot gate field-effect transistors (QDG-FETs). A QDG-FET produces one intermediate state in its transfer characteristic. NMOS inverters based on a QDG-FET produce three states in their transfer characteristic. The generation of the third state in the inverter characteristic makes this a promising circuit element for multivalued logic implementation. A circuit simulation result based on the Berkley simulation (BSIM) circuit model of the QDG-FET is also presented in this paper, predicting the fabricated device characteristic. 相似文献
17.
18.
Prakash Parthasarathy Hang Seok Choi Hoon Chae Park Jae Gyu Hwang Ho Seong Yoo Byeong-Kyu Lee Mukesh Upadhyay 《Korean Journal of Chemical Engineering》2016,33(8):2268-2286
Waste tyres have become a grave concern as their accumulation is aggregating every year. Not only the size of waste tyre has to be reduced, but also some useful energy has to be recovered out of it as the world badly requires energy from alternate sources. Pyrolysis is one such method to extract energy potential products from waste tyres. It is extensively used to generate carbon black (solid product), tyre-oil (liquid product) and syngas (gas product) from waste tyres. In that connection, this article discusses the effect of various parameters on the product composition of pyrolysis of waste tyres. The current usage of pyrolysis products and their typical characteristics are also discussed in this critique. Of late, extraction of high value added products, such as activated carbon from carbon black, and limonene from tyre-oil is gaining attention. The article also throws some light on the application and generation routes of activated carbon and limonene from waste tyres. 相似文献
19.
To facilitate molecular spectroscopic observation of the mysterious transition of dissolved sodium silicate molecules into
nanoparticles of desired silica gel and zeolite structures, the IR and Raman spectra of Na2H2SiO4 monomers are studied here in details. It is demonstrated that the 3–0.2 mol/L aqueous solutions of Na2SiO3 and Na2SiO3 × 9H2O contain mostly Na2H2SiO4 monomers dissociated about 30%–80%, respectively. In contrast to the common belief the Si–O vibrations of these monomers
depend on their dissociation level generating FTIR and Raman bands which are frequently associated with polymer silica structures
in the current literature. To stay consistent with the molweight and dissociation measurements, these vibrational assignments
are revised in this paper. Some unique and unexpected effects of D2O used instead of H2O as solvent are also reported. 相似文献
20.
Summary The three-dimensional Poisson-Voronoi model, which is topologically equivalent to the microstructure of real ceramics and metals, has been used to study the stress distribution within a simulated polycrystalline aggregate having 200 grains. Micro-stresses such as the maximum principal stress, maximum shear stress, first invariant of stress, and Von-Mises stress are found to vary systematically with the anisotropy of single crystal. 相似文献