Nowadays, designing hydraulic structures for flood damage mitigation has a significant importance in water engineering. One of the necessary parameters for the design of flood control measures is the probable maximum 24-hour precipitation in a 1000-year return period. This research was done using Jiroft Halilrud watershed data to evaluate Hershfild methods. Firstly, the maximum annual precipitation data series were used to do a frequency analysis using linear moments method to determine the maximum precipitation in 1000-year return period. Then this parameter was determined using the Hershfild method. The results showed a good agreement between the two methods according to correlation coefficient (0.87). The results of this research can be used for the monitoring system of the region.

Natural disasters threatening and endangering human communities has resulted in the study and research of such disasters through the related sciences and present methods of forecasting their behavior with time and place and also from a qualification and quantity viewpoint. To this end, numerous methods for the determination of the maximum flood in various return periods has been made available which can be refered to as flood frequency analysis methods. One of these methods is the regional flood frequency analysis in which instead of using the data from a single station, it considers the data and characteristics of a group of similar stations. In the case under the research this method uses L-Moments and Index Flood in North, Razavi and South Khorasan water basins and MATLAB software. Maximum annual flood statistics were used from 68 Hydrometric stations with minimum and maximum statistical periods of 6 and 39 years. Using Cluster analysis the region under study was divided to 7 partitions. Discordance test has conducted and only one station in region C was found as discordance station. Because of knowing the homogeneity of the regions, the parameter of Kappa distribution were estimated and with using the simulation method of Monte Carlo with 500 times, the homogeneity measure was tested in 7 regions. Using homogeneity test all regions was found homogen. Using goodness-of-fit measure z and Kolmogrove-Smirnov the Log normal 3 parameters distribution were selected for two regions of A and B, GEV for C, Generalized Pareto for D and E, Generalized logistic for F and Pearson III for G. Besides, GEV distribution was found appropriate for all of the regions, only their parameters are different in any regions. For estimating of index flood a logarithmic model has found for each region with 4 variables of area, height, average slop and form factor. Using of these models, the index flood can be estimated in each region and it can be used for standardize the statistics of maximum flood values.

For estimation of statistical distributions function parameters different methods existed that the most prevailing and the oldest is central moment methods. The use of L - moment has been adopted now only for a years and its application is in primary stages in our country. In this research has done comparison between ordinary moment and new rations of L - moment until clear application of this method in order to estimation of maximum, mean and minimum discharges in north area of country.According to results of this research for annual maximum discharge in LN2 and LN3 distribution, moment method and in P3 and LP3 distribution linear moment method have been suitable distinguish and in Gumbel distribution, moment method and linear moment method equal have been suitable distinguish. For annual peak discharge in LN2and LN3and P3 distribution, moment method, in LP3 and Gumbel distribution linear moment method have been suitable distinguish in all stations. In the case of mean and minimum discharges in all distribution and stations, linear moment method have been suitable distinguish.

This research provides a detailed assessment of the progressive collapse susceptibility of reinforced concrete (RC) moment-resisting frames through the Alternate Load Path (ALP) method implemented using linear static analysis. The analytical framework follows UFC 4-023-03 and ASCE 7 provisions, employing dynamic load increase factors and material modification coefficients to account for the effects of dynamic response and material nonlinearity. A ten-story RC building, designed in accordance with the Iranian Seismic Code (Standard 2800) and the National Building Regulations (Part 9), was modeled to evaluate the influence of column location and story level on collapse propagation. Corner, exterior, and interior columns were removed at the first, sixth, and roof stories to simulate a comprehensive set of abnormal loading scenarios. Structural performance was quantified using vertical deformation at the removed-column location and demand-to-capacity ratios (D/C) for adjoining beams and columns. The results demonstrate that corner-column loss governs the response, generating the highest vertical displacements and the most critical D/C demands. Column removal at upper stories amplifies progressive-collapse potential due to reduced redundancy and fewer effective load-redistribution paths. While columns generally retained sufficient post-redistribution capacity, beams adjacent to the removed column exhibited significant overstress, indicating local failure susceptibility. Overall, the findings reveal that RC moment frames-even when designed in full compliance with contemporary seismic and structural provisions, may lack adequate robustness against localized member loss. These outcomes underscore the necessity of integrating progressive collapse assessment into design practice and highlight the importance of redundancy, continuity, and load-path optimization in achieving resilient structural systems.

In this paper, we considered a Bayesian hierarchical method using the hyper product inverse moment prior in the ultrahigh-dimensional generalized linear model (UDGLM), that was useful in the Bayesian variable selection. We showed the posterior probabilities of the true model converge to 1 as the sample size increases. For computing the posterior probabilities, we implemented the Laplace approximation. The Simpli ed Shotgun Stochastic Search with Screening (S5) procedure for generalized linear model was suggested for exploring the posterior space. Simulation studies and real data analysis using the Bayesian ultrahigh-dimensional generalized linear model indicate that the proposed method had better performance than the previous models. Keywords: Ultrahigh dimensional; Nonlocal prior; Optimal

The increasing exploitation of groundwater reserves and consequently the drop in the water level and reduction of the reserves have seriously caught the attention of officials and planners to the integrated management of groundwater and surface water resources. The evaluation and management of water resources are considered as one of the key factors in comprehensive development. Boein Aquifer in Isfahan Province located in the Gavkhooni Basin is studied in this study. The Standard Precipitation Index (SPI), Reclamation Drought Index (RDI) and Groundwater Standard Index (GRI) in the time scales of three, six, 12, 24 and 48 months and Cultivated Land Index (CLI) in annual time scale are calculated. Results showed that the highest correlation between the SPI and GRI is in 18 and 24 months' time scale, and there is a delay of 1.5 to 2 years between these two droughts. Contrary to the results of some references, the correlation between meteorological drought index and GRI does not always increase with increasing the time scale. A synchronic study of the SPI, GRI and CLI shows a large difference between the SRI and the other two indicators in 2004-2008 periods that may be related to the poor management of the region. However, more close values obtained for these three indices in the recent years mainly due to the better management of water consumption by relevant organizations. To determine homogeneous drought regions, different combinations of temporal and spatial scales were used by creating 39 different scenarios and running 390,000 simulations. None of the heterogeneity measures were met in 90% of cases. This indicated that the linear moment technique is not a suitable method for determining homogeneous arid regions of groundwater probably due to the non-random data. Therefore, the linear moment technique will be more useful if the data is random.

The Rainfall Depth-Duration-Frequency (DDF) relationship is an important concept in hydrology, which is of important in engineering projects as well as in water structures. In this study twenty four recording rain gage stations (from Ministry of Energy) in Khorasan provinces were considered. The region was divided in two homogeneous sections (A and B with 8 and 16 stations, respectively), by considering different parameters of mean annual precipitation (MAP), longitude, and latitude by using cluster analysis. The homogeneity of these regions were confirmed by linear moment theories. Generalized Extreme Value (GEV) were fitted to the short duration rainfalls, regional depth- duration, and depth- frequency, which were established for each region. The equations were combined to assign regional DDF relationships. The derived equations are functions of duration, frequency, and a key parameter; 10- year, 60-minute rainfall were showed a maximum error of 19%. which are able to determine the depth of rainfall in the duration of 5 to 60 minute and the frequency of 2 to 100 years. The differences of these results were negligible, as compared with the Gumble distribution.