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151.
152.
Issues of the formation and recording of the spatial and angular distributions of thermal radio radiation of rainfall in the microwave range are discussed. The thermal radio-frequency radiative transfer in a threedimensional rain cell is simulated numerically with a different rainfall rate, taking into account the nonspherical shape of falling raindrops and their size distribution. The role of the three-dimensional inhomogeneity of rainfall fields in the formation of a field of their inherent thermal radio radiation in the microwave range is revealed.  相似文献   
153.
154.
There is lack of information regarding ammonia nitrogen (AN), (i.e. NH3-N) decay rate of river water in tropical regions like Malaysia. AN decay rate is a very important kinetic parameter to estimate NH3-N, nitrate nitrogen (NO3-N) and dissolved oxygen concentrations of river water by using computer models. This study presents determination of ammonia nitrogen decay rate of river water in the tropical environment of Malaysia. A laboratory flume was used to conduct twelve experiments. The flume was used to represent the turbulent condition of a typical river. Ammonia nitrogen decay rate for the tropical environment of Malaysia was observed to be between 0.194 and 0.554 per day. Median value of AN decay rate was 0.26 per day, which is slightly lower than the global median value of 0.295 per day. To check the accuracy of flume experiments, the AN decay rate of Pusu River obtained from the flume experiment was used to calibrate and validate ammonia nitrogen concentration of the river by using water quality analysis and simulation program (WASP). Very good calibration and validation results were achieved, which substantiated the accuracy of the flume experiments.  相似文献   
155.
Lithology and Mineral Resources - Upper Paleozoic sections in Taimyr comprise genetic rock complexes of different zones: deep-water shelf; offshore transition zone; shoals, deltas, and beaches of...  相似文献   
156.
Properly designed precast concrete cladding could potentially provide lateral stiffness, ductility, and energy dissipation for an overall building structure, especially during earthquakes. This paper describes a set of advanced connections that take advantage of the interaction between facade panels and structure (mainly due to horizontal interstorey drift) to dissipate energy, thereby reducing the response of the main structure. The results of an experimental program to characterize the hysteretic behaviour of advanced connections are presented. Design equations for the advanced connections are then calibrated against the test results, and the corresponding design charts are presented. It is anticipated that this research will lead to innovative ways of viewing the entire cladding system of a building.  相似文献   
157.
Izvestiya, Atmospheric and Oceanic Physics - A method for retrieving sea wave spectra from space images of high spatial resolution has been developed for various conditions of wave generation based...  相似文献   
158.
The onset of the confinement transition in the early universe is studied within the Friedmann model. Exploiting a bag model equation of state for the deconfined matter, which is generalized to include also metastable states, the possibility of a mini-inflationary epoch is demonstrated. A criterion of metastability is derived to estimate parameters of this mini-inflation.  相似文献   
159.
The remnants of former tin-streaming channels on the North Teign River, Dartmoor have been investigated using techniques adopted from palaeohydrology, sedimentology, and environmental chemistry. the pattern of multiple streaming channels in the lower reaches, and a single channel in the upper reaches coincides with a reduction of potential stream power from 250 Wm−2 at a drainage area of 8.7 km2. the streaming sections were engineered to maximize the efficiency to separate cassiterite (SnO2) from its gravel matrix, and the palaeohydraulic properties of channels suggests that sorting was most efficient for the sand and fine gravel size ranges. This was confirmed when the residual tin content of streaming-sediments was assessed. Residual levels of tin were found only in the silt fraction (<63 μm).  相似文献   
160.
Modelling and extracting 3D geographical data presents numerous challenges that require continual research to attempt to evolve an efficient, reliable and accurate solution. LiDAR data capture and analysis has become a preferred acquisition choice for elevation data because the resulting quality and level of detail far exceeds traditional methods for large survey areas. As with any data collection system, LiDAR is prone to errors. Analysing these errors, ascertaining causes and producing error correction strategies is vital if accurate and confident results are to be obtained. Eight years of LiDAR datasets (from 1998 to 2005) have been closely analysed for a large coastal area of South Wales. This article provides a detailed and accurate summary of the identified LiDAR data issues and subsequent errors which affect the accuracy of end products such as Digital Surface Models (DSMs).  相似文献   
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