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Forecasting Stock Volatility Using Wavelet-based Exponential Generalized Autoregressive Conditional Heteroscedasticity Methods

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Intelligent Automation & Soft Computing 2023年第3期35卷 2589-2601页

作者： Tariq T.Alshammari Mohd Tahir Ismail nawaf n.hamadneh S.Al Wadi Jamil J.Jaber nawa Alshammari Mohammad H.Saleh School of Mathematical Science Universiti Sains MalaysiaPenangMalaysia Department of Risk Management and Insurance Faculty of BusinessThe University of JordanJordan Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadhSaudi Arabia

In this study,we proposed a new model to improve the accuracy of fore-casting the stock market volatility *** hypothesized model was validated empirically using a data set collected from the Saudi Arabia stock Exchange(Tada-wul).The data is the daily closed price index data from August 2011 to December 2019 with 2027 *** proposed forecasting model combines the best maximum overlapping discrete wavelet transform(MODWT)function(Bl14)and exponential generalized autoregressive conditional heteroscedasticity(EGARCH)*** results show the model's ability to analyze stock market data,highlight important events that contain the most volatile data,and improve forecast *** results were compared from a number of mathematical mod-els,which are the non-linear spectral model,autoregressive integrated moving aver-age(ARIMA)model and EGARCH *** performance of the forecasting model will be evaluated based on some of error functions such as Mean absolute percentage error(MAPE),Mean absolute scaled error(MASE)and Root means squared error(RMSE).

关键词： Predictive analytics mathematical models volatility index EGARCH model

Artificial neural networks for Prediction of COVID-19 in Saudi Arabia

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Computers, Materials & Continua 2021年第3期66卷 2787-2796页

作者： nawaf n.hamadneh Waqar A.Khan Waqar Ashraf Samer H.Atawneh Ilyas Khan Bandar n.hamadneh Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia Department of Mechanical Engineering College of EngineeringPrince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia Department of Mathematics and natural Sciences College of Sciences&Human StudiesPrince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia College of Computing and Informatics Saudi Electronic UniversityRiyadh11673Saudi Arabia Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh City72915Vietnam King Abdullah University Hospital University of Science and TechnologyIrbid22110Jordan

In this study,we have proposed an artificial neural network(Ann)model to estimate and forecast the number of confirmed and recovered cases of COVID-19 in the upcoming days until September 17,*** proposed model is based on the existing data(training data)published in the Saudi Arabia Coronavirus disease(COVID-19)situation—*** Prey-Predator algorithm is employed for the *** perceptron neural network(MLPnn)is used in this *** improve the performance of MLPnn,we determined the parameters of MLPnn using the prey-predator algorithm(PPA).The proposed model is called the MLPnn–*** performance of the proposed model has been analyzed by the root mean squared error(RMSE)function,and correlation coefficient(R).Furthermore,we tested the proposed model using other existing data recorded in Saudi Arabia(testing data).It is demonstrated that the MLPnn-PPA model has the highest performance in predicting the number of infected and recovering in Saudi *** results reveal that the number of infected persons will increase in the coming days and become a minimum of *** number of recoveries will be 2000 to 4000 per day.

关键词： COVID-19 Ann modeling multilayer perceptron neural network prey-predator algorithm

Computation Analysis of Brand Experience Dimensions: Indian Online Food Delivery Platforms

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Computers, Materials & Continua 2021年第4期67卷 445-462页

作者： Sufyan Habib nawaf n.hamadneh SAl wadi Ra’ed Masa’deh Department of Business Administration College of Administration and FinanceSaudi Electronic UniversityRiyadh11673Saudi Arabia Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia Department of Risk Management and Insurance The University of JordanAmmanJordan Management Information Systems Department School of BusinessThe University of JordanAmmanJordan

Online Food Delivery Platforms(OFDPs)has witnessed phenomenal growth in the past few years,especially this year due to the COVID-19 *** Pandemic has forced many governments across the world to give momentum to OFD services and make their presence among the *** Presence of several multinational and national companies in this sector has enhanced the competition and companies are trying to adapt various marketing strategies and exploring the brand experience(BEX)dimension that helps in enhancing the brand equity(BE)of *** are critical for building brand loyalty(BL)and making companies *** can experience different kinds of brand experiences through feeling,emotions,affection,behavior,and *** present research work is taken up to analyze the factors affecting BEX and its impact on BL and BE of the OFDPs and analyze the mediating role of BL in the relationship between BEX and BE of the OFDPs in the Indian context.A survey of 457 Indian customers was carried out.A questionnaire was used for data collection and a mediation study was used to test hypothesized *** computational analysis reveals that BEX influences the BL and BE of *** study further indicates that BL mediates the relationship between BEX and BE of *** effective marketing and relationship management practices will help company to enhance BEX that will enable in enhancing BL and raising BE of their *** therefore provides a more thorough analysis of BEX constructs and their consequences than previous *** of the managerial implication,limitations,and scope of future research are also presented in the study.

关键词： Hypothesis tests brand experience online food delivery platform statistical tests COVID-19

Application of Metaheuristic Algorithms for Optimizing Longitudinal Square Porous Fins

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Computers, Materials & Continua 2021年第4期67卷 73-87页

作者： Samer H.Atawneh Waqar A.Khan nawaf n.hamadneh Adeeb M.Alhomoud College of Computing and Informatics Saudi Electronic UniversityRiyadh11673Saudi Arabia Department of Mechanical Engineering College of EngineeringPrince Mohammad bin Fahd UniversityAl Khobar31952Saudi Arabia Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia

The objectives of this study involve the optimization of longitudinal porous fins of square cross-section using metaheuristic algorithms.A generalized nonlinear ordinary differential equation is derived using Darcy and Fourier’s laws in the energy balance around a control volume and is solved numerically using RFK 45 *** temperature of the base surface is higher than the fin surface,and the fin tip is kept adiabatic or cooled by convection heat *** other pertinent parameters include Rayleigh number(100≤Ra≤10^(4)),Darcy number,(10^(−4)≤Da≤10^(−2)),relative thermal conductivity ratio of solid phase to fluid(1000≤kr≤8000),nusselt number(10≤nu≤100),porosity(0.1≤φ≤0.9).The impacts of these parameters on the entropy generation rate are investigated and optimized using metaheuristic *** computer science,metaheuristic algorithms are one of the most widely used techniques for optimization *** this research,three metaheuristic algorithms,including the firefly algorithm(FFA),particle swarm algorithm(PSO),and hybrid algorithm(FFAPSO)are employed to examine the performance of square *** is demonstrated that FFA-PSO takes fewer iterations and less computational time to converge compared to other algorithms.

关键词： Optimization firefly algorithm particle swarm algorithm hybrid algorithms porous media entropy generation rate

Estimating Loss Given Default Based on Beta Regression

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Computers, Materials & Continua 2021年第3期66卷 3329-3344页

作者： Jamil J.Jaber noriszura Ismail Siti norafidah Mohd Ramli Baker Albadareen nawaf n.hamadneh Department of Risk Management and Insurance The University of JordanAqaba77111Jordan Universiti Kebangsaan Malaysia Department of Mathematical SciencesMalaysia Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia

Loss given default(LGD)is a key parameter in credit risk management to calculate the required regulatory minimum *** internal ratings-based(IRB)approach under the Basel II allows institutions to determine the loss given default(LGD)on their *** this study,we have estimated LGD for a credit portfolio data by using beta regression with precision parameter(∅)and mean parameter(μ).The credit portfolio data was obtained from a banking institution in Jordan;for the period of January 2010 untilDecember *** the first stage,we have used the“outstandingamount”and“amount of borrowing”to find LGD of each default borrower(494 out of 4393 borrower).In the second stage,we fit univariate parametric distributions to the LGD data to obtain the beta *** that,we have estimated the values of∅based on microeconomic variables(SPP,OE and LR).Moreover,we have estimated the values ofμbased on macroeconomic variables(GDP and Inflation rate).Finally,we have compared between six different link functions(Logit,loglog,probit,cloglog,cauchit,and log),which have used with∅andμ.The results show that Beta regression with probit link function has the highest R-squared with accepted measurements for logL,AIC and BIC.

关键词： Credit risk loss given default parametric distribution regression model

Minimizing Total Tardiness in a Two-Machine Flowshop Scheduling Problem with Availability Constraints

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Intelligent Automation & Soft Computing 2023年第1期35卷 1119-1134页

作者： Mohamed Ali Rakrouki Abeer Aljohani nawaf Alharbe Abdelaziz Berrais Talel Ladhari Applied College Taibah UniversitySaudi Arabia University of Tunis TunisTunisia

In this paper,we consider the problem of minimizing the total tardiness in a deterministic two-machine permutationflowshop scheduling problem subject to release dates of jobs and known unavailability periods of *** theoretical and practical importance of minimizing tardiness inflowshop scheduling environment has motivated us to investigate and solve this interested two-machine scheduling *** that solve this important optimality criterion inflowshop environment are mainly *** fact,despite the n P-hardnessin the strong sense of the studied problem,to the best of our knowledge there are no approximate algorithms(constructive heuristics or metaheuristics)or an algorithm with worst case behavior bounds proposed to solve this ***,the design of new promising algorithms is *** developfive metaheuristics for the problem under *** metaheuristics are:the Particle Swarm Optimization(PSO),the Differential Evolution(DE),the Genetic Algorithm(GA),the Ant Colony Optimization(ACO)and the Imperialist Competitive Algorithm(ICA).All the proposed metaheuristics are population-based *** metaheuristics have been improved by integrating different local search procedures in order to provide more satisfactory,especially in term of quality *** experiments carried out on a large set of randomly generated instances provide evidence that the Imperialist Competitive Algorithm(ICA)records the best performances.

关键词： Optimization machine scheduling flowshop evolutionary algorithms

Human Action Recognition Based on Semi-Supervised Learning

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Human Action Recognition Based on Semi-Supervised Learning

作者： ALKALF nawaf HAMAD n 华南理工大学

学位级别：硕士

考虑到视频中人的动作速度不同,以及目前视频人的动作识别领域中主流方法不使用未知标签数据信息的现状,本文提出了一种基于半监督学习的多尺度人体行为识别算法框架。首先,本文在视频中提取了长度为L和2L的改进的密集轨道特征,并用hog... 详细信息

考虑到视频中人的动作速度不同,以及目前视频人的动作识别领域中主流方法不使用未知标签数据信息的现状,本文提出了一种基于半监督学习的多尺度人体行为识别算法框架。首先,本文在视频中提取了长度为L和2L的改进的密集轨道特征,并用hog、hof和mbh描述符描述这些轨迹。然后对不同尺度下的视频轨迹进行编码,得到相应的视频表示。在半监督学习下,不同尺度下的视频表示对应于不同的视图。最后,本文利用协同EM算法有效地利用未知标签的视频数据信息,提高模型的适应性和识别效率。本文在KTH和HMDB51两个标准动作数据集进行了大量的实验,验证了算法的有效性。实验结果表明,在HMDB51上,本文方法取得了可以和最新方法相比的方法。而在KTH数据集上本文的方法有一定的优势,取得了较好的识别效果。

关键词：行为识别视频特征提取不同长度半监督学习

Updated bone mineral density status in Saudi patients with inflammatory bowel disease

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World Journal of Gastroenterology 2020年第35期26卷 5343-5353页

作者： Mohammed Ewid nawaf Al Mutiri Khalid Al Omar Amal n Shamsan Awais A Rathore nazmus Saquib Anas Salaas Omar Al Sarraj Yaman nasri Ahmed Attal Abdulrahman Tawfiq Hossam Sherif Internal Medicine Department College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Internal Medicine Department Faculty of MedicineCairo UniversityCairo 11562Egypt Gastroenterology Department King Fahad Specialist HospitalBuraidah 52366Al-QassimSaudi Arabia Epidemiology Department College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Medical students College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Critical Care Medicine Department College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Critical Care Medicine Department Faculty of MedicineCairo UniversityCairo 11562Egypt

BACKGROUnD Little is known about inflammatory bowel disease(IBD)burden and its impact on bone mineral density(BMD)among adult patients in Saudi *** the best of our knowledge,our study is the only study to give an update about this health problem in adult Saudi patients with *** is a great risk factor for reduced BMD due to its associated chronic inflammation,malabsorption,weight loss and medication side ***,screening for reduced BMD among patients with IBD is of utmost importance to curb and control anticipated morbidity and mortality among those *** To assess the relationship between IBD and BMD in a sample of adult Saudi patients with *** ninety adult patients with IBD-62 Crohn’s disease(CD)and 28 ulcerative colitis(UC)-were recruited from King Fahad Specialist Hospital gastroenterology clinics in Buraidah,*** enrolled patients were interviewed for their demographic information and for IBD-and BMD-related clinical *** patients had the necessary laboratory markers and dual-energy x-ray absorptiometry scans to evaluate their BMD *** were divided into two groups(CD and UC)to explore their clinical characteristics and possible risk factors for reduced *** The CD group was significantly more prone to osteopenia and osteoporosis compared to the UC group;44%of the CD patients had normal BMD,19%had osteopenia,and 37%had osteoporosis,while 78%of the UC patients had normal BMD,7%had osteopenia,and 25%had osteoporosis(P valuen the CD group,the lowest t-score showed a statistically significant correlation with body mass index(BMI)(r=0.45,Pnd femur z-score(r=0.85,Pn the UC group,the lowest t-score showed only statistically significant correlation with the lumbar z-score(r=0.82,Pnd femur z-score(r=0.80,Pn the CD group with the best cut-off value at≤23.43(m/kg2);area

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Bone mineral density Osteoporosis Fracture risk

Reproductive disturbances among Saudi adolescent girls and young women with type 1 diabetes mellitus

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World Journal of Diabetes 2017年第11期8卷 475-483页

作者： Rim Braham Asirvatham Alwin Robert Maha Ali Musallam Abdulaziz Alanazi nawaf Bin Swedan Mohamed Abdulaziz Al Dawish Department of Endocrinology and Diabetes Diabetes Treatment CenterPrince Sultan Military Medical CityRiyadh 11159Saudi Arabia

AIM To identify reproductive disturbances among adolescent girls and young women with type 1 diabetes mellitus(T1 DM) in Saudi *** This cross sectional study was conducted among 102 female with T1 DM,(aged 13-29 years) who attended the Diabetes Clinic at Diabetes Treatment Center, Prince Sultan Military Medical City, Saudi Arabia between April 2015 to March 2016. Clinical history, anthropometric characteristics and reproductive disturbance were collected through a *** Of 102 patients included in this analysis, 26.5%(27/102) were reported that they experienced an irregular menses. Of these patients, when compared to whose diabetes was diagnosed before menarche(35.4%, 17/48), patients diagnosed with diabetes after menarche(18.5%, 10/54) showed significantly less irregular menses(difference 16.9%, P = 0.04). Similarly, compared to patients diagnosed with diabetes prior to menarche(mean age 12.9 years; n = 48), patients diagnosed with diabetes after menarche(meanage 12.26 years; n = 54) were found to have 0.64 years delay in the age of menarche(P = 0.04). Among the studied patients, 15.7%(16/102) had polycystic ovary syndrome(PCOS). Of these PCOS patients, 37.5%(6/16) had irregular menses, 6.3%(1/16) had Celiac disease, 37.5%(6/16) had Hashimoto thyroiditis and 18.7%(3/16) had *** More than one fourth of the study population with T1 DM experiencing an irregular menses. Adolescent girls and young women diagnosed with diabetes prior to menarche showed higher menstrual irregularity and a delay in the age of menarche.

关键词： Type 1 diabetes Reproductive disturbances Polycystic ovarian syndrome Premature ovarian failure Menarche Saudi Arabia