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A Hybrid Particle Swarm Optimization to Forecast Implied Volatility Risk

Computers, Materials & Continua 2022年第11期73卷 4291-4309页

作者： Kais Tissaoui Sahbi Boubaker waleed saud alghassab Taha Zaghdoudi Jamel Azibi University of Ha’il Applied CollegeHail CitySaudi Arabia University of Tunis El Manar Faculty of Economic Sciences and Management of Tunisthe International Finance GroupTunisTunisia Department of Computer and Network Engineering College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Research Unit on Study of Systems and Renewable Energy National College of Engineering of MonastirUniversity of MonastirMonastirTunisia LAREQUAD&FSEGT University of Tunis El ManarTunisTunisia University of Jendouba Law FacultyManagement and Economic Sciences of JendoubaTunisia

The application of optimization methods to prediction issues is a continually exploring *** line with this,this paper investigates the connectedness between the infected cases of COVID-19 and US fear index from a forecasting *** complex characteristics of implied volatility risk index such as non-linearity structure,time-varying and nonstationarity motivate us to apply a nonlinear polynomial Hammerstein model with known structure and unknown *** use the Hybrid Particle Swarm Optimization(HPSO)tool to identify the model parameters of nonlinear polynomial Hammerstein *** indicate that,following a nonlinear polynomial behaviour cascaded to an autoregressive with exogenous input(ARX)behaviour,the fear index in US financial market is significantly affected by COVID-19-infected cases in the US,COVID-19-infected cases in the world and COVID-19-infected cases in China,*** performance indicators provided by the developed models show that COVID-19-infected cases in the US are particularly powerful in predicting the Cboe volatility index compared to COVID-19-infected cases in the world and China(MAPE(2.1013%);R2(91.78%)and RMSE(0.6363 percentage points)).The proposed approaches have also shown good convergence characteristics and accurate fits of the data.

关键词： Forecasting Cboe’s volatility index COVID-19 pandemic nonlinear polynomial hammerstein model hybrid particle swarm optimization

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Deep Learning Based Efficient Crowd Counting System

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Computers, Materials & Continua 2024年第6期79卷 4001-4020页

作者： waleed Khalid Al-Ghanem Emad Ul Haq Qazi Muhammad Hamza Faheem Syed Shah Amanullah Quadri Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh12372Saudi Arabia Centre of Excellence in Cybercrime and Digital Forensics Naif Arab University for Security SciencesRiyadh14812Saudi Arabia Center of Excellence for Information Assurance(COEIA) King Saud UniversityRiyadh12372Saudi Arabia

Estimation of crowd count is becoming crucial nowadays,as it can help in security surveillance,crowd monitoring,and management for different *** is challenging to determine the approximate crowd size from an image of the crowd’s *** in this research study,we proposed a multi-headed convolutional neural network architecture-based model for crowd counting,where we divided our proposed model into two main components:(i)the convolutional neural network,which extracts the feature across the whole image that is given to it as an input,and(ii)the multi-headed layers,which make it easier to evaluate density maps to estimate the number of people in the input image and determine their number in the *** employed the available public benchmark crowd-counting datasets UCF CC 50 and ShanghaiTech parts A and B for model training and testing to validate the model’s *** analyze the results,we used two metrics Mean Absolute Error(MAE)and Mean Square Error(MSE),and compared the results of the proposed systems with the state-of-art models of crowd *** results show the superiority of the proposed system.

关键词： Crowd counting EfficientNet multi-head attention convolutional neural network transfer learning

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Discoid meniscus:Treatment considerations and updates

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World Journal of Orthopedics 2024年第6期15卷 520-528页

作者： waleed Albishi Amjad Albaroudi Abdulrahman M Alaseem Sarah Aljasser Ibrahim Alshaygy Abdullah Addar Department of Orthopedic Surgery College of MedicineKing Saud UniversityRiyadh 11362Saudi Arabia

A discoid meniscus is a morphological abnormality wherein the meniscus loses its normal‘C’*** most patients are asymptomatic,patients might still present with symptoms such as locking,pain,swelling,or giving *** resonance imaging is usually needed for confirmation of *** on a constellation of factors,including clinical and radiological,different approaches are chosen for the management of discoid *** purpose of this review is to outline the treatment of discoid meniscus,starting from conservative approach,to the different surgical options for this *** PubMed and Google Scholar databases were used for this *** discussing the treatment of discoid meniscus from 2018 to 2023 were *** there were 369 studies retrieved,and after removal of studies using the exclusion criteria,26 studies were included in this *** such as stability,presence of tear,and morphology can help with surgical *** approaches have been used to treat discoid meniscus,where the choice is tailored for each patient ***,factors that may positively impact patient outcomes include male sex,body mass index<18.5,age at symptom onset<25 years,and duration of symptoms<24 *** conventional approach is partial meniscectomy with or without repair;however,recently,there has been an increased emphasis on discoid-preserving techniques such as meniscoplasty,meniscopexy,and meniscal allograft transplantation.

关键词： Discoid meniscus Saucerization Partial meniscectomy Meniscoplasty Meniscopexy Meniscal allograft transplantation Arthroscopy Knee

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Diagnostic accuracy of ePOS score in predicting DNR labeling after ICU admission:A prospective observational study(ePOS-DNR)

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Journal of Intensive Medicine 2024年第2期4卷 216-221页

作者： Omar E.Ramadan Ahmed F.Mady Mohammed A.Al-Odat Ahmed N.Balshi Ahmed W.Aletreby Taisy J.Stephen Sheena R.Diolaso Jennifer Q.Gano waleed Th.Aletreby Department of Critical Care King Saud Medical CityRiyadhSaudi Arabia Anesthesia Department Faculty of MedicineAin Shams UniversityCairoEgypt Anesthesia Department Faculty of MedicineTanta UniversityTantaEgypt Faculty of Medicine Alexandria UniversityAlexandriaEgypt Nursing Department King Saud Medical CityRiyadhSaudi Arabia

Background Resuscitation can sometimes be futile and making a do-not-resuscitate(DNR)decision is in the best interest of the *** electronic poor outcome screening(ePOS)score was developed to predict 6-month poor outcomes of critically ill *** explored the diagnostic accuracy of the ePOS score in predicting DNR decisions in the intensive care unit(ICU).Methods This study was conducted at the ICU of a tertiary referral hospital in saudi Arabia between March and May ***,we calculated ePOS scores for all eligible consecutive admissions after 48 h in the ICU and recorded the DNR *** ability of the score to predict DNR was explored using logistic ***'s ideal cut-off value was calculated using the DeLong method,and different diagnostic accuracy measures were generated with corresponding 95%confidence intervals(CIs).Results We enrolled 857 patients,125 received a DNR order and 732 did *** average ePOS score of DNR and non-DNR patients was 28.2±10.7 and 15.2±9.7,*** score,as a predictor of DNR order,had an area under receiver operator characteristic(AUROC)curve of 81.8%(95%CI:79.0 to 84.3,P17 was associated with a sensitivity of 87.2(95%CI:80.0 to 92.5,P17 may help guide clinical decisions to withhold or commence resuscitative measures.

关键词： Do-not-resuscitate(DNR) Resuscitation Intensive care unit(ICU) Diagnostic accuracy Sensitivity Specificity

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Computer Forensics Framework for Efficient and Lawful Privacy-Preserved Investigation

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Computer Systems Science & Engineering 2023年第5期45卷 2071-2092页

作者： waleed Halboob Jalal Almuhtadi Center of Excellence in Information Assurance King Saud UniversityRiyadh11653Saudi Arabia College of Computer and Information Sciences King Saud UniversityRiyadh11451Saudi Arabia

Privacy preservation(PP)in Digital forensics(DF)is a conflicted and non-trivial *** solutions use the searchable encryption concept and,as a result,are not efficient and support only a keyword ***,the collected forensic data cannot be analyzed using existing well-known digital *** research paper first investigates the lawful requirements for PP in DF based on the organization for economic co-operation and development OECB)privacy *** have an efficient investigation process and meet the increased volume of data,the presented framework is designed based on the selective imaging concept and advanced encryption standard(AES).The proposed framework has two main modules,namely Selective Imaging Module(SIM)and Selective Analysis Module(SAM).The SIM and SAM modules are implemented based on advanced forensic format 4(AFF4)and SleuthKit open source forensics frameworks,respectively,and,accordingly,the proposed framework is evaluated in a forensically sound *** evaluation result is compared with other relevant works and,as a result,the proposed solution provides a privacy-preserving,efficient forensic imaging and analysis process while having also sufficient ***,the AFF4 forensic image,produced by the SIM module,can be analyzed not only by SAM,but also by other well-known analysis tools available on the market.

关键词： Digital forensics digital evidence AFF4 privacy preservation selective imaging

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Big Data Analytics:Deep Content-Based Prediction with Sampling Perspective

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Computer Systems Science & Engineering 2023年第4期45卷 531-544页

作者： waleed Albattah Saleh Albahli Department of Information Technology College of ComputerQassim UniversityBuraydahSaudi Arabia

The world of information technology is more than ever being flooded with huge amounts of data,nearly 2.5 quintillion bytes every *** large stream of data is called big data,and the amount is increasing each *** research uses a technique called sampling,which selects a representative subset of the data points,manipulates and analyzes this subset to identify patterns and trends in the larger dataset being examined,and finally,creates *** uses a small proportion of the original data for analysis and model training,so that it is relatively faster while maintaining data integrity and achieving accurate *** deep neural networks,AlexNet and DenseNet,were used in this research to test two sampling techniques,namely sampling with replacement and reservoir *** dataset used for this research was divided into three classes:acceptable,flagged as easy,and flagged as *** base models were trained with the whole dataset,whereas the other models were trained on 50%of the original *** were four combinations of model and sampling *** F-measure for the AlexNet model was 0.807 while that for the DenseNet model was *** 1 was the AlexNet model and sampling with replacement,achieving an average F-measure of *** 3 was the AlexNet model and reservoir *** had an average F-measure of *** 2 was the DenseNet model and sampling with replacement,achieving an average F-measure of ***,combination 4 was the DenseNet model and reservoir *** had an average F-measure of ***,we conclude that both models trained on a sampled dataset gave equal or better results compared to the base models,which used the whole dataset.

关键词： Sampling big data deep learning AlexNet DenseNet

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Adaptive Fuzzy Logic Controller for Harmonics Mitigation Using Particle Swarm Optimization

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Computers, Materials & Continua 2022年第6期71卷 4275-4293页

作者： waleed Rafique Ayesha Khan Ahmad Almogren Jehangir Arshad Adnan Yousaf Mujtaba Hussain Jaffery Ateeq Ur Rehman Muhammad Shafiq Department of Electrical&Computer Engineering COMSATS University Islamabad Lahore CampusLahore54000Pakistan Syed Babar Ali School of Science and Engineering Lahore University of Management SciencesLahore54000Pakistan Department of Computer Science College of Computer and Information SciencesKing Saud UniversityRiyadh11633Saudi Arabia Department of Electrical Engineering Superior UniversityLahore54000Pakistan Department of Electrical Engineering Government College UniversityLahore54000Pakistan Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea

An excessive use of non-linear devices in industry results in current harmonics that degrades the power quality with an unfavorable effect on power system *** this research,a novel control techniquebased Hybrid-Active Power-Filter(HAPF)is implemented for reactive power compensation and harmonic current component for balanced load by improving the Power-Factor(PF)and Total–Hormonic Distortion(THD)and the performance of a *** work proposed a soft-computing technique based on Particle Swarm-Optimization(PSO)and Adaptive Fuzzy technique to avoid the phase delays caused by conventional control ***,the control algorithms are implemented for an instantaneous reactive and active current(Id-Iq)and power theory(Pq0)in *** prevent the degradation effect of disturbances on the system’s performance,PS0-PI is applied in the inner loop which generate a required dc ***,a comparative analysis of both techniques has been presented to evaluate and validate the performance under balanced load *** presented result concludes that the Adaptive Fuzzy PI controller performs better due to the non-linearity and robustness of the ***,the gains taken from a tuning of the PSO based PI controller optimized with Fuzzy Logic Controller(FLC)are optimal that will detect reactive power and harmonics much faster and *** proposed hybrid technique minimizes distortion by selecting appropriate switching pulses for VSI(Voltage Source Inverter),and thus the simulation has been taken in SIMULINK/*** proposed technique gives better tracking performance and robustness for reactive power compensation and harmonics *** a result of the comparison,it can be concluded that the PSO-basedAdaptive Fuzzy PI system produces accurate results with the lower THD and a power factor closer to unity than other techniques.

关键词： Harmonics compensation soft computing technique hybrid fuzzy PSO based PI controller HSAPF power quality

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Hamstring autograft utilization in reconstructing anterior cruciate ligament:Review of harvesting techniques,graft preparation,and different fixation methods

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World Journal of Orthopedics 2022年第10期13卷 876-890页

作者： waleed Albishi Baraa Baltow Nora Albusayes Ameer A Sayed Hamza M Alrabai Department of Orthopedic Surgery College of MedicineKing Saud UniversityRiyadh 11362Saudi Arabia Department of Orthopedic Surgery AlHada Armed Forces HospitalMinistry of DefenseAlHada 26792Saudi Arabia Department of Orthopedic Surgery King Fahad Armed Forces HospitalMinistry of DefenseJeddah 23311Saudi Arabia

Rupture of the anterior cruciate ligament(ACL)is a common orthopedic *** graft options are available for the reconstruction of ruptured *** the hamstring muscle as an autograft was first described in 1934,and it remains a commonly harvested graft for ACL *** autografts can be harvested using the traditional anteromedial approach or the newer posteromedial *** isolated semitendinosus tendon can be used or combined with the gracilis *** are numerous methods for graft fixation,such as intra-tunnel or extra-tunnel *** comprehensive review discusses the different hamstring muscle harvesting techniques and graft preparation options and fixation *** provides a comprehensive overview for choosing the optimal surgical technique when treating patients.

关键词： Anterior cruciate ligament Anterior cruciate ligament reconstruction Graft fixation Hamstring autograft Infrapatellar nerve injury Patient reported outcomes

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Severe autoimmune hepatitis triggered by varicella zoster infection

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World Journal of Gastroenterology 2009年第8期15卷 1004-1006页

作者： waleed K Al-Hamoudi Gastroenterology and Hepatology Unit (59) Department of Medicine King Saud University PO Box 2925 Riyadh 11461 Saudi Arabia

Autoimmune hepatitis (AIH) is a chronic disease of unknown etiology that is characterized by the presence of circulatory autoantibodies and inflammatory histological changes in the liver. Although the pathogenesis of AIH is not known, it is thought that, in a genetically predisposed individual, environmental factors such as viruses can trigger the autoimmune process. Herpes simplex virus, Epstein-Barr virus, measles virus, and hepatitis viruses are thought to play a role in the etiology of AIH. Proteins belonging to these viruses may be similar to the amino acid chains of different autoantigens in the liver, this causes immune cross reactions and liver tissue damage. We report a case of severe AIH following varicella zoster infection in a 23-year-old man, and speculate that, based on the molecular mimicry hypothesis, the liver damage was caused by an immune cross reaction to the viral proteins. Varicella-zoster-induced AIH has not been reported previously.

关键词：自身免疫性肝炎带状疱疹感染夫精人工授精单纯疱疹病毒免疫交叉反应水痘带状疱疹重症病因不明

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Diabetes mellitus is not associated with worse short term outcome in patients older than 65 years old post-liver transplantation

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World Journal of Hepatology 2023年第2期15卷 274-281页

作者： Saad Alghamdi Shaden Alamro Dhari Alobaid Elwy Soliman Ali Albenmousa Khalid Ibrahim Bzeizi Saleh Alabbad Saleh A Alqahtani Dieter Broering waleed Al-Hamoudi Liver and Small Bowel Health Centre Department KFSHRCRiyadh 11211Saudi Arabia Department of Medicine KFSHRCRiyadh 11211Saudi Arabia Department of Internal Medicine Minia UniversityMinya 61519Egypt Division of Gastroenterology and Hepatology Johns Hopkins UniversityBaltimoreMD 21287United States Liver Disease Research Center Department of MedicineCollege of MedicineKing Saud UniversityRiyadh 11451Saudi Arabia

BACKGROUND Non-alcoholic fatty liver disease is a global health care challenge and a leading indication of liver transplantation(LT).Hence,more patients with diabetes mellitus(DM)are undergoing LT,especially,above the age of *** To evaluate the impact of DM on short-term outcomes post-LT in patients over the age of *** We collected data of patients who underwent LT from January 2001 until December 2019 using our electronic medical *** assessed the impact of DM on short-term outcomes,one-year,post-LT based on the following variables:Survival at one year;acute cellular rejection(ACR)rates;intensive care unit(ICU)and hospital length of stay;and *** Total of 148 patients who are 65 year or older underwent LT during the study *** mean age is 68.5±3.3 years and 67.6%were *** median Model for End-stage Liver Disease score at time of transplantation was 22(6-39),39%of patients had hepatocellular carcinoma and 77.7%underwent living donor *** one-year survival was similar between DM patients and others,91%.ACR occurred in 13.5%of patients(P=0.902).The median ICU stay is 4.5-day P=*** rates of ICU and 90-d readmission were similar(P=0.821)and(P=0.194),*** The short-term outcome of elderly diabetic patients undergoing LT is similar to *** presence of DM in elderly LT candidates should not discourage physicians from transplant consideration in this cohort of patients.

关键词： Acute cellular rejection Diabetes mellitus Elderly Graft survival Liver transplantation

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