• Journal of Power Electronics
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• v.11 no.4
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• pp.499-506
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• 2011

This paper presents an interleaved active-clamping zero-voltage-switching (ZVS) forward-flyback converter without an output choke. The presented topology has two active-clamping circuits with two separated transformers. Because of the interleaved operation of the converter, the output current ripple will be reduced. The proposed converter can approximately share the total load current between the two secondaries. Therefore, the transformer copper loss and the rectifier diodes conduction loss can be decreased. The output capacitor is made of two series capacitors which reduces the peak reverse voltage of the rectifier diodes. The circuit has no output inductor and few semiconductor elements, such that the adopted circuit has a simpler structure, a lower cost and is suitable for high power density applications. A detailed analysis and the design of this new converter are described. A prototype converter has been implemented and experimental results have been recorded with an ac input voltage of 85-135Vrms, an output voltage of 12V and an output current of 16A.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.183-187
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• 2007

A simple and sensitive extractive spectrophotometric method has been described for the determination of buprenorphine either in raw material or in pharmaceutical formulations. The developed method is based on the formation of a colored ion-pair complex (1 : 1 drug/dye) of buprenorphine and bromocresol green (BCG) in buffer pH 3 and extracting in chloroform. The extracted complex shows absorbance maxima at 415 nm. Beer's law is obeyed in the concentration range of 1.32-100.81 μ g mL-1. The proposed method has been applied successfully for the determination of drug in commercial sublingual tablets and injectable dosage form. No significant interference was observed from the excipients commonly used as pharmaceutical aids with the assay procedure.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.195-201
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• 2007

This study investigated the effects of various culture parameters (carbon sources, temperature, initial pH of culture, NaCl concentration, and light) on the growth and canthaxanthin production by Dietzia natronolimnaea HS-1. The results showed that the most effective carbon source for growth and canthaxantin production was glucose, and the best pH and temperature were 7 and $31^{\circ}C$, respectively. In addition, the biomass and canthaxanthin production increased in a medium without NaCl and in the presence of light. Under the optimized conditions, the maximum biomass, total carotenoid, and canthaxanthin production were $6.12{\pm}0.21g/l,\;4.51{\pm}0.20mg/l,\;and\;4.28{\pm}0.15mg/l$, respectively, in an Erlenmeyer flask system, yet increased to 7.25 g/l, 5.48 mg/l, and 5.29 mg/l, respectively, in a batch fermenter system.

• Asian Spine Journal
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• v.12 no.6
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• pp.1146-1153
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• 2018

Many studies have investigated the prevalence of neck pain (NP) and its risk factors in the general population. However, the prevalence of NP among athletes has not yet been systematically investigated. We aimed to systematically review the prevalence of NP in athletes. A comprehensive search was conducted in September 2015 using PubMed, Ovid SP Medline, ISI, and Google Scholar. We included studies in English that reported the prevalence of NP in an athletic population during a defined period of time. We assessed the risk of bias in studies due to various definitions of NP, response rates, and reliability of the study instruments. Two reviewers independently assessed the studies' quality and performed data extraction. Of 1,675 titles identified, eight articles were assessed for risk of bias, and six with low or moderate risk were included. NP was shown to be prevalent in athletes, with a 1-week prevalence ranging from 8% to 45%, a 1-year prevalence ranging from 38% to 73%, and a lifetime prevalence of about 48%. The prevalence of NP in athletes is high. More studies regarding the prevalence and risk factors of NP may be useful for planning educational programs and developing appropriate rehabilitation protocols and preventive guidelines. Researchers are encouraged to perform epidemiologic studies in athletes with a low risk of bias.

• Structural Engineering and Mechanics
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• v.70 no.3
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• pp.339-350
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• 2019

This research focuses on finite element model updating and damage assessment of structures at element level based on global nondestructive test results. For this purpose, an optimization system is generated to minimize the structural dynamic parameters discrepancies between numerical and experimental models. Objective functions are selected based on the square of Euclidean norm error of vibration frequencies and modal assurance criterion of mode shapes. In order to update the finite element model and detect local damages within the structural members, modern optimization techniques is implemented according to the evolutionary algorithms to meet the global optimized solution. Using a simulated numerical example, application of genetic algorithm (GA), particle swarm (PSO) and artificial bee colony (ABC) algorithms are investigated in FE model updating and damage detection problems to consider their accuracy and convergence characteristics. Then, a hybrid multi stage optimization method is presented merging advantages of PSO and ABC methods in finding damage location and extent. The efficiency of the methods have been examined using two simulated numerical examples, a laboratory dynamic test and a high-rise building field ambient vibration test results. The implemented evolutionary updating methods show successful results in accuracy and speed considering the incomplete and noisy experimental measured data.

• Journal of Veterinary Clinics
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• v.40 no.3
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• pp.197-202
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• 2023

Canine lymphoma (cL) is the most common hematopoietic cancer in dogs. Various determinants have been evaluated to find the predisposing factors in both human and canine lymphoma. Due to common risk factors and similar pathways, cL is considered a potential model for non-Hodgkin lymphoma (NHL) in humans. In this case-series study, major hospitals in Tehran consented to take part in this study and between the years of 2020-2022, provided us with 52 cL cases which were approved by the attended pathologist. We designed a questionnaire and collected information about the dogs and their owners. Most of the owners were women, young (younger than 50 years old), had at least diplomas and interestingly were housewives or househusbands. Male dogs with middle to old age (more than 6 years) were mostly referred. The most common characteristics were neutered, normal BCS, purebred, urban but not industrial residence, previous tobacco smoke exposure but no history of previous fungicide or pesticide exposure. Also, most of them did not have any previous autoimmune or immunosuppressive diseases. Presented characteristics should be considered risk determinants but to approve their validity, they should be further evaluated in epidemiological studies.

• Management Science and Financial Engineering
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• v.8 no.1
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• pp.39-51
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• 2002

Special structure of flow networks can reduce the order of the relative existent algorithms. In this paper a special structure of flow network called self-similar f1ow networks is introduced, After describing such networks an efficient algorithm for finding maximum flow is presented. It is shown that this algorithm runs in O(m) time.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.1315-1316
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• 2005

• Membrane and Water Treatment
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• v.7 no.2
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• pp.87-100
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• 2016

A numerical simulation of membrane evaporation process was carried out in this work. The aim of simulation is to describe transport of water through porous membranes applicable to the concentration of aqueous solutions. A three-dimensional mathematical model was developed which considers transport phenomena including mass, heat, and momentum transfer in membrane evaporation process. The equations of model were then solved numerically using finite element method. The results of simulation in terms of evaporation flux were compared with experimental data, and confirmed the accuracy of model. Moreover, profile of pressure, concentration, and heat flux were obtained and analyzed. The results revealed that developed 3D model is capable of predicting performance of membrane evaporators in concentration of aqueous solutions.

• Earthquakes and Structures
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• v.14 no.5
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• pp.449-458
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• 2018

Earthquakes have shown the vulnerability of unreinforced masonry (URM) structures. The aim of this research is to study a technique for in-plane seismic retrofitting of URM walls in which both diagonal and vertical steel strips are added to a single side of a URM wall. Specimens have been tested under quasi-static cyclic lateral load in combination with constant vertical load. The tests show that vertical and diagonal strips cause a significant increase in seismic capacity in terms of both strength (about 200%) and displacement at maximum (about 20%). Furthermore, this technique caused the failure modes of URM walls were influenced.