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991.
Álvaro Enríquez-de-Salamanca 《影响评估与项目评价》2013,31(2):152-159
AbstractThis paper discusses project splitting in environmental impact assessment (EIA), investigating the current state of knowledge through literature, legislation, case-law and practice, discussing problems and providing solutions. The focus is on Spain, but many of the conclusions are applicable worldwide. Project splitting is a much more common practice than generally accepted. The main efforts have been focused on preventing salami-slicing as a mechanism to avoid the EIA, but it is a much more complex problem, with different ways of splitting and reasons for doing so. Measures to avoid this practice should include strengthening the strategic environmental assessment, a greater involvement of the approval authority, specific prohibitions in regulations, using case-by-case examinations instead of thresholds, compulsory scoping and avoid the exclusion of project parts during the EIA. 相似文献
992.
A kinematics model of the upper limb was developed using three degrees of freedom on the shoulder and one on the elbow. Whilst the direct kinematics equation computes the position of the hand, the inverse kinematics equation provides the upper limb's joint angles related to a given posture. Only after defining a discomfort cost function that accounts for the joint's displacement from the neutral position, the inverse kinematics equation for this model proved analytically solvable. Such solution was used in conjunction with observational postural assessment methods in order to improve the subjective estimation of the joint angles. Besides that, it was shown the utility of the direct kinematics equation in the rearrangement of the elements of the workplace. 相似文献
993.
José Antonio Sánchez-Martín Alejandro Escuer Sebastián Jarabo José Miguel Álvarez 《Journal of Modern Optics》2013,60(17):2865-2874
A simple theoretical model for erbium-doped fibre ring lasers is presented. This model is experimentally verified by means of the comparison between theoretical values and measurements of efficiency, threshold pump power and output laser power employing a wide set of experimental situations. This model provides semi-analytical equations, which characterise the erbium-doped fibre, determining its absorption and emission spectral coefficients. 相似文献
994.
F. lvarez N. Moraga J. Cousteix 《International journal for numerical methods in engineering》2006,66(2):191-213
The quasi‐simultaneous interactive boundary layer (IBL) method is improved with the iterative correction of an inviscid operator. The updated interactive boundary layer method (UIBL) presented in this work, uses the Hess–Smith panel method (HSPM) as an inviscid operator to update the outer flow calculation and the inviscid velocity in the interaction law (IL). The discretization of the Hilbert integral (HI) from the original method is modified to reduce the error introduced by the calculation of the HI in a restricted domain. The method is tested on a flat plate with a small indentation for two‐dimensional, steady, incompressible and laminar flow. The UIBL method is capable to predict the flow separation and reattachment with good accuracy. The accuracy of the results is competitive with the numerical solution of the Navier–Stokes equations (NSE). Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
995.
E. Cervantes-González M. L. Castillo-López C. J. Guzmán-Álvarez F. M. Díaz-de-León J. M. Ortega-Arce 《Petroleum Science and Technology》2013,31(8):872-879
A microcosm scale experiment was set up to evaluate the effect of the addition of chicken feathers 5% (w/w) on the biodegradation of diesel (27,000 ppm) and kerosene (24,000 ppm) in soil using a mixed bacterial culture with hydrocarbonoclastic and keratinolytic capacities. During six weeks, the authors monitored nitrogen content, phosphorus, pH, moisture, soluble protein, protease and lipase activity, and residual hydrocarbons content. The results showed that the addition of feathers had the best efficiency on the biodegradation of diesel (20,800 ppm) and kerosene (13,480 ppm) and, additionally, the feathers were simultaneously degraded. 相似文献
996.
When a wind turbine works in yaw, the wake intensity and the power production of the turbine become slightly smaller and a deflection of the wake is induced. Therefore, a good understanding of this effect would allow an active control of the yaw angle of upstream turbines to steer the wake away from downstream machines, reducing its effect on them. In wind farms where interaction between turbines is significant, it is of interest to maximize the power output from the wind farm as a whole and to reduce fatigue loads on downstream turbines due to the increase of turbulence intensity in wakes. A large eddy simulation model with particular wind boundary conditions has been used recently to simulate and characterize the turbulence generated by the presence of a wind turbine and its evolution downstream the machine. The simplified turbine is placed within an environment in which relevant flow properties like wind speed profile, turbulence intensity and the anisotropy of turbulence are found to be similar to the ones of the neutral atmosphere. In this work, the model is used to characterize the wake deflection for a range of yaw angles and thrust coefficients of the turbine. The results are compared with experimental data obtained by other authors with a particle image velocimetry technique from wind tunnel experiments. Also, a comparison with simple analytical correlations is carried out. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
997.
998.
999.
Biomechanical and biological properties of the implant material carbon-carbon composite covered with pyrolytic carbon 总被引：6，自引：0，他引：6
Pesáková V Klézl Z Balík K Adam M 《Journal of materials science. Materials in medicine》2000,11(12):793-798
The aim of this study was to test C/C material (carbonized, graphitized or covered with pyrolytic carbon) designated for the use in orthopaedic and bone surgery. Using an in vitro assay we confirmed, that the cell proliferation was exhibited the mostly on the C/C composite coated with pyrolitic carbon and afterwards polished. The two latest of subsequent water extracts of this material had a slightly inhibiting effect on the cells metabolic activity. Biocompatibility test in vivo performed subcutaneously on rats did not show big differences between three tested implants (C/C composite, epoxy resine, titanium alloy), on the other hand the plates tested on pigs demonstrated foreign-body reaction induced by wear C/C composite material. Such debris were found both in the neighborhood of the implant as well as in the lymphatic node. 相似文献
1000.