微分方程与数学建模

[]100828458(2000)0220006204(333000)[],,[];;;[]O175[]A,,,(,,),1,,,1:,1,xy=f(x)x,y=f(x)(),y=f(x)(y0)M(x,y)MT,:,112:2-1=2-21=213=1+2=22tg3=tg22=2tg21-tg2215220006JournalofJingdezhenCollegeVol.15No.2Jun.2000:2000-03-06:(1949-),,,tg2=dydx,tg3=yxyx=2dydx1-dydx2dydxdydx=-yx1+xy2032,024:0dydx=tg21,y=f(x)dydx=-yx+1+xy2,,xy=v,x=yv,dxdy=v+ydvdyv+ydvdy=1-v+1+v2dv1+v2=dyyx2+y2=-x+y2Cy2=C(C+2x),2?,,a,b,c2:2,x,y(3)P(x,y),Q(x+dx,y+dy),P,QdsPQ,T,PQ:T[tg(+d)-tg]=ads+bydx+cdxtg=dydx72:tg(+d)tg+dd(tg)d()3=tgddx(tg)dxdd=dydx+ddxdydxdxddxdydx=aTdsdx+bTy+CTds=dx2+dy2=dx1+dydx2dsdx=1+dydx2ddxdydx=aT1+dydx2+bTy+CTd2ydx2=aT1+dydx2+bTy+CT,,,,:,,,,d2ydx2=CT(9)(9)(),,x=0,dydx=0,y=C2Tx2+hh,,3,,?:4,,y,x,P(x,y)Q(x+dx,y+dy),P,QdsPQ,P,Q,TPQTtg(+d)-Ttg=wdsw,820004tg=dydxtg(+d)=dydx+ddxdydxdxds=dx1+dydx2d2ydx2=wT1+dydx25dydx=ddx=wT1+2d1+2=wTdx˜+1+2=wTx+C1,x=0,dydx=0,=0(),C1=0,˜+1+2=wTx+1+2=ewTx1+2-=1+1+2=e-wTx-,=12ewTx-e-wTxdydx=12ewTx-e-wTxy=T2wewTx+e-wTx+C26x=0,y=0,C2=-Twy=T2wewTx+e-wTx-Tw,,y=œ2exœ+e-xœ=œchxœ(14)92:,1993.10.ShallowTalkonBlurredMathematicsZhenChunling(MathsDept.,JingdezhenCollege,Jingdezhen,333000)Abstract:Blurredmathematicsisanew-developingbranchofmathematics,whichresearchesandhandlessomeblurredphenomenonofmathematicsandhasbeenwidelyappliedinmanyfields.Thisarticlegivesabriefaccoutofblurredmathematicsonfouraspectssoastomakeaprimaryimpressionuponthosewhowanttokeepabreastofthesubject.Keywords:blurset;subordinatedfuction;stochastic;obscure;jointnumber(9)[1],[M],;:1978.12DifferentialEquationandMathematicalModelWuDangui(ScientificResearchAgency,JingdezhenCollege,Jingdezhen,333000)Abstract:Byanalysingtheformingprocessofsearchlightreflector,archshapeofsuspensionbridgeandsuspended-chainline,thispaperworksouttheirmathematicalmodelsbymeansofdifferentialequa2tion.Keywords:differentialequation;parabola;suspended2chainline;mathematicalmodel412000