Hasil untuk "River, lake, and water-supply engineering (General)"

Menampilkan 16 dari ~9494229 hasil · dari DOAJ, Semantic Scholar, CrossRef

JSON API
DOAJ Open Access 2024
The productivity of selected soybean cultivars grown using various cultivation methods

Jerzy Księżak, Jolanta Bojarszczuk

Soybean is an important legume crop globally due to its rich protein, oil content, and functional components. The purpose of this study was to evaluate the yield of selected soybean cultivars depending on cultivation methods. The three-year field experiment, conducted from 2018 to 2020 at the Agricultural Experimental Station in Kępa-Puławy, Osiny farm (Institute of Soil Science and Plant Cultivation – State Research Institute in Puławy), investigated these variations. The first experimental factor was the soil cultivation method: A – conventional tillage, B – reduced tillage, and C – strip tillage. The second variable was soybean cultivar: ‘Aldana’ and ‘Merlin’. The soybean cultivars were selected for their differing maturity rates: ‘Aldana’ (000) is an early cultivar, while ‘Merlin’ (000++) semi-late cultivar. The field experiment utilised a split-plot design on Luvisol soil with sandy loam texture, belonging to a good rye complex, class IIIb–IVa, and was replicated four times. The study showed that the productivity (seed and protein yield) of the ‘Merlin’ cultivar grown in the central-eastern part of Poland was approximately 8% higher than that of the ‘Aldana’ cultivar. The cultivation method had a relatively minor influence on soybean yield, the content of selected nutrients, morphological features, and elements of the yield structure. The soil in strip-tillage method was more compact than the soil cultivated with a plough. After harvesting soybeans at a depth of 30, and 40 cm, the compactness of soil in strip-tillage or with reduced tillage was much lower than in spring, highlighting a positive effect of soybean cultivation on loosening the arable layer.

River, lake, and water-supply engineering (General), Irrigation engineering. Reclamation of wasteland. Drainage
DOAJ Open Access 2024
The Impact of Fallen Tree Trunks on the River Flow Path on the Characteristics of the Hyporheic Area Using Comsol Software (Case Study: Garmabdasht River, Gorgan)

mohsen barzali, mohsen Masoudian, ramin Fazloula et al.

Extended Abstract Background: Rivers are complex systems in which all kinds of chemical, biological, and physical processes take place and change under the influence of various factors and variables in terms of dimensions, shape, direction, and pattern. The changes that occur in the conditions of rivers have many effects on the river ecosystem. Carrying out any activity in rivers requires knowing the rules governing the river and predicting the river's reaction to it to avoid the related harmful consequences. It is usually difficult to understand the processes of rivers by measuring hydraulic parameters on a real scale. On the other hand, sediment transport modeling is also a very complex and difficult matter because the information that is used to predict bed changes is basically uncertain and the theories used are experimental and highly sensitive to a wide range of physical variables. The high costs of laboratory equipment and the limitation of using measuring devices are among the other reasons that limit the use of physical methods and lead experts to mathematical and numerical modeling to simulate the flow inside water channels. Continuous change is one of the governing principles of every river, and a change in flow conditions also causes changes and displacement in other geometric characteristics of the river. Because rivers are often moving in their alluvial beds, different types of bed forms have been formed in the river bed due to the shear stress in the bed. The formed shapes cause a part of the surface water flow in the river to enter the porous environment below it and return to the surface water flow after oxygenating and feeding benthic organisms. This type of currents that arise from the mixing of surface current and subsurface current in the porous environment under and around the river is called hyperic current. The surface, subsurface, and underground water systems and exchanges between them are in three levels: point, interval, and watershed. Fallen tree trunks are common structures in rivers. One of the factors in creating hyperic exchange is the presence of a pressure gradient at the border of surface flow and the porous medium. The pressure gradient is caused by various factors such as obstacles in the flow path or bed forms. Depending on the magnitude of these factors, they will affect the amount of exchange and the depth of the hyperic expansion. The first step in understanding the hyperic phenomenon and its application is to examine changes in the characteristics of this area, including the amount of current exchange, depth, and retention time. Therefore, the objectives of this research are to investigate the effect of natural obstacles created by tree trunks on hyperic characteristics and the effect of the arrangement of natural obstacles created by tree trunks on hyperic characteristics. Methods: The current field research was carried out in the Garambadesht River of Gorgan in the summer and winter of 2021 to investigate the effect of fallen tree trunks on the river path as a natural flow barrier in different tree trunk thicknesses (30, 60, and 90 cm). As one of the most important sources of drinking water for the city of Gorgan, the Garmabadesht River, originates from the slopes of Yazdaki Mountain at a point 27 km southeast of Gorgan and continues to flow northward. Then, it passes through the high and complex heights and enters the eastern plains of Gorgan. To carry out the present research, piezometers were installed in the upstream and downstream of the tree trunks and then evaluated using a numerical model in the Comsol software environment, compared to the simulation of the hyperic flow to estimate the amount of exchange flow. Results: This study obtained convincing findings regarding the correlation between piezometer observational data and numerical simulation results. A 91% correlation was obtained between piezometer observation data and simulation results, which was used as a basis to investigate the computational exchange flows from the numerical model. The findings showed that the amount of exchanged flow in blocked conditions was higher than in non-blocked conditions. This issue shows that tree trunks can have a significant impact on the dynamics of hyperic flow, an important consequence of which is the direct impact on river ecosystems, especially in relation to the preservation of coastal vegetation and aquatic habitats. The investigation of the retention time of the flow lines in three obstacle states shows that the increase of the obstacle in the flow path has increased the retention time because the flow lines have become deeper and their length has increased with the increase in the height of the obstacle, thereby increasing the retention time. Conclusion: The results indicate that the maximum amount of equilibrium discharge occurs in the case where the thickness of the tree trunk is 30 cm in winter. The amount of exchange flow with obstruction is higher than that without obstruction. The equilibrium flow rate in winter is higher than the exchange flow rate in summer. The investigation of the penetration of flow lines shows that the penetration rate of flow lines has increased with the increase in the thickness of the barrier. Considering the vastness of the research field, it is appropriate to conduct more research to discover more understanding of its mechanism.

River, lake, and water-supply engineering (General)
DOAJ Open Access 2023
Heavy metals content in the water of the rivers of the Central Caucasus (the Terek River basin)

Fatimat A. Atabieva, Asiyat S. Otarova

The identification of the hydrological and hydrochemical characteristics of the water of specific water bodies is of great importance in solving the problems of environmental regulation. For Russia, with its extreme diversity of natural and climatic conditions, this is especially important. Accordingly, during environmental regulation, it is necessary to take into account the regional peculiarities of the formation of the chemical composition of natural waters. The article presents data on the content of dissolved forms of heavy metals TM (V, Cr, Mn, Zn, Cd, Pb, Mo, Ni) in the water of the rivers of the Central Caucasus (Malka, Baksan, Cherek, Urukh, Terek, Nalchik, Lesken, Chegem, Shalushka, Urvan, Kurkuzhin) in the middle and lower the current. The security of river flow in 2021 was 50 %.The water resources of the Terek River basin play a key role in the economy of the republics. In terms of the degree of economic and environmental impact, the basin, which has great industrial, economic, health and recreational significance, is among the most strained.

River, lake, and water-supply engineering (General)
CrossRef Open Access 2022
Changes of Lake Area, Groundwater Level and Vegetation under the Influence of Ecological Water Conveyance—A Case Study of the Tail Lake of Tarim River in China

Xinfeng Zhao, Hailiang Xu, Peng Zhang

To study the changes of water and vegetation coverage, groundwater level and plant diversity of lakes at the end of Tarim River in Northwest China, the changes of various indicators in more than 20 years (2000–2019) were analyzed through field investigation and indoor remote sensing methods. The results showed that (1): with the initiation of the development of ecological water conveyance project, water and vegetation areas increased significantly, especially the trend of vegetation areas becoming more significant, and area of sandy land decreased significantly. (2): the plant diversity increased in the early stage of ecological water conveyance, however, with the increase of lake area and groundwater level, the species composition tends to be simplified. According to the variation characteristics of species importance value in the overflow area in recent 20 years, it is found that the top communities of plant succession are Phragmites australis and Hexinia polydichotoma. (3): with the increase in the lake area, the groundwater level showed an up-lifted trend, the correlation between the two was significant, but there was a lag in the response of the groundwater level. (4): The intra-annual variations in the lake areas were considerable before and after the ecological water conveyance.

DOAJ Open Access 2022
Assessment of meander‐bend migration of a major distributary of the Ganges River within Bangladesh

Jannatul Ferdoush, Subir Biswas, M. Shahjahan Mondal

Abstract The Arial Khan is an important distributary river of the Ganges River within Bangladesh. The river is meandering, and channel shifting and bend migration are common. This study investigates the bend‐scale morphology of 37 characteristic bends of the river using Landsat imageries, river bathymetries, and hydrological data. The morphological changes of the river are correlated with the temporal shifting of its offtake, which in turn is linked to the dynamic behavior of the river in terms of sinuosity, bend geometry, and bend migration. Alterations in the offtake location, bed elevation, and in‐front bar formation are found to control the flow to the river. The sinuosity varies from 1.62 to 1.95 and is linked to the shifting of its offtake. The lifetimes of the bends increase from upstream to downstream with an average lifetime of 24 years. The radii of the bends vary from upper to lower reaches with an average radius of 921 m. The upper reach is more migration prone, and its average migration rate (108 m/year) is more than twice the other two reaches. A higher migration rate of 70–80 m/year is found for the river during 1981–1999 compared to the rates of 45–50 m/year for the rest of the study periods (1972–2021). An envelope curve depicting the relation between the relative curvature of a bend and its migration rate for the river is also developed. The overall morphology from 1972 to 2021 indicates that a significant increase in sinuosity and a reduction in river width and aspect ratio have occurred. The migration rate has declined slightly and the frequency of bend cutoffs has reduced notably in recent years. Nonetheless, due to the high rates of migration, there exists potential future threat to riverbank erosion in some critical bends, and hence damages to land, property, structure, and project on the vulnerable banks.

Oceanography, River, lake, and water-supply engineering (General)
S2 Open Access 2022
KIZILÇAM MEŞCERESİNDE BAZI SU KALİTE PARAMETRELERİNİN YAĞIŞ DİSPOZİSYONUNDA YER ALAN BAZI ÖĞELERE GÖRE DEĞİŞİMİ

Bülent Abiz, Mahmut Reis

: Water is undoubtedly one of the most important consumable resources in maintaining a healthy life. Of the total amount of 1.4 billion km 3 in the world, 97.5% of the water is found in the oceans and seas as salt water, and 2.5% as fresh water in glaciers, underground, rivers and lakes. Of the 2.5% of fresh water resources, 68.6% are in glaciers, 30.1% are underground and the remaining 1.3% are in rivers, lakes and the atmosphere as surface water. Arid and semi-arid regions, which constitute 30% of the terrestrial areas, are the most distressed areas in terms of water resources. Due to global warming, the unconscious use of natural resources, and the increase in the population, the demand for water is decreasing and the quality of water decreases.In this study, which was carried out in Kahramanmaraş Sütçü İmam University Faculty of Forestry Başkonuş Research and Application Forest, it was determined how some elements in precipitation disposition (precipitation, throughfall, stem flow and surface runoff) showed a change on some water quality parameters in the red pine stand. For this purpose, mechanisms were established in the research area to collect water samples from rainwater, throughfall, stemflow runoff and surface runoff. In this study conducted in the Kahramanmaras Sutcu Imam University, Faculty of Forestry Baskonus Research and Application Forest, it was determined that some parameters precipitation (P), througfall (TF), stemflow (SF), and runoff (RO) and how these parameters change on some water quality parameters according to Turkish Pine stand. According to the data obtained, the average pH value was 6.66 in AA General, while the same value was determined as 6.23, 5.83 and 6.34 in OA Red Pine, GA Red Pine and YA Red Pine.. As a result of the measurements and statistical analyzes, significant differences were found between the rain water and the red pine stand. Particular attention should be paid not to replace the forested areas in the basins that supply water to the settlements with different land uses. Erosion and sedimentation from woodland cutting and transport should be minimized by careful planning.

CrossRef Open Access 2022
Seasonal variations of river and lake water surface areas at global scale

Patrice Carbonneau, Simone Bizzi

Abstract Much progress has been made over the last decade to build global inventories of freshwater resources. However, existing freshwater inventories are generally produced for a fixed period in time and/or do not discriminate lakes from rivers. The emergence of deep learning methods and Big Data platforms such as Google Earth Engine offers a potential solution. Here we present a unique raster dataset at 10 m spatial resolution which classifies freshwater into rivers and lakes for a study site covering 89% of the terrestrial landmass and for the months of April, July and October 2021. This data gives us the first global-scale direct count of lakes larger than 1 hectare as ~7.3 million. We also present the first intra-annual ranges for the areas distinctly occupied by rivers and lakes where we find that basins influenced by the Asian summer monsoon (e.g. the Ganges) closely followed by the Amazon display the largest intra-annual range of river area per unit basin area. Finally, we find that whilst maximum of lake water surface occurs in October 2021, the maximum river surface is in July 2021 leading us to conclude that the global maximum occurrences of river water and lake water are not synchronous.

S2 Open Access 2020
RETRACTED ARTICLE: Construction of community life circle database based on high-resolution remote sensing technology and multi-source data fusion

J. Zuo, L. Meng, Chen Li et al.

Statement of Retraction We, the Editor and Publisher of the journal European Journal of Remote Sensing, have retracted the following articles that were published in the Special Issue titled “Remote Sensing in Water Management and Hydrology”: Marimuthu Karuppiah, Xiong Li & Shehzad Ashraf Chaudhry (2021) Guest editorial of the special issue “remote sensing in water management and hydrology”, European Journal of Remote Sensing, 54:sup2, 1-5, DOI: 10.1080/22797254.2021.1892335 Jian Sheng, Shiyi Jiang, Cunzhu Li, Quanfeng Liu & Hongyan Zhang (2021) Fluid-induced high seismicity in Songliao Basin of China, European Journal of Remote Sensing, 54:sup2, 6-10, DOI: 10.1080/22797254.2020.1720525 Guohua Wang, Jun Tan & Lingui Wang (2021) Numerical simulation of temperature field and temperature stress of thermal jet for water measurement, European Journal of Remote Sensing, 54:sup2, 11-20, DOI: 10.1080/22797254.2020.1743956 Le Wang, Guancheng Jiang & Xianmin Zhang (2021) Modeling and molecular simulation of natural gas hydrate stabilizers, European Journal of Remote Sensing, 54:sup2, 21-32, DOI: 10.1080/22797254.2020.1738901 Tianyi Chen, Lu Bao, Liu Bao Zhu, Yu Tian, Qing Xu & Yuandong Hu (2021) The diversity of birds in typical urban lake-wetlands and its response to the landscape heterogeneity in the buffer zone based on GIS and field investigation in Daqing, China, European Journal of Remote Sensing, 54:sup2, 33-41, DOI: 10.1080/22797254.2020.1738902 Zhiyong Wang (2021) Research on desert water management and desert control, European Journal of Remote Sensing, 54:sup2, 42-54, DOI: 10.1080/22797254.2020.1736953 Ji-Tao Li & Yong-Quan Liang (2021) Research on mesoscale eddy-tracking algorithm of Kalman filtering under density clustering on time scale, European Journal of Remote Sensing, 54:sup2, 55-64, DOI: 10.1080/22797254.2020.1740894 Wei Wang, R. Dinesh Jackson Samuel & Ching-Hsien Hsu (2021) Prediction architecture of deep learning assisted short long term neural network for advanced traffic critical prediction system using remote sensing data, European Journal of Remote Sensing, 54:sup2, 65-76, DOI: 10.1080/22797254.2020.1755998 Yan Chen, Ming Tan, Jiahua Wan, Thomas Weise & Zhize Wu (2021) Effectiveness evaluation of the coupled LIDs from the watershed scale based on remote sensing image processing and SWMM simulation, European Journal of Remote Sensing, 54:sup2, 77-91, DOI: 10.1080/22797254.2020.1758962 Ke Deng & Ming Chen (2021) Blasting excavation and stability control technology for ultra-high steep rock slope of hydropower engineering in China: a review, European Journal of Remote Sensing, 54:sup2, 92-106, DOI: 10.1080/22797254.2020.1752811 Yufa He, Xiaoqiang Guo, Jun Liu, Hongliang Zhao, Guorong Wang & Zhao Shu (2021) Dynamic boundary of floating platform and its influence on the deepwater testing tube, European Journal of Remote Sensing, 54:sup2, 107-116, DOI: 10.1080/22797254.2020.1762246 Kai Peng, Yunfeng Zhang, Wenfeng Gao & Zhen Lu (2021) Evaluation of human activity intensity in geological environment problems of Ji’nan City, European Journal of Remote Sensing, 54:sup2, 117-121, DOI: 10.1080/22797254.2020.1771214 Wei Zhu, XiaoSi Su & Qiang Liu (2021) Analysis of the relationships between the thermophysical properties of rocks in the Dandong Area of China, European Journal of Remote Sensing, 54:sup2, 122-131, DOI: 10.1080/22797254.2020.1763205 Yu Liu, Wen Hu, Shanwei Wang & Lingyun Sun (2021) Eco-environmental effects of urban expansion in Xinjiang and the corresponding mechanisms, European Journal of Remote Sensing, 54:sup2, 132-144, DOI: 10.1080/22797254.2020.1803768 Peng Qin & Zhihui Zhang (2021) Evolution of wetland landscape disturbance in Jiaozhou Gulf between 1973 and 2018 based on remote sensing, European Journal of Remote Sensing, 54:sup2, 145-154, DOI: 10.1080/22797254.2020.1758963 Mingyi Jin & Hongyan Zhang (2021) Investigating urban land dynamic change and its spatial determinants in Harbin city, China, European Journal of Remote Sensing, 54:sup2, 155-166, DOI: 10.1080/22797254.2020.1758964 Balaji L. & Muthukannan M. (2021) Investigation into valuation of land using remote sensing and GIS in Madurai, Tamilnadu, India, European Journal of Remote Sensing, 54:sup2, 167-175, DOI: 10.1080/22797254.2020.1772118 Xiaoyan Shi, Jianghui Song, Haijiang Wang & Xin Lv (2021) Monitoring soil salinization in Manas River Basin, Northwestern China based on multi-spectral index group, European Journal of Remote Sensing, 54:sup2, 176-188, DOI: 10.1080/22797254.2020.1762247 GN Vivekananda, R Swathi & AVLN Sujith (2021) Multi-temporal image analysis for LULC classification and change detection, European Journal of Remote Sensing, 54:sup2, 189-199, DOI: 10.1080/22797254.2020.1771215 Yiting Wang, Xianghui Liu & Weijie Hu (2021) The research on landscape restoration design of watercourse in mountainous city based on comprehensive management of water environment, European Journal of Remote Sensing, 54:sup2, 200-210, DOI: 10.1080/22797254.2020.1763206 Bao Qian, Cong Tang, Yu Yang & Xiao Xiao (2021) Pollution characteristics and risk assessment of heavy metals in the surface sediments of Dongting Lake water system during normal water period, European Journal of Remote Sensing, 54:sup2, 211-221, DOI: 10.1080/22797254.2020.1763207 Jin Zuo, Lei Meng, Chen Li, Heng Zhang, Yun Zeng & Jing Dong (2021) Construction of community life circle database based on high-resolution remote sensing technology and multi-source data fusion, European Journal of Remote Sensing, 54:sup2, 222-237, DOI: 10.1080/22797254.2020.1763208 Zilong Wang, Lu Yang, Ping Cheng, Youyi Yu, Zhigang Zhang & Hong Li (2021) Adsorption, degradation and leaching migration characteristics of chlorothalonil in different soils, European Journal of Remote Sensing, 54:sup2, 238-247, DOI: 10.1080/22797254.2020.1771216 R. Vijaya Geetha & S. Kalaivani (2021) A feature based change detection approach using multi-scale orientation for multi-temporal SAR images, European Journal of Remote Sensing, 54:sup2, 248-264, DOI: 10.1080/22797254.2020.1759457 LianJun Chen, BalaAnand Muthu & Sivaparthipan cb (2021) Estimating snow depth Inversion Model Assisted Vector Analysis based on temperature brightness for North Xinjiang region of China, European Journal of Remote Sensing, 54:sup2, 265-274, DOI: 10.1080/22797254.2020.1771217 Yajuan Zhang, Cuixia Li & Shuai Yao (2021) Spatiotemporal evolution characteristics of China’s cold chain logistics resources and agricultural product using remote sensing perspective, European Journal of Remote Sensing, 54:sup2, 275-283, DOI: 10.1080/22797254.2020.1765202 Guangping Liu, Jingmei Wei, BalaAnand Muthu & R. Dinesh Jackson Samuel (2021) Chlorophyll-a concentration in the hailing bay using remote sensing assisted sparse statistical modelling, European Journal of Remote Sensing, 54:sup2, 284-295, DOI: 10.1080/22797254.2020.1771774 Yishu Qiu, Zhenmin Zhu, Heping Huang & Zhenhua Bing (2021) Study on the evolution of B&Bs spatial distribution based on exploratory spatial data analysis (ESDA) and its influencing factors—with Yangtze River Delta as an example, European Journal of Remote Sensing, 54:sup2, 296-308, DOI: 10.1080/22797254.2020.1785950 Liang Li & Kangning Xiong (2021) Study on peak cluster-depression rocky desertification landscape evolution and human activity-influence in South of China, European Journal of Remote Sensing, 54:sup2, 309-317, DOI: 10.1080/22797254.2020.1777588 Juan Xu, Mengsheng Yang, Chaoping Hou, Ziliang Lu & Dan Liu (2021) Distribution of rural tourism development in geographical space: a case study of 323 traditional villages in Shaanxi, China, European Journal of Remote Sensing, 54:sup2, 318-333, DOI: 10.1080/22797254.2020.1788993 Lin Guo, Xiaojing Guo, Binghua Wu, Po Yang, Yafei Kou, Na Li & Hui Tang (2021) Geo-environmental suitability assessment for tunnel in sub-deep layer in Zhengzhou, European Journal of Remote Sensing, 54:sup2, 334-340, DOI: 10.1080/22797254.2020.1788994 Hui Zhou, Cheng Zhu, Li Wu, Chaogui Zheng, Xiaoling Sun, Qingchun Guo & Shuguang Lu (2021) Organic carbon isotope record since the Late Glacial period from peat in the North Bank of the Yangtze River, China, European Journal of Remote Sensing, 54:sup2, 341-347, DOI: 10.1080/22797254.2020.1795728 Chengyuan Hao, Linlin Song & Wei Zhao (2021) HYSPLIT-based demarcation of regions affected by water vapors from the South China Sea and the Bay of Bengal, European Journal of Remote Sensing, 54:sup2, 348-355, DOI: 10.1080/22797254.2020.1795730 Wei Chong, Zhang Lin-Jing, Wu Qing, Cao Lian-Hai, Zhang Lu, Yao Lun-Guang, Zhu Yun-Xian & Yang Feng (2021) Estimation of landscape pattern change on stream flow using SWAT-VRR, European Journal of Remote Sensing, 54:sup2, 356-362, DOI: 10.1080/22797254.2020.1790994 Kepeng Feng & Juncang Tian (2021) Forecasting reference evapotranspiration using data mining and limited climatic data, European Journal of Remote Sensing, 54:sup2, 363-371, DOI: 10.1080/22797254.2020.1801355 Kepeng Feng, Yang Hong, Juncang Tian, Xiangyu Luo, Guoqiang Tang & Guangyuan Kan (2021) Evaluating applicability of multi-source precipitation datasets for runoff simulation of small watersheds: a case study in the United States, European Journal of Remote Sensing, 54:sup2, 372-382, DOI: 10.1080/22797254.2020.1819169 Xiaowei Xu, Yinrong Chen, Junfeng Zhang, Yu Chen, Prathik Anandhan & Adhiyaman Manickam (2021) A novel approach for scene classification from remote sensing images using deep learning methods, European Journal of Remote Sensing, 54:sup2, 383-395, DOI: 10.1080/22797254.2020.1790995 Shanshan Hu, Zhaogang Fu, R. Dinesh Jackson Samuel & Prathik Anandhan (2021) Application of active remote sensing in confirmation rights and identification of mortgage supply-demand subjects of rural land in Guangdong Province, European Journal of Remote Sensing, 54:sup2, 396-404, DOI: 10.1080/22797254.2020.1790996 Chen Qiwei, Xiong Kangning & Zhao Rong (2021)

10 sitasi en Computer Science
DOAJ Open Access 2020
Entropy weight method coupled with an improved DRASTIC model to evaluate the special vulnerability of groundwater in Songnen Plain, Northeastern China

Bin Wang, Yanguo Teng, Huiqun Wang et al.

The Songnen Plain in Northeast China is the only remaining black soil agricultural area in the world and is an important food base for China. The groundwater resources in this area are abundant, but human activities have caused them polluted. This paper established a groundwater vulnerability assessment to characterize the influence of human activities which used an entropy weight method. The index was tested using the nitrate pollution distribution in the groundwater to verify the effectiveness of this method. The results showed that areas with high specific vulnerability were distributed in the northern and eastern parts of the Songnen Plain and were consistent with areas that showed serious nitrate pollution of the groundwater. The correlation coefficient between these areas was 0.2536, which greatly improved the vulnerability assessment without superimposing human activities in the model. The results clearly showed that human activities increased groundwater vulnerability on the Songnen Plain. The evaluation method provided a reference for similar evaluations and a basis for the protection and management of groundwater resources in this region. HIGHLIGHTS Establishing a groundwater vulnerability assessment method to characterize the influence of human activities using an entropy weight method.; Entropy weight method coupled with an improved DRASTIC model to evaluate the special vulnerability of groundwater for water management.;

River, lake, and water-supply engineering (General), Physical geography
DOAJ Open Access 2019
A 3D analytical model for vortex velocity field based on spiral streamline pattern

Maryam Azarpira, Amir Reza Zarrati

Vortices that develop over intakes are a hazardous hydraulic phenomenon. In this study, a 3D model was developed to study the flow field in air-core vortices. This model is based on the spiral pattern of streamlines and the analytical solution of the momentum and continuity equations for deriving the three components of velocity. The model provides equations for free surface profiles and 3D patterns of the streamlines. Moreover, a new relationship was suggested for calculating effective viscosity and its distribution across the vortex flow field. The performance of the proposed analytical model was compared with existing experimental data and the results of previous analytical models. The outcomes indicated that the proposed model could predict characteristics of the vortex flow with good accuracy. Keywords: Air-core vortices, Analytical model, Velocity distribution, Spiral streamlines, Free surface profile

River, lake, and water-supply engineering (General)
DOAJ Open Access 2013
Study of heat treatment parameters for large-scale hydraulic steel gate track

Ping-zhou Cao, Guang-zhong Liu, Kai Wu

In order to enhance external hardness and strength, a large-scale hydraulic gate track should go through heat treatment. The current design method of hydraulic gate wheels and tracks is based on Hertz contact linear elastic theory, and does not take into account the changes in mechanical properties of materials caused by heat treatment. In this study, the heat treatment parameters were designed and analyzed according to the bearing mechanisms of the wheel and track. The quenching process of the track was simulated by the ANSYS program, and the temperature variation, residual stress, and deformation were obtained and analyzed. The metallurgical structure field after heat treatment was predicted by the method based on time-temperature-transformation (TTT) curves. The results show that the analysis method and designed track heat treatment process are feasible, and can provide a reference for practical projects.

River, lake, and water-supply engineering (General)

Halaman 27 dari 474712