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Multiple Quantum Coherences(MQ) NMR and Entanglement Dynamics in the Mixed-Three-Spin XXX Heisenberg Model with Single-Ion Anisotropy

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Communications in Theoretical Physics 2016年第12期65卷 629-637页

作者： hamid arian zad Young Researchers and Elite Club Mashhad Branch Islamic Azad University

We analytically investigate Multiple Quantum(MQ) NMR dynamics in a mixed-three-spin(1/2,1,1/2)system with XXX Heisenberg model at the front of an external homogeneous magnetic field B. A single-ion anisotropy property ζ is considered for the spin-1. The intensities dependence of MQ NMR coherences on their orders(zeroth and second orders) for two pairs of spins(1,1/2) and(1/2,1/2) of the favorite tripartite system are obtained. It is also investigated dynamics of the pairwise quantum entanglement for the bipartite(sub)systems(1,1/2) and(1/2,1/2)permanently coupled by, respectively, coupling constants J_1 and J_2, by means of concurrence and fidelity. Then, some straightforward comparisons are done between these quantities and the intensities of MQ NMR coherences and ultimately some interesting results are reported. We also show that the time evolution of MQ coherences based on the reduced density matrix of the pair spins(1,1/2) is closely connected with the dynamics of the pairwise entanglement. Finally, we prove that one can introduce MQ coherence of the zeroth order corresponds to the pair spins(1,1/2) as an entanglement witness at some special time intervals.

关键词： multiple quantum coherence single-ion anisotropy concurrence entanglement witness

Transferring information through a mixed-five-spin chain channel

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Chinese Physics B 2016年第8期25卷 53-58页

作者： hamid arian zad Hossein Movahhedian Department of Physics Shahrood University of Technology

We initially introduce one-dimensional mixed-five-spin chain with Ising-XY model which includes mixture of spins-1/2 and spins-1. Here, it is considered that nearest spins（1, 1/2） have Ising-type interaction and nearest spins（1/2, 1/2）have both XY-type and Dzyaloshinskii–Moriya（DM） interactions together. Nearest spins（1, 1） have X X Heisenberg interaction. This system is in the vicinity of an external homogeneous magnetic field B in thermal equilibrium state. We promote the quantum information transmitting protocol verified for a normal spin chain with simple model（refer to Rossini D, Giovannetti V and Fazio R 2007 Int. J. Quantum Infor. 5 439）（widely in reference： Giovannetti V and Fazio R 2005 Phys. Rev. A 71 032314） by means of considering the suggested mixed-five-spin chain as a quantum communication channel for transmitting both qubits and qutrits ideally. Hence, we investigate some useful quantities such as quantum capacity and quantum information transmission rate for the system. Finally, we conclude that, when the DM interaction between spins（1/2, 1/2） increases the system is a more ideal channel for transmitting information.

关键词： Dzyaloshinskii-Moriya interaction XX Heisenberg interaction communication channel transmission rate

Magnetic Properties of an Antiferromagnetic Spin-1/2 XYZ Model in the Presence of Different Magnetic Fields: Finite-Size Effects of Inhomogeneity Property

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Communications in Theoretical Physics 2019年第10期71卷 1253-1260页

作者： hamid arian zad Azam Zoshki Moones Sabeti Young Researchers and Elite Club Mashhad BranchIslamic Azad UniversityMashhadIran Alikhanyan National Science Laboratory Alikhanian Br.20036YerevanArmenia

Magnetic and thermodynamic properties of the anisotropic XYZ spin-1/2 finite chain under both homogeneous and inhomogeneous magnetic fields are theoretically studied at low temperature. Using exact diagonalization method(ED), we study the magnetization, magnetic susceptibility, and specific heat of the model characterized in terms of the finite correlation length in the presence of three different magnetic fields including longitudinal, transverse, and transverse staggered magnetic fields. The magnetization, susceptibility, and the specific heat of the model are investigated under two conditions separately:(i) When the model is putted in the presence of homogeneous magnetic fields.(ii) When finite inhomogeneities are considered for all applied magnetic fields in the Hamiltonian. We show that for thefinite-size XYZ chains at low temperature, the evident magnetization plateaus gradually convert to their counterpart quasi-plateaus when the transverse magnetic field increases. Moreover, the influence of the transverse and staggered transverse magnetic fields, and their corresponding inhomogeneities on the magnetization process, magnetic susceptibility, and specific heat are reported in detail. Our exact results illustrate that by altering the inhomogeneity parameters,magnetization plateaus gradually convert to their counterpart quasi-plateaus. The specific heat manifests Schottky-type maximum, double-peak, and triple-peak, as well as, transformation between them by varying considered inhomogeneity parameters in the Hamiltonian.

关键词： spin chain magnetization susceptibility specific heat

A Decentralized and TCAM-Aware Failure Recovery Model in Software Defined Data Center Networks

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Computers, Materials & Continua 2025年第1期82卷 1087-1107页

作者： Suheib Alhiyari Siti Hafizah AB hamid Nur Nasuha Daud Department of Computer System and Technology University of MalayaKuala Lumpur50603Malaysia

Link failure is a critical issue in large networks and must be effectively *** software-defined networks(SDN),link failure recovery schemes can be categorized into proactive and reactive *** schemes have longer recovery times while proactive schemes provide faster recovery but overwhelm the memory of switches by flow *** SDN adoption grows,ensuring efficient recovery from link failures in the data plane becomes *** particular,data center networks(DCNs)demand rapid recovery times and efficient resource utilization to meet carrier-grade *** paper proposes an efficient Decentralized Failure Recovery(DFR)model for SDNs,meeting recovery time requirements and optimizing switch memory resource *** DFR model enables switches to autonomously reroute traffic upon link failures without involving the controller,achieving fast recovery times while minimizing memory *** employs the Fast Failover Group in the OpenFlow standard for local recovery without requiring controller communication and utilizes the k-shortest path algorithm to proactively install backup paths,allowing immediate local recovery without controller intervention and enhancing overall network stability and *** employs flow entry aggregation techniques to reduce switch memory *** of matching flow entries to the destination host’s MAC address,DFR matches packets to the destination switch’s MAC *** reduces the switches’Ternary Content-Addressable Memory(TCAM)***,DFR modifies Address Resolution Protocol(ARP)replies to provide source hosts with the destination switch’s MAC address,facilitating flow entry aggregation without affecting normal network *** performance of DFR is evaluated through the network emulator Mininet 2.3.1 and Ryu 3.1 as SDN *** different number of active flows,number of hosts per edge switch,and different network sizes,the proposed model outperformed vario

关键词： Software defined networking failure detection failure recovery restoration protection TCAM size

A Survey of Link Failure Detection and Recovery in Software-Defined Networks

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Computers, Materials & Continua 2025年第1期82卷 103-137页

作者： Suheib Alhiyari Siti Hafizah AB hamid Nur Nasuha Daud Department of Software Engineering Universiti MalayaKuala Lumpur50603Malaysia

Software-defined networking(SDN)is an innovative paradigm that separates the control and data planes,introducing centralized network *** is increasingly being adopted by Carrier Grade networks,offering enhanced networkmanagement capabilities than those of traditional ***,because SDN is designed to ensure high-level service availability,it faces additional *** of themost critical challenges is ensuring efficient detection and recovery from link failures in the data *** failures can significantly impact network performance and lead to service outages,making resiliency a key concern for the effective adoption of *** the recovery process is intrinsically dependent on timely failure detection,this research surveys and analyzes the current literature on both failure detection and recovery approaches in *** survey provides a critical comparison of existing failure detection techniques,highlighting their advantages and ***,it examines the current failure recovery methods,categorized as either restoration-based or protection-based,and offers a comprehensive comparison of their strengths and ***,future research challenges and directions are discussed to address the shortcomings of existing failure recovery methods.

关键词： Software defined networking failure detection failure recovery restoration protection

Thermospheric neutral wind studies over the equatorial region:A review

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Earth and Planetary Physics 2025年第1期9卷 81-100页

作者： Siti Syazwani Nasuha Idahwati Sarudin Nurul Shazana Abdul hamid Ahmad Fairuz Omar School of Physics Universiti Sains Malaysia11800 USMPulau PinangMalaysia Department of Applied Physics Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Space Science Centre(ANGKASA) Institute of Climate ChangesUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia

Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,particularly over the magnetic equator,have been a subject of study for several ***,despite the known importance of neutral winds,a comprehensive understanding and characterization of the winds is still *** ground-based and satellite missions have provided valuable information on the contribution of neutral winds to the global atmospheric ***,efforts in the global monitoring of neutral winds are still lacking,and the drivers behind the behavior of TNWs as well as their influence on the TIS remain *** address these knowledge gaps in the global circulation of TNWs,it is crucial to develop a deep understanding of the neutral wind characteristics over different *** low-latitude equatorial region in particular has been observed to exert complex influences on TNWs because of the unique effects of the Earth’s magnetic field at the dip *** neutral winds over this region will provide valuable insights into the unique dynamics and processes that occur in this region,thereby enhancing our understanding of their role in the overall dynamics of the ***,through empirical observations,an improved ability to accurately model and predict the behavior of this region can be *** review article addresses challenges in understanding equatorial winds by reviewing historical measurements,current missions,and the interactions of ionospheric and thermospheric phenomena,emphasizing the need for comprehensive measurements to improve global atmospheric dynamics and weather forecasting.

关键词： thermospheric neutral wind thermosphere-ionosphere system dip equator equatorial region

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha J.Holdsworth Alistair J.Gunn Laura Bennet hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

Fault Movement Potential of Marzanabad Area, North Alborz, Iran

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Open Journal of Geology 2015年第3期5卷 126-135页

作者： hamid Moghimi Mehran arian Ali Sorbi Department of Geology Science and Research Branch Islamic Azad University Tehran Iran Department of Geology Karaj Branch Islamic Azad University Karaj Iran

The major Quaternary faults of Marzanabad in the north Alborz can be classified based on their strikes into two sets: northwest and eastwest. In this paper, we use a model to evaluate their movement potential. Their theoretical model is based on the relationship between fault geometrical characteristics and regional tectonic stress field. The results show that Taleqan, Kandovan Chitan-Dozbon and Makaroud-Dalir fault zones are of the highest movement potential in the area. Also, the region where the fault zones have been intersected (northeastern part of study area) is prone to high seismicity;however, these fault zones don’t have high movement potentials.

关键词： Marzanabad Faults Alborz Movement Potential Iran

Molecular dynamics simulation of structure H clathrate-hydrates of binary guest molecules

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Journal of Natural Gas Chemistry 2011年第6期20卷 577-584页

作者： hamid Erfan-Niya hamid Modarress Department of Chemical Engineering Amirkabir University of Technology

Molecular dynamics （MD） simulations are performed to study the stability of structure H clathrate-hydrates of methane＋large-molecule guest substance （LMGS） at temperatures of 270, 273, 278 and 280 K under canonical （NVT-） ensemble condition in a 3×3×3 structure H unit cell replica with 918 TIP4P water molecules. The studied LMGS are 2-methylbutane （2-MB）, 2,3-dimethylbutane （2,3-DMB）, neohexane （NH）, methylcyclohexane （MCH）, adamantane and tert-butyl methyl ether （TBME）. In the process of MD simulation, achieving equilibrium of the studied system is recognized by stability in calculated pressure for NVT-ensemble. So, for the accuracy of MD simulations, the obtained pressures are compared with the experimental phase diagrams. Therefore, the obtained equilibrium pressures by MD simulations are presented for studying the structure H clathrate-hydrates. The results show that the calculated temperature and pressure conditions by MD simulations are consistent with the experimental phase diagrams. Also, the radial distribution functions （RDFs） of host-host, host-guest and guest-guest molecules are used to analysis the characteristic configurations of the structure H clathrate-hydrate.

关键词： structure H clathrate-hydrate methane+large-molecule guest substance molecular dynamics stability radial distribution function