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《11规则》题库第二章航海仪器测试题基本信息：[矩阵文本题] *1. ______ is not required by bridge-to-bridge communications. [单选题] *VHFSARTNAVTEXLES(正确答案)2. As for Racon, which one is incorrect in the following? [单选题] *Racon is a radar transponderRacon is often installed on major waypointsWhen activated by a radar signal, the Racon sends it back with an identifier Racon can be used to take place of radar(正确答案)3. PAN-PAN repeated three times over the radiotelephone indicates which type of message will follow? [单选题] *DistressSafetyAll clearUrgency(正确答案)4. Automatic identification systems (AIS) are expected to broadcast all of the following information except ______. [单选题] *port of origin(正确答案)name of vesselcourse and speed over grounddraft of vessel5. What does a navigator who uses an ECDIS require? [单选题] *Good navigational knowledge and a professional job attitude(正确答案)Good computer knowledgeGood system knowledgeNothing special6. The terrestrial system of GMDSS consists of ____________. [单选题] *radio-telephony, DSC, Direct Printing Telegraphy, Navtex and SART(正确答案) INMARSAT, DSC, Direct Printing Telegraphy, Navtex and SARTradio-telephony, DSC, EPIRB, Navtex and SARTStatus Recording system, DSC, Direct Printing Telegraphy, Navtex and SART7. The ______ provides the link between the Space Segment and the land-based National/International fixed communications networks. [单选题] *VHFSARTNAVTEXLES(正确答案)8. If the electronic chart is part of an ECDIS, it must display the minimum data required by IMO/IHO, to include all the following EXCEPT ______. [单选题] *hydrographyaids to navigationtidal current(正确答案)regulatory boundaries9. When a call is complete，and subsequently during an exchange of messages，a station invites a reply by saying ___. [单选题] *“Over”(正确答案)“Out”“OK”“Roger”10. What is the correct speed input to an ARPA used for traffic surveillance? [单选题] *Ground speedSpeed through water(正确答案)Speed from GPSSpeed from Doppler11. All echo-sounders can measure the ______. [单选题] *actual depth of wateractual depth of water below keel(正确答案)average depth from waterline to hard bottomaverage depth of water to soft bottom12. A satellite navigation system with global coverage may be termed as global navigation satellite system or _____. [单选题] *GNSS(正确答案)EPIRBSSASECDIS13. The VDR system is designed to operate_____ once it is set up correctly. There is no user interaction . [单选题] *automatically(正确答案)accuratelypromptlyConspicuously14. What is the MOST important thing you should do before transmitting on a marine radio? [单选题] *Ask for permissionRecord the time in your radio logPress the push to talk button three timeMonitor the channel to ensure that it is clear(正确答案)15. While underway, a vessel over 100,000 gross tons with an automatic identification system (AIS) is expected to broadcast all of the following information every 1 to 10 seconds EXCEPT ______. [单选题] *rate of turnname of the vessel(正确答案)navigational statusship’s heading16. The GPS system was designed for ______ satellites. [单选题] *3121824(正确答案)17. What is important to check when transferring a position from GPS to a chart? [单选题] *Reading the position correctlyPlotting the position correctlyMake sure that the chart and the GPS use same datum(正确答案)Make sure the map is updated18. You are using a radar in which your own ship is shown at the center, and the heading flash always points to 0 degree, If bearings are measured in relation to the flash, what type of bearings are produced? ______. [单选题] *Relative(正确答案)TrueCompassMagnetic19. The compass error of a magnetic compass that has no deviation is ______. [单选题] *zeroequal to variation(正确答案)eliminated by adjusting the compassconstant at any geographical location20. A radar range to a small，charted object such as a light will provide a line of position in the form of ______. [单选题] *straight linearc(正确答案)parabolahyperbola21. You have another ship overtaking you close aboard to starboard. You have 3 radar targets bearing 090，0.5 mile, 1 mile，and 1.5 miles. In this case，the unwanted echoes are called ______. [单选题] *Multiple echoes(正确答案)SpokingIndirect echoesSide-lobe echoes22. What is the main purpose of DGPS? [单选题] *Improve positioning accuracy(正确答案)Decrease positioning accuracyReduce operational costI don't know23. When it is accepted to remain on the frequency indicated，you should say ______. [单选题] *standing by on VHF frequency(正确答案)coming to VHF frequencyVHF frequency is the best place for you to stay byremaining in frequency and do not change24. The satellite systems of GMDSS comprise ______. [单选题] *NAVTEX, COSPAS/SARSAT, EPIRBs and Status Recording-systemInmarsat, COSPAS/SARSAT, EPIRBs and Status Recording-system(正确答案) NAVTEX, Inmarsat, EPIRBs and SARTInmarsat, Direct Printing Telegraphy, and DSC25. When another calling channel/frequency is available，do not use ______ or other safety frequencies to make a transmission. [单选题] *2182 kHz or VHF Channel 16(正确答案)VHF Channel 76FAXCABLES26. How to reduce beam width distortion? [单选题] *Adjust centre positionAdjust brillianceAdjust heading markerReduce gain(正确答案)27. ______ is on the panel of DF. [单选题] *ZERO CLEARING(正确答案)ANTI-CLUTTER-RAINDIMMERCURSOR28. In radiotelephony，the spoken word for distress is ______. [单选题] *SecuriteSafetyEmergencyMAYDAY(正确答案)29. Which one of the followings is incorrect about magnetic compass? [单选题] *The magnetic compass is compulsory on my vesselThe magnetic compass is prone to errorThe magnetic compass is always placed inside steel constructions(正确答案)The magnetic compass needs to be calibrated to compensate for local magnetic distortion 30. Radar reflectors are required for ______. [单选题] *all fishing vessels over 39 feet in lengthsail-propelled fishing vesselsall fishing vessels of less than 200 GTwooden hull fishing vessels with a poor radar echo(正确答案)31. If there were suddenly an immediate danger for both the vessel and its crew, would you send a MAYDAY on__ [单选题] *Ch06 with dual watchCh06 with 25 watts outputCh16 with 1 watt outputCh16 with 25 watts output(正确答案)32. The line connecting the Loran-C master station with a secondary station is called the ______. [单选题] *focus linebase line(正确答案)side linecenter line33. If a GMDSS radio operator initiates a DSC distress transmission but does not insert a message，what happens? [单选题] *The transmission is aborted and an alarm sounds to indicate this data must be provided by the operatorThe transmission is not initiated and “ERROR” is indicated on the display readoutThe transmission will be made with “default” information provided automatically(正确答案)The receiving station will poll the DSC unit of the vessel in distress to download the necessary information34. Ship to ship communications during SAR should be executed by _____. [单选题] * VHFMFSatelliteVHF and MF(正确答案)35. The indicated heading should not be relied on ________. [单选题] *until the gyrocompass has settled(正确答案)until the “Ready” lamp will be litwhen the alarm is generatedwhen the red “Power” lamp RCU illuminates36. When your vessel is proceeding to the area of traffic density，______ is used to determine the exact ranges of other ships or objects in the vicinity. [单选题] * Radar(正确答案)GPSDFSatellite Navigator37. Magnetic heading differs from compass heading by _______. [单选题] * compass errortrue headingvariationdeviation(正确答案)38. What is the primary equipment for receiving MSI ________. [单选题] *SARTEPIRBNAVTEX(正确答案)INMARSAT-B39. If the gyrocompass error is east，what describes the error and the correction to be made to gyrocompass headings to obtain true headings ________. [单选题] *The readings are too low（small numerically）and the amount of the error must be added to the compass to obtain true(正确答案)The readings are too low and the amount of the error must be subtracted from the compass to obtain trueThe readings are too high（large numerically）and the amount of the error must be added to the compass to obtain trueThe readings are too high and the amount of the error must be subtracted from the compass to obtain true40. If the magnetic heading is greater than the compass heading，the deviation is ______. [单选题] *east(正确答案)westnorthsouth41. Deviation which is maximum on intercardinal compass headings may be removed by the ______. [单选题] *Flinders barTransverse magnetsFore-and-aft magnetsSoft iron spheres on the sides of the compass(正确答案)42. The accuracy of the DGPS mainly depends on_______. [单选题] *the price of the equipmentthe relative angle between the satellitethe position of the observerthe age of the calculated correction(正确答案)43. Which statement concerning locating signals in the GMDSS is FALSE? [单选题] *Locating signals are transmitted by survival craft VHF transceivers.(正确答案) Locating signals are transmitted by SARTS.Locating signals are intended to facilitate the finding of a distressed vessel or its survivorsLocating signals are not transmitted by auto alarm generators.44. Coral atolls, or a chain of islands at right angles to the radar beam, may show as a long line rather as an individual targets due to ______. [单选题] *the effects of beam width(正确答案)limitations on range resolutionthe pulse length of the radarthe multiple-target resolution factor45. Quadrantal error in a gyrocompass has its greatest effect ______. [单选题] *in high latitudesnear the equatoron north or south headingson intercardinal headings(正确答案)46. What is important to remember when using AIS for collision avoidance? [单选题] *AIS may not give a complete picture of the traffic situation(正确答案)AIS is more accurate than ARPAAIS is not as accurate as ARPAAIS is not allowed to be used for collision avoidance47. Integrated Bridge and Navigation Systems (IBS/INS) provide excellent performance and reliable navigation under all conditions by _____. [单选题] *integrating well-proven, harmonizing equipment(正确答案)integrating all equipment in the bridgean intelligent platform with ECDIS and Radarthe control center based on ECDIS48. Which statement concerning GPS is TRUE ________. [单选题] *It cannot be used in all parts of the worldThere are 12 functioning GPS satellites at presentIt may be suspended without warning(正确答案)Two position lines are used to give a 2D fix49. When hitting a solid object such as a ship or an airplane, the radar waves are reflected back ______ they came. [单选题] *in the waythe wayby the waythrough the path(正确答案)50. A Doppler log in the volume reverberation mode indicates ______. [单选题] *speed being made goodspeed through the water(正确答案)the set of the currentthe depth of the water51. ECDIS must be able to perform all of the following EXCEPT ______. [单选题] *determine true bearing and distance between two geographical pointsdetermine magnetic compass deviation(正确答案)transform a local datum to the WGS-84 datumconvert “graphical coordinates” to “display coordinates”52. According to SOLAS the breathing air apparatus that must be onboard shall have sufficient capacity for how many minutes of operation? [单选题] *2030(正确答案)456053. Which factor has the greatest effect on the amount of gain required to obtain a fathometer reading? [单选题] *Salinity of waterTemperature of water(正确答案)Atmosphere pressureType of bottom54. Your ARPA has two guard zones. What is the purpose of the inner guard zone? [单选题] *Alert the watch officer that a vessel is approaching the preset CPA limitWarn of small targets that are initially detected closer than the outer guard zone(正确答案)Guard against target loss during critical maneuvering situationsSound an alarm for targets first detected within the zone55. ETA／PILOT REVERTING means [单选题] *ETA pilot station has been givenETA pilot station will be given afterwards(正确答案)ETA pilot station was not givenETA pilot station is given56. ________is used for providing homing signals from survival craft for detection by 9 GHz radar. [单选题] *NAVETEX receiverSearch and Rescue Transponder(正确答案)Emergency Position Indicating Radio BeaconDigital selective calling57. ______ is used for safety of navigation ship-to-ship. [单选题] *Channel 6Channel 13(正确答案)Channel 16Channel 7058. Which action should you take after sending a false distress alert on VHF? [单选题] *Send a DSC cancellation message on Ch-70.Make a voice announcement to cancel the alert on Ch-16.(正确答案)Make a voice announcement to cancel the alert on Ch-13.Make a voice announcement to cancel the alert on Ch-22A.59. ______ typically extends from close as 0.1 nautical miles out to 32 NM. [单选题] *EBLVRMCRTtarget tracking range(正确答案)60. When own ship’s position input to ECDIS is wrong, what is the result? [单选题] *NothingECDIS will give warningECDIS will automatically be switched offPosition, range and bearing taken on the ECDIS will be wrong(正确答案)61. The radar control used to reduce sea return at close ranges is the ______. [单选题] *Gain controlSensitivity time control(正确答案)Fast time constantPulse length control62. The common way to obtain your ship’s position is ______. [单选题] *keeping a close watch and lookouttaking a radar range and bearing(正确答案)observing a radar target and listening to signalskeeping a well clear caution63. A radar display in which North is always at the top of the screen is a（n）______. [单选题] *Unstabilized displayStabilized display(正确答案)Composition displayRelative display64. ______ is a radio receiver with ability to sense direction of the incoming radio waves. [单选题] *The echo sounderThe radarThe course recorderThe direction finder(正确答案)65. The abbreviation RYC in a marine cable generally stands for ______. [单选题] *referring to your crewreference for your captainreturn to your cabinreceived your cable(正确答案)66. How long must the GMDSS radio log be retained on board ________. [单选题] *At least two years after the last entry(正确答案)At least one year after the last entryAt least 90 days after the last entryAt least 30 days after the last entry67. The angular difference between the true meridian（great circle connecting the geographic poles）and the magnetic meridian（direction of the lines of magnetic flux）is called ______. [单选题] *deviationvariation(正确答案)errordifference68. If you receive the signal over radiotelephone of Romeo Papa Tango while using the International Code of Signals, you should ______. [单选题] *report to the callerrepeat your last transmission(正确答案)continue since he received your last transmissionend the transmission69. Deviation changes with a change in ______. [单选题] *latitudeheading(正确答案)longitudesea conditions70. How does current and drift effect the relative motion, relative vector presentation? [单选题] *No effect(正确答案)Producing small errors in calculated aspectProducing large errors in calculated aspectProduce errors in calculated CAP/TCPA71. A single vertical magnet placed underneath the compass in the binnacle is used to compensate for ______. [单选题] *the horizontal component of the permanent magnetismdeviation caused by the vessel's inclination from the vertical(正确答案)induced magnetism in the horizontal soft ironinduced magnetism in the vertical soft iron72. The receiver uses ______ satellites to compute latitude，longitude，altitude，and velocity. [单选题] *onetwothreefour(正确答案)73. ______ is used for calling and replying, and for transmitting acknowledging and relaying distress alerts. [单选题] *NAVTEX receiverSearch and Rescue TransponderEmergency Position Indicating Radio BeaconDigital selective calling(正确答案)74. How is an uncoded racon displayed on the PPI? [单选题] *As a line(正确答案)As a dotAs a small circleAs a large circle75. Variation is a compass error that you ______. [单选题] *can correct by adjusting the compass cardcan correct by adjusting the compensation magnetscan correct by changing the vessel’s headingcannot correct(正确答案)76. Before sailing, mariners on duty shall check the headings of magnetic compass by comparison with _____. [单选题] *ship’s clockengine movement recorderrepeaters(正确答案)navigation lights77. ____ is the navigational timekeeper of the vessel. [单选题] *The marine sextantThe chronometer(正确答案)The magnetic compassThe gyrocompass78. A(n) ______ indicates that there is serious and immediate danger for vessel, crew and passengers. [单选题] *distress alert(正确答案)urgency messagesafety messageroutine message79. Which one of the followings is a standard phrase? [单选题] *WARNING. You are running into danger.(正确答案)You are possibly running into danger.You could be in the case of running into danger.You could , I think , be running into danger.80. What is the right way to use VHF CH16 and working channel? [单选题] *Ships can call other ships on Ch16 but should move to a working channel as soon as possible.(正确答案)Ship should use working channel to call other ships at any time.Ch16 is only used as the international distress and calling frequency.Ship can use Ch16 or working channel as they like81. The ship LRIT system shall transmit the ship’s LRIT information at ______ to an LRIT DATA center ? [单选题] *1-hour interval2-hour interval3-hour interval6-hour intervals(正确答案)82. In ________ within coverage of an Inmarsat geostationary satellite, continuous alerting is available. [单选题] *Sea Area A1Sea Area A2Sea Area A3(正确答案)Sea Area A483. How to report your ship call sign to a shore station? [单选题] *Use capital lettersUse phonetic alphabet(正确答案)Use letters and numbersUse flag signals84. Any piece of metal on becoming magnetized will develop regions of concentrated magnetism called ______. [单选题] *fluxpoles(正确答案)magnetsazimuth85. ____ is used for measuring horizontal and vertical angles. [单选题] *The marine sextant(正确答案)The chronometerThe magnetic compassThe gyrocompass86. Which of the following is defined as static information? [单选题] *Navigational statusSafety related messageMMSI(正确答案)Route plan87. The ______ transmits own ship data cyclically via two defined VHF channels and receives the same data of the other ships and objects that are equipped with AIS systems. [单选题] *AIS(正确答案)ECDISGPSVDR88. What are the only magnetic compass correctors that correct for both permanent and induced effects of magnetism？ [单选题] *Quadrantal spheresHeeling magnets(正确答案)Athwartships magnetsFore-and-aft magnets89. All VHF marine band radios operate in the simplex mode, which means that ______. [单选题] *only one person may talk at a time(正确答案)only two persons may talk at the same timethe radio only transmitsthe radio only receives90. What type of radar can activate a racon? [单选题] *X-band radar(正确答案)S-band radarC-band radarNo radar can91. Your radar is set on a true motion display. Which of the following will NOT appear to move across the PPI scope? [单选题] *Echoes from a buoy(正确答案)Own ship's markerEcho from a ship on the same course at the same speedEcho from a ship on a reciprocal course at the same speed92. What is the spoken emergency signal for a “man overboard” on the VHF radio? [单选题] *Man OverboardSecurityMaydayPan-Pan(正确答案)93. When the transmissions of a radio station have broken down, switched off or suspended, it is _______. [单选题] *unfunctionalbreak downoff poweroff air(正确答案)94. The maritime radio system consisting of a series of coast stations transmitting coastal warning is called______. [单选题] *NAVTEX(正确答案)HYDROLANT/HYDROPACNAVAREASAFESEA95. If a magnetic compass is not affected by any magnetic field other than the Earth's，which statement is TRUE? [单选题] *Compass error and variation are equal(正确答案)Compass north will be true northVariation will equal deviationThere will be no compass error96. Which device provides the main means in the GMDSS for locating ships in distress or their survival craft? [单选题] *Radio direction finderSatellite EPIRBs(正确答案)MF/HF DSCVHF homing device97. The description of RACON beside an illustration on a chart would near a ______. [单选题] *radar conspicuous beaconcircular radiobeaconradar transponder beacon(正确答案)radar calibration beacon98. A navigator fixing a vessel’s position by radar______. [单选题] *should never use radar bearingsshould only use radar bearings when the range exceeds the distance to the horizoncan use radar information from one object to fix the position(正确答案)must use information from targets forward of the beam99. Lines on a chart which connect points of equal magnetic variation are called ______. [单选题] *Magnetic latitudesMagnetic declinationsDipIsogonic lines(正确答案)100. AMVER is a system which provides ______. [单选题] *satellite communicationsnavigational informationweather informationposition reporting service(正确答案)。
T HE A STROPHYSICAL J OURNAL,546:585È603,2001January12001.The American Astronomical Society.All rights reserved.Printed in U.S.A.(SOLAR OSCILLATIONS AND CONVECTION.II.EXCITATION OF RADIAL OSCILLATIONSR.F.S TEINDepartment of Physics and Astronomy,Michigan State University,East Lansing,MI48823;stein=ANDA.N ORDLUNDTheoretical Astrophysics Center and Astronomical Observatory/Niels Bohr Institute for Astronomy,Physics,and Geophysics,Juliane Maries Vej30,Dk-2100Copenhagen Denmark;^,aake=astro.ku.dkReceived1998November4;accepted2000July27ABSTRACTSolar p-mode oscillations are excited by the work of stochastic,nonadiabatic,pressureÑuctuations on the compressive modes.We evaluate the expression for the radial mode excitation rate derived by Nor-dlund&Stein using numerical simulations of near-surface solar convection.WeÐrst apply this expres-sion to the three radial modes of the simulation and obtain good agreement between the predicted excitation rate and the actual mode damping rates as determined from their energies and the widths of their resolved spectral proÐles.These radial simulation modes are essentially the same as the solar modes at the resonant frequencies,where the solar modes have a node at the depth of the bottom of the simula-tion domain.We then apply this expression for the mode excitation rate to the solar modes and obtain excellent agreement with the low l damping rates determined from data obtained by the““global oscil-lations at low frequenciesÏÏ(GOLF)instrument on SOHO.Excitation occurs close to the surface,mainly in the intergranular lanes and near the boundaries of granules(where turbulence and radiative cooling are large).The nonadiabatic pressureÑuctuations near the surface are produced by small instantaneous local imbalances between the divergence of the radiative and convectiveÑuxes near the solar surface.Below the surface,the nonadiabatic pressureÑuctuations are produced primarily by turbulent-pressure Ñuctuations(Reynolds stresses).The frequency dependence of the mode excitation is due to e†ects of the mode structure and the pressureÑuctuation spectrum.Excitation is small at low frequencies because of mode propertiesÈthe mode compression decreases and the mode mass increases at low frequency.Exci-tation is small at high frequencies because of the pressureÑuctuation spectrumÈpressureÑuctuations become small at high frequencies because they are due to convection,which is a long-timescale pheno-menon compared with the dominant p-mode periods.Subject headings:methods:numericalÈSun:granulationÈSun:interiorÈSun:oscillations1.INTRODUCTIONTwo ideas for the source of p-mode excitation have been pursued:overstability(as in pulsating stars)and turbulent Reynolds stresses(as in jet noise)(Biermann1948;Sch-warzschild1948;Lighthill1952;Stein1967,1968;Crighton 1975;Ando&Osaki1977;Goldreich&Keeley1977; Goldreich&Kumar1990;Balmforth1992;Musielak et al. 1994).We show here that it is the PdV work of stochastic, nonadiabatic pressureÑuctuations that is the primary mode excitation mechanism(Stein&Nordlund1991;Bogdan, Cattaneo,&Malagoli1993;Goldreich,Murray,&Kumar 1994).Near the surface,the nonadiabatic gas-pressure(i.e., entropy)Ñuctuations dominate.They are produced by radi-ative cooling at the solar surface,which is not locally and instantaneously exactly balanced by convective heat depo-sition.Below the surface,nonadiabatic turbulent-pressure (Reynolds stress)Ñuctuations dominate.They are produced by the turbulent convective motions.In a previous paper(Nordlund&Stein2000)we derived an exact expression for the stochastic excitation rate of the radial solar p-modes by the PdV work of nonadiabatic gas and turbulent-pressureÑuctuations on the mode compres-sion.We now use realistic numerical simulations of near-surface solar convection(depth about2.5Mm)to evaluate this expression(Stein&Nordlund1998).Because the largest entropy and pressureÑuctuations occur near the solar surface and because modes with frequencies in the3È4 mHz range,where the excitation rate is largest,are conÐnednear the solar surface,these near-surface simulations include the primary excitation and damping processes.2.MODE EXCITATION:FORMALISMThe rate of energy input to the modes can be calculated starting with the kinetic energy equation for the modes (Nordlund&Stein2000).Neglecting the viscous stresses,oDDtA12uz2B\[LL z[uz(Pg]Pt)]]o uzg](Pg]Pt)L uzL z.(1)After integrating this equation over depth,theÑux diver-gence term contributes only at the end points and is negligi-ble.The buoyancy term is small because mass is conserved so there is no net massÑux.The last term is the PdV work,W\PdtPdz d PLmL z.(2)There are several contributions to this work.The displace-ment,m,has contributions from the modes as well as the random convective motions.The pressure,d P,has coherent contributions from the modes and incoherent contributions from the random convective motions.Both coherent and incoherent contributions can be further divided into adia-585586STEIN &NORDLUND Vol.546F IG .1.ÈKinetic energy,horizontally averaged and integrated over depth.Three radial modes are clearly visible.Least squares,Lorentzian,Ðts to the modes,and linear Ðts to the background noise are superimposed.batic and nonadiabatic terms.The dominant driving comes from the interaction of the nonadiabatic,incoherent pres-sure Ñuctuations,d P nad \(d ln P [!1d ln o )P ,(3)with the coherent mode displacement,D ln o Dt \[Lm L z.(4)F IG .2.ÈVelocity eigenmodes of the simulation compared with those ofa solar model (model S of Christensen-Dalsgaard et al.1996).The modes are normalized by the square roots of their energies (eq.[6]).The solar modes that have nodes at the bottom of the simulation domain closely match the simulation modes.The simulation corresponds to thep 1-mode solar and the simulation corresponds to the solar p 16-mode,p 2-mode p 26-Thesimulation lies above the acoustic cuto†frequency.mode.p 3-mode TABLE 1M ODE P ROPERTIESl *l E u !dE /dt (mHz)(k Hz)(ergs)Q (s ~1)(ergs s ~1)2.57......19.0 3.4]1026135 1.2]10~4 4.3]10223.88......133 2.6]1025298.4]10~4 2.2]10225.58......4382.2]1024132.7]10~36.1]1021This is a stochastic process,so the pressure Ñuctuations occur with random phases with respect to the modes.Therefore,one must average over all possible relative phases between them.The resulting rate of energy input to the modes is (Nordlund &Stein 2000)*S E u T *t \u 2o /r dr d P u *(Lm u /L z )o 28*l Eu.(5)Here,is the time Fourier transform of the nonadiabaticd P utotal pressure.*l \1/(total time interval)is the frequency resolution with which is computed.is the moded P u m u displacement eigenfunction,which is typically chosen to bereal for an adiabatic mode.In that case,taking the complex conjugate of the pressure is not necessary,but we retain it for generality.The mode energy isE u \12u 2P rdr om u 2A r R B2\M u V u 2(R ).(6)Here is the mode mass and is the mode velocityM u V u (R )amplitudeat the surface.Equation (5)is similar to theexpression of Goldreich et al.(1994,eq.[26])but involves no approximations.Having the numerical simulation data,we can evaluate this expression exactly without having to make approximations in order to evaluate it analytically.13.SIMULATIONSWe simulate a small portion of the solar photosphere andthe upper layers of the convection zone,a region extending 6]6Mm horizontally and from the temperature minimum at [0.5Mm down to 2.59Mm below the visible surface.We solve the equations of mass,momentum,and energy conservation in the formL ln oL t\[u Æ$ln o [$Æu ,(7)L u L t \[u Æ$u ]g [P o $ln P ]1o $Æp ,(8)L e L t \[u Æ$e [Po$Æu ]Q rad ]Q visc ,(9)where is the viscous stress tensor,is the radiativep Q radheating,and is the viscous dissipation.Q viscWe use a nonstaggered grid of either 1252cells horizon-tally by 82cells vertically or 633cells.The spatial deriv-atives are calculated using third-order splines,and the time advance is a third-order leapfrog scheme (Hyman 1979;Nordlund &Stein 1990).The code is stabilized by a hyper-viscosity that removes short-wavelength noise without damping the longer wavelengths.A large fraction of the internal energy is in the form of ionization energy near the solar surface,so we use a realistic equation of state (including the e†ects of ionization and excitation of hydrogen and other abundant elements and the formation and ionization of molecules).The pressureH 2is found by interpolation in a table of P (ln o ,e )and its derivatives,which is calculated with the Uppsala stellar at-mosphere package (Gustafsson et al.1975).1A detailed description of how eq.(5)is evaluated is given in the Appendix.Its validity is tested by applying it to the three radial modes of the simulation domain (°4).No.1,2001SOLAR OSCILLATIONS AND CONVECTION.II.587F IG .3.ÈLogarithm of kinetic energy as a function of frequency and depth.The three resonant modes of the simulation stand out as maxima in the kinetic energy.A regular,continuous pattern of nodes and antinodes in the kinetic energy exists both at the resonant modes and between them.F IG .4.ÈNonadiabatic pressure spectrum at a depth of 100km.Note that it is featureless even at the frequencies of the simulation modes.Hence,the nonadiabatic pressure is primarily due to random convective processes.Radiative energy exchange is critical in determining the structure of the upper convection zone.Near the surface of the sun,the energy Ñow changes from almost exclusively convective below the surface to radiative above the surface.The interaction between convection and radiation near the solar surface determines what we observe and produces the entropy Ñuctuations that lead to the buoyancy work,which drives the convection.This interaction also gives rise to the nonadiabatic pressure Ñuctuations that excite the p -mode oscillations.Hence,the interaction between convection and radiation is crucial for both the diagnostics and the dynamics of convection.Since the top of the convection zone occurs near the level where the continuum optical depth is unity,neither the optically thin nor the di†usion approximations gives reasonable results.We therefore include three-dimensional,LTE,nongray radiation transfer in our model.We simulate only a small region near the solar surface and must therefore impose boundary conditions inside the convectively unstable region.What happens outside our588STEIN &NORDLUND Vol.546F IG .5.ÈMode mass in the simulation domain and the Sun.Mode mass decreases with increasing frequency because higher frequency modes are more concentrated toward the surface than low-frequency modes.Because the solar modes extend below the bottom of the simulation domain,they have a larger mode mass.Because the simulation domain is shallow,the mode mass becomes nearly constant at low frequency where the eigen-functions become nearly constant within the depth of the simulation.computational domain in principle inÑuences the convec-tive motions inside.However,at the top boundary,the density is very low relative to the rest of the volume and hence whatever happens there has very little inÑuence on the convective motions.At the bottom,the incoming Ñuid is to a very good approximation isentropic and featureless and hence carries little information.The unknown inÑuence of external regions should therefore be small.This assertionF IG .6.ÈRate of stochastic energy input to the simulation modes (squares )compared with the predicted excitation rate (plus signs )from the work of nonadiabatic pressure Ñuctuations on the modes (eq.[5]).The solid line is a running boxcar average and the dashed line a two power law Ðt over the entire frequency range.The excitation rate is larger than the solar case because the mass of the modes in the simulation is less than the mass of the modes in the Sun.The near constancy of simulation mode mass at low frequency leads to a much slower decrease of excitation with decreasing frequency than occurs in the Sun.F IG .7.ÈRate of stochastic energy input to modes for the entire solar surface (simulation \triangles ,observations \squares )from Roca Cortes (1999),based on observed mode velocity amplitudes and line widths from global oscillations at low frequencies (GOLF),the instrument on SOHO,for modes with l \0È3,which are all nearly radial close to the surface.The rate of energy input to the solar modes is smaller than to the simulation modes by the ratio of the mode mass of the solar modes to the mode mass in the simulation domain (Fig.5).is indeed conÐrmed by experiments with boundaries located at di†erent depths.The horizontal directions are taken to be periodic.In the vertical direction,we have a transmitting boundary at the temperature minimum (Nordlund &Stein 1990).This is achieved by a larger than normal zone at the top boundary.Across this zone we make the vertical derivative of the density hydrostatic,set the vertical derivative of the velocity to zero,and hold the internal energy at the top Ðducial layer constant in time and space.At the bottom of the computa-F IG .8.ÈThe mode factor in the work integral:Excita-(Lm u /L z )/E u 1@2.tion decreases at low frequency because of mode behavior,in part because the radial wave vector is approximately k \u 2/g and in part because the mode mass increases with decreasing frequency (Fig.5).No.1,2001SOLAR OSCILLATIONS AND CONVECTION.II.589F IG .9.ÈSpectrum of pressure Ñuctuations at a depth of 200km,smoothed with a running boxcar mean.The nonadiabatic gas-pressure Ñuctuations exceed the nonadiabatic turbulent-pressure Ñuctuations by about a factor of 4,but they become comparable in the peak driving range at larger depths.The local maxima in the total pressure Ñuctuations at 2.6,3.9,and 5.5mHz are due to the resonant modes in the simulation.The nonadiabatic pressure varies smoothly across these resonant frequencies,indicating that it is primarily due to convection.The pressure Ñuctuation power decreases roughly as l ~4at high frequency because it is due to stochastic convective motions,which decrease in power at high frequency.tional domain,outgoing Ñuid goes out with whatever properties it has.For incoming Ñuid,we adjust the pressure such that the net mass Ñux through the bottom boundary vanishes.(This ensures that there is no boundary work doneF IG .10.ÈCorrelation of turbulent and gas pressure at the surface.The turbulent pressure is only about 1/6the magnitude of the gas pressure near the surface,but the magnitudes of their Ñuctuations are similar.F IG .11.ÈIntegrand of the work integral,(eq.u 2o d P u *(Lm u /L z )o 2/8*l E u[5]),at 2,3,4,and 5mHz as a function of depth.At frequencies where the driving is large,the integrand is signiÐcant only within 500km of the surface.on vertical oscillation modes.)The pressure on the bottom boundary thus varies in time but is uniform over the hori-zontal plane.We damp Ñuctuations of the horizontal and vertical velocity of the incoming Ñuid,using a long time constant.Finally,we adjust the density and energy of the incoming Ñuid,at constant pressure,to Ðx its entropy (in both space and time).The ability to do a direct numerical simulation with the wide range of length scales matching the dimensionless pa-rametersÈReynolds number,Rayleigh number,and Prandtl numberÈof the solar convection zone is beyond the speed and memory capabilities of current computers.Thus,our simulations are of the type called ““large eddy simulations.ÏÏIt is,however,possible to resolve the surface thermal boundary layer of the convection zone,and this we have done.Indeed,this is required to achieve results that agree quantitatively with solar observations (Stein &Nor-dlund 2000).The picture of convection that has emerged from the simulations is the following.Convection is driven by radi-ative cooling in the thin thermal boundary layer at the solar surface.It consists of cool,low-entropy,Ðlamentary,turbu-lent downdrafts that plunge through a warm,entropy-neutral,smooth,diverging,laminar upÑow.UpÑows must diverge as they ascend into lower density layers in order to conserve mass.This divergence smooths out any variations in their properties that might arise.Only a small fraction of the Ñuid at depth reaches the surface to be cooled and form the cores of the downdrafts.Most Ñuid turns over within a scale height and is entrained by the downdrafts.These low-entropy downÑows are the sites of most of the buoyancy work that drives the convection (see Stein &Nordlund 1998for more details.)We have made numerous comparisons between the pre-dictions of the simulations and solar observations.The depth of the convection zone depends on the opa-cities that determine the temperature versus pressure (and hence entropy)stratiÐcation of the surface layers,the spec-tral line blocking,the convective efficiency of the super-adiabatic layers immediately below the surface that determines the transition to the asymptotic adiabat,and the590STEIN &NORDLUND Vol.546F IG .12.ÈLogarithm (base 10)of the work integrand,(eq.[5];in units of ergs cm ~2s ~1),as a function of depth and frequency.u 2o d P u *(Lm u /L z )o 2/8*l E u The work is concentrated close to the surface in the peak excitation range (3È4mHz)and at higher frequencies.equation of state that determines the further run of tem-perature versus pressure through the convection zone.Excellent agreement is obtained between the depth of the convection zone predicted by our numerical simulations and that inferred from helioseismology (Rosenthal et al.1999).The cavity for high-frequency modes is enlarged by turbulent-pressure support and three-dimensional nonlin-ear opacity e†ects,which increase the average temperature required to produce a given e†ective temperature in an inhomogeneous compared with a homogeneous atmo-sphere.The p -mode eigenfrequencies calculated from the mean simulation atmosphere are signiÐcantly closer to the observed mode frequencies than those for standard spher-ically symmetric,mixing-length models (Rosenthal et al.1998,1999).The simulation granulation size spectrum and the dis-tribution of emergent intensities,when smoothed by the point-spread function appropriate for the Swedish Vacuum Solar Telescope on La Palma (which produces the best solar images available today),closely match the obser-vations (Stein &Nordlund 1998).The width of photospheric iron lines (whose thermal speed is small)is a signature of the convective velocities.The net Doppler blue shift and asymmetry of spectral lines is a signature of the correlation between velocity and tem-perature Ñuctuations.Both these signatures agree closely with observations (Asplund et al.2000).F IG .13.ÈCorrelation of nonadiabatic pressure with vertical velocity at the surface.The large negative Ñuctuations in the nonadiabatic pressure occur where the velocity is positive (downward)in the intergranular lanes.No.1,2001SOLAR OSCILLATIONS AND CONVECTION.II.591F IG .14.ÈImage of the nonadiabatic total pressure Ñuctuations at depth 100km,with the contours of zero surface velocity to outline the granules.The units of the pressure are 103dynes cm ~rge,negative pressure Ñuctuations occur in the intergranular lanes.Positive pressure Ñuctuations are one-half as large and occur inside the granules.This gives us conÐdence that the simulations are properly modeling the crucial properties of near-surface solar con-vection.4.MODE EXCITATION :SIMULATIONThree radial modes exist in our simulation,and we Ðrst apply equation (5)to these modes and compare the rate of work on the modes it predicts with the actual excitation rate determined from the modeÏs energies and dE u /dt \!E u widthsin the simulation.The modes can be clearly seen in the spectrum of the horizontally averaged,depth-integrated kinetic energy (Fig.1).Their properties are given in Table 1.The lowest mode (with no zero crossings inside the compu-tational domain)has a frequency of 2.57mHz and an FWHM of 19k Hz.Hence,a simulation signiÐcantly longer than 14.5hr is required to resolve this mode.We use a simulation of 43hr,with a spatial resolution of 633.Snap-shots were saved at 30s intervals.The eigenfunctions of the velocity are calculated by taking the time Fourier transform of the velocity.To get thereal eigenmode,the transform of the velocity at the fre-quency of the mode is divided by its most common phase among all depths.To reduce the noise,we average the result over a frequency band,approximately equal to the FWHM of the mode,centered on the mode.The eigenfunctions are essentially the same as the solar model modes of Christensen-Dalsgaard using his spherically symmetric model S (Christensen-Dalsgaard et al.1996)at the mode frequencies (Fig.2),when the modes are normalized by the square root of the mode energy,or,which is equivalent,by their amplitude at the surface.Hence,we choose to use the solar model eigenfunctions because they are much denser (35radial modes below the acoustic cuto†frequency instead of three)and because they are slightly smoother.Another way of looking at the modes is via their kinetic energy.Figure 3is an image of the logarithm of the kinetic energy as a function of depth and frequency.The three modes of the computational domain are clearly seen.Notice also that there is a continuous pattern of nodes and antinodes,with the nodes descending in depth as the frequency increases592STEIN &NORDLUND Vol.546F IG .15.ÈImage of nonadiabatic pressure Ñuctuations at 100km depth in the 2È5mHz range,with the contours of zero velocity at the surface to outline the granules.The units of the pressure Ñuctuations are 103dyne cm ~2.In this frequency range,where the driving is maximal,the largest occur at thed P nad edges of granules and inside the intergranular lanes.and new nodes starting at the surface.This pattern extendseven into the propagating region above the acoustic cuto†frequency of about 5.3mHz.The actual mode energy decay rate of the simulation modes,which on average is equal to their excitation rate,is obtained by multiplying the energy of each mode by its decay rate which is its radian line width and!\2n*l FWHM,is obtained from the Ðt to the modes (Fig.1).The total mode energy is the sum of the mode energies minus a Ðt to the background over the frequency range where the modes are signiÐcantly above the background multiplied by the area (36Mm 2)of the simulation domain (Fig.1).Equation (5)is used to predict the mode excitation rate.The nonadiabatic total (gas ]turbulent)pressure Ñuctua-tions are calculated directly from the simulation by Ðrst averaging the gas pressure,turbulent pressure,and density over horizontal planes at each saved snapshot.These are then interpolated to the Lagrangian frame at each time.The nonadiabatic pressure Ñuctuations are calculated as in equations (A1)and (A2).The oscillation modes of the domain are essentially adiabatic and do not a†ect the non-adiabatic pressure Ñuctuations as can be seen from its fea-tureless,noisy spectrum (Fig.4).Thus,the nonadiabatic pressure work is due primarily to the convection.The mode compression is calculated from the Christensen-Dalsgaard modes (since these are essentially identical with the simulation modes at the resonant frequencies)normalized by the square root of their energy in the simulation domain.Because the simulation domain is shallow while,especially at low frequency,the solar modes have substantial amplitude below the computational domain,the mode mass in the computational box is signiÐ-cantly smaller than the actual mode mass of the solar modes (Fig.5).Finally,we compare the actual mode energy decay rate with the predicted rate of work by convection on the modes given by equation (5)in Figure 6.The squares are the actual mode energy decay rates for the three resonant modes of the box.The solid line is the running mean of the predictedNo.1,2001SOLAR OSCILLATIONS AND CONVECTION.II.593F IG .16.ÈRate of stochastic energy input to modes for the entire solar surface,showing the individual contributions of the nonadiabatic gas and turbulent pressure to the work of the total nonadiabatic pressure.Most of the driving in the peak driving range comes from the turbulent pressure.work,and the dashed line is a smooth two power law Ðt to the predicted work.The agreement is very good,but not perfect.There are signiÐcant deviations from the power-law Ðt in the neighborhood of the modes,and these are reÑected in the actual mode decay rate.This is a phenomenon that still remains to be explained.Notice also that the decrease in work toward low frequencies is much slower than for the Sun (Fig.7).The reason is the near constancy of the mode mass within the simulation domain at these low frequencies compared with the steeply rising mode mass with decreas-ing frequency on the Sun.This application of our excitationF IG .17.ÈMode driving at 4mHz evaluated from the surface to depth z ,showing the individual contributions of the nonadiabatic gas and turbu-lent pressure.Close to the surface the contributions of the two are compa-rable,but there is little contribution from the gas pressure below 200km depth,while the turbulent-pressure work is signiÐcant down to 500km depth.F IG .18.ÈHorizontally averaged nonadiabatic pressure at the surface and emergent intensity variation in time.They are tightly correlated,indi-cating that radiative cooling at the surface is the source of the nonadiabatic pressure Ñuctuations there.rate formula to the modes that are excited in our simulation veriÐes that the formula is correct and can be applied to the Sun.5.MODE EXCITATION :SUN5.1.Excitation SpectrumThe excitation rate for solar modes as a function of fre-quency is shown in Figure 7.To obtain these results we used the shorter but higher resolution 1252]82simulation because it has more high-frequency power.The magnitude and frequency dependence we Ðnd for our 6Mm square boxF IG .19.ÈDivergence of the convective and radiative Ñuxes,at z \100km,multiplied by compared with the time derivative of the non-(!3[1)adiabatic pressure at the surface.The units are 103ergs cm ~3s ~1.The rate of change of nonadiabatic pressure closely follows the divergence of the net Ñux but has a slightly larger amplitude.594STEIN &NORDLUND Vol.546F IG .20.ÈCorrelation of the divergence of the convective and radiative Ñuxes,at z \100km,multiplied by with the time derivative of(!3[1)the nonadiabatic pressure at the surface.The units are 103ergs cm ~3s ~1.The close correlation shows that the slight instantaneous imbalance in the radiative and convective Ñux divergences is the primary source of non-adiabatic pressure Ñuctuations.is very close to the observed values for the entire sun.This means that the pressure Ñuctuations must be uncorrelated on larger scales,so there is no extra driving contribution.What produces this frequency dependence?The low-frequency behavior is controlled by the nature of the eigen-modes,and the high-frequency behavior is controlled by the nature of convection.The work integral (eq.[5])contains a factor pertaining to the modes:the radial gradient of the mode displacement normalized by the square root of the mode energy (which makes it independent of the mode amplitude).This is small at low frequencies and increases with frequency approximately as l 3.5(Fig.8).Part of this dependence is due to the radial gradient of the displace-ment.The mode dispersion relation is u \(gk )1@2,so k \u 2/g ,which accounts for two powers of the frequency.The remainder of the frequency dependence is due to the mode mass,which decreases with increasing frequency because higher frequency modes are more concentrated toward the surface (Fig.5).The mode excitation decreases at high frequency because the pressure Ñuctuation power decreases with increasing frequency roughly as l ~4(Fig.9).Convective motions,whose power decreases at small scales and high frequencies,produce the gas and turbulent-pressure Ñuctuations.This then leads to a similar high-frequency decline in the pres-sure spectrum.Total pressure Ñuctuations are small at low frequency because the atmosphere is nearly in hydrostatic equi-librium.However,the turbulent-pressure Ñuctuations are largest at low frequency because they are a convective e†ect and convection is a longer timescale phenomena.Hence,the gas-pressure Ñuctuations must also be large and out of phase with the turbulent-pressure Ñuctuations at low fre-quency in order to produce small total pressure Ñuctuations(Fig.10).The turbulent pressure is small compared with the gas pressure (D 15%),but the magnitudes of Ñuctuations are comparable for the gas and turbulent pressures,so they can indeed cancel each other.5.2.Excitation L ocationAt what depth does the driving occur?Consider the inte-grand of the work integral at di†erent frequencies (Figs.11and 12).At low frequencies the integrand amplitude is similar over an extended depth range,but it is small.Where the integrand is large,in the region of peak driving around 3È4mHz,the integrand becomes concentrated very close to the surface and most driving occurs between the surface and 500km depth.At still higher frequencies the integrand becomes small again and even more concentrated near the surface.Where in space does this driving occur?The warm gran-ules have only small nonadiabatic pressure Ñrge,negative Ñuctuations are concentrated in the down-drafts (Figs.13and 14).The maximum mode driving occurs in the frequency range of 3È4mHz,by nonadiabatic pressure Ñuctuations in the same frequency range.By Ðltering the time sequence of these Ñuctuations we see (Fig.15)that in the peak driving range also the driving occurs predominantly in the inter-granule lanes and near the edges of granules.The high-frequency power near granule edges is due to the motion of the granule boundaries over the 1hr time interval on which the Ðltering was performed.This is,in part,a result of changes in granule size as they evolve.No direct correlation of nonadiabatic pressure Ñuctuations in the range of 2È5mHz with velocity is seen.Keep in mind,however,that a correlation plot does not reveal correlations of events that happen in the neighborhood of one another.5.3.Excitation SourceWhat is the source of the nonadiabatic pressure Ñuctua-tions?Is it entropy Ñuctuations or Reynolds stresses?Both play a role,but the primary source of mode driving is turbulent-pressure Ñuctuations (Reynolds stresses;Fig.16).This is surprising,since the nonadiabatic gas-pressure power is larger than the turbulent-pressure power near the surface (Fig.9).The nonadiabatic gas and turbulent pres-sures contribute comparably to the work near the surface,but the contribution of the turbulent pressure extends deeper and provides the dominant contribution to the total work (Fig.17).The gas-pressure Ñuctuations are signiÐcantly larger than the turbulent-pressure Ñuctuations and have maxima at the frequencies of the three radial modes of the simulation.The nonadiabatic pressure Ñuctuation power,however,varies smoothly across these frequencies,indicating that it is pri-marily due to stochastic convective processes (Fig.9).There is a tight correlation between the nonadiabatic pressure Ñuctuations at the surface and the emergent inten-sity (Fig.18),which indicates that it is the Ñuctuating cooling at the surface that is the main source of stochastic mode excitation there.Indeed,the source of entropy Ñuc-tuations is the cooling of Ñuid that approaches optical depth unity (Stein &Nordlund 1998).This correlated noise is believed to be responsible for the di†erence in asymmetry of the modal power spectra observed in velocity and inten-sity (Nigam et al.1998;Kumar &Basu 1999).Our dis-。
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辐[射]反射比radiant transmittance 辐[射]透射比radiating capacity 辐射本领radiating cone 辐射锥radiating layer 辐射层radiating mirror 辐射瞻射镜radiation (1)辐射(2)放射(3)辐射能radiation cascade 辐射串级radiation damping 辐射阻尼radiation density 辐射密度radiation detector 辐射探测器radiation dose 辐射剂量radiation dosimetry 辐射剂量测定法，辐射剂量测量学radiation excitation 辐射激发radiation factor 辐射系数，辐射因数radiation field 辐射场radiation filter 辐射滤光片radiation image pickup tube 辐射图像摄像管radiation loss 辐射损失radiation measuring instrument 辐射测量仪器radiation meter 辐射[强度]仪器，辐射[强度]计radiation monitoring 辐射监控，辐射检查radiation pattern 辐射高温计radiation peak 辐射巅值radiation power 辐射功率radiation pyrometer 辐射高温计radiation source 放射线radiation sources 热幅光源radiation spectrum 辐射光谱radiation temperature 辐射温度radiation thermometers 热辐射温度感测器radiation thermometry 辐射差电堆radiation transfer 辐射传递radiation transition 辐射跃迁radiation trapping 辐射俘获radiation width 辐射宽度radiation-monitoring film 辐射监控软片radiation-noise-limited system 辐射噪声限制系统radiation-resistant 防辐射的，耐辐射的radiation-resistant glass 防辐射屏蔽radiationless decay 无辐射衰减radiationless resonance 无辐射共振radiationless transition 无辐射跃迁radiative (1)辐射的(2)发射的radiator (1)辐射体(2)辐射器(3)散热器，散热片radical (1)根的(2)根号radication 开方radio (1)无线电的(2)收音机(3)射电，射频的radio astronomy 射电天文[学]radio brightness 射电亮度radio dish 射电抛物面天线radio optics 无线电光学radio receiver 无线电接收机radio telescope 射电望远镜radio wave 无线电波radio-acoustic ranging 电声测距法radio-frequency beat (1)射频(2)拍频radio-frequency coupling technique 射频耦合技术radio-frequency emission 射频发射radio-frequency excited ion laser 射频激发离子激光器radio-frequency holography 射频全息照相术radio-frequency lamp 射频灯radio-frequency pumped 射频抽运的radio-frequency spectroscopy 射频频谱学radio-frequency (R.F.)射频radio-micrometer 辐射微热计radio-shielded 防高频感应的radio-spectrum 射频频谱radio-wave maser 无线电波激射器radio-wave reflection 无线电波反射radioactive 放射性的radioactive atom 放射性原子radioactive counter 放射性计数器radioactive decay 放射性衰变radioactive detector 放射性检测器radioactive half-life 放射性半衰期radioactive isotope 放射性同位素radioactive luminescent paint 放射性发光涂料radioactive metal 放射性金属radioactive source 放射源radioactive tracer 放射性示踪剂radioactivity 放射性radioautogram 自动射线照片radioautograph 自动射线照相，放射线映像，射线显迹图radioautography 自动射线照相术radiochromatogram 辐射色谱图radiochromatograph 辐射色谱图radiochromatography 辐射色谱法，辐射色谱学radiochrometer 射线硬度测定仪radiocrystallography 辐射性结晶体学radioelectronics 无线电电子学Radiofrequency electrosurgical cautery apparatus 射频电烧灼器具radiogram 射线照片radiograph 射线照片radiographic film 射线照相胶片radiography 射线照相术radioheliograph 射电日像仪radiointerferometer 无线电干涉仪radioisotope 放射性同位素radioisotope detector 放射性同位素探测器radioisotopic tracer 放射性同位素指示剂radiology 放射学radioluminescence 辐射发光radiometer 辐射计radiometer package 辐射计装置radiometer telescope 辐射计式望远镜radiometric 辐射度的radiometric detector 辐射度探测器radiometric mapper 辐射度测绘仪radiometric measurement 辐射测量radiometric photometry 辐射测量光度学radiometric quantities 辐射度[物理]量radiometric reading 辐射测量读数radiometric system 辐射测量系统radiometric unit 辐射度单位radiometry 辐射度学，辐射测量[法] radiophoto 无线电照片传真radiophotography 无线电传真术radiophotoluminescence 辐射光致发光radiophotostimulation 辐射光刺激radioscope 放射镜radiosonde 无线电采空仪radiospectroscopy 辐射光谱学radiotelemetric 无线电遥测的radiotheraphyh 放射线疗法radiothermoluminescence 辐射热致发光radius gauge 半径（量）规radius of curvature 曲率半径radius of gyration 旋转半径radius tool 半径工具（曲模）radius vector 向量径radius (复数:radii)半径radix （复数：radices）基数radlux 辐射勒克司radome 天线罩rail 轨（条）rain return 雨水反射raised bell jar 升降钟罩raised face 击面rake 倾斜（度）ralt cake glass 硫酸盐玻璃ram airbreathing laser 速压吸气式激光器Raman diffusion 喇曼散射Raman effect 喇曼效应Raman laser 喇曼激光器Raman liquid laser 喇曼液体激光器Raman mixing 喇曼混频Raman pumping 喇曼抽运Raman scattering laser radar 喇曼散射激光雷达Raman shift laser 喇曼频移激光器Raman shifting 喇曼频移Raman spectrophotometer 喇曼分光光度计Raman spectroscopy 喇曼光谱学Raman spectrum 喇曼光谱Raman transition 喇曼跃迁Raman-Nath diffraction 喇曼乃斯衍射Raman-scattering 喇曼散射Raman-Stokes generation 喇曼-斯托克斯振荡Raman-type scattering 喇曼式散射ramp（1）发射装置（2）倾斜装置Ramsauer effect 冉邵尔效应Ramsauer's circle 冉斯登图Ramsauer's disk (disc)冉斯登班Ramsden's eyepiece 冉斯登目镜Ramsey fringe 冉赛条纹random（1）随机（2）无视random access 随机存取random colo[u]r 任意色random diffuser 无规漫射体random emission 无规发射random error 随机误差random event 随机事件random function 随机函数random interval 随机区间random Moire fringe 无规模阿干涉条纹random noise 无规噪声random optical access 随机光信息存取random path fluctuation 无规光路起伏random phase 随机相位random phase shift 随机相移random process 随机过程random sampling 随机抽样random scattering 无规散射random special phase modulation 无规空间相位调制random variable 随机变量random-access memory 随机存取储存random-access time 随机存取时间random-walk 无规则运动randomization 随机化randomizing effect 随机效应randomly fluctuating plasmas 无规起伏等离子体randomly medium 无规媒质randomly spaced phased array 无规间距相控阵randomness (1)无规性(2)随机性rang-finding lidar systems 距离测定用雷射雷达range (1)范围，区域(2)量程(3)距离range accuracy 测距精度，距离精度range adjustment 量程调整range amplifier 测距放大器range compensator 距离补偿器range finder 测距仪range gated detection 距离选通探测range instrumentation 测距仪range laser radar 激光测距雷达range of exposure (1)曝露范围(2)曝光范围range of ocular accommodation 目镜调节范围range of response (1)视场（光学仪器）(2)响应范围range of telescope 望远镜视场range of video 视频范围range of visibility 视距，能见距离range of vision 视野，视界range resolution 距离分辨率range scope 距离指示器range-finder camera 测距照相机range-finder scope 测距仪瞄准镜range-finder window 测距窗range-finding 测距range-gated imaging technique 距离选通成像技术range-gated laser 距离选通激光器range-to-go 到目标的距离rangefinders 测距仪rangepole 标杆ranger 测距仪ranging 测距ranging laser 测距离激光器ranging theodolite 测距径纬仪ranging unit 测距计rank (1)列，排(2)等级(3)顺序ranked data 分级资料，分级数据Rankin temperature scale 阑金温标（用华氏度数表示的绝对温标）rapid inversion method 快速反转法rapid lens (1)快速透镜(2)大孔径物镜rapid neutron 快速中子rapid orientation 快速定向rapid rectilinear lens (1)快速消畸变镜头(2)快速直线透镜rapid shutter 快速快门rapid-access storage 快速[存取]存储[器]rapid-decay phosphor 短余辉磷光体，快速衰减磷光体rapid-scan spectrometer 快速扫描分光计rare earth element 稀土元素rare earth liquid laser 稀土元素液体激光器rare earth materials 稀土族材料rare earth oxide 稀土氧化物rare earths 稀土rare gas 稀有气体rare gas eximer 稀有气体激光元rare gas laser 稀有气体激光器rare-earth glass 稀土玻璃rare-earth ion 稀土离子rare-earth ion-doped nonlinear crystal 掺稀土离子非线性晶体rare-earth laser 稀土元素激光器rare-earth-doped calcium fluoride 掺稀土氟化钙rare-earth-doped crystal 掺稀土晶体rarefied gas 稀薄气体raster (1)网路(2)光栅（电视）raster grating 网路光栅raster line 网线raster microscope 网格显微镜raster pattern 光栅图样raster-scanned image 光栅扫描图像rat's nest type bolometer 鼠巢式测辐射热计ratchet pawl 棘轮爪ratchet wheel 棘轮ratch[et] (1)棘轮，棘轮机构(2)棘爪rate (1)速率(2)速度rate equation 速率方程rate of incidence 入射率rate of scanning 扫描频率rate of turn gyroscope 回转仪转动速率，陀螺仪转动速率rate-dependent character of corrosion [玻璃]腐蚀速度特性rated power 额定功率rated value 额定值ratemeter 速率计rating (1)额定值(2)分等ratio (1)比，比率(2)比例(3)系数ratio of speed 速比ratiomethod of Fourier spectrometry 傅里叶光谱测量比例法rational system of units 有理单位制rationalization 有理化rationalized unit 合理单位raw (1)原始的(2)未加工的raw data 原始数据raw film 原胶片raw glass 毛坯玻璃raw material 原料ray (1)光线(2)射线ray aberration 光行差ray curvature 射线曲率ray envelop 光束包络，射线包迹ray filter 滤光镜ray of light 光线ray plot 光线[行程]图ray plotter 光绚绘迹器ray trajectory 光线径迹ray velocity 光速rayleigh (R)瑞利（光强度单位，等於106量子∕厘米2）Rayleigh criterion for resolution 瑞利分辨率判据Rayleigh cross-section 瑞利[散射]截面Rayleigh disk 瑞利斑，瑞利盒Rayleigh interferometer 瑞利干涉仪Rayleigh limit 瑞利[分辨]极限Rayleigh quarter-wave limit 瑞四分之一波长极限（瑞利准则）Rayleigh quarter-wave tolerance 瑞利四分之一波长[光学]公差Rayleigh resolution limit 瑞利分辨极限Rayleigh scatter 瑞利散射器Rayleigh spectrometer 瑞利分光计Rayleigh wave 瑞利波Rayleigh's law 瑞利定律Rayleigh-jeans law 瑞利–吉恩斯定律Rayleigh-Ritz variational procedure 瑞利–里兹变分法Rayleigh-Sommerfeld formulation 瑞利–索末菲理论Rayleigh-wing scattering 瑞利翼状散射raytracing device 光线跟踪装置re-centralizing 重定中心re-emission 再发射re-entering 次级射入（粒子由於散射而进入计数器）re-lighting 再次起动，重复起动reactance 电抭reactant (1)反应物(2)反应体(3)反应剂reaction (1)反作用(2)反应reaction force 反作用力reaction principle 反作用原理reaction thrust 反推力reactivation 再激活reactive element 电抗元件reactive power 无功功率reactive sputtering 往复溅射reactivity 反应性reactor (1)反应堆(2)电抗器(3)反应器read head 读[出]头read only memory (ROM)只读存储器，唯读存储器read write memory 读写存储器read-out system 读出系统read-out time 读出时间readability 读出能力reader for microfilm 缩微胶片阅读器reader light 读出器指示灯reading 读数，示数reading accuracy 读出精度reading brush 读孔刷reading certainty 读数确定度reading circuit 读出电路reading device 示读装置，读数装置reading error 读数误差reading glass 阅读放大镜，读数放大镜reading microscope 读数显微镜reading optical beam 读出光束reading telescope 读数望远镜reading value per division of dial disk 刻度盒每格读数值reading value per division of vernier 游标每格读数值reading wand 读数杆readjustment 重[新]调[整]，重校readout 读出readout signal flow 读出信号流readr (1)读出器(2)读数器reagent (1)试剂(2)反应物reagent grade 试剂等级reaging 反复老化real 实的，真实的real aperture 实际孔径，有效孔径real axis 实轴real brightness 真亮度real component 实份量real field 实场real focus 实焦点real gas 真实气体real image 实像real imaginary hologram pair 虚实全息图对real number 实数real object 实物real quantity 实数real space 实物空间，物方real time interferometer 实时干涉仪real time visual reconstruction 实时视觉再现real transition 实跃迁real-time 实时real-time coding 实时编码real-time control system 实时控制系统real-time correction 实时校正real-time Doppler imaging system 实时多普勒成像系统real-time extrapolation 实时外推法real-time filter 实时波器real-time fringe 实时条纹real-time grey level display 实时灰阶显示real-time hologram 实时全息图real-time holography 实时全息术real-time interferometry 实时干涉量度学real-time laser link 实时激光线路real-time linear detection system 实时线性谱观察real-time operation 实时工作real-time optical correlation 实时光学相关real-time optical singnal processor 实时光学信号处理器real-time output 实时输出信号real-time photography 实时摄影术real-time recording 实时记录real-time spectrum analyzer 实时频谱分析器real-valued intensity 实数值场强度reality 真实性realizability 现实性，可实现性realm 领域，范围realuminizing 再镀铝reamer (1)铰刀(2)铰床reaming 铰孔rear (1)後部，背面(2)後面的，背面的rear finder (1)後部描准器(2)後部指示器rear focus 後焦点rear nodal point 後节点rear node 後节点rear operating aperture 後工作孔径rear view 後视图rear-silvered mirror 背面镀银反射镜rear-vision mirror 後视镜reasonable value 合理值reassembly 重装配rebatron 大功率电子聚束器rebound 跳回，弹回recalescence point 复辉点recalibration 重校[准]recasting 重铸receiver 光接收器receiver ,Rx 光接收器receiving aperture 接收孔径receiving objective 接收物镜receiving optics 接收光学系统receiving set 接收机，接收器receiving station 接收站receptacle (1)容器(2)插座，插孔receptacles 插座receptance 敏感性receptor 接收器recess (1)槽，环槽，凹槽(2)切口，凹口recessing 开[凹]槽recipient 信息接收器reciprocal (1)倒易的(2)倒数reciprocal dispersive power 色散率倒数reciprocal ellipsoid 倒易椭球reciprocal equation 倒易方程reciprocal lattice 倒易点阵reciprocal leveling 对向水准测量reciprocal lifetime 寿命倒数reciprocal transducer 倒易换能器reciprocal translation theorem 相互转换定理reciprocal value 倒数值reciprocating movement 往复运动reciprocation 往复，往返reciprocity 倒易性，可逆性reciprocity failure 倒易性失效reciprocity law 倒易律recloser (1)自动开关(2)复合继电器(3)自动复充电装置recognizer 识别器，识别机recoil 反冲，跳回recoil effect 反冲效应recoil electron 反冲电子recoil energy 反冲能量recoil impulse 反冲脉冲recoil shift 反冲漂移recollimation 再准直recombination (1)复合(2)再化合recombination center 复合中心recombination coefficient 复合系数recombination laser 复合激光器recombination lifetime 复合寿命recombination radiation 复合辐射recombination rate 复合率recombination region 复合范围，复合区域recombination time 复合时间recombiner (1)复合器(2)复合剂recon device 侦察装置reconfigurable 重新组态reconnaissance camera 侦察照相机reconnaissance device 侦察仪器reconnaissance equipment 侦察设备reconstructed image 重现象reconstructing hologram 再现全息图reconstructing wave 再现波reconstruction beam 再现光束record (1)记录(2)录声(3)录象record chart 记录卡，记录[图]表record circuit 记录电路recordability 可记录性recorder (1)记录器(2)录声机recorder deflection 记录器偏转recorder scan 记录器扫描recorder-pen 记录笔recording camera 录像机recording colorimeter 记录式色度计recording equipment 记录设备（录声设备和录影设备）recording infrared spectrophotometer 记录式红外分光光度计recording infrared tracking instrument 红外跟踪记录仪recording instrument 记录仪recording lamp 记录灯recording medium 记录媒质recording optical tracking instrument 记录式光学跟踪仪recording phase hologram 记录相位全息图recovery 复元recovery of spectrum 谱复原recovery photodiode 复元光电二极管recovery time 恢复时间recruitment services and executive search 人力服务recrystalization 再结晶rectangle 长方形，矩形rectangle function 矩形函数rectangular (1)长方形的，矩形的(2)直角的rectangular aperture 矩形孔径rectangular axis 直交轴rectangular Cartesian coordinate 直角笛卡儿坐标rectangular coordinate 直角坐标rectangular coordinate system 直角坐标系rectangular disk laser 矩形盒状激光器rectangular filter 矩形滤波器rectangular guideway 长方形形导轨，矩形导轨rectangular hyperbola 直角双曲线rectangular laser 矩形激光器rectangular mirror 矩形反射镜rectangular prism 直角棱镜rectangular wave 矩形波rectangular wave grating 矩形波光栅rectification (1)整流(2)检波(3)矫正(4)精馏rectifier (1)整流器(2)纠正仪(3)精馏器rectifier lens 整流透镜rectifier photo-cell 整流光电管rectifying (1)整流(2)精馏rectifying device 整流装置rectilinear 直线的rectilinear lens (1)消畸变镜头(2)直线透镜rectilinear motion 直线运动rectilinear propagation 直线传播rectilinear scale 直尺rectilinear scanner [直]线性扫描器rectilinearity 直线性rectoscope 直肠镜recurrence rate 重复率recurrent waveform 再现波形recurring decimal 循环小数recursion 循环，递推recycling 反复循环recycling spectrometer 再循环光谱仪recycling time 重复时间red end 红端（光谱）red light 红光red light laser 红光激光器red limit 红光极限（可见光）red [colo[u]r] (1)红色，赤色(2)红色的red-sensitive 红敏的red-sensitive cell 红敏光电管redder source 较赤热光源reduced (1)减缩的(2)约化，简化的reduced admittance 约化导纳reduced coordinate 约化坐标reduced data record 简缩数据记录，约化数据记录reduced eye lens 简化目镜reduced frequency 约化频率reduced image 缩小像reduced optical length 折合光程reduced pressure 减压reduced scale 缩小比例尺reduced spatial frequency 约化空间频率reduced vergence 折合聚散度reducer (1)减速器(2)减压器(3)还原剂(4)缩小仪reducible matrix 可约矩阵reducing lens 简化镜头reducing plane table 简化平板仪reducing printer 缩印仪reducing reflection coating 减反射膜reducing solution 还原溶液reducting theodolite 简化经纬仪reduction formula 换算公式reduction lens 缩影镜头reduction of operation 换算reduction printer 缩印机reduction rate 减速率reduction ratio 减速比reduncancy check 冗余校验redundancy (redundance)(1)冗余，多余(2)剩余redundant bit 冗余位redundant information 冗余信息redundant number 冗余数redundant operation 冗余运算reed 舌簧，舌片reed-type comparator 振簧式比较仪reek [block] 雾块（一种划痕）reel (1)卷轴，卷筒(2)磁片盒(3)绕线管reentrant (1)凹腔的(2)凹角的(3)重入的reentrant acousto-optic light modulator 凹腔声–光光调制器reentrant angle 重入角reentrant deflecter 凹腔偏转器refacer 光面器refacing 光面refection reducing coating 增透透膜（防反射膜）refection-enhancing coating 增反射涂层reference (1)参考，参照(2)基准，标准reference angle 参考角reference area 参考面积reference axis 参考轴reference beam 参考光束reference circuit 参考电路reference colo[u]r 标准色reference direction 参考方向reference disk 校对盒，标准圆盒量规reference ga[u]ge 校对测规，校对量规(2)校对计reference generator 参考信号发生器reference level (1)参考级(2)参考电平reference light 参考光reference line 参考线reference mark 参考标记reference phase 参考相位reference point 参考点reference point source 参考点光源reference scale 参考尺reference standard 参考标准reference surface 参考面，基准面reference system 参考系reference voltage 基准电压reference wave 参考波referenced line of sight 基准瞄视线refining 精炼，捉纯refinish 再抛光reflectance 反射比reflectance coating 反射涂层reflectance grating 反射光栅reflectance spectrometry 反射光谱学reflectance-increasing film 增反射膜reflectant lighting metering 反射光测法reflected glare 反射眩光reflected illumination 反射照明reflected light microscope 反射光显微镜reflected radiation 反射辐射reflected ray 反射线reflected wave 反射波reflecting action 反射作用reflecting anamorph 反射变像系统reflecting anamorphotic optical system 反射变像光学系统reflecting camera 反射式照相机reflecting collimator 反射式准直仪reflecting dichroic mirror 反射分色镜reflecting element 反射器，反射元件reflecting elements in series 串联反射元件reflecting film 反射膜reflecting finder 反射取景器reflecting galvanometer 反射电流计reflecting goniometer 反射测角计reflecting layer 反射层reflecting medium 反射媒质reflecting microscope 反射显微镜reflecting mirror 反射镜reflecting objective 反射物镜reflecting optics (1)反射光学(2)反射镜片reflecting plane 反射[平]面reflecting power (1)反射本领(2)反射比reflecting prism 反射棱镜reflecting screen 反射屏reflecting sphere 反射球面reflecting square 反光直角器，反光直角块reflecting surface 反射面reflecting telescope 反射望远镜reflecting telescopes 反射望远镜reflection (1)反射(2)反射波(3)反映reflection "image" 反射"像"reflection coefficent 反射系数reflection curve 反射曲线reflection density 反射密度reflection echelon grating 反射阶梯光栅reflection factor 反射因数reflection filter 反射滤光片reflection gauge 反射测量计reflection grating 反射光栅reflection hologram 反射全息图reflection interferometer 反射干涉仪reflection kernel 反射[波]中心reflection measurement 反射测定[法] reflection mirror 反光镜reflection objective 反射物镜reflection plane 反射平面reflection power 反射率reflection shield 反射屏reflection thickness ga[u]ge 反射厚度计。
Vol. 53 , No. 11Nov. 2019第53卷第11期2019年11月原子能科学技术Atomic Energy Science and Technology材料与构件深部应力场及缺陷 无损探测中子谱仪径向准直器的设计李映婵，陈东风"，刘晓龙"，李眉娟，李玉庆,韩松柏，陈星雨,贺林峰，孙凯（中国原子能科学研究院核物理研究所，北京102413）摘要：为设计材料与构件深部应力场及缺陷无损探测中子谱仪的径向准直器，实现大型工程构件的远距离准确取样，本文分析了径向准直器的实空间和相空间取样原理，介绍了目前径向准直器取样体积的解析与模拟计算方法,并利用0.2 mm 尼龙线测试了德国E3残余应力谱仪径向准直器的取样尺寸，基于 实验结果确定了采用JRR3解析方法作为径向准直器取样尺寸的计算依据％根据解析计算结果，研究了设计参数对径向准直器取样尺寸和传输效率的影响规律，并按照谱仪的空间几何结构，最终设计了谱 仪1、2、3、4、5 mm 径向准直器取样系统%关键词：材料与构件深部应力场及缺陷无损探测中子谱仪；径向准直器；取样尺寸；传输效率中图分类号:O57i. 56文献标志码:A 文章编号：1000-6931(I019)11-29507doi ：10. 7538/yzk. 2019. youxian. 0068Design of Radial Collimator of Neutron Diffractometer for Residual Stress and Defect in Material and ComponentLI Yingchan , CHEN Dongfeng ** , LIU Xiaolong * , LI Meijuan , LI Yuqing ,收稿日期：2019-01-30;修回日期：2019-05-07基金项目：国家重点研发计划资助项目（2017YFA0403704）国家自然科学基金委重大科研仪器设备研制专项资助项目（51327902）；国家自然科学基金青年基金资助项目（11605293）作者简介:李映婵（1976—）女，广东深圳人，高级经济师，博士，中子散射专业* 通信作者：陈东风，E-mail : dfchen@ciae. ac. cn ；刘晓龙，E-mail : liuxiaolong@ ciae. ac. cn网络出版时间：20190904 ;网络出版地址：http ： # kns. cnki. net/kcms/detail/11. 2044. TL. 20190903. 1428. 008. htmlHAN Songbai , CHEN Xingyu , HE Linfeng , SUN Kai(Department of Nuclear Physics , China Institute of Atomic Energy , Beijing 102413 , China )Abstract : The gauge principle of the radial collimator in real space and phase space wasanalyzed to design the radial collimator of the neutron diffractometer for residual stressand defect in material and component in order to set the gauge volume in large engineer- ingcomponentatfardistance.Theana&ytica&formu&asandsimu&ationswereintroducedtoca&cu&atethegaugevo&umeoftheradia&coimator.Theny&on wirewithdiameterof 0.2 mm wasusedtotestthegaugevo&umeoftheradia&co imatoratE3instrument !Germany.Accordingtotheexperimenta&resu&t !theJRR3ana&ytica&formu&awascho- sentodesignthegaugevo&umeoftheradia&coimator.Thee f ectoftheparameterson gaugevo&umeandtransmissione f iciencywasstudiedsystematica &y.Fina &y !theradia&2296原子能科学技术 第53卷collimators with gauge volume were designed in combination of the spatial geometrical layout with the parameters of 1, 2, 3, 4 and 5 mm.Key words : neutron diffractometer for residual stress and defect in material and compo nent # radial collimator # gauge volume # transmission efficiency现代工程结构和复杂装备之所以能安全、 稳定地发挥功效，是因为建造这些结构和装备 的材料具备承受外力载荷的能力。
