Novel Average Value Model for Faulty Three-Phase Diode Rectifier Bridges

Rahnama, Mehdi,Vahedi, Abolfazl,Alikhani, Arta Mohammad,Nahid-Mobarakeh, Babak,Takorabet, Noureddine The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

Rectifiers are widely used in industrial applications. Although detailed models of rectifiers are usually used to evaluate their performance, they are complex and time-consuming. Therefore, the Average Value Model (AVM) has been introduced to meet the demand for a simple and accurate model. This type of rectifier modeling can be used to simplify the simulations of large systems. The AVM of diode rectifiers has been an area of interest for many electrical engineers. However, healthy diode rectifiers are only considered for average value modeling. By contrast, faults occur frequently on diodes, which eventually cause the diodes to open-circuit. Therefore, it is essential to model bridge rectifiers under this faulty condition. Indeed, conventional AVMs are not appropriate or accurate for faulty rectifiers. In addition, they are significantly different in modeling. In this paper, a novel application of the parametric average value of a three-phase line-commutated rectifier is proposed in which one diode of the rectifier is considered open-circuited. In order to evaluate the proposed AVM, it is compared with experimental and simulation results for the application of a brushless synchronous generator field. The results clearly demonstrate the accuracy of the proposed model.

Religion as an Alleviating Factor in Iranian Cancer Patients: a Qualitative Study

Rahnama, Mozhgan,Khoshknab, Masoud Fallahi,Maddah, Sadat Seyed Bagher,Ahmadi, Fazlollah,Arbabisarjou, Azizollah Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.18

After diagnosis of cancer, many patients show more inclination towards religion and religious activities. This qualitative study using semi-structured interviews explored the perspectives and experiences of 17 Iranian cancer patients and their families regarding the role of religion in their adaptation to cancer in one of the hospitals in Tehran and a charity institute. The content analysis identified two themes: "religious beliefs" (illness as God's will, being cured by God's will, belief in God's supportiveness, having faith in God as a relieving factor, and hope in divine healing) and "relationship with God during the illness." In general, relationship with God and religious beliefs had a positive effect on the patients adapting to their condition, without negative consequences such as stopping their treatment process and just waiting to be cured by God. Thus a strengthening of such beliefs, as a coping factor, could be recommended through religious counseling.

Modeling of synthesis gas and hydrogen production in a thermally coupling of steam and tri-reforming of methane with membranes

Hamid Rahnama,Mohammad Reza Rahimpour,Mahdi Farniaei,Mohsen Abbasi 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4

In this novel study, tri-reforming process was used as a heat source to proceed steam reforming of methane in a two membrane hydrogen perm-selective Pd/Ag thermally coupled reactor. Results illustrated that H2/CO ratio at the output of steam and tri-reforming sides reached to 6.1 and 0.9, respectively. Additionally the results showed that methane conversion at the output of steam and trireforming sides reached to 31% and 96%, respectively. By increasing the feed flow rate of tri-reforming side from 28,120 to 140,600 kmol h 1, methane conversion and H2 molar flow rate enhanced 40% and 28.64%, respectively.

Novel Average Value Model for Faulty Three-Phase Diode Rectifier Bridges

Mehdi Rahnama,Abolfazl Vahedi,Arta Mohammad Alikhani,Babak Nahid-Mobarakeh,Noureddine Takorabet 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

Rectifiers are widely used in industrial applications. Although detailed models of rectifiers are usually used to evaluate theirperformance, they are complex and time-consuming. Therefore, the Average Value Model (AVM) has been introduced to meetthe demand for a simple and accurate model. This type of rectifier modeling can be used to simplify the simulations of largesystems. The AVM of diode rectifiers has been an area of interest for many electrical engineers. However, healthy dioderectifiers are only considered for average value modeling. By contrast, faults occur frequently on diodes, which eventually causethe diodes to open-circuit. Therefore, it is essential to model bridge rectifiers under this faulty condition. Indeed, conventionalAVMs are not appropriate or accurate for faulty rectifiers. In addition, they are significantly different in modeling. In this paper,a novel application of the parametric average value of a three-phase line-commutated rectifier is proposed in which one diode ofthe rectifier is considered open-circuited. In order to evaluate the proposed AVM, it is compared with experimental andsimulation results for the application of a brushless synchronous generator field. The results clearly demonstrate the accuracy ofthe proposed model.

Immune analysis of cry1Ab-genetically modified potato by in-silico analysis and animal model

Hassan Rahnama,Mahdi Nikmard,Mohsen Abolhasani,Rahim Osfoori,Forough Sanjarian,Ali Akbar Habashi 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.5

The safety of feeding transgenic potato (Solanum tuberosum), resistant to the potato tuber moth, to Wistar rats was examined from an immunological perspective. The genetically modified potato (GMP) was harbouring cry1Ab and nptII genes as target and selectable marker genes, respectively. In-silico analysis reconfirmed that Cry1Ab and NPTII protein sequences have no significant homology to known toxins or known allergens. The Wistar rats were fed a diet containing 20% GMP or its parental control, non-GMP (NGMP), for 90 days. The consumption of GMP food did not affect the growth rate, food intake, food efficiency, and general health status of the rats. There were no significant differences in the serum concentrations of immunoglobulin A (IgA), IgG, IgM, interleukin 6 (IL-6), and IFN-c between GMP and NGMP-fed rats. Based on such data, it is concluded that the transgenic potato had no adverse effect on immunity functions of Wistar rats.

Effectiveness of Teach-Back Self-Management Training Program on Happiness of Breast Cancer Patients

Ahmadidarrehsima, Sudabeh,Rahnama, Mozhgan,Afshari, Mahdi,Bidmeshki, Elahe Asadi Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.10

Self-management training is one of the ways to empower patients to cope with disease. The aim of this before-and-after quasi-experimental study was to determine effects of a teach-back self-management training method on breast cancer patient happiness. Fifty breast cancer patients who visited the Park-e Neshat Limited Surgery Clinic in Kerman, Iran were randomly divided into intervention and control groups after convenience sampling and checking for inclusion eligibility. Data were collected using a demographic questionnaire and the Oxford Happiness Inventory before and after teach-back training and analyzed using SPSS 23. Findings showed no significant difference between mean happiness scores in the two groups before the intervention. However, after the intervention, the mean happiness score in the intervention group increased from 37.2 to 62.9, while it decreased from 41.4 to 29.8 in the control group. These changes were statistically significant (p<0.001). Even after controlling for the effect of confounding factors such as residence location and history of cancer education, the observed differences between the groups were statistically significant (p<0.001). A teach-back self-management training program can increase happiness levels in breast cancer patients. Therefore, the use of this method is recommended to improve self-management and increase happiness.

HOTAIR Long Non-coding RNA: Characterizing the Locus Features by the In Silico Approaches

Hajjari, Mohammadreza,Rahnama, Saghar Korea Genome Organization 2017 Genomics & informatics Vol.15 No.4

HOTAIR is an lncRNA that has been known to have an oncogenic role in different cancers. There is limited knowledge of genetic and epigenetic elements and their interactions for the gene encoding HOTAIR. Therefore, understanding the molecular mechanism and its regulation remains to be challenging. We used different in silico analyses to find genetic and epigenetic elements of HOTAIR gene to gain insight into its regulation. We reported different regulatory elements including canonical promoters, transcription start sites, CpGIs as well as epigenetic marks that are potentially involved in the regulation of HOTAIR gene expression. We identified repeat sequences and single nucleotide polymorphisms that are located within or next to the CpGIs of HOTAIR. Our analyses may help to find potential interactions between genetic and epigenetic elements of HOTAIR gene in the human tissues and show opportunities and limitations for researches on HOTAIR gene in future studies.

HOTAIR Long Non-coding RNA: Characterizing the Locus Features by the In Silico Approaches

Mohammadreza Hajjari,Saghar Rahnama 한국유전체학회 2017 Genomics & informatics Vol.15 No.4

HOTAIR is an lncRNA that has been known to have an oncogenic role in different cancers. There is limited knowledge of genetic and epigenetic elements and their interactions for the gene encoding HOTAIR. Therefore, understanding the molecular mechanism and its regulation remains to be challenging. We used different in silico analyses to find genetic and epigenetic elements of HOTAIR gene to gain insight into its regulation. We reported different regulatory elements including canonical promoters, transcription start sites, CpGIs as well as epigenetic marks that are potentially involved in the regulation of HOTAIR gene expression. We identified repeat sequences and single nucleotide polymorphisms that are located within or next to the CpGIs of HOTAIR. Our analyses may help to find potential interactions between genetic and epigenetic elements of HOTAIR gene in the human tissues and show opportunities and limitations for researches on HOTAIR gene in future studies.

SUPPRESSION OF REGENERATIVE CHATTER IN MACHINE TOOLS THROUGH THE ROBUST STABILITY THEOREM

Simon S. Park,Ramin Rahnama 한국소음진동공학회 2008 한국소음진동공학회 국제학술대회논문집 Vol.2008 No.7

Effects of combined elicitors on parthenolide production and expression of parthenolide synthase (TpPTS) in Tanacetum parthenium hairy root culture

Farzaneh Pourianezhad,Hassan Rahnama,Amir Mousavi,Mahmood Khosrowshahli,Sudabeh Mafakheri 한국식물생명공학회 2019 Plant biotechnology reports Vol.13 No.3

Feverfew (Tanacetum parthenium) is a medicinal herb that has multiple pharmacologic properties. This plant is rich parthenolide (PN). Hairy roots (HRs) culture is a valuable biotechnological tool for the production of plant secondary metabolites. Furthermore, application of elicitors is one of the most effective strategies to induce the metabolite biosynthesis. This study has investigated the effects of various elicitors on the production of PN in feverfew hairy root culture and the expression of parthenolide synthase (TpPTS) gene. Three elicitors were used separately and in combination, including yeast extract (YE) (2.5 mgL− 1), methyl jasmonate (MJ) (100 μM), Ag+ (100 μM), YE + MJ, Ag+ + MJ, YE + Ag+, and YE + MJ + Ag+ which were added to the 1/2MS medium on day 18 and after 48 h and 96 h, hairy roots were collected to determine the PN content. Total RNA was extracted from hairy roots and used for cDNA synthesis and real-time PCR analysis to investigate the gene expression of TpPTS. The PN content was determined by HPLC. The highest PN content (0.05 mg g− 1 dry weight) was achieved after application of elicitors (in 2.5 mgL− 1 YE and 100 μM MJ) and the highest expression of TpPTS gene also occurred after 96 h in the same treatment. It was concluded that some of the combined elicitors could efficiently increase the parthenolide content of feverfew in vitro culture. The additive effect of elicitors might be due to the separate mechanisms of each substance that is acting in an independent pathway.