In this paper, the applicability of Euler's homogenous equation method in detecting gravity anomalies from gravity or microgravity data is addressed. The stability of Euler solutions with respect to the window size, window position and choice of the structural index value (defining the anomaly attenuation rate) is analyzed and demonstrated using synthetic microgravity data created for different anomaly models. The analysis reveals that the optimum window size required to obtain the best solutions is a function of the source Depth. The horizontal location parameters can be determined correctly if the window is located in the region of high derivatives regardless the assigned structural index v. Meanwhile, Depth solution is linearly dependent on the structural index and incorrect choice of structural index leads to significant error in the estimated Depth.

Spatial distribution of snow reserves, in order to more accurately estimate the runoff from their understanding of the importance of water is snow. Spatial distribution of snow Depth required to achieve the observational data and the compressed scale, be done. However, due to practical limitations, collect information, particularly on the scale, it is difficult and sometimes impossible. Methods can not measure the Depth of snow in places, and also to estimate the extent of their use in this regard is essential. The study a range an area of 16 acres in the watershed Taft called the Skhvyd and using 216 data deep snow, using geostatistical kriging, Cokriging, Radial Basis Function (RBF) and inverse distance method (IDW) was. Variogram plotted snow Depth was measured using 216 points. Variogram obtained showed that the most appropriate variogram model is exponential, so that the variogram has a Nugget of 0.05 and a Sill of 0.533, has been, which means that there is a strong spatial structure of the data. Variogram analysis and verification statistics (RMSE) between the methods of extraction methods showed that kriging is better in snow Depth zonation. The results showed that the universal kriging, kriging methods with minimum error (11.49) and the best estimate of snow Depth in the study area.

Aerosols play an important role in the climate system of the atmosphere. These atmospheric particles are directly affected by changing radiation exposure by diffusing and absorbing different wavelengths and indirectly by changing the optical properties and the durability of the clouds, and the optical properties of the aerosols, such as aerosols optical Depth (AOD), are critical in understanding the effects of atmospheric aerosols on climate change and biogeochemical cycles. Therefore, in this research, the ability of radiation transmission model and MODIS images was evaluated to estimate the aeroeses optical Depth in Persian Gulf. MATLAB was used for images processing of the images with resolution of 500 m at 5×5 networks. The evaluation of aerosoles optical Depth data was performed by using AERONET stations with Pearson correlation, RMSE and RMSD indices. First results of the algorithm implementation showed the ability of model to simulate the aerosols optical Depth. Modeling results showed that the algorithm is correct and according to spectral reflectance data for effective radius of the LUT tables, values simulated for aerosols optical Depth. The results of evaluation showed that optical Depth values obtained from the images has significantly correlation with the measured optical Depth in AERONET stations. So that, amount of correlation calculated form 29 June 2013, 14 July 2014 and 6 October 2015 in the band of 1. 243 is 0. 96, 0. 94 and 0. 98 respectively, and for the band of 1. 643 is 0. 99, 0. 98 and 0. 98, respectively which shows a good trend between the measured data, RMSE and RMSD indices were calculated in these days less than 0. 15 and less than 0. 06, respectively. It can be concluded that simulations accuracy is appropriate in these bands.

Geothermal energy can be a good replacement for any kind of energy we use today. Estimation of curie point Depth (CPD) is one of the first steps in geothermal exploration. Spectral analysis of aeromagnetic data can provide important information about temperature distribution in Depth. In this study, we attempt to estimate the CPD using centroid method and forward modeling in northwest of Iran. The reduced-to-pole (RTP) aeromagnetic data were divided into 11 overlapping windows of the size of 100 100 km. In the centroid method, the average Depth to the top of the deepest crustal block, t Z was first computed by linear fitting to the second longest wavelength segment of the power spectrum of aeromagnetic data. Then, Depth to the centroid of the deepest crustal block, o Z was computed by linear fitting to the longest wavelength segment of power spectrum of aeromagnetic data. In forward modeling, the modelled spectra were fitted to the observed spectrum iteratively and the Depth to the top and bottom of the block was finally estimated. According to the obtained results, the CPD is shallow in the west part of the area and as a comparison of the results with the locations of hot springs in the area, we conclude that the west part of the area has a good potential for geothermal exploration. ...

Background and Objective: Meditation is commonly perceived as an alternative medicine management tool for psychological diseases such as depression and anxiety disorders. To our knowledge, there is no published study providing an index for estimating meditation's Depth from biological signals. Estimating the Depth of meditation can be useful in controlling its different levels, and it can be used as a biofeedback technique to help a person achieve the desired state of meditation. In this study, an index for meditationDepth is offered using the features of electroencephalogram and heart rate signals.Material and Methods: For this purpose, EEG signals in Fz, Cz, and Pz channels, and the heart rate time series of 25 healthy women were collected both before and during the meditations. The algorithm is suggested based on the rational alpha power of EEG signals and the time domain feature of the heart rate to estimate the Depth of meditation.Results: The analysis of biological signals using this method suggests that 22 of the 25 participants have experienced the deepest meditation state. Interestingly, 2 of the beginners as well as one expert-mediators could not reach the deepest state by following up the master mediator. These results were in line with the evaluation of the questionnaire.Conclusions: The suggested algorithm has some practical characteristics including: the option of being calibrated for each subject; not requiring high-volume calculations; and it does not take much time.

The phenomenon of resonance caused by the behavior of alluvium during an earthquake affects the occurrence of damage. This phenomenon occurs when the dominant period of alluvion is equal to the dominant period of structures (Mukhopadhyay and Bormann, 2004; Kanli et al., 2006; Kvasnička et al., 2011). Therefore, determining the dominant frequency of the soil with high certainty is particularly important and is the primary goal of this paper. The method of using microtremors to determine the site's response to earthquakes and determine the dominant frequency of the soil is of interest, and by measuring them at the ground level, information about the vibration characteristics of the soil can be obtained. (Kerh & Chu, 2002; Kianoush et al., 2023a,b; Jamshidi et al., 2024; Khoshmagham et al., 2024).Adib et al. (2015) conducted the site classification of Ardakan City in Yazd province based on the earth's natural frequency by the microtremor data. While identifying the dynamic characteristics of the earth in this area, the level of compatibility of the land classification is suitable for the studies of the site effect based on the geotechnical, geophysical, and microtremor data with the regulations of dynamic design of buildings. Similarly, Bagheri et al. (2017) emphasized the importance of denoising seismic data to improve the quality of records, which is essential for accurate interpretation. They proposed a novel method combining frequency-offset deconvolution (FXD) and decision-based median (DBM) filtering to enhance the signal-to-noise ratio (S/N) and effectively suppress random noise.Adib and others (Adib et al., 2015) classified the site effects using a fractal model based on the analysis of microtremor data, frequency amplification index, and vulnerability (k-g)) in the city of Meybod. Nogoshi and Igarashi (1970, 1971) improved, this classification and found four types of soil, including (1) hard soil and weak rock with a frequency of 6.2 to 8 Hz, (2) hard soil with a frequency of about 4.9 to 6.2 Hz, (3) relatively soft soil with a frequency of 2.4 to 4.9 Hz and (4) soft soil Soft with a frequency of less than 2.4 Hz that were separated in this city (Wahba et al., 2024; Labuta et al., 2025). Bagheri and Riahi (2016, 2018) also highlighted the effectiveness of DBM filtering in seismic data processing, demonstrating its superiority in suppressing random noise and improving S/N. This classification aligns with findings by KhodAgholi and Bagheri (2020), who introduced local least squares polynomial (LLSP) smoothing to diminish seismic random noise, thereby enhancing data quality and interpretability.The Quality of microtremor data and processing methods considerably affects the accuracy of estimating dynamic soil parameters. In this paper, an artificial sampling frequency reduction technique has been proposed for removing high-frequency perturbations from microtremor data, and a running variance method has been used to improve the automatic detection of data sections infected by local perturbations. In this method, the running variance of the signal was calculated using a sliding window. Then, the resulting variance signal was used to remove the portions of data affected by transient perturbations. The proposed methods have been applied to the data recorded for the Meybod city in the North of Yazd Province. By comparing the results of the proposed techniques and the standard methods on microtremor data in urban areas, it is clear that the proposed methods have successfully removed the effects of local transients and their redundant fluctuations such that there is no sharp amplitude variation in the residual signal. The results of the simulation confirm this claim.Additionally, the ease of parameter setting in the running variance approach makes it superior to the ratio method. Discarding the fewer amounts of contaminated data is an effective method, especially in regions with extensive noise. This paper shows that some variations in microtremor data processes could reduce the destructive effects of local transients on them and consequently improve fundamental site frequency estimation based on the spectral ratio of microtremors. Therefore, considering the low cost of this approach, microtremor analysis can be used as a primary method for initial geotechnical studies in various regions. As a result, it increases the accuracy and degree of confidence in estimating the dominant frequency based on the spectral ratio based on the microtremors data.

In this paper, the extended Euler deconvolution method is studied for interpreting magnetic and gravity anomalies. This method, overcoming some limitations of the conventional Euler deconvolution method, is utilized for simultaneous and automatic estimate of the Depth, structural index and horizontal location of potential field sources. The main limitation of the conventional Euler deconvolution method is non-linear dependency of structural index and background field; hence a simultaneous estimation of these parameter is not possible. For overcoming this problem, a value of structural index is presumed and the obtained results are evaluated according to various criteria. A wrong structural index affects the final results. In the extended Euler deconvolution, the Euler differential equation is solved for Hilbert transform of the field and its derivatives. Since the Hilbert transform of a constant value is zero, the linear dependency of structural index and background filed will be removed, and therefore the automatic calculation of structural index will be possible and the presumption of structural index is not required anymore. Moreover, since Hilbert transform has two components of x and y, the number of equations to be solved at each point is increased, and consequently the solutions are more reliable. In this paper, firstly, a background theory of the extended Euler deconvolution is discussed in detail. Then the method is applied to a magnetic anomaly produced over eighteen magnetic sphere (dipole) having different magnetic properties. Finally, the method is used for interpreting a Bouguer gravity anomaly of Noranda in Quebec province of Canada and also a magnetic anomaly of an area located near Anar city of Kerman province of Iran.