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Intelligent Fractional-Order Controller for SMES Systems in Renewable Energy-Based Microgrid

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1807-1830页

作者： Aadel M.Alatwi Abualkasim Bakeer Sherif A.Zaid Ibrahem E.Atawi Hani albalawi ahmed M.Kassem Electrical Engineering Department Faculty of EngineeringUniversity of TabukTabuk47913Saudi Arabia Industrial Innovation and Robotic Center(IIRC) University of TabukTabuk47731Saudi Arabia Department of Electrical Engineering Faculty of EngineeringAswan UniversityAswan81542Egypt Renewable Energy and Environmental Technology Centre University of TabukTabuk47913Saudi Arabia Electrical Engineering Department Faculty of EngineeringSohag UniversitySohag82524Egypt

An autonomous microgrid that runs on renewable energy sources is presented in this *** has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage ***,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult ***-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and *** suggested dedicated control for the SMES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SMES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum *** suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid *** optimal FOPI+iFOPI controller manages the voltage and frequency of the *** behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed *** simulations were used to evaluate the recommended system’s *** results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and *** addition,the required load demand was accurately ***,the microgrid functioned incredibly well despite SMES and varying wind *** obtained under identical conditions were compared with and without the best FOPI+iFOPI *** utilizing the optimal FOPI+iFOPI controller with SMES,it was found that the microgrid performed better than the microgrid without SMES.

关键词： Fractional-order proportional integral(FOPI) intelligent controller renewable energy resources superconducting magnetic energy storage optimization

Variability in the Content of 25α- and 25β-Steroidal Sapogenins among Thirty Morphologically Different Sudanese Seed Accessions of Fenugreek

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Journal of Life Sciences 2014年第9期8卷 744-757页

作者： Nour ahmed Osman Salah ahmed Elhussein Marzougah Aziz Dager albalawi Department of Chemistry University College at Alwajh University ofTabuk Tabuk 71491 Saudi Arabia Oilseed Chemistry Section National Oilseed Proc. Res. Inst. University of Gezira Wad-Medani Pb 020 Sudan

Seeds of Fenugreek （Trigonellafoenum-graecum L.）, an international spice commodity, are much consumed in Sudan as a food, for flavoring and as a folk-remedy for several ailments, together with local beliefs in nutraceutical benefits. The authors have noted an immense variability in colour and other morphological characters of Fenugreek seeds offered in local Sudanese markets and wondered whether this variability is extended to their chemical composition. Steroidal sapogenins are important chemical constituents of Fenugreek seeds in view of their potential as precursors for the commercial synthesis of steroid drugs and their continually revealed beneficial biological activities. In this study, thirty Sudanese Fenugreek seed accessions collected from different geographical regions in Sudan were analyzed for their 25α-, 25β- and total sapogenin content using a simple and specific infra-red spectroscopic method. The seed accessions exhibited much morphological variability particularly in outer seed coat color and size. Preparative TLC followed by gravimetric analysis showed that steroidal sapogenins, mostly diosgenin and yamogenin, represented more than 70% of the steroids of Fenugreek seeds. Infra-red spectroscopic analysis showed that total 25α-sapogenins （calculated as diosgenin） varied from 0.65% to 1.68%. Total 25β-sapogenin （calculated as yamogenin） varied from 0.38% to 2.03%. The content of total sapogenins （α ＋ β epimeric forms） varied between 1.24% and 3.0% of the oven-dry weight of seeds. β-sapogenins （mostly yamogenin） were dominant over α-sapogenins （diosgenin） in most Sudanese Fenugreek seed accessions.

关键词： Fenugreek seeds Trigonellafoenum-graecum steroidal sapogenins seed morphology variability.

Anticancer and Antifolate Activities of Extracts of Six Saudi Arabian Wild Plants Used in Folk Medicine

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Journal of Life Sciences 2015年第7期9卷 334-340页

作者： Marzough Aziz Dager albalawi Nour ahmed Osman Bashir Amany Tawfik Department of Chemistry University College at Alwajh University of Tabuk Tabuk 71491 Saudi Arabia

Six indigenous folk medicinal plants growing wild in the area of Tabuk, Saudi Arabia which were selected for the study of their phytochemistry as well as their biological activities as antitumor and antifolate agents. Antitumor activities of methanol extracts of the six plants were measured in vitro using three human tumor cell lines （breast, lung and CNS cancers） while antifolate activities were assessed using commercial dihyrofolate reductase obtained from Sigma Co. Among the six plant extracts tested, the most remarkable were those of Caralluma sinaica and Fagonia tenuifolia. Caralluma extract showed strong antitumor activity （low GIso） against the three human tumor cell lines. Fagonia extract, on the other hand, was quite inhibitory to the growth of CNS cancer and breast cancer cell lines but much less so against lung cancer cells. Extracts of both Sonchus oleraceus and Caralluma sinaica were strongly inhibitory to DHFR. These results suggest that the mechanism of anticancer activity of Caralluma plant is through DHFR inhibition but that of Fagonia may follow a different path.

关键词： Saudi Arabia plants Caralluma Fagonia Sonchus anticancer antitumor antifolate antimalarial.

Simultaneous biportal endoscopic management of pineal region tumors in patients with obstructive hydrocephalus:technical notes

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Chinese Neurosurgical Journal 2023年第2期9卷 51-57页

作者： Sultan Al-Saiari Khalid Al Orabi Mohammad Ghazi Abdoh Abdulaziz A.Basurrah Sultan Faez albalawi ahmed A.Farag Neurosurgery Department King Abdullah Medical CityP.O 24246MakkahSaudi Arabia

Background The goal of this study is to show the feasibility and benefits of using the simultaneous biportal endoscopic procedure to treat pineal tumors in patients with obstructive *** We retrospectively reviewed three patients with pineal tumors and acute obstructive hydrocephalus who were treated in one session with a frameless stereotactic guided simultaneous biportal endoscopic third ventriculostomy and endoscopic tumor biopsy performed through two separate ports using one rigid *** In the three patients,ventriculostomy and endoscopic biopsies were *** was no death or morbidity throughout the 45-min *** of the patients’histological findings were *** was diagnosed in two patients who recieved postoperative radiotherapy,and the third patient diagnosed with a *** resonance imaging with flow-sensitive sequences was used to confirm ventriculostomy patency in all patients 6 months after the *** Biportal endoscopic approach enables better visual control of both ***,it allows the surgeon to safely pass the ventriculoscope via the foramen of monro,even if it is ***,during endoscopic tumor biopsy and third ventriculostomy,the intracranial pressure can be smoothly managed using the outlet tubes *** treatment may be an alternative to traditional uniportal endoscopic operations in certain patients.

关键词： Pineal tumors Germinoma Hydrocephalus Endoscopic third ventriculostomy Endoscopic biopsy

The Awareness of Keratoconus among General Population in Saudi Arabia

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Open Journal of Ophthalmology 2021年第1期11卷 49-59页

作者： Rahaf Mohammed Alruwaili Abeer Surihan Alharbi Omar Ali Alghamdi Yahya Abdulrahman Alyahya Nouf Mohammed albalawi Sameer Sohail Alostaz Omar ahmed Asiri Khalid Alarfaj College of Medicine Jouf University Sakaka Saudi Arabia Ophthalmology Department Ohud Hospital Madina Saudi Arabia Ophthalmology Department King Fahad Hospital Albaha Saudi Arabia Ophthalmology Department Burydah Central Hospital Qassim Saudi Arabia College of Medicine Tabuk University Tabuk Saudi Arabia Batterjee Medical College Jeddah Saudi Arabia Faculty of Medicine Taif University Taif Saudi Arabia Ophthalmology Department Imam Abdulrahman Bin Faisal University Dammam Saudi Arabia

Introduction: Keratoconus (KCN) is one of the degenerative corneal disorders, which causes impairment in normal visual acuity with a higher prevalence in Saudi Arabia. The study aimed to assess the awareness and knowledge regarding KCN, its risk factors, and management among the Saudi population. Materials and Methods: A survey was conducted using a pre-tested and validated questionnaire distributed through online platforms. A mixture of convenience and snowball sampling techniques was adopted for sample collection. Our analysis included a final sample size of 837 participant responses. The questionnaire had items related to sociodemographic characteristics (5 items), knowledge (10 items), and source of information (1 item). The mean knowledge scores were calculated and categorized (good, fair, and poor) to assess each participant’s knowledge. Pearson’s chi-square test was used to determine the statistical association between categorical variables. Results: The mean knowledge score was found to be 4.12 ± 2.6, and 67.5% of the participants showed “poor” scores. There was no statistically significant association of knowledge scores observed with any of the sociodemographic details. It was agreed by 76% and 42.5% that genetic predisposition and chronic eye inflammation could predispose to KCN. Only 38.1% (n = 157) agreed that KCN could be treated with optical glasses or contact lenses in the initial stages. Conclusion: The knowledge regarding KCN was not satisfactory among our study population. There is a need to create an increased level of awareness for KCN. Health awareness programs and community campaigns should be organized to raise awareness regarding KCN and better eye health care utilization.

关键词： Ophthalmology Inflammation Keratoconus Blindness

Knowledge and Awareness towards Chronic Kidney Disease Risk Factors in Saudi Arabia

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International Journal of Clinical Medicine 2018年第11期9卷 799-808页

作者： Ibrahim A. Bin ahmed Saleh Hadi Alharbi Fahad A. Alateeq Abdulmalik M. Aloriney Abdullah Abdulhadi Hammad Alharbi Abdul Rahman Ali AlSogair Ali Dawood Mohmmed Almansour Alanoud Mansour Ayed albalawi Hussain Gadelkarim ahmed Faculty of Medicine Al Imam Mohammad ibn Saud Islamic University Riyadh Saudi Arabia College of Medicine University of Hail Hail Saudi Arabia

Background: The risk of CKD is high in Saudi Arabia due to increasingly growing prevalence of its risk factors, such as diabetes, hypertension and obesity. Therefore, the objective of this study was to assess the level of awareness of Saudi population towards CKD risk factors in order to generate platform for future planning. Methodology: This study included 940 apparently healthy Saudi volunteers, their ages ranging from 17 to 65 years old with a mean age of 35 years. A purposeful questionnaire was designed and used for obtaining data about the CKD risk factors. Results: Out of 940 participants, 293 (31.2%) were males and 647 (68.8%) were females, giving males “females” ratio of 1.00:2.21. About 62.3% of the participants were found to believe that DM is one of the main risk factors for CKD, of whom, 74% were males and 57% were females. Approximately 60% of the participants were found believing that hypertension is one of the main risk factors for CKD, of whom 79.5% were males and 51.6% were females. Conclusion: There is an increasing in the prevalence of CKD risk factors among Saudi population. Although, the levels of awareness toward some CKD risk factors are relatively increasing, but more health education efforts are deemed importance.

关键词： CKD Saudi Arabia Hypertension Diabetes Obesity Awareness Risk Factors

Knowledge towards Chronic Kidney Disease Manifestations in Saudi Arabia

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Open Journal of Preventive Medicine 2018年第11期8卷 315-323页

作者： Fahad A. Alateeq Abdulmalik M. Aloriney Saleh Hadi Alharbi Ibrahim A. Bin ahmed Abdullah Abdulhadi Hammad Alharbi Abdul Rahman Ali AlSogair Ali Dawood Mohmmed Almansour Alanoud Mansour Ayed albalawi Hussain Gadelkarim ahmed Faculty of Medicine Al Imam Mohammad Ibn Saud Islamic University Riyadh KSA College of Medicine University of Hail Hail KSA

Background: Increasing awareness level and health education can reduce the burden of Chronic Kidney Disease (CKD) at community base. Therefore, the aim of the present study was to assess the level of knowledge towards CKD manifestations in Saudi Arabia. Methodology: This is a descriptive prospective study including 900 apparently health Saudi volunteers, their ages ranging from 18 to 65 years old with a mean age of 34 years. A purposeful questionnaire was deliberated and used for obtaining data about the CKD. Results: Out of 900 contributors, 268 (29.8%) were males and 632 (70.2%) were females, giving males:females ratio of 1.00:2.36. About 102/900 (11.3%) of the participants (all of them were females) were found to believe that CKD has no specific symptoms. Conclusion: The awareness towards CKD manifestation is relatively low, which necessitates the important of community based intervention including health educational programs.

关键词： CKD Saudi Arabia Awareness Manifestations