Entity

Time filter

Source Type

Bojnord, Iran

Pilehvar A.A.,University of Bojnourd
WIT Transactions on Ecology and the Environment | Year: 2010

The government in Iran, in the recent century, has played a crucial role in structural changes, particularly in cities. These changes have been made due to political division, land reforms, economical investment and performing urban development schemes in various geographical regions. After the Mashroota Revolution in 1907 and petroleum discovery in Iran, the government's political decisions and oil-centred economical development led to a change in national economy from dependency on agricultural and livestock production to oil incomes. The research results indicate that before the Islamic Revolution in 1979, the government had created functional and structural changes in the urban network and hierarchy with a capitalistic and modernistic approach and the instrumental use of oil. The changes resulted in such outcomes as racial variation, rural to urban migration, urban-regional inequality, the increasing growth and development of cities and in general urban structure sustainability. Following the Islamic Republic of Iran, the government's political decisions with an Islamic-sociological approach and socio-economical programming have influenced urban growth and development sustainability and have brought about challenges such as the reduction in urban economical efficiency, decline in urban environment quality, life quality diminution, housing crisis, etc. This paper seeks to study critically, analytically and using documental studies the contribution the government and its political decisions had in the urban structural changes in Iran in the recent century. Moreover, using documental data, the authors have presented statistical tables and diagrams, the levels of analysis and socio-economical and political structure in general and the urban structure sustainability of Iran in particular. Source


Rassi Y.,Tehran University of Medical Sciences | Abai M.R.,Tehran University of Medical Sciences | Oshaghi M.A.,Tehran University of Medical Sciences | Javadian E.,Tehran University of Medical Sciences | And 3 more authors.
Eastern Mediterranean Health Journal | Year: 2012

Shirvan district in north-eastern Islamic Republic of Iran is a new focus of visceral leishmaniasis. This study aimed to identify the vector(s), the parasite and the species composition of sand flies in the district during July- September 2009 using polymerase chain reaction techniques. In all, 2088 sand flies were collected from 3 villages. Nine sand fly species were identified: Phlebotomus kandelakii (Shchurenkova), P. major (Annandale), P. halepensis (Theodor), P. papatasi (Scopoli), P. sergenti (Parrot), P. longidactus (Parrot), P. caucasicus (Marzinovsky), Sergentomyia sintoni (Pringle) and S. sumbarica (Perfil'ev). P. sergenti and P. kandelakii were the most prevalent Phlebotomus species at 31.3% and 10.0% respectively. Of 59 female P. kandelakii, 2 (3.4%) were naturally infected with L. infantum. This is the first finding of natural infection of P. kandelakii by L. infantum in this region suggesting P. kandelakii may be the vector of L. infantum in the area although it is the second most prevalent phlebotomine species. Source


Moghri M.,University of Kashan | Seyed Shahabadi S.I.,University of Bojnourd | Madic M.,University of Nis
Journal of Vinyl and Additive Technology | Year: 2014

Tensile modulus is an important mechanical property of polymer/nanoclay nanocomposites. In this study, response surface method (RSM) and Taguchi-optimized artificial neural network (Taguchi-optimized ANN) were used to model tensile modulus as a function of nanoclay content, melt temperature, screw speed, and feeding rate for (polyamide 6)/nanoclay nanocomposites prepared in a twin-screw extruder. The comparison between Taguchi-optimized-ANN- and RSM-generated plots showed that predictions made by both models were in agreement in general. Coefficient of determination, R2, showed that the RSM model can explain the variation with the accuracy of 0.768, indicating there was no strong correlation. However, from ANOVA, the p value for the RSM model was less than 0.05, signifying that the obtained model could be considered statistically significant. In addition, further assessment in terms of data fitting and prediction capabilities demonstrated the superiority of a properly trained Taguchi-optimized ANN model in characterizing the nonlinear behavior of a response-factors relationship. The Taguchi-optimized ANN model R2 for training data and testing data were 0.965 and 0.902, respectively. Also, the Taguchi-optimized ANN model was developed by using 20% less data in comparison to the RSM model. © 2014 Society of Plastics Engineers. Source


Ameri R.,University of Tehran | Dehghan O.R.,University of Bojnourd
Iranian Journal of Fuzzy Systems | Year: 2011

In this paper we investigate the algebraic properties of dimension of fuzzy hypervector spaces. Also, we prove that two isomorphic fuzzy hypervector spaces have the same dimension. Source


Bahmanyar P.,Ferdowsi University of Mashhad | Mafinezhad Kh.,Ferdowsi University of Mashhad | Bahmanyar M.,University of Bojnourd
IEEE Asia-Pacific Conference on Circuits and Systems, Proceedings, APCCAS | Year: 2010

The high performance of Radio Frequency Micro-Electro-Mechanical Systems (MEMS) based switches like low insertion loss, high isolation and high bandwidth make them to play an important role in microwave switching. This paper presents an RF MEMS shunt capacitive switch for Ka band applications. The effect of various geometric dimensional parameters on the switching behaviour of proposed design using Electro Magnetic 3 Dimension simulator EM3DS software tool is investigated. The switch structure has been optimized on the geometrical sizes. © 2010 IEEE. Source

Discover hidden collaborations