Improvement in Computation of ΔV_10 Flicker Severity Index Using Intelligent Methods

Payman Moallem,Abolfazl Zargari,Arash Kiyoumarsi 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.2

The ΔV_10 or 10-Hz flicker index, as a common method of measurement of voltage flicker severity in power systems, requires a high computational cost and a large amount of memory. In this paper, for measuring the ΔV_10 index, a new method based on the Adaline (adaptive linear neuron) system, the FFT (fast Fourier transform), and the PSO (particle swarm optimization) algorithm is proposed. In this method, for reducing the sampling frequency, calculations are carried out on the envelope of a power system voltage that contains a flicker component. Extracting the envelope of the voltage is implemented by the Adaline system. In addition,in order to increase the accuracy in computing the flicker components, the PSO algorithm is used for reducing the spectral leakage error in the FFT calculations. Therefore, the proposed method has a lower computational cost in FFT computation due to the use of a smaller sampling window. It also requires less memory since it uses the envelope of the power system voltage. Moreover,it shows more accuracy because the PSO algorithm is used in the determination of the flicker frequency and the corresponding amplitude. The sensitivity of the proposed method with respect to the main frequency drift is very low. The proposed algorithm is evaluated by simulations. The validity of the simulations is proven by the implementation of the algorithm with an ARM microcontroller-based digital system. Finally, its function is evaluated with real-time measurements.

Improvement in Computation of ∆ V₁₀ Flicker Severity Index Using Intelligent Methods

Payman Moallem,Abolfazl Zargari,Arash Kiyoumarsi 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.2

The ?V₁? or 10-㎐ flicker index, as a common method of measurement of voltage flicker severity in power systems, requires a high computational cost and a large amount of memory. In this paper, for measuring the ?V₁? index, a new method based on the Adaline (adaptive linear neuron) system, the FFT (fast Fourier transform), and the PSO (particle swarm optimization) algorithm is proposed. In this method, for reducing the sampling frequency, calculations are carried out on the envelope of a power system voltage that contains a flicker component. Extracting the envelope of the voltage is implemented by the Adaline system. In addition, in order to increase the accuracy in computing the flicker components, the PSO algorithm is used for reducing the spectral leakage error in the FFT calculations. Therefore, the proposed method has a lower computational cost in FFT computation due to the use of a smaller sampling window. It also requires less memory since it uses the envelope of the power system voltage. Moreover, it shows more accuracy because the PSO algorithm is used in the determination of the flicker frequency and the corresponding amplitude. The sensitivity of the proposed method with respect to the main frequency drift is very low. The proposed algorithm is evaluated by simulations. The validity of the simulations is proven by the implementation of the algorithm with an ARM microcontroller-based digital system. Finally, its function is evaluated with real-time measurements.

Poster Session : PS 0348 ; Epidemiology and Public Health : Comparison of Health Related Quality of Life Between Two Groups of Veteran and Non-Veteran Spinal Cord Injured Patients

( Payman Salamati ),( Reza Rostami ),( Soheil Saadat ),( Taher Taheri ),( Maryam Tajabadi ),( Ghazale Ranjbari ),( Zohrehsadat Naji ),( Saba Jafarpour ),( Vafa Rahimi Movaghar ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Patients with spinal cord injury (SCI) have a lower health related quality of life (HRQOL) in comparison with both healthy controls and the normal population. The aim of this study was to compare HRQOL between two groups of veteran and non-veteran SCI patients. Methods: Male paraplegic non-veterans who had sustained complete SCI before the year 1988 and were residents of Tehran province, Iran, and a similar group of SCI veterans were enrolled in this study. The participants were interviewed based on the Iranian version of SF-36 questionnaire by two psychologists. Eight sub-scales and two physical and mental component summaries of the instrument were assessed. We used chi-square, odds ratio, Mann-Whitney U, independent t-test, and linear regression for analysis. Results: Overall, 25 veterans and 22 non-veterans were enrolled in the study. The mean age, time since injury, and presence of comorbid illnesses were not signifi cantly different between veterans and non-veterans. A greater number of veterans were married (P=0. 003) and employed (P=0. 047). On average, veterans had more years of formal education than non-veterans (P=0. 001). The mean (SD) bodily pain sub-scale was 72. 73(31. 253) for non-veterans and 49. 7(28. 287) for veterans (P=0. 011). Absence of comorbid illnesses was associated with a better physical component summary (P<0. 001). Employment was associated with a better mental component summary (P=0. 022). Conclusions: We did not fi nd any difference in HRQOL between the two groups except for the bodily pain sub-scale. Further studies with larger sample sizes are recommended.

Improvement in Computation of Δ V₁₀ Flicker Severity Index Using Intelligent Methods

Moallem, Payman,Zargari, Abolfazl,Kiyoumarsi, Arash The Korean Institute of Power Electronics 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.2

The ${\Delta}\;V_{10}$ or 10-Hz flicker index, as a common method of measurement of voltage flicker severity in power systems, requires a high computational cost and a large amount of memory. In this paper, for measuring the ${\Delta}\;V_{10}$ index, a new method based on the Adaline (adaptive linear neuron) system, the FFT (fast Fourier transform), and the PSO (particle swarm optimization) algorithm is proposed. In this method, for reducing the sampling frequency, calculations are carried out on the envelope of a power system voltage that contains a flicker component. Extracting the envelope of the voltage is implemented by the Adaline system. In addition, in order to increase the accuracy in computing the flicker components, the PSO algorithm is used for reducing the spectral leakage error in the FFT calculations. Therefore, the proposed method has a lower computational cost in FFT computation due to the use of a smaller sampling window. It also requires less memory since it uses the envelope of the power system voltage. Moreover, it shows more accuracy because the PSO algorithm is used in the determination of the flicker frequency and the corresponding amplitude. The sensitivity of the proposed method with respect to the main frequency drift is very low. The proposed algorithm is evaluated by simulations. The validity of the simulations is proven by the implementation of the algorithm with an ARM microcontroller-based digital system. Finally, its function is evaluated with real-time measurements.

Effectiveness of intradiscal injection of radiopaque gelified ethanol (DiscoGel^®) versus percutaneous laser disc decompression in patients with chronic radicular low back pain

( Masoud Hashemi ),( Payman Dadkhah ),( Mehrdad Taheri ),( Pegah Katibeh ),( Saman Asadi ) 대한통증학회 2020 The Korean Journal of Pain Vol.33 No.1

Background: Low back pain secondary to discopathy is a common pain disorder. Multiple minimally invasive therapeutic modalities have been proposed; however, to date no study has compared percutaneous laser disc decompression (PLDD) with intradiscal injection of radiopaque gelified ethanol (DiscoGel^®). We are introducing the first study on patient-reported outcomes of DiscoGel^® vs. PLDD for radiculopathy. Methods: Seventy-two patients were randomly selected from either a previous strategy of PLDD or DiscoGel^®, which had been performed in our center during 2016- 2017. Participants were asked about their numeric rating scale (NRS) scores, Oswestry disability index (ODI) scores, and progression to secondary treatment. Results: The mean NRS scores in the total cohort before intervention was 8.0, and was reduced to 4.3 in the DiscoGel^® group and 4.2 in the PLDD group after 12 months, which was statistically significant. The mean ODI score before intervention was 81.25% which was reduced to 41.14% in the DiscoGel^® group and 52.86% in the PLDD group after 12 months, which was statistically significant. Between-group comparison of NRS scores after two follow-ups were not statistically different (P = 0.62) but the ODI score in DiscoGel^® was statistically lower (P = 0.001). Six cases (16.67%) from each group reported undergoing surgery after the follow-up period which was not statistically different. Conclusions: Both techniques were equivalent in pain reduction but DiscoGel^® had a greater effect on decreasing disability after 12 months, although the rate of progression to secondary treatments and/or surgery was almost equal in the two groups.

Impact of a narrative medicine program on reflective capacity and empathy of medical students in Iran

Saeideh Daryazadeh,Payman Adibi,Nikoo Yamani,Roya Mollabashi 한국보건의료인국가시험원 2020 보건의료교육평가 Vol.17 No.-

Purpose: Narrative medicine consists of the expression of medical experiences and the reflection on narratives to foster empathic communication with patients. Reflecting on narratives increases self-awareness and recognition of the feelings of the narrator or the story’smain character, which in turn affects the audience. This study was conducted to examine the impact of a narrative medicine program onthe reflective capacity and empathy of medical students. Methods: A quasi-experimental study was performed during the 2018–2019 academic year at Isfahan University of Medical Sciencesin Iran involving 135 medical interns in 2 groups (control [n=66] and experimental [n=69]). Interns in the experimental group tookpart in seven 2-hour reflective practice sessions, while those in the control group underwent no educational intervention. Pre-test andpost-test assessments were conducted for both groups using 2 valid and reliable tools for the assessment of reflective capacity and empathy. Mean reflection and empathy scores were compared within groups (between pre- and post-test values) and between groups (usingthe paired-t test and the t-test; P≤0.05). Results: The mean reflection and empathy scores of the experimental group significantly increased from pre-test to post-test, but thoseof the control group did not. Moreover, the mean post-test scores were significantly different between the 2 groups (P<0.001). Conclusion: Narrative medicine is an effective teaching method that can improve reflective capacity and empathy, thereby ultimatelypromoting professionalism as a core competency in medicine. Consideration of learning conditions and interdisciplinary teaching arenecessary for implementing a narrative medicine program.

Some properties of tensor centre of groups

Mohammad Reza R. Moghaddam,Payman Niroomand,S. Hadi Jafari 대한수학회 2009 대한수학회지 Vol.46 No.2

Let G⊗G be the tensor square of a group G. The set of all elements a in G such that a⊗g = 1_⊗, for all g in G, is called the tensor centre of G and denoted by Z^⊗(G). In this paper some properties of the tensor centre of G are obtained and the capability of the pair of groups (G,G‘) is determined. Finally, the structure of J_2 (G) will be described, where J_2 (G) is the kernel of the map k : G ⊗ G → G'. Let G⊗G be the tensor square of a group G. The set of all elements a in G such that a⊗g = 1_⊗, for all g in G, is called the tensor centre of G and denoted by Z^⊗(G). In this paper some properties of the tensor centre of G are obtained and the capability of the pair of groups (G,G‘) is determined. Finally, the structure of J_2 (G) will be described, where J_2 (G) is the kernel of the map k : G ⊗ G → G'.

Development of a checklist to validate the framework of a narrative medicine program based on Gagne’s instructional design model in Iran through consensus of a multidisciplinary expert panel

Saeideh Daryazadeh,Nikoo Yamani,Payman Adibi 한국보건의료인국가시험원 2019 보건의료교육평가 Vol.16 No.-

Purpose: Narrative medicine is a patient-centered approach focusing on the development of narrative skills and self-awareness that incorporates “attending, representing, and affiliating” in clinical encounters. Acquiring narrative competency promotes clinical performance, and narratives can be used for teaching professionalism, empathy, multicultural education, and professional development. This study was conducted to develop a checklist to validate the framework of a narrative medicine program through consensus of a panel. Methods: This expert panel study was conducted from 2018 to 2019 at Isfahan University of Medical Sciences, Iran. It included 2 phases: developing a framework in 2 steps and forming an expert panel to validate the framework in 3 rounds. We adapted a 3-stage narrative medicine model with 9 training activities from Gagne’s theory, developed a framework, and then produced a checklist to validate the framework in a multidisciplinary expert panel that consisted of 7 experts. The RAND/UCLA appropriateness method was used to assess the experts’ agreement. The first-round opinions were received by email. Consensus was achieved in the second and third rounds through face-to-face meetings to facilitate interactions and discussion among the experts. Results: Sixteen valid indicators were approved and 100% agreement was obtained among experts (with median values in the range of 7–9 out of a maximum of 9, with no disagreement), and the framework was validated by the expert panel. Conclusion: The 16 checklist indicators can be used to evaluate narrative medicine programs as a simple and practical guide to improve teaching effectiveness and promote life-long learning

SOME PROPERTIES OF TENSOR CENTRE OF GROUPS

Moghaddam, Mohammad Reza R.,Niroomand, Payman,Jafari, S. Hadi Korean Mathematical Society 2009 대한수학회지 Vol.46 No.2

Let $G{\otimes}G$ be the tensor square of a group G. The set of all elements a in G such that $a{\otimes}g\;=\;1_{\otimes}$, for all g in G, is called the tensor centre of G and denoted by $Z^{\otimes}^$(G). In this paper some properties of the tensor centre of G are obtained and the capability of the pair of groups (G, G') is determined. Finally, the structure of $J_2$(G) will be described, where $J_2$(G) is the kernel of the map $\kappa$ : $G{\otimes}\;{\rightarrow}\;G'$.

Methodology of FPGA-Based Mathematical Error-Based Tuning Sliding Mode Controller

Farzin Piltan,Iman Nazari,Sobhan Siamak,Payman Ferdosali 보안공학연구지원센터 2012 International Journal of Control and Automation Vol.5 No.1