University of Esfahan

Eşfahān, Iran

University of Esfahan

Eşfahān, Iran
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Abbasy S.,University of Zanjan | Abbasi M.,University of Zanjan | Asgari J.,University of Esfahan | Ghods A.,Institute for Advanced Studies in Basic Sciences
Meteorological Applications | Year: 2017

Meteorological investigations using the global positioning system (GPS) are based on expensive permanent networks and they are not developed globally on the Earth. In this study it is confirmed that single station GPS meteorology is feasible where there is no possibility for development of a sophisticated dense GPS network. Since 1 January 2011 a GPS station has been installed in the Institute for Advanced Studies in Basic Sciences in the province of Zanjan, Iran, where upper air meteorological data are not available. The GPS data were processed in order to estimate the zenith total delay (ZTD) of GPS signals due to the troposphere. The estimated ZTD was then transformed to precipitable water vapour (PWV) using the ERA-Interim globally available humidity and temperature vertical profiles. Three kinds of validation were applied to the estimated PWV and all of them reasonably proved the validity of the GPS results: (1) the measured surface water vapour pressure and dew point temperature show 87.8 and 86.6% correlation respectively with the estimated PWV; (2) the PWV measured using radiosondes in three neighbouring cities of Zanjan (Tabriz, Tehran and Kermanshah) with nearly the same climatic regime show 81.1, 71.7 and 66.4% correlation respectively with the GPS PWV time series, and (3) the global reanalysis datasets for Zanjan show 89.2% correlation with the GPS results. These validations indicate that, in the absence of permanent GPS networks, if proper data processing strategies are adopted the low cost single station GPS meteorology can be considered as a possibility for meteorological monitoring. © 2017 Royal Meteorological Society

Sabziparvar A.A.,Bu - Ali Sina University | Parandeh A.,Meteorological Research Center | Lashkari H.,Shahid Beheshti University | Yazdanpanah H.,University of Esfahan
Natural Hazards and Earth System Science | Year: 2010

Flood is known as one of the most distractive natural disaster worldwide. Therefore, its prediction is of great importance from the socio-economical point of view. Despite the great improvement in computational techniques and numerical weather prediction approaches, so far, in Iran, an acceptable flood prediction method has not yet been introduced. The main aim of this study is to recognize and classify the patterns of synoptic systems leading to torrential rainfalls in a watershed basin located in south-west of Iran. In this research, 20 major floods characterized by high rainfall intensities and severe damage were selected. The pattern, extension, and the direction of movement of the selected synoptic maps from surface to 500 hPa pressure levels were identified. Furthermore, the position of cyclones, anti-cyclones and mid-level trough lines were carefully tracked and classified into different groups. The results show that the major severe floods occurring in Dalaki watershed river basin are mainly influenced by strengthening of the center of Sudan heat low (SHL) and the coincidence moisture feeding by the Indian Ocean and Mediterranean Sea. It was found that simultaneous merging of the SHL system and Mediterranean frontal system would intensify the flood intensities over the basin. The mean positions of high pressures, low pressures, the Red Sea trough lines and 1015 hPa isobars of the major floods are also discussed. © 2010 Author(s).

Pour M.G.,Golestan University | Popov L.E.,National Museum of Wales | Hosseini M.,18 Hajarol Asvadi Alley | Adhamian A.,Petroleum Engineering and Development Company | Yazdi M.,University of Esfahan
Memoirs of the Association of Australasian Palaeontologists | Year: 2013

An asteropygine trilobite and brachiopod association, including new species Heliopyge sohensis and Leptagonia? lakhalensis, is described from the Soh area, north of Esfahan, Iran. The co-occurrence of Douvillina and Neocalmonia aff. quadricosta Pillet indicates a Frasnian age for the trilobite-bearing horizon. The underlying units of limestone (Bahram Formation equivalent) contain a diverse conodont assemblage characteristic of the upper Givetian hemiansatus to ansatus biozones. The faunal assemblage from Soh has an affinity to the contemporaneous faunas of Afghanistan, Chitral in Northern Pakistan and the eastern Pamir.

Heydari E.,Jackson State University | Arzani N.,Payame Noor University | Safaei M.,University of Esfahan | Hassanzadeh J.,California Institute of Technology
Global and Planetary Change | Year: 2013

This investigation focuses on the original mineralogy of Wuchiapingian (Late Permian) to Induan (Early Triassic) strata of the Shahreza section of Iran to understand changes in marine carbonate system during this transition. Aragonitic carbonates precipitated during the early part of the Wuchiapingian, gradually changing to calcite during the middle part of the Wuchiapingian and continuing through the Changhsingian. Carbonate precipitation ceased during the latest Changhsingian at the end-Permian Event Horizon (EH). A sharp reversal back to aragonite precipitation occurred in the Early Triassic. These changes are interpreted as the ocean's response to a changing climate. This study proposes three types of seawater for the Late Permian to Early Triassic interval. Normal (Anahita-type) seawater during the Late Permian was hospitable to life and supported a highly active carbonate factory. Acidic (Jahi-type) seawater during the PTB transition was acidic and hostile to life, slowing or halting carbonate production. Alkaline (Amordad-type) seawater during the Early Triassic was life-nurturing and supported an active carbonate factory. It sustained life until a normal (Anahita-type) seawater could be re-established. © 2012 Elsevier B.V.

Balling R.C.,Arizona State University | Kiany M.S.K.,University of Esfahan | Roy S.S.,University of Miami
Atmospheric Research | Year: 2016

We analyzed spatial and temporal patterns in temperature extremes from 31 stations located throughout Iran for the period 1961 to 2010. As with many other parts of the globe, we found that the number of days (a) with high maximum temperatures was rising, (b) with high minimum temperatures was rising, and (c) with low minimum temperatures was declining; all of these trends were statistically significant at the 0.05 level of confidence. Population records from 1956 to 2011 at the station locations allowed us to reveal that the rate of human population growth was positively related to the increase in the number of days with high maximum temperatures and negatively related to days with low maximum temperatures. Our research shows a number of identifiable anthropogenic signals in the temperature records from Iran, but unlike most other studies, the signals are stronger with indices related to maximum, not minimum, temperatures. © 2015 Elsevier B.V.

Senowbari-Daryan B.,Friedrich - Alexander - University, Erlangen - Nuremberg | Rashidi K.,Payame Noor University | Torabi H.,University of Esfahan
Facies | Year: 2010

The following paper describes the foraminiferal fauna and associated faunal assemblages of the bedded and reef carbonates of the Upper Triassic (most probably Rhaetian) Nayband Formation, which are exposed in a section south of the small town of Bagher-Abad, northeast of Esfahan. Foraminifers are extremely rare in sponge- or coraldominated bioconstructions and in the bedded carbonates of the Nayband Formation in central Iran. Some carbonate beds are composed of bioclastic wackstone/packstone. These are exposed in the solenoporacean horizon at the uppermost part of the section. Here, the aulotortid- and trocholinid-type foraminifers are relatively abundant. The following foraminiferal taxa with different abundances were found within the carbonates of the investigated section: Trocholina umbo Frentzen, T. turris Frentzen, T. gracilis Blau, Aulotortustumidus (Kristan-Tollmann), Aulotortustenuis (Kristan), Aulotortus friedli (Kristan-Tollmann), Coronipora etrusca (Pirini), Semiinvoluta clari Kristan, Turrispirillina? licia variabilis Blau, Galeanella? laticarinata Al-Shaibani, Carter and Zaninetti, Ophthalmidium sp., Agathammina sp., "Sigmoilina" schaeferae Zaninetti, Planiinvoluta carinata Leischner, Planiinvoluta sp., Nubecularia sp., Endothyra sp., Paeolituonella sp. and some sessile agglutinated and nodosariid types. All mentioned taxa are very rare, except the involutinid and trocholinid types. The following species are described as new: Trocholina blaui nov. sp., Spirilina? iranica nov. sp., and Coronipora serraforma nov. sp. Trocholina blaui is usually attached to solenoporacean thalli. Four foraminiferal associations, which are named after the occurrence of the abundant species, were distinguished as Aulotortus tumidus association, Aulotortus friedli association, Trocholina umbo association, and Trocholina blaui association. Aulotortid types and Trocholina umbo were found within the bioclastic wackstone/packstone carbonates. Trocholina blaui is abundant in solenoporacean framestones. The foraminiferal association of investigated carbonates contains a mixed fauna, known from Upper Triassic-Liassic in the Tethyan realm. Carbonates of the whole investigated section are dated-due to occurrence of the genus Aulotortus, with species A. tumidus (Kristan-Tollmann), A. tenuis (Kristan), and A. friedli (Kristan-Tollmann)-as Upper Triassic (most probably Rhaetian). The "typical" foraminifers occurring in the reef biotopes in the northwestern Tethys are either missing or extremely rare in the Iranian bioconstructions. © 2010 Springer-Verlag.

Nikbakht P.,University of Esfahan | Mahdavi M.,University of Esfahan
2015 7th Conference on Information and Knowledge Technology, IKT 2015 | Year: 2015

Digital watermarking is widely used to verify the authenticity or integrity of multimedia contents, such as images and videos. In the last few years, a well-known numerical tool called singular value decomposition (SVD) has received much attention from the watermarking community. Designers of SVD-based schemes usually use dewatermarking tools such as Stirmark to prove the robustness of their schemes. Although, these tools are valuable but their attacks usually reduce the quality of watermarked images. On the other hand, there is another group of attacks in which the attacker needs to know the watermarking algorithm to perform the attack. In this paper, an attack in this group has been designed to remove the watermark from a specific SVD-based watermarking scheme [1]. The attack tries to change the exact space where watermark has been embedded. The experiments show our attack makes fewer changes to remove embedded watermark than other distortions available in Stirmark, so the quality of attacked image is better than processed image by using Stirmark in terms of PSNR. © 2015 IEEE.

Mokhtaripour M.,University of Esfahan
World Academy of Science, Engineering and Technology | Year: 2011

Security issue and the importance of the function of police to provide practical and psychological contexts in the community has been the main topics among researchers, police and security circles and this subject require to review and analysis mechanisms within the police and its interaction with other parts of the system for providing community safety. This paper examine national and social security in the Internet.

Abedi M.R.,University of Esfahan | Vostanis P.,University of Leicester
European Child and Adolescent Psychiatry | Year: 2010

Previous research has provided evidence on the effectiveness of CBT in the symptomatic improvement of children with obsessive-compulsive disorders. There is also increasing recognition of the importance of involving parents and families in treatment. The aim of this study was to evaluate the short-term effectiveness of such an intervention that promoted family strengths [(quality of life therapy (QoLT)] for mothers of children with obsessive- compulsive disorders (OCD). The sample consisted of 40 children with OCD and their mothers, who had been referred to clinics in Esfahan city in Iran. Mothers were randomly allocated to an experimental (QoLT) and waiting list control group. Mothers participated in eight QoLT group sessions over 4 weeks. QoLT incorporated CBT techniques in managing OCD symptoms. Measures were completed pre- and post-intervention by both groups. Children completed the Yale-Brown obsession compulsion scale for Children, the Revised children's manifest anxiety scale, and the brief multidimensional student's life satisfaction scale; mothers completed the quality of life inventory (QoLI). QoLT was associated with decrease in OCD and anxiety symptoms and increase in children's satisfaction in the global, family and environment domains, as well as with increased QoLI scores in their mothers. Parenting interventions like QoLT can complement individual modalities such as CBT in the presence of familyrelated difficulties. This can be particularly applicable in countries and settings with limited resources and high stigma of child mental health problems. © The Author(s) 2010.

Nikbakht P.,University of Esfahan | Mahdavi M.,University of Esfahan
2015 5th International Conference on Computer and Knowledge Engineering, ICCKE 2015 | Year: 2015

Digital watermarking has become an important technique for copyright protection of multimedia contents. In recent years, Singular Value Decomposition (SVD) has been used as a valuable transform technique for robust digital watermarking. Designers mostly use dewatermarking tools such as Stirmark to prove the robustness of watermarking schemes. Distortions available in these tools usually degrade the quality of images and resistance against these distortions does not imply the scheme is secure. Despite of distortions, there are many types of attacks which violate security. There is a kind of attack in which the attacker needs to know the watermarking algorithm to perform the attack. In this paper, two attacks of this kind have been designed against two specific non-blind SVD-based watermarking schemes. These attacks try to subtract the added watermark or change the exact spaces where watermarks have been added. The experiments show our attacks make fewer changes to remove embedded watermarks than other distortions available in Stirmark, so the quality of attacked images is better than processed images by using Stirmark in terms of PSNR. © 2015 IEEE.

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