Model Predictive Control-Based Smart Linear Servo-Motor Driver for a Resonance Frequency Tuner of Azimuth Variable Field Cyclotrons

Mohammad Saleh Sharifi Asadi,Hosein Afarideh,Mitra Ghergherechi,Jong Seo Chai 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.76 No.7

The most important thing in the startup procedure or the long-term operation of radio frequency (RF) cyclotrons especially azimuth variable field (AVF) cyclotrons, is the resonance frequency stability of the cavities. Generally, servo-motors or stepper motors are used to adjust the tuners of cavities. Actually, proportional-integral-derivative (PID) controller-based servo-motor drivers have many problems for long-term operation, such as the tuner's temperature dependence, shot noise, and so on. Our model predictive controller (MPC) or MPC-based smart linear servo-motor driver in a multi-input and single-output state, with artificial intelligence (AI), can solve usual and unusual problems in order to control the speed and/or position. In other words, the MPC is a progressive strategy of process control to control the process and provides satisfaction limitations. Additionally, this real-time controller can reduces the time needed for the startup procedure and minimizes the number of failures during long-term operation.

Artificial neural network-based sodium nitrite NQR analysis in an urban noisy environment

Mohammad Saleh Sharifi A. M.,Hossein Afarideh,Mitra Ghergherehchi,Mehdi Simiari 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.83 No.3

Using the nuclear quadrupole resonance procedure in non-shielded environments requires special measures. For this purpose, noise reduction and interference suppression algorithms have been used to increase signal-to-noise and interference ratio or SNIR. For this aim, two types of antennas are considered, the ferrite core coil antenna as the main antenna receives the free induction decay or FID signal, radio frequency interference or RFI, and noise, and the omnidirectional auxiliary antenna receives the RFI and noise as the algorithm reference noise. To perform the noise and interference cancelation, the weighting factors in auxiliary antenna data are so important, that an artifcial neural network or ANN model has been used to increase the SNIR. In this research, sodium nitrite has been used as a sample, then algorithms have been tested in a nonshielded environment. The resonant frequency of the 200 g sample, by the signal-to-noise ratio improvement of 18.889 dB, the signal-to-interference ratio improvement of 24.819 dB, and the FID signal amplifcation of 16.925 dB, were measured at 4.649 MHz. The main technique in this study was to use an auxiliary antenna to estimate the noise and interference and compute the learned weighting factor before sending the NQR pulse.

Real-time 14N NQR-based sodium nitrite analysis in a noisy field

Sharifi Mohammad Saleh,송호승,Afarideh Hossein,미트라게게르치,Simiari Mehdi 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.12

Noise and Radio-frequency interference or RFI causes a significant restriction on the Free induction Decay or FID signal detection of the Nuclear Quadrupole Resonance procedure. Therefore, using this method in non-isolated environments such as industry and ports requires extraordinary measures. For this purpose, noise reduction algorithms and increasing signal-to-noise-and-interference ratio or SNIR have been used. In this research, sodium nitrite has been used as a sample and algorithms have been tested in a non-isolated environment. The resonant frequencies for the 150 g of test sample were measured at 303 K at about 1 MHz and 3.4 MHz. The main novelty in this study was, (1) using two types of antennas in the receiver to improve adaptive noise and interference cancellation, (2) using a separate helical antenna in the transmitter to eliminate the duplexer, (3) estimating the noise before sending the pulse to calculate the weighting factors and reduce the noise by adaptive noise cancellation, (3) reject the interference by blanking algorithm, (4) pulse integration in the frequency domain to increase the SNR, and (5) increasing the detection speed by new pulse integration technique. By interference rejection and noise cancellation, the SNIR is improved to 9.24 dB at 1 MHz and to 7.28 dB at 3.4 MHz, and by pulse integration 44.8 dB FID signal amplification is achieved, and the FID signals are detected at 1.057 MHz and 3.402 MHz at room temperature

Objective Monitoring of Brace Wearing Time in Adolescents with Scheuermann’s Kyphosis

Pouya Sharifi,Mojtaba Kamyab,Taher Babaee,Mohammad Saleh Ganjavian 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.6

Study Design: This was a prospective cohort study. Purpose: This study aimed to evaluate the potential differences between the objective and subjective bracing compliances of adolescents with Scheuermann’s kyphosis. Overview of Literature: Bracing is a well-documented intervention for managing adolescents with progressive thoracic Scheuermann’s kyphosis, and the brace should be worn 23 hours every day. Most research studies that have investigated the efficacy of bracing have assumed that the patients wore the braces as advised or that the bracing time was measured subjectively. This may be one of the reasons for the conflicting reports regarding the efficacy of bracing. Methods: Nineteen volunteers (11 girls and 7 boys, 12.89±1.77 years) who were prescribed Milwaukee braces for Scheuermann’s kyphosis were enrolled. Each brace was equipped with a miniature temperature logger to record the actual brace wearing time over a period of 3 weeks. The patients and their families were unaware of the mounted sensor. Each participants and/or parent was provided with a questionnaire to record the number of hours for which the brace was worn each day. In addition, the therapist asked each patient and/or his/her parent about the average number of hours that the brace was worn. Results: The compliance rates measured using the temperature logger (16.00±4.90 hours daily) were significantly lower than those reported in the questionnaires (19.52±6.04 hours daily, p<0.001) and the verbal responses (20.21±6.05 hours daily, p<0.001). Moreover, there was no correlation of age, sex, and body mass index with brace compliance. Conclusions: The braces were worn less often than reported by the patients and/or their parents. Therefore, objective compliance assessments of adolescents with Scheuermann’s kyphosis in a brace are recommended for future studies.

Efficacy of plasmapheresis in neutropenic patients suffering from cytokine storm because of severe COVID-19 infection

Alireza Sadeghi,Somayeh Sadeghi,Mohammad Saleh Peikar,Maryam Yazdi,Mehran Sharifi,Safie Ghafel,Farzin Khorvash,Behrooz Ataei,Mohammad Reza Safavi,Elahe Nasri 대한혈액학회 2023 Blood Research Vol.58 No.2

Background With the emergence of the coronavirus disease 2019 (COVID-19) and inability of healthcare systems to control the disease, various therapeutic theories with controversial responses have been proposed. Plasmapheresis was administered as a medication. However, the knowledge of its efficacy and indications is inadequate. This study evaluated the use of plasmapheresis in critically ill patients with cancer. Methods This randomized clinical trial was conducted on 86 patients with malignancies, including a control group (N=41) and an intervention group (N=45) with severe COVID-19 during 2020-21. Both groups were treated with routine medications for COVID-19 management according to national guidelines, and plasmapheresis was applied to the intervention group. C-reactive protein (CRP), D-dimer, ferritin, lactate dehydrogenase, hemoglobin, and white blood cell, polymorphonuclear, lymphocyte, and platelet levels were measured at admission and at the end of plasmapheresis. Other variables included neutrophil recovery, intensive care unit admission, intubation requirements, length of hospital stay, and hospitalization outcomes. Results CRP (P <0.001), D-dimer (P <0.001), ferritin (P =0.039), and hemoglobin (P =0.006) levels were significantly different between the groups after the intervention. Neutrophil recovery was remarkably higher in the case than in the control group (P <0.001). However, plasmapheresis did not affect the length of hospital stay (P=0.076), which could have significantly increased survival rates (P <0.001). Conclusion Based on the study findings, plasmapheresis led to a significant improvement in laboratory markers and survival rate in patients with severe COVID-19. These findings reinforce the value of plasmapheresis in cancer patients as a critical population suffering from neutropenia and insufficient immune responses.