Predictive Supersymmetry from Criticality

a r X i v :h e p -p h /0611249v 2 4 D e c 2006UCB-PTH-06/20

LBNL-61989

Predictive Supersymmetry from Criticality

Yasunori Nomura and David Poland Department of Physics,University of California,Berkeley,CA 94720Theoretical Physics Group,Lawrence Berkeley National Laboratory,Berkeley,CA 94720Abstract Motivated by the absence of any direct signal of new physics so far,we present a simple supersymmetric model in which the up-type Higgs mass-squared parameter m 2H u crosses zero at a scale close to the weak scale.Such a theory may be motivated either by the conventional naturalness picture or by the landscape picture with certain assumptions on prior probability distributions of parameters.The model arises from a simple higher dimensional setup in which the gauge and Higgs ?elds propagate in the bulk while the matter ?elds are on a brane.The soft supersymmetry breaking parameters receive contributions from both moduli and anomaly mediations,and their weak scale values can be analytically solved for in terms of a single overall mass scale M .The expected size for M depends on whether one adopts the naturalness or landscape pictures,allowing for the possibility of distinguishing between these two cases.We also present possible variations of the model,and discuss more general implications of the landscape picture in this context.

1Introduction

Weak scale supersymmetry is an extremely attractive idea.It is based on a beautiful theoretical construction of enlarging the spacetime structure to anticommuting variables,and is supported indirectly by the successful uni?cation of gauge couplings at high energies[1].It also stabilizes the large hierarchy between the weak and the Planck scales due to a cancellation between the standard model and its superpartner contributions to the Higgs potential.In fact,this latter property has been one of the strongest motivations for weak scale supersymmetry.

From the experimental point of view,the most exciting aspect of weak scale supersymmetry is the existence of various superpartners at the TeV scale.Can we predict the spectrum of these superparticles?We already know,from the absence of a large new contribution to?avor changing neutral current and CP-violating processes,that the superparticle spectrum must have a certain special structure,such as?avor universality.Moreover,non-discovery of both superparticles and a light Higgs boson at LEP II puts strong constraints on the spectrum.This typically leads to?ne-tuning of order a few percent in reproducing the correct scale for electroweak symmetry breaking,and is called the supersymmetric?ne-tuning problem(for a recent analysis,see[2]).It seems plausible that successfully addressing this problem provides a key to the correct theory at the TeV scale,and to a fundamental mechanism or principle behind it.

There are two di?erent approaches towards the supersymmetric?ne-tuning problem.A con-ventional approach is to search for a model that is“natural.”In the context of the minimal supersymmetric standard model(MSSM),this amounts to looking for a model in which the su-persymmetry breaking mass-squared parameter for the up-type Higgs?eld,m2H

,is somehow

u suppressed at the weak scale,since the electroweak scale is determined approximately by

M2Higgs

the cosmological constant[6],and partly by the suggestion that string theory has an exponentially

large number of discrete nonsupersymmetric vacua[7],it has become increasingly plausible that

our universe is only one among a tremendous number of various universes,in which physical

constants can take vastly di?erent values.This“landscape”hypothesis may lead to a signi?cant

change in our notion of naturalness,and it is reasonable to consider the supersymmetric?ne-

tuning problem in this context.It has recently been argued that the landscape picture may lead to

a small hierarchy between the Higgs mass-squared parameter and the scale of superparticle masses

?m under certain assumptions on the probability distributions of various couplings and?m[8].

Speci?cally,under the existence of statistical“pressures”pushing?m towards larger values,the

relation v2～?m2/8π2may be obtained from environmental selection,where v is the electroweak scale.1Moreover,if the parameterμalso scans independently with?m and if the holomorphic

supersymmetry breaking Higgs mass-squared parameter,μB,is su?ciently small at a high scale,

then we obtain v2～|μ|2～|m2H u|～?m2/8π2.

It is interesting that the two di?erent pictures described above can both lead to a scenario in

crosses zero at a scale not much di?erent from which the supersymmetry breaking parameter m2H

u

the weak scale.In fact,the two pictures may not be totally unrelated.Suppose,for example,

that the ultraviolet theory at the gravitational or uni?cation scale gives universal scalar squared

masses m20(>0),as in the minimal supergravity scenario[11].In this case,the parameter m2H

u crosses zero at a renormalization scale of order the weak scale,as long as the gaugino masses are

small compared with|m20|1/2.This phenomenon is known as focus point behavior,and this class of theories was claimed to be natural[3],since|m2H

u|is relatively small at the weak scale and thus no strong cancellation is required between the two terms in the right-hand-side of Eq.(1).An

immediate criticism of this argument,based on the conventional viewpoint,is that if the value

of the top Yukawa coupling,y t,were di?erent,then the property of|m2H

u|being small at the weak scale would be destroyed—in other words,the fractional sensitivity of the weak scale,v,

to a variation of the top Yukawa coupling,?ln v2/?ln y t,is very large.This criticism,however,

is not appropriate if the property of|m2H

u|??m2at the weak scale is a result of environmental selection.In this case,if y t were changed,the scale of supersymmetry breaking masses,?m,would

also be changed in such a way that|m2H

u|～?m2/8π2??m2at the“new”weak scale～|m H u|. As a result,we always?nd|m2H

u|??m2at the“weak scale”regardless of the value of y t.The observed value of y t will then be determined as a result of(another)environmental selection,

presumably a combination of the consideration in[12]and others.

From the point of view of model-building,i.e.searching for the model describing physics above the TeV scale,we may then be motivated to look for a model in which|m2H

u|is suppressed compared with?m2at the weak scale,i.e.|m2H

u|crosses zero at a scale close to the weak scale. If this property arises without a strong cancellation between the“tree-level”and“radiative”

contributions to|m2H

u|,then we can consider that the model is natural in the conventional sense. Even if it arises due to a strong cancellation,however,the model may still be interesting since

it can arise as a result of environmental selection under certain circumstances.Note that the requirement of|m2H

u|being suppressed at the weak scale is di?erent from the one that the Higgs mass-squared parameter,|m2h|?|m2H u+|μ|2|,is suppressed at the weak scale,which should

always be the case.We are requiring that the cancellation(if any)must take place“inside”m2H

,

u and|μ|2.

and not between m2H

u

Since the condition of|m2H

u|??m2at the weak scale gives only one constraint on the large number of soft supersymmetry breaking masses,we clearly need other guiding principles to

narrow down the possibilities and obtain predictions on the superparticle masses.Without having a detailed knowledge of physics at the gravitational or uni?cation scale,we simply take the viewpoint that the physics at that scale should be“simple”–su?ciently simple that the resulting supersymmetry breaking masses also take a simple form.This clearly makes sense if we take the conventional“universe”picture,and may also be supported by the absence of large supersymmetric?avor-changing and CP-violating contributions(which would arise if the superparticle masses were chaotic).In the context of the“multiverse”(or landscape)picture, we merely hope that such a“simple”model is statistically preferred by the vacuum counting in the fundamental theory.In practice,if a su?ciently“simple”model de?ned at the high energy scale gives|m2H

u|??m2at the weak scale,we consider it interesting regardless of the level of

.

cancellation occurring in m2H

u

In this paper we present an example of such models.The model is very simple,and arises as a low-energy e?ective theory of higher dimensional theories in which the standard model gauge and Higgs?elds propagate in the bulk while matter?elds are con?ned on a(3+1)-dimensional brane.The compacti?cation scale is of the order of the uni?cation scale,and the low-energy e?ective theory below this scale is simply the MSSM.Upon stabilizing a volume modulus by a simple gaugino condensation superpotential,the superparticle masses in the low-energy theory receive contributions from both moduli and anomaly mediations.We?nd that

at a scale(very)close to the weak scale,satisfying the criterion this model gives vanishing m2H

u

described above.All the supersymmetry breaking parameters,except for the holomorphic Higgs mass-squared parameter,are predicted(essentially)in terms of a single overall mass parameter M,with the resulting spectrum showing a pattern distinct from conventional supergravity and gauge mediation models.This model gives a“non-hierarchical”spectrum of Mλ～m?f(=O(M)),

where Mλand m?

represent generic gaugino and sfermion masses,although variations of the f

model giving the“hierarchical”spectrum of Mλ～m?f/4π(～|μ|)may also be considered.The scale of the overall mass parameter M depends on which of the naturalness or landscape pictures we take,but will be generally in the range between O(v)and a multi-TeV scale.For the Higgs sector,we simply assume that the required structures for theμandμB parameters are prepared, presumably by statistical preference in the case that the landscape picture is adopted.

The paper is organized as follows.In the next section we present our model and derive predictions on the supersymmetry breaking masses which are independent of the picture adopted. In section3we discuss the implications of the model in both the“universe”and“multiverse”pictures,and argue that the di?erence can appear in the size of the overall mass scale for the superparticle masses.In section4we conclude by giving discussions on the issue of obtaining predictions for the superparticle masses in the landscape picture.In particular,we present several possible scenarios arising from a landscape of vacua in the“vicinity”of the particular model in section2,and elucidate under what conditions,or with what additional assumptions,the setup can give strong predictions on the superparticle spectrum.

2Model

In this section we present a simple model that has the property that the soft Higgs mass squared is vanishing at a scale close to the weak scale.We consider that physics above the uni?cation scale is higher dimensional,and that the standard model gauge and Higgs?elds propagate in the bulk while the matter?elds are localized on a(3+1)-dimensional brane.The low-energy e?ective theory is then given by the following4D supergravity action:

S= d4x√

T W aαW aα+C3W +h.c. ,(2)

4

where C is the chiral compensator super?eld,T is the moduli super?eld parameterizing the volume of the compact dimensions,and gμνis the metric in the superconformal frame.The super?elds H and M collectively represent the Higgs and matter?elds of the MSSM,i.e.H= H u,H d and M=Q i,U i,D i,L i,E i with i the generation index,and the superpotential W contains the usual MSSM Yukawa couplings W Yukawa.This setup naturally arises,for example,if grand uni?cation is realized in higher dimensions above the compacti?cation scale[13].2In Eq.(2),we

have assumed that moduli?elds other than T,e.g.ones parameterizing the shape of the compact dimensions,(if any)are absent in the low-energy theory.We have also assumed that higher order terms,e.g.terms involving powers of1/(T+T?),are su?ciently suppressed,which is technically natural since the theory is weakly coupled at the compacti?cation scale.

To obtain realistic phenomenology at low energies,the moduli?eld T must be stabilized.We assume that the stabilization superpotential for T takes the simple form arising from a single gaugino condensation.The superpotential W is then given by

W=W Yukawa+Ae?aT+c,(3)

where a is a real constant.The parameters A and c are constants of order unity and the gravitino mass(?1),respectively(in units of the4D gravitational constant M Pl?1018GeV, which is taken to be1).These parameters can be taken real in the presence of an approximate shift symmetry for Im T.Since the superpotential of Eq.(3)stabilizes the modulus T at a supersymmetry preserving anti-de Sitter vacuum,with T+T? ?2a?1ln(a/c),we need an uplifting(supersymmetry breaking)potential,which we take to be independent of T in the superconformal basis:

δS=? d4x√

D3branes,located at the bottom of a warped throat.(The con?guration of the gauge,Higgs and matter?elds described before corresponds to identifying them as D7-,D7-and D3-brane?elds,respectively.)

The minimization of the potential,derived from Eqs.(2–4),leads to supersymmetry breaking (F-term)expectation values for the compensator C and the modulus T:

F C

=m3/2,(5)

(T+T?)3/2

F T

m3/2≡M0,(6)

a(T+T?)

where m3/2is the gravitino mass.This implies that there is a little hierarchy between the sizes of F C and F T:

F C/C

(T+T?)=ln M Pl

2

localized strongly towards the SU(5)-violating brane.This reproduces the action of Eq.(2)at low energies while preserving the SU(5)understanding of the matter quantum numbers.

so that the supersymmetry breaking parameters in the MSSM receive comparable contributions from both moduli and anomaly mediations[15].Here,we have recovered the gravitational con-stant M Pl in the right-hand-side of Eq.(7).Note that the above Eqs.(5–7)are valid up to corrections of O(1/8π2)=O(1/ln(M Pl/m3/2)).

The supersymmetry breaking masses in the present model show the behavior of a reduced e?ective messenger scale,M mess,due to an interplay between the moduli and anomaly mediated contributions[16](for a simple proof,see[2]).By solving renormalization group equations at the one-loop level,the soft supersymmetry breaking masses at an arbitrary renormalization scaleμR are given by

M a(μR)=M0 1?b aμR ,(8) m2I(μR)=M20 r I?4 γI(μR)?1d lnμR ln M messμR ,(9) A IJK(μR)=M0 ?(r I+r J+r K)+2 γI(μR)+γJ(μR)+γK(μR) ln M mess

(M Pl/m3/2)1/2

,(11) where M U represents the compacti?cation scale,which is of the order of the uni?cation scale ≈1016GeV,and f is an O(1)coe?cient depending,e.g.,on A in Eq.(3).The parameter M0is de?ned in Eq.(6)and represents the overall mass scale for the supersymmetry breaking parameters.

The expressions of Eqs.(8–10)show that the supersymmetry breaking masses in this model take a very simple form:

M1=M2=M3=M0,(12)

m2?

Q i =m2?

U i

=m2?

D i

=m2?

L i

=m2?

E i

=0,m2H

u

=m2H

d

=M20,(13)

A u=A d=A e=?M0,(14)

-1000

100

200

300

400

500

600

700

800

1001000100001000001e+061e+071e+081e+091e+10

m a s s e s (G e V )μR (GeV )Supersymmetry breaking masses

Figure 1:Evolutions of soft supersymmetry breaking masses below M mess =5×109GeV for M 0=400GeV and tan β=10.Solid lines represent the gaugino masses (M 3,M 2and M 1from the top),dashed lines the ?rst two generation sfermion masses (m ?Q ,m ?U ,m ?D ,m ?L and m ?E from the top),and dotted lines the Higgs mass parameter (m H d and m H u from the top).Here,m Φ(Φ=?Q,?U,?D,?L,?E,H u ,H d )is de?ned by m Φ≡sgn(m 2Φ)|m 2Φ|1/2.The pole mass for the top quark is chosen to be the central value of the recently reported range m t =171.4±2.1GeV [19].at the e?ective messenger scale

M mess ?

4

Approximate ?avor universality for these corrections must be assumed in the case that M 0is not much larger than a TeV.

for illustrative purposes.In the?gure,we have taken the supersymmetry breaking masses of

Eqs.(12–14)at the scale M mess,and evolved them down using the one-loop renormalization

group equations of the MSSM.(The two-loop renormalization group equations have been used for

the supersymmetric parameters.)Note that while the soft supersymmetry breaking parameters

are depicted only forμR≤M mess,it should be understood that they are,in fact,generated at a scale of order M U.(The squark and slepton squared masses are negative at scales above M mess,

but this does not cause a problem since our vacuum is metastable at the time scale of the age of

the universe.)Below,we will choose M0and M mess to be free parameters of our analysis,since

these parameters have O(1)uncertainties that cannot be determined from the low-energy data

alone.The value of tanβis determined by the Higgs sector parameters,μandμB,whose origin

we leave unspeci?ed.5

A remarkable feature of the superparticle masses in Fig.1is that the up-type Higgs mass-

squared parameter crosses zero at the superparticle mass scale:

m2H

u

(μC)=0atμC?M0.(16)

While the precise value ofμC–the scale where m2H

u

crosses zero–depends on the values of

M mess and tanβ,it is of order M0for a wide range of these parameters.Note thatμC does not

depend on M0,since the renormalization group equations are homogeneous in M0.(If we take

M U to be a free parameter,instead of M mess,thenμC depends slightly on M0for a?xed M U,

through a weak dependence of M mess on M0.)In the example of M0=400GeV in Fig.1,the

value ofμC is within a factor of2from M0for M mess≈(109～1010)GeV for tanβ≈(5～30).(In fact,a value of M mess givingμC within a factor of2from M0can be found for tanβ≈(3～50). The mass squared for the right-handed stau,however,becomes negative at the weak scale for tanβ>～30.)These results do not change signi?cantly by including higher order e?ects,e.g.the two-loop renormalization group e?ects,or by varying the top quark mass within a2σrange of the recently reported value,m t=171.4±2.1GeV[19].At the leading order,we?nd from Eq.(9) that the scaleμC is given by

μC≈M mess exp 8π2 6y2t?3g22?

32g23y2t?36y4t+18g22y2t+3g42

≈10?7M mess,(17) where the top Yukawa coupling,y t,and the SU(3)C and SU(2)L gauge couplings,g3and g2,are evaluated at the scaleμR?μC,and we have neglected the small e?ects from the bottom Yukawa

0200400600800

100051015202530M a , m F ~, m H d (G e V )

tan βSupersymmetry breaking parameters (M a , m F ~, m H d

)0

200400600800100051015202530

?A t ,b ,τ, m F ~3

(G e V )

tan βSupersymmetry breaking parameters (?A t,b,τ, m F ~3

)Figure 2:Predictions for the soft supersymmetry breaking parameters as a function of tan βfor M 0=400GeV.The left panel shows the predictions for the gaugino masses (solid;M 3,M 2and M 1from the top),the ?rst two generation sfermion masses (dashed;m ?Q ,m ?U ,m ?D ,m ?L and m ?E from the top),and the down-type Higgs boson mass m H d (dotted).The right panel shows those

for the third generation scalar trilinear interaction parameters (solid;A b ,A t and A τfrom the top)and the third generation sfermion masses (dashed;m ?D 3,m ?Q 3,m ?U 3,m ?L 3and m ?E 3from the top).For A t ,A b and A τ,which are negative,the absolute values are plotted.The scalar trilinear interaction parameters for the ?rst two generations,A u ,A d and A e ,are not shown.

coupling,y b ,and the U (1)Y gauge coupling,g 1.To obtain μC ?M 0,a larger M 0requires a larger M mess ∝M 0.For fundamental parameters of the theory,this implies f ∝M 0(see Eq.(11)).

Since the superparticle mass scale M 0is close to μC ,we can evaluate the soft supersymmetry breaking parameters at the superparticle mass scale M 0approximately by substituting Eq.(17)into Eqs.(12–14).This gives predictions for all the supersymmetry breaking masses,except for the holomorphic Higgs mass-squared parameter μB (and m 2H u ),in terms of the overall mass

scale M 0and the running gauge and Yukawa couplings at that scale.Note that we even do not have to know the value of M mess –for given values of M 0and tan β,which we need to obtain the values of the Yukawa couplings,we can predict all the supersymmetry breaking parameters with the assumption of Eq.(16).

In Fig.2,we present the predicted values of the supersymmetry breaking parameters for M 0=400GeV as a function of tan β.The left panel shows the predictions of the gaugino masses,M a ,the ?rst two generation sfermion masses,m ?F ,and the down-type Higgs boson mass,m H d .The right panel shows the third generation scalar trilinear interaction parameters,A t,b,τ,and the third generation sfermion masses,m ?F 3.The scalar trilinear interaction parameters for

the ?rst two generations,A u,d,e ,are not shown.The predictions for M a ,m ?F ,m ?Q 3,m ?U 3,m ?L 3,

A t(and A u,which is not shown)are rather insensitive to the value of tanβ,while those for

m H

d ,m?

D3

,m?

E3

,A b,Aτ(and A d,A e)have weak sensitivities to tanβ.(The sensitivity is strong

for m?

E3

for tanβ>～30where it approaches zero.)For tanβ～10,the predicted ratios among the soft supersymmetry breaking parameters(including the?rst two generation scalar trilinear interaction parameters)are given by

M1:M2:M3:m?

Q :m?

U

:m?

D

:m?

L

:m?

E

:m?

Q3

:m?

U3

:m?

D3

:m?

L3

:m?

E3

:

m H

d

:?A u:?A d:?A e:?A t:?A b:?Aτ

?0.71:0.91:1.8:1.5:1.4:1.4:0.52:0.30:1.3:1.1:1.4:0.51:0.28:

1.1:

2.2:2.6:1.3:1.7:2.5:1.

3.(18) Here,we have presented the numbers in units of M0.Note that these numbers are subject to errors of O(10%),coming from“higher order”e?ects,for quantities associated with the colored superparticles.(The errors for quantities that are not associated with the colored superparticles are smaller.)In the case that we take the“universe”picture,these e?ects include the fact that the superparticle mass scale M0does not“coincide”withμC,although the two are of the same order.This source of errors does not exist if we adopt the“multiverse”picture,where M0and μC are very close.

The predictions of Eq.(18)have a sensitivity to the value of M0,but only through the running of the gauge and Yukawa couplings.As a result,these predictions,and the predictions for the ratios of the supersymmetry breaking masses obtained from Fig.2,are valid in a wide range of M0with only small corrections.In the case that M0is in a multi-TeV region(as will be the case in the“multiverse”picture;see the next section),the corrections are still smaller than about 10%.For example,the predictions of Eq.(18)change for M0=3TeV to

M1:M2:M3:m?

Q :m?

U

:m?

D

:m?

L

:m?

E

:m?

Q3

:m?

U3

:m?

D3

:m?

L3

:m?

E3

:

m H

d

:?A u:?A d:?A e:?A t:?A b:?Aτ

?0.63:0.90:1.8:1.5:1.4:1.4:0.56:0.33:1.3:1.0:1.4:0.56:0.31:

1.1:

2.2:2.7:1.4:1.8:2.5:1.4,(19) but these are not much di?erent from the ones in Eq.(18).

We?nally discuss the Higgs sector of the model.To have the correct electroweak sym-metry breaking phenomenology,theμandμB parameters must be of order the weak scale. In particular,the classical contribution to B≡μB/μof order the gravitino mass must be suppressed.Here we simply assume that the value of B is su?ciently suppressed,for exam-ple the case that B is somehow dominated by the quantum(anomalous)contribution:B= 2M0{γH u(μR)+γH d(μR)}ln(M mess/μR).(This expression for B is,in fact,a solution to the

one-loop renormalization group equation.)We may also consider the case that μis generated by the expectation value of a singlet ?eld through W =λSH u H d (at least in the context of the “universe”picture),whose e?ect on the evolutions of the Higgs soft masses are suppressed if the value of λis su?ciently small.

3Implications

We have seen that the model given by Eqs.(2,3,4)provides the predictions of Eq.(18),which depend only very weakly on the values of tan βand M 0(see Fig.2and Eq.(19)).The expected range for the overall scale M 0,however,di?ers depending on the scenario we consider.In this section we discuss this issue,as well as other phenomenological implications of the model.Let us ?rst take the conventional “universe”picture,i.e.the overall scale M 0does not e?ectively “scan.”In this case,our guiding principle will be “naturalness,”i.e.the observed scale of electroweak symmetry breaking,v ?174GeV,should be a “typical”value in the parameter space of the model.For ?xed values of the supersymmetric couplings,this is rather clear in our model because of the suppression of m 2H u relative to the other soft masses at the weak

scale.(We assume that the Higgs sector is arranged such that there is no large μB term of order μm 3/2.)Naturalness of the model becomes clearer when compared with other,typical supersymmetry breaking models.Consider,for example,a model in which the supersymmetry breaking parameters of Eqs.(12–14)are generated at the uni?cation scale,M U ≈1016GeV,as in the pure moduli mediated model of [18].In this case,the size of the up-type Higgs mass squared |m 2H u |,relative to the other soft masses,is much larger at the weak scale.(The evolutions

of soft masses in the two models are depicted in Fig.3.)An important point is that while |m 2H u |keeps increasing towards the infrared from the scale μC where m 2H u crosses zero,dragged by

increasing M 3through g 3and y t ,the right-handed slepton masses m ?E stay almost constant,as they receive only small contributions through g 1.As a consequence,if the crossing scale μC is

much larger than the weak scale,we would obtain a hierarchy |m 2H u |/m 2?E ?1at the weak scale (see Fig.3b),leading to ?ne-tuning between the m 2H u and |μ|2terms in Eq.(1)under the LEP II

constraint of m ?E >～100GeV.Our model avoids this because μC is close to the weak scale (see Fig.3a).

Since there is no particular reason that μC is extremely close to the scale of superparticle masses,|μC ?M 0|/M 0?1,we expect that there is some discrepancy between the two quantities,e.g.|ln(μC /M 0)|=O (1).The value of m 2H u at the weak scale is then not much smaller than m 2?E ,so that the overall scale M 0is not much larger than the weak scale to avoid ?ne-tuning in Eq.(1).We typically expect 400GeV <～M 0<～1TeV,where the lower bound comes from m ?E >～100GeV.With these values of M 0,the physical mass for the lightest neutral Higgs boson,M Higgs ,can

-400-200

020*******

800100100001e+061e+081e+101e+121e+141e+16m a s s e s (G e V )μR (GeV )(a)-600-400

-200

200

400

600

800

1000

1200

100100001e+061e+081e+101e+121e+141e+16

m a s s e s (G e V )μR (GeV )(b)Figure 3:Evolutions of soft supersymmetry breaking masses in the model of section 2(the left panel),and in the model where the supersymmetry breaking parameters of Eqs.(12–14)are given at the uni?cation scale,M U ≈1016GeV (the right panel).Here,we have taken M 0=400GeV and tan β=10in both cases.Solid lines represent the gaugino masses (M 3,M 2and M 1from the top),dashed lines the ?rst two generation sfermion masses (m ?Q ,m ?U ,m ?D ,m ?L and m ?E from the top),and dotted lines the Higgs mass parameter (m H d and m H u from the top).

easily exceed the experimental lower bound of M Higgs >～114GeV [20].This is because our model provides a relatively large value of A t at the weak scale,so that we can avoid the Higgs-boson mass bound with relatively small top squark masses.(The importance of large A t in reducing ?ne-tuning was particularly emphasized in Refs.[5,2].)In Fig.4we plot M Higgs ,calculated using FeynHiggs 2.4.1[21],as a function of M 0for tan β=5(dotted line)and tan β=10(solid line).The μparameter is chosen to be μ=150GeV arbitrarily,but the dependence of the result on μis very weak.From the ?gure,we expect that M Higgs <～120GeV.The value of B

is given by B ≈M 20/μtan β,so that the preferred tan βrange of 5<～tan β<～20requires a

somewhat small value of B of order 0.1M 20/μ.The sensitivity of the weak scale to variations of

the supersymmetric parameters is also not so large in this model,since there is no superparticle that has a particularly large mass compared with others.The lightest supersymmetric particle (LSP)is either (a neutral component of)the Higgsino or the right-handed stau.In the former case the LSP may be the dark matter of the universe if it is produced nonthermally.In the latter case it will have to decay into some neutral particle,e.g.the axino –the supersymmetric partner of the axion,which may compose the dark matter.

Let us now turn to the case that we adopt the “multiverse,”or the “landscape,”picture.More precisely,we now assume that the overall supersymmetry breaking parameter M 0has di?erent values in di?erent “parts”of the multiverse,or in di?erent vacua of the theory,with larger

108110

112

114

116

118120

122

124

126400600800100012001400160018002000

M H i g g s (G e V )M 0 (GeV )The lightest Higgs boson mass

Figure 4:Physical Higgs boson mass M Higgs as a function of M 0for tan β=5(dotted line)and tan β=10(solid line).The μparameter is chosen to be μ=150GeV.The horizontal dashed line represents the experimental lower bound of M Higgs ?114GeV.

values preferred by some positive power n :dP ∝dM n 0,where P is the probability distribution

function.In general the distribution of M 0depends on the structure of the supersymmetry breaking (uplifting)sector and the sector that produces the constant term c in the superpotential,

and the assumption of dP ∝dM n 0corresponds typically to tree-level supersymmetry breaking

(since tree-level supersymmetry breaking naturally prefers larger breaking scales).Note that since environmental selection “locks”the value of d in Eq.(4)as d ≈|c |2,through the condition for the cosmological constant being small [6],all the supersymmetry breaking parameters (including the ones generated through direct interactions with the uplifting sector,if any)scale in a similar way.As discussed in Ref.[8],this leads to a small hierarchy between the weak scale and the scale

of the sfermion masses.With the statistical pressure of dP ∝dM n 0,the sfermion masses ?m are

pushed towards larger values,but not beyond the scale where the Higgs mass-squared parameter m 2h crosses zero,since a larger ?m

would lead to the recovery of electroweak symmetry in the Higgs sector,a situation hostile to the existence of observers.This leads to |m 2h |=O (?m 2/8π2)??m 2,since m 2h becomes zero around the scale ?m

.Moreover,if the parameter μscans independently,and if the parameter B is su?ciently small at a high scale,then we obtain |μ|2=O (?m 2/8π2)??m 2

and thus also |m 2H u |=O (?m

2/8π2)??m 2—the property we found in our model (see Eq.(16)).In order for this argument to be signi?cant,the model must satisfy the conditions for μand B given above,which we assume to be the case.An implication of this picture is then that the overall

scale parameter M0is expected to be somewhat larger than the weak scale:M20/8π2～|m2H u|～|μ|2～v2.The precise hierarchy depends on the strength of the pressure n,but we generically expect M0to be in a multi-TeV region.This implies that in this picture all the superparticles, other than the Higgsinos,as well as all the CP-odd,the heavier CP-even,and the charged Higgs bosons,A0,H0and H±,have masses in this region(～M0>～1TeV).The ratios between the superparticle masses are still given by Eq.(19),and the three Higgs boson masses are given by

.

m A0～m H0～m H±～m H

d

The spectrum just described can lead to quite distinct phenomenology.For example,if M0 is somewhat large,e.g.M0>～2TeV,all the superparticles and heavier Higgs bosons are beyond the discovery reach of the LHC,except for the Higgsinos.Thus,the LHC will e?ectively see the (one Higgs doublet)standard model,plus possibly the Higgsinos.Discoveries of superparticles, however,may be possible if M0is lower.The LSP is the neutral component of the Higgsinos, which may be the dark matter of the universe.For example,if M0?3TeV,the gravitino mass is m3/2?100TeV,and the moduli?eld mass is m T=O(1000～10000TeV).The moduli ?eld is expected to dominate the energy density of the early universe,and then it decays into the superparticles and gravitinos,which in turn decay into the LSP.With these masses,the constraint from big-bang nucleosynthesis can be avoided(see e.g.[22])and the LSP may compose the dark matter,presumably with some(small)amount of dilution of its energy density.Alternatively, the LSP may decay into a lighter particle,e.g.the axino.

4Discussions:Predictions from the Landscape?

Since it has been di?cult to?nd ways of experimentally“testing”the landscape picture,it is important to consider what implications it can have on the low-energy spectrum and what predic-tions we can get from it when combined with additional assumptions.In this paper we discussed a framework which may either arise from the naturalness consideration in the conventional pic-ture or from the landscape picture under certain circumstances,and presented an example model which leads to strong predictions of the superparticle masses.The essential ingredients of the framework were

(i)The up-type Higgs mass-squared parameter m2H

crosses zero at a scale close to the super-

u

particle mass scale.

(ii)The structure of the theory at the uni?cation(or compacti?cation)scale is“simple”as far as the observable sector is concerned.

The reason that this can lead to strong predictions,despite the fact that each ingredient is not necessarily giving a very strong constraint,is that a generic theory satisfying(ii)does not typically lead to the property of(i),so that the combination of these two criteria can be a very strong

constraint on models.The model we presented has a fairly simple structure at the uni?cation scale,arising from a simple setup in higher dimensions,and yet gives a vanishing m2H

u

at a scale close to the weak scale.All the supersymmetry breaking parameters,except for the holomorphic Higgs mass-squared parameterμB(and m2H

u

),are predicted in terms of a single overall mass scale M0(and tanβ= H u / H d ).The parameter M0is expected to be in a multi-TeV region if it scans with a preference towards larger values.

On the other hand,it is clear that the speci?c model discussed above is not a unique model satisfying(i)and(ii).For example,we can consider the situation in which the scalar masses are approximately universal at a high scale,with somewhat suppressed gaugino masses.As observed in[3],this leads to suppressed m2H

u

at the weak scale.In fact,this situation can be realized in the setup of Eqs.(3,4)if the supersymmetry breaking(uplifting)sector gives universal scalar masses through direct interactions with the observable sector?elds.6In the context of the landscape picture,with a statistical pressure acting towards larger values for the supersymmetry breaking masses,this can lead to relatively degenerate scalar masses in a multi-TeV region and gaugino masses in a few hundred GeV region,with the relative gaugino masses still given by Eq.(18).The Higgsino masses are comparable to the gaugino masses,and the value of tanβwill be relatively large of O(10),for an unsuppressed B parameter.(The possibility of a relatively unsuppressed B parameter is an advantage of unsuppressed scalar masses.)In either of these models,the spectrum of superparticles is special such that it leads to a suppressed value of m2H

u

at the weak scale,which appears to us as a result of an accidental cancellation due to the speci?c values of the observed gauge and Yukawa couplings.

While the conditions of(i)and(ii)are keys to obtain strong predictions for the superparticle spectrum,neither is a necessary consequence of the landscape picture.Indeed,it is possible that environmental selection leads to the Higgs mass-squared parameter being small due to

cancellation between m2H

u andμ2,and not just inside m2H

u

,in which case(i)is not necessarily

satis?ed.Moreover,a simple ultraviolet structure may not be preferred by the statistics of landscape vacua,and the condition(ii)may also be violated.In these cases we lose a strong constraint on the superparticle spectrum,reducing predictivity,but may still get an interesting pattern for the spectrum.For example,landscape statistics may prefer the case in which the supersymmetry breaking(uplifting)sector gives somewhat random scalar masses through direct interactions with the observable sector,in the setup of Eqs.(3,4).(Flavor universality may still have to be assumed unless these masses are very large.)With the statistical pressure of pushing the overall mass scale to larger values,we?nd the Higgs mass-squared parameter somewhat suppressed compared with the scalar superparticle masses.The spectrum will then contain the

scalar superparticles and the Higgsinos in a multi-TeV region,whose masses do not obey simple relations.The gaugino masses,however,may still be of order a few hundred GeV and obey Eq.(18)in the case that the direct e?ect from the supersymmetry breaking sector is suppressed in the gauge kinetic functions.Deviations from Eq.(18),however,can also occur,e.g.,if the moduli-stabilization and uplifting sectors deviate from the minimal form of Eqs.(3,4),in which case the gaugino masses unify at a scale that is not necessarily the intermediate scale of Eq.(15), or if the direct e?ect is not suppressed in the gauge kinetic functions,in which case the gaugino masses are of order a multi-TeV.The value of tanβwill generically be of O(1)for an unsuppressed value for the B parameter.

To summarize,we have argued that both the conventional naturalness picture and the land-

crosses zero scape picture(with certain assumptions)may point to a scenario in which m2H

u

near the weak https://www.sodocs.net/doc/7015172756.html,bining this constraint with a simple ultraviolet structure can lead to a highly predictive superparticle spectrum,an example being the model presented in section2.The model predicts all the supersymmetry breaking parameters,except for the holomorphic Higgs

),in terms of a single overall mass scale M0(with a weak mass-squared parameterμB(and m2H

u

dependence on tanβ).This parameter is expected to be of order a few hundred GeV if it does not scan but in a multi-TeV region if it does scan,allowing for the possibility of experimentally distinguishing between these two cases.We have also discussed implications of the landscape picture on the supersymmetry breaking masses in a general setup arising from Eqs.(3,4)with possible additional interactions.Depending on the form of these interactions,strong predictions on the entire superparticle masses may be lost,but some predictions,such as those on the gaug-ino masses,may still be preserved.It is interesting that the experimental observation of one of these spectra may hint at possible statistical pressures acting on parameters of the theory,and thus the gross structure of vacua in the“vicinity”of our own one.

Acknowledgments

We thank Lawrence Hall for discussions.This work was supported in part by the Director,O?ce of Science,O?ce of High Energy and Nuclear Physics,of the US Department of Energy under Contract DE-AC02-05CH11231.The work of Y.N.was also supported by the National Science Foundation under grant PHY-0555661,by a DOE Outstanding Junior Investigator award,and by an Alfred P.Sloan Research Fellowship.

References

[1]S.Dimopoulos and H.Georgi,Nucl.Phys.B193,150(1981);N.Sakai,Z.Phys.C11,153

(1981);S.Dimopoulos,S.Raby and F.Wilczek,Phys.Rev.D24,1681(1981).

[2]R.Kitano and Y.Nomura,Phys.Rev.D73,095004(2006)[arXiv:hep-ph/0602096].

[3]J.L.Feng,K.T.Matchev and T.Moroi,Phys.Rev.Lett.84,2322(2000)[arXiv:hep-

ph/9908309];Phys.Rev.D61,075005(2000)[arXiv:hep-ph/9909334].

[4]K.Choi,K.S.Jeong,T.Kobayashi and K.i.Okumura,Phys.Lett.B633,355(2006)

[arXiv:hep-ph/0508029].

[5]R.Kitano and Y.Nomura,Phys.Lett.B631,58(2005)[arXiv:hep-ph/0509039].

[6]S.Weinberg,Phys.Rev.Lett.59,2607(1987);H.Martel,P.R.Shapiro and S.Weinberg,

Astrophys.J.492,29(1998)[arXiv:astro-ph/9701099].

[7]R.Bousso and J.Polchinski,JHEP0006,006(2000)[arXiv:hep-th/0004134];L.Susskind,

arXiv:hep-th/0302219;M.R.Douglas,JHEP0305,046(2003)[arXiv:hep-th/0303194];and references therein.

[8]G.F.Giudice and R.Rattazzi,Nucl.Phys.B757,19(2006)[arXiv:hep-ph/0606105].

[9]N.Arkani-Hamed and S.Dimopoulos,JHEP0506,073(2005)[arXiv:hep-th/0405159];

G.F.Giudice and A.Romanino,Nucl.Phys.B699,65(2004)[Erratum-ibid.B706,

65(2005)][arXiv:hep-ph/0406088].

[10]See,e.g.,B.Feldstein,L.J.Hall and T.Watari,arXiv:hep-ph/0608121.

[11]A.H.Chamseddine,R.Arnowitt and P.Nath,Phys.Rev.Lett.49,970(1982);R.Barbieri,

S.Ferrara and C.A.Savoy,Phys.Lett.B119,343(1982);L.J.Hall,J.Lykken and S.Weinberg,Phys.Rev.D27,2359(1983).

[12]V.Agrawal,S.M.Barr,J.F.Donoghue and D.Seckel,Phys.Rev.D57,5480(1998)

[arXiv:hep-ph/9707380].

[13]Y.Kawamura,Prog.Theor.Phys.105,999(2001)[arXiv:hep-ph/0012125];L.J.Hall and

Y.Nomura,Phys.Rev.D64,055003(2001)[arXiv:hep-ph/0103125];Annals Phys.306, 132(2003)[arXiv:hep-ph/0212134].

[14]S.Kachru,R.Kallosh, A.Linde and S.P.Trivedi,Phys.Rev.D68,046005(2003)

[arXiv:hep-th/0301240].

[15]K.Choi,A.Falkowski,H.P.Nilles,M.Olechowski and S.Pokorski,JHEP0411,076(2004)

[arXiv:hep-th/0411066];K.Choi,A.Falkowski,H.P.Nilles and M.Olechowski,Nucl.Phys.

B718,113(2005)[arXiv:hep-th/0503216].

[16]K.Choi,K.S.Jeong and K.i.Okumura,JHEP0509,039(2005)[arXiv:hep-ph/0504037].

[17]P.Skands et al.,JHEP0407,036(2004)[arXiv:hep-ph/0311123].

[18]R.Barbieri,L.J.Hall and Y.Nomura,Phys.Rev.D66,045025(2002)[arXiv:hep-

ph/0106190];Nucl.Phys.B624,63(2002)[arXiv:hep-th/0107004].

[19]E.Brubaker et al.[Tevatron Electroweak Working Group],arXiv:hep-ex/0608032.

[20]R.Barate et al.[ALEPH Collaboration],Phys.Lett.B565,61(2003)[arXiv:hep-

ex/0306033];LEP Higgs Working Group Collaboration,arXiv:hep-ex/0107030.

[21]S.Heinemeyer,W.Hollik and G.Weiglein,https://www.sodocs.net/doc/7015172756.html,mun.124,76(2000)

[arXiv:hep-ph/9812320];Eur.Phys.J.C9,343(1999)[arXiv:hep-ph/9812472].

[22]T.Asaka,S.Nakamura and M.Yamaguchi,Phys.Rev.D74,023520(2006)[arXiv:hep-

ph/0604132];M.Endo,K.Hamaguchi and F.Takahashi,Phys.Rev.Lett.96,211301(2006) [arXiv:hep-ph/0602061].

[23]H.Abe,T.Higaki,T.Kobayashi and Y.Omura,arXiv:hep-th/0611024.

工程测试技术试题及答案

工程测试技术试题及答案Last revision on 21 December 2020

复习总结 一、概念题 1.测试过程中，若所测试的信号不随时间变化或变化非常缓慢，称这种测试称为静态 测试。如果所测试的信号随时间周期变化或变化很快，这种测试称为动态测试。 2.传感器是把被测量转换成易于变换、传输和处理的一种器件或装置。 3.按构成原理分类，电阻应变片、热敏电阻、压电晶片属物性型传感器。 4.按构成原理分类，电容传感器、自感型电感式传感器属结构型传感器。 5.为提高和改善传感器的技术性能，可采取以下技术措施：差动技术、平均技术以及 补偿与修正技术。 6.传感器的定度曲线（或标定曲线）与拟合直线之间的偏离程度称为传感器的线性 度。 7.传感器的灵敏度是指稳态时，输出变化量与输入变化量之间的比值。 8.对于一阶传感器系统，当其时间常数（或τ）越小，其频率响应特性越好。 9.激波管标定系统中，激波管的作用是一种动态标定设备，能产生阶跃压力信号输 出。 10.金属电阻应变片的规格一般以面积（或长×宽）和初始阻值表示。 11.用电阻应变片测量构件的变形，影响电阻应变片电阻变化的因素有：应变片的灵敏 度和初始阻值、被测构件的应变量、以及应变片沿构件的粘贴方向。（因为：△R=KεR，K为灵敏度，R为应变片初始阻值，ε被测构件的应变量） 12.将电阻丝绕成应变片后，由于存在横向效应，其灵敏系数一般会减小。 13.在电桥测量中，由于电桥接法不同，输出电压的灵敏度也不同，全桥接法可以得到 最大灵敏度输出。 14.应变片的温度误差补偿方法通常可分为：桥路补偿法、应变片自补偿法。 15.根据工作原理，变气隙型自感式传感器的灵敏度具有理论上的非线性。 16.电涡流接近开关结构简单，根据其工作原理，不可用来进行类似如玻璃瓶、塑料零 件以及水的液位的检测。 17.在差动式自感传感器中，若采用交流桥路为变换电路，常出现零点残余电压现象， 该现象使传感器灵敏度下降，灵敏阈值增大，非线性误差增大。

控制软件说明书

控制软件说明书 PC端软件FTM 安装及应用 系统运行环境： 操作系统中英文Windows 98/2000/ NT/XP/WIN7/ Vista， 最低配置 CPU：奔腾133Mhz 内存：128MB 显示卡：标准VGA，256色显示模式以上 硬盘：典型安装 10M 串行通讯口：标准RS232通讯接口或其兼容型号。 其它设备：鼠标器 开始系统 系统运行前，确保下列连线正常： 1：运行本软件的计算机的RS232线已正确连接至控制器。 2：相关控制器的信号线，电源线已连接正确； 系统运行步骤： 1：打开控制器电源，控制电源指示灯将亮起。 绿色，代表处于开机运行状态；橙色代表待机状态。 2. 运行本软件 找到控制软件文件夹，点击FWM.exe运行。出现程序操作界面：

根据安装软件版本不同，上图示例中的界面及其内容可能会存在某些差别，可咨询我们的相关的售后服务人员。 上图中用红色字体标出操作界面的各部分的功能说明： 1. 菜单区：一些相关的菜单功能选择执行区。 2. 操作区：每一个方格单元代表对应的控制屏幕，可以通过鼠标或键盘的点选，拖拉的方式选择相应控制单元。 3.功能区：包含常用的功能按钮。 4.用户标题区：用户可根据本身要求，更改界面上的标题显示 5.用户图片区：用户可根据本身要求，更改界面上的图片显示，比如公司或工程相关LOGO图片。 6.附加功能区：根据版本不同有不同的附加项目。 7.状态区：显示通讯口状态，操作权限状态，和当前的本机时间，日期等。 如何开始使用 1. 通讯设置 单击主菜单中“系统配置”――》“通讯配置” 选择正确的通讯端口号，系统才能正常工作。 可以设置打开程序时自动打开串口。 2.系统配置

螺纹通止规

螺纹通止规 定是:螺纹止规进入螺纹不能超过2.5圈,一般的要实际不得超过2圈,并且用得力度不能大,我们的经验是用拇指和食指轻轻夹持螺纹规以刚好能转动螺纹规的力度为准.力大了就相当于在使用丝锥或牙板了,那样规就用不了几次了. 螺纹通止规 螺纹通止规是适用于标准规定型号的灯头作为灯用附件电光源产品时候的设计和生产、检验的工具设备。 用途 一般用于检验螺纹灯头或灯座的尺寸是否符合标准要求，分别检验螺纹灯头的通规和止规尺寸或灯座的通规或止规尺寸。 工作原理 具体检验要求及介绍详见中国人民国国家标准：GB/T1483.1-2008或 IEC60061-3:2004标准规定容。 操作方法 具体检验要求及介绍详见中国人民国国家标准：GB/T1483.1-2008或 IEC60061-3:2004标准规定容。 通止规

通止规，是量规的一种。作为度量标准，用于大批量的检验产品。 通止规是量具的一种，在实际生产批量的产品若采取用计量量具（如游标卡尺，千分表等有刻度的量具）逐个测量很费事．我们知道合格的产品是有一个度量围的.在这个围的都合格，所以人们便采取通规和止规来测量． 通止规种类 （一）对统一英制螺纹，外螺纹有三种螺纹等级：1A、2A和3A级，螺纹有三种等级：1B、2B和3B级，全部都是间隙配合。等级数字越高，配合越紧。在英制螺纹中，偏差仅规定1A和2A级，3A级的偏差为零，而且1A和2A级的等级偏差是相等的等级数目越大公差越小，如图所示：1B 2B 3B 螺纹基本中径3A 外螺纹2A 1A 1、1A和1B级，非常松的公差等级，其适用于外螺纹的允差配合。 2、2A和2B级，是英制系列机械紧固件规定最通用的螺纹公差等级。 3、3A和3B级，旋合形成最紧的配合，适用于公差紧的紧固件，用于安全性的关键设计。 4、对外螺纹来说，1A和2A级有一个配合公差，3A级没有。1A级公差比2A级公差大50，比3A级大75，对螺纹来说，2B级公差比2A公差大30。1B级比2B级大50，比3B级大75。 （二）公制螺纹，外螺纹有三种螺纹等级：4h、6h和6g，螺纹有三种螺纹等级：5H、6 H、7H。（日标螺纹精度等级分为I、II、III三级，通常状况下为II级）在公制螺纹中，H 和h的基本偏差为零。G的基本偏差为正值，e、f和g的基本偏差为负值。如图所示：公差G H 螺纹偏差基本中径外螺纹f g h e 1、H是螺纹常用的公差带位置，一般不用作表面镀层，或用极薄的磷化层。G位置基本偏差用于特殊场合，如较厚的镀层，一般很少用。 2、g常用来镀6-9um的薄镀层，如产品图纸要6h的螺栓，其镀前螺纹采用6g的公差带。 3、螺纹配合最好组合成H/g、H/h或G/h，对于螺栓、螺母等精制紧固件螺纹，标准推荐采用6H/6g的配合。 （三）螺纹标记M10×1–5g 6g M10×1–6H 顶径公差代号中径和顶径公差代号（相同）中径公差代号。 通止规是两个量具分为通规和止规．举个例子：M6－7h的螺纹通止规一头为通规（T）如果能顺利旋进被测螺纹孔则为合格，反之不合格需返工（也就是孔小了）．然后用止规（Z）如果能顺利旋进被测螺纹孔2.5圈或以上则为不合格反之合格．且此时不合格的螺纹孔应报废，不能进行返工了．其中2.5圈为国家标准，若是出口件最多只能进1.5圈（国际标准）．总之通规过止规不过为合格，通规止规都不过或通规止规都过则为不合格。

感官动词和使役动词

感官动词和使役动词 默认分类2010-05-28 23:14:26 阅读46 评论0 字号：大中小订阅 使役动词，比如let make have就是3个比较重要的 have sb to do 没有这个用法的 只有have sb doing.听凭某人做某事 have sb do 让某人做某事 have sth done 让某事被完成（就是让别人做） 另外： 使役动词 1.使役动词是表示使、令、让、帮、叫等意义的不完全及物动词,主要有make(使,令), let(让), help(帮助), have(叫)等。 2.使役动词后接受词,再接原形不定词作受词补语。 He made me laugh. 他使我发笑。 I let him go. 我让他走开。 I helped him repair the car. 我帮他修理汽车。 Please have him come here. 请叫他到这里来。 3.使役动词还可以接过去分词作受词补语。 I have my hair cut every month. 我每个月理发。 4.使役动词的被动语态的受词补语用不定词,不用原形不定词。 (主)He made me laugh. 他使我笑了。 (被)I was made to laugh by him. 我被他逗笑了。 使役动词有以下用法： a. have somebody do sth让某人去做某事 ??i had him arrange for a car. b. have somebody doing sth.让某人持续做某事。 ??he had us laughing all through lunch. 注意：用于否定名时，表示“允许” i won't have you running around in the house. 我不允许你在家里到处乱跑。 ******** 小议“使役动词”的用法 1. have sb do 让某人干某事 e.g:What would you have me do? have sb/sth doing 让某人或某事处于某种状态，听任 e.g: I won't have women working in our company. The two cheats had the light burning all night long. have sth done 让别人干某事，遭受到 e.g:you 'd better have your teeth pulled out. He had his pocket picked. notes: "done"这个动作不是主语发出来的。 2.make sb do sth 让某人干某事 e.g:They made me repeat the story. What makes the grass grow?

传感器与检测技术考试试题及部分答案(DOC)

全国2001年10月自学考试传感器与检测技术试卷 课程代码：02202 第一部分选择题（共24分） 一、单项选择题（本大题共12小题，每小题2分，共24分）在每小题列出的四个选项中只有一个选项是 符合题目要求的，请将正确选项前的字母填在题后的括号内。错选、多选和未选均无分。 1．下列被测物理量适合于使用红外传感器进行测量的是（C ） A．压力B．力矩C．温度D．厚度 2．属于传感器动态特性指标的是（D ） A．重复性B．线性度C．灵敏度D．固有频率 3．按照工作原理分类，固体图象式传感器属于（A ） A．光电式传感器B．电容式传感器 C．压电式传感器D．磁电式传感器 4．测量范围大的电容式位移传感器的类型为（ D ） A．变极板面积型B．变极距型 C．变介质型D．容栅型 5．利用相邻双臂桥检测的应变式传感器，为使其灵敏度高、非线性误差小（C ）A．两个桥臂都应当用大电阻值工作应变片 B．两个桥臂都应当用两个工作应变片串联 C．两个桥臂应当分别用应变量变化相反的工作应变片 D．两个桥臂应当分别用应变量变化相同的工作应变片 6．影响压电式加速度传感器低频响应能力的是（ D ） A．电缆的安装与固定方式B．电缆的长度 C．前置放大器的输出阻抗D．前置放大器的输入阻抗 7．固体半导体摄像元件CCD是一种（ C ） A．PN结光电二极管电路B．PNP型晶体管集成电路 C．MOS型晶体管开关集成电路D．NPN型晶体管集成电路 8．将电阻R和电容C串联后再并联到继电器或电源开关两端所构成的RC吸收电路，其作用是 （D ）A．抑制共模噪声B．抑制差模噪声 C．克服串扰D．消除电火花干扰 9．在采用限定最大偏差法进行数字滤波时，若限定偏差△Y≤0.01，本次采样值为0.315，上次采样值为0.301，则本次采样值Y n应选为（ A ） A．0.301 B．0.303 C．0.308 D．0.315 10．若模/数转换器输出二进制数的位数为10，最大输入信号为2.5V，则该转换器能分辨出的最小输入电压信号为（ D ） A．1.22mV B．2.44mV C．3.66mV D．4.88mV 11．周期信号的自相关函数必为（A ） A．周期偶函数B．非周期偶函数 C．周期奇函数D．非周期奇函数 12．已知函数x(t)的傅里叶变换为X（f），则函数y(t)=2x(3t)的傅里叶变换为（D ） A．2X(f 3) B．2 3 X(f 3 ) C．2 3 X(f) D．2X(f) 第二部分非选择题（共76分） 二、填空题（本大题共12小题，每小题1分，共12分）不写解答过程，将正确的答案写在每小题 的空格内。错填或不填均无分。 13．对传感器进行动态的主要目的是检测传感器的动态性能指标。 14．传感器的过载能力是指传感器在不致引起规定性能指标永久改变的条件下，允许超过的能力。 15．传感检测系统目前正迅速地由模拟式、数字式，向方向发展。 16．已知某传感器的灵敏度为K0，且灵敏度变化量为△K0，则该传感器的灵敏度误差计算公式为r s= 。

智能窗户控制系统软件说明

智能窗户控制系统软件V1.0设计说明 目录 前言 (1) 第一章软件总体设计 (1) 1.1. 软件需求概括 (1) 1.2. 定义 (1) 1.3. 功能概述 (1) 1.4. 总体结构和模块接口设计 (2) 第二章控制系统的总体设计 (3) 2.1. 功能设计 (3) 第三章软件控制系统的设计与实现 (5) 3.1. RF解码过程程序设计介绍 (5) 3.2. RF对码过程设计 (6) 3.3. 通信程序设计 (8) 3.4. IIC程序设计介绍 (9) 3.5. 接近开关程序设计 (12) 3.6. 震动开关检测程序设计 (13) 3.7. 墙面按键程序设计 (15) 第四章智能窗户控制系统的设计 (17) 第五章实测与结果说明 (18) 第六章结论 (18)

前言 目的 编写详细设计说明书是软件开发过程必不可少的部分，其目的是为了使开发人员在完成概要设计说明书的基础上完成概要设计规定的各项模块的具体实现的设计工作。 第一章软件总体设计 1.1.软件需求概括 本软件采用传统的软件开发生命周期的方法，采用自顶向下，逐步细化，模块化编程的软件设计方法。 本软件主要有以下几方面的功能 (1)RF遥控解码 (2)键盘扫描 (3)通信 (4)安全检测 (5)电机驱动 1.2.定义 本项目定义为智能遥控窗户系统软件。它将实现人机互动的无缝对接，实现智能关窗，遥控开关窗户，防雨报警等功能。 1.3.功能概述 1.墙体面板按键控制窗户的开/关 2.RF遥控器控制窗户的开/关 3.具有限位，童锁等检测功能 4.实时检测大气中的温湿度，下雨关窗 5.具有防盗，防夹手等安全性能的检测

螺纹通止规要求螺纹通规通

螺纹通止规要求螺纹通规通，止规止。 但是如果螺纹通规止，说明什么？ 螺纹止规通，又说明什么？ 我也来说两句查看全部回复 最新回复 ?wpc (2008-11-07 20:11:20) 在牙型正确的前提下螺纹通止规检测螺纹中径 ?lobont (2008-11-08 11:16:32) 对外螺纹而言，螺纹通规是做到中径上偏差，所以能通过就表示产品合格，通不过就表示螺纹做大了，要再修一刀； 螺纹止规做到中径下偏差，所以只能通过2～3牙，如果也通过，就表示外螺纹做小了，产品成为废品 ?qubin8512 (2008-11-18 15:36:05) 螺纹赛规与螺纹环规主要测量螺纹的中径。 ?datafield (2008-11-29 19:12:51) 检具不是万能的，只是方便而已。具体没什么的我有在哪本书上看过，是一本螺纹手册上的。 ?ZYC007 (2009-2-09 20:31:13) 在牙型正确的前提下螺纹通止规检测螺纹中径。 对外螺纹而言，但是如果螺纹通规止，说明螺纹中径大；螺纹止规通，又说明螺纹中径小。 ?WWCCJJ (2009-3-19 09:27:19) 检测的是螺纹的中径,螺纹检测规在检定时,也是检测其中径. ?tanjiren (2009-3-20 22:23:06) 螺纹通止规只能检测螺纹的作用中径,大径和底径等均无法准确测量出来. ?月夜(2009-4-01 21:47:13) 用来测量中径 ?丽萍(2009-4-02 10:11:41)

只能检测工件螺纹的中径 yg196733456 (2009-4-03 09:15:56)原来是测中径的知道了

感官动词的用法

感官动词 1.see, hear, listen to, watch, notice等词，后接宾语，再接省略to的动词不定式或ing形式。前者表全过程，后者表正在进行。句中有频率词时，以上的词也常跟动词原形。 注释:省略to的动词不定式--to do是动词不定式，省略了to,剩下do，其形式和动词原形是一样的，但说法不同。 see sb do sth 看到某人做了某事 see sb doing sth 看到某人在做某事 hear sb do sth 听到某人做了某事 hear sb doing sth 听到某人在做某事 以此类推... I heard someone knocking at the door when I fell asleep. (我入睡时有人正敲门,强调当时正在敲门) I heard someone knock at the door three times. (听到有人敲门的全过程) I often watch my classmates play volleyball after school. (此处有频率词often) （了解）若以上词用于被动语态，须将省略的to还原： see sb do sth----sb be seen to do sth hear sb do sth----sb be seen to do sth 以此类推... We saw him go into the restaurant. → He was seen to go into the restaurant. I hear the boy cry every day. → The boy is heard to cry every day. 2.感官动词look, sound, smell, taste, feel可当系动词，后接形容词。 He looks angry. His explanation sounds reasonable. The cakes smell nice.

传感与检测技术考试题

科目：《传感与检测技术》试题 考试说明：本课程为闭卷考试，答案一律答在后面得答题纸上，答在其它地方无效，可携带计算器。 一、选择题（每题1分，共10分，将答案写在答题纸上）。得分阅卷教师 1、下列被测物理量适合于使用红外传感器进行测量的是（） A．压力 B．力矩 C．温度 D．厚度 2、（）不可以改变电感式传感器的电容。 A、改变极板间距离 B、改变极板间电压 C、改变极板面积 D、改变介电常数 3、半导体应变片具有( )等优点。 A.灵敏度高 B.温度稳定性好 C.可靠性高 D.接口电路复杂 4、在下列元件中不属于光电元件的是（）。 A、光纤 B、光敏电阻 C、光电池 D、光敏晶体管 5、( )传感器可用于医疗上-50℃～150℃之间的温度测量。 A.金属辐射式 B.热电偶 C.半导体三极管 D.比色计 6、在信号远距离传输中，常采用调制方法，当高频振荡的频率受缓慢变化信号控制时，称为（）。 A、调频 B、调相 C、调幅 D、鉴相 7、改变电感传感器的引线电缆后，（）。 A.不必对整个仪器重新标定 B. 必须对整个仪器重新调零 C. 必须对整个仪器重新标定 D. 不必对整个仪器重新调零 8、若模/数转换器输出二进制数的位数为10，最大输入信号为2.5V，则该转换器能分辨出的最小输入电压信号为（）。 A．1.22mV B．2.44mV C．3.66mV D．4.88mV 9、在光的作用下，电子吸收光子能量从键合状态过渡到自由状态，引起物体电阻率的变化，

这种现象称为（ ）。 A.磁电效应 B.声光效应 C.光生伏特效应 D.光电导效应 10、属于传感器动态特性指标的是（ ） A ．重复性 B ．线性度 C ．灵敏度 D ．固有频率 二、填空题（每空1分，共20分，答案写在答题纸上）。 1、将温度转换为电势大小的热电式传感器是 传感器，而将温度变化转换为电阻大小的热电式传感器是 （金属材料）或 （半导体材料）。 2、热敏电阻可分为 和 型两大类。 3、电感式传感器也称为 传感器，它是利用 原理将被测的物理量转换成线圈 和 的变化，再由测量电路转换为电压或电流的变化，从而实现非电量到电量的转换。 4、霍尔效应是导体中的载流子在磁场中受 作用产生 的结果。 5、噪声一般可分为 和 两大类。 6、用于制作压电传感器的常用压电材料是 和 。 7、光纤是由折射率较大 和折射率较小 组成，按照的传播模式分类，光纤可以分为 光纤和 光纤。 8、传感检测系统目前正迅速地由模拟式、数字式，向 方向发展。 三、判断题：（每题1分，共7分，将答案写在答题纸上） 1、测量的输出值与理论输出值的差值即为测量误差。（ ） 2、接触式测温是基于热平衡原理进行的，非接触式测温是基于热辐射原理进行的（ ） 3、电涡流的产生必然消耗一部分磁场能量。（ ） 4、在光线作用下，电子从物体表面逸出的现象，称为外光电效应，也称光电发射效应。（ ） 5、在光线作用下，物体电导性能发生变化或产生一定方向的电动势的现象，称为内光电效应。（ ） 得分 阅卷教师 得分 阅卷教师

软件操作说明书

门禁考勤管理软件 使 用 说 明 书

软件使用基本步骤

一．系统介绍―――――――――――――――――――――――――――――2二．软件的安装――――――――――――――――――――――――――――2 三．基本信息设置―――――――――――――――――――――――――――2 １）部门班组设置―――――――――――――――――――――――――3 ２）人员资料管理―――――――――――――――――――――――――3 ３）数据库维护――――――――――――――――――――――――――3 ４）用户管理―――――――――――――――――――――――――――3 四．门禁管理―――――――――――――――――――――――――――――4 １）通迅端口设置―――――――――――――――――――――――――4２）控制器管理――――――――――――――――――――――――――4３）控制器设置――――――――――――――――――――――――――6４）卡片资料管理―――――――――――――――――――――――――11 ５）卡片领用注册―――――――――――――――――――――――――12６）实时监控―――――――――――――――――――――――――――13 五．数据采集与事件查询――――――――――――――――――――――――13 六．考勤管理―――――――――――――――――――――――――――――14 1）班次信息设置――――――――――――――――――――――――――14 2）考勤参数设置――――――――――――――――――――――――――15 3）考勤排班――――――――――――――――――――――――――――15 4）节假日登记―――――――――――――――――――――――――――16 5）调休日期登记――――――――――――――――――――――――――16 6）请假/待料登记―――――――――――――――――――――――――17 7）原始数据修改――――――――――――――――――――――――――17 8）考勤数据处理分析――――――――――――――――――――――――17 9）考勤数据汇总―――――――—――――――――――――――――――18 10）考勤明细表—―――――――――――――――――――――――――18 11）考勤汇总表――――――――――――――――――――――――――18 12）日打卡查询――――――――――――――――――――――――――18 13）补卡记录查询—――――――――――――――――――――――――19

NPT螺纹以及检测方法详解

N P T螺纹以及检测方法详 解 Prepared on 22 November 2020

一、目的：规范公司技术员，检验员，操作员对NPT螺纹的了解。 二、适用范围：适用于公司任何NPT螺纹类产品，参考资料为通用管螺 纹和国家标准GB/T12716-2011。 三、目录 1、NPT和NPTF介绍 2、螺纹技术参数参数讲解 3、NPT与NPTF加工工艺 4、NPT和NPTF的检测方法 四、内容： NPT和NPTF螺纹介绍 NPT 是 National (American) Pipe Thread 的缩写，属於美国标准的 60 度锥管 密封螺纹，用於北美地区，美国标准为13)通用管螺纹．国家标准可查阅 GB/T12716-2011。NPTF：美制干密封圆锥管螺。NPTF = National Pipe Thread Fine 称之为一般用途的锥管螺纹，这也是我们以前称之为的布氏锥螺纹。NPTF 螺纹称之为干密封式锥管螺纹，它连接密封的原理是在没有润滑剂或密封填 料情况下完全依靠螺纹自身形成密封，设计意图是使内、外螺纹牙的侧面、 牙顶和牙底同时接触，来达到密封的目的。它们两者的牙型角、斜度等指标 都是相同的，关键是牙顶和牙底的削平高度不一样，所以，量规的设计也是 不一样的。NPTF干密封管螺纹的牙形精度比NPT螺纹高，旋合时不用任何 填料，完全依靠螺纹自身形成密封，螺纹间无任何密封介质。干密封管螺纹 规定有较为严格的公差，属精密型螺纹，仅用在特殊场合。这种螺纹有较高 的强度和良好的密封性，在具有薄截面的脆硬材料上采用此螺纹可以减少断 裂现象。NPTF内、外螺纹牙顶与牙底间没有间隙，是过盈配合，而NPT螺 纹是过渡配合。NPTF螺纹主要用于高温高压对密封要求严格的场所。NPT

英语中感官动词的用法

英语中感官动词的用法 一、感官动词 1、感官动词(及物动词)有：see/notice/look at/watch/observe/listen to/hear/feel(Vt)/taste(Vt)/smell(Vt) 2、连缀动词(含感官不及物动词) be/get/become/feel/look/sound/smell/taste/keep/stay/seem/ appear/grow/turn/prove/remain/go/run 二、具体用法： 1、see, hear, smell, taste, feel,这五个动词均可作连系动词，后面接形容词作表语，说明主语所处的状态。其意思分别为"看/听/闻/尝/摸起来……"。除look之外，其它几个动词的主语往往是物，而不是人。 例如：These flowers smell very sweet.这些花闻起来很香。 The tomatoes feel very soft.这些西红柿摸起来很软。 2、这些动词后面也可接介词like短语，like后面常用名词。 例如：Her idea sounds like fun.她的主意听起来很有趣。 3、这五个感官动词也可作实义动词,除look(当"看起来……"讲时)只能作不及物动词外,其余四个既可作及物动词也可作不及物动词,此时作为实义动词讲时其主语一般为人。 例如:She smelt the meat.她闻了闻那块肉。 I felt in my pocket for cigarettes.我用手在口袋里摸香烟。 4、taste, smell作不及物动词时,可用于"t aste / smell + of +名词"结构,意为"有……味道/气味"。 例如:The air in the room smells of earth.房间里的空气有股泥土味。 5、它们(sound除外)可以直接作名词,与have或take构成短语。 例如：May I have a taste of the mooncakes?我可以尝一口这月饼吗？taste有品位、味道的意思。 例如：I don’t like the taste of the garlic.我不喜欢大蒜的味道。 She dresses in poor taste.她穿着没有品位。 look有外观，特色的意思，例：The place has a European look.此地具有欧洲特色。 feel有感觉，感受的意思，watch有手表，观察的意思。例：My watch is expensive.我的手表很贵。 6、其中look, sound, feel还能构成"look / sound / feel + as if +从句"结构，意为"看起来/听起来/感觉好像……"。 例如：It looks as if our class is going to win.看来我们班好像要获胜了。 7、感官动词+do与+doing的区别： see, watch, observe, notice, look at, hear, listen to, smell, taste, feel + do表示动作的完整性，真实性；+doing 表示动作的连续性，进行性。 I saw him work in the garden yesterday.昨天我看见他在花园里干活了。(强调"我看见了"

测试与传感器技术试题库及答案

测试与传感器技术试题(1) 一、判断题(判断下列各题，正确的在题干后面的括号内打A“√”，错误的打B“×”。每小 题2分，共10分) 1.X-Y记录仪可记录任何频率的信号。( B ) 2.分析周期信号的频谱的工具是傅立叶级数。( A ) 3.阻抗变换器的作用是将传感器的高输出阻抗变为低阻抗输出。( A ) 4.瞬态信号的频谱一定是连续的。( A ) 5.系统的不失真测试条件要求测试系统的幅频特性和相频特性均保持恒定。( B ) 二、单项选择题(在每小题的四个备选答案中选出一个正确答案，并将其号码填在题干的括号 内。每小题2分，共10分) 1.信号x(t)=sin(2t+1)+cos(t/3)是( A ) A.周期信号 B.非周期信号 C.瞬态信号 D.随机信号 *2.用共振法确定系统的固有频率时，在有阻尼条件下，( )频率与系统固有频率一致。 A.加速度共振 B.速度共振 C.位移共振 D.自由振动 3.压电式加速度计与测振仪之间可以串接的是( A ) A.电荷放大器 B.A/D转换器 C.相敏检波器 D.滤波器 4.温度误差的线路补偿法是利用电桥( C )实现的。 A.相邻桥臂同变输入电压相加 B.相邻桥臂差变输入电压相减 C.相对桥臂同变输入电压相加 D.相对桥臂差变输入电压相加 5.差动变压器式位移传感器中线圈之间的互感M( B ) A.始终保持不变 B.随被测位移的变化而变化 C.不随被测位移的变化而变化 D.随线圈电流的变化而变化 三、填空题(每空1分，共30分) 1.若位移信号x(t)=Acos(ωt+ψ),则其速度信号的振幅为___AW_____，加速度信号的振幅为 ______AW2__。 2.利用数字频率计测量振动频率时，一般对低频信号测________，高频信号测________。 3.信号的频谱函数可表示为__幅值______频谱和___相位_____频谱。 4.用共振法确定系统的固有频率时，由于测量的振动参数不同，存在着________共振频率， ________共振频率，________共振频率。 5.高频情况下，多采用___压电式____测力传感器来测量激振力，而且在实验前需对测力系统 进行____标定____。 6.当压电式加速度计固定在试件上而承受振动时，质量块产生一可变力作用在压电晶片上， 由于___压电_____效应，在压电晶片两表面上就有___电荷_____产生。 7.阻抗头由两部分组成，一部分是___力_____传感器，一部分是_加速度_______传感器。它 是用来测量驱动点__阻抗______的。 8.阻容式积分电路中，输出电压从_电容C_______两端取出，RC称为__积分______时间常数， RC值越大，积分结果越__准确______，但输出信号___越小_____。 9.光线示波器的关键部件是________，通过它，可将按一定规律变化的________信号，转换 成按同样规律变化的________摆动信号，从而记录测量结果。 10.热电偶的热电势由________和________两部分组成。 @@@11.测试装置所能检测到的输入信号的最小变化量称为_分辨率_______。 12.具有质量为M，刚度为K的振动体的固有频率为________。

控制系统使用说明

控制系统使用说明 系统针对轴流风机而设计的控制系统, 系统分为上位监视及下位控制两部分 本操作为上位监控软件的使用说明: 1: 启动计算机: 按下计算机电源开关约2秒, 计算机启动指示灯点亮, 稍过大约20秒钟屏幕出现操作系统选择菜单, 通过键盘的“↑↓”键选择“windows NT 4.0”菜单，这时系统进入WINDOWS NT 4.0操作系统，进入系统的操作画面。 2：系统操作 系统共分：开机画面、停机画面、趋势画面、报警画面、主机流程画面、轴系监测画面、润滑油站画面、动力油站画面、运行工况画面、运行记录画面等十幅画面，下面就十幅画面的作用及操作进行说明 A、开机画面： 开机： 当风机开始运转前，需对各项条件进行检查，在本画面中主要对如下指标进行检查，红色为有效： 1、静叶关闭：静叶角度在14度

2、放空阀全开：放空阀指示为0% 3、润滑油压正常 4、润滑油温正常 5、动力油压正常 6、逆止阀全关 7、存储器复位：按下存储器复位按钮，即可复位，若复位不成 需查看停机画面。 8、试验开关复位：按下试验开关按钮即可，试验开关按钮在风 机启动后，将自动消失，同时试验开关也自动复位。 当以上条件达到时，按下“允许机组启动”按钮，这时机组允许启动指示变为红色，PLC机柜里的“1KA”继电器将导通。机组允许启动信号传到高压柜，等待电机启动。开始进行高压合闸操作，主电机运转，主电机运转稳定后，屏幕上主电机运行指示变红。这时静叶释放按钮变红，按下静叶释放按钮后，静叶从14度开到22度，静叶释放成功指示变红。 应继续观察风机已平稳运行后，按下自动操作按钮，启机过程结束。 B、停机画面： 停机是指极有可能对风机产生巨大危害的下列条件成立时，PLC 会让电机停止运转： 1、风机轴位移过大

通止规的用法及管理

通止规的用法及管理 1、止规 使用前：应经相关检验计量机构检验计量合格后，方可投入生产现场使用。 使用时：应注意被测螺纹公差等级及偏差代号与环规标识公差等级、偏差代号相同（如M24*1.5-6h与M24*1.5-5g两种环规外形相同，其螺纹公差带不相同，错用后将产生批量不合格品)。 检验测量过程：首先要清理干净被测螺纹油污及杂质，然后在环规与被测螺纹对正后，用大母指与食指转动环规，旋入螺纹长度在2个螺距之内为合格，否则判为不合格品。 2、通规 使用前：应经相关检验计量机构检验计量合格后，方可投入生产现场使用。 使用时：应注意被测螺纹公差等级及偏差代号与环规标识的公差等级、偏差代号相同（如M24*1.5-6h与M24*1.5-5g两种环规外形相同，其螺纹公差带不相同，错用后将产生批量不合格品)。 检验测量过程：首先要清理干净被测螺纹塞规油污及杂质，然后在环规与被测螺纹对正后，用大母指与食指转动环规，使其在自由状态下旋合通过螺纹全部长度判定合格，否则以不通判定。 3、注意事项 在用量具应在每个工作日用校对塞规计量一次。经校对塞规计量超差或者达到计量器具周检期限的环规，由计量管理人员收回、标识隔离并作相应的处理措施。 可调节螺纹环规经调整后，测量部位会产生失圆，此现象由计量修复人员经螺纹磨削加工后再次计量鉴定，各尺寸合格后方可投入使用。 报废环规应标识隔离并及时处理，不得流入生产现场。 4、维护与保养 量具（环规）使用完毕后，应及时清理干净测量部位附着物，存放在规定的量具盒内。生产现场在用量具应摆放在工艺定置位置，轻拿轻放，以防止磕碰而损坏测量表面。 严禁将量具作为切削工具强制旋入螺纹，避免造成早期磨损。可调节螺纹环规严禁非计量工作人员随意调整，确保量具的准确性。环规长时间不用，应交计量管理部门妥善保管。

感官动词的用法

1.感官动词用法之一：see, hear, listen to, watch, notice等词，后接宾语，再接动词原形或ing形式。前者表全过程，后者表正在进行。句中有频率词时，以上的词也常跟动词原形。 I heard someone knocking at the door when I fell asleep. (我入睡时有人正敲门) I heard someone knock at the door three times. (听的是全过程) I often watch my classmates play volleyball after school.(此处有频率词often) 若以上词用于被动语态，后面原有动词原形改为带to不定式： We saw him go into the restaurant. →He was seen to go into the restaurant. I hear the boy cry every day. →The boy is heard to cry every day. 2.感官动词用法之二：look, sound, smell, taste, feel可当系动词，后接形容词： He looks angry. It sounds good. The flowers smell beautiful. The sweets taste sweet. The silk feels soft. I felt tired. They all looked tired. 这些动词都不用于被动语态。如：The sweets are tasted sweet.是个病句。注意：如果加介词like,则后不可接形容词，而接名词或代词：

工程测试技术试题及答案

工程测试技术试题及答案

1.

2.对于一阶传感器系统，当其时间常数（或τ） 越小，其频率响应特性越好。 3.激波管标定系统中，激波管的作用是一种动态 标定设备，能产生阶跃压力信号输出。 4.金属电阻应变片的规格一般以面积（或长× 宽）和初始阻值表示。 5.用电阻应变片测量构件的变形，影响电阻应变 片电阻变化的因素有：应变片的灵敏度和初始阻值、被测构件的应变量、以及应变片沿构件的粘贴方向。（因为：△R=KεR，K为灵敏度，R为应变片初始阻值，ε被测构件的应变量） 6.将电阻丝绕成应变片后，由于存在横向效应， 其灵敏系数一般会减小。 7.在电桥测量中，由于电桥接法不同，输出电 压的灵敏度也不同，全桥接法可以得到最大灵敏度输出。 8.应变片的温度误差补偿方法通常可分为：桥 路补偿法、应变片自补偿法。

9.根据工作原理，变气隙型自感式传感器的灵 敏度具有理论上的非线性。 10.电涡流接近开关结构简单，根据其工作原 理，不可用来进行类似如玻璃瓶、塑料零件以及水的液位的检测。 11.在差动式自感传感器中，若采用交流桥路为 变换电路，常出现零点残余电压现象，该现象使传感器灵敏度下降，灵敏阈值增大，非线性误差增大。 12.差动变压器式位移传感器是将被测位移量 的变化转换成线圈互感系数的变化，两个次级线圈要求反向串接。 13.电容传感器的转换电路包括：交流电桥、变 压器电桥、调频电路、运算放大器电路。14.压电式传感器是一种可逆型传感器，即可将 机械能转换为电能。也可反之实现逆向变换。 15.压电传感器中压电晶片的等效电路，可以看 作是一个电荷源与一个电容器的并联。 16.压电传感器测量电路常接电压或电荷放大

威利普LEDESC控制系统操作说明书

LED-ECS编辑控制系统V5.2 用 户 手 册 目录 第一章概述 (3) 1.1LED-ECS编辑控制系统介绍 (3) 1.2运行环境 (3) 第二章安装卸载 (3) 2.1安装 (3) 2.2卸载 (5) 第三章软件介绍 (5) 3.1界面介绍 (5) 3.2操作流程介绍 (13) 3.3基本概念介绍 (21) 第四章其他功能 (25) 4.1区域对齐工具栏 (25) 4.2节目对象复制、粘贴 (26) 4.3亮度调整 (26) 第五章发送 (27) 5.1发送数据 (27) 第六章常见问题解决 (28) 6.1计算机和控制卡通讯不上 (28) 6.2显示屏区域反色或亮度不够 (29)

6.3显示屏出现拖尾现象，显示屏的后面出现闪烁不稳定 (29) 6.4注意事项 (31) 6.5显示屏花屏 (31) 6.6错列现象 (32) 6.7杂点现象 (32) 第一章概述 1.1LED-ECS编辑控制系统介绍 LED-ECS编辑控制系统，是一款专门用于LED图文控制卡的配套软件。其具有功能齐全，界面直观，操作简单、方便等优点。自发布以来，受到了广大用户的一致好评。 1.2运行环境 ?操作系统 中英文Windows/2000/NT/XP ?硬件配置 CPU:奔腾600MHz以上 内存:128M 第二章安装卸载 2.1LED-ECS编辑控制系统》软件安装很简单，操作如下：双击“LED-ECS编辑控制系统”安装程序，即可弹出安装界面，如图2-1开始安装。如图所示 图2-1 单击“下一步”进入选择安装路径界面，如图2-2，如果对此不了解使用默认安装路径即可 图2-2 图2-3 单击“完成”，完成安装过程。 2.2软件卸载如图2-2 《LED-ECS编辑控制系统V5.2》提供了自动卸载功能，使您可以方便的删除《LED-ECS编辑控制系统V5.2》的所有文件、程序组件和快捷方式。用户可以在“LED-ECS编辑控制系统V5.2”组中选择“卸载LED-ECS编辑控制系统V5.2”卸载程序。也可以在“控制面板”中选择“添加/删除程序”快速卸载。卸载程序界面如图2-4，此时选择自动选项即可卸载所有文件、程序组和快捷方式。 图2-4 第三章、软件介绍

工程测试技术试题及答案

复习总结 一、概念题 1.测试过程中，若所测试的信号不随时间变化或变化非常缓慢，称这种测试称为 静态测试。如果所测试的信号随时间周期变化或变化很快，这种测试称为动态测试。 2.传感器是把被测量转换成易于变换、传输和处理的一种器件或装置。 3.按构成原理分类，电阻应变片、热敏电阻、压电晶片属物性型传感器。 4.按构成原理分类，电容传感器、自感型电感式传感器属结构型传感器。 5.为提高和改善传感器的技术性能，可采取以下技术措施：差动技术、平均技术 以及补偿与修正技术。 6.传感器的定度曲线（或标定曲线）与拟合直线之间的偏离程度称为传感器的线 性度。 7.传感器的灵敏度是指稳态时，输出变化量与输入变化量之间的比值。 8.对于一阶传感器系统，当其时间常数（或τ）越小，其频率响应特性越好。 9.激波管标定系统中，激波管的作用是一种动态标定设备，能产生阶跃压力信号 输出。 10.金属电阻应变片的规格一般以面积（或长×宽）和初始阻值表示。 11.用电阻应变片测量构件的变形，影响电阻应变片电阻变化的因素有：应变片的 灵敏度和初始阻值、被测构件的应变量、以及应变片沿构件的粘贴方向。（因为：△R=KεR，K为灵敏度，R为应变片初始阻值，ε被测构件的应变量） 12.将电阻丝绕成应变片后，由于存在横向效应，其灵敏系数一般会减小。 13.在电桥测量中，由于电桥接法不同，输出电压的灵敏度也不同，全桥接法可以 得到最大灵敏度输出。 14.应变片的温度误差补偿方法通常可分为：桥路补偿法、应变片自补偿法。 15.根据工作原理，变气隙型自感式传感器的灵敏度具有理论上的非线性。 16.电涡流接近开关结构简单，根据其工作原理，不可用来进行类似如玻璃瓶、塑 料零件以及水的液位的检测。