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Fractional synergetic tracking control for robot manipulator

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Journal of Control and Decision 2024年第1期11卷 139-152页

作者： Asma saif Raouf Fareh saif Sinan Maamar Bettayeb Department of Electrical Engineering University of SharjahSharjahUAE Department of Electrical Engineering École de technologie supérieureMontrealCanada CEIES King Abdulaziz UniversityJeddahSaudi Arabia

This work takes advantage of synergetic control theory and fractional calculus to develop and propose fractional synergetic control(FSC)strategy for Four Degrees of Freedom(4-DOF)robot *** proposed fractional synergetic control is designed to track a joint space as well as workspace desired *** calculus gives more flexibility in the design since it has a wider stability *** to that,as stated in the literature,compared to a similar approach such as sliding mode control,the synergetic control approach converges faster to the equilibrium point,without chattering with a fast *** paper proposes a new control strategy that takes advantage of fractional calculus and synergetic control *** proposed control strategy is tested experimentally on a 4-DOF manipulator to study the performance of the proposed control *** stability of the closed-loop system is proved using the Lyapunov *** experimental results have shown that the proposed FSC design has achieved a good tracking performance.

关键词： Synergetic control robust control robot manipulator fractional controller

Hydroelectric and Hydrogen Storage Systems for Electric Energy Produced from Renewable Energy Sources

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Energy Engineering 2024年第10期121卷 2719-2741页

作者： saif Serag Adil Echchelh Biagio Morrone Department of Engineering Universitàdella Campania“Luigi Vanvitelli”Aversa(CE)81031Italy Laboratory of Electronics Treatment Information Mechanic and EnergeticUniversity of Ibn TofailKenitra14000Morocco

Renewable energy sources are essential formitigating the greenhouse effect and supplying energy to resource-scarce ***,their intermittent nature necessitates efficient storage solutions to enhance system efficiency and manage energy *** paper investigates renewable and clean storage systems,specifically examining the storage of electricity generated from renewable sources using hydropower plants and hydrogen,both of which are highly efficient and promising for future energy production and *** study utilizes extensive literature data to analyze the impact of various parameters on the cost per kWh of electricity production in hybrid renewable systems incorporating hydropower and hydrogen storage *** indicate that these hybrid systems can store electricity efficiently and cost-effectively,with production costs ranging from 0.126 to 0.3$/kWh for renewablehydropower systems and 0.118 to 0.42$/kWh for renewable-hydrogen systems,with expected cost reductions over the next decade due to technological advancements and increased market *** novelty of this study lies in its comprehensive comparison of hybrid renewable systems integrating hydropower and hydrogen storage,providing detailed cost analysis and future *** identifies key parameters influencing the cost and efficiency of these systems,offering insights into optimizing storage solutions for renewable ***,this research underscores the potential of hybrid systems to reduce dependency on fossil fuels,particularly during peak demand periods,and emphasizes the importance of seasonal and geographic considerations in selecting energy *** study highlights the importance of policy support and investment in hybrid renewable systems and calls for further research into optimizing these systems for different seasonal and geographic ***,the integration of renewable energy sources with hydropower and hydrogen storage offers a promising pathwa

关键词： Energy storage hydropower hydrogen renewable energy hybrid system

Linkages among leaf nutrient concentration,resorption efficiency, litter decomposition and their stoichiometry to canopy nitrogen addition and understory removal in subtropical plantation

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Ecological Processes 2024年第02期13卷 90-102页

作者： Jawad Ali Shah Wenfei Liu saif Ullah Honglang Duan Fangfang Shen Yingchun Liao Guomin Huang Jianping Wu Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Institute of Biodiversity School of Ecology and Environmental Science Yunnan University Laboratory of Soil Ecology and Health in Universities of Yunnan Province Yunnan University Jiangxi Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology Nanchang Institute of Technology Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province Institute for Forest Resources and Environment of Guizhou College of ForestryGuizhou University

Background The prevalence of understory removal and anthropogenic nitrogen(N) deposition has significantly altered the ecological processes of forest ecosystems at both regional and global scales. However, it remains a pressing challenge to understand how N deposition and understory removal affect leaf nutrient dynamics, nutrient resorption, litter decomposition, and their linkages for better managing forest ecosystems under nutrient imbalances induced by N enrichment. To address this research gap, a field manipulation experiment was carried out in a subtropical Cunninghamia lanceolata plantation with four treatments including: control(CK), canopy N addition(CN), understory removal(UR), and canopy N addition plus understory removal(CN × UR). Green and senesced leaf N and phosphorus(P) concentrations, N and P resorption efficiencies, litter decomposition, and their correlations were *** The results revealed that the average N concentrations of green early and late leaves in UR were increased by 6.61 and 18.89% compared to CK. UR had the highest whereas CN had the lowest P concentrations in green leaves across the two sampling seasons. Following this, UR, leaf type, season, and their interactions significantly affected leaf N, P, and N:P(P < 0.05). The highest leaf N resorption(32.68%) and P resorption efficiencies(63.96%) were recorded in UR. Litter decomposition was significantly retarded in UR(P < 0.01) relative to CN. The regression analysis demonstrated that leaf nutrient status was significantly interconnected with leaf nutrient resorption efficiencies. In addition, leaf nutrient dynamics were strongly correlated with litter nutrients, indicating that both were *** These findings can deepen our knowledge of biogeochemical cycling and reveal contrasting nutrientacquisition strategies on N and P limitation in response to UR and CN. Considering the P limitation, it is important to note that P was resorbed more efficiently, illustrating a

关键词： Nutrient resorption Nitrogen deposition Litter decomposition Stoichiometry Understory removal Subtropical plantation

Beyond bacteria:Role of non-bacterial gut microbiota species in inflammatory bowel disease and colorectal cancer progression

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World Journal of Gastroenterology 2024年第36期30卷 4078-4082页

作者： Hania Haque Syeda Warisha Zehra Mohammad Shahzaib saif Abbas Nazish Jaffar of Medicine Jinnah Sindh Medical UniversityKarachi 75510SindhPakistan Department of Pathology Jinnah Sindh Medical UniversityKarachi 75510SindhPakistan

This letter emphasizes the need to expand discussions on gut microbiome’s role in inflammatory bowel disease(IBD)and colorectal cancer(CRC)by including the often-overlooked non-bacterial components of the human gut *** highlights how viral,fungal and archaeal inhabitants of the gut respond towards gut dysbiosis and contribute to disease *** such as bacteriophages target certain bacterial species and modulate the immune *** viruses found associated include Epstein-Barr virus,human papillomavirus,John Cunningham virus,cytomegalovirus,and human herpes simplex virus type *** such as Candida albicans and Malassezia contribute by forming tissue-invasive filaments and producing inflammatory cytokines,***,mainly methanogens are also found altering the microbial fermentation *** correspondence,thus underscores the significance of considering the pathological and physiological mechanisms of the entire spectrum of the gut microbiota to develop effective therapeutic interventions for both IBD and CRC.

关键词： Gut microbiota Colorectal cancer Inflammatory bowel disease Dysbiosis Bacteriophages Methanogens Fungi

Luminescence regulation of Sb^(3+)in 0D hybrid metal halides by hydrogen bond network for optical anti-counterfeiting

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Opto-Electronic Advances 2024年第3期7卷 15-25页

作者： Dehai Liang saif M.H.Qaid Xin Yang Shuangyi Zhao Binbin Luo Wensi Cai Qingkai Qian Zhigang Zang Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) Chongqing UniversityChongqing 400044China Department of Physics&Astronomy College of SciencesKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Department of Chemistry and Chemical Engineering Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China Department of Oil Army Logistics Academy of PLAChongqing 401311China

The Sb^(3+) doping strategy has been proven to be an effective way to regulate the band gap and improve the photophysical properties of organic-inorganic hybrid metal halides(OIHMHs).However,the emission of Sb^(3+) ions in OIHMHs is primarily confined to the low energy region,resulting in yellow or red *** date,there are few reports about green emission of Sb^(3+)-doped ***,we present a novel approach for regulating the luminescence of Sb^(3+) ions in 0D C_(10)H_(2)_(2)N_(6)InCl_(7)·H_(2)O via hydrogen bond network,in which water molecules act as agents for hydrogen ***^(3+)-doped C_(10)H_(2)2N_(6)InCl_(7)·H_(2)O shows a broadband green emission peaking at 540 nm and a high photoluminescence quantum yield(PLQY)of 80%.It is found that the intense green emission stems from the radiative recombination of the self-trapped excitons(STEs).Upon removal of water molecules with heat,C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7) generates yellow emis-sion,attributed to the breaking of the hydrogen bond network and large structural distortions of excited *** water molecules are adsorbed by C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7),it can subsequently emit green *** water-induced reversible emission switching is successfully used for optical security and information *** findings expand the under-standing of how the local coordination structure influences the photophysical mechanism in Sb^(3+)-doped metal halides and provide a novel method to control the STEs emission.

关键词： indium-based halides Sb^(3+)doping hydrogen bonding network optical anti-counterfeiting

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Artificial Intelligence Prediction of One-Part Geopolymer Compressive Strength for Sustainable Concrete

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 525-543页

作者： Mohamed Abdel-Mongy Mudassir Iqbal M.Farag Ahmed.M.Yosri Fahad Alsharari saif Eldeen A.S.Yousef Department of Civil Engineering College of EngineeringJouf UniversitySakaka72388Saudi Arabia Department of Civil Engineering University of Engineering and TechnologyPeshawar54890Pakistan Civil Engineering Department Faculty of EngineeringAl-Azhar UniversityCairo11884Egypt Civil Engineering Department Faculty of EngineeringAswan UniversityAswan81528Egypt

Alkali-activated materials/geopolymer(AAMs),due to their low carbon emission content,have been the focus of recent studies on ecological *** terms of performance,fly ash and slag are preferredmaterials for precursors for developing a one-part ***,determining the optimum content of the input parameters to obtain adequate performance is quite challenging and scarcely ***,in this study,machine learning methods such as artificial neural networks(ANN)and gene expression programming(GEP)models were developed usingMATLAB and GeneXprotools,respectively,for the prediction of compressive strength under variable input materials and content for fly ash and slag-based one-part *** database for this study contains 171 points extracted from literature with input parameters:fly ash concentration,slag content,calcium hydroxide content,sodium oxide dose,water binder ratio,and curing *** performance of the two models was evaluated under various statistical indices,namely correlation coefficient(R),mean absolute error(MAE),and rootmean square error(RMSE).In terms of the strength prediction efficacy of a one-part geopolymer,ANN outperformed *** and parametric analysis were also performed to identify the significant contributor to *** to a sensitivity analysis,the activator and slag contents had the most effects on the compressive strength at 28 *** water binder ratio was shown to be directly connected to activator percentage,slag percentage,and calcium hydroxide percentage and inversely related to compressive strength at 28 days and curing temperature.

关键词： Artificial intelligence techniques one-part geopolymer artificial neural network gene expression modelling sustainable construction polymers

Acute pancreatitis:pathogenesis and emerging therapies

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Journal of Pancreatology 2024年第1期7卷 10-20页

作者： saif Zaman Fred Gorelick Department of Internal Medicine Yale School of MedicineNew HavenCT 06511 Veteran’s Administration Healthcare System West HavenCT 06516 Department of Cell Biology Yale School of MedicineNew HavenCT 06511

Acute pancreatitis is a severe inflammatory disorder with limited treatment *** understanding of disease mechanisms has led to new and potential *** we summarize what we view as some of the most promising new therapies for treating acute pancreatitis,emphasizing the rationale of specific treatments based on disease *** pharmacologic interventions are *** explore potential treatment benefits and risks concerning reducing acute injury,minimizing complications,and improving long-term *** associated with acute pancreatitis initiation,perpetuation,and reconstitution are highlighted,along with potential therapeutic targets and how these relate to new treatments.

关键词： Acinar cell Acute pancreatitis Calcium signaling Transporters Treatment

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Micro-Computed Tomography Applications in Dentistry

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Open Journal of Stomatology 2024年第1期14卷 32-41页

作者： Ahmad Assari Maha Al Bukairi Reema Al saif Oral Maxillofacial Surgery & Diagnostic Sciences Department College of Medicine and Dentistry Riyadh Elm University Ri-yadh Saudi Arabia Orthodontist Ministry of Health First Health Cluster Riyadh Saudi Arabia Periodontist Ministry of Health Third Health Cluster Riyadh Saudi Arabia

Micro-computed tomography (MCT) encompasses two primary scanning options: ex-vivo and in-vivo imaging. Ex-vivo scanning involves the examination of extracted teeth or dental specimens, allowing for detailed analyses of the microarchitecture of mineralized tissue. By analyzing the microarchitecture of dental tissues, MCT can provide valuable information about bone density, porosity, and microstructural changes, contributing to a better understanding of disease progression and treatment outcomes. Moreover, MCT facilitates the quantification of dental parameters, such as bone volume, trabecular thickness, and connectivity density, which are crucial for evaluating the efficacy of dental interventions. This present study aims to comprehensively review and explore the applications of MCT in dentistry and highlight its potential in advancing research and clinical practice. The results depicted that the quantitative approach of MCT enhances the precision and reliability of dental research. Researchers and clinicians can make evidence-based decisions regarding treatment strategies and patient management, relying on quantifiable data provided by MCT. The applications of MCT in dentistry extend beyond research, with potential clinical implications in fields such as dental implantology and endodontics. MCT is expected to play an increasingly significant role in enhancing our understanding of dental pathologies, improving treatment outcomes, and ultimately, benefiting patient care in the field of dentistry.

关键词： Clinical Practice Dentistry Ex-Vivo Scanning Micro-Computed Tomography

在公司层面的不确性下进行研究和开发投资：来自沙特公司数据的证据

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在公司层面的不确性下进行研究和开发投资：来自沙特公司数据的证...

作者： saif ABDULLAH ABDULHAFEDH ABDULLAH 北京化工大学

学位级别：硕士

本研究探讨了源于两大全球性事件——2008年金融危机和COVID-19大流行——的不确定性中固有的多方面挑战和不可预测的经济动态。本研究旨在确定不确定性对沙特阿拉伯王国2007年至2020年间研究与开发(R&D)活动的影响程度,特别关注工业部... 详细信息

本研究探讨了源于两大全球性事件——2008年金融危机和COVID-19大流行——的不确定性中固有的多方面挑战和不可预测的经济动态。本研究旨在确定不确定性对沙特阿拉伯王国2007年至2020年间研究与开发(R&D)活动的影响程度,特别关注工业部门。沙特公司选择标准基于各种因素,包括王国最近的经济发展和工业部门在国家经济框架中的决定性作用,共选取了十五家在战略性分配研发预算方面领先的沙特公司。所需数据通过收集涵盖2007年至2020年期间公司的年度财务报告从研究人群中获取。方法上,使用描述性统计分析方法,通过STATA程序分析在沙特阿拉伯证券交易所上市的工业公司的数据,以描述研究的两个变量(独立变量和依赖变量)的现实情况,并理解其关系及其影响。进行了统计测试,结果表明研发投资和不确定性之间没有明显或直接的关系。相反,这种关系是复杂的,并受到研究所进行的具体背景或环境中不同方面的影响。一些公司在危机期间将研发视为推动增长和创新的战略要务,而其他公司则根据其财务表现采取短期的成本削减措施。R平方值在0到1(或0%到100%)之间,表示金融危机和COVID-19解释的研发投资平均波动百分比为13.22%。这表明这些因素仅占研发投资波动的一小部分。低R平方值确认了其他未研究的因素(财务表现变量)显著影响研发投资,占大部分(86.78%)的差异。基于金融危机和COVID-19危机的研发投资模型解释力有限,建议进一步研究以纳入更广泛的技术、环境、经济及其他因素,最终促进对研发与不确定性之间复杂关系的更全面理解。我们注意到相关系数为0.363611,表明变量之间的关系相对较弱。建议进行进一步研究,通过在研究样本中纳入更广泛的技术、环境、经济等因素,深化对研发与不确定性复杂关系的理解。

关键词：不确定性研发 2008年金融危机财务绩效新冠肺情