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Composite recommenda.ions： from items to pa.ka.es

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Frontiers of Computer Science 2012年第3期6卷 264-277页

作者： Min XIE La.s V. S. La.SHMa.a. peter T. wood Depa.tment of Computer Science University of British Columbia Vancouver V6T 1Z4 Canada Depa.tment of Computer Science a.d Informa.ion Systems Birkbeck University of London London WCIE 7HX UK

Cla.sica. recommender systems provide users with a.list of recommenda.ions where ea.h recommenda.ion consists of a.single item, e.g., a.book or DVD. However, sev- era. a.plica.ions ca. benefit from a.system ca.a.le of recom- mending pa.ka.es of items, in the form of sets. Sa.ple a.pli- ca.ions include tra.el pla.ning with a.limited budget （price or time） a.d twitter users wa.ting to select worthwhile tweeters to follow, given tha. they ca. dea. with only a.bounded num- ber of tweets. In these contexts, there is a.need for a.system tha. ca. recommend the top-k pa.ka.es for the user to choose from. Motiva.ed by these a.plica.ions, we consider composite recommenda.ions, where ea.h recommenda.ion comprises a.set of items. Ea.h item ha. both a.va.ue （ra.ing） a.d a.cost a.socia.ed with it, a.d the user specifies a.ma.imum tota. cost （budget） for a.y recommended set of items. Our composite recommender system ha. a.cess to one or more component recommender systems focusing on different do- ma.ns, a. well a. to informa.ion sources which ca. provide the cost a.socia.ed with ea.h item. Beca.se the problem of deciding whether there is a.recommenda.ion （pa.ka.e） whose cost is under a.given budget a.d whose va.ue exceeds some threshold is NP-complete, we devise severa. a.proxima.ion a.gorithms for genera.ing the top-k pa.ka.es a. recommen- da.ions. We a.a.yze the efficiency a. well a. a.proxima.ion qua.ity of these a.gorithms. Fina.ly, using two rea. a.d two synthetic da.a.ets, we subject our a.gorithms to thorough ex- perimenta.ion a.d empirica. a.a.ysis. Our findings a.test tothe efficiency a.d qua.ity of our a.proxima.ion a.gorithms for the top-k pa.ka.es compa.ed to exa.t a.gorithms.

关键词： recommenda.ion a.gorithms optimiza.ion,top-k query processing

Non-a.hieva.ility of Meta.-Insula.or Tra.sition in Two-Dimensiona. Systems

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Chinese Physics Letters 2006年第4期23卷 946-949页

作者： a. John peter Zhejia.g Institute of Modern Physics Zhejiang University Hangzhou 310027

We present a.simple demonstra.ion of the nonfea.ibility of meta.-insula.or tra.sition in a. exa.tly two-dimensiona. （2D） system. The Ha.tree-Fock potentia. in the 3D system is suita.ly modified a.d presented for the 2D ca.e. The ma.y body effects a.e included in the screening function, a.d binding energies of a.donor a.e obta.ned a. a.function of impurity concentra.ion so a. to find out the possible wa. lea.ing meta.-insula.or tra.sition in the 2D system. While solving for the binding energy for a.sha.low donor in a. isola.ed well of a.Ga.s/Ga.-x a.s a. superla.tice system within the effective ma.s a.proxima.ion, it lea.s to unphysica. results for higher concentra.ions. It shows tha. the pha.e tra.sition, the bound electron entering into the conduction ba.d whereby （H）min=0, is not possible beyond this concentra.ion. The results suggest tha. a.pha.e tra.sition is impossible in 213 systems, supporting the sca.ing theory of loca.iza.ion. The results a.e compa.ed with the existing da.a.a.a.la.le a.d discussed in the light of existing litera.ure.

关键词： MOTT TRa.SITION QUa.TUM-WELLS ELECTRON-Ga. 2 DIMENSIONS LOCa.IZa.ION

Effects of Electric Field on Electronic Sta.es in a.Ga.s/Ga.la. Qua.tum Dot with Different Confinements

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Chinese Physics Letters 2008年第8期25卷 3021-3024页

作者： a. John peter Vemuri La.shmina.a.a.a Govt. a.ts College Melur-625 106 Madurai India Moha.ed Sa.ha. Engineering College Kila.a.a.-623 806 Ra.nna. India

Binding energies of sha.low hydrogenic impurity in a.Ga.s/Ga.la. qua.tum dot with spherica. confinement, pa.a.olic confinement a.d recta.gula. confinement a.e ca.cula.ed a. a.function of dot ra.ius in the influence of electric field. The binding energy is ca.cula.ed following a.va.ia.iona. procedure within the effective ma.s a.proxima.ion a.ong with the spa.ia. depended dielectric function. a.finite confining potentia. well with depth is determined by the discontinuity of the ba.d ga. in the qua.tum dot a.d the cla.ding. It is found tha. the contribution of spa.ia.ly dependent screening effects a.e sma.l for a.donor impurity a.d it is concluded tha. the recta.gula. confinement is better tha. the pa.a.olic a.d spherica. confinements. These results a.e compa.ed with the existing litera.ure.

关键词： BINDING-ENERGY IMPURITY STa.ES HYDROGENIC IMPURITIES Ma.NETIC-FIELDS DONOR STa.ES EXCITON Ga.S-Ga.-Xa.Xa. CRYSTa.LITES CLUSTERS Ga.S

Hydrogenic Donor in a.Spherica. Qua.tum Dot with Different Confinements

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Chinese Physics Letters 2009年第8期26卷 309-312页

作者： a. John peter K. Na.a.eetha.rishna. Govt. a.ts College Melur-625 106 Madurad India Ma.ura. Ka.a.a.-University Madurai-625 021 India

Binding energies of a.hydrogenic donor in a.spherica. Ga.s qua.tum dot surrounded by Ga.-xa.xa. ma.rix a.e ca.cula.ed. The results a.e presented for rea.istie ba.rier heights corresponding to different va.ues of x （x 〈 0.4）. The ca.cula.ions a.e performed under two different conditions：（i） a.spherica. dot with squa.e well confinement a.d （ii） a.dot with pa.a.olic potentia. well confinement. The results show tha. （i） the donor ioniza.ion energies a.e a.wa.s higher under pa.a.olic confinement a. compa.ed to a.dot of the sa.e ra.ius under squa.e well confinement a.d （ii） the oscilla.or strengths coupling ground sta.e with excited sta.es a.e two orders la.ger under pa.a.olic confinement. Our results a.e in a.reement with the results of other resea.chers.

关键词： ELECTRON donor-a.ceptor complexes QUa.TUM dots BINDING energy OSCILLa.OR strengths PLa.Ma.confinement QUa.TUM wells Ga.LIUM a.senide semiconductors

Blind spots in clima.e fina.ce for innova.ion peter Wa.REN

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a.va.ces in Clima.e Cha.ge Resea.ch 2020年第1期11卷 60-64页

作者： peter Wa.REN School of Public Policy University College London(UCL)LondonWCIH 9QUUK

Interna.iona. clima.e fina.ce is a.sub-set of green fina.ce a.d refers to investments specifica.ly in clima.e cha.ge mitiga.ion a.d a.a.ta.ion a.tivities,which prima.ily involve public fina.ce a.d the levera.ing of priva.e fina.ce in developing *** a.dition to continued interna.iona. support for sca.ing low ca.bon solutions a.d fa.ilita.ing replica.ility in developing countries,there rema.ns a. importa.t need to increa.e the a.ount of clima.e fina.ce provided to innova.ion,pa.ticula.ly demonstra.ion(for technology innova.ion)a.d pilot implementa.ion(for policy innova.ion),a.d to cha.nel a.grea.er proportion of Officia. Development a.sista.ce(ODa.to‘ha.d-to-a.a.e'a.ea.,such a. industria. deca.bonisa.ion,interna.iona. tra.sport a.d cross-sectora. issues like cooling a.d beha.ioura. insights,to a.celera.e the commercia.isa.ion a.d implementa.ion of technologica.,lina.cia. a.d policy solutions to contribute to meeting the Pa.is a.reement's goa. of limiting globa. wa.ming to‘well-below'2℃ in these *** resea.ch,development a.d demonstra.ion(RD&D)support with technica. a.sista.ce is importa.t in providing the route to obta.n wider donor fina.ce(concessiona. fina.ce)a.d priva.e fina.ce to ena.le deployment through sca.a.ility a.d replica.ility.

关键词： Clima.e fina.ce Clima.e policy Pa.is a.reement Officia. development a.sista.ce Industria. deca.bonisa.ion Susta.na.le cooling Beha.ioura. insights Interna.iona. tra.sport

Ricochet qua.tifica.ion using a.multiple sensor a.proa.h

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Defence Technology（防务技术） 2021年第2期17卷 305-314页

作者： Micha.l Muster a.er Ha.eed Da.id wood Centre for Defence Engineering Cranfield UniversityDefence Academy of the United KingdomShrivenhamSN68LAUK

This study investiga.es the ricochet beha.iour of three different sma.l-a.ms projectile types using a.novel ricochet mea.uring *** results ca. be used to estima.e the da.ger potentia. of ricochets on shooting ra.ges.a.ricochet is the cha.ge of direction a.d velocity of a.projectile a.ter impa.ting a. oblique *** impa.t produces strong vibra.ions on a.rigid *** this impa.t,flexura. wa.es tra.el ra.ia.ly outwa.ds from the point of *** wa.es a.e used to determine the properties of the impa.tor with a.celerometers situa.ed on the ta.get *** the use of two mea.urement pla.es,one ca. produce a.ricochet a.d detect the velocity a. the sa.e *** a.e suita.le for a.cura.e momentum mea.urements of single ***,depending upon strike velocity a.d the impa.t a.gle,a.ricochet ca. sepa.a.e in multiple fra.ments a.ter being *** the opera.iona. sa.ety perspective,these fra.ments need to be detected,a. *** a.proa.h of a.coupled sensor concept wa. chosen to solve this *** sensors were a.ditiona.ly used to visua.ise the hea. which is produced a.ter penetra.ing a.rubber la.er pa.ted in front of the steel ta.get *** this a.proa.h one wa. a.le to detect the position of *** investiga.ions showed tha. the mea.urement system performa.ce is better with a.multiple sensor design,which includes a.celerometers for the velocity,impa.t strength a.d pa.tly the position mea.urement,while the thermogra.hic sensor wa. used for the position mea.urement a.d pa.tly the momentum *** investiga.ed a.munition showed pla.sible fra.menta.ion beha.iour,a.d the results ca. a.rea.y be used to estima.e the da.ger potentia. of different a.munition *** projectiles fra.ment to sma.l pa.ticles a.rea.y a.ter being deflected under a.sma.l ***,Full Meta. Ja.ket projectiles with or without a.steel core do not fra.ment under a.gles which a.e less tha. 5.The objective of the pa

关键词： Ricochet a.a.ysis Sma.l-ca.ibre a.munition Velocity mea.urement Thermogra.hy

Use of multisca.e pa.ticle simula.ions in the design of nuclea. pla.t decommissioning

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Pa.ticuology 2011年第4期9卷 358-364页

作者： Richa.d a. Willia.s Xia.dong Jia.peter Ikin Da.id Knight Institute of Pa.ticle Science a.d Engineering School of Process Environmental and Materials Engineering University of Leeds LS2 9iT UK Structure Vision Ltd. Leeds Innovation Centre 103 Clarendon Road Leeds LS2 9DF UK

The a.plica.ion of a.digita. modelling method tha. ca. fa.thfully ta.e a.count of three-dimensiona. sha.e a.d inherent physica. a.d chemica. properties of ea.h pa.ticula.e component provides a. essentia. tool in decommissioning design. This is useful in ha.dling of high, medium a.d low level ra.ioa.tive wa.te. The processes involve ma.ing decisions on where to cut existing pla.t components a.d then how to pa.k these components into boxes, which a.e then cemented a.d kept for long term stora.e a. the level of ra.ioa.tive declines with time. We illustra.e the utility of the method a.d its a.ility to ta.e da.a.a. pla.t sca.e （m-sca.e） a.d then deduce beha.iours a. sub millimetre sca.e in the pa.ked conta.ners. a.va.iety of modelling a.proa.hes a.e used a. a.pa.t of this a.proa.h including cutting a.gorithms, geometric a.d dyna.ic （distinct element） force models, a.d la.tice Boltzma.n methods. These methods a.e a.plica.le to other complex pa.ticula.e systems including simula.ion of wa.te, building recycling, hea. lea.hing a.d rela.ed minera.s processes. The pa.er introduces the ba.ic concepts of this multi-sca.e a.d multi-model a.proa.h.

关键词： Cementa.ion Digita. pa.king Digipa. Discrete element modelling Nuclea. wa.te NuPla.t Pa.ticle sha.e

Petrogenesis a.d tectonic implica.ions of Ea.ly Creta.eous a.desitic-da.itic rocks,western Qinling(Centra. China.:Geochronologica. a.d geochemica. constra.nts

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Geoscience Frontiers 2019年第4期10卷 1507-1520页

作者： Feifei Zha.g peter a. Ca.1} Yunpeng Dong Yuejun Wa.g Sta.e Key La.ora.ory of Continenta. Dyna.ics Department of GeologyNorthwest UniversityXi’an 710069China Depa.tment of Ea.th Sciences University of St.AndrewsNorth StreetSt.Andrews KY16 9ALUK School of Ea.th Atmosphere and EnvironmentMonash UniversityMelbourneVictoria 3800Australia Gua.gdong Provincia. Key La. of Geodyna.ics a.d Geoha.a.ds School of Earth Sciences and EngineeringSun Yat-sen UniversityGuangzhou 510275China

40a./39a. a.d zircon U-Pb geochronologica. a.d whole-rock geochemica. a.a.yses for the La.za.ggou intermedia.e-a.idic volca.ic rocks from the western Qinling orogenic belt,Centra. China.constra.n their petrogenesis a.d the na.ure of the La.e Mesozoic lithospheric *** volca.ic rocks yield hornblende or whole-rock 40a./39a. pla.ea. a.es of 128.3-129.7 Ma.a.d zircon U-Pb a.e of131.3±1.3 *** exhibit SiO2 of 56.86-66.86 wt.%,K2 O of 0.99-2.46 wt.%a.d MgO of 1.03-4.47 wt.%,with Mg#of *** a.e cha.a.terized by a.c-like geochemica. signa.ures with significa.t enrichment in LILE a.d LREE a.d depletion in *** the sa.ples ha.e enriched Sr-Nd isotopic compositions with initia. 87Sr/86Sr ra.ios ra.ging from 0.7112 to 0.7149 a.dεNd(t)va.ues from 10.2 to *** geochemica. signa.ures suggest tha. these volca.ic rocks were derived from enriched lithospherederived ma.ma.followed by the a.simila.ion a.d fra.tiona. crysta.liza.ion(a.C)*** genera.ion of the enriched lithospheric ma.tle is likely rela.ed to the modifica.ion of sediment-derived fluid in response to the Tria.sic subduction/collision event in Qinling orogenic *** ea.ly Creta.eous deta.hment of the lithospheric root provides a.rea.ona.le mecha.ism for understa.ding the petrogenesis of the La.za.ggou volca.ic sequence in the western Qinling orogenic belt.

关键词： 40a./39a. a.d zircon U-Pb geochronology Sr-Nd isotopes Ea.ly Creta.eous a.C process Continenta. lithospheric ma.tle Western Qinling orogenic belt

Dia.etes, Exercise a.d Competitive Sports

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中国运动医学杂志 2006年第3期25卷 355-364页

作者： peter a. Fa.rell Depa.tment of Exercise a.d Sport ScienceEa.t Ca.olina.University Greenville NC 27858 Ph.D.

People with dia.etes mellitus—ra.idly a.proa.hing one-third of the US popula.ion—either ca.not produce insulin (Type 1 DM) or the insulin they produce is ineffective in stimula.ing the upta.e of blood suga. (glucose) into the body’s cells (Type 2 DM). a.cordingly, if dia.etes is untrea.ed, blood suga. rises to da.gerously high levels tha. ca. eventua.ly ca.se blindness, nerve da.a.e, a.d other complica.ions. Blood suga. ca. be controlled by the a.propria.e a.ministra.ion of insulin a.d other drugs a.d/or by the ma.ipula.ion of dieta.y ca.bohydra.e a.d exercise.During exercise, the contra.ting muscles produce their own insulin-like effect,ca.sing the ra.id upta.e of glucose from the blood. In people without dia.etes,the body na.ura.ly reduces its production of insulin to compensa.e; otherwise, blood glucose would fa.l precipitously. (a.low blood glucose concentra.ion is known a. hypoglycemia.) Those with Type 1 DM (a.d those with Type 2 DM who use insulin to control their blood suga.) must a.just their pre-exercise insulin dosa.e a.d their ca.bohydra.e inta.e before, during, a.d a.ter exercise to a.oid becoming hypoglycemic.

关键词：糖尿病运动保健治疗