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Dynamic resource allocation schemes for eMBB and URLLc services in 5G wireless networks

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Intelligent and converged Networks 2022年第2期3卷 145-160页

作者： Xianghui Han Kai Xiao Ruiqi Liu Xing Liu George c.Alexandropoulos Shi jin State Key Laboratory of Mobile Network and Mobile Multimedia Technology Shenzhen 518055Chinaand also with the Wireless Research InstituteZTE CorporationBeijing 100029China National Mobile communications Research Laboratory Southeast UniversityNanjing 210096China Department of Informatics and Telecommunications National and Kapodistrian University of AthensAthens 15784Greece

The fifth generation(5G)of wireless networks features three core use cases,namely ultra-reliable and low latency communications(URLLc),massive machine type communications(mMTc),and enhanced mobile broadband(eMBB).These use cases co-exist in many practical scenarios and compete for the same set of time and frequency resources,resulting in a natural trade-off in their *** this paper,a network supporting both URLLc and eMBB modes of operation is *** guarantee the ultra low latency requirement of URLLc,a dynamic resource allocation scheme indicated by a two-dimensional bitmap is *** approach is capable to achieve finer granularity as well as lower false cancellation rate compared to the state-of-the-art methods.A novel power control and indication method is also proposed to dynamically provide different power control parameters to the user equipment(UE),while guaranteeing the reliability requirement of URLLc and minimizing the impact to *** addition,we devise a dynamic selection mechanism(DSM)to accommodate diverse scenarios,which is empowered with load prediction to become more *** extensive system-level simulation results for eMBB-URLLc co-existence scenarios showcase that the perceived throughput of eMBB UEs is increased by 45.3%,while about 13.3% more UEs are enjoying URLLc services with at most 84% transmit power savings compared to the state-of-the-art methods.

关键词： the fifth generation(5G) co-existence enhanced mobile broadband(eMBB) multiplexing resource allocation power control ultra-reliable and low latency communications(URLLc) uplink

Experimental and Modeling Study on c_(2)H_(2)Oxidation and Aromatics Formation at 1.2 MPa

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Journal of Thermal Science 2023年第2期32卷 866-880页

作者： TIAN Zhenyu TIAN Dongxu jin Kairu cHNE jintao jin Zhihao LI Wang DU Lijun YANG Jiuzhong Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of chinese Academy of Sciences Beijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Oxidation of acetylene(c_(2)H_(2))has been investigated in a high-pressure jet-stirred reactor(HP-JSR)with equivalence ratiosΦ=0.5,1.0,2.0 and 3.0 in the temperature range of 650 K-900 K at 1.2 MPa.18 products and intermediates were analyzed qualitatively and quantitatively by gas chromatography(Gc)and gas chromatography-mass spectrometry(Gc-MS).Generally,withΦincreasing,the production of intermediates increases ***_(4),c_(2)H_(4),c_(2)H_(6),c_(3)H_(6)and c_(3)H_(8)were important intermediates,which were formed abundantly atΦ=*** light hydrocarbon intermediates could be an important reason for significant formation of cyclopentadiene,benzene,toluene and styrene atΦ=3.0.A detailed kinetic mechanism consisting of 299 species and 2041 reactions has been developed with reasonable predictions against the present data and previous results obtained at 0.1 *** to flux and sensitivity analysis,H and OH radicals play important roles in the consumption of c_(2)H_(2).The combinations among light hydrocarbons and their free radicals are the main generation pathways of aromatics.c_(3)H_(3),Ic_(4)H_(5)and Ac_(3)H_(5)are important precursors for the formation of *** comparing the results of atmospheric pressure and high pressure,it can be found that increasing the pressure is conducive to fuel consumption and aromatics generation.

关键词： acetylene high pressure oxidation jet-stirred reactor aromatics mechanism flux analysis sensitivity analysis

ZnO@Porous Media,Their PL and Laser Effect

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Journal of Materials Science & Technology 2008年第4期24卷 495-511页

作者： c.Bouvy Laboratory of Inorganic Materials chemistry The University of Namur(FUNDP)61 rue de BruxellesB-5000 NamurBelgium

Optoelectronic nanocomposites are a new class of materials, which exhibit very interesting and particular properties and attract a growing attention due to their potential applications in information storage and optoelectronic devices. Zinc oxide, ZnO, is one of the most interesting binary semiconductor （3.37 eV） with very important optical properties, which can be used in the fields such as short wavelength lasers, blue light emitting diodes, UV detectors, gas sensors, etc. This paper reviews the very recent progress in the prepa- ration of silica-based ZnO nanocomposites. After an introduction reviewing the theoretical background, the article will begin with a survey of the optical properties and the quantum size effect （QSE） of ZnO/SiO2 nanocomposites prepared by the inclusion of ZnO nanoclusters inside silica mesoporous materials. The second part will focus on one of the most interesting properties of ZnO/SiO2 nanocomposites, which is the random lasing effect after one- and two-photon excitation. The final part will deal with the introduction of ZnO nanoparticles inside microporous zeolites and the observation of QSE. For comparison, the photoluminescence （PL） and QSE properties of ZnS nanoparticles occluded in mesoporous media are also described. New potential applications will be discussed since short-wavelength devices are required by industry to design, for instance, new information storage supports and biolabelling devices.

关键词： ZnO nanoparticles Microporous and mesoporous materials Quantum size effect Random lasing effect

Phase Homogeneity and crystal Structure of Sb_(88)Te_(12) Synthesized by Melt-quench Method

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 441-446页

作者： c.Rangasami Department of Physics Erode Sengunthar Engineering College

Phase homogeneity and crystal structure of SbsaTe12 alloy synthesized by melt-quench method have been analyzed using X-ray diffraction （XRD） and Raman spectroscopy. Rietveld refinement of crystal structure of Sb8sTe12 has revealed the formation of SbsTe3 and Sb phases respectively with 11R and A7 structures （space group is R3m）. Phase fractions of the phases SbsTe3 and Sb have been determined to be 44.44% and 55.56% respectively. Raman spectrum of SbssTe12 has showed a highest intensity peak at 156 cm-1 and another peak at 151.1 cm-1, which correspond to Alg modes of SbsTe3 and element Sb, respectively. Analysis of Raman spectrum has substantiated the results obtained from structure refinement regarding the presence of two different phases.

关键词： SbssTe12 alloy Melt-quench method XRD Rietveld refinement Raman spectroscopy Multiphase formation

Effects of illness perception on negative emotions and fatigue in chronic rheumatic diseases:Rumination as a possible mediator

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World Journal of clinical cases 2022年第34期10卷 12515-12531页

作者： Yanxia Lu Xia jin Li-Wei Feng cSK Tang Michelle Neo Roger c Ho Department of Medical Psychology and Ethics School of Basic Medical SciencesCheeloo College of MedicineShandong UniversityJinan 250012Shandong ProvinceChina The Third Hospital of jinan Jinan 250132Shandong ProvinceChina college of Education for the Future Beijing Normal UniversityZhuhai 519087Guangdong ProvinceChina Department of Obstetrics and Gynecology National University of SingaporeThe Chinese University of Hong KongSingapore 117570Singapore Department of Psychological Medicine National University of SingaporeSingapore 119228Singapore

BAcKGROUND Illness perception has long been hypothesized to be linked to psychological well-b eing in patients with rheumatic diseases,although substantial evidence is lacking,and the contribution of ruminative coping style to this relationship is *** To investigate the roles of illness perception and rumination in predicting fatigue and negative emotions in patients with chronic rheumatic *** Illness perception,rumination,fatigue and negative emotions(***,anxiety and stress)were assessed by the Illness Perception Questionnaire-Revised,Stress Reactive Rumination Scale,Multidimensional Assessment of Fatigue,and the Depression,Anxiety and Stress Scale *** regression analysis,the Sobel test,and the bootstrap were used to identify the mediating effect of *** All five subscales of illness perception,including perceived illness identity,chronicity,cyclical nature,consequences and coherence of illness,were significantly associated with fatigue and negative *** mediational analysis,rumination was found to mediate three components of illness perception(the identity,cyclical nature and consequences of illness)and negative emotions/*** Perceived identity,cyclical nature,and consequences of illness are significantly associated with fatigue and negative emotions in patients with chronic rheumatic diseases and these associations are mediated by *** findings suggest that psychological intervention should target rumination to improve physical and emotional well-being of patients with chronic rheumatic diseases.

关键词： Fatigue Illness perception Negative emotions Rheumatoid arthritis Rumination Systemic lupus erythematosus

POSITRON LIFETIME STUDY OF THERMALLY INDUcED MIcROSTRUcTURAL cHANGES IN NISTARI SILK FIBER

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chinese Journal of Polymer Science 2003年第3期21卷 325-332页

作者： c.Ranganathaiah Department of Studies in Physics University of Mysore Manasagangotri Mysore-570 006 India

Positron lifetime measurements have been made in natural polymer-Nistari silk fibers as a function of isochronalannealing temperature in the range of 27℃ to 280℃. The variations in the positron results indicate the structural changesoccurring in the Nistari silk fibers and determine the glass transition temperature as 170℃. Activation energies weremeasured separately for the crystalline and amorphous regions indicating the versatility of the technique. These values areclose to the N--H bond dissociation energy, suggesting N--H bond dissociation as the most probable process occurringduring thermal treatment As an extension of the positron results, the molecular weight of the Nistari silk fibers wasdetermined to be 10.7×10~5 based on free volume, which lies within the range suggested for the silk fibers. There seems to bean indication that cross-linking changes the spiral structure of cotton fibers to network type. However, this needs to be validated by other techniques.

关键词： Nistari silk fiber Positronium Free volume Molecular weight Activation energy

Effect of multi-walled carbon nanotube addition on the microstructures and mechanical properties of Ti(c,N)-based cermets

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Journal of Advanced ceramics 2018年第1期7卷 58-63页

作者： P.WU S.c.LIU X.R.JIANG college of chemistry and Materials Science Longyan University

The surface modification of multi-walled carbon nanotubes(MWcNTs) was carried out using plasma treatment. The microstructures of the prepared cermets with different additions of MWcNTs were investigated by scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy dispersive X-ray analysis(EDX), and X-ray diffraction(XRD). Mechanical properties such as transverse rupture strength(TRS), fracture toughness(K_(Ic)), and hardness(HRA) were measured. The results showed that some reactive groups were successfully modified on the surface of MWcNTs, resulting in the improvement of dispersibility. Most of the amorphous carbons and impurities were peeled from the MWcNTs. Increasing MWcNT addition decreased the dissolution of tungsten, titanium, and molybdenum in the binder phase. The cermet with 0.5 wt% MWcNT addition showed the highest TRS and fracture toughness. The strengthening mechanisms were attributed to the finer grain size, the homogeneous microstructure, and the higher volume fraction of binder phase in the binder. The toughening mechanisms were characterized by bridging and pulling-out.

关键词： Ti(c,N)-based cermets microstructure mechanical property fracture toughness

Some studies on transient behaviours of sheath formation in dusty plasma with the effect of adiabatically heated electrons and ions

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Plasma Science and Technology 2017年第9期19卷 35-40页

作者： G c DAS Gyan Darshan Academy VIP RoadGuwahati-781022India

Based on quasipotential analysis, a plasma sheath is studied through the derivation of the Sagdeev potential equation in dusty plasma coexisting with adiabatically heated electrons and ions. Salient features as to the existence of sheaths are shown by solving the Sagdeev potential equation through the Runge–Kutta method, with appropriate consideration of adiabatically heated electrons and ions in the dynamical system. It has been shown that adiabatic heating of plasma sets a limit to the critical dust speed depending on the densities and Mach number, and it is believed that its role is very important to the sheath. One present problem is the contraction of the sheath region whereby dust grains levitated into the sheath lead to a crystallization similar to the formation of nebulons and are compressed to a larger chunk of the dust cloud by shrinking of the sheath. Our overall observations advance knowledge of sheath formation and are expected to be of interest in astroplasmas.

关键词： sheath heated dynamical Kutta Runge derivation shrinking coexisting grains compressed

The cross section calculation of 112Sn(α,γ)116Te reaction with different nuclear models at the astrophysical energy range

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Nuclear Science and Techniques 2017年第8期28卷 103-109页

作者： c. Yalcin Department of Physics Kocaeli University 41380 UmuttepeKocaeli Turkey

The theoretical cross section calculations for the astrophysical p process are needed because most of the related reactions are technically very difficult to be measured in the laboratory. Even if the reaction was measured,most of the measured reactions have been carried out at the higher energy range from the astrophysical ***, almost all cross sections needed for p process simulation have to be theoretically calculated or extrapolated to the astrophysical energies.^(112)Sn(α,γ)^(116)Te is an important reaction for the p process nucleosynthesis. The theoretical cross section of ^(112)Sn(α,γ)^(116)Te reaction was investigated for different global optical model potentials,level density, and strength function models at the astrophysically interested energies. Astrophysical S factors were calculated and compared with experimental data available in the EXFOR database. The calculation with the optical model potential of the dispersive model by Demetriou et al., and the back-shifted Fermi gas level density model and Brink-Axel Lorentzian strength function model best served to reproduce experimental results at an astrophysically relevant energy region. The reaction rates were calculated with these model parameters at the p process temperature and compared with the current version of the reaction rate library Reaclib and Starlib.

关键词：核反应模型天体物理学截面计算能量范围光学模型势模型参数计算函数模型能级密度