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Search Results: 1 - 10 of 8520 matches for " Seyyed Ahmad Hoseini "
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Controller Design for Synchronizing Distributed Generation Systems with the Phase Locked Loop (PLL)
Seyyed Zynolabedin Mousavi,Parviz Amiri,Seyyed Ahmad Hoseini
International Journal of Engineering and Advanced Technology , 2012,
Abstract: In this paper a fuel cell power plant design using phase locked loop method for paralleling a fuel cell with the global network is described. Despite the fact that synchronous systems for scattering generation sources like generators have been used in Iran’s plants, but there has been made fewer efforts in the case of plants based on fuel cell. In this paper an approach is presented for synchronization based on PLL that can reduce the response time to less than 2 seconds and time difference becomes zero in less than 3 seconds. Using the relay auto tuning algorithm in the closed loop system, the frequency fluctuations become less than 0.05% at the output. As in this approach, tuning is based on the DC voltage level, the induction property that makes the PID controller be unstable is reduced and we will have a very stable output wave. This is the main advantage of this controller. Presented control structure is made up of three loops, whichwe will reached frequency to reference frequency by use of first loop and in the next loop we do it’s phasecontrol whit take an integration of frequency, and in the frequencies difference less than 1 Hz. Presented control structure is made up of three loops. Using first loop, the frequency is reached near the reference value and in the next loop the phase is controlled by integration of the frequency, and in the frequency differences less than 1 Hz, the third loops does control frequency in independent way from the phase. Another advantage of this method is that the circuit remains in phase locked state when the phase has been synchronized, and there is no need to consider the time of connection to the network, and finally the output fluctuation is brought into zero. In this paper, it is also built an empirical example of digital synchronizer which is efficient in synchronizing distributed generation systems with the phase locked loop and will be described in detail in continuation.
A New Educational Marketing Mix: The 6ps for Private School Marketing in Iran
Mehrdad Alipour,Ali Aghamohammadi,Reza Ahmadi,Seyyed Hadi Hoseini
Research Journal of Applied Sciences, Engineering and Technology , 2012,
Abstract: This study aims to present a new marketing mix for private schools based on parents' attitudes of non-public school students in Tehran. Each institution needs to survive is to provide marketing services. Educational institutions such as private schools to attract more students who are among the main goals of these institutions need to use Principles of Marketing. The type of hotels or restaurants services varies with educational services. Hence the educational sector particularly private schools need a new marketing model. This study seeks to present a model to be able thereby to increase Students enrollment. Research method of this study was the combination of exploratory, descriptive - survey and analytical. Gathering techniques of data were through both questionnaire and interview. First results obtained from factor analysis, showed that 3 factors obtained from the 6 factors, which are among the traditional marketing mix include: "Price", "promotion" and "product" and three new factors with the "Parent Teacher Communication," professor "and" privilege ". So the effect of each 6 factors on increasing the enrollment students rate were evaluated by test the hypotheses. The current study took nearly one year to be completed (Feb. 2011 to Dec. 2011). This study also was conducted in Tehran city, Iran.
Isolation and Determination of the Most Appropriate Microbial Strain and Fermentation Condition for Single Cell Protein Production from Whey
Seyyed Ahmad Ataie,Shidooshe Dolatshahi
Journal of Research in Health Sciences , 2011,
Abstract: Background: Whey as the sewage of dairy factories with a large amount of BOD (Biochemical oxygen demand 5000 PPM) is a dangerous environmental pollutant. This important Source of lactose (4-5% Lactose) is a useful substrate for producing a large kind of useful products. Method: Single cel1 protein (SCP) is one of these products with a large cost of nutrition and comparable with other proteins. Now it is a nutrient regulator for herbivorous animal and birds. Results: In this research the microbial strain was chosen from a lot of microorganisms in whey. The criterions of election were the weight of dried Biomass, rate of lactose reduction in whey, the rate of microbial growth and the reduction of chemical oxygen demand (COD). Conclusions: The elected microorganism was yeast. The optimum conditions of fermentation were, 31 oc, pH=8.3, agitated at 800 rpm and aeration of 2VVm. After 25 hours fermentation was terminated and centrifugation of broth gave 8.8 g/l Biomass.
The Effect of Authentic Versus Non-authentic Aural Materials on EFL Learners’ Listening Comprehension
Seyyed Ahmad Mousavi,Hasan Iravani
English Language and Literature Studies , 2012, DOI: 10.5539/ells.v2n1p21
Abstract: The question put forward in this study was to pinpoint the impact of the authentic versus non-authentic listening materials on the listening comprehension of Iranian EFL subjects. After random selection, 80 upper-intermediate students from among all language institutes in Khoramshahr and Abadan cities, in Khuzestan province, Iran, took part in this study. The participants participated in two experimental treatment groups. During one semester, they were instructed in listening to authentic radio-tapes and non-authentic listening materials taken from the assorted sources. The results revealed that the participants who were instructed on the basis of authentic radio-tapes had gained a higher degree of listening comprehension and proficiency than non-authentic groups. Given the results of this experiment, the tentative extrapolations could be that some of the assumptions about the futility of teaching authentic listening materials should be rigorously re-examined. That is, the use of aural authentic listening materials in EFL classrooms improves learners’ listening comprehension, and has positive effects on EFL learners.
The Application of Functional Linguistics in Exposing Gender Bias in Iranian High School English Textbooks
Abdullah Gharbavi,Seyyed Ahmad Mousavi
English Language and Literature Studies , 2012, DOI: 10.5539/ells.v2n1p85
Abstract: The purpose of the present study is to find out whether Iranian high school English textbooks are sexist textbooks which discriminate between male and female students based on their sex. Halliday's systemic-functional linguistic theory was used as an innovative framework to language gender bias studies. To this end, four English textbooks currently taught in the Iranian high schools were chosen as a sample of this study. The linguistics analysis revealed that there were more males in the Theme and Rheme position. In other word, males had dominated the communicative positions of the clauses in the textbooks. Also the outcome of the participant role analysis showed that the frequencies of males for different participant’s roles were more than that of females. Thirty males played the role of actors where as only twenty females were in the position of actor throughout the text of these textbooks. Eleven males were found in the role of senser in all clauses of the textbooks. The finding may be attributable to the writer `s attitude, culture, and traditional patriarchal system of Iranian society. Yet another reason why men are more visible than women may be related to the power of the influential policy makers (mostly men) who make curriculum decisions that favor boys and men.
Do Language Proficiency Levels Correspond to Language Learning Strategy Adoption?
Abdullah Gharbavi,Seyyed Ahmad Mousavi
English Language Teaching , 2012, DOI: 10.5539/elt.v5n7p110
Abstract: The primary focus of research on employment of language learning strategies has been on identification of adoption of different learning strategies. However, the relationship between language learning strategies and proficiency levels was ignored in previous research. The present study was undertaken to find out whether there are any relationship between the employment of different strategies and learners' levels of language proficiency. To this end, initially, a simulated TOEFL test (Bailey, R. F., Seetharaman, S., Gavin, C. A., Shukla, N., Penfield, J., and Subramanian, R., 1993) was administered to classify the learners into three classes of proficiency levels: beginning, intermediate, and advanced. Then, Oxford's Strategy Inventory, SILL, (Oxford, 1990b) was used to determine the frequency of the language learning strategies applied by learners. The results indicated that there is a direct relationship between employment of different strategies and proficiency levels. Therefore, the findings, in general, seem convincing enough to enable one to claim that there is a correspondence between the employment of different strategies and proficiency levels. The results of the present study are by no means complete. More research is needed to substantiate the outcome of the current study. One pedagogical implication of the study is that language instructors and syllabus designers should be advised to inform language learners about language learning strategies. Other implications have been discussed.
In(OTf)3asapowerfulandrecyclablecatalystforPechmanncondensationwithoutsolvent
Bahador Karami,Mahtab Kiani,Mohsen Ahmad Hoseini
催化学报 , 2014, DOI: 10.1016/S1872-2067(14)60090-5
Abstract: ?In(OTf)3playstheroleofaLewisacidcatalystinthePechmanncondensationofphenolswithβ-ketoestersundersolvent-freeconditionstogivecoumarinderivatives.Thisnovelandinexpensivemethodhasadvantagessuchasshortreactiontime,excellentproductyields,andavoidstheuseoforganicsolventsinagreementwithgreenchemistryprinciples.Catalystloadingscanbeaslowas1mol%togivehighyieldsofthecorrespondingcoumarinsat80℃.Thecatalystcanberecoveredafterthereaction,andreusedwithonlyaslightdecreaseintheyield.
EVALUATION AND IDENTIFICATION OF WALNUT HEARTWOOD EXTRACTIVES FOR PROTECTION OF POPLAR WOOD
Seyyed Khalil Hosseini Hashemi,Ahmad Jahan Latibari
BioResources , 2011,
Abstract: Walnut (Juglans regia L.) heartwood extractives were identified and their potential for protection of poplar wood was evaluated. Test specimens were prepared from poplar wood (Populus nigra L.) to meet BS 838:1961 requirements. Samples were impregnated with heartwood extractive solution (1.5, 2.5, and 3.5% w/w in ethanol-toluene), followed by 5 hours vacuum desiccator technique to reach complete saturation. Impregnated specimens were exposed to white-rot fungus (Trametes versicolor) for 14 weeks according to BS 838:1961 applying the kolle-flask method. The weight loss of samples was determined after exposure to white-rot fungus. The highest weight loss (36.96%) was observed for untreated control samples and the lowest weight loss (30.40%) was measured in samples treated with 1.5% extractives solution. The analyses of the extracts using GC/MS indicated that major constituents are benzoic acid,3,4,5-tri(hydroxyl) and gallic acid (44.57 %). The two toxic components in the heartwood are juglone (5.15 %) and 2,7-dimethylphenantheren (5.81 %).
TSC2 Deletions and Duplications: A Descriptive Study in Iranian Patients Affected with Tuberous Sclerosis  [PDF]
Hossein Ramandi, Sayyed Mohammad Hossein Ghaderian, Parviz Toosi, Seyyed Hassan Tonekaboni, Ahmad Ebrahimi, Nasim Hatamnejadian
American Journal of Molecular Biology (AJMB) , 2014, DOI: 10.4236/ajmb.2014.43018
Abstract:

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by formation of benign tumors called hamartomas. Although the TSC is diagnosed based on clinical findings but approximately 85% of individuals who meet diagnostic criteria for TSC a mutation can be identified in TSC2 (69%) and TSC1 (31%). A review of mutation type in TSC1 & TSC2 genes reveals that deletion/duplication assay could be a good screening strategy as a first step in TSC molecular diagnosis. All 41 exons and 5’ untranslated region of TSC2 gene in addition to adjacent PKD1 gene were screened for deletion/duplication in 81 patients DNA samples using multiplex ligation dependent probe amplification (MLPA) method. Deletion/duplication was found in 29 (35.8%) patients, including deletions in 26 (32.0%) patients and duplication in 3 (3.8%). Genotype/phenotype analysis, showed five patients with renal function impairment who have large deletions including PKD gene area. Approximately 65% of cases were sporadic, while the remaining have familial positive history. Deletions/duplications of TSC2 gene were seen in 35.8% of patients with TSC. So it could be concluded that MLPA is a useful testing strategy for molecular screening in sporadic forms of TSC patients. MLPA increased the detection of TSC mutations. MLPA is less expensive, quicker and more precise than direct sequencing and southern blot in the characterization of TSC deletions. This technique is recommended as a standard part of TSC clinical molecular diagnosis.

Role of BrIDA scan in evaluating of a liver mass
Ali Reza Tavassoli,Asieh Sadat Fattahi Masoum,Seyyed Mousa Reza Hoseini,Kamran Adhami
Iranian Journal of Nuclear Medicine , 2010,
Abstract: Diagnosis of a liver mass is so important in approaching to the patient. Hemangioma and Focal Nodular Hyperplasia can be managed conservatively. All other tumoral masses must be treated surgically. In addition to RBC scan for Heangioma, BrIDA scan for FNH can be diagnostic. We report a young woman with large liver mass that BrIDA scan showed FNH and we review the lituratures. Case presentation: A 23 year- old girl was referred to our department with epigastric and right upper quadrants pain from months ago. She had many imaging. In ultrasound and CT scan there was 100 x 70 mm mass in the caudate lobe. RBC liver scan was negative for liver hemangioma. Then we decide to use hepatobiliary scintigraphy. The TC-99m-Br-IDA scan showed radiotracer accumulation in the caudate lobe of liver in early and 4 hours image suggests FNH. This agent is taken up by kupffer cells in focal nodular hyperplasia. The patient managed conservatively after 5 month follow-up her mass had not increase in size. In conclusion, BrIDA scan can help in diagnosis of focal nodular hyperplasia from other her masses especially adenoma, so we can manage patient conservatively
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