Detection of ground ice using ground penetrating radar method     

Gennady M. Stoyanovich  Viktor V. Pupatenko  Yury A. Sukhobok 《寒旱区科学》2015,7(5):541-546

The paper presents the results of a ground penetrating radar (GPR) application for the detection of ground ice. We combined a reflection traveltime curves analysis with a frequency spectrogram analysis. We found special anomalies at specific traces in the traveltime curves and ground boundaries analysis, and obtained a ground model for subsurface structure which allows the ground ice layer to be identified and delineated.  相似文献   

Propagation of vibrations in thawing deep seasonally frozen soils in railway subgrade     

Gennady M. Stoyanovich  Viktor V. Pupatenko 《寒旱区科学》2015,7(5):534-540

In this study, in-situ testing results are given, and the analytical relationship of the vibrations' amplitudes inside an embankment by the thawing of the subgrade surface of seasonably deep frozen soils is provided. The peculiarities of the vibration waves' propagation during the springtime thawing of soils compared to those during the summertime period and the correlation of the vibrations with the under-rail basement modulus of elasticity are defined.  相似文献   

Industrial specialization and economic performance: A case of Czech microregions     

Jan Ženka  Josef Novotný  Ondřej Slach  Viktor Květoň 《Norsk geografisk tidsskrift. Norwegian journal of geography》2015,69(2):67-79

An influential body of literature suggests that economic diversity rather than specialization fuels the economic performance of regions and nations. The authors argue that this hypothesis has no universal applicability and that a more differentiated view is needed. In particular, historical specificity of the local environment and structural characteristics of regional economies should be taken into account. They focus on the effects of industrial specialization on economic performance and the vulnerability of Central European post-communist regions, namely Czech microregions with less than 200,000 inhabitants. They examine whether the economic performance and vulnerability of these regions is fuelled rather by industrial specialization or diversity when controlling for other potential determinants of regional economic performance. Their findings show that the dependence of Czech regions on manufacturing correlates with higher economic performance but also with higher regional vulnerability. In addition, industrial specialization within manufacturing was found to be instrumental for the economic performance of regions with high dependence on manufacturing. With a decreasing share of employment in manufacturing, industrial diversity rather than specialization becomes more valuable for the economic performance of Czech regions.  相似文献   

Seismostratigraphy and sedimentation environment on the shelf and continental slope of Peter the Great Bay (Sea of Japan)     

V. N. Karnaukh  B. Ya. Karp  I. B. Tsoy 《Oceanology》2007,47(2):261-272

The results of a single channel seismic reflection survey and of a micropaleontological examination of diatom remains in bottom sediment samples on the shelf and continental slope of the Peter the Great Bay area are presented. The composition and age of the sedimentary layer were studied using integrated seismic, micropaleontological and geological data. The continental slope was formed not later than at the beginning of the Early Miocene. The slope is covered with Middle Miocene-Pliocene sediments. The sedimentary thickness on most of the slope is 0.2–0.4 s. The maximum thickness (0.8–1.0 s) is observed within the areas of submarine canyons and valleys. The thickness of the Early Miocene-Pliocene sediments on the shelf is 0.2–0.4 s. On the shelf break and in a southwest-trending trough of the acoustic basement, it increases up to 1.0 s. Two uncomformities were identified in the sediments of the shelf area. The proposed age of the upper uncomformity is 10.0–8.5 My B.P.; it represents the result of a global sea level fall. The age of the lower uncomformity is unknown.  相似文献   

Stratal composition and stratigraphic organization of stratal elements in an ancient deep‐marine basin‐floor succession,Neoproterozoic Windermere Supergroup,British Columbia,Canada          下载免费PDF全文

Viktor Terlaky  Jonathan Rocheleau  Robert William Charles Arnott 《Sedimentology》2016,63(1):136-175

Despite a globally growing seismic and outcrop analogue data set, the detailed (centimetre to decametre) internal stratal make up of deep‐marine basin‐floor ‘channelized‐lobe’ strata remain poorly known. An ancient analogue for modern, mixed‐sediment, passive margin, deep‐marine basin‐floor fans is the well‐preserved Neoproterozoic Upper and Middle Kaza groups in the southern Canadian Cordillera. This succession is a few kilometres thick and comprises six sedimentary facies representing deposition from different kinds of sediment‐gravity flows. Representative lateral and vertical assemblages of one or more of these facies comprise six stratal elements, including: isolated scours, avulsion splays, feeder channels, distributary channels, terminal splays, and distal and off‐axis fine‐grained turbidite units. The internal characteristics of the various stratal elements do not differ from more distal to more proximal settings, but the relative abundance of the various stratal elements does. The difference in relative abundance of stratal elements in the kilometre‐scale stratigraphy of the Kaza Group results in a systematic upward change in architecture. The systematic arrangement of the stratal elements within the interpreted larger bodies, or lobes, and then lobes within the basin‐floor fan, suggests a hierarchical organization. In this article a hierarchy is proposed that is based on avulsion but, also importantly, the location of avulsion. The proposed avulsion‐based hierarchical scheme will be a useful tool to bridge the scalar gap between outcrop and seismic studies by providing a single stratigraphic framework and terminology for basin‐floor stratal elements.  相似文献   

Using terrestrial LiDAR to measure water erosion on stony plots under simulated rainfall     

Li Li  Mark A. Nearing  Mary H. Nichols  Viktor O. Polyakov  Michelle L. Cavanaugh 《地球表面变化过程与地形》2020,45(2):484-495

Terrestrial LiDAR scanning (TLS) technology is widely used to detect terrain elevation changes. This study examines the potential use of terrestrial LiDAR to measure erosion on small experimental plots at high resolution. Multitemporal TLS scans were conducted at six positions around plots (12 m²) with three slope treatments through 11 simulated rainfall applications. Surface elevation changes were quantified by comparing scans between rainfall simulations, and elevation changes greater than the level of detection were used to obtain volumetric change estimations. Erosion mass was estimated both by using soil bulk density and the density of sediment collected in runoff, and then compared to the erosion estimated from the runoff samples. Results showed: (1) with the aid of fixed reference controls in the form of concrete target surfaces of varying roughness, registration accuracy was better than 1 mm and mean level of change detection was less than 2.2 mm; (2) the average absolute relative errors of TLS-estimated eroded mass ranged from 6.8% to 31.8%, with greater values on 5% slope; (3) the TLS-estimated erosion accuracy was affected by erosion magnitude, the utilized material density and number of scan positions, and a grid size of 10 mm was found to be appropriate for this scale to estimate the volumetric changes; (4) the number of scan positions could be reduced to three while not significantly impacting volumetric change estimations; and (5) elevating the scanner resulted in much better accuracy for eroded mass estimations. This study suggests that using LiDAR to monitor soil erosion at the plot scale is feasible, and provides guidance about the level of accuracy one might expect in doing so. © 2019 John Wiley & Sons, Ltd.  相似文献   

On the computation of area probabilities based on a spatial stochastic model for precipitation cells and precipitation amounts     

Bj?rn?KriescheEmail author  Antonín?Koubek  Zbyněk?Pawlas  Viktor?Bene?  Reinhold?Hess  Volker?Schmidt 《Stochastic Environmental Research and Risk Assessment (SERRA)》2017,31(10):2659-2674

A main task of weather services is the issuing of warnings for potentially harmful weather events. Automated warning guidances can be derived, e.g., from statistical post-processing of numerical weather prediction using meteorological observations. These statistical methods commonly estimate the probability of an event (e.g. precipitation) occurring at a fixed location (a point probability). However, there are no operationally applicable techniques for estimating the probability of precipitation occurring anywhere in a geographical region (an area probability). We present an approach to the estimation of area probabilities for the occurrence of precipitation exceeding given thresholds. This approach is based on a spatial stochastic model for precipitation cells and precipitation amounts. The basic modeling component is a non-stationary germ-grain model with circular grains for the representation of precipitation cells. Then, we assign a randomly scaled response function to each precipitation cell and sum these functions up to obtain precipitation amounts. We derive formulas for expectations and variances of point precipitation amounts and use these formulas to compute further model characteristics based on available sequences of point probabilities. Area probabilities for arbitrary areas and thresholds can be estimated by repeated Monte Carlo simulation of the fitted precipitation model. Finally, we verify the proposed model by comparing the generated area probabilities with independent rain gauge adjusted radar data. The novelty of the presented approach is that, for the first time, a widely applicable estimation of area probabilities is possible, which is based solely on predicted point probabilities (i.e., neither precipitation observations nor further input of the forecaster are necessary). Therefore, this method can be applied for operational weather predictions.  相似文献   

Are There Differences in the Response of Natural Stand and Plantation Biomass to Changes in Temperature and Precipitation? A Case for Two-needled Pines in Eurasia     

USOLTSEV Vladimir Andreevich  SHOBAIRI Seyed Omid Reza  TSEPORDEY Ivan Stepanovich  AHRARI Amirhossein  ZHANG Meng  SHOAIB Ahmad Anees  CHASOVSKIKH Viktor Petrovich 《资源与生态学报(英文版)》2020,11(4):331-341

A comparative discussion of the advantages and disadvantages of natural stands and plantations, including in terms of their productivity and stability, began from the moment of the first forest plantings and continues to this day. In the context of the progressive replacement of natural forests by plantations due to deforestation, the question of how will change the carbon storage capacity of forest cover when replacing natural forests with artificial ones in a changing climate becomes extremely relevant. This article presents the first attempt to answer this question at the transcontinental level on a special case for two-needled pine trees (subgenus Pinus L.). The research was carried out using the database compiled by the authors on the single-tree biomass structure of forest-forming species of Eurasia, in particular, data of 1880 and 1967 of natural and plantation trees, respectively. Multi-factor regression models are calculated after combining the matrix of initial data on the structure of tree biomass with the mean January temperature and mean annual precipitation, and their adequacy indices allow us to consider them reproducible. It is found that the aboveground and stem biomass of equal-sized and equal-aged natural and plantation trees increases as the January temperature and precipitation rise. This pattern is only partially valid for the branches biomass, and it has a specific character for the foliage one. The biomass of all components of plantation trees is higher than that of natural trees, but the percent of this excess varies among different components and depends on the level of January temperatures, but does not depend at all on the level of annual precipitation. A number of uncertainties that arose during the modeling process, as well as the preliminary nature of the obtained regularities, are noted.  相似文献   

Spatially constrained regionalization with multilayer perceptron     

Michael Govorov  Giedr&#x; Beconyt&#x;  Gennady Gienko  Viktor Putrenko 《Transactions in GIS》2019,23(5):1048-1077

In this article, multilayer perceptron (MLP) network models with spatial constraints are proposed for regionalization of geostatistical point data based on multivariate homogeneity measures. The study focuses on non‐stationarity and autocorrelation in spatial data. Supervised MLP machine learning algorithms with spatial constraints have been implemented and tested on a point dataset. MLP spatially weighted classification models and an MLP contiguity‐constrained classification model are developed to conduct spatially constrained regionalization. The proposed methods have been tested with an attribute‐rich point dataset of geological surveys in Ukraine. The experiments show that consideration of the spatial effects, such as the use of spatial attributes and their respective whitening, improve the output of regionalization. It is also shown that spatial sorting used to preserve spatial contiguity leads to improved regionalization performance.  相似文献   

The Stubenberg meteorite—An LL6 chondrite fragmental breccia recovered soon after precise prediction of the strewn field          下载免费PDF全文

Addi Bischoff  Jean‐Alix Barrat  Kerstin Bauer  Christoph Burkhardt  Henner Busemann  Samuel Ebert  Michael Gonsior  Janina Hakenmüller  Jakub Haloda  Dennis Harries  Dieter Heinlein  Harald Hiesinger  Rupert Hochleitner  Viktor Hoffmann  Melanie Kaliwoda  Matthias Laubenstein  Colin Maden  Matthias M. M. Meier  Andreas Morlok  Andreas Pack  Alexander Ruf  Philippe Schmitt‐Kopplin  Maria Schönbächler  Robert C. J. Steele  Pavel Spurný  Karl Wimmer 《Meteoritics & planetary science》2017,52(8):1683-1703

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