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Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： Khalil Ullah Song Jian Muhammad Naeem Ul Hassan Suliman Khan mohammad Babar Arshad Ahmad Shafiq Ahmad faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&IT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

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国际眼科杂志 2025年第1期25卷 17-23页

作者： Rozhin Kasiri Gholamreza Khataminia Ali Kasiri mohammad Sadegh Mirdehghan mohammad Armin Kasiri Infectious Ophthalmologic Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Islamic Azad University Tehran Medical Sciences Tehran ***Iran

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for *** was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes ***,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

关键词： risk factors congenital nasolacrimal duct obstruction children

Decoding molecular mechanisms:brain aging and Alzheimer's disease

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Neural Regeneration Research 2025年第8期20卷 2279-2299页

作者： Mahnoor Hayat Rafay Ali Syed Hammad Qaiser mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid Bashir Atta-ur-Rahman School of Applied Biosciences(ASAB) National University of Sciences and Technology(NUST)IslamabadPakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabadPakistan Department of Biological Sciences Faculty of Basic&Applied SciencesInternational Islamic University Islamabad(IIUI)IslamabadPakistan Department of Bioengineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia Department of Physiology College of MedicineKing Saud UniversityRiyadhSaudi Arabia Department of Neurology Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Mental Health Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Biosciences Commission on Science and Technology for Sustainable Development in the South(COMSATS University)IslamabadPakistan Department of Psychiatry The First Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Mental Health Institute of Hebei Medical University ShijiazhuangHebei ProvinceChina Department of Neurobiology and Behavior University of CaliforniaIrvineCAUSA Neuroscience Center King Fahad Specialist Hospital DammamDammamSaudi Arabia

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for *** aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's *** these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging *** these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect *** review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

关键词： Alzheimer’s disease brain aging cognitive health dementia molecular mechanisms neuronal activity neuroplasticity neurotransmission

Optimal Predictive Impedance Control in the Presence of Uncertainty for a Lower Limb Rehabilitation Robot

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Journal of Systems Science & Complexity 2020年第5期33卷 1310-1329页

作者： JALAEIAN-f.Mohsen fATEH mohammad Mehdi RAHIMIYAN Morteza Department of Electrical and Robotic Engineering Shahrood University of TechnologyShahroodIran

As an innovative concept,an optimal predictive impedance controlle is introduced here to control a lower limb rehabilitation robo in the presence of *** desired impedance law is considered to propose a conventional model-based impedance controller for the ***,external disturbances,model imperfection,and parameters uncertainties reduce the performance of the controller in *** order to cope with these uncertainties,an optimal predictive compensator is introduced as a solution for a proposed convex optimization problem,which is performed on a forward finite-length *** a result,the LLRR has the desired behavior even in an uncertain *** performance and efficiency of the proposed controller are verified by the simulation results.

关键词： Impedance control lower limb rehabilitation robots model predictive compensator optimal predictive impedance controller optimization in the presence of uncertainty

Resilience-oriented intentional islanding of reconfigurable distribution power systems

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 741-752页

作者： mohammad Hossein OBOUDI mohammad mohammadI mohammad RASTEGAR Department of Power and Control Engineering School of Electrical and Computer EngineeringShiraz UniversityShirazIran

The participation of distributed energy resources in the load restoration procedure,known as intentional islanding,can significantly improve the distribution system *** system reconfiguration can effectively alter islanding procedure and thus provide an opportunity to supply more demanded energy and reduce distribution system *** addition,high-impact events such as hurricanes and earthquakes may complicate the procedure of load restoration,due to the disconnection of the distribution system from the upstream grid or concurrent component *** paper presents a two-level method for intentional islanding of a reconfigurable distribution system,considering high-impact *** thefirst level,optimal islands are selected according to the graph model of the distribution *** the second level,an optimal power flow(OPf)problem is solved to meet the operation constraints of the islands by reactive power control and demand side *** proposed problem in the first level is solved by a combination of depth first search and particle swarm optimization *** OPf problem in the second level is solved in DIgSILENT *** proposed method is implemented in the IEEE 69-bus test system,and the results show the validity and effectiveness of the proposed algorithm.

关键词： Intentional islanding Active distribution system Distributed energy resource Distribution system reconfiguration Distribution system resilience

Remote ischemic conditioning approach for the treatment of ischemic stroke

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Neural Regeneration Research 2020年第6期15卷 1033-1034页

作者： Seyed mohammad Seyedsaadat David f.Kallmes Waleed Brinjikji Department of Radiology Mayo Clinic

Stroke is the leading cause of disability and death in North *** has been growing interest in identifying neuroprotective strategies to reduce ischemic burden in patients with acute ischemic ***,despite extensive clinical trials,no neuroprotective agent has been found for prevention of ischemic *** ischemic preconditioning(RIC)is a promising non-invasive strategy that has been proven to provide renal and cardioprotection and has recently found to have a potential broad application in the treatment of neurovascular disease,which has bee linked to its possible effects on the release and activation of endogenous neuroprotective substances against the ischemia/reperfusion injuries in experimental *** endogenous neuroprotection might vaccinate neural tissues against effects of acute IR following primary infarction *** of the method of RIC administration,through manual or automated blood pressure cuff,RIC procedure is inexpensive and easy to *** on the experimental and clinical data,application of RIC avoids possible adverse effects and interactions associated with chemical pharmacological *** previous clinical studies RIC was safe and associated with only minor transient adverse effects in few cases,including petechia and minor limb pain,which were mostly resolved shortly after completing the treatment.

关键词： prevention treatment Remote

Artificial ground freezing of underground mines in cold regions using thermosyphons with air insulation

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International Journal of Mining Science and Technology 2024年第5期34卷 643-654页

作者： Ahmad f.Zueter mohammad Zolfagharroshan Navid Bahrani Agus P.Sasmito Department of Civil and Resource Engineering Dalhousie UniversityHalifax B3H4R2Canada Department of Mining Engineering McGill UniversityMontreal H3A0E8Canada

Current practice of underground artificial ground freezing(AGf)typically involves huge refrigeration systems of large economic and environmental *** this study,a novel AGf technique is proposed deploying available cold wind in cold *** is achieved by a static heat transfer device called thermosyphon equipped with an air insulation layer.A refrigeration unit can be optionally integrated to meet additional cooling *** introduction of air insulation isolates the thermosyphon from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration *** design is demonstrated using well-validated mathematical models from our previous work based on two-phase enthalpy method of the ground coupled with a thermal resistance network for the *** Canadian mines are considered:the Cigar Lake Mine and the Giant *** results show that our proposed design can speed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake ***,a cooling load of 2.4 GWh can be saved at the Cigar Lake ***,this study provides mining practitioners with sustainable solutions of underground AGf.

关键词： Artificial ground freezing Underground mining Sustainable mining Thermosyphon Air insulation Cold regions

Global Practical Stabilization of Discrete-Time Switched Affine Systems via a General Quadratic Lyapunov function and a Decentralized Ellipsoid

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IEEE/CAA Journal of Automatica Sinica 2021年第11期8卷 1837-1851页

作者： mohammad Hejri Department of Electrical Engineering Sahand University of TechnologySahand New TownTabriz 51335-1996Iran

This paper addresses the problem of global practical stabilization of discrete-time switched affine systems via statedependent switching *** attempts have been made to solve this problem via different types of a common quadratic Lyapunov function and an *** classical results require either the quadratic Lyapunov function or the employed ellipsoid to be of the centralized *** some cases,the ellipsoids are defined dependently as the level sets of a decentralized Lyapunov *** this paper,we extend the existing results by the simultaneous use of a general decentralized Lyapunov function and a decentralized ellipsoid parameterized *** proposed conditions provide less conservative results than existing works in the sense of the ultimate invariant set of attraction *** different approaches are proposed to extract the ultimate invariant set of attraction with a minimum size,i.e.,a purely numerical method and a numerical-analytical *** the former,both invariant and attractiveness conditions are imposed to extract the final set of matrix *** latter is established on a principle that the attractiveness of a set implies its ***,the stability conditions are derived based on only the attractiveness property as a set of matrix inequalities with a smaller *** examples are presented to prove the satisfactory operation of the proposed stabilization methods.

关键词： Decentralized quadratic Lyapunov function decentralized ellipsoid discrete-time switched affine systems practical stabilization switching power converters

Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas f.Sadreev Yong Li Andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances