A maximum power point tracking for a photovoltaic system based on optimum sinusoidal modulated control pulses

Photovoltaic systems have grown rapidly in the last few decades. This growth has enhanced research about this technology, focusing on reducing cost and improving efficiency. Maximum power point tracking (MPPT), which increases the overall efficiency of a PV system, is a main part of a PV system. In this paper, some MPPT methods have been critically reviewed. Fractional open-circuit voltage has been investigated. The approach of a separate PV array to obtain the open circuit voltage (Voc) is adopted. The proposed idea in this paper is based on optimising the control pulses for the DC-DC converter. The generation of control pulses is based on sinusoidal modulated pulse width modulation (SPWM). The output from the DC-DC converter is then fed into a low frequency square wave voltage-fed inverter circuit. The output is a fine sinusoidal waveform, although the inverter operates at a low frequency. The block diagrams and the results are presented

Physicians’ Knowledge of Abdominal Compartment Syndrome and Intra-Abdominal Hypertension in Saudi Arabia: An Online Cross-Sectional Survey Study

Rayan Qutob,1,2 Alanoud Hassan A Alkhannani,1 Turki Yazeed Alassaf,1 Saad Othman Alhokail,1 Ghassan Abdullah Bagazi,1 Abdulmalak Abdullah Alsaleh,1 Mashael kamel alqarni,1 Yousef Alammari,1 Khalid Al Harbi,1 Alyaa Elhazmi,3 Abdullah Ibrahim Bukhari,1 Abdullah Alaryni,1 Abdullah Alghamdi,1 Osamah A Hakami1 1Faculty of Medicine, Imam Mohammad Ibn Saud Islamic University, Riyadh, Saudi Arabia; 2Adult Critical Care Department, Dr. Sulaiman Al-Habib Medical Group, Riyadh, Saudi Arabia; 3College of Medicine, AlFaisal University, Riyadh, Saudi ArabiaCorrespondence: Alanoud Hassan A Alkhannani, Faculty of Medicine, Imam Mohammad Ibn Saud Islamic University, Riyadh, Saudi Arabia, Tel +966 545436837, Email [email protected]: To determine physicians’ knowledge of abdominal compartment syndrome and intra-abdominal hypertension in Saudi Arabia.Methods: A cross-sectional online survey study was conducted on physicians in Saudi Arabia between March and August 2022. A previously developed questionnaire was adapted and used in this study. The survey instrument investigated the knowledge and management of intra-abdominal hypertension and abdominal compartment syndrome among physicians. Logistic regression was used to identify predictors of being knowledgeable about abdominal compartment syndrome and intra-abdominal hypertension.Results: A total of 266 physicians participated in this study. Around one-fifth (21.8%) the study participants were ICU physicians and 25.0% reported that they practice internal medicine. Intra-abdominal hypertension (IAH) and the impact of increased intra-abdominal pressure (IAP) on organ function were terms that the majority of research participants (70.3%) reported they were familiar with. A similar percentage (73.7%) reported that they are familiar with abdominal compartment syndrome (ACS). Around 43.0% of the study participants reported that they do not know how to measure IAP. The most frequently reported (13.5%) intervention in the treatment of IAH and ACS was the use of inotropes or vasopressors. The study participants showed a weak level of knowledge of ACS and IAH with a median score of 3.00 (IQR: 5.00– 2.00), which represents 27.3% of the maximum attainable score. Physicians working at hospitals with 20– 50 ICU beds were 41.0% (odds ratio: 0.59 (CI: 0.37– 0.96)) less likely to be knowledgeable about intra-abdominal hypertension and abdominal compartment syndrome (p≤ 0.05).Conclusion: Physicians demonstrated a low level of IAP and ACS knowledge. To increase the safety of medical practices and enhance clinical outcomes for patients, awareness should be raised about the proper diagnosis and management of IAP and ACS. Future research should focus on developing effective educational strategies to improve physicians’ understanding of IAP and ACS.Keywords: abdominal compartment syndrome, intra-abdominal hypertension, intra-abdominal pressure, knowledge, physicians, Saudi Arabi