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161.
Jan Oliver Wallgrün Morteza Karimzadeh Alan M. MacEachren Scott Pezanowski 《International journal of geographical information science》2018,32(1):1-29
In this article, we present the GeoCorpora corpus building framework and software tools as well as a geo-annotated Twitter corpus built with these tools to foster research and development in the areas of microblog/Twitter geoparsing and geographic information retrieval. The developed framework employs crowdsourcing and geovisual analytics to support the construction of large corpora of text in which the mentioned location entities are identified and geolocated to toponyms in existing geographical gazetteers. We describe how the approach has been applied to build a corpus of geo-annotated tweets that will be made freely available to the research community alongside this article to support the evaluation, comparison and training of geoparsers. Additionally, we report lessons learned related to corpus construction for geoparsing as well as insights about the notions of place and natural spatial language that we derive from application of the framework to building this corpus. 相似文献
162.
Moghadam Seyed Iman Taheri Ehsan Ahmadi Morteza Ghoreishian Amiri Seyed Ali 《Acta Geotechnica》2022,17(10):4359-4375
Acta Geotechnica - This paper presents a constitutive model enabled to simulate monotonic and cyclic behaviour of clay and sand in a unified framework. The bounding surface concept has been... 相似文献
163.
Aida Hashemi Nasab Hossein Ansary Seyed Hossein Sanaei-Nejad 《Arabian Journal of Geosciences》2018,11(14):390
In arid to semi-arid climates, monitoring drought is very complicated because of different hydrometeorology variables effect on it. It is proposed in this paper to develop Fuzzy Integrated Drought Index (FIDI) which combines most important effective factors in developing drought. At first, Variable Infiltration Capacity (VIC) model calibrated simulated runoff to outlet basin runoff data for years 1993–1995. Results represent high performance of model in simulating runoff of outlet basin. Then, Precipitation Anomaly Percentage Index (PAPI), actual Evapotranspiration Anomaly Percentage Index (EAPI), Runoff Anomaly Percentage Index (RAPI), and Soil Moisture Anomaly Percentage Index (SMAPI) were constructed. FIDI was compared with the PAPI, RAPI and SMAPI for the period of 1985 to 2014. The results indicate that (1) the FIDI has more ability in determining start and persistence of drought event compared with PAPI, RAPI, and SMAPI; (2) in the low time scales, PAPI and SMAPI have high correlation with FIDI, and in the higher time scales, RAPI has the high correlation with FIDI; (3) spatially, the middle, west, and portion of north have higher drought risk in the Neyshabour basin. 相似文献
164.
165.
Selenium transport and transformation were simulated in a soil column. A one‐dimensional dynamic mathematical and computer model is formulated to simulate, selenate, selenite, selenomethionine, organic selenium, and gaseous selenium. This computer model is based on the mass balance equation, including convective transport, dispersive transport, surface adsorption, oxidation and reduction, volatilization, chemical and biological transformation. The mathematical solution is obtained by the finite difference implicit method. The model was verified by comparison of model results with experimental measurements and also using mass balance calculations in each time step of calculation. For example after 4 days of simulation, the simulated value of adsorbed selenate for depth of 20 cm is 0·2 µmol kg?1 and the measured value is 0·25 µmol kg?1. Therefore simulated results are in good agreement with measured values. With this study and its results the distribution of various forms of selenium in soil column to ground water table can be predicted. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
166.
Seyed Ali Jozi Maryam Sohrabi Balsini Arman Jamshidi 《Journal of the Indian Society of Remote Sensing》2013,41(3):577-585
Protected areas are established to conserve unique features and biodiversity of the nature. Accordingly, wherever has one of the natural, ecological and/or cultural values it should be considered a protected area. Kave-Deh No-hunting Area is located on extremely east of Tehran Province in an area of 94,961 ha. Due to rich and diverse land cover, distinctive wildlife species, and unique monuments the area was selected as a case study to examine the possibility of its promotion to the protected area using Spatial Multi Criteria Evaluation (SMCE) Method. For this purpose, the relevant criteria were identified by Delphi method. After finalization of the most important criteria by Delphi panelists, the map layers were prepared at the scale of 1:100000, in the environment of GIS Software. Afterwards, the map layers were divided into factors and constraints of which factors were standardized by S-shaped membership functions of fuzzy logic. The dimensionless factor maps were weighted using Analytical Hierarchy Process (AHP) Method in the environment of Expert Choice Software. Subsequently, a mathematical equation was extracted to conduct the land suitability analysis. The Weighted Linear Combination (WLC) Method was applied to overlay the map layers and obtain the final ‘nature conservation’ land use map. The final land suitability map showed that 34,687 ha of whole study area (equal to 37 %) have the potentiality for promotion to the protected area. 相似文献
167.
AbstractKnowledge of the relationship between rainfall intensity and kinetic energy and its variations in time and space is important for the prediction of erosion hazard. Kinetic energy and erosivity are also strongly controlled by raindrop size. However, studies on raindrop measurement and different practical techniques have been rarely documented. The current study therefore aimed to apply existing raindrop-size measurement techniques—the photographic, flour-pellet and stain methods, as well as an innovative flour-stain method—and to evaluate their applicability at several intensities in Mazandaran Province, Iran. The distribution of raindrop size obtained by the different methods was recorded and compared with those obtained through applying a high-speed imaging technique. All the analyses were made with the help of a SPSS software package. The results showed that the raindrop diameters ranged from 0.2 to 5.16 mm at different rainfall intensities. Statistical comparison of the methods using the Duncan test showed that the flour-pellet method presented similar results to the photographic technique; it was concluded that this can be used as a practical and inexpensive method to estimate a wide range of raindrop sizes.Editor Z.W. KundzewiczCitation Sadeghi, S.H., Abdollahi, Z., and Khaledi Darvishan, A., 2013. Experimental comparison of some techniques for estimating natural raindrop size distribution on the south coast of the Caspian Sea, Iran. Hydrological Sciences Journal, 58 (6), 1374–1382. 相似文献
168.
The aim of present study was to improve compost quality as well as to achieve an optimum C/N ratio in compost, reduction in heavy metal content and increased water‐holding capacity of composting piles in arid areas. Four windrow compost piles were prepared by mixing sawdust at various dosages with municipal solid waste (MSW). The sawdust was mixed with MSW at 0% (MSW0), 16% (MSW16), 32% (MSW32), and 70% (MSW70) on dry weight basis. The compost piles were monitored daily by recording the temperature, while, weekly measurement was done on C/N ratio, moisture, pH, and electrical conductivity (EC). The addition of 16% sawdust increased the initial C/N to the optimum level and decreased N loss during the composting process. The MSW16 and MSW32 exhibited better temperature dynamics and their composting period seemed to be shorter than that of MSW0 and MSW70. Moreover, addition of sawdust caused lowering of moisture loss from the composting piles. Sawdust admixtures also produced lowering of pH and EC values and led to lower heavy metal content in final products. The quality of the final compost makes it possible to propose the use of this experimental procedure for building up a novel mass reduction of the initial composted waste mixtures. 相似文献
169.
Ali Akbar Shahsavari Kamal Khodaei Farhad Asadian Farhad Ahmadi Seyed Mohammad Zamanzadeh 《Environmental Earth Sciences》2012,65(1):231-239
Study area with an area of about 415 km2 is located from 31°40′ to 32°05′ northern latitudes and 48°45′ to 49°00′ eastern longitudes 85 km to the north-east of Ahwaz
city, in the north of Khuzestan province, and south west of Iran. The purpose of this study is: (1) the determination of the
pesticides concentration in the groundwater of the Shushtar plain (Mian-Ab) and (2) the assessment of geology, hydrogeology
and anthropogenic activities impacts the groundwater quality. Thirty-seven groundwater samples were taken from product wells
based on the standard methods. A simple and efficient automated method for extraction and preconcentration was used. In this
method, a pyrrole-based polymer was synthesized and applied as an efficient sorbent for micro-solid-phase extraction. After
extraction, analytes were desorbed in ethyl acetate and analyzed using gas chromatography–flame. The study area is surrounded
by Aghajari Formation dominated by silt and clay sediments and the Bakhtiari Formation dominated by sand and gravel. Existence
of these formations affects the aquifer sediments and the hydrogeological properties. In the study area, the sediments grade
from gravel and sand in the north and east into silt and clay to the south and west, respectively. The topsoil in the south
of the study area contains more clay sediments. In this study, the concentration of two common herbicides, i.e., 2,4-D and
clodinafop propargyl and two pesticides, i.e., permethrin and diazinon, in the groundwater of Mian-Ab aquifer was assessed.
Chemical analysis results showed that the 2,4-D residue in the groundwater has the highest concentration (15 ppm). About 50%
of the samples have concentration values more than the maximum contamination level based on EPA drinking standard. The pesticides
concentrations decrease from the north to the south of the study area. Pesticides influx to the groundwater in the south of
the area is prevented or diminished due to the specific geological situation and soil type. Distribution pattern of population
centers, which increase to the north of the study area, and the role of groundwater as the main source of drinking water are
two important issues that must be considered in management of pesticides use in the area. 相似文献
170.
Ocean Dynamics - Third-generation models employ a host of parameterization schemes to consider the input wind forcing and the wave energy dissipation under different physical settings and... 相似文献