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41.
Thermodynamic consistency of the interaction parameter formalism 总被引:1,自引:0,他引:1
The apparent contradiction between the exact nature of the interaction parameter formalism as presented by Lupis and Elliott
and the inconsistencies discussed recently by Pelton and Bale arise from the truncation of the Maclaurin series in the latter
treatment. The truncation removes the exactness of the expression for the logarithm of the activity coefficient of a solute
in a multi-component system. The integrals are therefore path dependent. Formulae for integration along paths of constant
Xi,or X
i/Xj are presented. The expression for In γsolvent given by Pelton and Bale is valid only in the limit that the mole fraction of solvent tends to one. The truncation also destroys
the general relations between interaction parameters derived by Lupis and Elliott. For each specific choice of parameters
special relationships are obtained between interaction parameters. 相似文献
42.
Lightweight ciphers are increasingly employed in cryptography because of the high demand for secure data transmission in wireless sensor network, embedded devices, and Internet of Things. The PRESENT algorithm as an ultra-lightweight block cipher provides better solution for secure hardware cryptography with low power consumption and minimum resource. This study generates the key using key rotation and substitution method, which contains key rotation, key switching, and binary-coded decimal-based key generation used in image encryption. The key rotation and substitution-based PRESENT architecture is proposed to increase security level for data stream and randomness in cipher through providing high resistance to attacks. Lookup table is used to design the key scheduling module, thus reducing the area of architecture. Field-programmable gate array (FPGA) performances are evaluated for the proposed and conventional methods. In Virtex 6 device, the proposed key rotation and substitution PRESENT architecture occupied 72 lookup tables, 65 flip flops, and 35 slices which are comparably less to the existing architecture. 相似文献
43.
Srikanth Thota Gurudath C. Srikantaiah Padmanabhan Basavaraj S. Akkimaradi Amrit Ambirajan Narasimham GSVL 《传热工程》2019,40(11):959-970
A pulse tube cryocooler (PTC) for future metrological satellites has been developed at one of the lead centers of the Indian Space Research Organisation in Bangalore, India for cooling on-board Infrared (IR) detectors to 80 K.A study has been conducted on the coldfinger of PTC to understand the off-state heat loads on the cooler by varying the value of gravity numerically in ANSYS FLUENT and experimentally by orienting the setup with respect to gravity. The off-state parasitic losses represent a major heat load in on-board applications that include redundant, viz. nonoperating coolers. To find out the amount of off-state parasitic heat losses in a nonoperating coldfinger of the PTC experimentally, transient warm-up technique was used. Various heat loads were applied experimentally on the cryo-tip at temperatures ranging from 80 to 100 K for determining the parasitic losses. The effect of orientation of PTC on the off-state parasitic heat load with respect to gravity is studied and presented in this paper. Enhancement due to free convection heat flow normalized by gas molecular conduction in pulse tube is analyzed using computational fluid dynamics to verify and compare with experimental results. The best orientation angle where the parasitic is low is when the cold end of the coldfinger of pulse tube cryocooler faces down (0°) and high when the cold end of the coldfinger is oriented to 135°. 相似文献
44.
This article presents a metaheuristic approach, the binary whale optimization algorithm (BWOA), to solve complex, constrained, non-convex, binary-nature profit-based unit commitment (PBUC) optimization problems of a price-taking generation company (GenCo) in the electricity market. To simulate the binary-nature PBUC problem, the continuous, real-value whale position/location is mapped into binary search space through various transfer functions. This article introduces three variants of BWOA using tangential hyperbolic, inverse tangent (arctan) and sigmoidal transfer functions. The effectiveness of the BWOA approaches is examined in test systems with different market mechanisms, i.e. an energy-only market, and energy and reserve market participation with different reserve payment methods. The simulation results are presented, discussed and compared with other existing approaches. The convergence characteristics, solution quality and consistency of the results across different BWOA variants are discussed. The superiority and statistical significance of the proposed approaches with respect to existing approaches is also presented. 相似文献
45.
Raj Kumar Chetan M. Patel Arun K. Jana Srikanth R. Gopireddy 《Advanced Powder Technology》2018,29(11):2822-2834
An Artificial Neural Network (ANN) was developed to predict the mass discharge rate from conical hoppers. By employing Discrete Element Method (DEM), numerically simulated flow rate data from different internal angles (20°–80°) hoppers were used to train the model. Multi-component particle systems (binary and ternary) were simulated and mass discharge rate was estimated by varying different parameters such as hopper internal angle, bulk density, mean diameter, coefficient of friction (particle-particle and particle-wall) and coefficient of restitution (particle-particle and particle-wall). The training of ANN was accomplished by feed forward back propagation algorithm. For validation of ANN model, the authors carried out 22 experimental tests on different mixtures (having different mean diameter) of spherical glass beads from different angle conical hoppers (60° and 80°). It was found that mass discharge rate predicted by the developed neural network model is in a good agreement with the experimental discharge rate. Percentage error predicted by ANN model was less than ±13%. Furthermore, the developed ANN model was also compared with existing correlations and showed a good agreement. 相似文献
46.
47.
Hapipi Nurhidayah Mohd Chen Soo Kien Shaari Abdul Halim Kechik Mohd Mustafa Awang Lim Kean Pah Tan Kar Ban Lee Oon Jew Arvapalli Sai Srikanth Miryala Muralidhar 《Journal of Materials Science: Materials in Electronics》2022,33(14):11269-11270
Journal of Materials Science: Materials in Electronics - 相似文献
48.
Multimedia Tools and Applications - Nowadays, the contour models (CMs) are widely used in image segmentation. Among these CMs, the Chan and Vese model depending on level set is the current regional... 相似文献
49.
ABSTRACTIn this paper, we prepare silver nanowires circuit graphics by UV-curing technology. The optimal condition of preparation of the silver nanowires circuit graphics are examined. Experiment results show that the UV-curing technology is a kind of individual, low-cost and environment-friendly method to prepare silver nanowires circuit graphics. The main influence factors on the lines' width are the UV beam power and scanning speed. And we also study the influence of the hot pressing temperature on the resistivity of the circuit graphics. In the experiments, the optimal condition is that the UV beam power is 190 mW and the scanning rate is 6 cm/s, then we get the minimum line width, which is 0.25 mm. The thickness of silver nanowires layer is 100 µm and the hot pressing temperature is 100°C, we will get the sample whose resistivity is 21× 10?5 Ω·cm. 相似文献
50.
Srikanth Jagadeesan Yang Hoi Doh Kyung-Hyun Choi 《Journal of Coatings Technology and Research》2017,14(3):701-708
Titanium dioxide (TiO2) thin film was fabricated using titanium isopropoxide as a precursor through an atmospheric low-temperature roll-to-roll chemical vapor deposition method. TiO2 was deposited on the PET substrate in the temperature range of room temperature to 100°C, and the working pressure was 740 Torr. The surface morphology of TiO2 thin film was analyzed by field emission scanning electron microscopy and a 2D surface profiler. The results revealed that the growth rate of TiO2 film was 31 nm/min at 100°C, and it also showed that the surface is uniform and smooth. Moreover, the lowest root mean square roughness (R q) value of 1.87 nm was obtained for TiO2 film prepared at 100°C. The composition of TiO2 film was confirmed by X-ray photoelectron spectroscopy (XPS) analysis. The film showed very good chemical and optical properties while increasing the substrate deposition temperature. The UV–Vis spectroscopy analysis revealed that TiO2 films exhibited excellent optical transmittance, more than 91% observed in the visible region. 相似文献