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211.
A systematic monitoring program was implemented in 1999 to evaluate the temporal changes in the physical properties and chemical composition of water from the Shahrood Qanat, which provides 30% of Shahroods municipal water needs. A qanat is a near-horizontal gallery which yields water by gravity. The results show that the physical properties, in contrast to the concentration of ions, are in an almost steady state condition and the slight variations are due to the travel time of water in the qanat gallery, the mixing of qanat water, the seasonal temperature fluctuation, and the likely unavoidable errors associated with long-term monitoring. They also show that severe drought during the past nine years has not yet affected the groundwater quality. The TDS of the qanat water is relatively low and the water is of the calcium-bicarbonate type. However, the above average concentrations of nitrate (14.9 mg/L) and phosphate (0.105 mg/L) may reflect the impact of the excessive use of fertilizers in the capture zone of the qanat. High Ca, Mg, pH, and a higher-than-recommended hardness value reflect the influence of carbonate-rock formations on the groundwater composition. The study shows that systematic monitoring is required to identify the erroneous data, to optimize the monitoring program and to characterize the water quality trend.
Resumen En 1999 fue implementado un programa intensivo y sistemático de monitoreo, para evaluar los cambios temporales en las propiedades físicas y en la composición química de la galería para captar agua tipo kanat de Shahrood. Los resultados muestran que las propiedades físicas se encuentran casi en una condición estacionaria y que las poco significativas y tenues variaciones, se deben al tiempo de viaje del agua en la galería kanat, a la mezcla del agua del kanat, a la fluctuación estacional de temperaturas y a los probables e inevitables errores asociados con el monitoreo de largo plazo. Con base en los resultados del presente estudio se determinó que las sequías más severas, ocurridas durante los últimos nueve años, no han afectado aún la calidad del agua subterránea. El contenido de TDS en el agua del kanat es relativamente bajo y el agua es del tipo bicarbonatada-calcica. Sin embargo las concentraciones por encima del promedio de nitratos (14.5 mg/L) y fosfatos (0.105 mg/L), reflejan el impacto del uso excesivo de fertilizantes en la zona de captura del kanat, sobre la calidad del agua subterránea. Los valores altos de Ca, Mg, pH y dureza reflejan la influencia de las formaciones carbonatadas sobre la composición del agua subterránea. El estudio muestra que se necesita un monitoreo sistemático para identificar los datos erróneos, lo mismo que para optimizar el programa de monitoreo y para predecir potenciales cambios futuros en la calidad del agua.

Résumé A partir de 1999 on a mis au point un programme de surveillance systématique pour évaluer les changements temporelle des propriétés physiques et chimiques de leau du captage de type qanat de Shahrood. Il a résulté que les propriétés physiques sont presque stationnaires, les variations insignifiants ayant dues au temps de transfert et au mélange de leau dans la galerie, aux variations saisonnières de la température ainsi quaux erreurs inévitables associées à une surveillance à long terme. Cet étude a montré aussi que la qualité de leau na pas été influencée par la période de neuf ans de sécheresse. Le résidu à sec de leau présente des variations assez faibles et leau appartient à la catégorie de Calcium-Bicarbonate. Tout de même les valeurs moyennes des concentrations en nitrates (14.5 mg/L) et en phosphates (0.105 mg/L) mettent en évidence limpact de lutilisation excessive des engrains dans les zones de captage de qanat de Shahrood. Les valeurs élevées de la concentrations en Ca et Mg, du pH et le fait que la dureté dépasse les limites recommandées mettent en évidence linfluence des carbonates de la matrice sur la composition des eaux souterraines. Cet étude montre aussi quil est nécessaire une surveillance systématique affin didentifier les données erronées, doptimiser le programme de monitoring et destimer les changements potentielles de la qualité de leau.
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213.
Current land administration systems mainly use 2D plans to define and secure ownership rights associated with properties in high‐rise buildings. These 2D plans may not effectively communicate and manage the spatial complexity associated with multi‐layered and stacked properties in such buildings; additionally, multiple pages of plans (representing sections of the building) are required to represent all ownership boundaries. In response, land administration organizations have been investigating a 3D digital approach to managing information about ownership rights in high‐rise building structures. In this article, Building Information Modeling (BIM) is proposed as a feasible approach for managing land and property information in high‐rise buildings. BIM provides a collaborative, digital and intelligent 3D data environment for managing building information throughout the lifecycle of buildings. However, there is currently no capacity in BIM for recording and representing information about ownership and boundaries of properties, which is core land administration information. Therefore, this article proposes an extension to the BIM standard, which is implemented in a prototype BIM model of a complex building to showcase the potential capability of using BIM for high‐rise land administration and for modeling 3D ownership rights.  相似文献   
214.
Radwan  A.  El Fakharani  A.  Abbas  H.  Younis  M. H.  Emam  A.  Fawzy  Sh. 《Geotectonics》2021,55(1):94-111
Geotectonics - Poly-deformed late-Proterozoic metamorphic domains covering Um Ashira area at the western segment of Wadi Allaqi shear zone, South Eastern Desert of Egypt, show evidences of inverted...  相似文献   
215.
Bahrami  Yousef  Hassani  Hossein  Maghsoudi  Abbas 《GeoJournal》2021,86(4):1797-1816
GeoJournal - Landslides are natural destructive phenomena that can cause great damage to property and life loss. One of the fundamental proceedings to reduce the possible damage is identifying...  相似文献   
216.
Acta Geochimica - One of the essential tasks accelerate the decision-making process in mineral exploration projects is ranking anomalous areas. In this study, we used fourteen geologic maps (at...  相似文献   
217.
Various methods have been used to secure the certainty of significant relations among the sunspot cycles and some of the terrestrial climate parameters such as temperature, rainfall, and ENSO. This study investigates the behavior of ENSO cycles and mean monthly sunspot cycles. Sunspot cycles range from 1755 to 2016 whereas, ENSO cycles range from 1866 to 2012. In this regard, the appropriateness of distributions is investigated with the help of Kolmogorov-Smirnov D, Anderson-Darling, and chi-square tests. It is found that most of the sunspot cycle follows generalized Pareto distribution whereas, generalized extreme value distribution was found appropriate for ENSO cycles. Probability distribution is used to analyze the behavior of each sunspot cycle and ENSO cycle separately. Probability distribution indicates the tail behavior of each cycle; tail explored correlation cycles. Furthermore, self-similar and self-affine fractal dimension methods are used to compute Hurst exponents to determine the persistency of the available data. Fractal dimension has an ability to study the complexity involved in sunspot and ENSO cycles. The fractal dimension and Hurst exponent describe persistency (smoothness) and complexity of data. Hurst exponent measures long-term behavior of time series, making it more helpful for forecasting. This is the measure of regularity or irregularity (chaos) of the time function in the form of their persistency or anti-persistency, respectively. Hurst exponents are computed using rescaled range analysis method and box counting methods. Both these methods are suitable for long-term forecasting. The results of this study confirm that during the period 1980–2000, ENSO cycles were very active. Simultaneously, ENSO was active for the periods 1982–1983, 1986–1987, 1991–1993, 1994–1995, and 1997–1998; these periods include two strongest periods of the century viz., 1982–1983 and 1997–1998. Sunspot cycles and ENSO cycles both were found to be persistent. Self-similar fractal dimensions exhibited a better persistency and a better correlation as compared to self-affine fractal dimension. This research is a part of a larger research project investigating the correlation of sunspot cycles and ENSO cycles, and the influence of ENSO cycles on variations of the local climatic parameters which in turn depends on solar activity changes.  相似文献   
218.
Block-flexure is the most common type of toppling failure in rock slopes. In this case, some rock blocks fail due to tensile bending stresses and some overturn under their own weights. In this paper, first, a literature review of toppling failures is summarized. Then, a theoretical model is proposed for rock slopes with a potential for block-flexure toppling instability. Next, a new analytical approach is presented for the stability analysis of such slopes. Finally, a special computer code is developed for a quick stability assessment of the failures based on the proposed method. This code receives the rock slope parameters from the user as the input data and predicts its stability, along with the corresponding factor of safety against the failure, as the output. In addition, two case studies are used for practical verification of the proposed approach and the corresponding computer code as well.  相似文献   
219.
Landfill site selection is a complex and time-consuming process, which requires evaluation of several factors where many different attributes are taken into account. Decision makers always have some difficulties in making the right decision in the multiple attribute environments. After identifying candidate sites, these sites should be ranked using decision-making methods. This study applies Chang’s fuzzy AHP-based multiple attribute decision-making (MADM) method for selection of the best site of landfills based on a set of decision criteria. The Fuzzy Analytic Hierarchy Process (FAHP) was designed to make pairwise comparisons of selected criteria by domain experts for assigning weights to the decision criteria. Analytic Hierarchy Process (AHP) is used to make pairwise comparisons and assign weights to the decision criteria. It is easier for a decision maker to describe a value for an alternative by using linguistic terms and fuzzy numbers. In the fuzzy-based AHP method, the rating of each alternative was described using the expression of triangular fuzzy membership functions. Once the global weights of the criteria is calculated by AHP, they are incorporated into the decision matrices composed by decision maker and passed to fuzzy-AHP method which is used to determine preference order of siting alternatives. In this study, a computer program based on the Chang’s fuzzy method was also developed in MATLAB environment for ranking and selecting the landfill site. As an example of the proposed methodology, four different hypothetical areas were chosen and implemented to demonstrate the effectiveness of the program. By using this program, the precision was improved in comparison with traditional methods and computational time required for ranking and selecting the suitable landfill site was significantly reduced.  相似文献   
220.
Dust storms loads analyses—Iraq   总被引:1,自引:1,他引:0  
The dust storms that blow over Iraq were studied from December 2008 to March 2009. The total number of studied dust storms was eight; during each dust storm, samples were collected from the cities of Baghdad, Ramadi, Kut, Basra, Najaf, Karbala, Hilla and Tikrit. The climatic elements with the dust storms types were studied. The results of dust storms analyses reflect their increase in average toward the southwestern direction (average suspended, rising, regional dust storms were 8, 10, 15 days/year, respectively). The average means annual rainfall (in mm), evaporation (in mm), temperature (in °C), and relative humidity percentage indicate that there were remarkable variations in values, with increase of the number of days/years of the dust storms reflecting the effect of the regional climatic change. The results of particle size analyses indicate the texture of most samples range from sandy clayey silt (75%) and clayey sandy silt (25%), and the average dominant grain size have a direct relationship with trajectories of dust storms. Quartz grains were 15% rounded and 85% sub-rounded. Moreover, the dust samples were analyzed and identified by using XRD analyses and Polaroid microscope. The results reflect the following minerals according to their average relative dominant, quartz 58.6%, feldspars 17.3%, and calcite 15.4%, with small amount of gypsum 5.5%. The clay minerals (chlorite, illite, montmorillonite, palygorskite, and kaolinite) were recognized. The analyses of heavy minerals percentages by using the microscope were performed. The results of pollen distribution, in descending order, were Chenopodiaceous, Graminea, Pine, Artemisia, Palmae, Olea, and Typha (reaching 79%, 69%, 63%, 53%, 17%, 9%, and 7% of the counted pollen grains, respectively). The results of microorganisms (i.e., isolated bacteria and fungi), in descending order, were the gram-positive Bacillus species (42.9%), Aspergillus species plus Candida albicans (13.8%), and (8.4%), the gram-negative rods, Escherichia coli (9.5%), the gram-positive Cocci streptococcus pneumonia (6.7%), then the gram-negative rod Enterobacter cloacae (4.3%), Staphylococcus epidermidis, and Staphylococcus (3.9%) and (1.9%). The remaining Gram-negative microorganisms were Pseudomonas aeruginosa (2.7%). Regarding the viral etiology, there is no viral isolate among the work results. The allergens commonly associated with dust storms include fungal spores, plant and grass pollens, and organic detritus represent agricultural area pollen grains.  相似文献   
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