Journal articles on the topic 'Areal infiltration'
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1
Gray, D. M., Brenda Toth, Litong Zhao, J. W. Pomeroy, and R. J. Granger. "Estimating areal snowmelt infiltration into frozen soils." Hydrological Processes 15, no. 16 (2001): 3095–111. http://dx.doi.org/10.1002/hyp.320.
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Moss, AJ, and CL Watson. "Rain impact soil crust. III. Effects of continuous and flawed crusts on infiltration, and the ability of plant covers to maintain crustal flaws." Soil Research 29, no. 2 (1991): 311. http://dx.doi.org/10.1071/sr9910311.
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Experiments on unsteady infiltration, through rain-impact soil crusts on an albaqualf, employed 70 mm diameter cylinders surrounded by airsplash-exchange areas. Significant throttling effects resulted. Circular, fabricated flaws of varying diameter caused strong bypassing of the crust by infiltrating water. As the percentage of total area flawed rose from 1% to 10%, infiltration rates rose from near those of fully-crusted values to those of uncrusted values, further areal increases bringing little change. This result suggested three-dimensional water movement beneath flaws. Sheltering by plant covers produced flaws in the rain-impact soil crust. However, sheltered areas often acted as traps for incoming, finely comminuted, airsplash debris which, once deposited, could also throttle infiltration. Moreover, the compacted layer, the main throttling agent of the rain-impact soil crust, often extended laterally into sheltered areas. Wheat-straw stems, less than a drop diameter apart, were effective flaw preservers, even under heavy airsplash, inhibiting formation of the compacted layer and stimulating removal of airsplash deposits. Grass covers, dense enough to intercept all raindrops, were also highly effective against infiltration throttling because intercepted raindrops were converted, via the double-edge effect, into non-erosive, fine, impact droplets which could not disturb the soil.
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Govindaraju, Rao S., R. Morbidelli, and C. Corradini. "Areal Infiltration Modeling over Soils with Spatially Correlated Hydraulic Conductivities." Journal of Hydrologic Engineering 6, no. 2 (April 2001): 150–58. http://dx.doi.org/10.1061/(asce)1084-0699(2001)6:2(150).
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Corradini, Corrado, Rao S. Govindaraju, and Renato Morbidelli. "Simplified modelling of areal average infiltration at the hillslope scale." Hydrological Processes 16, no. 9 (2002): 1757–70. http://dx.doi.org/10.1002/hyp.394.
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Bejo Slamet, Dewi Sagita Ginting, and Deni Elfiati. "Pemanfaatan Data Sifat Tanah Dalam Pendugaan Laju Infiltrasi Pada Areal Hutan Berlereng Curam." Talenta Conference Series: Agricultural and Natural Resources (ANR) 2, no. 1 (July 25, 2019): 65–70. http://dx.doi.org/10.32734/anr.v2i1.575.
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Kendala pengukuran infiltrasi pada lahan hutan pegunungan adalah posisi lokasi yang jauh dan mempunyai kelerengan yang curam sampai sangat curam. Penelitian ini dilakukan untuk mendapatkan model hubungan antara sifat tanah pada areal hutan yang berlereng curam dengan laju infiltrasi. Penelitian dilakukan di Taman Hutan Raya (Tahura) Bukit Barisan Kabupaten Karo Provinsi Sumatera Utara. Sifat tanah yang dijadikan sebagai parameter penduga adalah tekstur tanah, bulk density (kepadatan tanah) dan bahan organik. Pengukuran infiltrasi di lapangan dilakukan dengan metode double ring infiltrometer. Hasil penelitian menunjukkan bahwa fraksi liat, bulk density, porositas dan bahan organic mampu memberikan nilai pendugaan laju infiltrasi maksimum dengan koefisien determinasi (R2) sebesar 0,567 dan pendugaan waktu mencapai konstan dengan koefisien determinasi (R2) sebesar 0,760. Adapaun model persamaan penduga laju infiltrasi minimum hanya memberikan nilai koefisien determinasi sebesar 0,162. Variabilitas spasial laju infiltrasi yang tinggi mengakibatkan pendugaan menggunakan sifat fisik tanah masih memberikan koefisisen determinasi yang rendah. Namun demikian model persamaan ini dapat dijadikan sebagai penduga infiltrasi pada areal pebukitan dengan kelerengan curam dan jauh dari sumber air.
The constraints on measuring infiltration on mountain forest land are the remote locations and have steep slopes to very steep. This research was conducted to obtain a model of the relationship between the soil properties in steep slope forests with infiltration rates. The study was held in the Bukit Barisan Forest Park (Tahura), Karo Regency, North Sumatra Province. The properties of the soil which are used as estimating parameters are soil texture, bulk density and soil organic matter. Measurement of infiltration in the field was done by t double ring infiltrometer method. The results show that the clay fraction, bulk density, porosity and soil organic matter were able to provide the estimation values of maximum infiltration rate with a coefficient of determination (R2) of 0.567 and the estimation of constant time with a coefficient of determination (R2) of 0.760. However, the estimation equation of minimum infiltration rate model only gives a determination coefficient of 0.162. The high spatial variability of infiltration rate in the field resulting in the low of the coefficient of determination of the model. However, this equation model can be used as an estimator of infiltration in hills with steep slopes and far from water sources.
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Carter, Rachel, Benjamin Davis, Landon Oakes, Matthew R. Maschmann, and Cary L. Pint. "A high areal capacity lithium–sulfur battery cathode prepared by site-selective vapor infiltration of hierarchical carbon nanotube arrays." Nanoscale 9, no. 39 (2017): 15018–26. http://dx.doi.org/10.1039/c7nr02368e.
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Sharma, M. L., R. J. W. Barron, and M. S. Fernie. "Areal distribution of infiltration parameters and some soil physical properties in lateritic catchments." Journal of Hydrology 94, no. 1-2 (October 1987): 109–27. http://dx.doi.org/10.1016/0022-1694(87)90035-7.
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Assouline, S., and Y. Mualem. "Infiltration during soil sealing: The effect of areal heterogeneity of soil hydraulic properties." Water Resources Research 38, no. 12 (December 2002): 22–1. http://dx.doi.org/10.1029/2001wr001168.
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Porter, Quinton, Xiaochun Li, and Chao Ma. "Pressing and Infiltration of Metal Matrix Nanocomposites." Journal of Manufacturing and Materials Processing 5, no. 2 (May 28, 2021): 54. http://dx.doi.org/10.3390/jmmp5020054.
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The ability to produce metal matrix nanocomposites via pressing and infiltration was validated. Al/TiC nanocomposite was used as the model material. Pressing the powder in a die yielded cylindrical specimens with a green density of 1.98 ± 0.05 g/cm3, which was increased to only 2.11 ± 0.12 g/cm3 by sintering. Direct infiltration of the pressed specimens at 1050 °C for 3.5 h yielded specimens with a density of 3.07 ± 0.08 g/cm3, an open porosity of 3.06 ± 1.40%, and an areal void fraction of 8.09 ± 2.67%. The TiC nanoparticles were verified to be well dispersed using energy-dispersive X-ray spectroscopy. The measured hardness of 64 ± 3 HRA makes it a promising material for structural applications in industries such as aerospace and automotive.
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Holko, L., Z. Kostka, and M. Šanda. "Assessment of frequency and areal extent of overland flow generation in a forested mountain catchment." Soil and Water Research 6, No. 1 (March 1, 2011): 43–53. http://dx.doi.org/10.17221/33/2010-swr.
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Short time rainfall and throughfall measurements in the period May–October 2009, and the calculated saturated hydraulic conductivities of soils and isotopic hydrograph separations in August 2009 were used to estimate the frequency of the infiltration excess overland flow generation and the extent of saturated areas producing the saturation excess overland flow in the forested mountain catchment of the Jalovecký Creek, Western Tatra Mountains, northern Slovakia. The rainfall intensities exceeding 0.2 mm per 10 min occurred only in 2–4% of all data measured. Saturated hydraulic conductivities (K<sub>S</sub>) of soils were calculated by means of four methods based on the relationship between K<sub>S</sub> and soil texture. The comparison of K<sub>S</sub> with the measured rainfall intensities indicated that the infiltration excess overland flow could have been generated for 0–10% of the rainfall intensities measured. Isotopic hydrograph separation by means of the deuterium isotope indicated that the areas, where the saturated excess overland flow could have occurred, represented about 2–13% of the catchment during the analysed events. Despite the uncertainties connected with the assessments, the results are consistent with empirical knowledge of the catchment and limited older data.
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Merz, Bruno, András Bárdossy, and Gerd R. Schiffler. "Different methods for modelling the areal infiltration of a grass field under heavy precipitation." Hydrological Processes 16, no. 7 (January 11, 2002): 1383–402. http://dx.doi.org/10.1002/hyp.347.
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Lloréns, Mercedes, Ana Belén Pérez-Marín, María Isabel Aguilar, Juan Francisco Ortuño, and Víctor Francisco Meseguer. "Oxygen Consumption in Two Subsurface Wastewater Infiltration Systems under Continuous Operation Mode." Water 12, no. 11 (October 26, 2020): 3007. http://dx.doi.org/10.3390/w12113007.
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In this work, an innovative arrangement of a vertical subsurface flow wastewater infiltration system (SWIS) was studied. The principal objective of this study was to evaluate the oxygen transfer rate (OTR) in two different pilot-scale arrangements of an SWIS. The two pilot plants were composed of four filter beds in series, one with a vertical arrangement of the beds (one over the other) and the other with a horizontal arrangement of the beds (one next to the other). Furthermore, two kinetic models were applied for correlating the COD and NH4+-N concentrations at the inlet and outlet of each treatment step in both pilot plants. The fitting of experimental data to the models allowed the calculation of the areal rate constants. The OTR values obtained were 54.69 g m−2 h−1 and 28.84 g m−2 h−1 for horizontal and vertical arrangement, respectively. These values were considerably higher than those obtained by other authors. The plug flow model describes the behaviour of these SWISs better, and the best fits were achieved for the vertical arrangement. The areal rate constant values obtained in this study were higher than those reported in the bibliography, which indicates a great removal efficiency and therefore lower surface area needed for the treatment.
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Pratiwi, Yesi Eka, Syarifuddin Kadir, and Badaruddin Badaruddin. "ANALISIS INFILTRASI PADA BERBAGAI TUTUPAN LAHAN DI SUB DAS BATI-BATI DAS MALUKA KALIMANTAN SELATAN." Jurnal Sylva Scienteae 4, no. 5 (October 25, 2021): 928. http://dx.doi.org/10.20527/jss.v4i5.4217.
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Land cover can affect the physical properties of soil related to the pace, volume and capacity of infiltration on a land. The purpose of this research is to know the pace of infiltration and to analyze the large capacity and volume of infiltration on several different land cover in Sub DAS Bati-Bati DAS Maluka. Data collection required is primary data and secondary data. The research method is purposive sampling means the retrieval of infiltration data, laying of infiltrometer tools and soil sampling with the ring samples in the area that can be considered to represent all areas research. The pace of infiltration will be faster on land cover which is overgrown by vegetation such as plantation than only land cover of reeds and shrub. The highest infiltration pace is at a plantation of 84.86 mm, while the lowest in the reeds land cover is 74.67 mm. The infiltration pace is influenced by the physical properties of the soil, when the physical properties of the soil will also increase the infiltration pace. The infiltration capacity is directly proportional to the volume of infiltration, the highest value is on the land cover of the shrub with an average infiltration capacity of 198.1 mm/hr and volume infiltration 125.17 mm3. Lowest value in reeds land cover with average infiltration capacity of 157.58 mm/hr and volume infiltration 114.69 mm3. At Plantation land cover the average value of infiltration capacity is 185.88 mm/hr and the volume of infiltration is 121.58 mm3Tutupan lahan dapat memberikan pengaruh terhadap sifat fisik tanah yang berhubungan dengan laju, kapasitas dan volume infiltrasi pada suatu lahan. Tujuan dari penelitian ini ialah untuk mengetahui laju infiltrasi serta menganalisis besar volume dan kapasitas infiltrasi pada beberapa tutupan lahan yang berbeda di Sub DAS Bati-Bati DAS Maluka. Pengumpulan data yang diperlukan ialah data primer dan data sekunder. Metode penelitian dilakukan secara purposive sampling artinya pengambilan data infiltrasi, peletakan alat infiltrometer dan pengambilan sampel tanah dengan ring sample diarea yang dianggap dapat mewakili seluruh areal yang diteliti. Laju infiltrasi akan semakin cepat pada tutupan lahan yang banyak ditumbuhi oleh vegetasi seperti perkebunan daripada hanya tutupan lahan alang-alang dan semak belukar. Laju infiltrasi paling tinggi ialah pada perkebunan sebesar 84,86 mm, sedangkan paling rendah pada tutupan lahan alang-alang sebesar 74,67 mm. Laju infiltrasi dipengaruhi oleh sifat fisik tanah, saat sifat fisik tanah bagus maka laju infiltrasi juga semakin meningkat. Kapasitas infiltrasi berbanding lurus dengan volume infiltrasi, nilai tertinggi ialah pada tutupan lahan semak belukar dengan rata-rata kapasitas infiltrasi 198,1 mm/jam dan volume infiltrasi 125,17 mm3. Nilai terendah pada tutupan lahan alang-alang dengan rata-rata kapasitas infiltrasi 157,58 mm/jam dan volume infiltrasi 114,69 mm3. Pada tutupan lahan perkebunan nilai rata-rata kapasitas infiltrasi ialah 185,88 mm/jam dan volume infiltrasi sebesar 121,58 mm3.
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Chitta, Maepadeapati, Syarifuddin Kadir, and Khairun Nisa. "ANALISIS INFILTRASI DI HUTAN KOTA PERKANTORAN GUBERNUR PROVINSI KALIMANTAN SELATAN." Jurnal Sylva Scienteae 4, no. 4 (August 27, 2021): 599. http://dx.doi.org/10.20527/jss.v4i4.3934.
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Urban forest is an important factor affecting the sustainability of ecological and social conditions in the urban environment. One of the urban forest in Banjarbaru is Tropical Rain Forest Miniature. The urban forest is located in the South Kalimantan provincial government office area in Banjarbaru. Development of the urban forest is a real act of the Government of South Kalimantan Province in the framework of reducing the rate of degradation of forest areas, especially areas that are downstream of the watershed. At different land uses will be found the type of vegetation and land management of different levels. Where these two things will also cause a different rate of infiltration. This research uses the Horton Model which aims to analyze the nature of the soil, determine the infiltration rate, infiltration capacity and infiltration volume in urban forest governor office of South Kalimantan province. Infiltration rate measurements using an infiltrometer conducted on 4 planting blocks in miniature tropical rainforest. The results showed that: 1) Texture of sandy clay loam and sandy loam; 2) The largest infiltration rate is in Block 4 with a value of 87.33 mm / hour and the lowest infiltration rate in Block 3 with a value of 29.00 mm / hour; 3) The largest infiltration capacity and infiltration volume are in Block 4, which is 46.23 mm / hour and 50.23 mm3, while the lowest infiltration capacity and infiltration volume is in Block 3, which is 12.82 mm / hour and 9.48 mm3Hutan kota merupakan faktor penting yang berpengaruh terhadap keberlanjutan kondisi ekologi dan sosial di lingkungan perkotaan. Salah satu hutan kota yang ada di Banjarbaru adalah Miniatur Hutan Hujan Tropis. Hutan Kota ini berada di areal kawasan perkantoran pemerintah provinsi Kalimantan Selatan di Banjarbaru. Pembangunan hutan kota merupakan tindakan nyata Pemerintah Provinsi Kalimantan Selatan dalam Rangka mengurangi laju degradasi hutan dan lahan, terutama daerah yang berada dihilir DAS. Pada tata guna lahan yang berbeda akan dijumpai jenis vegetasi dan tingkat pengolahan lahan yang berbeda. Dimana kedua hal tersebut juga akan menyebabkan terjadinya laju infiltrasi yang berbeda. Penelitian ini menggunakan Model Horton yang bertujuan untuk menganalisis sifat fisik tanah, menentukan besarnya laju infiltrasi, menentukan kapasitas infiltrasi dan volume infiltrasi di Hutan Kota Perkantoran Gubernur Provinsi Kalimantan Selatan. Pengukuran laju infiltrasi menggunakan infiltrometer yang dilakukan pada 4 blok tanam di miniatur hutan hujan tropis. Hasil penelitian diperoleh bahwa: 1) Tekstur tanah lempung liat berpasir dan lempung berpasir; 2) Besarnya laju infiltrasi terbesar terdapat pada Blok 4 dengan nilai 87,33 mm/jam dan laju infiltrasi terendah pada Blok 3 dengan nilai 29,00 mm/jam; 3) Kapasitas infiltrasi dan volume infiltrasi terbesar terdapat pada Blok 4 yaitu 46,23 mm/jam dan 50,23 mm3, sedangkan kapasitas infiltrasi dan volume infiltrasi terendah terdapat pada Blok 3 yaitu 12,82 mm/jam dan 9,48 mm3
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Govindaraju, Rao S., Corrado Corradini, and Renato Morbidelli. "A semi-analytical model of expected areal-average infiltration under spatial heterogeneity of rainfall and soil saturated hydraulic conductivity." Journal of Hydrology 316, no. 1-4 (January 2006): 184–94. http://dx.doi.org/10.1016/j.jhydrol.2005.04.019.
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Woldemariyam Tesema, Fethangest, Gebrerufael Hailu Kahsay, and Berihu Abadi Berhe. "Quantitative Geomorphological Parameters Analysis for the Aynalem- Illala Streams, Tigray, Northern Ethiopia." Momona Ethiopian Journal of Science 13, no. 1 (August 15, 2021): 67–88. http://dx.doi.org/10.4314/mejs.v13i1.4.
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Morphometric analysis is the measurement and mathematical analysis of the configuration of the surface, shape, and dimension of landforms. The objective of this study is to characterize the Aynalem and Illala streams using the morphometric parameter. The topographic map at a scale of 1:50,000 taken from the Ethiopian National Mapping Agency was used to characterize the linear and areal aspects. ASTER Digital Elevation Model with 10m resolution was used to characterize the relief aspect. The Arc GIS 10.4.1 was used during the morphometric analysis. The analysis result of the streams is summarized based on the linear, areal, and relief aspects. The area is characterized by a dendritic drainage pattern which is characteristics of massive hard rock terrain. The Aynalem and Illala streams are 4th and 5th order streams. Considering the number of streams in the Aynalem (75.81%) and Illala (74.66%) is composed of first-order streams that indicate a flashy flood and the mean bifurcation value of Aynalem (6.8) and Illala (4.7) shows that the Aynalem area is more structurally affected than Illala but both show less stream integration. The analysis of areal aspects such as elongation ratio, circularity ratio, and form factor has indicated that both streams are characterized as elongated streams, this implies that both streams are flowing in heterogeneous rock material, presences of structural effect, and slow runoff discharge. The other areal aspect such as drainage density, stream frequency, infiltration number, and length of overland flow all show smaller values in both streams. This implies that the streams are characterized by a relatively permeable rock material with a higher infiltration capacity. The relief aspect of the Aynalem and Illala was also analyzed using basin relief, relief ratio, ruggedness number, hypsometric curves, and Hypsometric integral. The streams are characterized by a lower relief ratio and ruggedness number which implies a relatively flat slope and lower relief. The hypsometric curves and the Hypsometric Integral of the streams indicate that the Aynalem and Illala are at the maturity stage. This shows the area is characterized by higher erosion but less affected by recent structures. Based on the morphometric parameter analysis result it is possible to conclude that the stream development is dependent on the topography and geology of the study area and both streams show similar morphometric character.
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Silva, Marcos Cleve Alves da, Marcelo Dos Santos Targa, and Vicente Rodolfo Santos Cezar. "Arduino system and ultrasonic sensor for automation of the determination of water infiltration rate in soil." Ambiente e Agua - An Interdisciplinary Journal of Applied Science 15, no. 7 (December 7, 2020): 1. http://dx.doi.org/10.4136/ambi-agua.2543.
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The velocity of water infiltration in soil is important for the design of irrigation systems, drainage, septic tanks, sanitary landfills, dams, channels for water distribution, soil and water management to control erosion and estimate surface runoff. Infiltration tests are generally done with rulers and visual reading, which can lead to errors. The present study therefore aimed to determine the Infiltration Velocity (IV) curves of water in the soil by the concentric ring infiltrometer method, using an Arduino microcontroller and an ultrasonic sensor to measure the lowering of the water depth. For that, in the same infiltration test, four readings in Automatic mode (AT) and four readings in Manual mode (MN) were performed simultaneously, in a red-yellow Argisol type soil, in the Areal Basin, located in the southeastern region of Brazil. municipality of Taubaté, Vale do Paraíba, in the state of São Paulo. Adjustments of kostiakov curves and their equations were made from the data obtained in the field, and the values of R² were determined, as well as the values of Basic Infiltration Velocities (BIV), Accumulated Infiltration (AI) and the Average Percentage Error (APE) of the calculated IS values and those estimated by the equations. The results show that the number of readings in the same test time in Automatic mode (AT) was 2.3 times higher than in the manual (MN). All tests showed that the Red-Yellow Argisol showed a high infiltration speed, and in the pasture area the BIV values were 1.9 times higher than those obtained in the forest area. The R² determination coefficients for all curves are 0.99 in all tests and demonstrate the strong correlation between the data. The APE of the calculated and estimated IS values were low, and the biggest discrepancies that occurred were (APE = 0.30%) in the MN - 4 test and (APE = -0.01%) in the AT - 4. APE of MN mode BIVs for AT was 2.7%. These differences in IS values are reflected in the accumulated infiltration (AI) in the soil over time, and in this study the AI of the ATs tests was on average 4.1mm higher than in the MN tests, which corresponds to a difference of 41m³ ha-1. It was concluded that the use of the Arduino microcontroller with the ultrasonic sensor installed in the ring infiltrometer proved to be efficient in the field measurements and made the determination of the accumulated infiltration and the infiltration speed practical, proving to be an economical and technically viable alternative mainly due to the quantity of possible points to collect for each test and the greater reliability added to the low error values when compared to the manual.
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Ariesta, Diana. "The Effect of Initial Groundwater Table and Rainfall Wetting Towards Slope Stability (Case Study of Landslide in Tangkil Hamlet, Banaran Village, Pulung Subdistrict, Ponorogo Regency)." Journal of the Civil Engineering Forum 5, no. 2 (May 17, 2019): 149. http://dx.doi.org/10.22146/jcef.43804.
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Landslide is a natural phenomenon that can be controlled by a combination of various factors, such as topography, lithological condition, geological structure, water table, etc. Landslide is stated as a natural disaster if it causes casualties, direct losses and subsequent impacts of the initial destruction, as happened in Banaran Village, Ponorogo Regency. This study is aimed to examine the effects of initial groundwater table conditions and rainfall wetting on Banaran Village landslide. This study was conducted by assuming scenarios of initial groundwater table conditions. Soil parameters were obtained by testing soil samples in the laboratory. Infiltration parameters were acquired through permeability tests using the Philip-Dunne method, while areal rainfall was calculated using the Thiessen polygon method. In addition, slope stability modeling was calculated by using SLOPE/W while rainfall wetting analysis was carried out through SEEP/W. The analysis of Banaran Village landslide through these two numerical models was conducted by considering two conditions: 1) without rainfall and 2) with rainfall and infiltration. The analysis results imply that the landslide occurred in the initial groundwater table condition in scenario 3 with a safety factor of 1.008, and in a similar scenario with a safety factor of 0.973 when taking into account rainfall and infiltration. The results from SEEP/W and SLOPE/W indicate that the initial condition of the groundwater table highly influenced the decrease of the safety factor, while the wetting process did not cause a significant decrease of the safety factor.
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Eames, I., I. Small, A. Frampton, and A. M. Cottenden. "Experimental and theoretical study of the spread of fluid from a point source on an inclined incontinence bed-pad." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 217, no. 4 (April 1, 2003): 263–71. http://dx.doi.org/10.1243/095441103322060712.
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The spread of fluid from a localized source on to a flat fibrous sheet is studied. The sheet is inclined at an angle, α, to the horizontal, and the areal flux of the fluid released is Qa. A new experimental study is described where the dimensions of the wetted region are measured as a function of time t, Qa and α (>0). The down-slope length, Y, grows according to Y ∼ ( Qa t)2/3(sin α)1/3; for high discharge rates and low angles of inclination, the cross-slope width, X, grows as ∼ ( Qa t)1/2, while for low discharge rates or high angles of inclination, the cross-slope transport is dominated by infiltration and X ∼ 2(2 KsΦ∗ t)1/2, where Ks is the saturated permeability and Φ∗ is the characteristic value of capillary pressure. A scaling analysis of the underlying non-linear advection diffusion equation describing the infiltration process confirms many of the salient features of the flow observed. Good agreement is observed between the collapse of the numerical solutions and experimental results. The broader implications of these results for incontinence bed-pad research are briefly discussed.
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Salvador, N., J. P. Monteiro, R. Hugman, T. Y. Stigter, and E. Reis. "Quantifying and modelling the contribution of streams that recharge the Querença-Silves aquifer in the south of Portugal." Natural Hazards and Earth System Sciences 12, no. 11 (November 6, 2012): 3217–27. http://dx.doi.org/10.5194/nhess-12-3217-2012.
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Abstract. The water balance of the mesocenozoic aquifers of the Algarve, in the south of Portugal has traditionally been estimated considering only direct ("autogenic") recharge from rainfall occurring in the area of the aquifers. Little importance has been attributed to so-called allogenic recharge, originating from streambed infiltration from runoff generated outside the aquifers, particularly in the Palaeozoic rocks to the north where runoff is high. The Querença-Silves (QS) aquifer is the most important aquifer of the region both for irrigation and public water supply. Several important and sensitive surface/groundwater ecotones and associated groundwater dependent ecosystems exist at the springs of the natural discharge areas of the aquifer system. A numerical flow model has been in constant development over the last few years and currently is able to reproduce the aquifer's responses to estimated direct recharge and abstraction for the years 2001–2010. However, recharge calculations for the model do not take into account allogenic recharge infiltration along influent reaches of streams. The quantification of allogenic recharge may further improve the assessment of water availability and exploitation risks. In this paper an attempt is made to quantify the average annual contribution of allogenic recharge to the QS aquifer, based on monitoring data of the principal water courses that cross the aquifer system. Significant uncertainties related to surface runoff generated within the aquifer area, as well as areal recharge were identified and the consequences for the optimization of spatial distribution of transmissivity in the groundwater flow model are also addressed.
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Rodhe, Allan. "On the Generation of Stream Runoff in Till Soils." Hydrology Research 20, no. 1 (February 1, 1989): 1–8. http://dx.doi.org/10.2166/nh.1989.0001.
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Isotope studies in Swedish till basins indicate that stream stormflow is normally dominated by pre-event water. The rapid response of the groundwater outflow to infiltration may be explained by a large increase in the hydraulic conductivity of the soil towards the ground surface. In homogeneous soils the effect of the capillary fringe may be important in building up large total head gradients towards the stream. In generating runoff peaks in the streams, the saturated discharge area contributes 100 %, by saturation overland flow. Various parts of the recharge area contribute less than 100 %, and less effectively the longer the distance to the recharge area is. The areal extent of the contributing recharge area is considerably larger than the discharge area.
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Swethamber Cheruku, G Prabhakar, and Umamaheswara Rao Boddu. "Morphological characteristics of Kanthatmakur vagu Watershed of Warangal District: Using Geographical Information System (GIS)." World Journal of Advanced Research and Reviews 17, no. 1 (January 30, 2023): 255–65. http://dx.doi.org/10.30574/wjarr.2023.17.1.0027.
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The present study relates to the morphometric analysis of Kanthatmakur vagu watershed using GIS. The GIS platform facilitates the analysis of various morphometric parameters. This watershed has higher order of 5th order. The present study has area of about 440.4 Km2 with total length of basin is 45.5 Km. Total number of streams in the basin is 635, ranging from 10 to 319. The basin area exhibits dendritic drainage pattern with bifurcation ratio ranges from 0.1 to 9.2, with mean bifurcation ration of 3.4. Length of stream of all orders are 481.8 km. Length of overland slow is 0.55 km and perimeter of the basin found to be 119.7 km. Areal aspects such as drainage density is calculated as 1.1, drainage frequency is 1.4 and drainage texture calculated as 5.3. Infiltration number of the watershed is 0.8. The watershed has 0.3 form factor ratio, 0.5 elongation ration and 0.4 circularity ratio. Relief of the watershed is 261m and ratio of relief is 6.3. The characteristics of morphological analysis of the Kanthatmakur vagu watershed has peak flow, is an elongated and less probable to flooding as well as moderate to slightly steep slope. In the watershed infiltration is high and run off will be low.
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Guo, Miaocai, and Xiaosu Yi. "Effect of Paper or Silver Nanowires-Loaded Paper Interleaves on the Electrical Conductivity and Interlaminar Fracture Toughness of Composites." Aerospace 5, no. 3 (July 19, 2018): 77. http://dx.doi.org/10.3390/aerospace5030077.
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The effect of plant-fiber paper or silver nanowires-loaded paper interleaves on the electrical conductivity and interlaminar fracture toughness of composites was studied. Highly conductive paper was prepared by surface-loaded silver nanowires. The percolation threshold appeared at about 0.4 g/m2. The surface resistivity reached 2.3 Ω/sq when the areal density of silver nanowires was 0.95 g/m2. After interleaving the conductive papers in the composite interlayers, in-plane electrical conductivity perpendicular to the fiber direction was increased by 171 times and conductivity through thickness direction was increased by 2.81 times. However, Mode I and Mode II interlaminar fracture toughness decreased by 67.3% and 66.9%, respectively. Microscopic analysis showed that the improvement of conductivity was attributable to the formation of an electrical conducting network of silver nanowires which played a role in electrical connection of carbon fiber plies and the interleaving layers. However, the density of the highly packed flat plant fibers impeded the infiltration of resin. The parallel distribution of flat fibers to the carbon plies, and poor resin-fiber interface made the interlaminar fracture occur mainly at the interface of plant fibers and resin inside the interleaves, resulting in a decline of the interlaminar fracture toughness. The surface-loading of silver nanowires further impeded the infiltration of resin in the densely packed plant fibers, resulting in further decline of the fracture toughness.
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Juhl, Anika C., Artur Schneider, Boris Ufer, Torsten Brezesinski, Jürgen Janek, and Michael Fröba. "Mesoporous hollow carbon spheres for lithium–sulfur batteries: distribution of sulfur and electrochemical performance." Beilstein Journal of Nanotechnology 7 (August 30, 2016): 1229–40. http://dx.doi.org/10.3762/bjnano.7.114.
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Hollow carbon spheres (HCS) with a nanoporous shell are promising for the use in lithium–sulfur batteries because of the large internal void offering space for sulfur and polysulfide storage and confinement. However, there is an ongoing discussion whether the cavity is accessible for sulfur. Yet no valid proof of cavity filling has been presented, mostly due to application of unsuitable high-vacuum methods for the analysis of sulfur distribution. Here we describe the distribution of sulfur in hollow carbon spheres by powder X-ray diffraction and Raman spectroscopy along with results from scanning electron microscopy and nitrogen physisorption. The results of these methods lead to the conclusion that the cavity is not accessible for sulfur infiltration. Nevertheless, HCS/sulfur composite cathodes with areal sulfur loadings of 2.0 mg·cm−2 were investigated electrochemically, showing stable cycling performance with specific capacities of about 500 mAh·g−1 based on the mass of sulfur over 500 cycles.
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Shah, Reepal D., and Vimal Mishra. "Development of an Experimental Near-Real-Time Drought Monitor for India*." Journal of Hydrometeorology 16, no. 1 (February 1, 2015): 327–45. http://dx.doi.org/10.1175/jhm-d-14-0041.1.
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Abstract Persistent and widespread drought hampers water resources management and crop production. India has faced frequent droughts over the last few decades. Despite the detrimental impacts of droughts in India, a real-time monitoring system at appropriate spatial and temporal resolution has been lacking. Here, an experimental drought monitor for India is developed that operates daily at a spatial resolution of 0.25° and provides near-real-time information on droughts. The real-time daily precipitation data are obtained from the Tropical Rainfall Measurement Mission (TRMM) while daily temperatures are obtained from the Global Ensemble Forecast System (GEFS), version 2. Near-real-time precipitation and temperatures are bias corrected using the historic precipitation and temperature data from the India Meteorological Department (IMD). Data extending from the past to near present were reconstructed by combining IMD (1969–2010) with real-time, bias-corrected TRMM and GEFS datasets (2010 onward). The experimental drought monitor provides information on meteorological, hydrological, and agricultural droughts using the standardized precipitation index (SPI), standardized runoff index (SRI), and standardized soil moisture index (SSI), respectively. Soil moisture and runoff are simulated using the Variable Infiltration Capacity (VIC) model in near–real time to estimate the severity and areal extent of agricultural and hydrological droughts. The severity and areal extent of droughts from the experimental drought monitor are successfully evaluated against a satellite-based drought severity index. The experimental drought monitor provides high-resolution drought information (district level) that can be valuable for natural resources management and policy making.
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Wuryanta, Agus. "ZONASI KERENTANAN AIR TANAH PADA BENTANG ALAM KARST DENGAN SISTEM INFORMASI GEOGRAFIS SEBAGAI DASAR PENYUSUNAN TATA RUANG." Seminar Nasional Geomatika 3 (February 15, 2019): 209. http://dx.doi.org/10.24895/sng.2018.3-0.958.
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Bentang alam karst memiliki karakter morfologi, geologi, hidrogeologi dan lingkungan hayati yang berbeda dibandingkan dengan bentang alam lainnya. Kondisi lahan di atas permukaan tanah pada bentang alam karst pada umumnya kering dan kritis, sedangkan di bawah permukaan tanah terdapat potensi sumberdaya air yang sangat berlimpah. Lokasi kajian terletak di Sub Daerah Aliran Sungai (Sub DAS) Alang, Kabupaten Wonogiri. Tujuan kajian adalah menentukan zona kerentanan air tanah dengan menggunakan metode APLIS (Altitude, Slope, Litology, Infiltration and Soils). Parameter yang digunakan adalah ketinggian, kelerengan, batuan, zona infiltrasi dan jenis tanah. Kelas kelerengan dan ketinggian diperoleh dari analisis peta kontur skala 1: 25.000, jenis tanah diperoleh dari peta tanah sedangkan jenis batuan dan infiltrasi diperoleh dari peta geologi. Masing – masing parameter dilakukan overlay dengan menggunakan perangkat lunak Sistem Informasi Geografis (SIG). Hasil kajian menunjukkan, terdapat 4 tingkat kerentanan air tanah di sub DAS Alang yaitu sangat rendah, rendah, tinggi dan sangat tinggi. Tingkat kerentanan air tanah tinggi (zona perlindungan air tanah) menempati areal paling luas yaitu 15.541,79 ha (91,75 % dari total luas sub DAS Alang). Pada wilayah ini, kegiatan yang tidak boleh dilakukan adalah penambangan dan industri karena dapat mencemari air tanah. Sedangkan tingkat kerentanan sangat rendah, rendah dan sangat tinggi berturut – turut menempati areal seluas 10,34 ha, 1.382,35 ha dan 3,64 ha. Penerapan metode APLIS dengan perangkat lunak SIG dapat digunakan untuk menentukan zona tingkat kerentanan air tanah. Disamping itu distribusi spasial zona kerentanan air tanah dapat dimanfaatkan sebagai salah satu pertimbangan didalam penyusunan tata ruang kawasan bentang alam karst.
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Harder, Phillip, John W. Pomeroy, and Warren D. Helgason. "A simple model for local-scale sensible and latent heat advection contributions to snowmelt." Hydrology and Earth System Sciences 23, no. 1 (January 2, 2019): 1–17. http://dx.doi.org/10.5194/hess-23-1-2019.
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Abstract. Local-scale advection of energy from warm snow-free surfaces to cold snow-covered surfaces is an important component of the energy balance during snow-cover depletion. Unfortunately, this process is difficult to quantify in one-dimensional snowmelt models. This paper proposes a simple sensible and latent heat advection model for snowmelt situations that can be readily coupled to one-dimensional energy balance snowmelt models. An existing advection parameterization was coupled to a conceptual frozen soil infiltration surface water retention model to estimate the areal average sensible and latent heat advection contributions to snowmelt. The proposed model compared well with observations of latent and sensible heat advection, providing confidence in the process parameterizations and the assumptions applied. Snow-covered area observations from unmanned aerial vehicle imagery were used to update and evaluate the scaling properties of snow patch area distribution and lengths. Model dynamics and snowmelt implications were explored within an idealized modelling experiment, by coupling to a one-dimensional energy balance snowmelt model. Dry, snow-free surfaces were associated with advection of dry air that compensated for positive sensible heat advection fluxes and so limited the net influence of advection on snowmelt. Latent and sensible heat advection fluxes both contributed positive fluxes to snow when snow-free surfaces were wet and enhanced net advection contributions to snowmelt. The increased net advection fluxes from wet surfaces typically develop towards the end of snowmelt and offset decreases in the one-dimensional areal average melt energy that declines with snow-covered area. The new model can be readily incorporated into existing one-dimensional snowmelt hydrology and land surface scheme models and will foster improvements in snowmelt understanding and predictions.
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Zhuo, Lu, Qiang Dai, Binru Zhao, and Dawei Han. "Soil moisture sensor network design for hydrological applications." Hydrology and Earth System Sciences 24, no. 5 (May 15, 2020): 2577–91. http://dx.doi.org/10.5194/hess-24-2577-2020.
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Abstract. Soil moisture plays an important role in the partitioning of rainfall into evapotranspiration, infiltration, and runoff, hence a vital state variable in hydrological modelling. However, due to the heterogeneity of soil moisture in space, most existing in situ observation networks rarely provide sufficient coverage to capture the catchment-scale soil moisture variations. Clearly, there is a need to develop a systematic approach for soil moisture network design, so that with the minimal number of sensors the catchment spatial soil moisture information could be captured accurately. In this study, a simple and low-data requirement method is proposed. It is based on principal component analysis (PCA) for the investigation of the network redundancy degree and K-means cluster analysis (CA) and a selection of statistical criteria for the determination of the optimal sensor number and placements. Furthermore, the long-term (10-year) 5 km surface soil moisture datasets estimated through the advanced Weather Research and Forecasting (WRF) model are used as the network design inputs. In the case of the Emilia-Romagna catchment, the results show the proposed network is very efficient in estimating the catchment-scale surface soil moisture (i.e. with NSE and r at 0.995 and 0.999, respectively, for the areal mean estimation; and 0.973 and 0.990, respectively, for the areal standard deviation estimation). To retain 90 % variance, a total of 50 sensors in a 22 124 km2 catchment is needed, and in comparison with the original number of WRF grids (828 grids), the designed network requires significantly fewer sensors. However, refinements and investigations are needed to further improve the design scheme, which are also discussed in the paper.
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Basher, L. R., C. W. Ross, and J. Dando. "Effects of carrot growing on volcanic ash soils in the Ohakune area, New Zealand." Soil Research 42, no. 3 (2004): 259. http://dx.doi.org/10.1071/sr03095.
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Effects of intensive carrot production on soils derived from young volcanic ash were determined at Ohakune, New Zealand. Erosion rates (derived from caesium-137) and key soil physical and chemical properties were determined in 3 fields with differing management history (6 and 16 years cropping) or topography (sloping and flat).Caesium-137 areal activity in cropped fields ranged from 90 to 2034 Bq/m2, compared with a reference value under long-term pasture of 602 Bq/m2. Mean areal activity was lower than the reference value in 2 sloping fields, but not in a flat field. Net erosion rates were low in both sloping fields (–16 and –5 t/ha.year), but within each field there was a wide range of erosion and deposition rates (–109 to +293 t/ha.year in Field 1 and –145 to +514 t/ha.year in Field 2). These very high rates imply total soil losses up to 238 mm and deposition up to 670 mm, consistent with observed elevation differences between the cropped fields and adjacent fields in long-term pasture and with topsoil depth variation from 145 to 1165 mm. Tillage erosion and deposition rates are high (up to c. 40 t/ha.year) but water erosion is the dominant mechanism of soil redistribution.Cropping has reduced organic matter and aggregate stability, increased bulk density in the lower part of the topsoil and subsoil, and increased aggregate size. Hydraulic conductivity was higher in the topsoil and lower in the subsoil under cropping than it was under pasture. However, it would not limit soil water movement as it was higher than typical rainfall intensities. Compacted wheel tracks were the primary control on runoff and erosion as they have low infiltration rates (4 mm/h) compared with carrot beds (853 mm/h).
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Wang, Chong, Jian-Hao Lu, Zi-Long Wang, An-Bang Wang, Hao Zhang, Wei-Kun Wang, Zhao-Qing Jin, and Li-Zhen Fan. "Synergistic Adsorption-Catalytic Sites TiN/Ta2O5 with Multidimensional Carbon Structure to Enable High-Performance Li-S Batteries." Nanomaterials 11, no. 11 (October 28, 2021): 2882. http://dx.doi.org/10.3390/nano11112882.
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Lithium-sulfur (Li-S) batteries are deemed to be one of the most optimal solutions for the next generation of high-energy-density and low-cost energy storage systems. However, the low volumetric energy density and short cycle life are a bottleneck for their commercial application. To achieve high energy density for lithium-sulfur batteries, the concept of synergistic adsorptive–catalytic sites is proposed. Base on this concept, the TiN@C/S/Ta2O5 sulfur electrode with about 90 wt% sulfur content is prepared. TiN contributes its high intrinsic electron conductivity to improve the redox reaction of polysulfides, while Ta2O5 provides strong adsorption capability toward lithium polysulfides (LiPSs). Moreover, the multidimensional carbon structure facilitates the infiltration of electrolytes and the motion of ions and electrons throughout the framework. As a result, the coin Li-S cells with TiN@C/S/Ta2O5 cathode exhibit superior cycle stability with a decent capacity retention of 56.1% over 300 cycles and low capacity fading rate of 0.192% per cycle at 0.5 C. Furthermore, the pouch cells at sulfur loading of 5.3 mg cm−2 deliver a high areal capacity of 5.8 mAh cm−2 at low electrolyte/sulfur ratio (E/S, 3.3 μL mg−1), implying a high sulfur utilization even under high sulfur loading and lean electrolyte operation.
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Wang, Zhentao, and Kathleen M. Trauth. "Development of GIS-based Python scripts to calculate a water surface profile on a landscape for wetlands decision-making." Journal of Hydroinformatics 22, no. 3 (April 9, 2020): 628–40. http://dx.doi.org/10.2166/hydro.2020.167.
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Abstract Wetlands provide many benefits for humans and the natural environment, but land-use changes have reduced their number and areal extent. Interest has grown in examining the landscape to determine those locations where, with minimal effort, it might be possible to develop a mitigation wetland – a location with sufficient water over a sufficient period of time to develop and maintain wetland functioning. This paper proposes a methodology to support the examination of the landscape for mitigation purposes through the application of open channel hydraulics principles to flow over a landscape. The methodology is part of a larger research effort ultimately combining hydrology and hydraulics, along with the landscape processes of infiltration and evapotranspiration, to perform a water balance assessment. Specifically, the methodology is implemented through readily available geographic information system tools along with Python scripts written for this study. The Python scripts automatically extract landscape characteristics from a digital elevation model and calculate hydraulic parameters that are used to determine water surface profiles using the Modified Euler's method. Multiple tests show that the script accurately produces profiles of flow between depressions over a landscape. Such determinations are the first step in understanding where water might exist on the surface to support mitigation wetland functions.
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Ma, Xing, Guillaume Lacombe, Rhett Harrison, Jianchu Xu, and Meine van Noordwijk. "Expanding Rubber Plantations in Southern China: Evidence for Hydrological Impacts." Water 11, no. 4 (March 29, 2019): 651. http://dx.doi.org/10.3390/w11040651.
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While there is increasing evidence concerning the detrimental effects of expanding rubber plantations on biodiversity and local water balances, their implications on regional hydrology remain uncertain. We studied a mesoscale watershed (100 km2) in the Xishuangbanna prefecture, Yunnan Province, China. The influence of land-cover change on streamflow recorded since 1992 was isolated from that of rainfall variability using cross-simulation matrices produced with the monthly lumped conceptual water balance model GR2M. Our results indicate a statistically significant reduction in wet and dry season streamflow from 1992 to 2002, followed by an insignificant increase until 2006. Analysis of satellite images from 1992, 2002, 2007, and 2010 shows a gradual increase in the areal percentage of rubber tree plantations at the watershed scale. However, there were marked heterogeneities in land conversions (between forest, farmland, grassland, and rubber tree plantations), and in their distribution across elevations and slopes, among the studied periods. Possible effects of this heterogeneity on hydrological processes, controlled mainly by infiltration and evapotranspiration, are discussed in light of the hydrological changes observed over the study period. We suggest pathways to improve the eco-hydrological functionalities of rubber tree plantations, particularly those enhancing dry-season base flow, and recommend how to monitor them.
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Zeleňáková, Martina, Petr Hluštík, Hany F. Abd-Elhamid, Zuzana Vranayová, Gabriel Markovič, Gabriela Hudáková, and Ladislav Tometz. "Comprehensive study of the percolation of water from surface runoff with an emphasis on the retention capacity and intensity of precipitation." Water Science and Technology 79, no. 12 (June 15, 2019): 2407–16. http://dx.doi.org/10.2166/wst.2019.243.
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Abstract Urban hydrology was created in order to improve methods of managing the runoff of precipitation in towns and protect them from flooding while also protecting public health and environment. The essence of a future solution consists in finding an acceptable compromise of an alternative solution for draining rainwater from a territory. The content of this work is a study focused on resolving the percolation of water from surface runoff and the confrontation between a field test, laboratory analysis, and numerical analysis. By confronting and subsequently proposing conditions for percolation, documents will be created for making urban drainage better and more efficient. The reason for the origin of the subject work follows from the insufficient information on infiltration systems in Slovak technical standards and, likewise, the lack of support for the percolation of water from surface runoff. This work points out the approaches, principles, and fundamentals of a proposal for percolation. The aim of the work is distribution of scientific knowledge in the field of research and solutions for the percolation of water from surface runoff, with emphasis placed on the retention capacity of the selected territory and the intensity of precipitation. A geological study (orientational, detailed or supplementary) must always be conducted with any decision on rainwater percolation in a certain locality. Its range is dependent on the difficulty and type of construction. The preliminary study of areal condition should be focused on detailed engineering-geological and hydrological information. After this work, it is concluded that the percolation of rainwater in urban areas with suitable hydrogeological condition is an effective rainwater management technology as well as protection to congestion of sewer systems.
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Uchida, K., M. Morozumi, R. Yamaguchi, and S. Tateyama. "Diffuse Leptomeningeal Malignant Histiocytosis in the Brain and Spinal Cord of a Tibetan Terrier." Veterinary Pathology 38, no. 2 (March 2001): 219–22. http://dx.doi.org/10.1354/vp.38-2-219.
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An 8-year-old male Tibetan Terrier showed prolonged astasia, complete paralysis, ticlike signs, and seizure and died 2 months after the onset of symptoms. Histopathologically, there was moderate to severe infiltration of pleomorphic histiocytic mononuclear cells bilaterally in the basiarachnoidal and ventricular areas of the brain. The spinal dura mater, arachnoidal space, and leptomeninges were also affected by infiltrative proliferation of these mononuclear cells. The infiltrating cells had the morphologic characteristics of histiocytes but exhibited moderate pleomorphism and atypia, with abundant mitotic figures. With immunohistochemistry and lectin histochemistry, most of the infiltrating cells were positive for lysozyme and lectin RCA-1 and negative for glial fibrillary acid protein, suggesting that they were of monocytic/histiocytic-origin. Positive proliferating cell nuclear antigen immunostaining demonstrated that most nuclei of the histiocytic cells were in the S phase of the cell cycle, consistent with a proliferating population of cells. Based on these findings, the case was diagnosed as diffuse leptomeningeal malignant histiocytosis.
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Su, Fengge, Yang Hong, and Dennis P. Lettenmaier. "Evaluation of TRMM Multisatellite Precipitation Analysis (TMPA) and Its Utility in Hydrologic Prediction in the La Plata Basin." Journal of Hydrometeorology 9, no. 4 (August 1, 2008): 622–40. http://dx.doi.org/10.1175/2007jhm944.1.
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Abstract Satellite-based precipitation estimates with high spatial and temporal resolution and large areal coverage provide a potential alternative source of forcing data for hydrological models in regions where conventional in situ precipitation measurements are not readily available. The La Plata basin in South America provides a good example of a case where the use of satellite-derived precipitation could be beneficial. This study evaluates basinwide precipitation estimates from 9 yr (1998–2006) of Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA; 3B42 V.6) through comparison with available gauged data and the Variable Infiltration Capacity (VIC) semidistributed hydrology model applied to the La Plata basin. In general, the TMPA estimates agreed well with the gridded gauge data at monthly time scales, most likely because of the monthly adjustment to gauges performed in TMPA. The agreement between TMPA and gauge precipitation estimates was reduced at daily time scales, particularly for high rain rates. The TMPA-driven hydrologic model simulations were able to capture the daily flooding events and to represent low flows, although peak flows tended to be biased upward. There was a good agreement between TMPA-driven simulated flows in terms of their reproduction of seasonal and interannual streamflow variability. This analysis shows that TMPA has potential for hydrologic forecasting in data-sparse regions.
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Purwanto, Herri, Amiwarti Amiwarti, Adiguna Adiguna, and Reffanda Kurniawan. "SOSIALISASI LUBANG RESAPAN BIOPORI DI MAN 1 OGAN ILIR INDRALAYA." Jurnal PkM Pengabdian kepada Masyarakat 4, no. 1 (July 13, 2021): 33. http://dx.doi.org/10.30998/jurnalpkm.v4i1.5639.
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<p><strong>Abstrak</strong></p><p>Kegiatan Pengabdian Pada Masyarakat (PPM) yang dilakukan oleh dosen Prodi Teknik Sipil Universitas PGRI Palembang di MAN 1 Ogan Ilir Indralaya ini bertujuan agar siswa dan guru dapat mengenal dan menambah pengetahuan tentang lubang resapan biopori (LRB) dan manfaatnya bagi lingkungan sekolah. Dimana di areal MAN 1 Ogan Ilir sering tergenang air saat hujan turun. Metode yang dilakukan adalah dengan memberi penyuluhan dan praktek langsung di halaman sekolah. Peserta yang hadir yaitu guru dan siswa MAN 1 Ogan Ilir sangat antusias dengan kegiatan yang dilaksanakan, sehingga akhirnya mereka mempraktekkan sendiri cara membuat LRB. Dan juga dijelaskan manfaat lain dari LRB adalah dapat membuat pupuk kompos organik, dengan cara memasukkan sampah daun yang ada di lingkungan sekolah ke dalam LRB. Dan dalam waktu 2 bulan pupuk kompos sudah dapat dipanen. Sehingga pemanfaatan Lubang Resapan Biopori (LRB) di MAN 1 Ogan Ilir sangat cocok</p><p> </p><p><strong>Abstract</strong></p><p><em>Community Service Activities (PPM) carried out by lecturers of the Civil Engineering Study Program, PGRI Palembang University at MAN 1 Ogan Ilir Indralaya aims so that students and teachers can get to know and increase knowledge about biopore infiltration holes (LRB) and its benefits for the school environment. Where in the area of MAN 1 Ogan Ilir is often flooded when it rains. The method used is to provide counseling and practice directly in the school yard. The participants who attended were students and teachers of MAN 1 Ogan Ilir were very enthusiastic about the activities being carried out, so that they finally practiced how to make LRBs themselves. And also explained the other benefits of LRB is that it can make organic compost, by inserting leaf litter from the school environment into the LRB. And within 2 months the compost can be harvested. So that the use of Biopore Infiltration Holes (LRB) at MAN 1 Ogan Ilir is very suitable</em></p>
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Oryngozha Ye.Ye.,, Vorobiev A.Ye.,, Zhangalieva M.,, and Uteshev I. Zh.,. "STUDY OF MINING-GEOLOGICAL CHARACTERISTICS OF URANIUM DEPOSITS OF KAZAKHSTAN FOR DEVELOPMENT BY UNDERGROUND WELL LEACHING." NEWS of National Academy of Sciences of the Republic of Kazakhstan 5, no. 443 (October 15, 2020): 156–64. http://dx.doi.org/10.32014/2020.2518-170x.116.
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Existing traditional uranium mining technologies have major drawbacks, do not meet the requirements of a market economy, are ineffective, require the use of a large number of expensive injection and pumping wells, low leaching rates, require a large consumption of chemical reagent, sulfuric acid (to produce 1 ton of uranium concentrate requires a flow of 100 tons sulfuric acid). Here, a productive solution refers to a chemical solution containing the concentration of the leached therein of various useful components (metals), including uranium, dissolved therein. In the practice of exploitation of hydrogenous uranium deposits, the arrangement of technological wells has been adopted: linear (or in-line), areal (or cellular) and combined. Our proposed innovative technology for the exploitation of hydrogenous uranium deposits will be developed on the principle of piston wells using the effect of activation of a chemical solution supplied to the array of a hydrogenated uranium layer for leaching and other useful components. In the process of activation, the chemical solution is heated to t = 70 ° C, the water in the solution becomes a good solvent. Pumping wells are used as piston wells without changing the design, i.e. pumping wells are also used as injection wells. This article presents the mining and geological characteristics of technogenic uranium deposits in Kazakhstan. The basis of the raw material base of Kazakhstan's uranium is exogenous type deposits, combined into a subgroup called “infiltration”. Uranium infiltration deposits are formed by groundwater associated with regional formation zones and zones of soil-layer oxidation. The development and implementation of the method of underground well leaching of uranium (UWL) is one of the most important scientific and technical achievements of the mining industry. The main advantages of the underground leaching method compared to traditional mining methods of developing deposits are as follows: the possibility of involving poor and off-balance ores in deposits with complex geological and hydrogeological conditions, but with large reserves of uranium; Significant reduction in capital investments and terms of commissioning deposits; improving working conditions, reducing the number of miners and increasing labor productivity by 2.5-3.5 times; reducing the negative impact of uranium mining on the environ-ment.
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Kounis, G. D., and K. G. Kounis. "INFILTRATION, EFFECTIVE POROSITY, TRANSMISSIBILITY AND CRITICAL YIELD OF WATER WELLS IN THE CARBONATE FISSURED AQUIFERS OF ATTICA – A CONTRIBUTION TO THE REGIONAL AND MANAGERIAL HYDROGEOLOGY." Bulletin of the Geological Society of Greece 43, no. 4 (January 25, 2017): 1758. http://dx.doi.org/10.12681/bgsg.11361.
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In the hydrogeological practice and the groundwater resources management the accurate knowledge on the infiltration, effective porosity, transmissibility, and on the sustainable yield of water wells is of fundamental value. It is so, because these parameters are the information primarily required in prediction and decisions relevant to the ground water abstractions and the hydrogeological evaluation of specific sites. In this paper, we present these quantities from the carbonate fissured formations of Attica, non metamorphic (limestones, dolomitic limestones, dolomites ) and metamorphic (marbles), which all are of great areal extent and thus of great interest for groundwater exploitation. In addition, they show good geomorphological, structural and lithologic resemblance with analogous formations elsewhere in this country, so that figures calculated can be reliably transferred for use. In our work we used methods of increased reliability, and having known precipitation (P) we estimated — The Infiltration Index (Ic) from the yield of springs of well defined hydrogeological catchments (natural lysimeters) and results found fall in the range of values 0.38P < Ic < 0.42P — The Effective Porosity (pe), obviously secondary because of the nature of the carbonate aquifers ( fissure flow aquifers ). We calculated it from groundwater level hydrograph and values found are in between 1.31%< pe < 6.91% with the most common in between 1.58%< pe < 4.8% — The Transmissibility (T), we calculated from pumping tests, with Jacob method, using semilogarithmic plots of drawdowns (s) versus time (t) from start of pumping. Values found are mostly (70%)in the range 10m3 /h.m < T < 75m3 /h.m — The Critical Yield (Qc) of water wells we calculated from the “characteristic well curve” Q vs. s (with Q and s standing for yield and drawdown respectively). Values are mostly in between 15m3 /h < Qc <75 m3 /h. Cretaceous limestones showed the best of the parameters, followed by the marbles free of schist in- Δελτίο της Ελληνικής Γεωλογικής Εταιρίας, 2010 Bulletin of the Geological Society of Greece, 2010 Πρακτικά 12ου Διεθνούς Συνεδρίου Proceedings of the 12th International Congress Πάτρα, Μάιος 2010 Patras, May, 2010 tercalations and distant from schist boundary . Karstic processes on the fracture network, structures vulnerable to tectonic extension, like anticlines and tension faulting zones are the underlying reasons for better hydrogeologic performance and thus for higher values of the parameters studied. Dolomites outside the previous zones show very low values .
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Morita, T., A. Shimada, S. Yashiro, T. Takeuchi, Y. Hikasa, Y. Okamoto, and Y. Mabuchi. "Myofiber Expression of Class I Major Histocompatibility Complex Accompanied by CD8+ T-cell-associated Myofiber Injury in a Case of Canine Polymyositis." Veterinary Pathology 39, no. 4 (July 2002): 512–15. http://dx.doi.org/10.1354/vp.39-4-512.
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A 7-year-old female Labrador Retriever dog showed extreme muscular weakness, muscle wasting, dysbasia, and mild dysphagia. An elevated value of creatine kinase (335 IU/liter) in the serum was detected. Electromyographic findings included increased insertional activity, fibrillation potentials, and bizarre high-frequency repetitive potentials. Histopathologic examination of skeletal muscles revealed myofiber necrosis and phagocytosis, regeneration of myofibers, and perivascular, perimysial, and endomysial infiltrations of lymphocytes, macrophages and plasma cells. Immunohistochemical evaluation demonstrated that infiltrative cells in the early stage of myositis were CD8+ T-cells and that an increased expression of major histocompatibility complex (MHC) class I was apparent on the surface of nonnecrotic muscle fibers. In contrast, many CD3+ cells (T cells) and HLA-DR-positive macrophages and B lymphocytes were found in the severely affected areas. These results suggest that both expression of MHC class I and CD8+ T-cell infiltration may play an important role in initiation of myositis. These histopathologic findings resemble those reported in naturally occurring polymyositis in humans.
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Hřibová, Šárka, Helena Zlámalová Gargošová, and Milada Vávrová. "Sorption ability of the soil and its impact on environmental contamination." Interdisciplinary Toxicology 7, no. 4 (December 1, 2014): 177–83. http://dx.doi.org/10.2478/intox-2014-0025.
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ABSTRACT From the physical point of view, soil is a heterogenic polydisperse system. It often becomes a place of a secondary contamination during extinguishing uncontrolled areal fires in nature. Foam extinguishing agents (FEAs), used at these events, basically contain surface active substances and perfluorinated compounds. These tend to be captured in the soil matrix due to their specific properties. Contaminants could be partly flushed out with rainwater, which causes several times dilution of contamination and lower ecotoxic activity. However in the dry season, foam solution infiltrates into the bed soil without any dilution. This study deals with the direct influence of soil the sorption complex on ecotoxicity of five selected FEAs, i.e. Expyrol F 15, Finiflam F 15, Moussol APS F 15, Pyrocool B and Sthamex F 15. The substances tested were prepared in concentration of work solution and then applied on standard soil matrix LUFA 2.3. For experimental purposes, a column infiltration apparatus was designed and compiled. Filtrates were collected and then tested using the plant organisms Sinapis alba and Allium cepa L. The study compared ecotoxicologic effects of filtrates with an original work solution. Moussol APS F 15 seems to be the least ecotoxic of the FEAs tested. A direct influence of soil sorption complex onto ecotoxicity reduction was also established. This finding demonstrates the sorption ability of soil particles and ion exchange activity of the soil matrix. It is a positive finding for biota of aquatic environment, yet at the expense of those in soil
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Buzzard, Quinn, Jeff B. Langman, David Behrens, and James G. Moberly. "Monitoring the Ambient Seismic Field to Track Groundwater at a Mountain–Front Recharge Zone." Geosciences 13, no. 1 (December 28, 2022): 9. http://dx.doi.org/10.3390/geosciences13010009.
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The heterogeneity of the fractured-basalt and interbedded-sediment aquifer along the eastern margin of the Columbia Plateau Regional Aquifer System has presented challenges to resource managers in quantifying recharge and estimating sustainable withdrawals. Previous studies indicated recharge pathways in alluvial sediments atop a mountain–front interface upgradient of the basalt flows. In this sedimentary zone, six seismic stations were deployed for one year to detect velocity changes in low-frequency seismic waves that could be correlated to changes in groundwater recorded by a well transducer near the center of the seismic station network. Waveforms in the 1−5 Hz range were recorded at each station to determine changes in wave velocities between station pairs and correlate these velocity changes to changes in groundwater levels. The velocity–groundwater relation allowed for estimation of daily groundwater levels beneath the seismic station network. Existing hydrogeologic information was used to estimate hydraulic gradients and hydraulic conductivities, which allowed for the calculation of the daily volume of recharge passing beneath the seismic stations and into the confined aquifer system. The daily recharge volumes across the seismic station network were summed for comparison of the total annual recharge calculated from the change in seismic wave velocities (154,660 m3) to a flow model calculation of recharge based on areal precipitation and infiltration (26,250 m3). The 6× greater recharge estimated from the seismic wave velocity changes for this portion of the recharge zone is attributed to preferential pathways of high hydraulic conductivity and greater depth associated with paleochannels beneath the seismic station network.
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Weber, Juan Francisco. "Estimación de los parámetros del modelo de infiltración de Philip para áreas permeables del ejido urbano de la ciudad de Córdoba, Argentina." Aqua-LAC 7, no. 1 (March 31, 2015): 39–48. http://dx.doi.org/10.29104/phi-aqualac/2015-v7-1-05.
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Se presentan parámetros para el modelo de infiltración de Philip calibrados a partir de los resultados obtenidos en una campaña de medición in situ en la ciudad de Córdoba (Argentina). Como instrumento se utilizó un micro-simulador de lluvia portátil diseñado y construido por este grupo de trabajo. Este equipo, que es completamente desarmable y define una parcela de ensayo de 1 m², permite generar lluvias de intensidades comprendidas entre los 65 y 120 mm/h. La selección de los sitios de ensayo respondió al tipo y el uso del suelo. A su vez, se consideraron distintas condiciones de humedad inicial. La campaña de medición se extendió durante 7 meses, realizando entre 2 y 3 ensayos por semana. Los valores medidos fueron digitalizados y procesados, construyéndose las curvas de infiltración acumulada y tasa de infiltración en función del tiempo. A partir de estos valores, se ajustaron los parámetros S y K del modelo mencionado, a través de un procedimiento recursivo especialmente desarrollado que resultó altamente eficiente. El grado de ajuste alcanzado fue muy satisfactorio, con valores de R² medios de 0,999. Se considera que estos parámetros representan un aporte original al conocimiento de la hidrología urbana en la ciudad de Córdoba (Argentina).
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ROGOWSKI, ANDREW S. "Catchment infiltration II: Contributing areas." Transactions in GIS 1, no. 4 (October 1996): 267–84. http://dx.doi.org/10.1111/j.1467-9671.1996.tb00051.x.
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Andreadis, Konstantinos M., Ding Liang, Leung Tsang, Dennis P. Lettenmaier, and Edward G. Josberger. "Characterization of Errors in a Coupled Snow Hydrology–Microwave Emission Model." Journal of Hydrometeorology 9, no. 1 (February 1, 2008): 149–64. http://dx.doi.org/10.1175/2007jhm885.1.
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Abstract Traditional approaches to the direct estimation of snow properties from passive microwave remote sensing have been plagued by limitations such as the tendency of estimates to saturate for moderately deep snowpacks and the effects of mixed land cover within remotely sensed pixels. An alternative approach is to assimilate satellite microwave emission observations directly, which requires embedding an accurate microwave emissions model into a hydrologic prediction scheme, as well as quantitative information of model and observation errors. In this study a coupled snow hydrology [Variable Infiltration Capacity (VIC)] and microwave emission [Dense Media Radiative Transfer (DMRT)] model are evaluated using multiscale brightness temperature (TB) measurements from the Cold Land Processes Experiment (CLPX). The ability of VIC to reproduce snowpack properties is shown with the use of snow pit measurements, while TB model predictions are evaluated through comparison with Ground-Based Microwave Radiometer (GBMR), aircraft [Polarimetric Scanning Radiometer (PSR)], and satellite [Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E)] TB measurements. Limitations of the model at the point scale were not as evident when comparing areal estimates. The coupled model was able to reproduce the TB spatial patterns observed by PSR in two of three sites. However, this was mostly due to the presence of relatively dense forest cover. An interesting result occurs when examining the spatial scaling behavior of the higher-resolution errors; the satellite-scale error is well approximated by the mode of the (spatial) histogram of errors at the smaller scale. In addition, TB prediction errors were almost invariant when aggregated to the satellite scale, while forest-cover fractions greater than 30% had a significant effect on TB predictions.
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Mishra, Vimal, Keith A. Cherkauer, and Shraddhanand Shukla. "Assessment of Drought due to Historic Climate Variability and Projected Future Climate Change in the Midwestern United States." Journal of Hydrometeorology 11, no. 1 (February 1, 2010): 46–68. http://dx.doi.org/10.1175/2009jhm1156.1.
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Abstract Understanding the occurrence and variability of drought events in historic and projected future climate is essential to managing natural resources and setting policy. The Midwest region is a key contributor in corn and soybean production, and the occurrence of droughts may affect both quantity and quality of these crops. Soil moisture observations play an essential role in understanding the severity and persistence of drought. Considering the scarcity of the long-term soil moisture datasets, soil moisture observations in Illinois have been one of the best datasets for studies of soil moisture. In the present study, the authors use the existing observational dataset and then reconstruct long-term historic time series (1916–2007) of soil moisture data using a land surface model to study the effects of historic climate variability and projected future climate change on regional-scale (Illinois and Indiana) drought. The objectives of this study are to (i) estimate changes and trends associated with climate variables in historic climate variability (1916–2007) and in projected future climate change (2009–99) and (ii) identify regional-scale droughts and associated severity, areal extent, and temporal extent under historic and projected future climate using reconstructed soil moisture data and gridded climatology for the period 1916–2007 using the Variable Infiltration Capacity (VIC) model. The authors reconstructed the soil moisture for a long-term (1916–2007) historic time series using the VIC model, which was calibrated for monthly streamflow and soil moisture at eight U.S. Geological Survey (USGS) gauge stations and Illinois Climate Network’s (ICN) soil moisture stations, respectively, and then it was evaluated for soil moisture, persistence of soil moisture, and soil temperature and heat fluxes. After calibration and evaluation, the VIC model was implemented for historic (1916–2007) and projected future climate (2009–99) periods across the study domain. The nonparametric Mann–Kendall test was used to estimate trends using the gridded climatology of precipitation and air temperature variables. Trends were also estimated for annual anomalies of soil moisture variables, snow water equivalent, and total runoff using a long-term time series of the historic period. Results indicate that precipitation, minimum air temperature, total column soil moisture, and runoff have experienced upward trends, whereas maximum air temperature, frozen soil moisture, and snow water equivalent experienced downward trends. Furthermore, the decreasing trends were significant for the frozen soil moisture in the study domain. The results demonstrate that retrospective drought periods and their severity were reconstructed using model-simulated data. Results also indicate that the study region is experiencing reduced extreme and exceptional droughts with lesser areal extent in recent decades.
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Veldkamp, Ted Isis Elize, Floris Cornelis Boogaard, and Jeroen Kluck. "Unlocking the Potential of Permeable Pavements in Practice: A Large-Scale Field Study of Performance Factors of Permeable Pavements in The Netherlands." Water 14, no. 13 (June 29, 2022): 2080. http://dx.doi.org/10.3390/w14132080.
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Infiltrating pavements are potentially effective climate adaptation measures to counteract arising challenges related to flooding and drought in urban areas. However, they are susceptible to clogging causing premature degradation. As part of the Dutch Delta Plan, Dutch municipalities were encouraged to put infiltrating pavements into practice. Disappointing experiences made a significant number of municipalities decide, however, to stop further implementation. A need existed to better understand how infiltrating pavements function in practice. Through 81 full-scale infiltration tests, we investigated the performance of infiltrating pavements in practice. Most pavements function well above Dutch and international standards. However, variation was found to be high. Infiltration rates decrease over time. Age alone, however, is not a sufficient explanatory factor. Other factors, such as environmental or system characteristics, are of influence here. Maintenance can play a major role in preserving/improving the performance of infiltrating pavements in practice. While our results provide the first indication of the functioning of infiltrating pavement in practice, only with multi-year measurements following a strict monitoring protocol can the longer-term effects of environmental factors and maintenance actually be determined, providing the basis for the development of an optimal maintenance schedule and associated cost–benefit assessments to the added value of this type of climate adaptation.
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Christopherson, Kent W., Antoinette F. Hood, Jeffrey B. Travers, Heather Ramsey, and Robert A. Hromas. "Endothelial induction of the T-cell chemokine CCL21 in T-cell autoimmune diseases." Blood 101, no. 3 (February 1, 2003): 801–6. http://dx.doi.org/10.1182/blood-2002-05-1586.
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Abstract The signals that mediate T-cell infiltration during T-cell autoimmune diseases are poorly understood. The chemokine CCL21 (originally isolated by us and others as Exodus-2/6Ckine/SLC/TCA4) is highly potent and highly specific for stimulating T-cell migration. However, it is thought to be expressed only in secondary lymphoid organs, directing naive T cells to areas of antigen presentation. It is not thought to play a role in T-cell effector function during a normal immune response. In this study we tested the expression of T-cell chemokines and their receptors during T-cell autoimmune infiltrative skin diseases. By using immunohistology it was found that the expression of CCL21 but not CCL19 or 20 was highly induced in endothelial cells of T-cell autoimmune diseases. The receptor for CCL21, CCR7, was also found to be highly expressed on the infiltrating T cells, most of which expressed the memory CD45Ro phenotype. These data imply that the usual loss of CCL21 responsiveness in the normal development of memory T-cell effector function does not hold for autoimmune skin diseases.
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Akbari, Hamed, Luke Macyszyn, Xiao Da, Michel Bilello, Ronald L. Wolf, Maria Martinez-Lage, George Biros, Michelle Alonso-Basanta, Donald M. O'Rourke, and Christos Davatzikos. "Imaging Surrogates of Infiltration Obtained Via Multiparametric Imaging Pattern Analysis Predict Subsequent Location of Recurrence of Glioblastoma." Neurosurgery 78, no. 4 (January 19, 2016): 572–80. http://dx.doi.org/10.1227/neu.0000000000001202.
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Abstract BACKGROUND: Glioblastoma is an aggressive and highly infiltrative brain cancer. Standard surgical resection is guided by enhancement on postcontrast T1-weighted (T1) magnetic resonance imaging, which is insufficient for delineating surrounding infiltrating tumor. OBJECTIVE: To develop imaging biomarkers that delineate areas of tumor infiltration and predict early recurrence in peritumoral tissue. Such markers would enable intensive, yet targeted, surgery and radiotherapy, thereby potentially delaying recurrence and prolonging survival. METHODS: Preoperative multiparametric magnetic resonance images (T1, T1-gadolinium, T2-weighted, T2-weighted fluid-attenuated inversion recovery, diffusion tensor imaging, and dynamic susceptibility contrast-enhanced magnetic resonance images) from 31 patients were combined using machine learning methods, thereby creating predictive spatial maps of infiltrated peritumoral tissue. Cross-validation was used in the retrospective cohort to achieve generalizable biomarkers. Subsequently, the imaging signatures learned from the retrospective study were used in a replication cohort of 34 new patients. Spatial maps representing the likelihood of tumor infiltration and future early recurrence were compared with regions of recurrence on postresection follow-up studies with pathology confirmation. RESULTS: This technique produced predictions of early recurrence with a mean area under the curve of 0.84, sensitivity of 91%, specificity of 93%, and odds ratio estimates of 9.29 (99% confidence interval: 8.95-9.65) for tissue predicted to be heavily infiltrated in the replication study. Regions of tumor recurrence were found to have subtle, yet fairly distinctive multiparametric imaging signatures when analyzed quantitatively by pattern analysis and machine learning. CONCLUSION: Visually imperceptible imaging patterns discovered via multiparametric pattern analysis methods were found to estimate the extent of infiltration and location of future tumor recurrence, paving the way for improved targeted treatment.
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Mishra, Vimal, Reepal Shah, Syed Azhar, Harsh Shah, Parth Modi, and Rohini Kumar. "Reconstruction of droughts in India using multiple land-surface models (1951–2015)." Hydrology and Earth System Sciences 22, no. 4 (April 16, 2018): 2269–84. http://dx.doi.org/10.5194/hess-22-2269-2018.
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Abstract. India has witnessed some of the most severe historical droughts in the current decade, and severity, frequency, and areal extent of droughts have been increasing. As a large part of the population of India is dependent on agriculture, soil moisture drought affecting agricultural activities (crop yields) has significant impacts on socio-economic conditions. Due to limited observations, soil moisture is generally simulated using land-surface hydrological models (LSMs); however, these LSM outputs have uncertainty due to many factors, including errors in forcing data and model parameterization. Here we reconstruct agricultural drought events over India during the period of 1951–2015 based on simulated soil moisture from three LSMs, the Variable Infiltration Capacity (VIC), the Noah, and the Community Land Model (CLM). Based on simulations from the three LSMs, we find that major drought events occurred in 1987, 2002, and 2015 during the monsoon season (June through September). During the Rabi season (November through February), major soil moisture droughts occurred in 1966, 1973, 2001, and 2003. Soil moisture droughts estimated from the three LSMs are comparable in terms of their spatial coverage; however, differences are found in drought severity. Moreover, we find a higher uncertainty in simulated drought characteristics over a large part of India during the major crop-growing season (Rabi season, November to February: NDJF) compared to those of the monsoon season (June to September: JJAS). Furthermore, uncertainty in drought estimates is higher for severe and localized droughts. Higher uncertainty in the soil moisture droughts is largely due to the difference in model parameterizations (especially soil depth), resulting in different persistence of soil moisture simulated by the three LSMs. Our study highlights the importance of accounting for the LSMs' uncertainty and consideration of the multi-model ensemble system for the real-time monitoring and prediction of drought over India.
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Gray, D. M., P. G. Landine, and R. J. Granger. "Simulating infiltration into frozen Prairie soils in streamflow models." Canadian Journal of Earth Sciences 22, no. 3 (March 1, 1985): 464–72. http://dx.doi.org/10.1139/e85-045.
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A major limitation of existing operational systems when applied to forecasting or synthesizing streamflow from snowmelt on watersheds in many pans of central and northern Canada is that they are incapable of accurately simulating the process of infiltration into frozen soils. The results and discussion in the paper provide a method of overcoming the problem in areas of climatic and physiographic conditions similar to those of the Prairies.Details outlining the development of a model describing snowmelt infiltration into frozen soils are presented. The model is based on the concept that for practical purposes the infiltration potential of frozen soils may be generally categorized as (1) restricted: impervious; (2) unlimited: capable of infiltrating the snow-cover water equivalent; and (3) limited: infiltration is governed by the snow-cover water equivalent and the ice content of the soil at the time of melt. An empirical relationship for calculating infiltration into frozen soils of "limited" potential is given. The improvement in performance of the United States National Weather Service river forecasting system—Sacramento model (NWSRFS) in synthesizing streamflow from snowmelt on a small watershed in western Saskatchewan gained through the use of the infiltration model is demonstrated. Different procedures of interfacing an infiltration model with an operational system, the NWSRFS, are presented, discussed, and evaluated.