共查询到20条相似文献，搜索用时 250 毫秒
1.
Ⅰ.单词拼写。选出正确的字母或字母组合补全下列单词。使其完整与正确。1.__xc__seA.e,u B.i,u C.u,e D.a,u2.fr__ndA.ei B.ai C.ie D.ir3.r___tA.egh B.eir C.are D.igh4.w__lc__meA.o,e B.a,o C.e,o D.o,a5.m__tA.ei B.ee C.ie D.aeⅡ.选择填空1.It's a cat.____name is Mimi.A.He B.She C.It D.Its2.This is Wang Ming.I think____ 相似文献
2.
飞云 《小雪花(小学生成长指南)》2003,(10)
Fardownintheseathereisanotherbeautifulworld.Theseakingfamilyisthere.Hehassixprettydaughters,buttheyoungestdaughterbeautiful.Hereyesarelikebluesea.Herbodyisliketherose.Shehasthemostbeautifulvoice.But,liketheothermermaids,shehasnofeet.Insteadofthem,itisatailoffish.Thesixprincessesplayandlivehappilyallday.Andtheirgrandmotherlooksafterthembe－causetheyhavenomother.Theyoungestprincesslovestolistentothestoryofthepersonwholivesontheland.Theoldestprincessis15yearsold.Sheisoldenoughtogetachancetogo… 相似文献
3.
乐伟国 《小学生导刊(高年级)》2005,(4)
一、Magic Action小魔女和她的伙伴们来到少年宫(Children’s Palace)参观交通展览(exhibition)。各种展品新颖别致,款式各异,有实物的,有图片的,有模型的,漂亮极了!下面展示的就是部分展品的名称(name),请你把相对应的英汉词语找出来。1.bike a.小船2.bus b.飞机3.car c.坦克车4.fireengines d.马车5.jeep e.出租车6.m otorcycle f.洒水车7.policecar g.地铁8.racingcar h.轮船9.coach i.自行车10.subway j.卡车11.tank k.轿车12.truck l.赛车13.taxi m.公共汽车14.train n.警车15.wateringcar o.吉普车16.plane p.摩托车17.ship q.火车1… 相似文献
4.
近年来,很多单项填空题是针对学生的思维定势而设下的“陷阱”。学生遇到这种“陷阱”题时一定要弄清句子的意义和结构,并弄清题中的词语搭配。一定要学会辩证地、全面地分析问题,进而走出思维定势的“陷阱”,选出正确答案。1.Whodoyouconsideryourcomputer?A.tostealB.hadstolenC.stealingD.tohavestolen2.Tom,suretocometomorrow.A.isB.beC.wasD.wouldbe3.Whowouldyouratherwithyoutomorrow,TomorBob?A.havetogoB.havegoC.havegoneD.hadgo4.Ifyoudontgothere,I.A.neitherdoB.norwillC.sodoD.neitherdid5.Everyminuteismadefullu… 相似文献
5.
先做下面的题目,然后去掉划线部分,再做一次前后两次的答案一样吗?如果不一样,你知道其中的原因吗?1.Hehasthreesons,andoneofisanegineer.A.whichB.whomC.themD.who2.ThisistheveryroomIsleptinthevening.A.whereB.whichC.thatD.who3.Hesaidsomething,surprisedme.A.whichB.thatC.asD.when4.Isthisthefactoryyouvisitedlastweek?A.whichB.whereC.theoneD.when5.Thewomanhusbandwaswoundedthewarlivedaterriblelife.A.whoseB.whoC.whichD.whom6.Iamverysurprisedatallhesaidthemeeting.A.whichB.whatC.thatD.as7.hard,andyou'l… 相似文献
6.
七彩树1.Yestolife,notodrug.珍爱生命,拒绝毒品。2.Allforone,oneforall.人人为我,我为人人。3.Graspall,loseall.样样都要,全都失掉(贪多必失)。4.Lightcome,lightgo.来得容易,去得也快。5.Likefather,likeson.有其父必有其子。6.Loveme,lovemydog.爱屋及乌。7.Manymen,manyminds.十个人,十条心。8.Nopains,nogains.不劳而获。9.Oncebit,twiceshy.一朝被蛇咬,十年怕井绳。10.Onceateacher,alwaysateacher.一日为师,终身为父。11.Wellbegun,halfdone.良好的开端是成功的一半。12.Afallinthepit,againinyourwit.吃一堑,长一智。对仗工… 相似文献
7.
《初中生学习》2004,(11)
谁都知道1加1应该是2。然而在本题的英语游戏中会出现一种怪现象,即1加1还是1。你瞧,在图中每一个单词中,加上一合适的字母,就可以得到另一个单词,有趣吗?请来完成这个游戏,并按编号将新词填入句中。1.Whatalovely_____!2.Whatarethese?_____arepears.3.WegotoShanghaiby_____.4._____morning,MissWu.5.Areyouallinthe_____class?6.Idon’tlikebread.Ilike_____.7._____alot.8.Howoldareyou._____?9.Canyou_____LessonTwo?10.I’mverywell,_____you.11.Givemea_____ofmilk,please.12.Let’sgohome_____.13.Come_____,Tom!14.There’… 相似文献
8.
刘阳 《课堂内外(小学版)》2004,(1)
MyFriendIhaveagoodfriend.HisnameisLiuYang.JohnishisEnglishname.Heis10yearsold.Hehasbigeyes,asmallmouthandshorthair.Hestudieshard.Helikesplayingcomputergamesverymuch.Heisagoodstudent.Weoftenplaytogether.Heismygoodfriend.文/刘阳我有一个好朋友,他的名字叫刘阳 相似文献
9.
10.
《文教资料》2002,(10)
一、选择填空 ( ) 1Hle ca∞商ll】y,,,百ds,caJl you A.¨sten to,he￡ur fiom bovs andIne? B.He￡ur.1isten t0 C.Hear.hear D.Listen to.hear)2.Must I g0而t}l them toIn0ⅡI)w?N0,)rouA.ml王sm’fC.needn’t B.shouldn,t D can’t)3.Hmv r肌ch does tllis suitA.costC.takeB.sp朗dD.payHe wait untn the rain A.won’t,wiⅡstop B.won’t,st(Ip C.而U,st叩s D.耐U,’viⅡst叩)5.A:Hi,Ka‰B:Hi,Mary,Ihere.A.d叫’t knowC.山inkV叫Wer_e B.don't think D.didIl’t k110wten yea玛since t}1eyt0 F’瑚IIlce.A.was.m… 相似文献
11.
1 Introduction Direct methanol fuel cell ( DMFC) is desirable toserve as the power systemfor portable devices such ascellular phones , portable computers ,etc. due to thetheoretically high energy density and the liquid fuelused that can be stored and tran… 相似文献
12.
WU Xiao-juan ZHU Xin-jian CAO Guang-yi TU Heng-yong 《浙江大学学报(A卷英文版)》2007,8(9):1505-1509
The solid oxide fuel cell (SOFC) is a nonlinear system that is hard to model by conventional methods. So far,most existing models are based on conversion laws,which are too complicated to be applied to design a control system. To facilitate a valid control strategy design,this paper tries to avoid the internal complexities and presents a modelling study of SOFC per-formance by using a radial basis function (RBF) neural network based on a genetic algorithm (GA). During the process of mod-elling,the GA aims to optimize the parameters of RBF neural networks and the optimum values are regarded as the initial values of the RBF neural network parameters. The validity and accuracy of modelling are tested by simulations,whose results reveal that it is feasible to establish the model of SOFC stack by using RBF neural networks identification based on the GA. Furthermore,it is possible to design an online controller of a SOFC stack based on this GA-RBF neural network identification model. 相似文献
13.
To prevent the oxygen starvation and improve the system output performance, an adaptive inverse control (AIC) strategy is developed to regulate the air supply flow of a proton exchange membrane fuel cell (PEMFC) system in this paper.The PEMFC stack and the air supply system including a compressor and a supply manifold are modeled for the purpose of performance analysis and controller design. A recurrent fuzzy neural network (RFNN) is utilized to identify the inverse model of the controlled system and generates a suitable control input during the abrupt step change of external disturbances. Compared with the PI controller, numerical simulations are performed to validate the effectiveness and advantages of the proposed AIC strategy. 相似文献
14.
The operating temperature of a solid oxide fuel cell （SOFC） stack is a very important parameter to be controlled, which impacts the performance of the SOFC due to thermal cycling. In this paper, an adaptive fuzzy control method based on an affine nonlinear temperature model is developed to control the temperature of the SOFC within a specified range. Fuzzy logic systems are used to approximate nonlinear functions in the SOFC system and an adaptive technique is employed to construct the controller. Compared with the traditional fuzzy and proportion-integral-derivative （PID） control, the simulation results show that the designed adaptive fuzzy control method performed much better. So it is feasible to build an adaptive fuzzy controller for temperature control of the SOFC. 相似文献
15.
CHEN Yue-hua CAO Guang-yi ZHU Xin-jian 《浙江大学学报(A卷英文版)》2007,8(5):748-754
This paper describes a nonlinear model predictive controller for regulating a molten carbonate fuel cell (MCFC). In order to improve MCFC’s generating performance, prolong its life and guarantee safety, it must be controlled efficiently. First, the output voltage of an MCFC stack is identified by a least squares support vector machine (LS-SVM) method with radial basis function (RBF) kernel so as to implement nonlinear predictive control. And then, the optimal control sequences are obtained by applying genetic algorithm (GA). The model and controller have been realized in the MATLAB environment. Simulation results indicated that the proposed controller exhibits satisfying control effect. 相似文献
16.
This paper introduces the effects of cell operating temperature, methanol concentration and airflow rate, respectively, on the performance of direct methanol fuel cell （DMFC）. A novel method based on fuzzy neural networks identification technique is proposed to establish the performance model of DMFC. Three dynamic performance models of DMFC under the influences of cell operating temperature, methanol concentration, and airflow rate are identified and established separately. Simulation results show that modeling using fuzzy neural networks identification is satisfactory with high accuracy. It is applicable to DMFC control systems. 相似文献
17.
A maximum power point tracker for photovoltaic energy systems based on fuzzy neural networks 总被引：1，自引：0，他引：1
Chun-hua Li Xin-jian Zhu Guang-yi Cao Wan-qi Hu Sheng Sui Ming-ruo Hu 《浙江大学学报(A卷英文版)》2009,10(2):263-270
To extract the maximum power from a photovoltaic （PV） energy system, the real-time maximum power point （MPP） of the PV array must be tracked closely. The non-linear and time-variant characteristics of the PV array and the non-linear and non-minimum phase characteristics of a boost converter make it difficult to track the MPP for traditional control strategies. We propose a fuzzy neural network controller （FNNC）, which combines the reasoning capability of fuzzy logical systems and the learning capability of neural networks, to track the MPP. With a derived learning algorithm, the parameters of the FNNC are updated adaptively. A gradient estimator based on a radial basis function neural network is developed to provide the reference information to the FNNC. Simulation results show that the proposed control algorithm provides much better tracking performance compared with the filzzy logic control algorithm. 相似文献
18.
In order to improve the output efficiency of a photovoltaic (PV) energy system, the real-time maximum power point (MPP) of the PV array should be tracked closely. The non-linear and time-variant characteristics of the photovoltaic array and the non-linear and non-minimum phase characteristics of a boost converter make it difficult to track the MPP as in traditional control strategies. A neural fuzzy controller (NFC) in conjunction with the reasoning capability of fuzzy logical systems and the learning capability of neural networks is proposed to track the MPP in this paper. A gradient estimator based on a radial basis function neural network is developed to provide the reference information to the NFC. With a derived learning algorithm, the parameters of the NFC are updated adaptively. Experimental results show that, compared with the fuzzy logic control algorithm, the proposed control algorithm provides much better tracking performance. 相似文献
19.
主要研究基于比例压力阀的气动伺服系统的模糊神经网络（FNN）力同步控制问题。结合研究内容，设计和搭建了气动力控制实验台。针对常规模糊控制器在控制中没有学习功能、系统量化和分档误差较大、控制性能不够好等不足，设计了模糊神经网络控制器。它综合了神经网络具有的分布式存贮知识、学习记忆能力、容错性强等优点和模糊系统具有的直观知识表达方式、简捷迅速的逻辑推理和决策能力强等优点。具有优良的控制性能。 相似文献
20.
Jun Li Nan Gao Guang-yi Cao Heng-yong Tu Ming-ruo Hu Xin-jian Zhu Jian Li 《浙江大学学报(A卷英文版)》2010,11(1):61-70
In this paper, an application of a nonlinear predictive controller based on a self recurrent wavelet network （SRWN） model for a direct internal reforming solid oxide fuel cell （DIR-SOFC） is presented. As operating temperature and fuel utilization are two important parameters, the SOFC is identified using an SRWN with inlet fuel flow rate, inlet air flow rate and current as inputs, and temperature and fuel utilization as outputs. To improve the operating performance of the DIR-SOFC and guarantee proper operating conditions, the nonlinear predictive control is implemented using the off-line trained and on-line modified SRWN model, to manipulate the inlet flow rates to keep the temperature and the fuel utilization at desired levels. Simulation results show satisfactory predictive accuracy of the SRWN model, and demonstrate the excellence of the SRWN-based predictive controller for the DIR-SOFC. 相似文献