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Most developing countries such as India use biomass as a primary source of energy especially in domestic sectors in the rural area. The increasing population exerts more pressure on the biomass resource thereby initiating energy crisis in the region. The issue of shortage of fuelwood in the remote mountain regions is increasing since the alternative energy resources have limitations either due to poor economic condition of the people, complex technology involved or being inaccessible due to remoteness. It is also seen that the use of traditional biomass as a source of energy will improve the livelihood conditions of the people and it will give ecological benefits to the region if other associated factors like health, gender etc. are taken care of and thus the planners aim to focus on sustaining the natural fuelwood resources. The present paper attempts to predict the future fuelwood demand based on the present consumption pattern in the upland villages of Indian Himalaya. Major consumption characteristics such as fuelwood consumption at different altitude and per capita fuelwood consumption (PCFC) are studied. Population dynamics model is postulated in order to assess future population vs. fuelwood consumption scenario, thereby projecting the future population and the future fuelwood demand in the region.It is observed that variations in fuelwood consumption exist at different altitudes in the hilly region. Mathematical modelling and time-series simulation model was proposed and validated model to predict the future expected demand of fuelwood resources in Phakot watershed. Based on the projected population and season based fuelwood requirements, the watershed will have a total fuelwood demand of 19,327 t in 2011 which is expected to reach 36,462 t in 2021. Such studies on the future resource demand trends will help in finding suitable region-specific and need-based alternative strategies for achieving sustainable fuelwood management at the micro-level. 相似文献
64.
In this paper we have designed a Split-radix type FFT unit without using multipliers. All the complex multiplications required for this type of FFT are implemented using Distributed Arithmetic (DA) technique. A method is incorporated to overcome the result overflow problem introduced by DA method. Proposed FFT architecture is implemented in 180 nm CMOS technology at a supply voltage of 1.8 V. 相似文献
65.
We investigated the size dependent ferromagnetism in dodecyl amine capped zinc oxide nanoparticle. X-ray diffraction and X-ray photoelectron spectroscopy analysis demonstrated that density of oxygen vacancies was enhanced due to an increase in compressive strain concomitant with the decrease in particle size. Magnetic measurements showed increased ferromagnetic ordering in ZnO nanoparticles with reduced particle size. It was also found that the increase in coercive field, saturation magnetization and magnetic hysteresis loop area were invariably associated with increased oxygen defect population. The observed ferromagnetism in organic capped zinc oxide nanocrystals has therefore been assigned to defect induced phenomena. Results of sample characterization using optical absorption spectroscopy, photo luminescence spectroscopy and high resolution transmission electron microscope have also been presented. 相似文献
66.
Sunil Kedia Subrata Pradhan Biswanath Rath Kalpesh Doshi Yohan Khristi Dipak Patel Upendra Prasad Ashoo N. Sharma 《Journal of Superconductivity and Novel Magnetism》2013,26(4):1289-1296
Stable operation of superconducting magnets depend critically on the balance of heat deposition rate versus heat extraction rate by the cryo-coolant. Thus, the mass flow rate of the coolant in case of force-flow cooled superconducting magnet with Cable-In-Co-nduit-Conductor (CICC) construction becomes an important factor for optimum stability of magnets. The Toroidal and Poloidal Field magnets of Steady-state Superconducting Tokamak-1 (SST-1) is made of superconducting CICC with a void fraction of 40 %±2 %. For adequate cooling of magnets, supercritical helium at 4 bar and 4.5 K is forced-flown through the voids. Effect of temperature on mass flow rate and pressure drop in SST-1 CICC is studied in a 7 m long piece wound helically. The experimental friction factor of the CICC is also measured at different temperatures and flow rates and is compared with the standard Katheder equation and Tada equation. Also, based on the new findings obtained from the experimental results, the dimensionless Reynolds number has been slightly modified. This new number is used to propose a modified Katheder correlation for the friction factor in CICCs similar to that of SST-1. 相似文献
67.
Ambrish Kumar Srivastava Anoop Kumar Pandey Saurabh Pandey 《Polycyclic Aromatic Compounds》2016,36(4):452-466
In this article, we made a comparative study of two multiple myeloma drugs: lenalidomide and pomalidomide. We calculated and discussed their geometries at DFT/B3LYP method. Intra-molecular hydrogen bonding in these molecules is confirmed and characterized by QTAIM calculations. Electronic parameters along with HOMO-LUMO and MESP surfaces are calculated in order to compare their chemical reactivity. The effect of structure and bonding on electronic properties and biological activities is discussed and it is established that pomalidomide is more biologically active than lenalidomide. The phenyl ring of these molecules show teratogenic effects, making a possibility of finding another new class of drugs. 相似文献
68.
N. Sadasivan M. Balasubramanian R. Venkatesh S. Vigneshram T. Sunil 《Materialwissenschaft und Werkstofftechnik》2019,50(2):155-164
Severe plastic deformation improves the strength of a metal by strain hardening. Of the various severe plastic deformation processes, equal channel angular pressing proves to be the right candidate for bulk metal processing. Extensive works were carried out on equal channel angular pressing with channel angle ranging from 90° to 120 ° with or without back pressure on the exit channel. Numerical analyses suggest that reducing the channel angle below 90° would enhance the magnitude of strain imparted and, with prediction of a lesser strain homogeneity in such cases. Hence an acute angled equal channel angular pressing die with a back‐pressure notch sunken into the roof of the exit channel was designed, fabricated and was used for processing pure aluminium. Various mechanical properties of the processed materials were tested and acute angle processing imparted superior tensile strength to the work pieces in a single pass that would require several passes in a conventional equal channel angular pressing die. Substantial improvement in grain refinement and torsional properties was identified. 相似文献
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R. K. Tyagi K. K. Srivastava R. S. Pandey 《Surface Engineering and Applied Electrochemistry》2012,48(1):64-68
The material removal within different machining process can be performed in distinct modalities. One of the modality is based
on the effect of impact phenomenon. In this paper theoretical model of non-traditional machining process based on impact phenomenon
is discussed. The material is removed from the surface due to the impact of ions. The velocity of ions is equal to the velocity
at which the electrostatic ion-cyclotron instability driven by parallel flow velocity shear generated by massive ions takes
place. The main ways for the material removal as consequence of the impact phenomenon are the microcracking, microcutting,
melting and vaporizing of small quantities from the work-piece surface layer. 相似文献