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Showing 6 results for Kriging

Professor Ghasem Azizi, , Leyla Sharifi,
Volume 17, Issue 47 (12-2017)
Abstract

Thunderstorms are major climatic events due to the significant effects and catastrophic consequences on humans and the natural environment. The researches have shown that the elevation and latitude factors are two variables that can affect the occurrence of this phenomenon. Therefore, the main aim of this study is to investigate the spatial analysis of the effects of lightning and its effects on the components such as elevation and geographic extent in Iran. Apart from this fact, firstly, the monthly data of thunderstorms occurrence in 118 synoptic stations of Iran, from 1991 to 2010 on a basis from the country's meteorological organization were obtained and GIS software was produced by the annual and seasonal maps of Iran. Then, for the spatial analysis of this climatic phenomenon, the method of landing statistics of the Kriging (Universal) method was to examine its seasonal and annual status. In order to better understand the effect of Thunder hurricanes from altitude and latitude using Curve Expert software, seasonal and annual charts, along with the correlation of each production, were analyzed. The results show that the highest annual thunderstorms occur in the northwest of Iran, and the least amount is consistent with the central and eastern parts of the country. In addition, according to seasonal analysis, although the station has the highest rate at 800 to 1,300 meters, the maximum occurrence of this phenomenon varies from 0 to 2200 meters in different seasons of the stations. The overall result shows that the factor of height is slightly correlated with the occurrence of the Thunder storm phenomenon and the highest correlation is due to the latitude factor.
Sayyed Mohammad Hosseini,
Volume 18, Issue 49 (3-2018)
Abstract

Precipitation is a climatic elements that have temporal - spatial distribution. In this research database of Global Precipitation Climatology Centre (GPCC) with a resolution 0.5×0.5 degree for 50 year is used, that was constituted with dimensions of 12800*600. Temporal data are on the columns and pixels (spatial data) located on the rows. The results show an increasing trend in spring and fall but in summer and winter precipitation trend has been decreased. The most amount of precipitation is located in the northern parts of the Black Sea and Mediterranean Sea, Southeast Asia, southern coast of the Caspian and Central Zagros Mountains. Most of Middle East (about %95) have not trend and only in some parts of Kazakhstan, Afghanistan, Pakistan ,central Iran, and areas in lower-latitude have positive trend and some East and northwest parts of Iran and some parts of Middle East also have decreasing trend of precipitation. The highest percent of area of precipitation trend gradient is 0 to 0.5.
 

Ali Asghsr Abdollahi, Moslem Ghasemi,
Volume 18, Issue 50 (3-2018)
Abstract

Analysis probative spatial data method for checking patterns spatial accidental and accidental is distribution variables spatial and correlation spatial from more usage and more important tools Analysis for is the research in the case spatial data. The aim in research, is evaluation operation methods find inside in distribution spatial land use city Kerman. That on base of methods find inside kriging ordinary with models circularly, gauss, spherical and exponential for find inside data use and with criteria error inclusive Root Mean Square) RMS( and Standard Root Mean Square) SRMS(,Mean Standard)MS(,Mean and average Mean error)ASE  (pay to evaluation veracity and exactitude. Methodology research present, descriptive – resolution with resolution spatial use software GIS. Results resolution explanatory existence pattern cluster in the land use study, administrative and commercial and pattern diffused for land use medical in the city Kerman. In between four pattern use study follow of better order. Too results research rectitude, specified pattern kriging ordinary with model gauss beater shape pattern distribution spatial use in the city Kerman

Sayad Asghari Saraskanrood, Zeynab Dolatshahi,
Volume 18, Issue 50 (3-2018)
Abstract

The purpose of this research is to evaluate the quality of wine in Khorramabad city as a major issue in public health and health management of citizens. To perform this research, data on the chemical element of 23 wells and fountains in Khorramabad County during the period of 2002 to 2013 were presented in the form of a series of elements: fluorine (F), calcium (Ca), magnesium (Mg), potassium (K) The ArcGIS software and the algebraic or deterministic internalization methods, geology, IDW method, Kriging method and splint method were used for mapping and drawing maps. To assess the chemical quality of the drinking water element, standards were used: the National Standard, World Health Organization (WHO) and the United States Environmental Organization (EPA) as an indicator of pollution. The results showed that the amount of calcium (Ca) in all seasons and in all sources is lower than the national standards (WHO) and (EPA) standards, but in some sources higher than the standard desirable standard. The amount of fluorine (F) only in the spring and summer is higher than the standard standard (EPA) in some wells, but in winter and fall in all wells and springs above the standard desirable standard (EPA) is. And the amount of potassium element (K) in any of the seasons and in any of the wells and springs is higher than the desirable and desirable national standard, WHO and EPA, as well as a handful of magnesium (Mg) in none of the water sources studied It has not been higher than the national standard, (WHO) and (EPA).

Hamid Salehi, Muhammad Motamedi, Ezatollah Mafi,
Volume 21, Issue 61 (6-2021)
Abstract

 
The basis of climatic data is measurements taken at a predetermined chronological order at air monitoring stations, so all measured values ​​of climatic elements can only be attributed to the point of measurement. Therefore, different interpolation methods can help a lot in estimating climate data in different places. The study area in this study is northeastern Iran, including the provinces of Khorasan Razavi and North Khorasan, and monthly summer temperature data were used for 21 synoptic and evaporative stations in the northeast belonging to the Meteorological Organization and the Ministry of Energy with appropriate distribution. The statistical period of 21 years (1997-1997) was considered as a common statistical period for all stations. Then, in order to compare the interpolation methods, several different methods, including ordinary kriging, spline, inverse squares and Thyssen were used by ARCGIS software. Comparing the deviations of the estimates from the measured data was evaluated by cross-validation. Then, in order to check the hypothesis of normality of the calculated errors in each interpolation method, the test thigh test was used and finally, to evaluate the best interpolation method, AHP method and Expert Choice software were used. The results showed that based on the root mean square error (RMSE) criterion, Thyssen, Kriging, inverse distance and spline methods were located, respectively. Based on the absolute maximum error criterion (MAE), the kriging method estimates the summer temperature better than other methods. According to the MBE standard, the kriging method is better than other methods and can be used for temperature interpolation. According to the set coefficients, the calculated compatibility rate is 0.03, which indicates the high accuracy of the selection of weights.
Roghayeh Delaram, Samad Fotohi, Mohsen Hamidianpoor, Morteza Salari,
Volume 24, Issue 72 (3-2024)
Abstract

The subsidence phenomenon is considered one of the most frequent hazards occurring worldwide and imposing irreparable damages every year. This phenomenon affects the ground’s surface and its layers and causes the ground deformation. It can be referred to as a morphological phenomenon that is associated with the gradual sinking of the ground and the vertical movement of materials. Among the various methods used to study the land subsidence pattern, the Differential Interferometric Synthetic Aperture Radar (DInSAR) technique has provided more accurate results. Therefore, this technique was used to investigate the subsidence rate in Mashhad plain from 2003 to 2010 and the Envisat ASAR (C-band) and Sentinel-1 ASAR (C-band) satellite images were employed during the year 2019. The results show that the highest subsidence rate of about 44 cm occurred in Qasem Abad and Kalateh-ye Barfi lands from 2008 to 2010. A subsidence rate of about 37 cm was also observed in the same area from 2007 to 2009. The interpolation results using piezometer well statistics show a decrease in groundwater levels in this area and confirm the accuracy of the results.


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