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      radio
    Efficiently implemented in field programmable gate arrays (FPGA), the generator prototype of the proposed sequence has been realized and incorporated into fast FH radio.
          
    In this method, 2-D feature information was constituted by using radio frequency and time-of-arrival, which analyzed the feature of radar pulse sequences for the very first time by employing structure function and empirical mode decomposition.
          
    The experiment shows that the method can efficiently extract the frequency of a period-change radio frequency signal in a complex pulses environment and reveals a new feature for the signal sorting of interleaved radar pulse serial.
          
    The Doppler spectral broadening resulted from non-stationary movement of target and radio-frequency interference will decrease the veracity of target detection by high frequency ground wave (HFGW) radar.
          
    The results indicate that the preprocessing not only makes the system acquire a higher ability of target detection but also suppresses the radio frequency interference by 6-7 dB.
          
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      the radio
    The results indicate that the preprocessing not only makes the system acquire a higher ability of target detection but also suppresses the radio frequency interference by 6-7 dB.
          
    Feasibility of diagnosis without generating the reference signal was exemplified by the radio-frequency sensors.
          
    A method, realizable in the form of a program on the personal computer, for computing signal attenuation in the radio link taking the relief of the underlying surface and characteristics of the antenna assembly into account is proposed.
          
    Radio Occultation Measurements of the Radio Wave Absorption and the Sulfuric Acid Vapor Content in the Atmosphere of Venus
          
    The results of the determination of centimeter (λ = 5 cm) radio waves absorption in the radio occultation experiments, carried out using the Venera-15and Venera-16spacecraft, are presented.
          
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      solar radio
    A technique of solar radio mapping with the RTF-32 telescopes is presented.
          
    The calculated CS position corresponded to the maximum brightness temperature of the flare detected by the Siberian Solar Radio Telescope SSRT (Institute of Solar-Terrestrial Physics, Russian Academy of Sciences, Siberian Branch, Irkutsk).
          
    Based on two-dimensional solar images obtained with the Siberian Solar Radio Telescope and the Nobeyama Radio Heliograph and using YOHKOH soft X-ray images, we investigate bright coronal points.
          
    The observations of the solar radio emission on September 11, 2001, with the RATAN-600 radio telescope (southern sector) at four centimeter wavelengths (1.92, 2.24, 2.74, and 3.21 cm) revealed synchronous brightenings in solar radio sources.
          
    We found a difference between the temporal variations of the radio emission from the halo and the solar radio sources under consideration.
          
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      radio continuum
    The possibility of estimating the redshifts of radio sources based on radio continuum observations is demonstrated.
          
    A new all-sky radio continuum survey at 408 MHz has recently been completed, which up to now represents the most accurate map of radio emission from the whole sky.
          
    A radio continuum map of a 1°5 X 1°5 region in the galactic plane nearl = 54° is presented at 49 cm with a resolution of 100 arcsec X 200 arcsec.
          
    Radiative transfer calculations in spherical geometry involving the dust as well as the gas component, have been carried out to explain observations covering a wide spectral range encompassing near-infrared to radio continuum wavelengths.
          
    We have used the Giant Meterwave Radio Telescope (GMRT) to measure the Galactic HI 21-cm line absorption towards 102 extragalactic radio continuum sources, located at high (|b| >amp;gt; 15°) Galactic latitudes.
          
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      其他


    From a large number of H_a photographs of limb flares,fifteen have been selected for reduction.The films were obtained with the standard Lyot-type Chromospheric patrol telescope at the Purple Mountain Observatory during the years 1959—1960. The photometric and positional measurements of limb flares have led to the following conclusions: (1)There are violent radial ejections of matter during the flash-phase of the flare. Usually a part of the flare is ejected to distances ranging from 2×10~4 km to 2.5×10~5 km...

    From a large number of H_a photographs of limb flares,fifteen have been selected for reduction.The films were obtained with the standard Lyot-type Chromospheric patrol telescope at the Purple Mountain Observatory during the years 1959—1960. The photometric and positional measurements of limb flares have led to the following conclusions: (1)There are violent radial ejections of matter during the flash-phase of the flare. Usually a part of the flare is ejected to distances ranging from 2×10~4 km to 2.5×10~5 km above the base of the chromosphere. (2)The mean velocity of ejection is of the order of 30 km/sec—400 km/sec.The maximum velocity appears in the initial stage of ejection and decreases later on.The acceleration of ejection is supergravitational. (3)The ejective motions of flares are regular and apparently connected with the magnetic fields of the active regions. (4)During the flash-phase of the flare the velocity of ejection varies directly with the rate of increase of brightness. In conclusion,it is noted that the appearance of radio events is closely related to the ejection.

    在大量的 H_α边缘耀斑电影胶卷中,为了精炼起见我们选取了15套.电影胶卷是在1959年—1960年期间用紫金山天文台的利奥型色球望远镜拍摄的.边缘耀斑的光度和定位测量得出下列结果:(1)在耀斑的闪光阶段存在着剧烈的径向物质抛射,常常耀斑的一部分被抛射到色球层之上高达2·10~4公里到2.5·10~5公里处.(2)抛射的平均速度是30公里/秒—400公里/秒的数量级,最大的速度出现在抛射的初始阶段,抛射的加速度是超引力的.(3)耀斑的抛射运动是有规则的,且明显地与活动区的磁场有关.(4)在耀斑闪光阶段,抛射速度直接地随亮度增加的速率而变化.最后,注意到了射电事件的出现与抛射密切有关.

    In this paper we briefly review the existing types of large radio telescopes and sug- gest certain principles to be considered in future design.With these in mind,a new type of telescopes is proposed.This consists of a large central paraboloid and a number of outer rings of discrete antenna elements. Fig.1 shows the arrangement of the paraboloid and one ring.When the two are connected by “correlation technique”,the resulting radiation pattern will be D∞F_1F_2, where F_1,F_2 are the field patterns of the paraboloid...

    In this paper we briefly review the existing types of large radio telescopes and sug- gest certain principles to be considered in future design.With these in mind,a new type of telescopes is proposed.This consists of a large central paraboloid and a number of outer rings of discrete antenna elements. Fig.1 shows the arrangement of the paraboloid and one ring.When the two are connected by “correlation technique”,the resulting radiation pattern will be D∞F_1F_2, where F_1,F_2 are the field patterns of the paraboloid and the ring respectively.By suitably chosing the radius of the paraboloid R_0,the radius of the ring α,and the number of elements in the ring n (R_0 and a being expressed in unit of the working wavelength), one may neglect the influence of the “secondary patterns” in F_2 (which occurs because the aperture of the ring is not full,but discrete).The Fourier transform of D∞F_1F_2 will then be expressed by equation (22) and shown in Fig.3,in which we take the radia- tion pattern of the paraboloid to be represented by Λ_2~2 (2πR_0r). When there are N rings with radii α_1=β_1R_0,α_2=β_2R_0,……,α_N=β_NR_0,and when they are connected with the central paraboloid by “correlation technique”,the radiation pattern will be D(r)=C_0[Λ_2(2πR_0r)]~2+CΛ_2(2πR_0r)[A_1J_0(2πα_1r)+A_2J_0(2πα_2r)+ +……+A_NJ_0(2παNr)],(26) where C_0,C,A_0…A_N are constants.The transform of D(r) is then expressed by equa- tions (37),(23),and (27),and may be adjusted to the form as shown in Fig.5.We see from the figure that the curve has nonzero values between the zero spatial frequency and the high frequency cut-off.Hence by the principle of “convolution correction” as pointed out by Wild in [11],the pattern may be “transformed” into a desirable one when a correcting function G is applied. To obtain such a curve as in Fig.5,that is,a curve with nonzero values below cut-off,one may choose the parameters β_m=α_m/R_0(m=1,2,…,N) so that the individual Fourier transforms corresponding to the paraboloid and successive rings will overlap in certain spatial frequency ranges.With this condition and the consideration of economy of arrangement,we may determine β_m and hence n_m [eq.(30)]. Table 1 gives the values of β and n as required in such design.In the sixth column of the table,we also give the half-power beam widths of the resulting patterns when they are corrected to Λ_1~2 (2πR_1r),where R_1=(β_N+1)R_0/2 (unit:R_0/2 minute of arc). For the sake of illustration,we take the total number of the rings N as 6.Denote the Fourier transform of radiation pattern D by (?),which curve is sketched in Fig.5. In the figure,the amplitude of (?) being modified to conform with the curve (?)_1~2 in order to suppress secondary lobes.The reverse transform of (?) is shown in Fig.6,which is the resulting radiation pattern.From it we see that the half-power beam width is about (200/R_0)′,the secondary lobe is tolerable,but rather broad. For correcting the pattern to Λ_1~2 (Fig.9),one has to find the correcting function G. As was done by Wild in [11],we have calculated the functions (?)=(?) and G in the case of zenith distance z=0.(Figs.7 and 8) Such calculations may be extended to other zenith distances,but the mathematics will be much more tedious. This type of radio telescope has the following essential characters: (1)It may be looked upon as the extension of a large paraboloid in the sense of improving the resolution and the collecting area.The field of application is wider than most of the usual types of large radio telescopes. (2)The system of antennas is good for wide range of wavelength variation. (3)At any stage,it always permits further developement by addition of outer rings. (4)It is advantageous to have the central paraboloid as large as practicable,since the resolving power is proportional to the factor (β_N+1)R_0.For given β_N,the total num- ber of elements required in the rings is the same for any R_0. (5)Away from the zenith,while the resolution in horizontal direction remains the same,that in vertical direction gradually deteriorates with the ihcrease of zenith distance. For N=6,the main lobe expands 1.8 times at z=60°,and 3.2 times at z=75°. (6)Beam swinging and scanning present some technical difficulties Owing to the path differences between different elements being functions of both azimuth and eleva- tion. (7)The “convolution corrections” of the radiation pattern are different for dif- ferent zenith distances.

    本文从讨论现有各种大型射电望远镜系统出发,根据技术条件和研究工作的发展趋势,提出在设计中应当考虑的因素.按照这些考虑,提出了由一个中央大型抛物面天线和多个环状分布分立天线组合而成的系统,导出这种组合的设计公式,并以环的数目 N=6为例,计算了具体的天线方向图形空间谱,并算出为了调整方向图形所需的改正曲线,以及通过两种改正方法所得到的图形.这种系统有着多用途的特点.同时它可以适用于很宽的波长范围,而且通过增加环数可以得到不断的发展.文中讨论了这些特点,提出了一些问题,并且对实现这种方案的技术条件作了简要的叙述.

    141 typical magnetic storms of the sudden commencement (SC) type, of which 45, 42 and 54 have strong, weak and no main phase respectively, have been selected from the magnetographs obtained at Zo-Se observatory during 1936~1962. Using data of solar flares and radio bursts of type 1V, the flares corresponding to the storms have been identified. The statistical properties of the three types of storms and their corresponding flares are investigated by statistical mathod. The charecteristics of corpuscular streams...

    141 typical magnetic storms of the sudden commencement (SC) type, of which 45, 42 and 54 have strong, weak and no main phase respectively, have been selected from the magnetographs obtained at Zo-Se observatory during 1936~1962. Using data of solar flares and radio bursts of type 1V, the flares corresponding to the storms have been identified. The statistical properties of the three types of storms and their corresponding flares are investigated by statistical mathod. The charecteristics of corpuscular streams emitted by flares are evaluated. By means of correlation analysis, the relations between storm's charecteristics and the charecteristics of flares as well of corpuscular streams are investigated. The main conclusions are as follows; 1. The flares producing the storms with strong main phase are stronger. They concentrate mainly near the central meridian of the solar disk; while the flares producing the storms with weak or no main phase are weaker. The distribution on the solar disk of the former have strong east-west asymmetry, while that of the latter are rather uniform. 2. The formation of the storm's main phase is closely related to the velocity of the corpuscular stream, while the relation with the density of stream, is poor. On the average, the density at the front of streams producing SC storms is 10~40 proton/cm~3. 3. The emitting angle of the corpuscular streams producing SC storms is about 120°±(20°~30°). The lower limit of the total kinetical energy of streams is 10~(27)~10~(28)erg. 4. a_(p max) and K_(p max)—maximum values of α_p and K_p during storms- are closely correlated with the velocity v of streams, while the correlation between the maximum amplitude ΔH_(max) of storm's main phase and v is very poor. 5. The geomagnetic latitude of the Sun, i. e that of subsolar point, affects not only the type, but also the intensity of storms, and it appears that the effect on intensity is more inportent.

    根据1936—1962年佘山地磁台磁照图,选出141个典型的急始型(SC)磁暴,其中强主相、弱主相和无主相磁暴分别为45个、42个、54个。利用耀斑和1V型射电暴等资料证认出对应的耀斑。用统计方法研究了三类磁暴及对应耀斑的统计特性。估计了耀斑抛射的微粒流的特性。用相关分析研究了磁暴特性同耀斑和微粒流特性的关系。本文得到的主要结论是: 1.产生强主相SC磁暴的耀斑较强,主要集中在日面中心经圈附近;产生弱主相和无主相SC磁暴的耀斑较弱,前者沿日面的分布有明显的东西不对称性,后者沿日面的分布比较均匀。 2.磁暴主相的形成同微粒流的速度关系密切,但同微粒流密度的关系不大。平均而言,SC磁暴对应微粒流前锋处的密度是10—40质子/厘米~3。 3.SC磁暴对应微粒流的抛射角约为120°±(20°—30°),总动能的下限为10~(27)—10~(28)尔格。 4.磁暴时ap和Kp的极大值ap_(max)和Kp_(max)同微粒流速度v关系密切,而磁暴主相极大振幅ΔH_(max)同v的关系却很不密切。 5.太阳的磁赤纬(卽日下点的地磁纬度)对磁暴的强弱和类型都有影响,可能主要影响强弱。

     
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