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.
Kaffashi E.,Amirkabir University of Technology |
Shoorabi M.T.,Zahedan International University |
Bojnourdi S.H.,University of Bojnourd
Proceedings of the 4th International Conference on Computer and Knowledge Engineering, ICCKE 2014 | Year: 2014
Wireless sensor networks (WSNs) have been widely studied and usefully employed in many applications such as monitoring environment, embedded system and so on. Coverage preservation, unique ID assignment and extension of network lifetime are important features for wireless sensor networks. Grouping sensor nodes into clusters is an effective way to improve the network performance. The ratio of covered area to interested area and the lifetime of the network are two of the most challenging issues in WSNs. This is referred to coverage ratio problem. In this paper we consider a more realistic network scenario of WSNs with fixed and heterogeneous sensors. The sensors are distributed randomly and their sensing radius can be controlled in an interval. The goal function and a simple pruning algorithm are presented. The good performance of the evolutionary strategy-up to 99%- shows that it can be utilized in this nonlinear optimization problem. © 2014 IEEE.
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.
Salehi M.,University of Bojnourd |
Tavakkoli-Moghaddam R.,University of Tehran
International Journal of Industrial and Systems Engineering | Year: 2010
Over the past 25 years, the machine-part cell formation problem (CFP) has been the subject of numerous studies. The CFP consists of constructing a set of machine cells and their corresponding product families with the objective of minimising the inter-cell movement of parts while maximising the machine utilisation. This article presents a grouping genetic algorithm for the CFP that uses the grouping efficacy measure. We solve the CFP without pre-determining the number of cells. We also make some effort to improve the efficiency of our algorithm with respect to initialisation of the population, keeping a crossover operator from cloning. The computational results using the grouping efficacy measure for a set of CFPs from the literature are presented. The proposed algorithm performs well on all the test problems, exceeding or matching the solution quality of the results presented in the previous literature for most problems. © 2010 Inderscience Enterprises Ltd.
Sajadi S.M.,University of Tehran |
Ghasemi S.,Islamic Azad University at Najafabad |
Vahdani H.,University of Bojnourd
International Journal of Industrial and Systems Engineering | Year: 2016
Healthcare issues have a special role in the people's lives in most societies. Hospitals are the most important centres of healthcare delivery services. The emergency department (ED) of a hospital is a critical unit as it is related to the life and death of the patients where time plays vital role in patients' health. Also, nowadays the cost of healthcare services is exponentially rising. These are leading hospital managers to offer patients faster services with better quality with concern to hospital limitations. Nurse scheduling has an important effect on time and quality of services. It is usually written by hand by the supervisor of the department. This thesis is proposing mathematical method for nurse scheduling that fulfil the hospital limitations and nurse preferences while minimising the patients' waiting queue time. In order to reach the aforementioned objective, the emergency department of a governmental hospital is simulated by arena and simulated annealing algorithm is applied to find the appropriate schedule. Results show that the waiting time of achieved schedule from proposed algorithm is 18% less than existing schedule. © 2016 Inderscience Enterprises Ltd.
Malekpour H.,Islamic Azad University at Najafabad |
Sajadi S.M.,University of Tehran |
Vahdani H.,University of Bojnourd
International Journal of Services and Operations Management | Year: 2016
Due to the effect of stochastic factors such as failure of machines on competitive power of manufacturing organisations in the competitive global marketplace, importance of production planning is doubled. In order to deal with the uncertainty conditions in manufacturing systems, failure-prone manufacturing systems have arisen. In this paper, a network of failure-prone manufacturing machines are considered and final product is perishable product. In previous studies, perishable product to network of failure-prone manufacturing machines has not been studied. The purpose of this study is to find the optimum rate of machines production based on hedging point policy such that the average system costs are minimal. Because of uncertainty in such systems, in this paper discrete-event simulation with the help of ARENA software for estimating system costs is used. Taguchi method is employed to determine the optimal values of decision variables. A numerical example will show the efficiency of the proposed approach. © Copyright 2016 Inderscience Enterprises Ltd.
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.
Moghri M.,University of Kashan |
Seyed Shahabadi S.I.,University of Bojnourd |
Madic M.,University of Niš
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.
Ebrahimi A.M.,University of Bojnourd |
Pordanjani T.R.,University of Bojnourd
Iran Occupational Health | Year: 2013
Background and Aim: The aim of the present study was to examine the personality variables of morning-type, rigidity, neuroticism, extroversion, openness, agreeableness and conscientiousness as predictors of shift work tolerance in an industrial company in Ahvaz. Methods: The sample consisted of 245 shift workers which were selected by the use of stratified random sampling. At first the participants divided into two groups (low tolerance shift workers versus high tolerance shift workers) by using Survey of Shift workers. Then each group of participants was evaluated by using NEO questionnaire. In order to analyze the data, the discriminate analysis and in the validation stage, the Pearson's Correlation Coefficient were applied. Results: Findings, confirm the hypothesis of this study. On the other hand, findings revealed that tolerance of shift work can be predicted from Personality variables. Conclusions: The results of this study showed the importance of morning-type, neuroticism, and rigidity as predictors of shift work tolerance. Therefore, in order to select people for shift work systems we recommend to rely on these variables.
PubMed | University of Bojnourd, Ferdowsi University of Mashhad and Mashhad University of Medical Sciences
Type: Journal Article | Journal: Journal of dentistry (Shiraz, Iran) | Year: 2015
During the orthodontic treatment, microbial plaques may accumulate around the brackets and cause caries, especially in high-risk patients. Finding ways to eliminate this microbial plaque seems to be essential.The aim of this study was to compare the antibacterial effects of nano copper oxide (CuO) and nano zinc oxide (ZnO) coated brackets against Streptococcus mutans (S.mutans) in order to decrease the risk of caries around the orthodontic brackets during the treatment.Sixty brackets were coated with nanoparticles of ZnO (n=20), CuO (n=20) and CuO-ZnO (n=20). Twelve uncoated brackets constituted the control group. The brackets were bonded to the crowns of extracted premolars, sterilized and prepared for antimicrobial tests (S.mutans ATCC35668). The samples taken after 0, 2, 4, 6 and 24 hours were cultured on agar plates. Colonies were counted 24 hours after incubation. One-way ANOVA and Tukey tests were used for statistical analysis.In CuO and CuO-ZnO coated brackets, no colony growth was seen after two hours. Between 0-6 hours, the mean colony counts were not significantly different between the ZnO and the control group (p>0.05). During 6-24 hours, the growth of S.mutans was significantly reduced by ZnO nanoparticles in comparison with the control group (p< 0.001). However, these bacteria were not totally eliminated.CuO and ZnO-CuO nanoparticles coated brackets have better antimicrobial effect on S.mutans than ZnO coated brackets.