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81.
Soon Young Min Sanjeev Maken Jin-Won Park Ankur Gaur Jang Soo Hyun 《Korean Journal of Chemical Engineering》2008,25(2):323-328
In this study, we melted four types of waste asbestos containing material such as spread asbestos, plasterboard asbestos,
slate asbestos and asbestos 99 wt%, in a melting furnace at 1,450–1,550 that uses a mixture of hydrogen and oxygen (Brown’s
gas) as a fuel. More volatile components (CaO, K2O) are enriched in spread asbestos, plasterboard asbestos, and slate asbestos, while less volatile compounds (SiO2, Fe2O3, MgO) remain in asbestos 99%. Through basicity of raw materials, spread asbestos, plasterboard asbestos, and slate asbestos
were found to have more alkalinity, and asbestos 99% was found more acidic. SEM and EDX results revealed that all raw materials
had various kinds of asbestos fiber. Spread asbestos, plasterboard asbestos, and slate asbestos were considered as tremolite
asbestos, whereas asbestos 99% was considered as chrysotile asbestos. It was further confirmed by SEM and XRD studies that
all waste materials contained some crystalline structures which transformed into amorphous glassy structure on melting. Also,
in case of added glass cullet during the melting of spread asbestos, it transformed the raw material into a perfect vitrified
product having more glassy surface and amorphous in nature 相似文献
82.
Deng Jing Han Yunghsiang S. Kulkarni Sanjeev R. 《Wireless Communications, IEEE Transactions on》2009,8(4):1591-1596
We analyze the delay performance of RTS/CTS-based (Request-To-Send/Clear-To-Send) multi-channel MAC (Medium Access Control) schemes for wireless networks. These schemes usually employ multiple data subchannels for data transmission and one control subchannel to send the RTS/CTS dialogue for channel reservation. Through theoretical analysis and simulations, we show that, in fully-connected networks, such multi-channel MAC schemes suffer longer delays than the corresponding single channel MAC scheme, that puts the RTS/CTS dialogue on the same channel as data packet transmissions. This conclusion holds even when data packets have different priorities and higher priority traffic is sent ahead of lower priority traffic. 相似文献
83.
Sanjeev Kumar Manjhi 《Numerical Heat Transfer, Part A: Applications》2019,75(3):200-216
The measurement of surface heating rate is an imperative parameter in the force convection ground-based facility for short duration investigation due to the heat transfer rate is changing rapidly. The coaxial thermocouples are suitable to measure the transient heat flux in fast varying heat transfer application because of having fast response time in the range microseconds or less. In this addition, the K-type, E-type, and J-type of coaxial thermocouples are contrived as well as the thermal coefficient resistance (TCR) and sensitivity (S) has been calculated from oil-bath based technique. These handmade coaxial thermocouples are exposed in a forced convection flow facility having three different input step heat loads as well as their transient heat fluxes are estimated using one-dimensional heat conduction modeling for the semi-infinite body. The numerical simulation has also been carried out with the analogous experimental parameters using ANSYS-FLUENT v.15.0 and compared with the outcome of the experimental approach and it is found that the average value of the transient temperatures having 0.3% error and surface heat flux recovered from this temperature is 10%. This study reveals the measuring ability of these handmade coaxial thermocouples at low temperature and low velocity on short duration transient measurements. 相似文献
84.
Silicon - Negative Bias Temperature Instability (NBTI) is a key reliability and consistency issue for ultra-scaled Silicon IC technology with substantial consequences on both analog and digital... 相似文献
85.
Radha V. Doddamani Padmeshwary S. Rachipudi Sanjeev R. Inamdar Mahadevappa Y. Kariduraganavar 《Polymer Engineering and Science》2019,59(3):500-509
This article describes the synthesis of substituted triazolo[3,4‐b]‐thiadiazole heterocycles based nonlinear optical (NLO) responsive chromophores. To enhance the NLO properties of the chromophores, the pyrimidine ring was introduced with an appropriate π‐bonding. With these chromophores, different series of polyurethanes were prepared by condensation with tolylene‐2,4‐diisocyanate and 3,3′‐dimethoxy‐4,4′‐biphenylene diisocyanate. The structure of the resulting chromophores and polyurethanes was confirmed using Fourier transform infrared, proton nuclear magnetic resonance, and Carbon Hydrogen Nitrogen (CHN) analyzer. The inherent viscosities (ηinh) of the polyurethanes measured by Ubbelohde viscometer were in the range of 0.2324–0.2760 dl/g. Thermal behavior of the polyurethanes was investigated using differential scanning calorimetry and thermogravimetric analysis. The molecular orientation in polyurethane films was induced by a corona poling, and this was ascertained using ultraviolet‐visible spectrophotometer and atomic force microscope. The thicknesses and refractive indices of thin films were determined by an Ellipsometer. Polyurethanes exhibited excellent solubility in most of the common organic solvents. The second harmonic generation (SHG) coefficients (d33) of the poled polyurethanes ranged from 63.20 and 95.32 pm/V at 532 nm. None of the polyurethanes showed SHG decay below 100°C, and retained 95% of the signal even up to 500 h. The resulting enhanced NLO efficiency and longer temporal stability make these polyurethanes as promising candidates for photonic devices. POLYM. ENG. SCI., 59:500–509, 2019. © 2018 Society of Plastics Engineers 相似文献
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88.
Wireless Personal Communications - Next-generation internet of things (IoT) applications need numerous low-powered wireless mobile devices to connect with each other, having ultra-reliability and... 相似文献
89.
Recently, a dynamic adaptive queue management with random dropping (AQMRD) scheme has been developed to capture the time-dependent variation of average queue size by incorporating the rate of change of average queue size as a parameter. A major issue with AQMRD is the choice of parameters. In this paper, a novel online stochastic approximation based optimization scheme is proposed to dynamically tune the parameters of AQMRD and which is also applicable for other active queue management (AQM) algorithms. Our optimization scheme significantly improves the throughput, average queue size, and loss-rate in relation to other AQM schemes. 相似文献
90.
Akshita Abrol Rakesh Kumar Jha Sanjeev Jain Preetam Kumar 《Telecommunication Systems》2018,68(2):201-215
Green communication has emerged as the most important concept for the next generation networks. Along with improved data rate and capacity, the upcoming 5G networks aim at improving energy efficiency without compromising on the user experience. In this paper, we have used amplify and forward relays in the heterogeneous network topology consisting of low power and high power nodes. A three layered system model for power optimization is discussed using a relay selection strategy for power optimization with the aim to improve energy efficiency of the network. Further, we have used Hidden Markov Model for training and maintaining of base station, relay and SCA with the aim of probabilistic power allocation to client nodes in order to solve the power optimization problem. We have also used adaptive modulation schemes for lowering the power consumption of the network to meet our goal of green communication for the next generation network. 相似文献