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Solution for distributed model of Groundwater System with PCG2 for Naolihe Basin in Sanjiang Plain

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Journal of Northeast Agricultural University(English Edition) 2009年第1期16卷 59-63页

作者： GUO Longzhu WANG Fulin PENG Shengmin College of Agriculture Northeast Agricultural University Harbin 150030 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Engineering College Northeast Agricultural University Harbin 150030 China

PCG2 （Preconditioned Conjugate-Gradient Method 2）, the most popular mothod used in groundwater field, was used to solve the distributed model of large-scale groundwater system. Its principle and effect was analyzed mathematically, and verified by some specific examples. Numerical results acquired by PCG2 are accurate, it demonstrates that PCG2 is effective on methodology itself and man-ralated operation. So PCG2 is worthy of popularizing in the area of groundwater system for numerical analysis.

关键词： PCG2 groundwater distributed model accuracy

A distributed Soil Erosion and Sediment Transport Sub-model in Non-point Source Pollution and Its Application in Guishui Watershed

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Journal of Resources and Ecology 2010年第3期1卷 237+231-236页

作者：夏军薛金凤中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 武汉大学动力与机械学院水质科学与技术系武汉430072

官厅水库妫水地区土壤侵蚀较为严重。为控制妫水地区的土壤流失非点源污染,本文建立了一个参数较少、便于应用的分布式土壤侵蚀和泥沙输移子模型。该模型由USLE模型和泥沙输移模型组成。首先,本研究确定了USLE中各因子的计算公式,用该... 详细信息

官厅水库妫水地区土壤侵蚀较为严重。为控制妫水地区的土壤流失非点源污染,本文建立了一个参数较少、便于应用的分布式土壤侵蚀和泥沙输移子模型。该模型由USLE模型和泥沙输移模型组成。首先,本研究确定了USLE中各因子的计算公式,用该模型计算土壤流失。然后,将流域概化为河网,利用曾提出的应用于经Laplace变换和逆变换求得的一维水质迁移转化方程的解中的面积汇污系数和S曲线之间的关系,推导得到了分布式泥沙输移模型。最后,从妫水河流域土壤图、土地利用图中提取地理信息,以DEM为依据,研究了该模型在妫水河流域的应用。结果表明,该模型不仅可用于研究非点源泥沙污染,而且可用于研究流域内土壤侵蚀的空间分布,为实现农业最佳管理提供科学依据。妫水流域土壤流失主要来自坡度较大、地表植被覆盖差的丘陵和山地,控制土壤流失应该将重点放在该流域内的丘陵和山地上。

关键词： nonpoint source pollution distributed model GIS Guanting Reservoir Guishui River

distributed modeling of direct solar radiation on rugged terrain of the Yellow River Basin

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Journal of Geographical Sciences 2005年第4期15卷 439-447页

作者： ZENG Yan QIU Xinfa LIU Changming JIANG Aijun Jiangsu Institute of Meteorological Sciences Nanjing 210008 China Department otGeospatial Information Sciences Nanjing University of Information Science and TechnologyNanjing 210044 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Due to the influences of local topographical factors and terrain inter-shielding, calculation of direct solar radiation （DSR） quantity of rugged terrain is very complex. Based on digital elevation model （DEM） data and meteorological observations, a distributed model for calculating DSR over rugged terrain is developed. This model gives an all-sided consideration on factors influencing th a resolution of 1 km × 1 km for thDSR. Using the developed model, normals of annual DSR quantity wie Yellow River Basin was generated, with DEM data as the general characterization of terrain. Characteristics of DSR quantity influenced by geographic and topographic factors over rugged terrain were analyzed thoroughly. Results suggest that： influenced by local topographic factors, i.e. azimuth, slope and so on, and annual DSR quantity over mountainous area has a clear spatial difference; annual DSR quantity of sunny slope （or southern slope） of mountains is obviously larger than that of shady slope （or northern slope）. The calculated DSR quantity of the Yellow River Basin is provided in the same way as other kinds of spatial information and can be employed as basic geographic data for relevant studies as well.

关键词： direct solar radiation (DSR) rugged terrain digital elevation model (DEM) distributed model Yellow River Basin

Estimation of glacier ice storage in western China constrained by field ground-penetrating Radar surveys

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Advances in Climate Change Research 2022年第3期13卷 359-374页

作者： Peng-Bin LIANG Li-De TIAN Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650091China

Recent decades have witnessed the accelerated retreat of alpine glaciers,which likely portends a decline in the glacial ice melt on which large downstream populations rely for ***,estimating water storage in alpine glaciers is critical for predicting the trend of glacier *** study compiled a rich set of ice thickness observations for glaciers of varying sizes in western *** here presented a first-order assessment of the various errors involved in interpreting ice thickness from ground-penetrating radar(GPR)*** empirical Bayesian kriging(EBK)method was used for ice thickness interpolation and volume *** then established a new volume-scaling law specific to western China glaciers based on these 36 volume-area *** together with the Second Chinese Glacier Inventory(SCGI),we obtain a regional volume estimate of 4451±298 km^(3).By comparison,we believed that this result is the most reliable estimate of the total ice storage in western China and more reliably predicts gross glacier ***,our results show that the method of glacier division can strongly affect the total volume estimation,which previous studies *** emphasizes the need for more surveyed glaciers data and more accurate glacier inventory to improve the evaluation of the climate impact on glacier melting water resources and to help ensure the future survival of these alpine glaciers.

关键词： Ground-penetrating radar Glacier thickness survey Glacier volume volume-area scaling law distributed model Western China

The effect of evaporator operating parameters on the flow patterns inside horizontal pipes

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Journal of Thermal Science 2011年第4期20卷 324-331页

作者： Lige Tong Haiyan Li Li Wang Xinxing Sun Yunfei Xie Department of Thermal Science and Energy Engineering University of Science and Technology Beijing Beijing 100083 China

A general and simple model for simulating the steady state behaviors of Mr-m-refrigerant fin-and-tube evaporator is introduced with the focus on the detailed flow patterns inside the tubes. In order to simulate the heat transfer between air and the working fluid, the evaporator is divided into a number of control volumes. Empirical correlations from literature were also adopted to estimate the void fraction, the internal and external heat transfer coefficients, and the pressure drops. Simulations were performed to study the effects of varying inlet air temperature, refrigerant mass flow rate and evaporation pressure on the flow patterns inside the horizontal pipe of the evaporator. The simulation results indicate that the proposed model can be used to predict flow patterns well. The predicted results of the model agree well with experimental results, the difference is within ±3% for the cooling capacity, and is within ±0.2% for refrigerant evaporation temperature.

关键词： evaporator distributed model two-phase zone flow pattern

A Novel Mixed Precision distributed TPU GAN for Accelerated Learning Curve

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Computer Systems Science & Engineering 2023年第7期46卷 563-578页

作者： Aswathy Ravikumar Harini Sriraman School of Computer Science and Engineering Vellore Institute of TechnologyChennai600127India

Deep neural networks are gaining importance and popularity in applications and *** to the enormous number of learnable parameters and datasets,the training of neural networks is computationally *** and distributed computation-based strategies are used to accelerate this training *** Adversarial Networks(GAN)are a recent technological achievement in deep *** generative models are computationally expensive because a GAN consists of two neural networks and trains on enormous ***,a GAN is trained on a single *** deep learning accelerator designs are challenged by the unique properties of GAN,like the enormous computation stages with non-traditional convolution *** work addresses the issue of distributing GANs so that they can train on datasets distributed over many TPUs(Tensor Processing Unit).distributed learning training accelerates the learning process and decreases computation *** this paper,the Generative Adversarial Network is accelerated using the distributed multi-core TPU in distributed data-parallel synchronous *** adequate acceleration of the GAN network,the data parallel SGD(Stochastic Gradient Descent)model is implemented in multi-core TPU using distributed TensorFlow with mixed precision,bfloat16,and XLA(Accelerated Linear Algebra).The study was conducted on the MNIST dataset for varying batch sizes from 64 to 512 for 30 epochs in distributed SGD in TPU v3 with 128×128 systolic *** extensive batch technique is implemented in bfloat16 to decrease the storage cost and speed up floating-point *** accelerated learning curve for the generator and discriminator network is *** training time was reduced by 79%by varying the batch size from 64 to 512 in multi-core TPU.

关键词： Data parallel distributed model generative model learning curve mixed precision

Hydrological modeling of Aguibat Ezziar Watershed (Morocco), Comparative Study of Two Different Hydrological models

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Journal of Geographic Information System 2016年第1期8卷 50-56页

作者： Mourad Khattatı Mostapha Serroukh Ismail Rafık Hakim Mesmoudı Hassane Brırhet Yassine Bouslıhım Fatima Hara Research Team ERGO Faculty of Science Abdelmalek Essaadi University Tetouan Morocco Faculty of Science and Technology Sidi Mohammed Ben Abdellah University Fes Morocco Faculty of Science and Technology 1st Hassan University Settat Morocco Scientific Institute Mohammed V University Rabat Morocco

This study aims to compare the performance of two hydrological models, conceptual (HEC-HMS) and spatial (ATHYS) on the Aguibat Ezziar watershed. The comparative analysis is based on the performances of simulation in terms of Nash-Sutcliffe and RSR. The study requires the collection of a series of data as inputs models namely rainfall data, water quantity, soil occupation, DTM and requires also a calibration in order to evaluate these models in validation phase. The simulation results were obtained from the validation phase aiming to replicate the operation of watershed Aguibat Ezziar, and present a suitable adjustment perspective of the observed hydrograph. These results show that the objective is achieved and a model distributed like ATHYS plays an effective role to improve the efficiency and present a high advantage in anticipation of runoff volume comparing with other models.

关键词： Spatial modeling distributed model Conceptual model Hydrology ATHYS HEC-HMS

Assessment of the Sensitivity of Soil Parameters in Sediment Production in the Ichu River Experimental Basin

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Journal of Environmental Science and Engineering(A) 2023年第1期12卷 1-13页

作者： Ivan A.Ayala Bizarro Yunior AHuaman Paitan Marco Lopez Barrantes Jorge Ortega Vargas Omar Caballero sanchez Abdon Olivera Quintanilla Cesar Jurado Mancha Jessica Zuniga Mendoza Cesar Lifonzo Salcedo Faculty of Civil Engineering National University of HuancavelicaHuancavelica 09001Peru Faculty of Civil Engineering National University of San Cristobal of HuamangaAyacucho 05000Peru

This research aims to determine how much is the sensitivity of soil parameters in the production of sediments through the model distributed at the level of cells in the Ichu River Basin,which is located in the Andes of Peru,with an approximate surface area of 1,380.17 km2,corresponding to the control section and tributary to the Mantaro ***,for the evaluation of sensitivity determine the amount of sediments of the textures:silt,clay and *** achieve the objectives that have been raised in this research has been used the conceptual distributed hydrological model TETIS v9.1,which has been calibrated and validated using the climatic variables that are recorded at the hourly level in six weather stations and a hydrometric station,synthetic precipitation was also used withsatellite stations(CHIRPS)of the Climate Hazards Group that has registered with a grid of 0.05 degrees of resolution,from 1981 to the *** determine the solid component,the TETIS v9.1 model uses the equations developed in the CASCade 2 Dimensional SEDimentation model(CASC2D-SED)that presents conceptual approaches with physical *** sediment processes on slopes this CASC2D-SED model simulates in two dimensions,as well as helps to determine the quantification of sediments at any point in the basin considering all physical *** the other hand,the OpenLandMap data portal has been used for land cover data of the K factor corresponding to the susceptibility of the soil that can suffer losses due to ***,the Moderate Resolution Imaging Spectroradiometer(MODIS)observation system to determine the Normalized Difference Vegetation Indices(NDVI)for the culture factor *** parameter P corresponding to the conservation technique applied,has been developed using remote sensing techniques using the Google Earth Engine(GEE)***,the results obtained from the evaluation of the sensitivity of the parameters are significant,in this way the hypothesis that is raised is approv

关键词： Sediments distributed model CASC2D-SED model

The Characteristics of Rainfall Runoff Pollution in North Moshui Lake Area

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The Characteristics of Rainfall Runoff Pollution in North Mo...