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Necessary and Sufficient Optimality Conditions for Relaxed and Strict Control of Forward-Backward Doubly SDEs with Jumps Under Full and Partial Information

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Journal of Systems Science & Complexity 2020年第6期33卷 1804-1846页

作者： al-HUSSEIN abdulrahman GHERBal Boulakhras Department of Mathematics College of ScienceQassim UniversityBuraydah 51452Saudi Arabia Laboratory of Mathematical Analysis Probability and OptimizationUniversity of Mohamed KhiderBiskrua07000Algeria

This paper derives necessary and sufficient conditions of optimality in the form of a stochastic maximum principle for relaxed and strict optimal control problems with *** problems are governed by multi-dimensional forward-backward doubly stochastic differential equations(FBDSDEs)with Poisson jumps and has firstly relaxed controls,which are measure-valued processes,and secondly,as an application,the authors allow them to have strict *** FBDSDEs with jumps are fully-coupled,the forward and backward equations work in different Euclidean spaces in general,the backward equation is Markovian,and the control problems are considered under full information or partial information in terms ofσ-algebras that provide such *** formulation of these equations as well as performance functionals are given in abstract forms to allow the possibility to cover most of the applications available in the ***,coefficients of such equations are allowed to depend on control variables.

关键词： Adjoint equations forward-backward doubly stochastic differential equations maximum principle necessary conditions Poisson process relaxed control strict control sufficient conditions

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5-year follow-up of combined non-topography guided photorefractive keratectomy and corneal collagen cross linking for keratoconus

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International Journal of Ophthalmology(English edition) 2018年第1期11卷 48-52页

作者： abdulrahman Mohammed al-Amri Department of Ophthalmology College of Medicine King Khalid University

AIM： To evaluate the visual outcomes of simultaneous non-topography guided photorefractive keratectomy（PRK） and corneal collagen cross-linking（CXL） in eyes with keratoconus 5 y after the ***： Prospective, interventional, non-randomized, and non-controlled case series design was used. Sixty eyes of 30 patients（16 males and 14 females; age： 21-41 y） with mild, non-progressive（stages 1-2） keratoconus were enrolled. Refraction, uncorrected distance visual acuity（UDVA） and corrected distance visual acuity（CDVA）, flat and steep keratometry readings, and adverse events were evaluated preoperatively and postoperatively. Data were collected preoperatively and postoperatively at 3 mo, 1, 2, 3, 4, and 5 y follow-up visits after combined non-topography-guided PRK with CXL was performed. all patients had at least 5 y of ***： all study parameters showed a statistically significant improvement at 5 y over baseline values. The mean follow-up time was 68.20±4.71 mo（range： 60-106 mo）. Patients showed a significant improvement in UDVA from 1.24±0.79 log MAR prior to combined non-TG-PRK＋CXL to 0.06±0.15 log MAR postoperatively at the time of their last follow-up visit. CDVA significantly increased from 0.06±0.19 log MAR preoperatively to 0.03±0.12 log MAR postoperatively. A significant decrease in the mean spherical equivalent（SE） refraction was observed from-2.28±1.8 to-0.79±0.93 diopters（D）（P〈0.05）, and the manifest sphere decreased from-1.62±1.23 to-0.27±0.21 D（P=0.001）. The manifest cylinder significantly decreased from-1.73±0.86 to-0.29±0.34 D postoperatively（P=0.001）. The mean steep keratometry was 45.13±1.32 vs 47.28±2.12 D preoperatively（P〈0.05）, and the preoperative mean steepest keratometry（Kmax） 48.6±3.1 was reduced significantly to 46.8±2.9 postoperatively（P〈0.05）. CONCLUSION： Combined non-TG-PRK with 15 min CXL is an effective and safe option for correcting mild refractive error and improving visual acuity in patients with mild stable keratoconu

关键词： non-topography guided photorefractive keratectomy corneal collagen cross-linking keratoconus

Stereoselective interactions of chiral dipeptides on amylose based chiral stationary phases

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Science China Chemistry 2015年第3期58卷 519-525页

作者： Imran ali Ashanul Haque Zeid A.al-Othman abdulrahman al-Warthan Leonid Asnin Department of Chemistry Jamia Millia Islamia Central University Department of Chemistry College of Science King Saud University Perm National Research Polytechnic University

Dipeptides are stereo-specifically involved in several biological functions that are challenging to separate enantiomerically. Elution order of enantiomers is an important issue in chiral chromatography. Amylose tris-(3,5-dimethylphenylcarbamate) chiral stationary phase(CSP) is the best and most-widely-used CSP in chiral separations, but experimental data of enantiomeric separation of dipeptides on this CSP is lacking. Simulation studies were conducted to determine the order of elution and the chiral recognition mechanism of didpetides on this CSP. Results indicated that the docking energy of SR-enantiomers were higher than SS-antipodes. The range of docking energies for SR-enantiomers was -7.44 to -5.92 kcal/mol with CSP, but -7.15 to -5.87 kcal/mol for SS-stereoisomers. Therefore it is predicted that SS-enantiomer will elute first, followed by SR-antipode. Furthermore, hydrogen bondings, van der Waal's interactions and electrostatic interactions were observed among SR- and SSenantiomers and chiral grooves of CSP. The number of hydrogen bonds was one in each enantiomer binding except S-ala-R-Tyr, which contained two hydrogen bonds. No hydrogen bond was found in S-ala-R-Trp, S-Leu-S-Trp, and S-Leu-S-Tyr dipeptides bindings. The chiral recognition mechanisms dictate different strengths of stereoselective bindings of the enantiomers on CSP.

关键词： dipeptide enantiomers amylose tris-(3 5-dimethylphenylcarbamate) chiral recognition mechanism elution order Auto Dock 4.2.

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Application of machine learning and deep learning in geothermal resource development: Trends and perspectives

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Deep Underground Science and Engineering 2024年第3期3卷 286-301页

作者： abdulrahman al‐Fakih Abdulazeez Abdulraheem Sanlinn Kaka College of Petroleum Engineering and Geosciences King Fahd University of Petroleum MineralsDhahranSaudi Arabia

This study delves into the latest advancements in machine learning and deep learning applications in geothermal resource development,extending the analysis up to *** focuses on artificial intelligence's transformative role in the geothermal industry,analyzing recent literature from Scopus and Google Scholar to identify emerging trends,challenges,and future *** results reveal a marked increase in artificial intelligence(AI)applications,particularly in reservoir engineering,with significant advancements observed post‐*** study highlights AI's potential in enhancing drilling and exploration,emphasizing the integration of detailed case studies and practical *** also underscores the importance of ongoing research and tailored AI applications,in light of the rapid technological advancements and future trends in the field.

关键词： artificial intelligence deep learning geothermal energy development machine learning

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Gastric antisecretory and antiulcer activity of bovine hemoglobin

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World Journal of Gastroenterology 2013年第21期19卷 3291-3299页

作者： abdulrahman K al Asmari Saud al Omani Ibrahim Elfaki Mohammad Tariq Ahmed al Malki Saeed al Asmary Research Center Prince Sultan Military Medical CityRiyadh 11159Saudi Arabia Department of Surgery Prince Sultan Military Medical CityRiyadh 11159Saudi Arabia Department of Gastroenterology Prince Sultan Military Medical CityRiyadh 11159Saudi Arabia Family and Community Medicine Prince Sultan Military Medical CityRiyadh 11159Saudi Arabia

AIM: To investigate gastric antisecretory and gastro- protective activity of bovine hemoglobin (B-Hb) in rats. METHODS: Adult albino-Wistar rats were divided into groups of 6 animals each. B-Hb in doses of 100, 300 and 900 mg/kg body weight was tested for gastric acid secretion and antiulcer activity. Gastric secretions were measured 6 h after pylorus ligation in rats pretreated with B-Hb. The acidity was measured by titrating gastric contents against 0.01 mol/L NaOH to pH 7. Indomethacin ulcers were produced by oral administration of 30 mg/kg bw in the rats pretreated with B-Hb one hour before indomethacin. Six hours after indomethacin stomach removed and ulcer index was recorded. Ethanol ulcer were produced by 1 mL of ethanol in the rats pretreated with B-Hb 30 min before the *** hour after ethanol stomach were cut open to score ulcers. Histological examination and analysis of gastric wall mucus, non-protein sulfhydryl groups (NP-SH), and myeloperoxidase (MPO) were carried in gastric tissue following ethanol administration. RESULTS: In control rats pylorus ligation for 6 h resulted in the accumulation of 8.1 ± 0.61 mL of gastric secretion. The treatment of the rats with 100, 300 and 900 mg/kg of B-Hb produced a significant decrease in the volume of gastric secretion 5.6 ± 0.63, 5.5 ± 0.75 and 4.7 ± 0.58 mL respectively as compared to the control group [analysis of variance (ANOVA) F = 4.77, P < 0.05]. The lesion area in the control group was found to be 22.4 ± 3.2 mm2 six hours after the administration of indomethacin. Treatment of rats with B-Hb at doses of 100 mg/kg (24.3 ± 3.29 mm2), 300 mg/kg (16.2 ± 1.45 mm2) and 900 mg/kg (12.6 ± 1.85 mm2) produced a dose dependent decreased the lesion scores (ANOVA F = 4.50, P < 0.05). The ulcer index following one hour after 1 mL ethanol was 7.1 ± 0.31. Pretreatment of rats with B-Hb at the doses of 100 mg/kg (2.5 ± 0.42), 300 mg/kg (2.1 ± 0.4) and 900 mg/kg (0.7 ± 0.21) significantly inhibited the formation of gas

关键词： Bovine hemoglobin Gastric ulcers Indomethacin Ethanol Ischemic injury Rats

Opinions and attitudes toward targeted temperature management in the emergency department and intensive care unit in a developing country: a survey study

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World Journal of Emergency Medicine 2023年第2期14卷 138-142页

作者： Abdullah Bakhsh Hadeel alotaibi Sara alothman abdulrahman alothman Rahaf alothman abdulrahman alsulami Malak alamoudi ali alothman ali al-Shareef Department of Emergency Medicine the King Abdulaziz UniversityJeddah 21589Saudi Arabia Faculty of Medicine the King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Anesthesia Intensive Care Unitthe King Abdulaziz UniversityJeddah 21589Saudi Arabia College of Medicine King Saud Bin Abdulaziz University for Health SciencesCollege of MedicineJeddah 21589Saudi Arabia King Abdulaziz Medical City Jeddah 21589Saudi Arabia King Abdullah International Medical Research Center Jeddah 21589Saudi Arabia

INTRODUCTION The past two decades have witnessed one of the most contentious scientific debates in the field of temperature management after cardiac arrest in *** started in 2002,following the publication of two groundbreaking trials showing lower mortality rates and improved neurologic recovery with the use of active cooling.[1,2]International recommendations advocate active cooling in the range of 32–34℃for comatose survivors of out-of-hospital cardiac arrest (OHCA).[3,4]The year2013 marked the tipping point with the release of the TTM 1 trial.

关键词： breaking release showing

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Predictive approach of COVID-19 propagation via multipleterms sigmoidal transition model

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Infectious Disease Modelling 2022年第3期7卷 387-399页

作者： Abdelbasset Bessadok-Jemai abdulrahman A.al-Rabiah Chemical Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia

The COVID-19 pandemic with its new variants has severely affected the whole world socially and *** study presents a novel data analysis approach to predict the spread of *** and logistic models are commonly used to determine the duration at the end of the *** show that these well-known models may provide unrealistic predictions for countries that have pandemics spread with multiple peaks and waves.A new prediction approach based on the sigmoidal transition(ST)model provided better estimates than the traditional *** this study,a multiple-term sigmoidal transition(MTST)model was developed and validated for several countries with multiple peaks and *** approach proved to fit the actual data better and allowed the spread of the pandemic to be accurately *** UK,Italy,Saudi Arabia,and Tunisia,which experienced several peaks of COVID-19,were used as case *** MTST model was validated for these countries for the data of more than 500 *** results show that the correlating model provided good fits with regression coefficients(R2)>*** estimated model parameters were obtained with narrow 95%confidence interval *** has been found that the optimum number of terms to be used in the MTST model corresponds to the highest R^(2),the least RMSE,and the narrowest 95%confidence interval having positive bounds.

关键词： COVID-19 Pandemic SIR Logistic Sigmoidal transition Modeling

Chemical composition of essential oil of Thymus vulgaris collected from Saudi Arabian market

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Asian Pacific Journal of Tropical Biomedicine 2017年第2期7卷 147-150页

作者： abdulrahman Khazim al-Asmari Md Tanwir Athar Ahmed Abdullah al-Faraidy Mohammed Salim almuhaiza Department of Research Center Prince Sultan Military Medical CityRiyadhSaudi Arabia Department of Psychiatry Prince Sultan Military Medical CityRiyadhSaudi Arabia Department of Dentistry Prince Sattam Bin Abdulaziz UniversityAl-KharjSaudi Arabia

Objective: To focus on the analysis of chemical constituents of the Thymus vulgaris L.(locally known as "Zaitra" or "Za'atar"; Family: Lamiaceae) which is available in the market of Saudi ***: The Zaitra oil was analyzed by gas chromatography-mass spectrometry. The mass spectra were compared with the standard spectra available in National Institute Standard and Technique ***: The results indicated that the Thymus oil is composed of many chemical compounds including a pinene, thymol and caryophyllene which are biologically active and also used in various ***: It can be concluded that the Thymus vulgaris due to presence of many bioactive compounds can be used as a new potential source of medicine for the treatment of various types of illness.

关键词： Essential oil GC–MS Saudi Arabian herbs Thymus vulgaris

CBOD Model for Changing the Position of Real Furniture Items Using Mobile AR

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CBOD Model for Changing the Position of Real Furniture Items...

作者： al-YAFEAI ENTESAR abdulrahman HUSSEIN 湖南大学

学位级别：硕士

当前和家具有关的增强现实应用程序提供了将虚拟家具添加到虚拟环境中的能力,但它们无法虚拟移动现有的实体家具。实际很多用户在添置或更换家具时,需要考虑已有的家具和新家具的重新摆放,且很多实体家具难以移动,因此虚拟移动实体家具... 详细信息

当前和家具有关的增强现实应用程序提供了将虚拟家具添加到虚拟环境中的能力,但它们无法虚拟移动现有的实体家具。实际很多用户在添置或更换家具时,需要考虑已有的家具和新家具的重新摆放,且很多实体家具难以移动,因此虚拟移动实体家具的功能非常有用。本文提出了一种检测实体家具并使用改进的显着对象检测(Salient Object Setection,SOD)虚拟移动它们的方法,以区分不同的家具并创建它们的虚拟副本。虚拟副本可以在增强现实应用程序中移动。我们的贡献是结合不同大小的感受域,并采用残余块(Residual U-block)从不同尺度收集上下文信息,然后产生配置得当的残余块(Residual U-block)。它使我们能够在不显着增加计算成本的情况下增加每个结构的深度。这种方法使用了无需使用预定义的函数的深度网络训练。来自DUTS的家具数据集和用于物体检测的卷积块CBOD-Net架构用于提高家具物品检测的准确性。测试表明,CBOD-Net架构使我们的结果更加准确。我们使用Unity平台制作了IOS(ARKit)和Android(ARCore)应用程序。在我们的案例中,我们制作了一个增强现实在线家具购物应用程序,并添加了重新排列用户家具的功能。我们应用CBOD-Net来实现家具的显着目标检测和家具周围背景的替换。实验证明我们的改进方法有助于改善用户购买家具时的体验。

关键词：显著性目标检测增强现实深度学习