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81.
This paper is an attempt to contribute to the improvement of an analysis model within overall structural synthesis procedure for the multi-deck ships. The paper is organized in two parts: modeling principles and model validation. Principles of the proposed generic model formulation on the global and sub-structure levels are given in detail while the load model is briefly summarized. The basic building blocks (macro-elements and gross-elements) for the modeling of ordinary stiffened panels, combining numerical and analytical approaches, are presented and discussed w.r.t. requirements for a multi-deck structure. Different surrogates (sets of elements and ordinary macro-elements) used for equivalent modeling of large side openings are evaluated, since the reduced shear stiffness of superstructure sides has large influence on the hull girder stress distributions along the entire cross section height. The generic ship models developed using outlined principles and the basic building blocks are further validated through complex examples of a large cruise ship and a livestock carrier. On the global level, the accuracy of the generic model w.r.t. the longitudinal stress distribution over ships height is compared with a standard full ship FE model. The results confirmed that the suggested structural modeling principles, based on the generic FE model can be applied for the fast investigation of different structural topological/geometrical concepts as well as for the ordinary scantling/material optimization. 相似文献
82.
Vladan čelebonović 《Earth, Moon, and Planets》1991,54(2):145-149
A simple method for determining the thermal component of the EOS of solids under high pressure is proposed. Application to the interior of the Earth gives results in agreement with recent geophysical data. 相似文献
83.
Nikola Solarić 《Astrophysics and Space Science》1991,177(1-2):175-179
The paper deals with the automatic grid azimuth determination of an object on the earth using the electronic theodolite Kern E2 by observing the sun, a star, or a planet. The observation time and the readings of horizontal and vertical circles of the electronic theodolite enter automatically the electronic calculator Hewlett-Packard HP41CX. The calculator computes the grid azimuth of the terrestrial object and directs the observer what to do. Therefore, even a personnel without specific high education can make observations. For the solar observations it is not necessary to have an astronomical almanac, because the program computes the solar coordinates. The general input data, together with the measured ones, can be stored on a magnetic cassette and later on, if necessary, one can correct the general data and recalculate the azimuth. The method proved to be very practical in the field work. 相似文献
84.
Solić M Krstulović N Vilibić I Kuspilić G Sestanović S Santić D Ordulj M 《Marine environmental research》2008,65(5):388-404
Month-to-month fluctuations in the abundance of bacteria and heterotrophic nanoflagellates (HNF) and bacterial production, as well as various chemical (nutrients, oxygen) and physical (salinity, temperature) parameters were analysed at a station located in the open middle Adriatic Sea during one decade (1997-2006). Being influenced by both coastal waters and open Adriatic circulation in the surface layer, and by the deep Adriatic water masses in the deep layers (100 m), this station is quite suitable for detecting the environmental changes occurring in the open Adriatic Sea with respect to the circulation of its water masses and their long-term changes and anomalies. Multivariate methods were used to identify seasonal and inter-annual changes of the investigated parameters, associating observed changes to the changes in Adriatic water masses and circulation regimes. The analyses showed that bacterial abundance and production were controlled by different water mass dynamics during 1997-2001 compared to 2002-2006 period, particularly noticeable in different seasonal patterns of biological parameters. The interplay between North Adriatic Dense Water (NAdDW) and Levantine Intermediate Water (LIW) resulted in a change in the available nutrients (NAdDW is poor in orthophosphates), and as a consequence different bacterial abundance and production. A few periods were examined in detail, such as 2004, when LIW inflow was particularly strong and was accompanied by an increase of bacterial and HNF abundances, as well as of bacterial production. 相似文献
85.
Historical torrential flood events in the Kolubara river basin 总被引:1,自引:0,他引:1
86.
87.
The reduction of heavy metals (cadmium, lead and zinc) in the presence of long-chain fatty acids (lauric, oleic and linoleic) in 0.55 mol dm?3 NaCl and 0.03 mol dm?3 NaHCO3 at pH 8.7 has been studied by differential pulse polarography. The increase of the peak height of investigated metals by up to tenfold the value obtained in electrolyte without fatty acid is due to adsorption of metal ions at the electrode surface. The accumulation of metal increases with the increase of adsorption time (at potentials more positive than the reduction potential of the particular metal) and with increase of salinity. The heavy-metal adsorption depends on the concentrations of both metal ions and fatty acids. The interaction of heavy metals with the unsaturated fatty acids in the bulk and/or in the adsorbed layer at different natural interfaces could be of considerable importance in an understanding of the fate and distribution of heavy metals in the natural aquatic environment. 相似文献
88.
Vladan Čelebonović 《Earth, Moon, and Planets》1983,29(2):185-189
A model of the internal structure of Neptune has been calculated according to the Savi?-Ka?anin theory of behaviour of materials under high pressure. 相似文献
89.
Vladan čelebonović 《Earth, Moon, and Planets》1992,58(3):203-213
We present 19 examples of materials whose high pressure phase transition points can be determined within a particular classical theory of dense matter. Theoretical predictions are compared with experimental results, and some possible causes of discrepancies are discussed. 相似文献
90.
Ivanković D Pavicić J Erk M Filipović-Marijić V Raspor B 《Marine pollution bulletin》2005,50(11):1303-1313
A study was made of seasonal and spatial variability of metallothionein (MT) concentrations, determined spectrophotometrically in the soluble fraction of the digestive gland of mussels Mytilus galloprovincialis, collected between 1999 and 2001 from several coastal and estuarine locations along the central Eastern Adriatic coast (Croatia). The seasonal influence on the MT and metal concentrations (higher values in winter-spring season, than in summer-autumn season) is more pronounced than the local site-specific influence. Furthermore, within each season a significant site-specific dependence on the MT and trace metal variations can be detected. An inverse relationship of mussel condition index (CI) and temperature with MT and trace metals levels indicates the influence of food abundance and mussel annual reproductive cycle. Substantially higher concentrations of both MT and Cd were recorded in mussels inhabiting estuarine locations, possibly indicating a markedly higher Cd bioavailability at these locations. The positive correlations obtained between MT and Cd in all seasons except autumn support an argument for application of digestive gland MT as a biomarker of Cd exposure, providing evidence for assessing the most appropriate season for mussel sampling. 相似文献