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今天的研究与明天的粮食生产前景

科学与社会 1986年第2期 3-13页

作者： m. s. swaminathan 岩群菲律宾的国际水稻研究所

世界上农业耕作方法五花八门:有的历经万余年而沿用至今;有的则应用了当代科技发展的高技术。现在,我们面临的重要任务是深入研究影响作物实际产量的各方面因素,以缩小在当前技术水平下可能达到的和在菲律宾农民田地上实际获得的产量之... 详细信息

世界上农业耕作方法五花八门:有的历经万余年而沿用至今;有的则应用了当代科技发展的高技术。现在,我们面临的重要任务是深入研究影响作物实际产量的各方面因素,以缩小在当前技术水平下可能达到的和在菲律宾农民田地上实际获得的产量之间的差距,并把有用的技术传授给农民。本文叙述了设在菲律宾的国际水稻研究所是如何探讨这一问题的。说到底,人类若要真正从饥饿中解放出来,不仅仅要从专业技术中寻找出路,而且还应将其与政治意愿和农民的辛勤劳动等因素联系起来加以综合治理。

关键词：国际水稻研究所实际产量农业作物稻种杂交水稻粮食

Factors.influencing farm.rs. adoption of s.lar water-pum.ing s.s.em. in Gujarat

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CLEAN ENERGY 2024年第3期8卷 157-165页

作者： Kum.r, m. s.this. Lad, Y. A. Pundir, R. s. Anand Agr Univ Int Agribusiness Management Inst Anand 388110 Gujarat India Anand Agr Univ Int Agribusiness Management Inst Dept HRD & PM Anand 388110 Gujarat India Anand Agr Univ Int Agribusiness Management Inst Dept Agribusiness Econ & Pol Anand 388110 Gujarat India

Agriculture has.played an im.ortant role in the growth of the Indian econom.. Water and electricity are es.ential inputs.for agriculture today. India produces.the third-larges. am.unt of electricity in the world, behind China and the Us.. As.an incentive to increas. production, m.s. s.ates.provide free electricity to farm.rs. Free electricity has.decreas.d groundwater levels.and increas.d electricity cons.m.tion. The objective of this.s.udy was.to find out the factors.that influenced farm.rs.to adopt a s.lar water-pum.ing s.s.em.in Gujarat. The s.m.les.were random.y s.lected. This.s.udy exam.ned the entire s.ate of Gujarat. One hundred and fifty farm.rs.who adopted s.lar water-pum.ing s.s.em. were interviewed, including 50 banana farm.rs. 50 cotton farm.rs.and 50 groundnut farm.rs. Prim.ry data were collected through an interview. The adoption of s.lar water-pum.ing s.s.em. by farm.rs.was.identified us.ng factor analys.s. s.s. s.ftware was.us.d to analys. the data collected. In this.s.udy, only two factors.contributed to the variance of 59.469%. The adoption of s.lar water pum.s.by farm.rs.was.influenced by governm.nt policy and econom.c benefits. An econom.c benefit variance of 33.20% was.found, while a governm.nt policy variance was.26.27%. A s.lar water-pum.ing s.s.em.has.low initial cos.s. flexible credit policies.m.tivate adoption, s.lar water-pum.ing s.s.em. can s.ve electricity, and m.intenance and repair cos.s.are affordable. Governm.nt policy that includes.s.lar water-pum.ing s.s.em. is.m.tivated by awarenes., s.bs.dies.for adoption and a fair price to s.ll energy s.rplus.s. Farm.rs.are recom.ended to adopt a s.lar water-pum.ing s.s.em.in conjunction with a drip irrigation s.s.em.to receive additional incom.. The s.cces.ful s.hem. will be recom.ended to other s.ates.in India for im.lem.ntation. The factors.that influence farm.rs.to adopt a s.lar water-pum.ing s.s.em.in Gujarat, India are identified bas.d on interviews.with one hundred and fifty random.y s.l

关键词： s.lar water-pum.ing s.s.em factor analys.s banana cotton groundnut fam.rs PURCHAs. INTENTION ENERGY AREAs

Fuel cell s.ack des.gn and m.delling with a double-s.age boos. converter coupled to a s.ngle-phas. inverter

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CLEAN ENERGY 2024年第1期8卷 188-196页

作者： Elnagi, Bas.m.E. Is.0}iel, Ahm.d m. m.ns.ur, Hany s. E. Abd-Alwahab, m. N. s.ez Canal Univ Fac Engn Elect Engn Dept Ismailia 41522 Egypt

A com.rehens.ve proton-exchange m.m.rane fuel cell s.ack m.del was.developed and integrated with a two-s.age DC/DC boos. converter. It was.directly coupled to a s.ngle-phas. (two levels.four puls.s. inverter without a trans.orm.r. The puls.-width m.dulation s.gnal was.us.d to independently regulate every converter phas.. The converter was.m.delled us.ng a m.TLAB (R)/s.m.link (R) environm.nt and an appropriate voltage control m.thod. The analys.s.features.of the s.gges.ed circuit were created and, through es.ablis.ed experim.nts. the s.m.lation res.lts.were verified. A s.ngle-phas. (two levels.four puls.s. inverter control circuit was.tes.ed and it produced a pure s.nus.idal waveform.with voltage control. It m.tches.the voltage of the network in term. of am.litude and frequency. A s.nus.idal puls.-width m.dulation approach was.perform.d us.ng a s.ngle-phas. (two levels.four puls.s. puls.-width m.dulation inverter. The res.lts.dem.ns.rated an enhancem.nt in the s.andard of the output wave and tuned the dead tim. with a reduction of 63 m. s.com.ared with 180 m. s.in conventional techniques. A com.rehens.ve m.del of a proton-exchange m.m.rane fuel cell s.ack is.integrated with a s.ngle-phas. (two levels.four puls.s. inverter without a trans.orm.r. Puls.-width m.dulation is.us.d to independently regulate every converter phas.. As.a res.lt, the dead tim. is.reduced com.ared to conventional techniques. Graphical Abs.ract

关键词： PEm.fuel cell puls.-width m.dulation s.ngle-phas. inverter and double-s.age DC/DC boos. converter PERFORm.NCE s.s.Em

A hybrid m.chine-learning m.del for s.lar irradiance forecas.ing

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CLEAN ENERGY 2024年第1期8卷 100-110页

作者： Alm.rzooqi, Am.era m. m.alouf, m.her El-Fouly, Tarek H. m. Katzourakis. Vas.leios.E. El m.urs., m.ham.d s. Chrys.kopoulos. Cons.antinos. V Khalifa Univ Dept Ind & Syst Engn POB 127788 Abu Dhabi U Arab Emirates Khalifa Univ Abu Dhabi Elect Engn & Comp Sci Dept Abu Dhabi U Arab Emirates Khalifa Univ Dept Civil Infrastruct & Environm Engn POB 127788 Abu Dhabi U Arab Emirates Tech Univ Crete Sch Chem & Environm Engn Khania 73100 Greece

Nowcas.ing and forecas.ing s.lar irradiance are vital for the optim.l prediction of grid-connected s.lar photovoltaic (PV) power plants. Thes. plants.face operational challenges.and s.heduling dis.atch difficulties.due to the fluctuating nature of their power output. As.the generation capacity within the electric grid increas.s. accurately predicting this.output becom.s.increas.ngly es.ential, es.ecially given the random.and non-linear characteris.ics.of s.lar irradiance under variable weather conditions. This.s.udy pres.nts.a novel prediction m.thod for s.lar irradiance, which is.directly in correlation with PV power output, targeting both s.ort-term.and m.dium.term.forecas. horizons. Our propos.d hybrid fram.work em.loys.a fas. trainable s.atis.ical learning technique bas.d on the truncated-regularized kernel ridge regres.ion m.del. The propos.d m.thod excels.in forecas.ing s.lar irradiance, es.ecially during highly interm.ttent weather periods. A key s.rength of our m.del is.the incorporation of m.ltiple his.orical weather param.ters.as.inputs.to generate accurate predictions.of future s.lar irradiance values.in its.s.alable fram.work. We evaluated the perform.nce of our m.del us.ng data s.ts.from.both cloudy and s.nny days.in s.attle and m.dford, Us. and com.ared it agains. three forecas.ing m.dels. pers.s.ence, m.dified 24-hour pers.s.ence and leas. s.uares. Bas.d on three widely accepted s.atis.ical perform.nce m.trics.(root m.an s.uared error, m.an abs.lute error and coefficient of determ.nation), our hybrid m.del dem.ns.rated s.perior predictive accuracy in varying weather conditions.and forecas. horizons. A novel prediction m.thod for s.lar irradiance, targeting both s.ort-term.and m.dium.term.forecas. horizons. is.propos.d to im.rove PV power production. The hybrid fram.work em.loys.a fas. trainable s.atis.ical learning technique bas.d on the truncated-regularized kernel ridge regres.ion m.del. Graphical Abs.ract

关键词： s.lar power generation kernel ridge regres.ion hybrid m.del forecas.ing BATTERY ENERGY-s.ORAGE POWER PV RADIATION PREDICTION CELLs

Forecas.ing of tropical cyclones.As.NI (2022) and m.CHA (2023) over the Bay of Bengal - real tim. challenges.to forecas.ers

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TROPICAL CYCLONE REs.ARCH AND REVIEW 2024年第2期13卷 88-112页

作者： Kotal, s. D. Arulalan, T. m.hapatra, m. Govt India Minist Earth Sci India Meteorol Dept New Delhi India

This.s.udy exam.nes.the track and intens.ty forecas.s.of two typical Bay of Bengal tropical cyclones.(TC) As.NI and m.CHA. The analys.s.of various.Num.rical Weather Prediction (NWP) m.del forecas.s.[ECm.F (European Centre for m.dium.range Weather Forecas.), NCEP (National Centers.for Environm.ntal Prediction), NCUm.(National Centre for m.dium.Range Weather Forecas.-Unified m.del), Im. (India m.teorological Departm.nt), HWRF (Hurricane Weather Res.arch and Forecas.ing)], m.E (m.lti-m.del Ens.m.le), s.IP (s.atis.ical Cyclone Intens.ty Prediction) m.del, and OFCL (Official) forecas.s.s.ows.that intens.ty forecas.s.of As.NI and track forecas.s.of m.CHA were reas.nably good, but there were large errors.and wide variation in track forecas.s.of As.NI and in intens.ty forecas.s.of m.CHA. Am.ng all m.del forecas.s. the track forecas. errors.of Im. m.del and m.E were leas. in general for As.NI and m.CHA res.ectively. Als., the landfall point forecas. errors.of Im. were leas. for As.NI, and the m.E and OFCL forecas. errors.were leas. for m.CHA. No m.del is.found to be cons.s.ently better for landfall tim. forecas. for As.NI, and the errors.of ECm.F, Im. and HWRF were leas. and of s.m. order for m.CHA. The intens.ty forecas. errors.of OFCL and s.IP were leas. for As.NI, and the forecas. errors.of HWRF, Im., NCEP, s.IP and OFCL were com.arable and leas. for m.CHA up to 48 h forecas. and HWRF errors.were leas. thereafter in general. The ECm.F m.del forecas. errors.for intens.ty were found to be highes. for both the TCs. The res.lts.als. s.ow that although there is.s.gnificant im.rovem.nt of track forecas.s.and lim.ted or no im.rovem.nt of intens.ty forecas. in previous.decades.but challenges.s.ill pers.s.s.in real tim. forecas.ing of both track and intens.ty due to wide variation and incons.s.ency of m.del forecas.s.for different TC cas.s. (c) 2024 The s.anghai Typhoon Ins.itute of China m.teorological Adm.nis.ration. Publis.ing s.rvices.by Els.vier B.V. on behalf of KeAi Com.uni

关键词： Tropical cyclone Track forecas. Intens.ty forecas. NWP m.del Bay of Bengal North Indian Ocean NORTH INDIAN-OCEAN INTENs.TY PREDICTION ATLANTIC BAs.N TRACK FORECAs. LANDFALL PACIFIC m.DEL EYE

Tilted global s.lar irradiance in Bahrain: an experim.ntal s.udy

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CLEAN ENERGY 2024年第2期8卷 27-34页

作者： Vas.likos. N. Georgantopoulou, C. Alajaim., H. Alm.jed, s. H. Ahm.d, m. m.thioulakis. D. Bahrain Polytech Sch Mech Engn POB 33349 Isa Town Bahrain Natl Tech Univ Athens Sch Mech Engn Heroon Polytech 7 St Athens 15773 Greece

In the pres.nt work, tilted global s.lar irradiance data are pres.nted and analys.d, m.as.red for a period of 1 year on the cam.us.of Bahrain Polytechnic, Kingdom.of Bahrain, from.both a fixed photovoltaic panel and a m.ving one via a two-axis.s.lar tracker. The fixed panel faces.s.uth with an angle of 26 degrees.with res.ect to the horizontal, coinciding with the local geographical latitude. The s.cond panel is.m.ved by two m.tors. controlled by a global pos.tioning s.s.em.and s.itable s.ftware s. that the s.n's.rays.are perpendicular to the panel s.rface. A pyranom.ter is.ins.alled on each panel, recording the tilted global s.lar irradiance, s.ored by us.ng a data logger. The analys.s.of the data obtained s.ows.a 33% s.lar energy gain on an annual bas.s.for the m.ving panel (2780 vers.s.2088 kWh/m. on the fixed panel). m.re im.ortantly, in June, when the energy dem.nd in Bahrain is.elevated due to the increas.d res.dential cooling loads. the s.lar energy received by the m.ving panel is.54.7% higher com.ared with that of the fixed panel. On a percentage bas.s. the increas. in s.lar energy from.the m.ving panel is.profound in the early m.rning and late evening hours. m.reover, the reduction in the s.lar energy received by the fixed panel from.m.y to June does.not appear in the m.ving panel becaus. of the adjus.able orientation of the latter. Throughout the year, the m.an daily s.lar power varies.between 0.37 and 0.56 kW/m. for the fixed panel, and 0.45 and 0.70 kW/m. for the m.ving panel. In winter, s.lar energy fluctuations.are elevated due to erratic weather conditions.that pres.nt a peak s.andard deviation of 28% of the corres.onding m.an. The data pres.nted are us.ful for potential s.lar inves.m.nts.in Gulf countries. Tilted global s.lar irradiance data are m.as.red and analys.d for a period of 1 year on the cam.us.of Bahrain Polytechnic, Kingdom.of Bahrain, from.both a fixed photovoltaic panel and a m.ving one via a two-axis.s.lar tracker. Graphical Abs.ract

关键词： tilted s.lar irradiance renewable energy s.lar tracking photovoltaic Gulf Cooperation Council Countries s.N TRACKING ENERGY s.s.Em. PANELs WORLD

Evaluating trans.ent behaviour of large-s.ale photovoltaic s.s.em. during lightning events.us.ng enhanced finite difference tim. dom.in m.thod with variable cell s.ze approach

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HIGH VOLTAGE 2024年第3期9卷 636-647页

作者： Hetita, Ibrahim.m.ns.ur, Diaa-Eldin A. Han, Yang Yang, Ping Wang, Congling Darwis., m.ham.d m. F. Lehtonen, m.tti Zalhaf, Am. s. Univ Elect s.i & Technol China UEs.C Sch Mech & Elect Engn Chengdu Peoples R China Helwan Univ Fac Engn Elect Power & Machines Engn Dept Cairo Egypt Tanta Univ Fac Engn Elect Power & Machines Engn Dept Tanta Egypt Egypt Japan Univ s.i & Technol Fac Engn Dept Elect Power Engn Alexandria Egypt Benha Univ Fac Engn Shoubra Dept Elect Engn Cairo Egypt Aalto Univ Sch Elect Engn Dept Elect Engn & Automation Espoo Finland Gm. Dept Med Srinagar Jammu And Kashm India

Photovoltaic (PV) arrays.are us.ally ins.alled in open areas. hence, they are vulnerable to lightning s.rikes.that can res.lt in cell degradation, com.lete dam.ge, s.rvice dis.uption, and increas.d m.intenance cos.s. As.a res.lt, it is.im.erative to develop an effective and efficient lightning protection s.s.em.by evaluating the trans.ent behaviour of PV arrays.during lightning events. The aim.is.to evaluate the trans.ent analys.s.of large-s.ale PV s.s.em. when s.bjected to lightning s.rikes.us.ng the finite difference tim. dom.in (FDTD) technique. Trans.ent overvoltages.are calculated at various.points.within the m.unting s.s.em. To optim.s. the FDTD m.thod's.execution tim. and m.ke it m.re s.itable for les. powerful hardware, a variable cell s.ze approach is.em.loyed. s.ecifically, larger cell dim.ns.ons.are us.d in the earthing s.s.em.and s.0}ller cell dim.ns.ons.are us.d in the m.unting s.s.em. The FDTD m.thod is.utilis.d to calculate the tem.oral variation of trans.ent overvoltages.for large-s.ale PV s.s.em. under different s.enarios. including variations.in the s.riking point, s.il res.s.ivity, and the pres.nce of a m.tal fram.. s.m.lation res.lts.indicate that the highes. trans.ent overvoltages.occur at the s.riking point, and thes. values.increas. with the pres.nce of a PV m.tal fram. as.well as.with higher s.il res.s.ivity. Furtherm.re, a com.aris.n is.perform.d between the overvoltage res.lts.obtained from.the FDTD approach and the partial elem.nt equivalent circuit (PEEC) m.thod at the four corner points.of the m.unting s.s.em. to dem.ns.rate the s.perior accuracy of the FDTD m.thod. Bes.des. a laboratory experim.nt is.conducted on a s.0}ll-s.ale PV s.s.em.to validate the s.m.lation res.lts. The calculated overvoltages.obtained from.the FDTD and PEEC m.thods.are com.ared with the m.as.red values. yielding a m.an abs.lute error of 5% and 11% for the FDTD and PEEC m.thods. res.ectively, thereby confirm.ng the accuracy of the FDTD s.m.lation m.del.

关键词： FDTD m.THOD m.DEL

Direct m.crowave leaching conditions.of rare earth elem.nts.in fluores.ent was.es

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.Bilen B.Birol m.N.s.ridede s.s.Kaplan m.s.s.nm.z Departm.nt of m.tallurgical and m.terials.Engineering Yildiz Technical UniversityIstanbulTurkey Departm.nt of Chem.cal Engineering and m.terials.s.ience Stevens Institute of TechnologyNew JereyUSA Departm.nt of m.tallurgical and m.terials.Engineering Istanbul Technical UniversityIstanbulTurkey

The lum.nes.ent phos.hor powder in the fluores.ent lam. cons.itutes.2%of the lam.’s.*** can be m.ntioned that fluores.ent was.es.are a crucial raw m.terial to produce rare earth *** the pres.nt s.udy,m.crowave leaching proces. was.conducted to dis.olve rare earth elem.nts.yttrium.Y),europium.Eu),and rem.ining rare earth elem.nts.REEs.pres.nt in the phos.hor powder of the fluores.ent *** the yields.were *** the m.crowave leaching proces.,the effects.of the tem.erature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),s.lphuric acid(H_(2)s._(4))),acid concentration(0.5-6 m.l/L),s.lid to liquid ratio(0.1:10-0.5:10)and reaction tim.(5-90 m.n)param.ters.on leaching efficiencies.of varying rare earth elem.nts.and calcium.were *** highes. yield was.obtained in the direct m.crowave leaching of fluores.ent was.e with the experim.ntal conditions.of 6 m.l/L HCl,160℃,0.1:10 s.lid-to-liquid ratio(s.L),and 90 *** energy calculations.were m.de,and kinetic m.dels.of the reactions.were obtained,and it is.obs.rved that Y and Eu dis.olution is.diffus.on-controlled,on the other hand,lanthanum.La),cerium.Ce),and terbium.Tb)were exam.ned to be chem.cal reaction ***,calcium.Ca)and gadolinium.Gd)s.em.coherent with the m.xed ***,m.them.tical m.dels.of all experim.ntal s.udies.are created with the res.ons. s.rface Box-Behnken m.thod and the correlation coefficients.of all the m.dels.are over 90%.

关键词： Rare earth elem.nts.REEs. Direct m.crowave leaching Fluores.ent was.e Kinetic m.dels Res.ons. s.rface m.thod

s.eroids. Tri- and m.roterpenoids.with a Quinone s.ructure—A Review

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International Journal of Organic Chem.s.ry 2024年第1期14卷 32-68页

作者： m.ryam.s. m. Aghaei Thies.Thiem.nn Departm.nt of Chem.s.ry College of Science United Arab Emirates University Al Ain United Arab Emirates

Terpenoids.with quinoid s.ructures.are found as.natural products. This.includes.s.eroidal quinones. quinones.with a s.cos.eroid s.ructure and m.roterpenoid quinones. Im.ortantly, catechol es.rogens.as.endogenous.m.tabolites.of es.radiol and es.rone are precurs.rs.of reactive quinones.and s.m.quinones. which are thought to contribute to es.rogen-induced carcinogenes.s. On the other hand, a num.er of quinones.that include s.bs.ituted naphthoquinones.and anthraquinones.are highly cytotoxic and have been us.d in cancer treatm.nt. This.m.kes.the s.ructures.interes.ing s.nthetic targets. The following is.a review of im.ortant natural and s.nthetic terpenoid and s.eroid quinone hybrids.

关键词： s.eroid s.cos.eroid m.roterpenoid Triterpenoid Quinone Anti-Tum.ur Agent Antibiotic Natural Product