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971.
Ever wider implementation of information technologies is flooding us by monitoring data. To an efficient risk management, those data have to be processed and assessed in the same rate as they are recorded and transported. Paper demonstrates some methods dealing with intrinsic, nonlinear dynamics of slope system for computerized safety assessment of monitoring time series, their modeling and early warning launching. Analysis and modeling of phase changes – i.e. specific transient states between different developmental stages of dynamics of unstable slope systems, enabled to fix new types of precursors for rock fall warning and to enhance time prediction of rock fall occurrence. Mathematically well based, novel numerical and topological methods from the toolbox of complex system theory were successfully implemented to that challenge. Their pattern-recognition ability, i.e., diagnostic sensitivity, and more realistic results of modeling of time series relevant patterns have reached beyond ranges of regularly used—both the idea- and the data-driven—methods. Moreover, results yielded by phase space analyses are in good agreement with the ones by numerical fractal analyses. Obtained results have strengthened the primary, mainly theoretically based hypothesis; the dynamics of an unstable rock slope has to be considered as behavior of nonlinear, dissipative, non-equilibrium, self-organizing complex system. Correspondingly to the theoretical assumptions, two qualitatively different types of slope system dynamics—near to equilibrium and far from equilibrium states, were identified. All field monitoring data used originated in practice of highly automated, integrated IT system of monitoring assessment, and management of rock fall hazard at sandstone rock walls in the NW Bohemia.  相似文献   
972.
The aim of this study is to isolate protoplasts from Undaria pinnatifida. Protoplasts of the alga were isolated enzymatically by using alginate lyase, which was prepared by fermenting culture of a strain Vibrio sp. 510. Monofacterial method was applied for optimizing digestion condition. The optimum condition for protoplast preparation is enzymatic digestion at 28°C for 2h using alginate lyase at the concentration of 213.36 U (8 mL) every 0.5g fresh thalline with NaCl 50 and at the shaking speed of 150 r min−1 during digestion. The protoplast yield can reach 2.62±0.09 million per 0.5 g fresh leave under the optimum condition. The enzyme activity is inhibited by Ca2+ and slightly enhanced by Fe2+ and Mn2+ at concentrations of 0.05, 0.08 and 0.10 mol L−1.  相似文献   
973.
High-resolution digital imagery of sediment cores increases researchers’ ability to examine, review, and disseminate complex and meaningful core data. The high cost of commercial core scanning systems currently limits the number of cores that are imaged. Here, we present a simple, inexpensive system that can be built in almost any laboratory environment and used to create complete core images. This system uses a stationary light source and a moving core tray (sledge) which provides for consistent lighting across multiple images. Polarized lens filters and diffuse light are used to minimize glare on the core surface. Our system also repurposes professionally engineered exercise equipment which, provides for precise core and camera movement. Once images are taken, stitching software is used to create the final core image. While there are many stitching programs on the market, none are explicitly aimed at stitching together many images in a single, straight line. We evaluated seven of the most common stitching programs and identified Hugin as the most useful for creating completed core images.  相似文献   
974.
975.
Anomalous induction across Europe   总被引:1,自引:0,他引:1  
Summary Using real induction vector data, collected at 958 European observation sites, together with our data from the Bohemian Massif and the West Carpathians, we have generated a contour map of the transfer function TF1 (corresponding to transfer function A in Wiese's relation). Only the zero contour is retained and shown on the map. It clearly marks the main anomalous induction zones, related to internal structural inhomogeneities, across Europe.  相似文献   
976.
The Chernobyl plume contaminated vast lands of Europe with radiocaesium (137Cs) in 1986 because of the deposition of radionuclides on the ground by wet and dry deposition processes. Nevertheless, in a nuclear emergency, contamination data may be very sparse and there is need to make rapid and scientifically supported decisions. Here we analyze the rainfall field, an important precursor of the wet deposition, during the passage of the plume. Thus, estimating rainfall spatial variability can help to identify possible contaminated areas and associated risks when rainfall exceeded a given threshold. In this paper, we show that the conditional probabilities of exceeding threshold rainfall values could be spatially assessed using the mutual benefits of linking geostatistical and geographical information system (GIS) to quantify the evaluation of the risk involved in decision making. In particular, the non-parametric geostatistic technique, termed Indicator Kriging (IK), enables one to efficiently estimate the probability that the true value exceeds the threshold values by means of the indicator coding transform. Afterward, GIS has been used to find the areas probably affected by wash-out (probability >0.5 that rainfall is above a certain threshold). The experimental study has been focused on a test site in Beneventan agroecosystem (Southern Italy) to model the spatial uncertainty over a continuous area from sparse rainfall data. This enabled to generate probability maps delineating area potentially affected by to contamination to be monitored after wet deposition of Chernobyl releases.  相似文献   
977.
Using the teleparallel gravity versions of the Einstein and Landau–Lifshitz’s energy and/or momentum complexes, I obtain the energy and momentum of the universe in viscous Kasner-type cosmological models. The energy and momentum components (due to matter plus field) are found to be zero and this agree with a previous work of Rosen and Johri et al., who investigated the problem of the energy in Friedmann–Robertson–Walker (FRW) universe. The result that the total energy and momentum components of the universe in these models is zero same as Bergmann–Thomson’s energy–momentum and props the viewpoint of Tryon. Rosen found that the energy of the FRW space–time is zero, which agrees with the studies of Tryon. PACs Numbers: 04.20.-q; 04.50.+h An erratum to this article is available at .  相似文献   
978.
Field equations are obtained with the aid of higher dimensional Bianchi type-I cosmological model in scale covariant theory of gravitation in the context of cosmic strings. We present here isotropic and anisotropic solutions of the field equations and some physical implications of these solutions are briefly discussed.  相似文献   
979.
The linear theory and N-body simulations are used to present a new, alternative model of the galaxy A0035-324 (the “Cartwheel”), which is the most striking example of the relatively small class of ring galaxies. The model is based on the gravitational Jeans-type instability of both axisymmetric (radial) and nonaxisymmetric (spiral) small-amplitude gravity perturbations (e.g., those produced by spontaneous disturbances) of a dynamically cold subsystem (identified as the gaseous component) of an isolated disk galaxy. The simplified model of a galaxy is used in which stars (and a dark matter, if it exists at all) do not participate in the disk collective oscillations and just form a background charge. In the theory presented here, a case for both purely radial solutions and purely spiral solutions to the equations of motion of an infinitesimally thin gaseous disk is made, which is associated with both a radial density wave and a dominant spiral density wave which propagate outwards creating a rough ring and a number of spiral arms. Through three-dimensional numerical simulation of a collisionless set of many particles, I associate these gravitationally unstable axisymmetric waves and nonaxisymmetric waves with growing clumps of matter which take on the appearance of a ring and spokes of mass blobs.  相似文献   
980.
In this paper, using the energy definition in MØller’s tetrad theory of gravity we calculate the total energy of the universe in Bianchi-type I cosmological models which includes both the matter and gravitational fields. The total energy is found to be zero and this result agrees with a previous works of Banerjee and Sen who investigated this problem using the general relativity version of the Einstein energy-momentum complex and Xulu who investigated same problem using the general relativity versions of the Landau and lifshitz, Papapetrou and Weinberg’s energy-momentum complexes. The result that total energy of the universe in Bianchi-type I universes is zero supports the viewpoint of Tryon.  相似文献   
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