检索结果-南通市图书馆

CEs Transactions on Electrical Machines and systems 2024年第1期8卷 12-21页

作者： Prabhakaran Koothu Kesavan Umashankar subramaniam Dhafer j.Almakhles IEEE Renewable Energy Laboratory Department of Electrical EngineeringPrince Sultan UniversityRiyadh 12435Saudi Arabia

This paper,evaluate the effectiveness of a proposed speed loop pseudo derivative feedforward(PDFF)controller-based direct torque controller(DTC)for a PMsM drive against the performance of existing PI speed controller-based DTC and hysteresis current controller(HCC).The proposed PDFF-based speed regulator effectively reduces oscillation and overshoot associated with rotor angular speed,electromagnetic torque,and stator *** case studies,one using forward-to-reverse motoring operation and the other involving reverse-to-forward braking operation,has been validated to show the effectiveness of the proposed control *** proposed controller's superior performance is demonstrated through experimental verification utilizing an FPGA controller for a 1.5 kW PMsM drive laboratory prototype.

关键词： Direct torque control Pseudo derivative feedforward controller Permanent magnet synchronous motor(PMsM)

Dissociation cross sections ofψ(3770),ψ(4040),ψ(4160),andψ(4415)mesons with nucleons

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第4期76卷 93-112页

作者： Ruo-Qing Ding Xiao-Ming Xu H j Weber Department of Physics Shanghai UniversityBaoshanShanghai 200444China Department of Physics University of VirginiaCharlottesvilleVA 22904United States of America

We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a ■ meson leads to the dissociation of the ■ meson. We consider the reactions:■, and■, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and the ■ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the s-matrix *** cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-charmonium scattering quark interchange relativistic constituent quark potential model

Application of a simplified ADM1 for full-scale anaerobic co-digestion of cattle slurry and grass silage:assessment of input variability

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental science & Engineering 2024年第4期18卷 125-139页

作者： sofia Tisocco sören Weinrich Gary Lyons Michael Wills Xinmin Zhan Paul Crosson Civil Engineering College of Science and EngineeringUniversity of GalwayGalwayH91 TK33Ireland Teagasc Animal and Bioscience Research Department Animal and Grassland Research and Innovation CentreDunsanyC15 PW93Ireland Biochemical Conversion Department Deutsches Biomasseforschungszentrum gemeinnützige GmbHLeipzig 04347Germany Faculty of Energy·Building services·Environmental Engineering Münster University of Applied SciencesSteinfurt 48565Germany Agri-Food and Biosciences Institute HillsboroughBT266DRUK Ryan Institute University of GalwayGalwayH91 TK33Ireland MaREI Research Centre for Energy Climate and MarineRyan InstituteUniversity of GalwayGalwayH91 TK33Ireland

Mathematical modeling of anaerobic digestion is a powerful tool to predict gas yields and optimize the *** Anaerobic Digestion Model No.1(ADM1)is a widely implemented model for this ***,modeling full-scale biogas plants is challenging due to the extensive substrate and parameter characterization *** study describes the modification of the ADM1 through a simplification of individual process phases,characteristic components and required ***,the ability of the simplified model to simulate the co-digestion of grass silage and cattle slurry was evaluated using data from a full-scale biogas *** impacts of substrate composition(crude carbohydrate,protein and lipid concentration)and variability of carbohydrate degradability on simulation results were assessed to identify the most influential *** indicated that the simplified version was able to depict biogas and biomethane production with average model efficiencies,according to the Nash-sutcliffe efficiency(NsE)coefficient,of 0.70 and 0.67,respectively,and was comparable to the original ADM1(average model efficiencies of 0.71 and 0.63,respectively).The variability of crude carbohydrate,protein and lipid concentration did not significantly impact biogas and biomethane output for the data sets *** contrast,carbohydrate degradability seemed to explain much more of the variability in the biogas and methane ***,the application of simplified models provides a reliable basis for the process simulation and optimization of full-scale agricultural biogas plants.

关键词： ADM1 Agricultural feedstocks Biogas technology Input variability Parameter estimation

stand dynamics of old-growth hemlock forests in central Bhutan are shaped by natural disturbances

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Forest Ecosystems 2024年第4期11卷 434-447页

作者： Karma Tenzin Craig R.Nitschke Kathryn j.Allen Raphael Trouve Thiet V.Nguyen Patrick j.Baker school of Agriculture Foodand Ecosystem SciencesUniversity of Melbourne500 Yarra BlvdRichmondVictoriaAustralia school of Geography Planningand Spatial SciencesUniversity of TasmaniaSandy BayTasmaniaAustralia Forest science Institute of south Vietnam 1 Pham Van Hai StreetTan Binh DistrictHo Chi Minh CityViet Nam

Understanding how past disturbances have influenced the development of forests is critical for deciphering their current structure and composition and forecasting future *** this study,dendrochronological methods were applied to uncover the disturbance history of old-growth hemlock-dominated forests in central *** of tree-ring samples from two old-growth hemlock stands,located in two different topographic settings,identified the importance of gap-phase dynamics in facilitating recruitment and growth releases and producing complex,multi-aged structure s over *** site showed evidence of a near stand-replacing disturbance in the late 1700s,while the other showed no evide nce of high-severity disturbance at any time over the last 400 *** both sites low-to medium-severity disturbances,some of which appear to be associated with cyclones originating in the Bay of Bengal,dominated the disturbance *** hemlock stands exhibited a significant positive association between cyclone occurrence and growth release events and between recruitment pulses and growth release *** 1800 to 1970 there was an increase in recruitment of angiosperm tree species at most sites and a corresponding decline in conifer *** the past 50 years there has been little new recruitment;this may be due to light limitation in the understory from shade-tolerant angiosperms and bamboo in the lower strata of these *** variations in disturbance dynamics and recruitment were observed across the study sites,suggesting that other factors,such as topography and climate,may be influencing long-term stand development *** study highlights the complex interplay between historical disturbance regimes and tree recruitment in shaping the age and size structures of old-growth hemlock forests in central *** also provides new insights into the dynamics of these forests that can be used to support effective forest conservation and management i

关键词： Forest structure Hemlock forest Himalaya Natural disturbance

On the analytical solution of transient friction in channel flows

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1447-1466页

作者： F.j.GARCíA-GARCíA P.FARINAs-ALVARINO Department of Naval&Industrial Engineering Polytechnic School of EngineeringUniversity of A CorunaCampus Industrial de FerrolFerrol 15403A CorunaSpain Integraciones Técnicas de seguridad S.A.Pol.Ind.Espiritu SantoC/Nobel15Cambre 15650A CorunaSpain

The transient friction in channel mean flows is the sum of two contributions,i.e.,the underlying laminar flow(ULF)and the purely turbulent component(PTC),and the contributions are analyzed separately by theoretical *** is found that,the transient friction may be higher or remarkably lower than that in equal-Reynolds number steady-state *** universal time constant for plane-parallel laminar flows is reported,and the role of the time constant in a turbulent mean flow is *** is shown that the time constant is related to the turbulence's frozen ***,a study of the logarithmic layer during the transient flow is accomplished,which shows that the logarithmic layer is destroyed.

关键词： transient friction transient flow unsteady channel flow

Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 MeV

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第2期48卷 91-103页

作者： F.A.Rasulova N.V.Aksenov s.I.Alekseev R.A.Aliev s.s.Belyshev I.Chuprakov N.Yu.Fursova A.s.Madumarov j.H.Khushvaktov A.A.Kuznetsov B.s.Yuldashev joint Institute for Nuclear Research DubnaRussia Institute of Nuclear Physics of the Academy of sciences of the Republic of Uzbekistan TashkentUzbekistan Faculty of Chemistry of Lomonosov Moscow state University MoscowRussia National Research Center"Kurchatov Institute" MoscowRussia skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow state University MoscowRussia Faculty of Physics of Lomonosov Moscow state University MoscowRussia Institute of Nuclear Physics AlmatyRepublic of Kazakhstan

In this study,experiments were performed at bremsstrahlung end-point energies of 10-23 MeV with the beam from the MT-25 microtron using theγ-activation *** experimental values of relative yields were compared with theoretical results obtained on the basis of TALYs with the standard parameters and the combined model of photonucleon *** isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 ***,taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

关键词： bremsstrahlung photon cross section isospin splitting giant dipole resonance

Europium recovery process by means of polymeric nanoparticles functionalized with acrylic acid,curcumin and fumaramide

在线全文

学校读者我要写书评

暂无评论

journal of Rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.Martínez-Montoya j.M.del Río A.de j.Morales-Ramirez M.Corea Escuela superior de Ingeniería Química e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.Lindavista Escuela superior de Ingenieria Química e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.Lindavista Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/n

Polymeric nanoparticles of poly(methyl methacrylate) were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR) and ultraviolet-visible(UV-Vis) *** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(sEM).The polymeric materials were used for recovery of [Eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85% of [Eu] at pH of *** images of sEM after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50% of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of6.

关键词： [Eu] recovery Chelating effect Extraction process stripping process Emulsion polymerization Rare earths

Awareness of the Termination of Pregnancy Act of the Laws of Zambia among Women of Reproductive Age at Kanyama First Level Hospital in Lusaka District Zambia

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Open journal of Obstetrics and Gynecology 2024年第8期14卷 1267-1287页

作者： j. K. Botha C. C. Ngoma P. s. Munkoka Lusaka District Health Office Matero First Level Hospital Lusaka Zambia Department of Midwifery Womens and Child Health School of Nursing Sciences University of Zambia Lusaka Zambia College of Nursing and Midwifery University of Lusaka Lusaka Zambia

Background: Termination of pregnancy (TOP) in Zambia is guided by the Termination of Pregnancy (TOP) Act of 1972 and as amended in 1994 of the laws of Zambia. However, despite provision of Comprehensive abortion care services with the liberal law, statistics at Kanyama First Level Hospital in relation to unsafe illegal abortions are alarming. This study sought to understand the Awareness on the TOP Act of the laws of Zambia among women of reproductive age 15 - 49 years at Kanyama First Level Hospital in Lusaka District. Purpose of the study: To assess awareness on the TOP Act among women of reproductive age at Kanyama First Level Hospital in Lusaka, Zambia. Methodology: A convergent parallel mixed method design was conducted using both survey and in-depth interviews among women of reproductive age at Kanyama First Level Hospital in Lusaka District. The study surveyed 370 randomly sampled women aged 15 to 49 years old while the in-depth interviews included eight women purposively sampled from the survey population. survey data was analyzed using descriptive and inferential statistics while qualitative data thematic analysis was used. Results: The study found that 37% of the participants were aware of the TOP Act while 63.8% viewed legalization of abortion for any reason as wrong. The study results also showed that widowed women were 8 times more likely to be aware of the TOP Act compared to single women (AOR: 8.262;95% CI: 1.105, 61.778). Women in business were significantly more likely to be aware of the TOP Act compared to those who reported having no occupation. (AOR: 2.61;95% CI: 1.246, 5.499). Limited access to information, the social stigma attached to abortion, health care providers’ attitudes, cultural norms, values and religious beliefs, restrictive legal requirements, and absence of a supportive network were some of the barriers affecting awareness and utilization of available safe abortion care services. Conclusions: The research findings concluded that a

关键词： Awareness Termination of Pregnancy Act Barriers Determinants Women

Are there sex-based disparities in cataract surgery?

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： Matthew D.Geiger Anne M.Lynch Alan G.Palestine Nathan C.Grove Karen L.Christopher Richard s.Davidson Michael j.Taravella Naresh Mandava jennifer L.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIM:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado school of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

维普期刊数据库评论

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 Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： s.Pérez-Rodríguez M.Gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.j.Lázaro D.sebastián Instituto de Carboquímica(CsIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CsIC) Marie Curie 228049 MadridSpain synchrotron sOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide