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81.
Quantitative data are presented for energy inputs and outputs for selected crops in India using either bullock-operated or tractor-operated farms. It is shown that large ratios are obtained for the energ outputs divided by the energy inputs. Preferred allocation of energy resources to the agricultural sector i recommended. 相似文献
82.
83.
This paper briefly describes various technical issues involved in the design and development of an object-based interoperability framework in support of Engineering Information Systems (EIS). It also discusses the interaction of such frameworks with various emerging standards and the possibility of developing standards in the area of object-oriented interoperable frameworks. Finally, it summarizes the background and the status of the project. 相似文献
84.
Burkholder R.J. Pathak P.H. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1991,79(10):1401-1412
Gaussian beam (GB) representation methods are used to analyze the electromagnetic coupling into and the scattering by a large nonuniform cavity. The aperture field in the cavity is decomposed into beams using the Gabor expansion, and shooting techniques are then employed. The method is illustrated only for the two-dimensional (2-D) case. The GBs are tracked axially using the rules of beam optics which ignore any beam distortion upon reflection at the walls. The effects of beam distortion are not significant for relatively slowly varying waveguide cavities. The field scattered into the exterior by the termination within the cavity is found using a reciprocity integral formulation which requires a knowledge of the beam fields near the termination. Numerical results based on this GB approach are presented and compared with results based on an independent reference solution 相似文献
85.
The increasing emphasis on mechanized farming, sophisticated post-harvest technology, and extensive processing of agricultural produce has led to progressively diminishing energy returns on the energy inputs in the agriculture sector. This paper evaluates the energy inputs and outputs in these various operations and examines the effect of the evolving technology on the energy returns from these operations. 相似文献
86.
Summary Liver fats ofCarcharias limbatus andPristis cuspidatus from the West Coast of India have been studied.
Lithium salt-acetone and lead salt-alcohol methods were adopted for the resolution of the fatty acids. An efficient, electrically
heated and packed column has been employed for fractionation of the methyl esters of fatty acids.
These fats have been found to have a high content of saturated fatty acids and thus belong to the fourth group of Tsujimoto's
classification of Elasmobranch fish liver fats.
Analyses of the liver oils from the same species of fish show that there is a tendeney towards saturation or hydrogenation
of polyethylenic acids accompanied by an increasing concentration of unsaponifiable matter, which is mainly alcohol ethers
of the selachyl type, in accordance with Lovern's views. 相似文献
87.
In contrast with cross-sectional designs used in previous studies, this exploratory study compared survey data from 127 matched pairs of clinical pharmacists and physicians working together. Physicians' perceptions of the importance of clinical pharmacy activities for patient care and the competence of pharmacists performing the activities were examined for their influence on prescribing behavior in an institutional setting. Data from a national survey showed that physicians rated pharmacists higher regarding recommendations based on drug use evaluations (p = 0.004) and competency to provide all clinical pharmacy services. Scores for pharmacokinetics ratings were similar between pharmacists and physicians (p = 0.168). Pharmacists rated the importance of recommendations based on cost-effectiveness higher than physicians (p = 0.012). Overall, physicians' perceptions of activity importance for patient care and pharmacist competency appear to dictate pharmacists' influence on physician prescribing behavior (R = 0.723). 相似文献
88.
Pathak R.N. Goossen K.W. Cunningham J.E. Jan W.Y. 《Photonics Technology Letters, IEEE》1994,6(12):1439-1441
We report growth of In0.53Ga0.47 As-InP multiple quantum well (MQW) modulators operating at 1.55 μm for fiber-to-the-home applications. By employing a 200-period InGaAs-InP MQW stack in the intrinsic region of a p-i-n structure and working in reflection, we have been able to realize surface-normal modulator devices that exhibit better than an 8:1 contrast ratio. This is the highest contrast ratio reported to date for this type of device working at this wavelength 相似文献
89.
Piyush Pathak Qiliang Yan Thomas Schmoeller Ebo Croffie Artak Isoyan Lawrence S. Melvin III 《Microelectronic Engineering》2009,86(4-6):500-504
Extreme ultraviolet lithography (EUVL) is a leading candidate for the 22 nm node lithography and beyond. However, there are still some critical problems before EUVL may be deployed in high-volume manufacturing. One of the critical problems is to estimate the EUVL aerial image formation for optical proximity correction (OPC) in order to compensate for EUVL effects such as shadowing and flare. This study discusses aerial image formation through modeling of optical transfer function to assimilate optical diffraction, long range layout dependent flare effects, and shadowing effects due to non-telecentric imaging optics in the EUV case. Hence, after optimizing optical process parameters to model the EUV aerial image, this study will investigate OPC modeling methods employed to compensate these optical effects in the mask design flow. 相似文献
90.
A highly convenient and efficient one step procedure for the synthesis of polystyrene thiol resin from Merrifield resin is described. Potassium O,O-diethyl thionophosphate is used as a thiolating reagent for the conversion of halogen (chloro) group to thiol functionality in refluxing DMF. By a simple procedure chloro methylated cross-linked polystyrene was thiolated through a nucleophilic substitution reaction. The modified beads were characterized by IR, laser Raman spectroscopy and elemental analysis. Evaluations of the functionalized beads were done by their halide scavenging and chelating efficiency. The novel feature of this method is simple and safe reaction, shorter reaction time and efficient loading of thiol functionality. 相似文献