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Landslide inventory and susceptibility modelling using geospatial tools,in Hunza-Nagar valley,northern Pakistan

Journal of Mountain science 2018年第6期15卷 1354-1370页

作者： alam sher bacha Muhammad sHAFIQUE Harald van der WERFF National Centre of Excellanee in Geology University ofPeshawar Peshawar-25130 Pakistan Faculty of Geo-Information science and Earth Observation （ITC） University of Twente Ensehede 7500 AE The Netherlands

A comprehensive landslide inventory and susceptibility maps are prerequisite for developing and implementing landslide mitigation strategies. Landslide susceptibility maps for the landslides prone regions in northern Pakistan are rarely available. The Hunza-Nagar valley in northern Pakistan is known for its frequent and devastating landslides. In this paper, we have developed a landslide inventory map for Hunza-Nagar valley by using the visual interpretation of the sPOT-5 satellite imagery and mapped a total of 172 landslides. The landslide inventory was subsequently divided into modelling and validation data sets. For the development of landslide susceptibility map seven discrete landslide causative factors were correlated with the landslide inventory map using weight of evidence and frequency ratio statistical models. Four different models of conditional independence were used for the selection of landslide causative factors. The produced landslides susceptibility maps were validated by the success rate and area under curves criteria. The prediction power of the models was also validated with the prediction rate curve. The validation results shows that the success rate curves of the weight of evidence and the frequency models are 82% and 79%, respectively. The prediction accuracy results obtained from this study are 84% for weight of evidence model and 80% for the frequency ratio model. Finally, the landslide susceptibility index maps were classified into five different varying susceptibility zones. The validation and prediction result indicates that the weight of evidence and frequency ratio model are reliable to produce an accurate landslide susceptibility map, which may be helpful for landslides management strategies.

关键词： Landslides Inventory map susceptibility assessment Northern Pakistan

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Design and analysis of intrusion detection systems for wireless mesh networks

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Digital Communications and Networks 2022年第6期8卷 1068-1076页

作者： Fawaz s.al-Anzi P.O.Ox 5969 safat 13060 Computer Engineering DepartmentKuwait UniversityKuwait

Intrusion is any unwanted activity that can disrupt the normal functions of wired or wireless networks. Wireless mesh networking technology has been pivotal in providing an affordable means to deploy a network and allow omnipresent access to users on the Internet. A multitude of emerging public services rely on the widespread, high-speed, and inexpensive connectivity provided by such networks. The absence of a centralized network infrastructure and open shared medium makes WMNs particularly susceptible to malevolent attacks, especially in multihop networks. Hence, it is becoming increasingly important to ensure privacy, security, and resilience when designing such networks. An effective method to detect possible internal and external attack vectors is to use an intrusion detection system. although many Intrusion Detection systems (IDss) were proposed for Wireless Mesh Networks (WMNs), they can only detect intrusions in a particular layer. Because WMNs are vulnerable to multilayer security attacks, a cross-layer IDs are required to detect and respond to such attacks. In this study, we analyzed cross-layer IDs options in WMN environments. The main objective was to understand how such schemes detect security attacks at several OsI layers. The suggested IDs is verified in many scenarios, and the experimental results show its efficiency.

关键词： Wireless Mesh network Intrusi on detection Cross-layer security

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A phase-locked loop using EsO-based loop filter for grid-connected converter: performance analysis

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Control Theory and Technology 2021年第1期19卷 49-63页

作者： Baoling Guo seddik bacha Mazen alamir Julien Pouget school of Engineering.(HEs sO)Universily of Applied sciences and Arts of Western switzeland Sion1950 ValaisSwitzerland Institute of Engineering Grenoble University Grenoble AlpesCNRSG2Elab38000 GrenobleFrance Institute of Engineering Grenoble University Grenoble AlpesCNRSGIPSA-Lab38400 Saint Martin D'HeresFrance

An extended state observer(EsO)-based loop filter is designed for the phase-locked loop(PLL)involved in a disturbed grid-connected converter(GeC).This EsO-based design enhances the performances and robustness of the PLL,and,therefore,improves control performances of the disturbed ***,the EsO-based LF can be applied to PLLs with extra filters for abnormal grid *** unbalanced grid is particularly taken into account for the performance analysis.A tuning approach based on the well-designed PI controller is discussed,which results in a fair comparison with conventional PI-type *** frequency domain properies are quantitatively analysed with respeet to the control stability and the noises *** frequency domain analysis and simulation results suggesti that the performances of the generated EsO-based controllers are comparable to those of the PI control at low frequency,while have better ability to atenuate high-frequency measurement *** phase margin decreases slightly,but remains ***,experimental tests are conducted with a hybrid power hardwarein-the-loop benchmark,in which balanced/unbalanced cases are both *** obtained results prove the effectiveness of EsO based PLLs when applied to the disturbed GeC.

关键词： Grid-conected converters Grid disturbances Phase-locked loop Loop filter Extended state observer Tuning approach stability analysis Phase margin Noises attenuation Power hardware-in-the-loop(PHIL)test

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NUMERICal sIMULATION OF FLOWs FOR sECOND-ORDER VIsCOELAsTIC FLUID COUPLED WITH HEAT TRANsFER BY DIFFERENTIal QUADRATURE METHOD

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Journal of Hydrodynamics 2005年第2期17卷 209-215页

作者： al-sAIF A.s.J. shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

The problem of two-dimensional steady flow of an incompressible second-order viscoelastic fluid coupled with heat transfer between parallel plates was considered. A viscous dissipation function was included in the energy equation. When the elastic property of the fluid is weaker, the zeroth-order and first-order approximate governing equations were obtained by means of the perturbation method. To understand the behavior of flow near the tube wall, the half-domain was divided into two sub-domains, in which one is a thin layer near the wall called the inner domain and the remainder is called the outer domain. The governing equations in the inner domain and in the outer domain were discretized respectively by using the Differential Quadrature Method (DQM). The matching conditions at the interface between the inner and outer domains were presented. An iterative method for solving these discretized equations was given in this paper. The numerical results obtained agree with existing results.

关键词： momentum equations heat equation second-order viscoelastic fluid Differential Quadrature Method (DQM)

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spectral Hole Burning via Kerr Nonlinearity

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Communications in Theoretical Physics 2015年第10期64卷 473-478页

作者： Anwar ali Khan M.s.Abdul Jabar M.Jalaluddin Bakht Amin bacha Iftikhar Ahmad Department of Physics University of Malakand

spectral hole burning is investigated in an optical medium in the presence of Doppler broadening and Kerr nonlinearity. The Kerr nonlinearity generates coherent hole burning in the absorption spectrum. The higher order Kerr nonlinearity enhances the typical lamb dip of the hole. Normal dispersion in the hole burning region while steep anomalous dispersion between the two hole burning regions also enhances with higher order Kerr effect. A large phase shift creates large delay or advancement in the pulse propagation while no distortion is observed in the pulse. These results provide significant steps to improve optical memory, telecom devices, preservation of information and image quality.

关键词： spectral hole burning Kerr nonlinearity Doppler br

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Revisiting cerebral endothelial cells in alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： alzheimer Aβ cerebral

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A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant

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Dynamical analysis and anti-synchronization of a new 6D model with self-excited attractors

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Applied Mathematics(A Journal of Chinese Universities) 2023年第1期38卷 27-43页

作者： saad Fawzi al-Azzawi Ahmed s.al-Obeidi Department of Mathematics College of Computer Science and MathematicsUniversity of MosulMosul 41002Iraq

A novel 6D dissipative model with an unstable equilibrium point is introduced *** of the dynamic characteristics of the proposed model were explored via analyses and numerical simulations including critical points,stability,Lyapunov exponents,time phase portraits,and circuit ***,anti-synchronization phenomena were implemented on the new ***,the error dynamics is ***,four different controllers are adopted to stabilize this error relying on the nonlinear control technique with two main ways:linearization and Lyapunov stability *** comparison with previous works,the present controllers realize anti-synchronization based on another method/linearization ***,a comparison between the two ways was *** simulation results show the effectiveness and accuracy of the first analytical strategy.

关键词： 6D hyperchaotic system self-excited attractor anti-synchronization Lyapunov stability theory

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Dual-Wavelength Passively Q-switched Ytterbium-Doped Fiber Laser Based on aluminum Oxide Nanoparticle saturable Absorbers

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Chinese Physics Letters 2017年第11期34卷 24-27页

作者： s.K.M.al-Hayali s.selleri A.H.al-Janabi Institute of Laser for Postgraduate studies University of Baghdad Department of Information Engineering Parma University

We report on generation of a dual-wavelength, all-fiber, passively Q-switched ytterbium-doped fiber laser using aluminum oxide nanoparticle （al2O3-NP） thin film. A thin film of al2O3 was prepared by embedding al2O3-NPs into a polyvinyl alcohol （PVA） as a host polymer, and then inserted between two fiber ferrules to act as a saturable absorber （sA）. By incorporating the al2O3-PVA sA into the laser cavity, a stable dual-wavelength pulse output centered at 1050 and 1060.7nm is observed at threshold pump power of 80mW. As the pump power is gradually increased from 80 to 300mW, the repetition rate of the generated pulse increases from 16.23 to 59 kHz, while the pulse width decreases from 19 to 6μs. To the best of our knowledge, this is the first demonstration for this type of sA operating in the 1 μm region.

关键词： sA Dual-Wavelength Passively Q-switched Ytterbium-Doped Fiber Laser Based on aluminum Oxide Nanoparticle saturable Absorbers

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spatial-dependent probe transmission based high-precision two-dimensional atomic localization

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Communications in Theoretical Physics 2021年第4期73卷 69-74页

作者： Muhammad Idrees Humaira Kalsoom Bakth Amin bacha Arif Ullah Li-Gang Wang Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310027China Quantum Optics and Quantum Information Research Group Department of PhysicsUniversity of MalakandChakdara Dir(L)Khyber PakhtunkhwaPakistan Department of Mathematics Zhejiang Normal UniversityJinhua 321004China

Herein,we propose a scheme for the realization of two-dimensional atomic localization in aλ-type three-level atomic medium such that the atom interacts with the two orthogonal standing-wave fields and a probe *** of the spatially dependent atom-field interaction,the information about the position of the atom can be obtained by monitoring the probe transmission spectra of the weak probe field for the first time.A single and double sharp localized peaks are observed in the one-wavelength *** have theoretically archived high-resolution and high-precision atomic localization within a region smaller thanλ/25×λ/*** results may have potential applications in the field of nano-lithography and advance laser cooling technology.

关键词： 2D atomic localization probe transmission spectra standing-wave fields three-level atomic medium

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