Line bisectors and radial velocity jitter from SARG spectra
a r X i v :a s t r o -p h /0508096v 1 3 A u g 2005
Astronomy &Astrophysics manuscript no.2888February 5,2008
(DOI:will be inserted by hand later)
Line bisectors and radial velocity jitter from SARG spectra ?
A.F.Mart′?nez Fiorenzano 1,2,R.G.Gratton 2,S.Desidera 2,R.Cosentino 3,4,and M.Endl 5
1Dipartimento di Astronomia Universit`a di Padova,Vicolo dell’Osservatorio 2,I-35122,Padova,Italy 2INAF -Osservatorio Astronomico di Padova,Vicolo dell’Osservatorio 5,I-35122,Padova,Italy 3INAF -Osservatorio Astro?sico di Catania,Via S.So?a 78,Catania,Italy
4INAF -Centro Galileo Galilei,Calle Alvarez de Abreu 70,38700Santa Cruz de La Palma (TF),Spain 5
McDonald Observatory,The University of Texas at Austin,Austin,TX 78712,USA
Received ;accepted
Abstract.
We present an analysis of spectral line bisector variations for a few stars observed in the SARG high precision radial velocity planet survey,and discuss their relationship with di ?erential radial velocities.The spectra we consider are the same used for determining radial velocities.The iodine cell lines employed in the measurement of radial velocities were removed before bisector analysis.The line bisectors were then computed from average absorption pro?les obtained by cross correlation of the stellar spectra with a mask made from suitable lines of a solar catalog.Bisector velocity spans were then determined:errors in these quantities compare well with theoretical expectations based on resolution,S /N and line shape.The plot of bisector velocity span against radial velocity was studied to search for correlations between line asymmetries and radial velocity variations.A correlation was seen for HD 166435due to stellar activity,and for HD 8071B due to spectral contamination by the companion.No correlation was seen for 51Peg and ρCrB,stars hosting planets.We conclude that this technique may be useful to separate radial velocity variations due to barycenter motion from spurious signals in spectra acquired with the iodine cell.
Key words.stars:atmospheres –stars:activity –stars:planetary systems –techniques:spectroscopic –techniques:radial
velocities –line:pro?les
1.Introduction
The study of activity jitter is mandatory in the search for exoplanets using the radial velocity (RV)technique,because it represents an important source of noise and a proper analysis is necessary to discard false alarms (e.g.,HD 166435:Queloz et al.2001;HD 219542B:Desidera et al.2003,2004a).The di ?erential RV variations induced by stellar activity are due to changes in the pro?le of spectral lines caused by the presence of spots and /or the alteration of the granulation pattern in active regions (Saar &Donahue 1997,Hatzes 2002,Saar 2003and K¨u rster et al.2003).The activity jitter of a star may be predicted by means of statistical relations from its chromospheric emission,rotational velocity or amplitude of photometric variations (Saar et al.1998and Paulson et al.2004).Simultaneous determination of RV ,chromospheric emission and /or photometry is even more powerful in disen-
2 A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG spectra 2005).In addition,asymmetries of spectral lines may arise due
to contamination of the spectrum by a nearby star.This point
is of particular relevance for the targets we are studying in the
SARG survey(Desidera et al.2004b),because by design all of
them are visual binaries.In this case a companion near the line
of sight may contaminate the spectral features of the star being
observed.Finally,spurious line pro?le asymmetries may be
due to instrumental causes,e.g.,non symmetric illumination
of the slit.
Line bisector variations may be studied quite easily in spectra
acquired using?bers(see e.g.,Queloz et al.2001).The?bers
provide a constant,roughly symmetric illumination of the slit.
Furthermore,spectra are generally acquired with simultaneous
wavelength calibration lamps,rather than imprinting absorp-tion cell features on the stellar spectral lines.No attempt has been made to our knowledge to study line bisectors on spectra obtained through an iodine cell.One disadvantage is the necessity to remove the iodine lines from the stellar spectra; but on the other hand,the iodine lines allow a?ne wavelength calibration and the possibility of monitoring the instrumental pro?le.
In this paper we present such an attempt;line bisectors and radial velocities are determined for SARG stellar spectra, to study possible trends between spectral line shapes(line bisectors)and RVs.
This paper describes the procedure followed to handle the spectra,to remove iodine lines,the construction of a mask made from selected lines of a solar catalogue,the cross correlation function(CCF)computed between mask and stellar spectra,the determination of the line bisector and the calculation of the bisector velocity span.We present results obtained for?ve stars:we found a clear correlation between the line bisector velocity span and RV for HD166435,likely due to stellar activity,consistent with previous published work by Queloz et al.(2001).A similar correlation was found for HD8071B due to contamination by light from the companion. We did not?nd any correlation for stars known to host planets like51Peg andρCrB,and the false alarm(inconclusive)case of HD219542B.
In the next section we describe some aspects of the obser-vations;Section3explains the procedure employed in the analysis with results presented in Section4.The last two sections are devoted to a discussion of the error analysis and conclusions.
2.Observations and data reduction
The data discussed in the present paper are part of the RV survey aimed to?nd planets around stars in wide binaries (Desidera et al.2004b),ongoing at TNG using the high resolution spectrograph SARG(Gratton et al.2001).The spectra have a resolution of R～150000,covering the spectral range4580?-7900?in55echelle orders,with S/N values in the range70-400and were taken from September2000 until August2004.Slit width was set at0.27′′,much smaller than the typical seeing Full Width Half Maximum(FWHM). Furthermore,an autoguider system,viewing the slit by
means Fig.1.Portion of a spectrum from HD166435.The top spec-trum corresponds to the program star with iodine lines,in the middle is the spectrum of the B-star with iodine lines and on the bottom is the program star spectrum after the division by the B-star spectrum.The division was computed for the whole order:the poor result is due to errors in the wavelength cali-bration along one order.In this case the Iodine lines are better removed in the left half than in the right half of the order.
of a detector with its wavelength response peaked at the wavelength of the iodine cell lines,was employed,keeping the instrumental pro?le stable and fairly independent of illumination e?ects.Guiding was generally done using the image of the binary companion on the slit viewer.
Data reduction was performed in a standard way using IRAF1. High precision RVs were measured on these spectra with the AUSTRAL code(Endl et al.2000)as described in Desidera et al.(2003).
The iodine cell technique includes the acquisition of spectra from a featureless source(a fast rotating B-star or the?at?eld lamp)taken with the iodine cell inserted in the optical path (Butler et al.1996).This kind of spectra is necessary only for the deconvolution of stellar templates(taken without the cell), but they were acquired also in most of the observing nights of our survey to monitor instrument performances.These featureless source spectra were used to remove the Iodine lines from the science spectra,as explained in the next section.
3.Data analysis
3.1.Handling of the spectra
The iodine lines,superimposed on the stellar spectrum for wavelength calibration and RV determination,were eliminated because the line bisector is intended to study the asymmetries of the stellar spectral lines alone.For this task,spectra of fast rotating(V sin i≥200km s?1)B-stars were employed.The analysis was made only for the wavelength range where the
A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG spectra
3 Fig.2.An order of a spectrum of HD166435(wavelength
range6039??6107?)shown in Figure1.The order has been
divided into7chunks,as described in the text.The spectra are
shifted arbitrarily in?ux to show:on top the stellar spectra with
iodine lines,in the middle the B-star spectra(adjusted to the
wavelength o?set)with the iodine lines and on the bottom the
clean stellar spectra after dividing the program star spectrum
by the B-star spectrum.
iodine lines appear in the spectra(5036?-6108?)along21
orders.We used only this spectral region because there the
wavelength calibration is more accurate,because of the iodine
lines themselves.
To handle the spectra,each order was divided in7pieces of
500spectral points each,corresponding to a wavelength width
of～10?,overlapped by60points(～1?)to eventually
recover any absorption lying at the edges of the chunks.This
procedure of cutting the spectra in pieces was clearly advan-
tageous,while the division of complete orders displayed not
optimal results,related to errors in the wavelength calibration
of the spectra(see Figure1).A cross correlation computed
between the spectral chunks of the B-star and the program star
determined the o?set in wavelength between the iodine lines
common to both spectra.The B-star spectrum was adjusted
using a Hermite spline interpolation(INTEP,see Hill1982)
to the wavelength scale de?ned by the program star spectrum
after application of the appropriate o?set and?nally divided to
the program star spectrum(see Figure2;details will appear
elsewhere:Mart′?nez Fiorenzano2005).The success of this
procedure depends on the stability of the instrumental pro?le
over time,since the B-star spectra were usually acquired at the
beginning or the end of each night.
In a few cases,the cross correlation procedure used to de-
termine the wavelength o?set of chunks did not provide a
reasonable value;in these cases the division of the star?ux
by the B-star?ux added noise rather than removing the iodine
lines.These noisy chunks were rejected from further analysis.
Spikes due to cosmic rays or hot pixels were removed by
replacing the spectral values within them with the averaged
?ux of adjacent spectral points.This procedure was only
applied to those cases where spikes occurred far from the line
centers.In the very rare cases where the spikes occurred near
the centers of the lines used in our analysis,possibly a?ecting
the line bisector analysis described below,the relevant chunks
were simply removed from further analysis,from all spectra of
the same star.
3.2.The cross correlation function(CCF)
3.2.1.The solar catalogue and line selection for the
mask
The list of spectral lines by Moore et al.(1966)was used to
prepare the spectral mask needed for the computation of the
CCF.A preliminary line list was obtained by selecting those
lines that do not have possible contaminants(wavelength
separation 0.1?),and have reduced width between3and
30F.F(Fraunhofer)is de?ned as the dimensionless quantity
?λ/λ×106,where?λis the equivalent width(see Moore et al.
1966).The range of reduced width chosen here corresponds to
a range of central line depths from0.14to0.75in continuum
units(in the solar spectrum).The CCFs we derived thus
represent average pro?le for lines of intermediate strength.
Once a preliminary list of lines was determined for the wave-
length range of interest(5036?to6108?),a further selection
was made by inspecting the“The Sacramento Peak Atlas of
the Solar Flux Spectrum”(Beckers et al.1976).Lines were
labeled according to their appearance:“y”(very good):sharp,
clear,with weak wings;“y:”(good):clear but near other lines
altering their wings;“?”(not very good):with small blends or
strong wings.Many other lines,blended or too close to other
spectral lines,were removed from the list at this step.
The mask used to compute the CCF is a sum ofδ-function
pro?les corresponding to1for the line wavelength,with a base
of two(spectral)points,and0elsewhere.The extensive line
list(including very good,good and not very good lines:a
total of about300lines)served to determine the RV;this gave
the centroid value of the average absorption pro?le obtained
by the CCF.Once this point was established,which helps to
properly locate the pro?les for the addition,a new computation
of the CCF was performed only with the very good lines to
obtain an improved average pro?le,used to calculate reliable
4 A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG
spectra
Fig.3.An order of a spectrum of HD 166435.The left column shows individual chunks of the spectrum (blue lines),after re-moval of the iodine cell lines (see Figure 1).Overimposed (as red lines)is the mask used for the determination of the CCF (only lines classi?ed as very good are shown here).It is made of a sum of δ?functions centered on the rest wavelengths of the selected lines.Note the wavelength shifts between the stel-lar lines and the mask peaks due to the non-zero radial velocity of the star.The CCF for individual chunks computed by cross-correlating the spectra with the masks given on the left panels are shown in the right panels.The dashed line,shifted slightly below the pro?les for clarity,represent the Gaussian ?t com-puted to determine the local minimum of the CCF for each chunk.There are no CCF pro?les for chunks 1,4and 7due to the lack of suitable lines for the mask in these wavelength
average line bisectors (see Figure 3).
3.2.2.The cross correlation and addition of pro?les
A cross correlation between the mask and the stellar spectrum
was computed for each chunk;the addition of all these cross correlations gave the average pro?le.Due to the relatively low S /N of some spectra,use of the average of many lines is appropriate for this study (the variations of line bisectors with time).On the other hand,the actual line bisector depends on the line depth,so that our “average”line bisector does not rigorously correspond to the line bisector of a line with similar depth of the CCF.Therefore,the use of our average pro?le would be misleading for some scienti?c goals such as the study of convection in stellar atmospheres.
Due to di ?erent illumination of the CCD,each chunk along an order has di ?erent ?ux values,those close to the center of the orders being more luminous and yielding then results of higher S /N.To account for this,before summing the individual cross correlations,each of them was multiplied by an appropriate weight,proportional to the instrumental ?ux at the center of the chunk.
Once adjusted to a common reference frame,which may be thought of as a centering procedure,and multiplied by its weight,all CCF pro?les were added to get the ?nal pro?le for the spectrum.This was normalized to determine the ?nally adopted average line pro?les using the reference continuum determined in the IRAF reduction.This was obtained by interpolating a polynome throughout the spectra with a suitable clipping rejection procedure.Note that this reference continuum may contain signi?cant errors,so that there may be points in the normalized CCFs that are well above unity.However,we kept our procedures strictly uniform throughout the analysis of di ?erent spectra;we then expect that these errors in the location of the reference continuum mainly a ?ect absolute pro?les and bisector estimates,but only marginally their spectrum-to-spectrum variations,which are of interest for the present discussion.
3.3.The line bisector calculation
The bisector of an absorption line is the middle point of the horizontal segment connecting points on the left and right sides of the pro?le with the same ?ux level.The line bisector is obtained by combining bisector points ranging from the core toward the wings of the line.
For the bisector determination,it is necessary to adjust the ordinate axis of the pro?le to a convenient scale and to determine the values in velocity belonging to the left and right points for a given ?ux value.This is accomplished by interpolating (using INTEP,see Hill 1982)the absorption pro?le to the desired scale (details will appear in Mart′?nez Fiorenzano 2005).
A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG spectra
5 Fig.4.Spectrum of HD166435.In the top panel we show the
normalized cross correlation pro?le,the line bisector,the top
and bottom zones(both with?F=0.02;?F=top f?top i=
bot f?bot i).In the bottom panel we show a zoom of the pro?le
with the RV scale increased to better display the asymmetries
of the line bisector.
3.4.The bisector velocity span
To quantify the asymmetry of the spectral lines and look
for correlation with RV it is useful to introduce the bisector
velocity span(Toner&Gray1988).This is determined by
considering a top zone near the wings and a bottom zone close
to the core of the lines,which represent interesting regions to
study the velocity given by the bisector(see Figure4).The
di?erence of the average values of velocities in the top and
bottom zones,V T and V B respectively,determine the bisector
velocity span(BVS for short).
The location of the top and bottom zones,as well as their width
?F,were determined as percentages along the absorption pro-
?les.They were de?ned using as templates the spectra of HD
166435;the same zones were then employed in the study of
the other objects to be consistent in the analysis procedure.
The Spearman nonparametric rank correlation coe?cient was
computed to establish the signi?cance of the linear correlation
between BVS and RV for each star.
3.5.Error determination
The expression given by Gray(1983)for the bisector error due
to photometric error was employed to establish the error for
the bisector velocity span.The photon noise error,determined
for the speci?c case of SARG using Gray’s equation,yields the
expression:
δV= S x dF
6 A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG
spectra
Fig.5.Instrumental pro?le (IP)analysis.Top Panel:plot of IP
BVS vs.RVs of HD 166435.Bottom panel:plot of IP BVS vs.BVS of HD 166435.No evidence of trends were found.between RV and line bisector orientation (Queloz et al.2001).The large amplitude of the activity-induced variations and their stability make this star an ideal target to test new procedures like those presented in this paper.
Twelve spectra of HD 166435were acquired between May 2003and May 2004.The line bisectors,derived from the spec-tra,were used to study the correlation between the BVS and the RVs.The plot of BVS against RV ((V T ?V B )vs .V r )was ?tted to a straight line.
In principle,the location and extension of top and bottom zones of the line pro?les used in the derivation of the BVS are arbi-trary.In order to optimize detection of variations of the BVS correlated with RV variations,we maximized the m /σratio (where m is the slope of the straight line ?tting of BVS against RV ,and σits uncertainty)over di ?erent choices of the loca-tion and amplitude of the line pro?le regions used to derive the BVS.The m /σratio is an indicator of the signi?cance of the linear term in the straight line ?tting.
The top and bottom zones were determined according to the relative absorption percentages in which the highest signi?-cance was found:top centered at 25%of the maximum
absorp-
Fig.6.Upper panel:plot of BVS vs.RV for HD 166435and the best ?t to a straight line.Lower panel:line bisectors for individual spectra adjusted to their corresponding RV .The hor-izontal lines enclose the top and bottom zones considered for the ?tting analysis.
Table 1.Bisector velocity span from spectra of HD 166435.53lines were employed in the mask for the CCF.
2775.65?231.1±56.490.6±5.81642776.68154.1±57.8?127.9±6.61562809.62?216.4±51.855.1±8.21782818.62173.8±109.3?104.4±13.4862860.40220.3±92.8?83.8±7.7982861.42110.8±117.132.3±10.6812862.42?358.8±64.5124.9±6.61402891.37172.0±68.1?76.5±7.21382892.35?239.4±72.5134.0±8.41263129.74113.1±60.8?99.0±7.41493130.7376.3±45.9?16.1±6.12013131.74?132.2±57.070.9±6.0164
A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG spectra
7
Fig.7.Upper panel:plot of BVS vs.RV for HD 8071B and the best ?t to a straight line.The dotted line corresponds to the best ?t discarding the spectrum with higher RV .Lower panel:line bisectors for individual spectra adjusted to their corresponding RV .The horizontal lines enclose the top and bottom zones con-sidered in the ?tting analysis.
tion,bottom at 87%;in both cases the width ?F was of 25%.For consistency,these percentage values were then considered for the analysis of all the stars.
The upper panel of Figure 6displays the plot of BVS against RV;superimposed is the best ?tting straight line,with:(V T ?V B )=(?1.98±0.21)×V r +(?29.03±18.45).
(2)
The rank correlation coe ?cient is ?0.89and the signi?cance is of 99.99%.The lower panel of the same ?gure shows the line bisectors computed for all spectra of HD 166435,corrected for their RV and plotted on a common reference frame.Values of bisector velocity span and RV for individual spectra are listed in Table 1.The trend of the BVS obtained in this work is sim-ilar to that of Queloz et al.(2001);the larger value we found for the slope can be attributed to the higher resolution of the SARG spectra.
Table 2.Bisector velocity span from spectra of HD 8071B.87
lines were employed in the mask for the CCF.
1797.64110.3±34.0?80.9±13.7137
1854.54146.7±52.828.8±11.3912145.7171.6±34.9?98.7±11.41402297.38?1.0±44.4?177.7±12.91102892.6148.1±42.0?116.6±10.91122982.48300.3±62.8598.7±15.0923216.7339.9±33.8?78.7±11.01413246.6882.7±40.3?74.9±9.2121
8 A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG spectra
show any critical trend acting on the RV computation,leading
us to consider contamination as the cause of the observed correlation.The spectrum with RV ～600m s ?1and very di ?erent line pro?le is likely heavily contaminated by the companion,because of the occurrence of technical problems related to telescope tracking that night.Our study of the line bisector allows us to clearly identify the problematic spectrum and to exclude it from the analysis of the radial velocity curve.Nevertheless a correlation still persists even without consid-ering the highly discrepant spectrum,with a rank correlation coe ?cient 0.71and signi?cance of 92.9%.This is likely due to some residual contamination (of a few percent at most)by the companion,compatible with the small
separation of the pair and the actual observing conditions.Figure 7shows the two cases and the eight line bisectors computed for all spectra of HD 8071B,corrected for their RV and plotted on a common reference frame.Values of bisector velocity span and RV for individual spectra appear in Table 2.
To con?rm our hypothesis of contamination as the source of observed BVS-RV correlation,we performed a simple modeling of the expected contamination,excluding the highly discrepant spectrum from JD:2452982.48.We ?rst determined the light contamination expected on the spectrum of HD 8071B on the basis of the seeing conditions (given by the FWHM of the spectrum measured along a direction perpendicular to the dispersion).RV and BVS of HD 8071B do not show signi?cant correlation with such contamination.We then considered an “e ?ective contamination”as the product of the light contamination and the variable RV di ?erence between HD 8071A and B.The Spearman rank correlation coe ?cient of RV and BVS vs.such “e ?ective contamination”is 0.85with a signi?cance of more than 96%,supporting our hypothesis of light contamination as the origin of the RV and BVS variability of HD 8071B.The relation between RV perturbation and BVS is not linear likely because the RV perturbation due to contamination is expected to be a non-linear function of the position of the contamination across the line pro?le (See Figure 8).
4.3.51Peg
The star 51Peg (HD 217014)of spectral type G2.5IVa and visual magnitude m V =5.5is the ?rst discovered solar-type object to host a planet,with M 2sin i =0.47M J ,a =0.052AU and period of 4.23days (Mayor &Queloz 1995).
The star lies in a zone of the Hertzsprung-Russell diagram of stable (very low variability)objects (Eyer &Grenon 1997).Indeed,according to Henry et al.(2000),no measurable change in mean magnitude (over 5years)was seen and the Ca II record displayed a signal essentially constant despite some season-to-season jitter and a general indication of a low activity level.
Fifteen spectra of 51Peg were acquired between June 2001and November 2003.There is no signi?cant correlation between BVS and RV (rank correlation coe ?cient of ?0.28and signi?cance of 56%),con?rming the results by Hatzes et
Fig.9.Upper panel:plot of BVS vs.RV for 51Peg and the best ?t to a straight line.Lower panel:line bisectors for individ-ual spectra adjusted to their corresponding RV .The horizontal lines enclose the top and bottom zones considered for the ?tting analysis.74lines were employed in the mask for the CCF.
al.(1998)and Povich et al.(2001).The line bisector shape (see Figure 9)seems to be constant.
4.4.ρCrB
The star ρCrB (HD 143761)of spectral type G0Va and visual magnitude m V =5.4is known to host a planet with M 2sin i =1.04M J ,a =0.22AU and a period of 39.95days (Noyes et al.1997).
Twenty six spectra of ρCrB were acquired between April 2001and March 2004.In the plot of BVS against RV the dispersion of the data points shows no correlation (as in Povich et al.2001)with a rank correlation coe ?cient of 0.15and signi?cance of 52%.
The line bisectors and its behaviour,similar to those for 51Peg,are shown in Figure 10.The typical “C”shape of line bisectors is more evident for ρCrB in agreement with the
A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG spectra
9
Fig.10.Upper panel:plot of BVS vs.RV for ρCrB and the
best ?t to a straight line.Lower panel:line bisectors for individ-ual spectra adjusted to their corresponding RV .The horizontal lines enclose the top and bottom zones considered for the ?tting analysis.85lines were employed in the mask for the CCF.warmer temperature of the star.
4.5.HD 219542B
The star HD 219542B is member of a wide binary system,with spectral type G7V and visual magnitude m V =8.6.It was considered in Desidera et al.
(2003)as a candidate to host a planet,but ultimately discarded after further analysis;the small RV variations are more likely related to a moderate stellar activity (Desidera et al.2004a).
For the present analysis of the line bisectors,only the data of the 2002season were considered,twelve spectra,because the RV scatter and chromospheric activity were greater in this season (see Desidera et al.2004a).Therefore it should be easier to ?nd a correlation between BVS and RV from these data alone.
The plot of BVS against RV and the line bisectors are shown in Figure 11.No correlation appears in this case:the rank
Fig.11.Upper panel:plot of BVS vs.RV for HB 219542B and the best ?t to a straight line.Lower panel:line bisectors for individual spectra adjusted to their corresponding RV .The hor-izontal lines enclose the top and bottom zones considered for the ?tting analysis.86lines were employed in the mask for the CCF.
correlation coe ?cient is of ?0.37and the signi?cance of 76%.This lack of correlation is due to the small velocity amplitude (approximately between -17and 26m s ?1)and to the low S /N of the available spectra ～100.
5.Error analysis
An analytic study of errors was performed starting by consider-ing the internal BVS errors.The expected errors of BVS were computed for absorption pro?les obtained by convolution of Gaussian and rotational pro?les.The former were determined with a thermal broadening factor estimated by colors and temperatures of each star and the latter with a V sin i factor determined by the Fast Fourier Transform (FFT)analysis of each star’s absorption pro?le (Gray 1992).
The observed errors of BVS were the quadratic mean of the error bars of the single spectra.The observed BVS spread was
10 A.F.Mart′?nez Fiorenzano et al.:Line bisectors and radial velocity jitter from SARG spectra
Fig.12.The expected against observed errors of BVS(tri-
angles:quadratic mean of error bars).Squares correspond to
observed BVS spread against the measured BVS errors with
spread errors as error bars.
Table3.BVS errors:computed by eq.(1)in convolved pro?les
(expected)and measured from CCF pro?les(observed).
HD16643574.585.690.6a±27.3
HD8071B44.048.430.9a±11.7
51Peg18.019.125.3±6.8
ρCrB23.025.528.7±5.7
HD219542B39.044.031.5±9.5
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Torres,G.,Konacki,M.,Sasselov,D.D.,et al.2005,ApJ,619,558
门禁管理系统设计方案
1.1.门禁管理系统 1.1.1.概述 门禁管理系统是非接触式IC卡一卡通系统的子系统之一，同时也是大楼综合保安系统的重要组成部分，其设计之主要目的是为实现人员出入权限控制及出入信息记录。 当人员进门时只需持卡靠近读卡器进行读卡，读卡器接触到IC卡信息后，门禁控制器首先判断该卡号是否合法，如合法则发出“滴”一声，绿灯点亮，同时开锁，并将该卡号、日期、时间等信息保存以供查询。否则门不打开，红灯亮，蜂鸣器发出“滴滴”两声。 几乎在所有的一卡通系统中，门禁比重是最大的,对整个安防领域来说，门禁系统发挥的作用是至关重要的,由于门禁系统是一项不间断长期工作的系统，并且和我们的正常生活和工作息息相关，所以门禁系统的稳定性显得尤为重要。甚至可以说是决定一卡通系统稳定与否的最关键因素。 1.1. 2.系统架构与拓扑图 披克门禁系统TCP/IP一级结构方案，稳定可靠、功能全、性能好，性价比高，适应于各种大、小系统的不同应用场合；特别适应实时性要求高，或单个门用户量大、脱机信息存储量大的场合 TCP/IP一级结构控制器采用采用32位ARM9CPU，TCP/IP通讯，实时性强、能实时上传各种报警、数据信息；功能强大，持卡人数40000个（可扩10万个），信息10万条；适应实时性要求强、安全性高、功能全的场合，拓扑图如下：
1.1.3.门禁系统主要功能特点 1)系统容量大 整个系统管理的人员可以管理超过1000000人，具体到每个门可管理3000人进出，系统可以同时管理并处理上万个门禁点的实时数据（包括读卡、按钮、各种报警）。 2)简便易学、清晰鲜明的软件架构设计 全中文Windows XP风格软件操作界面，无需专业知识即刻轻松掌握，培训学习更加轻松．远离国外品牌繁琐复杂的操作培训 3)无缝兼容Wigand协议输入设备 核心科研机构、财务部门、数据机房等涉及金融、科研机密的高安全门禁，万一卡片遗失没有及时挂失，给不法分子可乘之机，财产的失窃、科研人员的研究成果泄密，将给用户单位造成不可挽回的损失，凡在安全级别高、人员少的门禁，披克建议： 1、密码读卡器，实现卡+密码方式双重认证 2、读卡前端采用指纹、面部、虹膜等生物识别 披克所有门禁系列产品都无缝兼容Wigand协议输入设备 4)多级权限控制
自动化英语单词
后验估计 a posteriori estimate 先验估计 a priori estimate 交流电子传动AC (alternating current) electric drive 验收测试acceptance testing 可及性accessibility 累积误差accumulated error 交-直-交变频器AC-DC-AC frequency converter 主动姿态稳定active attitude stabilization 驱动器，执行机构actuator 线性适应元adaline 适应层adaptation layer 适应遥测系统adaptive telemeter system 伴随算子adjoint operator 容许误差admissible error 集结矩阵aggregation matrix 层次分析法AHP (analytic hierarchy process) 放大环节amplifying element 模数转换analog-digital conversion 信号器annunciator 天线指向控制antenna pointing control 抗积分饱卷anti-integral windup 姿态轨道控制系统AOCS (attritude and orbit control system) 非周期分解aperiodic decomposition 近似推理approximate reasoning 关节型机器人articulated robot 配置问题，分配问题assignment problem 联想记忆模型associative memory model 联想机associatron 渐进稳定性asymptotic stability 实际位姿漂移attained pose drift 姿态捕获attitude acquisition 姿态角速度attitude angular velocity 姿态扰动attitude disturbance 姿态机动attitude maneuver 吸引子attractor 可扩充性augment ability 增广系统augmented system 自动-手动操作器automatic manual station 自动机automaton 自治系统autonomous system 间隙特性backlash characteristics 基座坐标系base coordinate system 贝叶斯分类器Bayes classifier 方位对准bearing alignment 波纹管压力表bellows pressure gauge 收益成本分析benefit-cost analysis 双线性系统bilinear system 生物控制论biocybernetics 生物反馈系统biological feedback system 黑箱测试法black box testing approach 盲目搜索blind search 块对角化block diagonalization 玻耳兹曼机Boltzman machine 自下而上开发bottom-up development 边界值分析boundary value analysis 头脑风暴法brainstorming method 广度优先搜索breadth-first search 蝶阀butterfly valve 计算机辅助工程CAE (computer aided engineering) 清晰性calrity 计算机辅助制造CAM (computer aided manufacturing) 偏心旋转阀Camflex valve 规范化状态变量canonical state variable 电容式位移传感器capacitive displacement transducer 膜盒压力表capsule pressure gauge 计算机辅助研究开发CARD 直角坐标型机器人Cartesian robot 串联补偿cascade compensation 突变论catastrophe theory 集中性centrality 链式集结chained aggregation 混沌chaos 特征轨迹characteristic locus 化学推进chemical propulsion 经典信息模式classical information pattern 分类器classifier 临床控制系统clinical control system 闭环极点closed loop pole 闭环传递函数closed loop transfer function 聚类分析cluster analysis 粗-精控制coarse-fine control 蛛网模型cobweb model 系数矩阵coefficient matrix 认知科学cognitive science 认知机cognitron 单调关联系统coherent system 组合决策combination decision 组合爆炸combinatorial explosion 压力真空表combined pressure and vacuum gauge 指令位姿command pose 相伴矩阵companion matrix 房室模型compartmental model 相容性，兼容性compatibility 补偿网络compensating network 补偿，矫正compensation
门禁管理系统说明
门禁管理系统 1.1.1 系统概述 采用现代信息传输技术、网络技术，结合非接触式IC卡技术，对建筑物各通道出入口实施门锁控制，并在系统中进行相关资料的记录与存储，对进出相关通道的人员实施管理。 1.1.2 门禁设计 在门禁系统服务器设置在网络中心。选用科学的系统结构，该系统采用分布式IP网络结构。各门禁控制器直接连接网络交换机（支持TCP/IP协议）与智能卡系统管理服务器之间建立双向数据通道从而构成完整的系统，各门禁控制器能够在网络不畅乃至通信中断时单独正常工作。网络门禁控制器由UPS 供电（接口？），网络门禁控制器采用加密进行通讯（如何加密？标准），其接入到就近的智能网交换机。 门禁管理子系统数据通过智能化专网提供数据传输链路。系统的管理工作站中心机房内（与消防控制中心合用），并连接一卡通管理服务器进行系统功能设置、发卡、权限控制统一管理。 达实门禁管理系统为两级控制，即：服务器→网络交换机→门禁控制器→门禁点设备（门禁感应器、电锁、门磁、开门按钮、紧急按钮等），无需其他中间设备。 1.1.3 系统功能 ?出入口管理系统采用1/2/4网络控制器，可以满足100万用户名单的记录，在跟服务器中心断开的情况下可自主读取并保持用户进出记录，待 网络恢复记录会自动上传至智能卡管理服务器，每个门禁控制器均有 100000条事件记录的存储容量和5000条报警事件，5000条巡更记录。 ?存储各门控的所有用户名单及权限信息
?支持用户名单和记录数量均是100,000 ?设备支持TCP、RS485等多种通讯方式，通讯电路具备自检功能，损坏后自动断开，不会影响其它设备稳定运行 ?支持256个时间段，16个时间组，128个节假日同时，每个时段允许设定运行模式（常开/常闭），支持卡、密码、卡或密码、卡加密码等认证方式，验证组合(比如首卡、多卡等)，支持节假日及调休配置； ?定时开关门: 支持非节假日定时开关门。 ?设备存储空间大，采用双存储芯片实现名单与记录隔离 ?支持脱机、实时多种运行模式 ?开门控制方式多样化：刷卡、按钮、计算机远程、公共密码、胁迫密码、卡+密码、多卡开门、多卡多群组开门、首卡常开、首卡启动 ?支持多种组合控制类型：单向门、双向门、反潜回门、互锁门 ?支持跨网段通讯 ?存储各门控的通行数据、报警数据、日志数据 ?针对门控级别的多门互锁 ?支持半联机及实时状态下的用户权限判断 ?针对门控级别的防潜回功能 ?针对门控故障更换设备时的触发式数据下载 ?随时切换门禁运行模式（常开/常闭） ?支持门禁数据WEB浏览 ?支持远程开门功能 ?门锁控制：控制门锁开与关，亦可加装门磁设备，实时监测门开关状态；?远程控制：在管理中心可通过系统软件远程控制门锁的开、关，并能实时监控门禁的开关情况； ?远程设置：在管理中心可通过管理软件随时更改门禁工作状态和运行参数； ?用户管理：支持用户级别设置及级别分配，用户级别采用全灵活配置以支持普通用户、超级管理员及胁迫用户等；对人员的权限及时限进行统一管理，可按个人及团体两种方式进行权限的设置及下载；
velocity入门使用教程
V elocity入门使用教程 一、使用velocity的好处： 1.不用像jsp那样编译成servlet（.Class）文件，直接装载后就可以运行了，装载的过程在web.xml里面配置。【后缀名为.vhtml是我们自己的命名方式。也只有在这里配置了哪种类型的文件，那么这种类型的文件才能解析velocity语法】 2.web页面上可以很方便的调用java后台的方法，不管方法是静态的还是非静态的。只需要在toolbox.xml里面把类配置进去就可以咯。【调用的方法$class.method()】即可。 3.可以使用模版生成静态文档html【特殊情况下才用】 二、使用 1、下载velocity-1.7.zip 、velocity-tools-2.0.zip 2、解压后引用3个jar文件velocity-1.7.jar、velocity-tools-2.0.jar、velocity-tools-view-2.0.jar 还有几个commons-…..jar 开头的jar包 三、配置文件： Web.xml
科技英语语法_同位语从句_名词性从句_定语从句
2015/12/2 Wednesday
西安电子科技大学
西安电子科技大学
§5. 2 同位语从句
1、一般情况 （1）公式
§5. 2 同位语从句 The latter（后一）form has the advantage that it can be extended（扩展） to complex quantities .
+ 某些抽象名词 +
the this a/an O no
形容词 物主代词
that从句[“that”在
从句中无词义、无 成分]
③ “动宾译法”：这时该“抽象名词” 来自于可带有宾语从句的及物动词。
西安电子科技大学
西安电子科技大学
§5. 2 同位语从句
（2）译法 ① “～ 这一 ……” 的
§5. 2 同位语从句 During the past several years, there has been an increasing [a growing] recognition [realization; awareness] within business（商务）and academic（学术的） circles（界）that certain nations have evolved（发展）into information societies .
The assumption that β = constant is often made to simplify analysis. R = r is the condition that power delivered（提供）by a given source is a maximum .
西安电子科技大学
西安电子科技大学
§5. 2 同位语从句 Here we have used the definition （定义）that acceleration（加速度）is the rate（速率）of change of velocity .
② 这一 ……：～ 以下的
§5. 2 同位语从句 The main theoretical development in this decade（十年）has been in the recognition that material properties should be included in analytical models . This is equivalent to a statement that everything is attracted by the earth.
This account for（解释）the observation（观察到的情况）that the resistivity of a metal increases with temperature .
1
VRay中文使用手册
VRay中文使用手册 9030 目录 1. license 协议 2. VRay的特征 3. VRay软件的安装 4. VRay的渲染参数 5. VRay 灯光 6. VRay 材质 7. VRay 贴图 8. VRay 阴影 9. VRay的分布式渲染 10. Terminology术语 11. Frequently Asked Questions常见问题 VRay的特征 VRay光影追踪渲染器有Basic Package 和 Advanced Package两种包装形式。Basic Package具有适当的功能和较低的价格，适合学生和业余艺术家使用。Advanced Package 包含有几种特殊功能，适用于专业人员使用。 Basic Package的软件包提供的功能特点
·真正的光影追踪反射和折射。(See: VRayMap) ·平滑的反射和折射。(See: VRayMap) ·半透明材质用于创建石蜡、大理石、磨砂玻璃。(See: VRayMap) ·面阴影(柔和阴影)。包括方体和球体发射器。(See: VRayShadow) ·间接照明系统(全局照明系统)。可采取直接光照 (brute force), 和光照贴图方式（HDRi）。(See: Indirect illumination) ·运动模糊。包括类似Monte Carlo 采样方法。(See: Motion blur) ·摄像机景深效果。(See: DOF) ·抗锯齿功能。包括 fixed, simple 2-level 和 adaptive approaches等采样方法。(See: Image sampler) ·散焦功能。(See: Caustics ) ·G-缓冲(RGBA, material/object ID, Z-buffer, velocity etc.) (See: G-Buffer ) Advanced Package软件包提供的功能特点 除包含所有基本功能外，还包括下列功能： ·基于G-缓冲的抗锯齿功能。(See: Image sampler) ·可重复使用光照贴图 (save and load support)。对于fly-through 动画可增加采样。(See: Indirect illumination) ·可重复使用光子贴图 (save and load support)。(See: Caustics) ·带有分析采样的运动模糊。(See: Motion blur ) ·真正支持 HDRI贴图。包含 *.hdr, *.rad 图片装载器，可处理立方体贴图和角贴图贴图坐标。可直接贴图而不会产生变形或切片。
门禁考勤管理系统操作说明书
门禁考勤管理系统（V1.11/V1.15） 操 作 用 说 明 书
目录 一、前言 (4) 二、软件安装 1、系统要求 (6) 2、安装 (6) 3、卸载 (8) 三、操作说明 (10) 1、系统管理 (11) 2、人事管理 (19) 3、考勤管理 (21) 4、查询 (24) 5、数据管理 (25)
四、操作流程 (30) 五、常见故障与解决方法 (30) 前言： 软件安装默认目录：C: \Program Files\门禁考勤管理系统,(建议安装到D:\Program Files\门禁考勤管理系统) 。在WIN2000系统安装时，一定要以管理员帐号登陆WIN2000系统才能安装；否则安装运行门禁考勤管理软件时会出错！ 硬件建议：赛扬1.5G或PIII 1.0G以上，128M内存，20G硬盘7200转以上补充说明： 1.如果安装完后运行门禁考勤管理系统时出现如下错误：“连接数据出错” 请作出如下调整： A.在控制面板中‘“区域选项”日期设为{yyyy-mm-dd}的形式，时间设为 {hh:mm:ss}的形式 做完A步骤后如果再出现“连接数据出错”再做B步骤 B.在控制面板中的ODBC项中建立一个的ODBC是HYkaoqin 的ODBC
到控制面板中的ODBC项双击“数据源(ODBC)” 进入以下界面后，点击选择：MS Access Database,再点击“添加” 再进入如下界面再点击“完成”
进入如下界面，在“数据源名（N）”输入：Hykqoqin然后点击“确定” 创建完毕。
门禁考勤网络结构图： Com口 485转换器
智能门禁管理系统
智能门禁管理系统 门禁管理系统概述 与传统钥匙门锁相比，门禁系统在携带，遗失等情况时的处理更加方便，无须更换大量门锁和钥匙，仅需要在软件中做出相应的操作即可。与监控、报警等安防方式相比，门禁系统化被动为主动，将安全隐患直接排除在管制通道之外。 门禁管理系统功能 灵活丰富的权限管制： 通过时区、周计划、假期信息、管制群组的自由设置可以控制任何一个持卡人在任何一个房门的任意时刻的开门权限和开门方式。◆通道管制、胁迫报警： 系统允许对某些房门进行管制，实行手动或自动布防和撤防，布防时间内仅系统卡和警卫卡才具有开门权限。胁迫报警是指发生不法分子挟持合法用户强迫开门事件时具备报警机制。 ◆强大的报警设置功能： 系统具有胁迫报警、防撬报警、强行进入报警、超时报警和反潜回功能。 ◆电子公告功能： 在具备液晶的读卡器上具有立方独特的电子公告功能，通过软件编辑后可向读卡机发布自定义的电子公告，用户刷卡后即可显示该短信息。 ◆强大的系统联动： 用户可以对系统的各个I/O口进行功能设置，实现与第三方系统或一卡通其他子系统进行联动。 ◆多种开门方式：
系统支持多种开门方式，如刷卡开门、密码开门、刷卡+密码开门、刷卡+密码+触发开门、刷多卡开门方式等，可根据不同的安全需求进行灵活的选择。 ◆动态电子地图显示： 系统具有电子地图，在电子地图上实时的以图形和文字的形式显示事件，如刷卡事件、进出房门、门状态变化、系统报警和各种紧急事件等。 可以输入多幅地图，从不同角度监控现场出入情况。 ◆具备多种发卡方式： 系统可以用连接电脑的发卡器或连接控制器的读卡器发卡、也可以先由控制器发卡后上传到数据库再指定用户。◆互锁通道、反潜回： 系统允许管理员对指定的通道或房门实行互锁，互锁组的房门在同一时间只能开启其中的一扇。反潜回指在合法卡刷卡进入后，必须再规定时间内外出。 ◆自动与手动的布防/撤防： 系统支持对指定房门的自动布防和撤防功能，可以在有权限的情况下指定某些房门在到达指定的时间段内处于布防状态，过了这段时间之后，系统会自动撤防；也允许在有限的条件下，随时对房门进行布防和撤防操作。 门禁管理系统优势 ◆安全： 圣坤科技门禁系统本身具备了企业级的密钥认证体系、严格的通信协议加密体系、完善的数据库安全管理体系,具有极高的系统安全性能；产品外壳坚固耐用，具备防水、防撬设计；在业务上从专业的安防角度出发，设计了最完善全面的安全功能，包括多卡认证、自动布防/撤防、反胁迫、反潜回、通道互锁、强行进入、防撬报警等，可以实现客户对系统安全性最细微的需求。 ◆美观：
fluent 使用基本步骤
fluent 使用基本步骤 步骤一：网格 读入网格（*．msh） File →Read →Case 读入网格后，在窗口显示进程 检查网格 Grid →Check Fluent对网格进行多种检查，并显示结果。注意最小容积，确保最小容积值为正。 显示网格 Display →Grid 以默认格式显示网格 能够用鼠标右键检查边界区域、数量、名称、类型将在窗口显示，本操作关于同样类型的多个区域情形专门有用，以便快速区不它们。 网格显示操作 Display →Views 在Mirror Planes面板下，axis 点击Apply,将显示整个网格 点击Auto scale, 自动调整比例，并放在视窗中间 点击Camera,调整目标物体位置 用鼠标左键拖动指标钟，使目标位置为正 点击Apply，并关闭Camera Parameters 和Views窗口 步骤二：模型 1. 定义瞬时、轴对称模型 Define →models→Solver 保留默认的，Segregated解法设置，该项设置，在多相运算时使用。
在Space面板下,选择Axisymmetric 在Time面板下，选择Unsteady 2. 采纳欧拉多相模型 Define→Models→Multiphase (a) 选择Eulerian作为模型 （b）如果两相速度差较大，则需解滑移速度方程 （c）如果Body force比粘性力和对流力大得多，则需选择implicit b ody force 通过考虑压力梯度和体力，加快收敛 （d）保留设置不变 3. 采纳K-ε湍流模型（采纳标准壁面函数） Define →Models →Viscous (a) 选择K-ε( 2 eqn 模型) (b) 保留Near wall Treatment面板下的Standard Wall Function设置 在K-εMultiphase Model面板下，采纳Dispersed模型，dispersed湍流模型在一相为连续相，而材料密度较大情形下采纳，而且Stocks数远小于1，颗粒动能意义不大。 4．设置重力加速度 Define →Operating Conditions 选择Gravity 在Gravitational Acceleration下x或y方向填上－9.81m/s2 步骤三：材料 Define →Materials 复制液相数据作为差不多相 在Material面板。点击Database, 在Fluid Materials 清单中，选Water -Liquid (h2o(1))
词缀在英语词汇中的运用
词缀在英语词汇中的运用—— 浅淡构词法中的后缀 The Application of Affixes in English Vocabulary Memorization— A Brief Study on suffix of English Word Formation 摘要：词汇是英语学习者的主要障碍之一。它在运用语言进行交际过程中至关重要，它直接影响听、说、读、写各项能力的发挥，好么对于语言学习者来说，首先就要克服这个障碍。英语构词法可以帮助我们正确辩认单词的词形，词性和理解词意，并迅速扩大词汇量，有助于提高英语的阅读速度和理解能力，是学习英语和提高学习质量的有效的方法，被誉为“学习英语的最短最佳的途径”。而构词法中的后缀是构词能力最强的一种，也是英语扩充词汇的最主要的方法之一。后缀是加在词根或单词后面的部分，通常把它们的词性改变为名词、形容词、动词和副词[4]。一旦掌握这些规律，对词汇的获得就不再是那么困难了，而且还会大大激发学习兴趣，也就解决了学习者对词汇的习得的困难了，从而就能更有效地学习和掌握英语了。 关键词：英语词汇；英语构词法；后缀。 Abstract:Vocabulary is one of the main obstacles to the English learners.It is extremely crucial in the process of communication by using language,it directly influences the development of the ability of listening,speaking,reading,writing ect.therefore we must overcome the obstacle first as language learners. English Word Formation can help us distinguish the form and nature of word and apprehend the maening of word correctly,and enlarge our vocabulary quickly .It can help us enhance the velocity of reading English and the ability of apprehension.It is an efficient way and powerful weapon for English study ,and it is claimed to be one of the shortest and best way of English study.Affixation is one of the efficient ways of learning
LAMMPS手册中文讲解
LAMMPS手册-中文解析 一、简介 本部分大至介绍了LAMMPS的一些功能和缺陷。 1．什么是LAMMPS? LAMMPS是一个经典的分子动力学代码，他可以模拟液体中的粒子，固体和汽体的系综。他可以采用不同的力场和边界条件来模拟全原子，聚合物，生物，金属，粒状和粗料化体系。LAMMPS可以计算的体系小至几个粒子，大到上百万甚至是上亿个粒子。 LAMMPS可以在单个处理器的台式机和笔记本本上运行且有较高的计算效率，但是它是专门为并行计算机设计的。他可以在任何一个按装了C++编译器和MPI的平台上运算，这其中当然包括分布式和共享式并行机和Beowulf型的集群机。 LAMMPS是一可以修改和扩展的计算程序，比如，可以加上一些新的力场，原子模型，边界条件和诊断功能等。 通常意义上来讲，LAMMPS是根据不同的边界条件和初始条件对通过短程和长程力相互作用的分子，原子和宏观粒子集合对它们的牛顿运动方程进行积分。高效率计算的LAMMPS通过采用相邻清单来跟踪他们邻近的粒子。这些清单是根据粒子间的短程互拆力的大小进行优化过的，目的是防止局部粒子密度过高。在并行机上，LAMMPS采用的是空间分解技术来分配模拟的区域，把整个模拟空间分成较小的三维小空间，其中每一个小空间可以分配在一个处理器上。各个处理器之间相互通信并且存储每一个小空间边界上的”ghost”原子的信息。LAMMPS(并行情况)在模拟3维矩行盒子并且具有近均一密度的体系时效率最高。 2．LAMMPS的功能 总体功能：
可以串行和并行计算 分布式MPI策略 模拟空间的分解并行机制 开源 高移植性C++语言编写 MPI和单处理器串行FFT的可选性（自定义） 可以方便的为之扩展上新特征和功能 只需一个输入脚本就可运行 有定义和使用变量和方程完备语法规则 在运行过程中循环的控制都有严格的规则 只要一个输入脚本试就可以同时实现一个或多个模拟任务粒子和模拟的类型： （atom style命令） 原子 粗粒化粒子 全原子聚合物，有机分子，蛋白质，DNA 联合原子聚合物或有机分子 金属 粒子材料 粗粒化介观模型 延伸球形与椭圆形粒子 点偶极粒子
门禁管理系统方案
3.8门禁管理 3.8.1总体性能要求 ?系统是利用现代计算机网络通信及大型数据库为技术基础，基于WINDOWS 管理平台建立统一的“一卡通”综合管理系统。 ?系统采用模块化设计方法，每个子系统的软硬件保持较大的冗余度。某部分出现问题不会影响其它子系统的正常运行。 ?各子系统统一管理平台，实现所有子系统的设备在管理中心集中管理，权限统一制授，用户卡的挂失、消权等集中处理，并记录跟踪卡片发生数据。 ?门禁和闭路监控的联动方式采用硬件方式，当非法入侵时，监视显示器中弹出相应报警画面，并产生报警信号。 ?主干及分支网络：门禁业务主机可控制和管理下级的所有门禁系统硬件设备，各子系统管理电脑、管理中心以组网方式相联。 ?安全管理：系统管理人员权限采用模块化分配和多级管理。 3.8.2技术细则 证卡制作中心： 证卡制作中心是感应IC卡（一卡通系统）的管理中心，主要功能包括： ?制定IC卡应用法规； ?统一制作、管理和维护用户卡片； ?补发和注销工作人员和管理卡（含有有效期限）； ?协调行内本系统各子系统之间IC卡应用中的关系； ?整套“一卡通”系统配置管理； ?提供一卡通查询系统； ?提供密码、时间、区域、等级优先等多种安全模式控制。 3.8.3、一楼保安监控中心： 保安监控中心是xxxxx医院新建医疗大楼安防系统的枢纽，在本系统中主要设计完成
下列功能： ?设置门禁、门锁监控主机，监控整个门禁、门锁系统的运作和查询； ?各管制通道进出实时监控； ?当门非法打开时提供报警信息； ?与消防、闭路监控系统联动； ?紧急开门； 3.8.4、智能发卡子系统 ?制定IC卡应用法规； ?统一制作、管理和维护用户卡片； ?补发和注销IC卡； ?协调各部门之间IC卡应用中的关系。 3.8.5系统设计 3.8.5.1、一卡通系统数据流特点 如一卡通系统网络数据流示意图所示，一卡通系统的数据交换方式可分为两类： （1）业务数据流： 它是指一卡通子系统内从服务器到工作站，工作站到服务器及各工作站之间的数据流，通过大厦局域网进行传输。一卡通系统的业务数据流都触发对数据库的某种操作。由于一卡通系统的各个模块功能可能分布于不同的部门，为使这些模块之间的数据同步和实现快速高效的WEB查询，中央数据库是必须的。同时，为了减轻服务器的负担，又要尽量做到数据的分布式处理。这使一卡通系统的数据库分为两部分：《1》中央数据库：位于服务器上。《2》本地库：运行在各管理子系统工作站上。本地库与中央数据库之间的同步数据流有三个方向： a) 中央数据库------》本地库； b) 本地库--------》中央数据库；
Velocity教程
Velocity教程 关键字: velocity教程 Velocity是一个基于java的模板引擎（template engine）。它允许任何人仅仅简单的使用模板语言（template language）来引用由java代码定义的对象。当Velocity应用于web开发时，界面设计人员可以和java程序开发人员同步开发一个遵循MVC架构的web站点，也就是说，页面设计人员可以只关注页面的显示效果，而由java程序开发人员关注业务逻辑编码。Velocity将java代码从web页面中分离出来，这样为web站点的长期维护提供了便利，同时也为我们在JSP和PHP之外又提供了一种可选的方案。 官方网站：https://www.wendangku.net/doc/4410481186.html,/velocity/ Velocity脚本摘要 1、声明:#set ($var=XXX) 左边可以是以下的内容 Variable reference String literal Property reference Method reference Number literal #set ($i=1) ArrayList #set ($arr=["yt1","t2"]) 技持算术运算符 2、注释: 单行## XXX 多行#* xxx xxxx xxxxxxxxxxxx*# References 引用的类型 3、变量Variables 以"$" 开头，第一个字符必须为字母。character followed by a VTL Identifier. (a .. z or A .. Z). 变量可以包含的字符有以下内容： alphabetic (a .. z, A .. Z) numeric (0 .. 9) hyphen ("-") underscore ("_") 4、Properties $Identifier.Identifier $https://www.wendangku.net/doc/4410481186.html,
从句语法知识及真题解析
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GOCAD中文手册
GOCAD综合地质与储层建模软件 简易操作手册 美国PST油藏技术公司 PetroSolution Tech,Inc.
目录 第一节 GOCAD综合地质与储层建模软件简介┉┉┉┉┉┉┉┉┉┉┉┉┉┉1 一、GOCAD特点┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉1 二、GOCAD主要模块┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉1 第二节 GOCAD安装、启动操作┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉2 一、GOCAD的安装┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉2 二、GOCAD的启动┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉3 第三节 GOCAD数据加载┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉5 一、井数据加载┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉5 二、层数据加载┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉11 三、断层数据加载┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉11 四、层面、断层面加载┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉12 五、地震数据加载┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉12 第四节 GOCAD构造建模┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉13 一、准备工作┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉13 二、构造建模操作流程┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉14 三、构造建模流程总结┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉40 第五节建立GOCAD三维地质模型网格┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉41 一、新建三维地质模型网格流程┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉41 二、三维地质模型网格流程┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉41 三、三维地质模型网格流程总结┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉47 第六节 GOCAD储层属性建模┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉48 一、建立属性建模新流程┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉48 二、属性建模操作流程┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉48 三、属性建模后期处理┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉66 四、网格粗化┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉74 第七节 GOCAD地质解释和分析┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉┉78