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The parallel computing capabilities of GPUs have a significant impact on computationally intensive iterative tasks. Offloading part or all of the deep learning tasks from the CPU to the GPU for execution is mainstream. However, a large number of redundant iterative calculations exist in the iterative process of computing tasks. Therefore, we propose a GPU-based distributed incremental iterative computing architecture that can make full use of distributed parallel computing and GPU memory structure. The architecture supports deep learning and other computationally intensive iterative applications by optimizing data placement and reducing redundant iterative calculations. To support block-based data partitioning and coalesced memory access on GPUs, we propose GDataSet, an abstract data set. The GPU incremental iteration manager called GTracker is designed to be responsible for GDataSet cache management on the GPU. In order to solve the limitation of on-chip memory size, we propose a variable sliding window mechanism. It improves the hit rate of cache access and the speed of data access by realizing the best block arrangement between on-chip memory and off-chip memory. Besides, a communication channel based on an incremental iterative model is designed to support data transmission and task communication in cluster computing. Finally, we implement the proposed architecture based on Spark 2.4.1 and CUDA 10.0. Comparative experiments with widely used computationally intensive iterative applications (K-means, LSTM, etc.) show that the incremental iterative acceleration architecture can significantly improve the efficiency of iterative computing.

As a complex process, an underwater explosion is affected by different factors. Shock factors are variables used to characterize the severity of a shock based on scaling laws, which are con...

Part II of this paper is focused on the dynamic response of a steel plate of the centrifuge model which is fixed on the container. This plate is 5 cm thick, allowing for non-destructive elastic response to all the 19 blasts. Three accelerators and 10 sets of strain gauges are installed on the plate to monitor the acceleration and deformation histories induced by shock waves and bubble oscillations. This article presents the characteristic values measured for shock waves and bubble oscillations response. The detailed information can be found in a database available on the web. In order to obtain the correct acceleration time history, the cut-off frequency of low-pass filtering by Fourier transformation was applied. The results indicated that the acceleration and strain induced by shock wave was nearly unaffected by the increasing gravity, while the effect of gravity has remarkable influence on those induced by bubble oscillation. A preliminary study of comparing the measured dynamic response with numerical simulations has been carried out using ANSYS LS-DYNA. The results captured the dynamic response in terms of characteristics and trends, but deviated in magnitude due the theoretical and technological limitations involved in both the physical and numerical models. It certainly deserves further studies.

Muti-baseLine SAR tomography can be used on 3D reconstruction of urban building based on SAR images acquired. In the near future, it is expected to become an important technical tool for urban multi-dimensional precision monitoring. For the moment，There is no effective method to verify the accuracy of tomographic SAR 3D point cloud of urban buildings. In this paper, a new method based on terrestrial Lidar 3D point cloud data to verify the accuracy of the tomographic SAR 3D point cloud data is proposed, 3D point cloud of two can be segmented into different facadeds. Then facet boundary extraction is carried out one by one, to evaluate the accuracy of tomographic SAR 3D point cloud of urban buildings. The experience select data of Pangu Plaza to analyze and compare, the result of experience show that the proposed method that evaluating the accuracy of tomographic SAR 3D point clou of urban building based on lidar 3D point cloud is validity and applicability

Compressive sensing theory can recover the original signal from little observation data, by means of the non-adaptive measurement far below Nyquist sampling and the optimization method. Due to the number of track is limited and the uneven distribution of tracks, the traditional method is difficult to image effectively in the practical application, while the compressive sensing theory by tomoSAR three-dimensional imaging (MUSIC, APES, etc.) can solve the problem easily, and it can realize high resolution imaging of SAR in the height direction. This paper applied the Generalized Orthogonal Matching Pursuit (GOMP) algorithm to the SAR tomography imaging, which can accurately reconstruct the signal in the height direction. Meanwhile, in this paper, 14 images of ascend track from which is “TerraSAR-X” HH polarization mode in Beijing during the period of 2011–2014 were taken as the test data, and Beijing pangu7 star hotel is taken as the research target. Finally, the result indicates that our algorithm is better than typical Orthogonal Matching Pursuit (OMP) algorithm.

Urban building outline is not only a very important land cover type, but also the key of studying urban building. It is significance on urban construction planning and natural disasters monitoring. This paper discussed the method for building information extracting according to high-resolution SAR coherence image. Through theoretical analysis and test verifying, it had obtained a better effect for extracting the buildings’ profiles or top figures from the coherence image, which often expressed as ‘L’-style top structures from SAR SLC image. This method has been proved the further potential in extracting urban buildings’ structure and profile information, and has some extent of reference means.

This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using a 450 g-t geotechnical centrifuge apparatus. Ten centrifuge model tests were completed with various ranges of explosive mass, burial depth and centrifuge accelerations. Eleven accelerometers were installed to record the acceleration response in sand. The dimensions of the explosion craters were measured after the tests. The results demonstrated that the relationship between the dimensionless parameters of cratering efficiency and gravity scaled yield is a power regression function. Three specific function equations were obtained. The results are in general agreement with those obtained by other studies. A scaling law based on the combination of the π terms was used to fit the results of the ten model tests with a correlation coefficient of 0.931. The relationship can be conveniently used to predict the cratering effects in sand. The results also showed that the peak acceleration is a power increasing function of the acceleration level. An empirical exponent relation between the proportional peak acceleration and distance is proposed. The propagation velocity of blast waves is found to be ranged between 200 and 714 m/s.

The teaching presupposition in the simple horizon is mechanical reflex to teaching regularity. The presupposition become “track”, the teaching become the process along the “track”. The Teaching presupposition based on complex theory, examine and reconstruction realizes the horizon conversion from simple to complex.

Based on the full understanding of the evaluation index system of Government Information Portal Site in and abroad, this paper inspects the characteristics of Government Information Portal development of local government of all levels in Shanxi and Ningxia Province. Investigating the needs of Government Information Portal Site service by the public, it puts forward a whole new index system of service function evaluation of Government Information Portal Site to the public. During the calculation of index weight, it utilizes gray correlation analysis to avoid the disadvantages caused by using AHP with subjective experiences, by using the evaluation index system to evaluate the Government Information Portal Site of ten local governments in Shanxi and Ningxia Province, which improves the reliability of evaluation results.