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11.
12.
An analytical study is presented on the modal dispersion characteristics, group velocity, and effective group, as well as the phase index of a ternary one dimensional plasma photonic crystal for an obliquely incident electromagnetic wave considering the effect of collisions in plasma layers. The dispersion relation is derived by using the transfer matrix method and the boundary conditions based on electromagnetic theory. The dispersion curves are plotted for both the normal photonic band gap structure and the absorption photonic band gap structure. It is found that the increase in the angle of incidence shifts the photonic band gap toward higher frequencies. Also, the cutoff frequency is independent of collisions. 相似文献
13.
P. S. ROY B. K. RANGANATH P. G. DIWAKAR T. P. S. VOHRA S. K. BHAN I. J. SINGH 《International journal of remote sensing》2013,34(11):2205-2225
Abstract The Andaman Nicobar group of islands in the Andaman Sea are blessed with luxuriant tropical vegetation. During recent years, vegetation in these islands has been under tremendous pressure due to increased settlement and commercial extraction, Landsat TM data of the Baratang forest division of the Andaman group of islands has been used to prepare forest type maps using visual and digital methods. Digital enhancement techniques have been evaluated to discriminate forest types in a typical environmental set-up. The mapping techniques have been compared with respect to classification and accuracy levels. Finally, the land transformation in the forest division has been studied using past aerial photographs. The study highlights the appropriate methodology required to map forest types. 相似文献
14.
Research on information communication technologies (ICT) for entrepreneurship development is burgeoning, yet our understanding of the use of ICT in support of grassroots innovation remains unclear. This paper examines the moderating role of the use of ICT on the relationship between grassroots innovation (GRI) and entrepreneurial success (ES). The study involved 400 grassroots entrepreneurs selected from three states in India, and the moderating effect of the use of ICT was analysed using moderated structural equation modelling. The results revealed that the use of ICT partially moderates the relationship between the new learning practices and economic benefits. It also partially moderates the relationship between local solution and economic benefits, but it fully moderates the relationship between networking capabilities and economic benefits, where the relationship is stronger when the use of ICT is high. Furthermore, the study found that the use of ICT does not moderate the relationship between new learning practice and non-economic benefits, relationship between local solution and non-economic benefits and relationship between networking capabilities and non-economic benefits. 相似文献
15.
Extended octagonal rings are used in metal cutting dynamometers to measure cutting forces and torque. The controllable design variables are the thickness, radius and width of the ring. Normally the objectives of the design are to achieve high sensitivity and high rigidity which arc conflicting in nature. Therefore, both requirements cannot be achieved simultaneously. The goal programming technique is used to determine the optimum size of extended octagonal ring for various goal priorities with respect to sensitivity and rigidity 相似文献
16.
New algorithms are presented for power-system complex node voltage estimation, based on statistical linearization of power-flow equations and a least-squares criterion. To illustrate the algorithms a 7-bus power network is simulated on a computer and a comparison is made with estimates obtained through the conventional Taylor series approach. 相似文献
17.
Skin burns is one of the most common complications reported during treatment of early-stage breast cancer with radiofrequency ablation (RFA) technique. In this regard, the present study aims to analyze the efficacy of forced convection surface cooling in minimizing the skin burns during RFA of breast tumor. The study considers a heterogeneous three-dimensional numerical model of breast that has been constructed based on the anatomical details available in the literature. A spherical tumor of 1.5 cm has been embedded in the numerical model of breast to represent in-situ tumor in its early stage. A programmable temperature-controlled RFA has been performed by incorporating the closed-loop feedback PID controller into the numerical model. The thermo-electric analysis has been performed using a finite element based commercial solver COMSOL Multiphysics® to obtain the temperature distribution by incorporating the coupled electric field distribution, Pennes bioheat equation and Arrhenius rate equation. The temperature dependent electrical and thermal conductivities of both the tissue and tumor along with damage dependent perfusion rate have been incorporated to achieve better correlation with the clinical RFA. The numerical simulation results revealed that, there is a significant reduction in the temperature at outer periphery of breast with increase in convective heat transfer coefficient. Further, the effects of variation in surface cooling on temperature distribution, input voltage requirement and treatment time required for complete tumor necrosis have been studied. The simultaneous application of forced convective surface cooling along with RFA could play a vital role in addressing the most common complication of skin burns during treatment of breast cancer. 相似文献
18.
The principle of maximum entropy (POME) was employed to derive a new method of parameter estimation for the 2-parameter log-logistic distribution (LLD2). Monte Carlo simulated data were used to evaluate this method and compare it with the methods of moments (MOM), probability weighted moments (PWM), and maximum likelihood estimation (MLE). Simulation results showed that POME's performance was superior in predicting quantiles of large recurrence intervals when population coefficient of variation was greater than or equal to 1.0. In all other cases, POME's performance was comparable to other methods. In terms of parameter bias and root mean square error, POME was comparable to MLE and superior to both MOM and PWM. 相似文献
19.
Extended milling of rice decreased the incidence of mycoflora and reduced black tip discoloration but reduced the head rice yield and kernel weight. Protein content, ash, reducing sugars, nonreducing sugars and free fatty acids increased whereas amylose decreased significantly with the increase in the number of discolored grains. Discolored rice required significantly less time to cook, showed decreased water uptake, reduced kernel elongation and losses. Cooking time decreased; water uptake, elongation in cooked rice and gruel solid loss increased with an increase in the degree of milling. Correlation coefficients between the different variables were calculated. 相似文献
20.
DANA R. YOERGER ALBERT M. BRADLEY BARRIE B. WALDEN HANUMANT SINGH RALF BACHMAYER 《International journal of systems science》2013,44(10):1031-1044
This paper summarizes results from the first science deployment of the Autonomous Benthic Explorer (ABE), conducted on the Juan de Fuca Ridge (46°N, 129°W) at depths between 2200 and 2400 m. Using long baseline acoustic transponders, the ABE descended with precision to a preassigned starting point, then executed dead-reckoned tracklines. It followed the bottom at distances between 7 and 20 m using an acoustic fathometer as a reference sensor. The ABE mapped a new subsea lava flow with a magnetometer, imaged the seafloor with a stereo snapshot video system, and mapped a hydro thermal plume with conductivity and temperature sensors. The ABE completed 7 successful dives and covered over 35 km of tracklines. Detailed power records were logged, which permits extrapolation of the ABE's performance to other missions and higher capacity batteries. 相似文献