Stellar Velocity Dispersion of the Leo A Dwarf Galaxy
a r X i v :0705.1093v 1 [a s t r o -p h ] 8 M a y 2007
Accepted in ApJ
Preprint typeset using L A T E X style emulateapj v.10/09/06
STELLAR VELOCITY DISPERSION OF THE LEO A DWARF GALAXY
Warren R.Brown,Margaret J.Geller,Scott J.Kenyon,Michael J.Kurtz
Smithsonian Astrophysical Observatory,60Garden St,Cambridge,MA 02138
Accepted in ApJ
ABSTRACT
We measure the ?rst stellar velocity dispersion of the Leo A dwarf galaxy,σ=9.3±1.3km s ?1.We derive the velocity dispersion from the radial velocities of ten young B supergiants and two H ii regions in the central region of Leo A.We estimate a projected mass of 8±2.7×107M ⊙within a radius of 2′,and a mass to light ratio of at least 20±6M ⊙/L ⊙.These results imply Leo A is at least ～80%dark matter by mass.
Subject headings:galaxies:individual (Leo A)
1.INTRODUCTION
The Leo A dwarf galaxy was discovered by Zwicky (1942)and is one of the most remote galaxies in the Local Group.Leo A is gas rich,with an H i velocity dispersion of 3.5to 9km s ?1and with no observed ro-tation (Allsopp 1978;Lo et al.1993;Young &Lo 1996).Leo A is also extremely metal poor,with an abundance of 12+log O /H =7.3to 7.4measured from H ii regions (Skillman et al.1989;van Zee et al.2006).
Photometric studies of Leo A reveal both a red and blue plume of stars in its color-magnitude diagram indicating recent star formation (Demers et al.1984;Sandage 1986;Tolstoy 1996).Hubble Space Telescope observations have resolved the stellar population of Leo A,which shows evidence for numerous epochs of star formation spanning billions of years (Tolstoy et al.1998;Schulte-Ladbeck et al.2002;Cole et al.2007)as well as an old stellar “halo”(Vanseviˇc ius et al.2004).RR Lyrae variables con?rm the presence of an ～11Gyr old pop-ulation,and place Leo A at a distance of 800±40kpc (Dolphin et al.2002).Recently,Brown et al.(2006)re-ported the ?rst spectroscopy of stars in Leo A:two B su-pergiants stars observed serendipitously as part of their hypervelocity star survey.The B supergiants provide spectroscopic proof of star formation as recently as ～30Myr ago in Leo A.
Inspired by the B supergiant observations,we have ob-tained spectroscopy for ten additional blue-plume objects in Leo A.There is no a-priori reason to expect that Leo A’s steller and H i gas velocity dispersions are identi-cal.Detailed H i maps show velocity structure,which suggests that the gas may be a?ected by cooling or may not yet be relaxed (Young &Lo 1996).Our observations allow us to measure the stellar velocity dispersion,and thus estimate the mass of Leo A’s dark matter halo.In §2we discuss our target selection,observations,and stellar radial velocity determinations.In §3we present the re-sulting velocity dispersion and mass-to-light ratio of Leo A.We conclude in §4.
2.DATA
2.1.Target Selection
We use Sloan Digital Sky Survey (SDSS,Adelman-McCarthy et al.2007)photometry to se-Electronic address:wbrown@https://www.wendangku.net/doc/9b3281455.html,
lect candidate Leo A blue plume stars by color.We illustrate our target selection in Figure 1,a color-color diagram of every star in SDSS Data Release 5with g ′<21and within 9′of Leo A (see also Figure 2).We compute de-reddened colors using extinction values obtained from Schlegel et al.(1998);the adopted extinc-tion values are E (u ′?g ′)=0.029and E (g ′?r ′)=0.022.Objects with (g ′?r ′)0<0and (u ′?g ′)0<1.1are objects in the blue plume.The blue plume can contain massive main sequence stars,blue supergiant stars,and blue-loop stars (e.g.Schulte-Ladbeck et al.2002).We target the 12blue plume objects with g ′<21(solid squares and triangles).
Objects with (g ′?r ′)0>0in Figure 1have colors consistent with foreground stars,ranging from F-type stars at the main sequence turn-o?(g ′?r ′)0～0.2to late M dwarfs (g ′?r ′)0>1.Stars with (g ′?r ′)0～1.4may include some asymptotic giant branch stars in Leo A.
Figure 2plots the position of every star in Figure 1.For reference,the ellipses follow Leo A’s observed H i pro?le,with center 9h 59m 23.s 92+30?44′47.′′69(J2000),semiminor to semimajor axis ratio 0.6,and position angle 104?(Young &Lo 1996).The solid ellipse marks Leo A’s
Holmberg radius a =3.′
5(Mateo 1998),and the dotted
ellipse with a =8.′
0marks the extent of Leo A’s H i gas (Young &Lo 1996)and stellar “halo”(Vanseviˇc ius et al.2004).All twelve blue plume candidates are located within 2′of the center of Leo A;probable foreground objects are distributed more uniformly across the ?eld.
2.2.Observations
We obtained spectroscopy of the twelve blue plume ob-jects with the 6.5m MMT telescope and the Blue Channel spectrograph.Observations occurred during the course of our hypervelocity star survey program on the nights of 2005Dec 5-6,2006May 24-25,2006June 20,2006Dec 27,and 2007Mar 18.We operated the Blue Chan-nel spectrograph with the 832line mm ?1grating in 2nd order and with a 1.25′′slit.These settings provided a wavelength coverage of 3650?A to 4500?A and a spectral
resolution of 1.2?A .One object (an H ii region)was re-observed with the 300line mm ?1grating and a 1′′slit,
providing wavelength coverage from 3400?A to 8600?A
with a spectral resolution of 6.2?A .Exposure times were
30minutes.We obtained comparison lamp exposures af-
2Brown et
al.
Fig.1.—Color-color diagram of every star in SDSS with g ′<21and within 9′of Leo A (centered at 9h 59m 23.s 92+30?44′47.′′69J2000).We target the twelve blue plume candidates with (g ′?r ′)0<0.We identify ten B supergiants (solid squares )and two H ii regions (solid triangles ).
ter every exposure.The wavelength solutions are deter-mined from 44lines with typical root-mean-square resid-uals of ±0.05?A ,or ±4km s ?1.We note that the single slit spectrograph is a compact instrument with minimal ?exure:wavelength solutions shift by less than 1pixel (0.355?A )during a night,easily measured from individ-ual comparison lamp exposures.
2.3.Spectroscopic Identi?cations
Ten blue plume objects
are stars of B spectral type and two are H ii regions.Figure 3plots the spectra of the ten stars and the two H ii regions,summed and shifted to the rest frame.The signal-to-noise ratios (S/N )of the individual spectra range from S/N =6to 15per pixel at 4000?A ,and depend on target’s apparent magnitude and the seeing conditions of the observation.
The ten B-type stars have visibly narrower Balmer lines and thus lower surface gravity than the other B-type stars in the Brown et al.(2006,2007)hypervelocity star survey.Cross-correlation with MK spectral standards (Gray et al.2003)indicates that the stars are probably luminosity class I or II B supergiants,consistent with the stars’inferred luminosities.
At the distance modulus of Leo A (m ?M )0=24.51±0.12(Dolphin et al.2002),the ten B-type stars have ab-solute magnitudes ranging from M V =?5.3to ?3.4.For comparison,Corbally &Garrison (1984)give absolute magnitudes M V =?5.5for a B9Ib star and M V =?3.1for a B9II star.We conclude the ten stars are likely B supergiants in Leo A.Such B supergiants have ages rang-ing from ～30Myr for the most luminous stars to ～200Myr for the least luminous stars (Schaller et al.1992).
2.4.Radial Velocities
We measure radial velocities with the cross-correlation package RVSAO (Kurtz &Mink 1998).We begin by ob-serving the B9II star γLyr by quickly scanning the star across the spectrograph slit.This procedure provides us with a very high signal-to-noise ratio cross-correlation
Fig. 2.—Location of objects in Figure 1,where the symbols are the same as before.For reference,the solid ellipse marks Leo
A’s Holmberg radius a =3.
′5(Mateo 1998)and the dotted ellipse marks the extent of Leo A’s stellar “halo”(Vanseviˇc ius et al.2004)and H i gas (Young &Lo 1996).
template with a known velocity (Evans 1967;Gray et al.2003).The accuracy of the velocity zero-point comes from the error on the mean of the 44comparison lamp lines used to determine the template’s wavelength solu-tion,±0.6km s ?1.
Is is important that we maximize velocity precision for our velocity dispersion measurement,and we achieve the best precision by cross-correlating the stars with them-selves.Thus,after measuring the stars’velocities with the γLyr template,we shift the spectra to the rest frame and sum them together to create a second tem-plate (shown in Figure 3).We then cross-correlate the ten stars with this second template of themselves.Ta-ble 1lists the resulting heliocentric radial velocities and errors.The mean cross-correlation precision is ±3.7km s ?1.
We also measure the radial velocities of the H ii regions with RVSAO,but this time using Gaussian ?ts to the emission lines.The ?nal velocity of SDSS J095927.532+304457.75comes from a weighted mean of the 3727[O ii ]doublet (resolved in our spectra),H δ,and H γemission lines.A low-dispersion spectrum of SDSS J095933.320+304439.21provides additional line measurements from H β,[O iii ],and H αfor that ob-ject.The velocity of SDSS J095933.320+304439.21is the weighted average of all of its observed lines.The mean emission-line velocity error is ±3.9km s ?1.
3.RESULTS
3.1.Stellar Velocity Dispersion
The average velocity of our twelve Leo A objects is 22.3±2.9km s ?1(see Figure 4),statistically identical with the 23±3km s ?1systemic H i velocity measured by Allsopp (1978)and the 23.2-24.0km s ?1systemic H i velocities measured by Young &Lo (1996).Thus the velocities of our twelve objects are all consistent with membership in Leo A.
The root-mean-square velocity dispersion of our twelve objects is 10.0km s ?1.We derive the intrinsic velocity
Stellar Velocity Dispersion of Leo A
3
Fig.3.—MMT spectra of the ten B supergiants (upper panel )and the two H ii regions (lower panel ),summed together and shifted to rest frame.The continuum ?uxes are arbitrarily nor-malized.
dispersion by subtracting in quadrature the average 3.8km s ?1uncertainty of the observations.Thus we measure an intrinsic stellar velocity dispersion of σ=9.3±1.3km s ?1.
We estimate the robustness of the velocity dispersion measurement by comparing the cumulative distribution of velocities to a Gaussian distribution (see Figure 4).A Kolmogorov-Smirnov test ?nds a 0.5likelihood of draw-ing the twelve objects from a Gaussian distribution with the observed velocity dispersion.Greater number statis-tics are always desirable,but it appears that the twelve blue plume objects provide a statistically sound measure-ment of Leo A’s stellar velocity dispersion.
Our stellar velocity dispersion measurement is iden-tical to the H i gas velocity dispersion measured by Young &Lo (1996):9.3±1.4km s ?1.Young &Lo (1996)also observe an H i component with 3.5±1.0km s ?1dispersion localized in high column-density regions.If we remove the two H ii regions from our own analysis,the B-type stars have a mean velocity of 21.5±3.4km s ?1and an intrinsic velocity dispersion of σB =10.1±1.3km s ?1.This dispersion is statistically identical to our original value.
There is no evidence for rotation of the stellar com-ponent of Leo A;the high-and low-velocity blue plume objects appear inter-mixed on the sky.This result is consistent with absence of rotation seen in the H i gas (Lo et al.1993;Young &Lo 1996).Given that detailed H i maps show velocity structure in Leo A (Young &Lo 1996),it is possible that additional observations may re-veal structure in the stellar radial velocity distribution.
3.2.Mass-to-Light Ratio
We now estimate the kinematic mass of Leo A.Because there is no evidence for rotation,we assume that the galaxy is in pressure equilibrium and apply two simple mass estimators:the virial theorem,and the projected mass estimator of Heisler et al.(1985).The virial mass is
given by M vir =696R e σ2
z M ⊙,where R e is the e?ective
radius in pc and σz is the one-dimensional velocity dis-
Fig. 4.—Cumulative distribution of the observed velocities (histogram )compared to a Gaussian distribution (curve )with dis-persion 10.0km s ?1and mean velocity 22.3km s ?1.
persion in km s ?1.Our objects are located inside a radius of 2′=500pc,while Leo A’s observed stellar distribu-tion extends to a radius of 8′=2000pc.If we choose R e =500pc,Leo A’s virial mass is M vir ～3×107M ⊙.The virial theorem,however,is both more biased and less stable for small numbers of test particles than is the projected mass estimator (Bahcall &Tremaine 1981).Thus we use the Heisler et al.(1985)projected mass es-timator to obtain a more accurate estimate of Leo A’s mass:
M proj =
f
4Brown et al.
TABLE 1
LEO A BLUE PLUME OBJECTS
RA Dec type v helio
g ′(u ′?g ′)0
(g ′?r ′)0
J2000J2000km s
?1
mag mag mag 9:59:15.12430:44:10.40B 23.0±2.519.8960.761-0.2799:59:16.94030:43:48.22B 21.7±5.219.050-0.021-0.3539:59:20.22330:43:52.71B 34.0±2.819.4350.458-0.3759:59:23.22030:45:06.23B 7.4±3.820.0260.584-0.3479:59:24.90930:44:36.69B 30.9±3.419.797 1.004-0.2579:59:25.98030:46:10.44B 9.5±5.020.9640.652-0.3979:59:26.35130:45:26.09B 37.6±2.319.1310.412-0.3009:59:27.05830:45:38.79B 21.9±4.720.2670.982-0.3889:59:27.32630:45:44.69B 7.6±4.920.661 1.082-0.4209:59:27.53230:44:57.75H ii 30.0±3.619.984-0.238-0.6079:59:32.12930:43:48.55B 22.0±2.620.4710.383-0.3609:59:33.320
30:44:39.21
H ii
22.2±4.2
19.520
-0.288
-0.252
is 4×106L ⊙.Thus the mass-to-light ratio of Leo A is M/L tot =20±6M ⊙/L ⊙for a mass of 8×107M ⊙.Because our spectroscopic targets do not sample the full extent of Leo A,this mass-to-light ratio is a lower limit to Leo A’s true mass-to-light ratio.
A mass-to-light
ratio of 20suggests that Leo A is dom-inated by dark matter.Young &Lo (1996)reach the op-posite conclusion from their H i velocity dispersion,but their result is explained by the revision of Leo A’s dis-tance from 2.2Mpc to 800kpc.Leo A’s total H i mass within a =8′is M HI =1.0±0.2×107M ⊙(Allsopp 1978;Young &Lo 1996)at a distance of 800kpc.The gas mass includes the 10%correction for helium gas.Thus bary-onic matter –stars plus gas –accounts for at most ～20%of Leo A’s total mass.
4.DISCUSSION AND CONCLUSIONS
We have obtained spectroscopy for twelve blue plume objects in the central 2′of Leo A.Ten of these objects are young B supergiants.We measure a stellar velocity dispersion of σ=9.3±1.3km s ?1,identical to Leo A’s H i gas dispersion (Young &Lo 1996).From this we estimate a projected mass of 8±2.7×107M ⊙,which implies that Leo A’s mass is at least ～80%dark matter.Dwarf galaxies are thought to be the smallest bodies containing dynamically signi?cant amounts of dark mat-ter,and so it is interesting to place Leo A in the con-text of cosmological simulations.Evrard et al.(2007)show that the velocity dispersion of dark matter halos follow a tight correlation with total mass,σDM =(1084±13kms ?1)(h (z )M 200/1015M ⊙)0.3359±0.0045,where M 200is the mass within a sphere with mean interior density 200times the critical density.Leo A’s mass,8×107M ⊙,would ?ll such a sphere with a radius of r 200=9kpc.The halo virial relation is derived from ～1015M ⊙dark matter halos,but Evrard et al.show it is valid down to ～1010M ⊙halos.If we simply equate Leo A’s mass to M 200,the halo virial relation predicts σDM =4km s ?1for h (z )=0.70.This prediction is less than half of the observed velocity dispersion.One possible explana-tion for the discrepancy is that Leo A has not reached dynamical equilibrium,and thus its velocity dispersion is in?ated (Young &Lo 1996).Or,perhaps the discrep-ancy suggests that dwarfs like Leo A experience a di?er-ent evolutionary path than a purely hierarchical growth of dark matter halos.
Remarkably,Leo A’s stellar velocity dispersion is very
Fig.5.—Mass-to-light ratio of Local Group dSph galaxies with masses determined from central velocity dispersions (solid squares ),adapted from Mateo (1998)and Koch et al.(2007).The dashed line is the (M/L )tot relation for a galaxy in a dark matter halo of constant mass 3×107M ⊙.We estimate M/L =20±6for Leo A (star ),which falls near the ?xed halo mass relation.The arrow indicates what happens if Leo A stops forming stars and fades to a dSph-like color.The Phoenix transition dwarf (open square )also agrees with the ?xed halo mass relation.
similar to that of Local Group dwarf spheroidals (dSphs),which have central velocity dispersions of 8to 10km s ?1(Mateo 1998).One explanation for the common cen-tral velocity dispersion is that all Local Group dwarfs are enclosed in dark matter halos of similar total mass (Mateo et al.1993).Galaxies with smaller velocity dis-persions (total mass 108M ⊙)are possibly re-ionized and thus never form stars (e.g.Navarro &Steinmetz 1997).If this picture is correct,then the total mass to light ratio of a dwarf is a function of its luminosity (M/L )tot =M DM /L +(M/L )?,where M DM is the ?xed dark matter halo mass,L is the total V -band luminosity,and (M/L )?is the stellar mass to light ratio.
In Figure 5we plot the (M/L )tot versus V -band lu-minosity for Local Group dSphs with central veloc-ity dispersion measurements.We note that Leo A has a central velocity dispersion and no observed ro-tation,thus its dynamical mass is directly compara-ble with dSphs.Dwarf irregulars have masses deter-
Stellar Velocity Dispersion of Leo A5
mined from rotation and are not directly comparable. We base Figure5on the Koch et al.(2007)version of Mateo(1998)’s plot.The solid squares are And II(C?o t′e et al.1999),And IX(Chapman et al.2005), Bo¨o tes(Belokurov et al.2006;Mu?n oz et al.2006),Ca-rina and Sextans(Wilkinson et al.2006),Draco and Ursa Minor(Wilkinson et al.2004),Fornax(Wang et al. 2005),Leo I(Koch et al.2007),Leo II and Sculptor (Mateo1998),and Ursa Major(Willman et al.2005; Kleyna et al.2005).The dashed line shows the(M/L)tot relation for a?xed dark matter halo mass M DM=3×107M⊙and stellar(M/L)?=1.5M⊙/L⊙(Koch et al. 2007).Leo A,plotted as a star,falls very near the?xed halo mass relation for dSphs.
However,Leo A’s stellar population is quite di?erent from that of the dSphs.Integrated colors provide a quan-titative measure of the di?erence:Leo A has(B?V)= 0.15,systematically bluer than the average dSph with (B?V)=0.8±0.25(Mateo1998).As its stellar popula-tion ages,Leo A’s luminosity will decrease and its mass to light ratio will increase.We estimate this change using Starburst99(Leitherer et al.1999;V′a zquez&Leitherer 2005)with Z=0.0004Padova tracks.We?nd that in a couple of Gyr,assuming Leo A has no further star for-mation,it will reach(B?V)=0.8and will have faded ～1.5magnitudes in M V.We indicate this evolution with the arrow in Figure5.Leo A still falls well within the observed scatter around the(M/L)tot relation. Comparing Leo A with“transition dwarfs”may be more fair than comparing with dSphs.Transition dwarfs have old stellar populations like dSphs,but also con-tain gas and young stars like Leo A.A central velocity dispersion is available for the Phoenix transition dwarf (Mateo1998)(the open square in Figure5),which places it squarely on the(M/L)tot relation.Thus,despite their di?erent star formation histories,Leo A,Phoenix,and the dSphs appear to share remarkably similar kinemat-ics and dark matter halo mass.
If transition dwarfs represent the stage between gas-rich dwarf irregulars and gas-poor dSphs,this evolu-tion must involve some amount of galaxy interaction. Most dSphs in the Local Group are located near the ma-jor spirals,so the dSphs’lack of gas and young stars likely results from repeated gravitational and/or hydro-dynamic interactions with the spirals.In a comprehen-sive study of minor galaxy interactions in the SDSS, Freedman Woods&Geller(2007)?nd that the lowest luminosity galaxies in close pairs experience the largest fractional boosts in their speci?c star formation rates. Perhaps Leo A’s episodic star formation history is a his-tory of its interactions with objects in the Local Group. One clue to the evolution of transition dwarfs in the Local Group may come from comparison of the rotation velocity and central velocity dispersion.A wide variety of studies demonstrate the relation between these kinematic measures and the formation history of galaxies(e.g. Pizzella et al.2005;Jesseit et al.2005;de Rijcke et al. 2005;De Rijcke et al.2006).Multi-slit spectrographs can now provide radial velocities for hundreds of stars in nearby dwarfs,making such studies possible for the ?rst time.
We thank K.Rines for helpful discussions and thank the referee for comments that improved this paper.We thank M.Alegria,J.McAfee,and https://www.wendangku.net/doc/9b3281455.html,one for their assistance with observations obtained at the MMT Ob-servatory,a joint facility of the Smithsonian Institution and the University of Arizona.This project made use of data products from the Sloan Digital Sky Survey,which is managed by the Astrophysical Research Consortium for the Participating Institutions.This research made use of the Smithsonian/NASA Astrophysics Data Sys-tem Bibliographic Services.This work was supported in part by W.Brown’s Clay Fellowship and by the Smith-sonian Institution.
Facilities:MMT(Blue Channel Spectrograph)
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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
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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/9b3281455.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/9b3281455.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