Showing 5 results for Metric
Saeed Zanganeh,
Volume 15, Issue 38 (4-2015)
Abstract
Abstract
Urban form can be affected by diverse factors in different times. Socio- economic, political and physical factors are among the main contributors. So, one of the most important challenges of urban planners is measuring and identifying urban development pattern in order to direct and strengthen it to sustainable pattern and right direction. The case study of the present paper is the city of Yazd, a middle-sized city in the center of Iran, and the studied years are 1975, 1987, 2000 and 2010. To achieve the main objective of the paper, measuring Yazd growth and expansion by spatial metrics, it has used remote sensing data and satellite imageries and ArcGIS software. The conclusion revealed that in four periods of study, complexity or irregularity of the urban patch shapes has increased, centrality or average distance of the dispersed parts to the city center has decreased, compactness or the number and area of patches their distance from each other has decreased, porosity or ratio of open space has increased and finally population density of city has decreased in a large amount. Therefore, all perimeters show that the temporal - spatial form of Yazd has moved from compact to sprawl. Due to many undesired impacts of urban sprawl, urban planners and authorities are required to use adherent techniques and policies to control urban sprawl and to direct it toward more sustainable directions.
Mehdi Asadi, Khalil Valizadeh Khamran, Mohammad Baaghdeh, Hamed Adab,
Volume 20, Issue 59 (12-2020)
Abstract
Using Landsat satellite images taken in 2015/08/10 and also SEBAL and metric methods, surface albedo amounts for various land uses in the northern half of the Ardabil province was estimated. ENVI4.8 and ArcGIS10.3 softwares were also used. To determine the type of usage of different levels, the maximum likelihood algorithm classification method was used with Kappa coefficient of 86.14% and overall accuracy of 92.63%. The results indicated that the water levels with the mean value of 0.93 and 0.414, respectively, had the least amount of albedo in SEBAL and METRIC methods. Also, based on the results obtained from SEBAL and METRIC methods the city albedo is about 0.313 and 0.278 respectively. These values are the highest levels of albedo among Land use levels. In this study, the amount of albedo in rangelands was determined to be between 0.183 to 0.266 in the SEBAL method and between 0.237 and 0.265 in METRIC method. The amount of albedo was also examined in agricultural (0.240 based on SEBAL method and 0.247 based on METRIC method) and forest lands (0.149 based on SEBAL method and 0.225 based on METRIC method). Finally, according to the results of Albedo values based on SEBAL and METRIC methods, it was concluded that due to the difference in net energy received at different levels, it is possible to estimate the level of albedo levels, which is very effective in estimating evapotranspiration by remote sensing methods.
Mansor Parvin,
Volume 22, Issue 64 (3-2022)
Abstract
Semi-arid watersheds are sensitive to soil erosion process and suffer considerable losses each year. Morphometric studies are an important method for identifying susceptible erosion zones and are a prerequisite for assessing erosion patterns in watersheds.The semi-arid Kamyaran basin is at risk of soil erosion due to lithological diversity, varied geomorphology, rugged topography and the nature-based livelihoods of its inhabitants and determination of soil erosion potential of this basin is essential for scientific management and sustainable development. The purpose of this study is to prioritize soil erosion potential in the Kamyaran basin. Methodologically, this research is based on WSA and averaging methods based on the calculation and ranking of morphometric parameters. The results showed that according to WSA methods and averaging 53.63% and 75.91% of Kamyaran catchment area, respectively, are located in areas with high soil erosion potential and require protection plans. The WSA method has better performance for prioritizing soil erosion studies due to different morphometric parameters and how to calculate it accurately. Sub-basins located in the northern areas of the Kamyaran Basin have high potential for soil erosion and sub-basins in the southern areas have low soil erosion potential. In general, the amount of soil erosion potential in Kamyaran basins is affected by the lithological and geomorphological conditions of the basins and the parameters related to infiltration have the most influence on the extent of soil erosion potential in the basins.
Sayyd Morovat Eftekhari,
Volume 24, Issue 74 (9-2024)
Abstract
One of the consequences of the earthquake can be changes in the elevation levels of the unevenness in the area of occurrence. These changes at the level of the region will not be the same and the amount will be different under the influence of several factors such as: earthquake intensity, landforms, geo-material, and structure geological... The purpose of this research is to measure the geomorphometric changes caused by the earthquake of 17th February 2021 at the level of Dana County using the radar technique differential SAR Interferometry. To achieve this goal, taking into account the appropriate coverage and measurement accuracy of the Sentinel 1 radar satellite images from two image scenes related to the earthquake area for the dates before (2021.02.08) and after the earthquake (2021.02.20) from the organization's website. European Space Agency (ESA) was received, after performing the process and data analysis Differential Synthetic Aperture Radar Interferometry (D-InSAR), it was found that after the earthquake dated 2021,02,17, a part of the studied area was affected by positive elevation changes with a rise of 0.11 cm and Negative changes of -0.6 cm subsidence have been encountered. These positive changes (uplift) are more noticeable near the epicenter of the earthquake in the east of Dena, and the negative changes (subsidence) are quite evident with the Syncline Valley on which Khorasan Rivers is located. And in dealing with the faults, changing the geological structure, geo-material of the region, it has a special irregularity.
Miss Tara Heidari Orojloo, Dr Afshin Afshin Ghorbani Param, Dr Faramrz Hasanpour,
Volume 25, Issue 79 (12-2025)
Abstract
The climatic conditions of various regions in Iran are critical parameters in the design and provision of thermal comfort within residential architecture. This study aims to develop appropriate climate-responsive design models for Shiraz, grounded in thermal comfort indicators. The research employs a descriptive-analytical methodology, utilizing advanced modeling software, specifically the Grasshopper plugin, for simulation purposes. Climatic data for the city of Shiraz has been extracted using the Ladybug plugin, with the relevant EPW file incorporated into the analysis. This data was then employed to simulate climate tables, generate diagrams of flowerbeds, and determine optimal building orientations, in addition to creating psychrometric diagrams to identify the most effective design solutions aligned with the local climate. The findings indicate that Shiraz falls within the climate comfort zone during the winter and spring months, notably in February, March, and April. However, it is important to note that the temperature during these months, with the exception of April 13-16, often exceeds the comfort range. Consequently, it is recommended to position the majority of windows on the southern façade and to incorporate auxiliary heating systems. Conversely, during the months of June, July, August, and September, temperatures surpass the comfort level; thus, the integration of materials with high thermal mass, appropriate shading devices, and the utilization of evaporative cooling systems are essential to alleviate internal conditions and maintain indoor comfort levels.
