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Agnieszka Generowicz Zygmunt Kowalski Joanna Kulczycka Agnieszka Makara 《洁净——土壤、空气、水》2011,39(7):688-696
The proposal of application of multi‐criteria analysis and technological quality method for optimization of technological processes on the case study of sodium chromate production variants from waste was presented. The research on the use of chromic waste for the production of sodium chromate made it possible to determine the optimal process parameters. Technological quality method was used to define the value of criterions for multi‐criteria analysis while multi‐criteria analysis allowed determining the impact of criterions weights for ranking variants of technological process. Both methods in a complex way evaluate the degree of modernization of technologies, describing them qualitatively within the area of environmental, technical, and the economic effects of the proposed technological variants. Based on the proposed evaluating criteria both methods yield comparable results. The most advantageous alternatives provided realization of the sodium chromate production process with the use of in‐process recycling of chromic mud, off‐site recycling of chromic tannery waste and on‐site recycling of waste from the old chromic heaps. 相似文献
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Rajmund DYBCZYNASKI Halina POLKOWSKA-MOTRENKO Zbigniew SAMCZYNASKI Zygmunt SZOPA 《Geostandards and Geoanalytical Research》1991,15(2):163-185
World-wide intercomparison runs has made possible the certification of two new Polish geological-environmental reference materials for multi-element trace analysis: Apatite Concentrate (CTA-AC-1) and Fine Fly Ash (CTA-FFA-1). "Recommended values' are established for 25 (CTA-AC-1) and 40 (CTA-FFA-1) elements respectively. In addition, "information values' are assigned for 12 elements in CTA-AC-1 and 10 elements in CTA-FFA-1. Our method of data evaluation has been further improved and a modified version of criteria for assigning recommended and information values is proposed. 相似文献
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Marcin Słowik Tadeusz Sobczyński Zygmunt Młynarczyk 《Environmental Earth Sciences》2010,59(5):957-966
Research concerning chemical constitution of alluvial sediments was done in the lower course of the Obra river (Western Poland).
The fragment of vertical profile, which consisted of various alluvial sediments (fine sands, peats, and sandy silts) was chosen
for detailed analysis. The main research problem was to determine if lithology and chemical constitution of alluvial deposits
are interconnected in a distinct way within studied section of the Obra river valley, and, if changes of chemical elements’
concentration could be used to illustrate depositional processes, which take place in riverbed and floodplain. Concentrations
of Fe, Mn, Cu, Zn, Ca, Mg, and K were determined in collected sediment samples. Next, geochemical groups of alluvial sediments
were distinguished using cluster analysis. Investigated changes of chemical elements’ concentration show that there is a distinct
border between the environment of organic sediments, which marks the place of former functioning of the Obra riverbed, and
sandy silts, which were deposited within floodplain during floods. Besides, floodplain sediments, riverbed sediments, and
reductive environment within peat deposits were singled out on the basis of the analysis. 相似文献
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Zygmunt Meyer 《Acta Geophysica》2011,59(2):317-333
The wind set-up of water level in a river is of great importance in many practical cases, notably in the river mouth section
where the slope of the free water table is very small (sometimes 10−5) and the wind shear stress acting at the water surface generates significant changes in the vertical velocity profile. If
the wind is blowing opposite to the main flow, an increase of water depth is observed. In the outlet area, the increase of
water depth can reach up to 0.5 m (Lower Odra River). The paper presents an analysis of wind set-up of water level based on
hydrodynamic principles. 相似文献
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A numerical study which takes into account wave dispersion effects has been carried out in the Indian Ocean to reproduce the initial stage of wave propagation of the tsunami event that occurred on December 26, 2004. Three different numerical models have been used: the nonlinear shallow water (nondispersive), the nonlinear Boussinesq, and the full Navier-Stokes aided by the volume of fluid method to track the free surface. Numerical model results are compared against each other. General features of the wave propagation agreed very well in all numerical studies. However some important differences are observed in the wave patterns, i.e., the development in time of the wave front is shown to be strongly connected to the dispersion effects. Discussions and conclusions are made about the spatial and temporal distribution of the free surface reaffirming that the dispersion mechanism is important for tsunami hazard mitigation. 相似文献
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M. B. Danard M. C. Rasmussen T. S. Murty R. F. Henry Z. Kowalik S. Venkatesh 《Natural Hazards》1984,2(2):153-171
Storm surges in the Beaufort Sea present a severe problem for navigation as well as for offshore oil drilling activities. Influence of ice cover on storm surges in the Beaufort Sea is examined making use of a numerical model as well as a set of observations.The automated shallow-water model of Henry has been modified to incorporate ice cover and is adapted to the Beaufort Sea. The leading edge of the permanent ice is calculated from the loci of identifiable points. Generalized similarity theory is employed to compute wind stresses. Simulations are made using model-predicted ice concentrations and observed ice concentrations. Ice motion is relatively small in units of model grid distance (approximately 18 km) during surges. Spherical effects are important and should be included in future adaptations of the model. Comparison of the computed surges with observed surges for eight different events showed reasonable agreement. 相似文献
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Oceanic tidal angular momentum (OTAM) is calculated for the four major tides of the Arctic Ocean, based on the tidal elevations
and current velocities from a recent two-dimensional numerical hydrodynamic model. The presented OTAM tables are meant to
be complementary to other modeling studies that use satellite altimetry (which cannot observe Arctic Ocean tides because of
ice cover and limited satellite inclinations). Although the Arctic Ocean's influence on earth rotation is, as may be expected,
relatively small, the rapid advancement of the subject now calls for such small contributions to be explicitly accounted for.
Received: 22 January 1996; Accepted: 5 December 1996 相似文献
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Environmental data are highly variable. They also include uncertainties resulting from all steps of the analytical process e. g. sampling, or sampling pre‐treatment. However, a lot of information is unfortunately often lost because only univariate statistical methods are used for data evaluation and interpretation. This neglects correlation between different pollutants and relationships among various sampling points. It is therefore necessary to apply additional methods of analysis that can accommodate such relationships. This ability is provided by the established, and by the more modern, multivariate statistical methods because they can analyze complex sets of multidimensional data. These methods are used to visualize large amounts of data and to extract latent information (e. g. differently polluted areas, dischargers, or interactions between different environmental compartments). The goal of this paper is to present the use of established statistical techniques, like cluster or factor analysis, and the progress made in basic modern techniques (e. g. cluster imaging, multiway‐partial least squares regression, projection pursuit, or information theory) and to demonstrate each with examples and illustrations. 相似文献