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Modulation Recognition with Frequency Offset and Phase Offset over Multipath Channels

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中国通信:英文版 2023年第10期20卷 58-69页

作者： Mingqian Liu Zhaoxi Wen Yunfei Chen Ming Li State Key Laboratory of Integrated Service Networks Xidian UniversityShaanxiXi’an 710071China Department of Engineering University of DurhamSouth RoadDH13LEDurhamUK Guilin Changhai Development Co. LtdGuangxiGuilin 541001China

Modulation recognition becomes unreliable at low signal-to-noise ratio(SNR)over fading channel.A novel method is proposed to recognize the digital modulated signals with frequency and phase offsets over multi-path fading channels in this *** method can overcome the effects of phase offset,Gaussian noise and multi-path *** achieve this,firstly,the characteristic parameters search is constructed based on the cyclostationarity of received signals,to overcome the phase offset,Gaussian white noise,and influence caused by multi-path ***,the carrier frequency of the received signal is estimated,and the maximum characteristic parameter is searched around the integer multiple carriers and their ***,the modulation types of the received signal with frequency and phase offsets are classified using decision *** results demonstrate that the performance of the proposed method is better than the traditional methods when SNR is over 5dB,and that the proposed method is robust to frequency and phase offsets over multipath channels.

关键词： cyclic characteristics frequency and phase offset multi-path channels modulation recognition

Impact of estuarine reclamation projects on saltwater intrusion and freshwater resource

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Journal of Oceanology and Limnology 2023年第1期41卷 38-56页

作者： Hanghang LU Jianrong ZHU Qing CHEN Ming LI Shunqi PAN Shenliang CHEN CCCC National Engineering Research Center of Dredging Technology and Equipment Co. Ltd.Shanghai 200082China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China Civil Engineering and Industrial Design School of EngineeringLiverpool UniversityLiverpool L693GHUK Hydro-environmental Research Centre School of EngineeringCardiff UniversityCardiff CF243AAUK

Estuarine projects can change local topography and influence water transport and saltwater *** Changjiang(Yangtze)River estuary is a multichannel estuary,and four major reclamation projects have been implemented in the Changjiang River estuary in recent years:the Xincun Shoal reclamation project(RP-XCS),the Qingcao Shoal reclamation project(RP-QCS),the Eastern Hengsha Shoal reclamation project(RP-EHS),and the Nanhui Shoal reclamation project(RP-NHS).The effects of the four reclamation projects and each project on the saltwater intrusion and water resources in the Changjiang River estuary were simulated in a 3D numerical *** show that for a multichannel estuary,local reclamation projects change the local topography and water diversion ratio(WDR)between channels and influence water and salt transport and freshwater utilization in the *** spring tide,under the cumulative effect of the four reclamation projects,the salinity decreases by approximately 0.5in the upper reaches of the North Branch and increases by 0.5-1.0 in the middle and lower reaches of the North *** the North Channel,the salinity decreases by approximately *** the North Passage,the salinity increases by *** the South Passage,the salinity increases by approximately 0.5 in the upper reaches and decreases by 0.2-0.5 on the north side of the middle and lower *** neap tide,the cumulative effects of the four reclamation projects and the individual projects are similar to those during spring tide,but there are some *** effects of an individual reclamation project on WDR and saltwater intrusion during spring and neap tides are simulated and analyzed in *** cumulative effect of the four reclamation projects favors freshwater usage in the Changjiang River estuary.

关键词： reclamation projects saltwater intrusion freshwater resources numerical model Changjiang River estuary

Reservoir stress path and induced seismic anisotropy： results from linking coupled fluid-flow/geomechanical simulation with seismic modelling

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Petroleum Science 2016年第4期13卷 669-684页

作者： D.A.Angus Q.J.Fisher J.M.Segura J.P.Verdon J.-M.Kendall M.Dutko A.J.L.Crook School of Earth and Environment University of LeedsLeeds UK Formerly School of Earth and Environment University of Leeds Leeds UK Department of Earth Sciences University of Bristol BristolUK Rockfield Software ltd. Swansea UK Three Cliffs Geomechanics Swansea UK Repsol Madrid Spain ESG Solutions Kingston Canada

We present a workflow linking coupled fluid-flow and geomechanical simulation with seismic modelling to predict seismic anisotropy induced by non-hydrostatic stress changes. We generate seismic models from coupled simulations to examine the relationship between reservoir geometry, stress path and seismic anisotropy. The results indicate that geometry influences the evolution of stress,which leads to stress-induced seismic anisotropy. Although stress anisotropy is high for the small reservoir, the effect of stress arching and the ability of the side-burden to support the excess load limit the overall change in effective stress and hence seismic anisotropy. For the extensive reservoir, stress anisotropy and induced seismic anisotropy are high. The extensive and elongate reservoirs experience significant compaction, where the inefficiency of the developed stress arching in the side-burden cannot support the excess *** elongate reservoir displays significant stress asymmetry,with seismic anisotropy developing predominantly along the long-edge of the reservoir. We show that the link betweenstress path parameters and seismic anisotropy is complex,where the anisotropic symmetry is controlled not only by model geometry but also the nonlinear rock physics model used. Nevertheless, a workflow has been developed to model seismic anisotropy induced by non-hydrostatic stress changes, allowing field observations of anisotropy to be linked with geomechanical models.

关键词： Coupled fluid-flow/geomechanics Reservoir characterization Seismic anisotropy Stress path

Atypical small acinar proliferation and its significance in pathological reports in modern urological times

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Asian Journal of Urology 2022年第1期9卷 12-17页

作者： Georgios Tsampoukas Victor Manolas Dominic Brown Athanasios Dellis Konstantinos Deliveliotis Mohamad Moussa Athanasios Papatsoris Department of Urology Princess Alexandra HospitalHarlowUK U-merge ltd.(Urology for Emerging Countries) LondonUK Department of Urology Broomfield HospitalChelmsfordUK Department of Urology and General Surgery Areteion HospitalAthensGreece 2nd Department of Urology School of MedicineSismanoglio HospitalNational and Kapodistrian University of AthensAthensGreece Chairman of Surgery&Urology Department Lebanese University&Zahraa HospitalUniversity Medical CenterBeirutLebanon

Atypical small acinar proliferation is a histopathological diagnosis of unspecified importance in prostate needle-biopsy reports,suggestive but not definitive for *** terminology corresponds to some uncertainty in the biopsy report,as the finding might represent an underlying non-cancerous pathology mimicking cancer or an under-sampled prostate cancer ***,traditional practice favors an immediate repeat ***,in modern urological times,the need of urgent repeat biopsy is being challenged by some authors as in the majority of cases,the grade of cancer found in subsequent biopsy is reported to be low or the disease to be *** the other hand,high risk disease cannot be excluded,whereas no clinical or pathological factors can predict the final *** this review,we discuss the significance of the diagnosis of atypical small acinar proliferation in the biopsy report,commenting on its importance in modern urological practice.

关键词： Prostate cancer Repeat biopsy Significant cancer Grade Atypical small cell proliferation Lesion suspicious for cancer

Optimising soft tissue in-growth in vivo in additive layer manufactured osseointegrated transcutaneous implants

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Biomaterials Translational 2022年第4期3卷 243-249页

作者： Elena Giusto Gordon Blunn Roberta Ferro de Godoy Chaozong Liu Catherine Pendegrass Institute of Orthopaedic&Musculoskeletal Science University College LondonRoyal National Orthopaedic HospitalStanmoreUK Barts and the London School of Medicine and Dentistry Queen Mary University LondonLondonUK School of Pharmacy and Biomedical Sciences University of PortsmouthPortsmouthUK Writtle University College WrittleUK

Osseointegrated transcutaneous implants could provide an alternative and improved means of attaching artificial limbs for amputees,however epithelial down growth,inflammation,and infections are common failure modalities associated with their *** overcome these problems,a tight seal associated with the epidermal and dermal adhesion to the implant is *** could be achieved with specific biomaterials(that mimic the surrounding tissue),or a tissue-specific design to enhance the proliferation and attachment of dermal fibroblasts and *** intraosseous transcutaneous amputation prosthesis is a new device with a pylon and a flange,which is specifically designed for optimising soft tissue *** the flange has been fabricated using traditional machining techniques,however,the advent of additive layer manufacturing(ALM)has enabled 3-dimensional porous flanges with specific pore sizes to be used to optimise soft tissue integration and reduce failure of osseointegrated transcutaneous *** study aimed to investigate the effect of ALM-manufactured porous flanges on soft tissue ingrowth and attachment in an in vivo ovine model that replicates an osseointegrated percutaneous *** 12 and 24 weeks,epithelial downgrowth,dermal attachment and revascularisation into ALM-manufactured flanges with three different pore sizes were compared with machined controls where the pores were made using conventional *** pore sizes of the ALM flanges were 700,1000 and 1250μ*** hypothesised that ALM porous flanges would reduce downgrowth,improve soft tissue integration and revascularisation compared with machined *** results supported our hypothesis with significantly greater soft tissue integration and revascularisation in ALM porous flanges compared with machined controls.

关键词： in-vivo model ITAP orthopaedic implants osseointegrated transcutaneous implants

Dielectric behaviours of bio-derived epoxy resins from cashew nutshell liquid

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High Voltage 2021年第2期6卷 255-263页

作者： Mulan Mu Alun Vaughan Department of Electronics and Computer Science Tony Davies High Voltage LaboratoryUniversity of SouthamptonSouthamptonUK Novel Polymer Technology Section TWI LtdCambridgeUK

In this study,four commercially available bio-derived epoxy systems(extracted from cashew nutshell liquid)were prepared and *** glass transition temperature(Tg),dielectric spectroscopy,DC conductivity and breakdown properties of these epoxy resins were *** scanning calorimetry(DSC)demonstrated that the T_(g) of the investigated systems ranged from 67 to 122°*** DC conductivity was very low(<10^(-16) S cm^(-1))and comparable to the conventional dielectrics at room temperature(RT).However,all systems showed a strong temperature dependence of the electrical conductivity and exhibited sharp increase around their respective T_(g).Arrhenius analysis led to activation energy,E_(a),values around 1 eV;higher E_(a) values were observed in systems with a lower T_(g).Dielectric spectroscopy revealed a flat and low response at temperature below T_(g).However,both the real and imaginary permittivity increased with decreasing frequency at mid to low frequencies as the temperatures approached T_(g).The variations of AC breakdown strength of all samples were not statistically significant,but the DC breakdown strength of sample 2503Aþ2002B was higher than the others,which might be due to reduced charge transport in this *** results indicate that novel bio-derived epoxy systems from renewable sources are potential alternatives for traditional petroleum-based epoxy systems in certain insulation applications.

关键词： conductivity resins liquid

Significant Lifetime Enhancement in QLEDs by Reducing Interfacial Charge Accumulation via Fluorine Incorporation in the ZnO Electron Transport Layer

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Nano-Micro Letters 2022年第12期14卷 432-446页

作者： Dong Seob Chung Tyler Davidson-Hall Giovanni Cotella Quan Lyu Peter Chun Hany Aziz Department of Electrical and Computer Engineering Waterloo Institute for NanotechnologyUniversity of Waterloo200 University Avenue WestWaterlooON N2L 3G1Canada Ipswich Research Centre Huawei Technologies Research&Development(UK)Ltd.Phoenix House(B55)Adastral ParkIpswich IP53REUK Ottawa IC Laboratory Huawei Canada19 Allstate ParkwayMarkhamON L3R 5B4Canada

ZnO nanoparticles are widely used for the electron transport layers(ETLs)of quantum dots light emitting devices(QLEDs).In this work we show that incorporating fluorine(F)into the ZnO ETL results in significant enhancement in device electroluminescence stability,leading to LT50 at 100 cd m^(−2) of 2,370,000 h in red QLED,47X longer than the control devices.X-ray photo-electron spectroscopy,time-of-flight secondary ion mass spectroscopy,photoluminescence and electrical measurements show that the F passivates oxygen vacancies and reduces electron traps in *** photoluminescence versus bias measurements and capacitance-voltage-luminance measurements reveal that the CF4 plasma-treated ETLs lead to increased electron concentration in the QD and the QD/hole transport layer interface,subsequently decreasing hole accumulation,and hence the higher *** findings provide new insights into the critical roles that optimizing charge distribution across the layers play in influencing stability and present a novel and simple approach for extending QLED lifetimes.

关键词： Colloidal quantum dots Quantum dots light emitting device Device stability Zinc oxide nanoparticles Fluorine

Mechanical behavior predictions of additively manufactured microstructures using functional Gaussian process surrogates

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npj Computational Materials 2021年第1期7卷 720-730页

作者： Robert Saunders Celia Butler John Michopoulos Dimitris Lagoudas Alaa Elwany Amit Bagchi US Naval Research Laboratory WashingtonDCUSA Texas A&M University College StationTXUSA Synopsys Northern Europe ltd ExeterUK University of Exeter ExeterUK

Relational linkages connecting process,structure,and properties are some of the most sought after goals in additive manufacturing(AM).This is desired especially because the microstructural grain morphologies of AM components can be vastly different than their conventionally manufactured ***,data collection at the microscale is ***,this work describes and demonstrates a methodology to link microstructure morphology to mechanical properties using functional Gaussian process surrogate models in a directed graphical network capable of achieving near real-time property predictions with single digit error magnitudes when predicting full stress–strain histories of a given *** methodology is presented and demonstrated using computationally generated microstructures and results from crystal plasticity simulations on those *** surrogate model uses grain-level microstructural descriptors rather than whole microstructure descriptors so that properties of new,arbitrary microstructures can be *** developed network has the potential to scale to predict mechanical properties of grain structures that would be infeasible to simulate using finite element methods.

关键词： grain microstructure additive

Measurement and quantification of caking in excipients and food products with emphasis on the non-homogeneous interaction with ambient moisture

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Particuology 2021年第3期19卷 75-83页

作者： Katrina Brockbank Brian Armstrong Jamie Clayton Freeman Technology ltd 1 Miller CourtSevern DriveTewkesburyGloucestershireGL208DNUK

Whilst caking occurs via several different mechanisms,absorption and migration of moisture is frequently the most dominant mechanism within the food and pharmaceutical *** understanding the propensity to cake is important for minimising down-stream process issues,however most characterisation techniques assume that moisture induced caking occurs homogenously through the sample resulting in a uniformly caked powder *** this study,the effect of moisture induced caking on powder flowability was investigated using powder *** materials,including skimmed milk powder(SMP)and sulphated methyl ester(SME)were stored for several days under controlled humidity *** flow energies,a measure of the resistance to flow,were measured at 24 h intervals using an FT4 Powder *** the energy is measured as a function of the bed height,variations in the powder bed are also *** results demonstrated that caking does not always occur uniformly,instead a caked region(or crust)forms at the air-powder interface and then progresses through the powder ***,the strength of this caked region was shown to increase over several days before stabilising.

关键词： Powder Caking Crust formation Powder rheometry Relative humidity