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排序方式: 共有564条查询结果,搜索用时 15 毫秒
41.
Using the basic equations of heat conducting micropolar fluid, heat transfer through a channel of porous walls has been studied. The temperature distribution is obtained for different values of suction parameter , convective parameter and micropolar parameter . 相似文献
42.
In this paper a performance based comparison of top and bottom contact organic thin film transistor (OTFT) device structures, using two dimensional numerical simulations has been carried out. In addition to this, investigations pertaining to the estimation of contact resistance in these OTFTs were also performed. To estimate contact resistance the conventional transmission line method and modified transmission line method (M-TLM) were respectively invoked. Our simulation results clearly indicate that the latter is more accurate in the estimation of contact resistance compared to the conventional method. Furthermore, the M-TLM was used to estimate the gate voltage and film thickness dependence of the contact resistance for the two device structures. The observed results have been explained on the basis of the significantly lowered area of carrier injection and extraction regions, at the source/channel and channel/drain interface respectively, in bottom contact transistor that lead to its inferior performance over the top contact transistor. 相似文献
43.
44.
J. Moteff R. K. Bhargava W. L. McCullough 《Metallurgical and Materials Transactions A》1975,6(5):1101-1104
It is shown that the ultimate tensile strength, σ, of 304 stainless steel can be correlated with hot-hardness measurements
at temperatures up to 1200°C using the expression σ = (H/3.0)(n/0.2n)
n
whereH is the diamond pyramid hardness number andn is the strain hardening coefficient. The strain hardening coefficient was obtained from a Meyer’s hardness coefficient at
the room temperature test condition and for test temperatures up to about 0.5T
m
, from the empirical relationshipn =k/λ. Herek is a constant equal to approximately 0.2 microns and λ is the subgrain dimension of the deformed specimen as obtained by
transmission electron microscopy.
Formerly with General Electric Company, Cincinnati, Ohio 相似文献
45.
Sarma Rajkumar Bhargava Cherry Jain Shruti Kamboj Vikram Kumar 《Neural computing & applications》2021,33(14):8893-8922
Neural Computing and Applications - Recently established Harris Hawks optimization (HHO) has natural behaviour for finding an optimum solution in global search space without getting trapped in... 相似文献
46.
The problem of transporting constant-bit-rate (CBR) traffic through a packet network is analyzed. In the system considered, CBR traffic is packetized and packets from several similar sources are multiplexed on a transmission link. The bit streams are recreated at the receiving end by demultiplexing the packets and then playing out the packets of each CBR stream. Traffic fluctuations may cause gaps to appear in the playout process. Their frequency can be reduced by adding a smoothing delay to each stream. The queueing system analyzed has periodic arrivals and deterministic service times. A method of analysis, based on the ballot theorems of Takacs (1967), is presented to provide steady-state delay distributions as well as a transient analysis of the system to predict the statistics of the time for a gap to develop in the CBR stream as a function of the smoothing delay 相似文献
47.
A simplified generalized finite difference solution using MATLAB has been developed for steady‐state heat transfer in a bar, slab, cylinder, and sphere. Solutions are given for all types of boundary conditions: temperature and flux boundary conditions. A generalized solution for 2D heat transfer in a slab is also developed. Solutions have been compared with analytical solutions and there is very good agreement between computed and analytical solutions. The solution can easily be extended to similar types of situations in fluid flow and mass transport operations. 相似文献
48.
M.J.P. Naik J. Debbarma M. Saha A. Bhargava 《Materialwissenschaft und Werkstofftechnik》2020,51(3):368-374
Nowadays, the synthesis of graphene/ graphene oxide from graphite precursor using oxidizing agents is the most common procedure, but the direct synthesis of graphene or graphene oxide from a non-graphitic carbonaceous material without using inert atmosphere is really a great challenge. Besides, the chemistry behind the development of graphitic structure from a non-graphitic material during the thermal heating is still not clearly understood. In this research work, three agrowaste materials viz. rice husk, sugarcane bagasse and newspaper were selected and subjected to pyrolysis in presence of trace amount of air. The continued heating at the optimum temperature has resulted in aromatization and condensation along with the oxidation within the cellulosic structure of the agrowaste, which finally resulted in the formation of graphene oxide nanoflakes directly. The mechanism of formation of graphene oxide from these agrowaste materials was studied, which suggested that any carbonaceous waste materials can be converted to graphene oxide by optimizing the thermal heating conditions. 相似文献
49.
Using the micropolar theory, a set of boundary layer equations are obtained for the two dimensional flow of an incompressible micropolar fluid near a stagnation point. The boundary conditions of isothermal and insulated wall are taken with VISCOUS DISSIPATION effects. Numerical results for the temperature distribution has been shown graphically for different values of the material parameters and Prandtl number. 相似文献
50.
Breast Cancer Therapy: Defined Host–Guest Chemistry on Nanocarbon for Sustained Inhibition of Cancer (Small 42/2016) 下载免费PDF全文