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Adjoints of elliptic cone operators

Adjoints of elliptic cone operators
Adjoints of elliptic cone operators

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2000]Primary 35J70;Secondary 47A05,58J05,58J32ADJOINTS OF ELLIPTIC CONE OPERATORS JUAN B.GIL AND GERARDO A.MENDOZA Abstract.We study the adjointness problem for the closed extensions of a general b -elliptic operator A ∈x ?νDi?m b (M ;E ),ν>0,initially de?ned as an unbounded operator A :C ∞c (M ;E )?x μL 2b (M ;E )→x μL 2b (M ;E ),μ∈R .The case where A is a symmetric semibounded operator is of particular interest,and we give a complete description of the domain of the Friedrichs extension of such an operator. 1.Introduction Let M 0be a smooth paracompact manifold,m a smooth positive measure on M 0.Suppose A :C ∞c (M 0)→C ∞c (M 0)is a scalar linear partial di?erential operator with smooth coe?cients.Among all possible domains D ?L 2(M 0,m )for A as an unbounded operator on L 2(M 0)there are two that stand out:D max (A )={u ∈L 2(M 0,m )|Au ∈L 2(M 0,m )}where Au is computed in the distributional sense,and D min (A )=completion of C ∞c (M 0)with respect to the norm u + Au ,which can be regarded as a subspace of L 2(M 0,m ).Both domains are dense in L 2(M 0,m ),since C ∞c (M 0)?D min (A )?D max (A ),and with each domain A is a closed operator.Clearly D min (A )is the smallest domain containing C ∞c (M 0)with respect to which A is closed,and D max (A )contains any domain on which the action of the operator coincides with the action of A in the distributional sense.Also clearly,A with domain D max (A )is an extension of A with domain D min (A ).If M 0is compact without boundary and A is elliptic then D max (A )=D min (A );the interesting situations occur when A is non-elliptic or M 0is noncompact.In this paper we shall analyze the latter problem,assuming that M 0is the interior of a smooth compact manifold M with boundary and that A ∈x ?νDi?m b (M ;E ),ν>0,is a b -elliptic ‘cone’operator acting on sections of a smooth vector bundle E →M ;here x :M →R is a smooth de?ning function for ?M ,positive in M 0.

The elements of Di?m b (M ;E )are the totally characteristic di?erential opera-tors introduced and analyzed systematically by Melrose [8].These are linear op-erators with smooth coe?cients which

near the boundary can be written in lo-cal coordinates (x,y 1,...,y n )as P = k +|α|≤m a kα(xD x )k D αy .Such an opera-tor is b -elliptic if it is elliptic in the interior in the usual sense and in addition k +|α|=m a kα(0,y )ξk ηαis invertible for (ξ,η)=0;this is expressed more concisely by saying that the principal symbol of P ,as an object on the compressed cotan-gent bundle (see Melrose,op.cit.),is an isomorphism.It follows from the de?nition of b -ellipiticity that the family of di?erential operators on ?M given locally by

?P 0(σ)= j +|α|≤m a α,j (0,y )σj D αy ,called the indicial operator or conormal symbol

2JUAN B.GIL AND GERARDO A.MENDOZA

of P,is elliptic of order m for anyσ∈C.For the general theory of these oper-ators and the associated pseudodi?erential calculus the reader is referred to the paper of Melrose cited above,his book[9],as well as Schulze[14,15].An oper-ator A∈x?νDi?m b(M;E)is b-elliptic if P=xνA is b-elliptic.By de?nition the conormal symbol of A is that of P.For more details see Section2.

The measure used to de?ne the L2spaces will be of the form xμm for some real μ,where m is a b-density,that is,x m is a smooth positive density.The spaces L2(M;E;xμm)are de?ned in the usual way with the aid of a smooth but otherwise arbitrary hermitian metric on E.These spaces are related among themselves by canonical isometries with which L2(M;E;xμm)=x?μ/2L2b(M,E),where L2b(M,E) is the space de?ned by the measure m itself.

This said,the general problem we are concerned with is the description of the ad-joints of the closed extensions of a general b-elliptic operator A∈x?νDi?m b(M;E) initially de?ned as an unbounded operator

(1.1)

A:C∞c(M;E)?xμL2b(M;E)→xμL2b(M;E).

The case where A is a symmetric semibounded operator is of particular interest,and we give,in Theorem8.12,a complete description of the domain of the Friedrichs extension of such an operator.

Di?erential operators in x?νDi?m b(M;E)arise in the study of manifolds with conical singularities.The study of such manifolds from the geometric point of view began with Cheeger[3],and by now there is an extensive literature on the subject. In the speci?c context of our work,probably the most relevant references,aside from those cited above,are the book by Lesch[7],and the papers by Br¨u ning and Seeley[1,2],and Mooers[11].See also Coriasco,Schrohe,and Seiler[13].

As already mentioned,the domains D min(A)and D max(A)need not be the same. The object determining the closed extensions of A is its conormal symbol?P0(σ): C∞(?M)→C∞(?M).Because of the b-ellipticity,this operator is invertible for allσ∈C except a discrete set spec b(A),the boundary spectrum of A(or P),a set which(again due to the b-ellipticity)intersects any strip a

From the point of view of closed extensions there is nothing more to understand than that they are in one to one correspondence with the subspaces of E(A)= D max(A)/D min(A).The problem of?nding the domain of the adjoint is more delicate,and forces us to pass to the Mellin transforms of representatives of elements of E.Our approach entails rewriting the pairing[u,v]A=(Au,v)?(u,A?v),de?ned for u∈D max(A)and v∈D max(A?),where A?is the formal adjoint of A,in terms of the Mellin transforms of u and v,and proving certain speci?c nondegeneracy properties of the pairing.It is generally true(and well known)that in a general abstract setting,[·,·]A induces a nonsingular pairing of E(A)and E(A?).In the

ADJOINTS OF ELLIPTIC CONE OPERATORS3 case at hand,there is an essentially well de?ned notion of an element u∈D max(A) with pole‘only’atσ0∈spec b(A)∩{?μ?ν

σ0?i(ν+2μ)is nonsingular(modulo the respective minimal domains).

Our analysis of the pairing begins in Section5with a careful description of the Mellin transforms of elements in D max(A).The main result in that section is Proposition5.9,a result along the lines of part of the work of Gohberg and Sigal[4]. In Section6we prove in a somewhat abstract setting that the pairing alluded to above for solutions with poles at conjugate points is nonsingular(Theorem6.4).In Section7we link the pairing[·,·]A with the pairing of Section6.The main results are Theorems7.11and7.17.The?rst of these gives a formula for the pairing which in particular shows that the pairing is null when the poles in question are not conjugate,and the second,which is based on the formula in Theorem7.11and Theorem6.4,shows that the pairing of elements associated to conjugate poles is nonsingular.The formulas are explicit enough that in simple cases it is easy to determine the domain of the adjoint of a given extension of A.

We undertake the study of the domain of the Friedrichs extension of b-elliptic semibounded operators in Section8.The main result there is Theorem8.12,which is a complete description of the domain of the Friedrichs extension.Loosely speak-ing,the domain consists of the sum of those elements u∈D max(A)with poles‘only’in?μ?ν

Any closed extension of a b-elliptic operator A∈x?νDi?m b(M;E)as an operator D?xμL2b(M;E)→xμL2b(M;E)has the space xμ+νH m b(M;E)in its domain.The space H m b(M;E)is the subspace of L2b(M;E)whose elements u are such that for any smooth vector?elds V1,...,V k,k≤m,on M tangent to the boundary,V1...V k u∈L2b(M;E).Other than this,the set of domains of the closed extensions of di?erent b-elliptic operators in x?νDi?m b(M;E)are generally not equal.In Section4we provide simple su?cient conditions for the domains of two such operators to be the same.Not unexpectedly,these conditions are on the equality of Taylor expansion at the boundary of the operators involved,up to an order depending onν.We prove in particular that under the appropriate condition the domains of the Friedrichs extensions of two di?erent symmetric semibounded operators are the same.This is used in Section8as an intermediate step to determine the domain of the Friedrichs extension of such an operator,and a re?nement of the condition is obtained as a consequence.

Operators of the kind we investigate arise naturally as geometric operators.In such applicationsμis determined by the actual situation.It is convenient for us, however,to work with the normalization

x?μ?ν/2Axμ+ν/2:C∞c(M;E)?x?ν/2L2b(M;E)→x?ν/2L2b(M;E). rather than(1.1).Since the mappings x s:xμL2b(M;E)→xμ+s L2b(M;E)are surjective isometries,this represents no loss.In particular,adjoints and symmetry properties of operators are preserved.Also to be noted is that these transformations represent translations on the Mellin transform side,so it is a simple exercise to

4JUAN B.GIL AND GERARDO A.MENDOZA

recast information presented in terms of Mellin transforms of the modi?ed operator as information on the original operator.

2.Geometric preliminaries

Throughout the paper M is a compact manifold with(nonempty)boundary with a?xed positive b-density m,that is,a smooth density m such that for some (hence any)de?ning function x,x m is a smooth positive density.We will also?x a hermitian vector bundle E→M.

Fix a collar neighborhood U Y for each boundary component Y of M,so we have a trivial?ber bundleπY:U Y→Y with?ber[0,1).We can then canonically identify the bundle of1-densities over U Y with| |[0,1)?| |Y(the tensor product of the pullback to[0,1)×Y of the respective density bundles).

Let m be a b-density on| |[0,1)?| |Y.Then there is a smooth de?ning function x:Y×[0,1)→R vanishing at Y×0,and a smooth density m Y on Y,such that

m=

dx

ξ?m Y with h smooth,

positive,h(0,y)=1.Let x=gξwhere g is determined modulo constant factor

by the requirement that dξx

ξ(dξmeans di?erential in the variableξ;this

makes sense since we are dealing with a product manifold).Thus g(ξ,y)should satisfy the equation

?g

ξ

g=0

Since h=1whenξ=0,the solutions g are smooth acrossξ=0.Pick the one which is1whenξ=0.

We?x the choice of x for each boundary component.When working near the boundary we will always assume that the de?ning function was chosen above,and that the coordinates,if at all necessary,are consistent with a choice of product structure as above.By?x we mean the vector?eld tangent to the?bers of U Y→Y such that?x x=1.

If E,F→M are(smooth)vector bundles and P∈Di?m b(M;E,F)is a b-elliptic di?erential operator,then E and F are isomorphic.This follows from the fact that the principal symbol of P is an isomorphismπ?E→π?F whereπ:b T?M\0→M is the projection,and the fact that the compressed cotangent bundle b T?M admits a global nonvanishing section(since it is isomorphic to T?M and M is a manifold with boundary).Thus when analyzing b-elliptic operators in Di?m b(M;E,F)we may assume F=E(for more on this see[6]).

The Hilbert space structure of the space of sections of E→M is the usual one, namely integration with respect to m of the pointwise inner product in E:

(u,v)L2

b (M;E)

= (u,v)E m if u,v∈L2b(M;E).

ADJOINTS OF ELLIPTIC CONE OPERATORS5 Fix a hermitian connection?on E.If P∈Di?m b(M;E),then near a boundary component one can write

P=

m

?=0P??(?xD x)?

where the P?are di?erential operators of order m??(de?ned on U Y)such that for any smooth functionφ(x)and section u of E over U Y,P?(φ(x)u)=φ(x)P?(u),in

other words,of order zero in?xD

x .P is said to have coe?cients independent of x

near Y if??

x P k(u)=P k(??

x

u)for any smooth section u of E supported in U Y.

By means of parallel transport along the?bers of U Y→Y one can show that if P∈Di?m b(M;E),then for any N there are operators P k,?P N∈Di?m b(M;E)such that

P=

N

k=0P k x k+?P N x N

where P k has coe?cients independent of x near Y.If P k has coe?cients independent of x near Y then so does its formal adjoint P?k.To see this recall that since the

connection is hermitian,?x(u,v)E=(??

x u,v)+(u,??

x

v)if u and v are supported

near Y,so if they vanish on Y then

(??

x u,v)L2

b

(M;E)

=?(u,??

x

v)L2

b

(M;E)

.

One derives the assertion easily from this.

Fixω∈C∞c(?1,1)real valued,nonnegative and such thatω=1in a neigh-borhood of0.The Mellin transform of a section of C∞c(?M;E)is de?ned to be the entire function?u:C→C∞(Y;E)such that for any v∈C∞(Y;E|Y)

(x?iσω(x)u,π?Y v)L2

b (M;E)

=

1

σ))?.

3.Closed extensions

Recall?rst the abstract situation(cf.[12]),where A:D max?H→H is a densely de?ned closed operator in a Hilbert space H.Thus D max is complete with the graph norm · A induced by the inner product(u,v)+(Au,Av),and if D?D max is a subspace,then A:D?H→H is a closed operator if and only if D

6JUAN B.GIL AND GERARDO A.MENDOZA

is closed with respect to · A.Fix D min?D max,suppose D min is dense in H and closed with respect to · A.Let

(3.1)

D={D?D max|D min?D and D is closed w.r.t. · A}

Thus D is in one to one correspondence with the set of closed operators A:D?H→H such that D min?D?D max.For our purposes the following restatement is more appropriate.

Proposition3.2.The set D is in one to one correspondence with the set of closed subspaces of the quotient

(3.3)

E=D max/D min

In our concrete case A∈x?νDi?m b(M;E),ν>0,is a b-elliptic cone operator, considered initially as a densely de?ned unbounded operator

(3.4)

A:C∞c(M;E)?x?ν/2L2b(M;E)→x?ν/2L2b(M;E).

We take D min(A)as the closure of(3.4)with respect to the graph norm,and

D max(A)={u∈x?ν/2L2b(M;E)|Au∈x?ν/2L2b(M;E)},

which is also the domain of the Hilbert space adjoint of

A?:D min(A?)?x?ν/2L2b(M;E)→x?ν/2L2b(M;E).

Thus D max is the largest subspace of x?ν/2L2b(M;E)on which A acts in the dis-tributional sense and produces an element of x?ν/2L2b(M;E);one can de?ne A on any subspace of D max by restriction.These de?nitions have nothing to do with ellipticity.The following almost tautological lemma is based on the continuity of A:xν/2H m b(M;E)→x?ν/2L2b(M;E)and the fact that C∞c(?M;E)is dense in xν/2H m b(M;E).

Lemma3.5.Suppose A∈x?ν/2L2b(M;E),let D?D max(A)be such that A:D?x?ν/2L2b(M;E)→x?ν/2L2b(M;E)is closed.If D contains xν/2H m b(M;E)then D contains D min(A).In particular,xν/2H m b(M;E)?D min(A).

Adding the b-ellipticity of A as a hypothesis provides the following precise char-acterization of D min(A):

Proposition3.6.If A∈x?ν/2L2b(M;E)is b-elliptic,then

1.D min(A)=D max(A)∩ ε>0xν/2?εH m b(M;E)

2.D min(A)=xν/2H m b(M;E)if and only if spec b(A)∩{?σ=?ν/2}=?.

The proof requires a number of ingredients,beginning with the following funda-mental result[10],[14]:

Theorem3.7.Let A∈x?νDi?m b(M;E)be b-elliptic.For every real s andγ,

(M;E)

A:xγH s b(M;E)→xγ?νH s?m

b

is Fredholm if and only if spec b(A)∩{?σ=?γ}=?.In this case,one can?nd a bounded pseudodi?erential parametrix

Q:xγ?νH s?m

(M;E)→xγH s b(M;E)

b

such that R=QA?1and?R=AQ?1are smoothing cone operators.

ADJOINTS OF ELLIPTIC CONE OPERATORS7

Note that if A is b-elliptic we always can?nd an operator Q such that

QA?1:xγH s b(M;E)→xγH∞b(M;E)and

AQ?1:xγ?νH s b(M;E)→xγ?νH∞b(M;E)

are bounded for every s∈R,even if the boundary spectrum intersects the line {?σ=?γ}.Also in this case ker A and ker A?are?nite dimensional spaces. Moreover,for every u∈xγH s b(M;E),

u xγH s

b ≤ (QA?1)u xγH s

b

+ QAu xγH s

b

,

which implies

u xγH s

b ≤C s,γ u xγH s b+ Au xγ?νH s?m b

(3.8)

for some constant C s,γ>0.

As noted above,there is a bounded operator Q:xγ?νH s?m

b →xγH s b such that

R=QA?1:xγH s?m

b

→xγH∞b is bounded.Hence for u∈xγH s b

u xγH s

b ≤ Ru xγH s

b

+ QAu xγH s

b

,

which implies the estimate(3.8).

Lemma3.9.There existsε>0such that

D max(A)?→x?ν/2+εH m b(M;E).

Proof.The inclusion follows from(3.8)and the fact that,if u∈D max(A)then?u has no poles on{?σ=ν/2}.Chooseε>0smaller than the distance between spec b(A)∩{?σ<ν/2}and the line{?σ=ν/2}.The continuity of the embedding is a consequence of the closed graph theorem since D max(A)and x?ν/2+εH m b are both continuously embedded in x?ν/2L2b.

Recall that x?ν/2+εH m b(M;E)is compactly embedded in x?ν/2L2b(M;E).Hence if A with domain D is closed,then

(D, · A)?→x?ν/2L2b(M;E)compactly.

(3.10)

That this embedding is compact is a fundamental di?erence between the situation at hand and b-elliptic totally characteristic operators and is due to the presence of the factor x?νin A.

Lemma3.11.Letγ∈[?ν/2,ν/2]be such that spec b(A)∩{?σ=?γ}=?.Then A with domain D max(A)∩xγH m b(M;E)is a closed operator on x?ν/2L2b(M;E). Proof.Let{u n}n∈N?D max(A)∩xγH m b with u n→u and Au n→f in x?ν/2L2b. Further,let Q be a parametrix of A as in Theorem3.7.In particular,

QA=1+R:xγH m b(M;E)→xγH m b(M;E)is Fredholm.

So,Au n→f implies(1+R)u n→Qf in xγH m b,and Qf=(1+R)?u for some ?u∈xγH m b.Now,since dim ker(1+R)<∞,there is a closed subspace H?x?ν/2L2b such that x?ν/2L2b(M;E)=H⊕ker(1+R).IfπH denotes the orthogonal projection onto H,thenπH u n→πH u in x?ν/2L2b and,as above,

(1+R)πH u n→(1+R)πH?u in xγH m b.

ThusπH u n→πH?u in xγH m b?→x?ν/2L2b which implies thatπH u=πH?u∈xγH m b.

8JUAN B.GIL AND GERARDO A.MENDOZA

On the other hand,(1?πH)u n→(1?πH)u∈ker(1+R)?xγH m b.Therefore, u∈xγH m b and Au=f.In other words,A with the given domain is closed.

Momentarily returning to the abstract situation of a densely de?ned closed op-erator A:D max?H→H,let D?min be the domain of its adjoint.Further,let D?max be the domain of the adjoint of A:D min?H→H,and denote this adjoint by A?.Then we have D?min?D?max.

Let D?and E?be the analogues of(3.1)and(3.3)for A?.De?ne

[·,·]A:D max×D?max→C

by

[u,v]A=(Au,v)?(u,A?v).

(3.12)

Then[u,v]A=0if either u∈D min or v∈D?min,and[·,·]A induces a nondegenerate pairing

[·,·]?A:E×E?→C.

Indeed,suppose u∈D max is such that[u,v]A=0for all v∈D?max.Then(Au,v)= (u,A?v)for all v∈D?max,which implies that u belongs to the domain of the adjoint of A?:D?max?H→H,that is,u∈D min.Thus the class of u in E is zero. Likewise,if v∈D?max and[u,v]A=0for all u∈D max then v∈D?min.

Given D∈D,let D⊥?D?max be the orthogonal of D with respect to[·,·]A. Proposition3.13.Let D∈D.The adjoint A?of A:D?H→H is precisely the operator A?restricted to D⊥.Consequently,A is selfadjoint if and only if D=D⊥. Proof.Let A?:D??H→H be the adjoint of A|D.We have(Au,v)=(u,A?v) for all u∈D,v∈D⊥.Thus D⊥?D?and A?v=A?v if v∈D⊥.On the other hand,since D??D?max(because D?D min),it makes sense to compute[u,v]A for u∈D and v∈D?.For such u,v we then have[u,v]A=0since A?v=A?v for every v∈D?.Thus D??D⊥which completes the proof that D?=D⊥.

Proof of Proposition3.6.To prove part1we will show inclusion in both directions. Ifε>0is such that spec b(A)∩{?σ=?ν/2+ε}=?,then

xν/2H m b(M;E)?D max∩xν/2?εH m b(M;E),

so from Lemmas3.5and3.11we deduce D min(A)?D max(A)∩xν/2?εH m b(M;E). Thus,

D min(A)?D max(A)∩ ε>0xν/2?εH m b(M;E).

To prove the reverse inclusion let u∈D max∩ ε>0xν/2?εH m b and set u n=x1/n u for n∈N.Then{u n}n∈N is a sequence in xν/2H m b and as n→∞

u n→u in xν/2?εH m b,and Au n→Au in x?ν/2?εL2b

for everyε>0.In particular,xεAu n→xεAu in x?ν/2L2b.Chooseεsu?ciently small such that D max(A?)?x?ν/2+εH m b(Lemma3.9).Then for v∈D max(A?) (Au n,v)=(xεAu n,x?εv)→(xεAu,x?εv)=(Au,v)as n→∞.

On the other hand,(u n,A?v)→(u,A?v)and(Au n,v)=(u n,A?v)since u n∈D min(A).Hence(Au,v)=(u,A?v)for all v∈D max(A?),that is,[u,v]A=0for all v∈D max(A?)which implies u∈D min(A)since D min(A)=D max(A?)⊥.

ADJOINTS OF ELLIPTIC CONE OPERATORS9 To prove part2,suppose?rst that spec b(A)∩{?σ=?ν/2}=?.Then Lemma3.11gives that A with domain D max(A)∩xν/2H m b(M;E)is closed.Since xν/2H m b(M;E)?D max(A),Lemma3.5implies D min(A)=xν/2H m b(M;E).On the other hand,if D min(A)=xν/2H m b(M;E),then A with domain xν/2H m b(M;E) is Fredholm,so by Theorem3.7spec b(A)∩{?σ=?ν/2}=?

We will now prove that D max/D min is?nite dimensional.This is a consequence of the following proposition,which is interesting on its own,see Lesch[7,Lemma 1.3.15,Prop.1.3.16].

Proposition3.14.If A∈x?νDi?m b(M;E)is b-elliptic,every closed extension

A:D?x?ν/2L2b(M;E)→x?ν/2L2b(M;E)

is a Fredholm operator.Moreover,dim D(A)/D min(A)is?nite,and

ind A|D=ind A|D

+dim D(A)/D min(A).

min

In particular,

E(A)=D max(A)/D min(A)is?nite dimensional.

Below we will give a proof di?erent from that of Lesch.That the dimension of D max(A)/D min(A)is?nite can also be proved by observing that if A=x?νP with P∈Di?m b(M;E)and Au∈x?ν/2L2b(M;E),then P u∈xν/2L2b(M;E),so the Mellin transform of P u is holomorphic in?σ>?ν/2,from which it follows that?u(σ)is meromorphic in?σ>?ν/2,and holomorphic in?σ>ν/2since u∈x?ν/2L2b(M;E)(see[5],also[10]).On the other hand,if u∈D min,then?u(σ) is holomorphic in?σ>?ν/2.This type of argument leads to

Corollary3.15.If A∈x?νDi?m b(M;E)is b-elliptic then

D min(A)=D max(A)if and only if spec b(A)∩{?σ∈(?ν/2,ν/2)}=?.

We will analyze E(A)more carefully in the next sections.This will entail some repetition of work done by Gohberg and Sigal[4].

Our proof of Proposition3.14requires the following classical result[16]:

Lemma3.16.Let X,Y and Z be Banach spaces such that X?→Y is compact. Further let T∈L(X,Z).Then the following conditions are equivalent:

1)dim ker T<∞and rg T is closed,

2)there exists C>0such that for every u∈X

u X≤C( u Y+ T u Z)(a-priori estimate).

Proof of https://www.doczj.com/doc/382009754.html,ing(3.10)and Lemma3.16with X=(D, · A)and Y=Z=x?ν/2L2b(M;E),we obtain dim ker A|D<∞and rg A|D closed.On the other hand,the adjoint A?of a cone operator A is just a closed extension of its b-elliptic formal adjoint A?,cf.Proposition3.13.Applying again Lemma3.16we get dim ker(A|D)?<∞.

To verify the index formula consider the inclusionι:D min→D which is clearly Fredholm(use the same argument but now with X=(D min, · A),Y= x?ν/2L2b(M;E)and Z=(D, · A)).Then indι=?dim D/D min,hence

=ind(A|D?ι)=ind A|D+indι=ind A|D?dim D/D min.

ind A|D

min

10JUAN B.GIL AND GERARDO A.MENDOZA

As a consequence of Propositions3.2and3.14,for any closed extension of

A:C∞c(?M;E)?x?ν/2L2b(M;E)→x?ν/2L2b(M;E)

with domain D(A)there is a?nite dimensional space E′?D max(A)such that

D(A)=D min(A)⊕E′(algebraic direct sum).

From Proposition3.14we also get the following two corollaries

Corollary3.17.Let A:D1→x?ν/2L2b(M;E)and A:D2→x?ν/2L2b(M;E)be

closed extensions of A such that D1?D2,ind A|D

1<0and ind A|D

2

>0.Then

there exists a domain D with D1?D?D2such that ind A|D=0.

The interest of this corollary lies in the fact that the vanishing of the index is necessary for the existence of the resolvent and of selfadjoint extensions. Corollary3.18.Let A:D1→x?ν/2L2b(M;E)and A:D2→x?ν/2L2b(M;E)be closed extensions of A.Then

ind A|D

2?ind A|D

1

=dim D2/D min?dim D1/D min.

In particular,if D1?D2then

ind A|D

2?ind A|D

1

=dim D2/D1.

This corollary implies the well-known relative index theorems for operators acting on the weighted Sobolev spaces xγH m b(M;E),cf.[10],[14].

4.Equality of domains

In this section we give su?cient conditions for the domains of di?erent operators to be equal.Of these results,only the one concerning Friedrichs extensions will be used later on.

An operator A∈x?νDi?m b(M;E)is said to vanish on?M to order k(k∈N)if for any u∈C∞(M;E),xνAu vanishes to order k on?M.Let

?s?=min{k∈N|s≤k}.

Proposition4.1.Let A0,A1∈x?νDi?m b(M;E)be b-elliptic.

1.If A0?A1vanishes on?M,then D min(A0)=D min(A1).

2.If A0?A1vanishes to order?≤ν?1on?M,?∈N,then

D max(A0)∩xν2???1H m b(M;E).

3.If A0?A1vanishes to order?ν?1?on?M,then D max(A0)=D max(A1).

4.If A0and A1are symmetric and bounded from below and A0?A1vanishes to

order?ν?1?on?M,then the domains of their Friedrichs extensions coincide, that is,D F(A0)=D F(A1).

Proof.First of all,observe that in all cases it is enough to prove only one inclusion; the equality of the sets follows then by exchanging the roles of A0and A1.

To prove part1,write

A1=A0+(A1?A0)=A0+x?νP x

with P∈Di?m b(M;E)and suppose u∈D min(A0).There is then a sequence {u n}n∈N?C∞c(?M;E)such that u n→u and A0u n→A0u,in x?ν/2L2b.Con-sequently,xu n→xu in xν/2H m b and x?νP xu n→x?νP xu in x?ν/2L2b.Thus A1u n→A0u+x?νP xu which implies D min(A0)?D min(A1).

ADJOINTS OF ELLIPTIC CONE OPERATORS11 Now,let?∈N,?≤ν?1,and let u∈D max(A0)∩xν/2???1H m b.This means u∈xν/2???1H m b and A0u∈x?ν/2L2b.To prove that u∈D max(A1)∩xν/2???1H m b we only need to show that A1u belongs to x?ν/2L2b.Let P∈Di?m b(M;E)be such that A1=A0+x?νP x?+1.Since u∈xν/2???1H m b then x?νP x?+1u∈x?ν/2L2b. Hence A1u∈x?ν/2L2b which proves the second statement.

To prove the third statement,let u∈D max(A0),?=?ν?1?,and P as above. Then u∈x?ν/2H m b and x?νP x?+1u∈x?ν/2L2b.Thus A1u∈x?ν/2L2b and D max(A0)?D max(A1).

To prove part4we?rst prove the rather useful and well known abstract char-acterization of the domain of the Friedrichs extension of a symmetric semibounded operator given in Lemma4.3below.Suppose A:D min?H→H is a densely de?ned closed operator which is symmetric and bounded from below.Let A?: D max?H→H be its adjoint and let A F:D F?H→H be the Friedrichs extension of A.De?ne

(u,v)A?=c(u,v)+(A?u,v)for u,v∈D max,

(4.2)

where c=1?c0and c0≤0is a lower bound of A.

Lemma4.3.u∈D max belongs to D F if and only if there exists a sequence{u n}n∈N in D min such that

(u?u n,u?u n)A?→0as n→∞.

Proof.Because of the fact that D min is dense in D F with respect to the norm · A?induced by(4.2),every u∈D F can be approximated as claimed.

Let now u∈D max and let{u n}n∈N?D min be such that(u?u n,u?u n)A?→0, so u n→u in H.Let K?H be the domain of the positive square root R of A F+cI. Recall that D F=D max∩K.Hence u∈D max belongs to D F if u∈K,and the identity

u n?u? A?= R(u n?u?)

implies that{Ru n}n∈N also converges in H.Thus u∈K since R is closed.

We now prove part4of Proposition4.1.Suppose that A0and A1satisfy the hypotheses there.Then by parts1and3,D min=D min(A0)=D min(A1)and D max=D max(A0)=D max(A1),and from the fact that A0+A1?2A0vanishes to order?ν?1?we also get that D min(A0+A1)=D min and D max(A0+A1)=D max. Since A0and A1are symmetric and bounded from below,so is A0+A1.We will show that these three operators share the same Friedrichs domain by showing that

D F(A0+A1)?D F(A0)∩D F(A1).

(4.4)

Suppose this has been shown.Since[u,v]A

0=[u,v]A

1

=1

12JUAN B.GIL AND GERARDO A.MENDOZA

But then also

(1?c i )(u ?u n ,u ?u n )x ?ν/2L 2b +(A i (u ?u n ),u ?u n )x ?ν/2L 2b

as n →∞,i =0,1,so u ∈D F (A 0)∩D F (A 1).

5.Spaces of Meromorphic Solutions

If K is a ?nite dimensional complex vector space,we let M σ

0(K )be the space of germs of K -valued meromorphic functions with pole at σ0and Hol σ

0(K )be the subspace of holomorphic germs.These are naturally modules over the ring Hol σ0(C ).Let R ⊥be another ?nite dimensional complex vector space.If P (σ):K →R ⊥is a linear map depending holomorphically on σin a neighborhood of σ0,then P de?nes a map M σ0(K )→M σ0(R ⊥),which we also denote by P .

Lemma 5.1.Suppose that P (σ)is de?ned near σ=σ0,is invertible for σ=σ0but P (σ0)=0.Then there are ψ1,...,ψd ∈M σ0(K )be such that βj (σ)=P (σ)(ψj (σ))is holomorphic and β1(σ0),...,βd (σ0)is a basis of R ⊥.For any such ψj ,if

u ∈M σ0(K )and P u ∈Hol σ0(R ⊥),then there are f j ∈Hol σ0(C )such that u = d

j =1f j ψj .

Proof.Let {b j }d j =1be a basis of R ⊥and de?ne ψj =P ?1(b j ).Then the ψj are meromorphic with pole at σ0,P ψj =βj =b j is holomorphic,and the βj (σ0)form a basis of R ⊥.

Let now ψ1,...,ψd ∈M σ0(K )be such that βj (σ)=P (σ)(ψj (σ))is holomorphic and β1(σ0),...,βd (σ0)is a basis of R ⊥.If f ∈Hol σ0(R ⊥)then f = j f j βj for some f j ∈Hol σ0(C ),because the βj (σ0)form a basis,and each βj (σ0)can be written as a linear combination (over Hol σ0(C ))of β1,...,βd .If P u =

f then P (u ? d

j =0f j ψj )=0,so u = d

j =0f j ψj for σ=σ0,which is the equality of

meromorphic functions.

The lemma asserts that P ?1(Hol σ0(R ⊥

))is ?nitely

generated as a submodule of M σ0(K )over Hol σ0(C ).We will be interested in ?E σ0=P ?1(Hol σ0(R ⊥))/Hol σ0(K )as a vector space over

C .The following fundamental lemma paves the way to

describing a basis of ?E σ0.

Lemma 5.2.Suppose that P (σ)is de?ned near σ=σ0,is invertible for σ=σ0but P (σ0)=0.There are ψ1,...,ψd ∈M σ0(K )such that each βj (σ)=P (σ)(ψj (σ))is holomorphic,β1(σ0),...,βd (σ0)form a basis of R ⊥,and if

ψj =μj ?1

?=01

ADJOINTS OF ELLIPTIC CONE OPERATORS 13

Order them so that {μj }d j =1is nonincreasing and let

?μ1=max {μj |j =1,...,d }

?μi =max {μj |μj

s i =max {j |μj =?μi },

(5.4)that is,

?μ1=μ1=···=μs 1>?μ2=μs 1+1=···=μs 2>···>?μL =μs L ?1+1=···=μd If the vectors ψj 0,j =1,...,s 1,are not linearly independent,then order the ψj with j ≤s 1so that ψ10,...,ψs ′1,0is a maximal set of linearly independent

vectors among {ψj 0|1≤j ≤s 1},write

ψk 0=s ′

1 j =1

a kj ψj 0for k =s ′1+1,...,s 1,

and replace ψk by ψk ?

s ′1j =1a kj ψj for k =s ′1+1,...,s 1.Now P (ψk )=βk ?

s ′

1j =1a kj βj for these indices,so it is still true that the P (ψj )(0)form a basis.With μj denoting the order of the pole of the new ψj ,and again assuming the orders form a nonincreasing sequence,let ?μi and s i be de?ned as above.Suppose that already ψj 0,j =1,...,s i is an independent set.If ψs i +1,0depends linearly on ψ1,0,...,ψs i ,0then put s ′i +1=s i .Otherwise,reorder ψs i +1,0,...,ψs i +1,0so that ψs i +1,0,...,ψs ′i +1,0together with ψj 0,j =1,...

,s i are a maximally independent

set in {ψj 0|1≤j ≤s i +1}.If s ′i +1

ψk 0=s ′i +1

j =1

αkj ψj 0,k =s ′i +1+1,...,s i +1.

Replacing ψk by ψk ? s ′

i +1j =1αkj σμj ??μi +1ψj (s ′i +1+1≤k ≤s i +1),reordering by

decreasing order of the pole (which reorders only ψj ,j >s ′

i +1),now have that the

leading coe?cients of the ψj ,j ≤s i +1,are independent.

Lemma 5.5.With the setup of Lemma 5.2,let ψ1,...,ψd ∈M σ

0(K )be as stated there,and let μj be the order of the pole of ψj .Let

?E σ0=P ?1

(Hol σ0(R ⊥))/Hol σ0(K ),

regarded as a vector space over C .Then the images in ?E σ0of the elements

(σ?σ0)?ψj ,j =1,...,d,?=0,...,μj ?1

form a basis of this space.

Proof.As before assume σ0=0.Because of Lemma 5.1the images of the σ?ψj span,and we only need to prove linear independence.Suppose d

j =1 μj

?1k =0u jk σk ψj is

holomorphic.Modulo holomorphic functions,

ψj =μj ?1

?=01

14JUAN B.GIL AND GERARDO A.MENDOZA (where theψj0are independent)so

u(σ)=

d

j=1μj?1 k=0μj?k ?=0u jk

σ?μ1???k

ψj?+

d

j=s1+1μj?1 k=0μj?k ?=0u jk

ADJOINTS OF ELLIPTIC CONE OPERATORS15

Note that K?μ

1?···?K?μ

L

=K,dim K?μ

?

=s?and m?μ

?

:K?μ

?

→K?μ

?

is

surjective.As in see Gohberg and Sigal[4],the numbersμj will be called the partial multiplicities of P(atσ0).

Lemma5.7.Let{ψ?i}d i=1,{ψj}d j=1?Mσ

(K)be as in Lemma5.2,both sequences ordered so that the sequences{μ?i},{μj}of the orders of the poles is nonicreasing. Thenμ?i=μi for all i and

ψ?i=

d j=1f ijψj

where the f ij are holomorphic,form a nonsingular matrix and f ij=(σ?σ0)μi?μj?f ij for some holomorphic?f ij ifμi>μj.Conversely,given holomorphic functions f ij forming a nonsingular matrix and with f ij/(σ?σ0)μi?μj holomorphic whenμi>μj, then theψ′j de?ned by the formula above satisfy the conclusion of Lemma5.2.

We leave the proof of this to the reader.It uses the previous lemma and its proof.

If K is a hermitian vector space,letφ1,...,φd be an orthonormal basis of K such that for each?=1,...,L,

φ1,...,φs

?∈K?μ

?

Then for j=s??1+1,...,s?we can pickψj∈K?μ

?such that m?μ

?

(ψj)=φj,that is,

if K is hermitian then theψj can be chosen to have orthogonal leading coe?cients. Proposition5.8.Let P(σ):K→R⊥be de?ned and holomorphic nearσ=σ0, invertible forσ=σ0but P(σ0)=0.Then

1.there areψ1,...,ψd∈Mσ

0(K)such that eachβj=Pψj∈Holσ

(R⊥),

β1(σ0),...,βd(σ0)form a basis of C d,and if

ψj=μj?1 ?=01

16JUAN B.GIL AND GERARDO A.MENDOZA

(Kμbeing de?ned usingσ0)and(σ?σ0)μjχ(σ)|σ=σ

=0.Soψj?χhas the same leading term asψj but now the coe?cient of(σ?σ0)?μj+?isψ0j?which is orthogonal toψk0for k such thatμk≥μj??.We may then replaceψj byψj?χ.The proof is completed by‘reverse’induction on n=μj??beginning with n=?μ1?1,the above being both the?rst and general steps.

Let now Y be a compact manifold and E a complex vector bundle over Y.We?x a hermitian metric on E and riemannian metric on E with respect to which we de?ne the Sobolev spaces H s(Y;E).Let P(σ):H m(Y;E)→L2(Y;E)be a holomorphic family of elliptic operators of order m de?ned forσnearσ0in C.Suppose P(σ)is invertible forσ=σ0but P(σ0)is not invertible.Let K=ker P(σ0),R=rg P(σ0). Then K and R⊥are?nite dimensional of the same dimension,say d,and consist of smooth sections of E.Regard P(σ)as an operator

P11(σ)P12(σ) P21(σ)P22(σ) :

K

K⊥

R⊥

R

in the usual way.All the P ij are holomorphic,and the operator P22(σ)is invertible

forσclose toσ0.Thus P11?P12P?1

22P21:K→R⊥depends holomorphically on

σ∈U and is invertible forσ=σ0.We can then?nd?ψ1,...,?ψd∈Mσ

(K)such that(P11?P12P?122P21)?ψj∈Holσ

(R⊥),as in Lemma5.2.Letψj be the singular

part of?ψj?P?1

22P21?ψj.In this last function,P?1

22

P21?ψj has values in K⊥,while

j

has values in K,so the order of the pole ofψj is the same as that of?ψj(there is

no cancellation).Note that furthermore the order of the pole of P?1

22

P21?ψj is lower than that of?ψj because P?122P21vanishes atσ=σ0.Letμj be the order of the pole ofψj.

Proposition5.9.Let?u be an H m(Y;E)-valued meromorphic function with pole at0.Then P(σ)(?u(σ))is holomorphic if and only if there are C-valued polynomials p j(σ)of degreeμj?1such that?u? d j=1p j(σ)ψj(σ)is holomorphic.Thus if?f is holomorphic and?u=P(σ)?1(?f),then?u is meromorphic with singularity of the form d j=1p j(σ)ψj(σ).

Proof.Suppose?f=f⊕g is a holomorphic function with values in R⊥⊕R and let ?u=u⊕v=P(σ)?1(f+g),σ=σ0,decomposed according to K⊕K⊥,so

P11u+P12v=f

P21u+P22v=g

From the second equation,v=P?1

22

(g?P21u),which replaced in the?rst gives

(P11?P12P?122P21)u=f?P12P?122g.

Since the?βj=(P11?P12P?122P21)?ψj are holomorphic nearσ0and independent at σ0,there are f j,q j∈Hol0(C)such that f= f j?βj,P12P?122g= q j?βj(the q j vanish atσ0because P12does).Then u= j(f j?q j)?ψj.Replacing this in the expression for v gives

v=P?1

22

g+ j(f j?q j)P?122P21?ψj

ADJOINTS OF ELLIPTIC CONE OPERATORS17

so

u+v= (f j?q j)(?ψj?P?122P21?ψj)+P?122g

= j p j(σ)ψj+h,

where the p j are polynomials and h is holomorphic.

Note that eachψj can be written as

ψj(σ,y)=μj?1

?=01

ζj?ζk μk,

let p j(ζ;ζ1,...,ζs)= k=j?jk.Then p j vanishes to orderμk atζk,k=j,and

18JUAN B.GIL AND GERARDO A.MENDOZA

has value 1at ζj ,so p j =1+(ζ?ζj )a j .The a j are polynomials in ζwhose coe?cients depend holomorphically on the ζj .Let b j = μj ?1?=0(?1)?[(ζ?ζj )a j ]?.This is again a polynomial in ζ,and so is q j =b j p j .Thus there are polynomials in ζwith coe?cients depending on the ζj ,h j,k (ζ;ζ1,...,ζs ),j,k =1,...,s ,such that

Q j (ζ;ζ1,...,ζs )=δjk +(ζ?ζk )μk h j,k (ζ;ζ1,...,ζs )

Let now q j (σ,τ)=Q j (τiσ;τiσ1,...,τiσs ),de?ned for those τfor which the numbers τiσj are distinct.Since this is a polynomial in τiσ,and since ?E is invariant under multiplication by τiσ,each q j de?nes a linear map πj :?E →?E .Since q j (σ,τ)=δjk +(σ?σ)μk ?h j,k (σ,τ),πj ψj ∈M ?,{σj }(H )/Hol ?(H )and πj ?πk =δjk πj ,and since s j =1q j =1, j πj =I .Thus with ?E

j =πj (?E )we get ?E

=?E 1⊕···⊕?E s The spaces ?E

j are invariant under multiplication by τiσbecause τiσq j =q j τiσ.The πj are independent of τ.Suppose now that ?E ?M ?,{σ0}(H )/Hol ?(H )is invariant under multiplication by τiσfor all τ(τ=e su?ces).Let λ(w )= N ?=1(?1)

?+1σ0(K )→M σ0(C )

by M σ0(K )×M

σ))∈M σ0(C ).and likewise a pairing ισ0,R ⊥associated with R ⊥.Let P (σ):K →R ⊥be de?ned and holomorphic in a neighborhood of σ0∈C .De?ne P ?(σ)=P (

σ0.Then with the induced map P ?:M σ0(K )we have

ισ0,R ⊥(P (σ)u (σ),v (σ))=ισ0,K (u (σ),P ?(σ)v (σ)).

Furthermore,de?ne Θ:M σ0(C )→M

f (

σ0(C )→M σ0(C ).

ADJOINTS OF ELLIPTIC CONE OPERATORS19

Lemma6.1.Letβ1,...,βd∈Holσ

(R⊥)be such that theβj(σ0)are independent. Then there are?β1,...,?βd∈Hol

σ0

(C).We need

ισ

0,R⊥

(βi,?βj)= ?Θ(h?j)(b i,b?)+(σ?σ0) k,?a ikΘ(h?j)(b k,b?)=δij, or,with the matrices H=[h?j],A=[a ik],B=[(b k,b?)],

BΘ(H)+(σ?σ0)ABΘ(H)=I

so set

Θ(H)=[I+(σ?σ0)B?1AB)]?1B?1.

Lemma6.2.Let P(σ):K→R⊥be de?ned and holomorphic nearσ0,invertible forσ=σ0,P(σ0)=0.Letψj∈Mσ

(K)have independent leading coe?cients

and be such thatβj=Pψj∈Holσ

0(R⊥),with theβj(σ0)linearly independent.Let

j

∈Hol

σ0

(K)be such that

ισ

0,K

(?β?i,β?j)=δij.

Then P??βj=(σ?

(σ?

σ0),thus the multiplicitiesμ?j for P?are the same as those for P,μ?j=μj.

Proof.We have P?β?j=(σ?σ0)μjβj,so

ισ

0,R⊥

(P?β?j,?βk)=(σ?σ0)μkδjk

=(σ?σ0)μkισ

0,K

(?β?j,β?k)

=ισ

0,K

(?β?j,(σ?

σ0)μkβ?k.

20JUAN B.GIL AND GERARDO A.MENDOZA

With the assumptions on P (σ)as in the previous lemma let

u ∈P ?1(Hol σ0(K ))and v ∈(P ?)?1(Hol

2π |σ?σ0|=εισ0,R ⊥

(P u,v )dσ.

The circle of integration is oriented counterclockwise.If v is holomorphic,then

[u,v ]P ,σ

0=0because P u is holomorphic.If u is holomorphic,then also [u,v ]P ,σ0=0,

since 1

2π |σ?σ0|=ε

ισ0,R ⊥(u,P ?v )dσ

Thus [·,·]P ,σ0de?nes a pairing

[·,·]?P ,σ0:?E σ0×?E ?

σ0=(P ?)?1(Hol σ0(R ⊥).

(6.3)

Theorem 6.4.[·,·]?P ,σ0is a nonsingular paring of vector spaces.

Proof.Pick ψj ∈M σ0(K )such that P ψj =βj ∈Hol σ0(R ⊥

),with the leading coe?cients

of the ψj forming a basis of K and with the βj (σ0)forming a basis of

R ⊥.Let ?βj ,?β?j ,and β?j be as in Lemma 6.2.According to the proof of Lemma 5.5,

if u ∈?E σ0and v ∈?

E ?σ0)?v j?ψ?j

(6.5)with constant u ik and v j?.Now,

P (u )=d i =1μi ?1

k =0

(σ?σ0)k u ik βi so

ισ0,R ⊥(P u,v

)=d i,j =1μi ?1 k,?=0

(σ?σ0)k +?u ik v j?ισ0,R ⊥(βi ,?βj )

=d j =1μj ?1

k,?=0

(σ?σ0)k +??μj u jk

v j?=i d j =1μj ?1

k =0u jk

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目录 一、预压目的 (1) 二、支架情况 (1) 三、荷载情况 (2) 四、预压方案 (4) 4.1 加载分级 (4) 4.2 卸载分级 (5) 4.3 测量及记录 (5) 4.4 加载材料及堆码 (6) 五、安全措施 (7)

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图2-1

图2-2 三、荷载情况 根据分析,支架预压需要计算0#块在墩顶3.2m范围以外的混凝土重量,单侧共205.6t,一个墩压重为411.2t。 四、预压方法 4.1、加载分级 根据现场条件,采用堆码砂袋的方法模拟支架的实际受力情况对其进行等效逐级预加载,共加载3次,每次加载前后都检查所有焊接部位。 加载分四个阶段进行: 第一阶段,在支架对应的0#梁段位置处按照支架应分摊的0#梁段钢筋混凝土重量的50%,取102.8t模拟加载,观察支架焊接、变形情况。

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个人事迹简介

个人事迹简介 我是来自计算机与与软件学院的学生,现在为青年志愿者协会的干事,在班级担任生活委员。在过去的一年里,我注重个人能力的培养积极向上,热心公益,服务群众,奉献社会,热忱的投身于青年支援者的行动中!一年时间虽短,但在这一年的时间里,作为一名志愿者,我确信我成长了很多,成熟了很多。“奉献、友爱、互助、进步”这是我们志愿者的精神,在献出爱心的同时,得到的是帮助他人的满足和幸福,得到的是无限的快乐与感动。路虽漫漫,吾将上下而求索!在以后的日子里,我会在志愿者事业上做的更好。 在思想上,我积极进取,关心国家大事,并多次与同学们一起学习志愿者精神,希望我们会在新的世纪里继续努力,发扬我国青年的光传统,不懈奋斗,不断创造,奋勇前进,为实现中华民族的伟大复兴做出了更大的贡献。 在学习上刻苦认真,抓紧时间,不仅学习好学科基础知识,更加学好专业课知识,在课堂上积极配合老师的教学,乐意帮助其它同学,有什么好的学习资料,学习心得也与他们交流,希望大家能共同进步。在上一个年度总成绩在班级排名第四,综合考评在班级排名第二。在工作中,我认真负责,出色的完成老师、同学交给的各项任务,所以班级人际关系良好。

此外参加了学院组织的活动,并踊跃地参加,发挥自己的特长,为班级争得荣誉。例如:参加校举办的大合唱比赛并获得良好成绩;参加了计算机与软件学院党校学习并顺利结业;此外,参加了计算机与软件进行的“计算机机房义务打扫与系统维护”的活动。在这些活动中体验到了大学生生活的乐趣。 现将多次参与各项志愿活动汇报如下:2013年10月26日,参加计算机与软件学院团总支实践部、计算机与软件学院青年志愿者协会组织“志愿者在五福家园的健身公园开展义务家教招新活动”;2013年11月7日,参加组成计算机与软件学院运动员方阵在田径场参加学院举办的学校运动会;2013年12月5日,参与学校学院组织的”一二.五“大合唱比赛;2014年3月12日,参加由宿舍站长组织义务植树并参与植树活动;2014年3月23日,在计算机与软件学院团总支书记茅老师的带领下,民俗文化传承协会、计算机与软件学院青年志愿者协会以及学生会的同学们参观了“计算机软件学院的文化素质教育共建基地--南京市民俗博物馆”的活动;2014年3月26日,参加有宿舍站长组织的“清扫宿舍公寓周围死角垃圾”的活动;2014年4月5日,参加由校青年志愿者协会、校实践部组织的“南京市雨花台扫墓”活动,2014年4月9日,作为班级代表参加计算机软件学院组织部组织的“计算机应用office操作大赛”的活动。 在参与各项志愿活动的同时,我的学习、工作、生活能力得到了提高和认可,丰富生活体验,提供学习的机会,提供学习的机会。

连续梁三级技术交底(0#块)(已修改)

编号: 交底内容连续梁施工日期 工程名称京沪上行线跨京沪高铁特大桥根据图号徐宿淮盐施桥(特)03-I(02) 一、连续梁施工主要工序 1、施工准备。 ⑴在底模拼装前,控制模板下方木标高复核设计要求,由测量组放出中线位置。 ⑵检查模板的几何尺寸,检查模板面是否平整、光洁、有无凹凸变形。 ⑶清除模板上的垃圾和杂物。 2、模板搭设。 ⑴底模 施工过程中,现场管理人员应对底模施工状态进行检查,模板班组根据现场管理人员对底模各项控制点测量、检查的结果进行相应调整。 ①技术状态检查 底模板铺设完成后,模板班组及时清理底模,工程部对底模平整度、预拱度设置、支座预偏量位置、底模长度、拼缝错台等情况进行检查。底模平整度采用1m靠尺检查,要求不平整度≤2mm/m。预拱度采用水准仪测量,支座预偏量位置采用全站仪测量,要求支座板位置高差≤1mm,并对同一支座板的四个角点、支座板范围内的平整度进行测量,要求其下座板的四角相对高差不大于2mm。底模长度采用在底模上放出预偏后的梁端线后用钢尺量测长度。 ②预埋件安装 底模上的预埋件有:支座板与防落梁预埋板,预埋板必须事先经过防腐处理,预埋件进场后,工程部、安质部应进行检查,检查预埋件的尺寸、套筒间距以及预埋板外露面平整度。 ③底模清理 底模清理宜在底模、侧模均安装调整好后进行,以防在检查调整侧模时被二次污染。 底模清理采用便携式鼓风机直接清理底板碎小杂物配合人工清理。 交底单位交底人 接收单位接收人

编号: 交底内容连续梁施工日期 工程名称京沪上行线跨京沪高铁特大桥根据图号徐宿淮盐施桥(特)03-I(02) 底模加工与安装尺寸允许偏差 序号检查项目允许偏差检验方法 1 底模全长±10mm 全站仪测量 2 底模支座中心线间距±5mm 全站仪测量 3 底模宽度+5mm,0 卷尺检查 4 底模预拱值偏差≤3mm 水平仪检查 5 底模板中心线与设计位置偏差≤2mm 全站仪检查 6 支座板处的任意两点高差≤1mm 水平尺检查 7 表面平整度≤2mm/m 1m靠尺检查 8 预留孔位置正确钢卷尺检查 ⑵侧模与翼板 ①模板拼装 侧模板与底板的连接采用圆弧倒角顺接后覆盖铁皮的方式,严格控制底板边界与腹板接头的位置准确性。腹板与腹板的拼接用双面胶密实。 ②模板清理及涂刷脱模剂 侧模全部调整就位后,对底、侧模面板同步进行清理,相应模板接缝则应在安装前即进行清理,确保接缝严密。底、侧模清理可采用人工用抹布清洁,如遇有锈蚀、浮浆难以清除,亦可采用钢丝圈打磨清理。在底模清理干净后,宜及时对面模涂刷脱模剂,脱模剂应涂刷均匀。 ③技术及质量控制 侧模技术控制除执行底模相同平整度检查外,还应对侧模保证桥梁高度、桥面宽度进行检查。 调整侧模顶部尺寸时,工程部技术员采用水准仪测量相同位置底模与翼缘板外侧顶面高差,高差须与设计梁高一致,偏差应满足:≤5mm。调整过程中,技术员置镜观测指导调整量,并且注意不可将水准仪置镜于正在调整模板上。两侧侧模均调整到位后,工程部技术员采用钢尺检查桥面宽度,桥面宽度允许偏差为±10mm,检查不应少于10点。 测量放样时工班长必须全程参与交接。

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