mehdi sharifzadeh

Climate change has caused changes in the frequency and magnitude of heavy rainfall, which affects the design standards of some hydrological structures (Yousef and Taha, 2015). Rainfall intensity-duration-frequency (IDF) curves are a standard tool for hydrological risk analysis and design (Mohymont, 2004; Veneziano, 2002). IDF curves show useful information about the occurrence of floods in an area and that in the future a certain amount of rainfall or a certain volume of flow will return again (Basumatary and Sil, 2018). Because the trend of severe rainfall events is expected to change in the future, this affects IDF curves, so these curves need to be updated (Srivastav et al. 2014). The need for such an understanding stems from the fact that existing drainage systems are designed to deal with past rainfall events and may not be sufficient to compensate for future rainfall characteristics (Shrestha et al. 2017). In developing countries such as Iran, the large country area as well as the shortage of rain gauge stations and/or the statistical period of the recorded data, makes it difficult to estimate IDF curves (Zamani Nouri, 2011).

Rainfall intensity-duration-frequency (IDF) curves are used to plan, design and operate water resources projects or to protect various engineering projects against floods. Curves created from past climates cannot be valid for the future climates unless they are updated with future climatic trends. The purpose of this study is to investigate the effect of climate change on IDF curves in Zahedan Synoptic Station. First, the fractal behavior of precipitation at the station was investigated and the results showed that the maximum intensity of precipitation follows the monofractal behavior. Theoretical error was calculated by the method of relative difference (RD) and the results showed that the errors are within the allowable range, then the curves are extracted for the base period (1982 to 2019) and for the return period of 2, 5, 10, 50, 100 and 200 years. Further, future precipitation data (2021 to 2055) were predicted using HadGEM2-ES general circulation model, from the CMIP5 series of models, under the RCP4.5 and RCP8.5 emission scenarios, and using LARS-WG statistical downscaling model. Based on future data, IDF curves for the future were extracted employing the fractal theory. Comparison of base and future period curves showed that the average maximum rainfall intensity in different durations and return periods increased by 22.9% under RCP4.5 scenario and decreased by 11.1% under RCP8.5 scenario.

Climate change and global warming are occurring as the most important environmental problem. It is necessary to study the trend of meteorological variables in order to detect climate change in each region. In this study, the trends of variables related to temperature (minimum, absolute minimum, maximum, absolute maximum and average) and precipitation (total precipitation, frequency of days with precipitation and maximum daily precipitation) in the annual time scale were investigated. Trend analysis was performed using non-parametric Mann-Kendall and Sen's slope estimator in 15 synoptic stations of Hormozgan, Bushehr and Sistan and Baluchestan provinces, which had complete data in the period of 1987-2019. Then, zoning maps of climate variables trends were prepared in Arc GIS software. The results showed that 3 temperature variables including: minimum, maximum and average had a significant upward trend in most of the area. The frequency of occurrence of significant upward trend related to temperature variables for each station showed that the stations of Bandar Abbas, Kish Island, Zahedan, Zabol and Iranshahr had a significant upward trend in 4 of the 5 temperature trends studied. Total rainfall in the region showed no significant trend, maximum 24-hour rainfall had a significant increasing trend only in Bushehr-Coastal Station and the frequency of days with rainfall in Bushehr-coastal had a significant decreasing trend. The results of the Sen's slope estimator showed that during 33 years, the highest rate of change of temperature variables, related to the absolute minimum, was 3.59 ° C in Kish Island. The maximum rainfall in Bushehr-coastal increased by 16.5 mm and the frequency of days with rainfall decreased by 11 days.

To report a case of adult retinoblastoma with a wrong diagnosis of melanoma. Case report: Herein, we present an adult retinoblastoma case who was misdiagnosed as melanoma in fine‑needle aspiration biopsy with intravitreal hemorrhage and later neovascular glaucoma after biopsy. The diagnosis of retinoblastoma was confirmed after enucleation. Retinoblastoma should be considered in the differential diagnosis of an intraocular mass in adults, especially when media haziness precludes adequate ophthalmoscopic visualization.

ParLeda is a software library that provides the basic primitives needed for parallel implementation of computational geometry applications. It can also be used in implementing a parallel application that uses geometric data structures. The parallel model that we use is based on a new heterogeneous parallel model named HBSP, which is based on BSP and is introduced here. ParLeda uses two main libraries that are widely used: MPI for its message passing in the parallel environment and LEDA for its data structures and computations. Dynamic load balancing and replicating C++ objects are two key features of this library. This library was implemented after a survey in research on parallel computational geometry algorithms and selection of their common primitives.