检索结果-南通市图书馆

A Numerical Study of Temporal Mixing Layer with Three-Dimensional Mortar Spectral Element Method

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2011年第6期28卷 187-189页

作者： ZHANG Xu LIU Jin-Hong jonathan W.N Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900 Mechanical Department University of WyomingLaramieUSA

We investigate a set of well-posed interface conditions of viscous fluxes of Navier–Stokes equations,extend them to three-dimensional Navier–Stokes equations and successfully study a temporally turbulent mixing *** evolution of a large vortex structure and the non-dimensional statistical quantities in the mixing layer are numerically *** span-wise energy spectrum of the mixing layer exhibits wide band features,which means that the simulation generates the desired amount of small *** results show that too many small scales are present due to insufficient dissipation and the amount of large scales is low,indicating too much dissipation for large-scale structures.

关键词： layer mixing dissipation

Formadinium Cation Doping Stabilized Ultra-deep-blue Lead Halide Perovskite Nanocrystal Light-emitting Diodes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第3期40卷 556-560页

作者： Pui Kei KO jonathan E.HALPERT Department of Chemistry The Hong Kong University of Science and TechnologyKowloonHong Kong 999077P.R.China

The halide migration effect in mixed-halide lead-based perovskite is a serious problem hindering the development of its display *** this study,we have successfully addressed this issue by reporting formadinium(FA)doped mixed-halide perovskite nanocrystals(NCs)with ultra-deep-blue emission of 450 nm,narrow bandwidth of 16 nm,and a high photoluminescence quantum yield(PLQY)of 66%.The perovskite nanocrystal light-emitting diodes(NC-LEDs)using this nanocrystal as an active layer achieved a maximum external quantum efficiency(EQE)of 0.32%,30-fold improved compared to that of pristine and stable electroluminescence(EL)spectra at 450 nm under a 4.9–8.0 V *** findings demonstrate the potential of our approach in developing stable and efficient deep blue perovskite NC-LEDs.

关键词： Halide perovskite Light-emitting diode Deep-blue

Organic-inorganic halide perovskites for memristors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2023年第9期44卷 39-46页

作者： Memoona Qammar Bosen Zou jonathan E.Halpert Department of Chemistry Hong Kong University of Science and Technology(HKUST)Clear Water Bay RoadKowloon 999077Hong Kong SARChina

Organic-inorganic halides perovskites(OHPs)have drawn the attention of many researchers owing to their astonishing and unique optoelectronic *** have been extensively used for photovoltaic applications,achieving higher than 26%power conversion efficiency to *** materials have potential to be deployed for many other applications beyond photovoltaics like photodetectors,sensors,light-emitting diodes(LEDs),and *** address the looming challenge of Moore’s law and the Von Neumann bottleneck,many new technologies regarding the computation of architectures and storage of information are being extensively *** the discovery of the memristor as a fourth component of the circuit,many materials are explored for memristive ***,researchers have advanced the exploration of OHPs for memristive *** materials possess promising memristive properties and various kinds of halide perovskites have been used for different applications that are not only limited to data storage but expand towards artificial synapses,and neuromorphic *** we summarize the recent advancements of OHPs for memristive applications,their unique electronic properties,fabrication of materials,and current progress in this field with some future perspectives and outlooks.

关键词： organic-inorganic halide perovskites resistive switching memristors

Genotypic,size and morphological diversity of virioplankton in a deep oligomesotrophic freshwater lake(Lac Pavin,France)

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2017年第3期29卷 48-59页

作者： jonathan Colombet Agnès Robin Télesphore Sime-Ngando Laboratory Microorganisms:Oenome and Environment Clermont University Blaise PascalUMR CNRS 602324 avenue des LandaisBP 80026F-63171 AubiereFrance CIRAD UMR Eco&Sols2 place Viala34060 Montpellier Cedex 1France

We examined changes in morphological and genomic diversities of viruses by means of transmission electronic microscopy and pulsed field gel electrophoresis （PFGE） over a nine-month period （April-December 2005） at four different depths in the oligomesotrophic Lac Pavin. We found that the majority of viruses in this lake belonged to the family of Siphouiridae or were untailed, with capsid sizes ranging from 30 to 60 nm, and exhibited genome sizes ranging from 15 to 45 kb. On average, 12 different genotypes dominated each of the PFGE fingerprints. The highest genomic viral richness was recorded in summer （mean = 14 bands per PFGE fingerprint） and in the epilimnion （mean = 13 bands per PFGE fingerprint）. Among the physico-chemical and biological variables considered, the availability of the hosts appeared to be the main factor regulating the variations in the viral diversity.

关键词： VirusLac PavinDynamicMorphological diversity Genomic diversity

On the calibration of a shear stress criterion for rock joints to represent the full stress-strain profile

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 379-392页

作者： Akram Deiminiat jonathan D.Aubertin Yannic Ethier Department of Construction Engineering École de Technologie Supérieure(ÉTS)MontréalCanada

Conventional numerical solutions developed to describe the geomechanical behavior of rock interfaces subjected to differential load emphasize peak and residual shear *** detailed analysis of preand post-peak shear stress-displacement behavior is central to various time-dependent and dynamic rock mechanic problems such as rockbursts and structural instabilities in highly stressed *** complete stress-displacement surface(CSDS)model was developed to describe analytically the pre-and post-peak behavior of rock interfaces under differential *** formulations of the CSDS model required extensive curve-fitting iterations which limited its practical applicability and transparent integration into engineering *** present work proposes modifications to the CSDS model aimed at developing a comprehensive and modern calibration protocol to describe the complete shear stressdisplacement behavior of rock interfaces under differential *** proposed update to the CSDS model incorporates the concept of mobilized shear strength to enhance the post-peak ***’s concepts of joint roughness coefficient(JRC)and joint compressive strength(JCS)are incorporated to facilitate empirical estimations for peak shear stress and normal closure ***/uniaxial compression test and direct shear test results are used to validate the updated model and exemplify the proposed calibration *** results illustrate that the revised model successfully predicts the post-peak and complete axial stressestrain and shear stressedisplacement curves for rock joints.

关键词： Full shear profile Post-peak shear behavior Rock joint Joint roughness coefficient(JRC) Axial stress-strain curve

Epidemiology regarding penile prosthetic surgery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2020年第1期22卷 2-7页

作者： Jose A Saavedra-Belaunde jonathan Clavell-Hernandez Run Wang Department of Surgery/Division of Urology University of Texas Medical Science Center at HoustonHoustonTX 77030USA St.Joseph's Medical Center HoustonTX 77002USA

With the onset of a metabolic syndrome epidemic and the increasing life expectancy,erectile dysfunction(ED)has become a more common *** incidence and prevalence increase,the medical field is focused on providing more appropriate *** is common knowledge that ED is a chronic condition that is also associated with a myriad of other *** such as aging,diabetes mellitus,hypertension,obesity,prostatic hypertrophy,and prostate cancer,among others,have a direct implication on the onset and progression of *** and recognition of risk factors may help clinicians recognize and properly treat patients suffering from *** of the most reliable treatments for ED is penile prosthetic *** the introduction of the penile prosthesis(PP)in the early seventies,this surgical procedure has improved the lives of thousands of men,with reliable and satisfactory *** aim of this review article is to characterize the epidemiology of men undergoing penile prosthetic surgery,with a discussion about the most common conditions involved in the development of ED,and that ultimately drive patients into electing to undergo PP placement.

关键词： erectile dysfunction penile prosthesis prosthetic surgery

Soil microbial biomass and population in response to seasonal variation and age in Gmelina arborea plantations in south-western Nigeria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2012年第2期23卷 253-260页

作者： jonathan C. Onyekwelu Department of Forestry and Wood Technology Federal University of Technology Akure P.M.B. 704 Akure Nigeria

We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15 and 15-30 cm from plantations of six different ages during the rainy season, dry seasons, and their transitions. We used plate count and fumigation-extraction methods to determine microbe population and microbial biomass carbon （MB-C） and nitrogen （MB-N）, respectively. Plantation age did not affect microbial indices, implying a non-significant effect of plantation development on microbial communities. It could also imply that soil microbial indices had already stabilized in the sampled plantations. Seasonal variation and soil depth had significant effects on microbial indices. At 0-15 cm soil depth, mean MB-C increased from 50.74 μg·g^-1 during the peak of the dry season （i.e. March） to 99.58μg·g-1 during the peak of the rainy season （i.e. September）, while it increased from 36.22μg·.g^-1 to 75.31μg·.g^-1 at 15-30 cm soil depth between the same seasonal periods. Bacteria populations and MB-N showed similar increasing trends. Correlations between MB-C, MB-N, microbe populations, and rainfall were positive and linear. Significantly higher microbial activities took place in the plantations during the rainy season, increased with soil wetness, and decreased at greater soil depth.

关键词： Gmelina arborea plantation development seasonal variation microbe population microbial biomass sustainability Nigeria

Deep Reinforcement Learning-Based Resource Allocation for UAV-Enabled Federated Edge Learning

在线全文

学校读者我要写书评

暂无评论

Journal of Communications and Information Networks 2023年第1期8卷 1-12页

作者： Tianze Liu Tiankui Zhang jonathan Loo Yapeng Wang School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China School of Computing and Engineering University of West LondonLondon W55RFUK Faculty of Applied Sciences Macao Polytechnic UniversityMacao 999078China

The resource allocation of the federated learning(FL)for unmanned aerial vehicle(UAV)swarm systems are *** UAV swarms based on FL realize the artificial intelligence(AI)applications by means of distributed training on the basis of ensuring the security of private ***,the direct application of the FL in UAV swarms will incur high ***,in this article,we consider the resource allocation problem in FL for UAV *** avoid the high communication overhead between UAVs and the central server,we proposed an FL framework for UAV swarms based on mobile edge computing(MEC)in which model aggregation is migrated to edge *** the proposed framework,the total cost of the FL is defined as the weighted sum of the total delay of UAV swarms to complete the FL and system energy *** order to minimize the total cost of FL,we propose a resource allocation algorithm for joint optimization of computing resources and multi-UAV association based on deep reinforcement learning(DRL).The simulation result shows that:(1)compared with the benchmark algorithm,the proposed algorithm can effectively reduce the total cost of FL;(2)the proposed algorithm can realize the trade-off between task completion delay and system energy consumption through weight changes.

关键词： DRL FL MEC UAV

Investigation of a ship resonance through numerical simulation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2020年第5期32卷 969-983页

作者： S.S.Kianejad Hossein Enshaei jonathan Duffy Nazanin Ansarifard Australian Maritime College University of TasmaniaLauncestonAustralia

Understanding dynamic stability of a ship on a resonance frequency is important because comparatively smaller external forces and moments generate larger *** roll motion is most susceptible because of smaller restoring *** studies related to the failure modes such as parametric roll and dead ship condition,identified by second generation of intact stability criteria(SGISC)are performed at a resonance ***,the nature of resonance,where the model experiences an incremental roll motion,has not been well *** this study,nonlinear unsteady computational fluid dynamics(CFD)simulations were conducted to investigate the resonance phenomenon using a containership under a sinusoidal roll exciting *** capture the complexity of the phenomenon,simulations were conducted over a range of frequencies to cover the resonance frequency including lower and higher *** addition to the resonance frequency,the phase shift between roll exciting moment and roll angle,as well as the phase difference between acceleration and roll angle,were found to have significant effects on the occurrence of resonance.

关键词： Resonance harmonic excited roll motion natural frequency phase shift phase difference