空間衰減 的英文怎麼說
中文拼音 [kōngjiānshuāijiǎn]
空間衰減
英文
apace attenuation- 空 : 空Ⅰ形容詞(不包含什麼; 裏面沒有東西或沒有內容; 不切實際的) empty; hollow; void Ⅱ名詞1 (天空) s...
- 間 : 間Ⅰ名詞1 (中間) between; among 2 (一定的空間或時間里) with a definite time or space 3 (一間...
- 衰 : 衰動詞(衰弱) decline; wane
- 空間 : space; enclosure; room; blank; interspace
- 衰減 : attenuation; decay; damping; reduction; rejection; weakening; deamplification; dampening; dying o...
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At present, the solar cells used on space aircrafts are still mainly si and gaas solar cells. however, the radiation resistance ability of these two materials is poor. since the photoelectric conversion efficiency attenuates rapidly with the radiation, the lifetime of si and gaas solar cells is short and their stability is not satisfied for space applications at van allen belt
目前國內外用於航天器上的太陽電池主要為si和gaas太陽電池,但這兩種材料的抗輻射能力較差,其光電轉換效率由於高空輻射衰減很快,因而壽命短,穩定性差,不能滿足用於vanallen強輻射帶的空間應用需要。Main conclusions drawn from the analyses of calculating results are as follows : ( 1 ) the microwave absorption of atmosphere gas have obvious attenuation at the wavelengths for cloud detection, thereinto, the water attenuation effect changes greatly, so the 94ghz cloud detecting radar should have water vapor attenuation correction scheme. ( 2 ) when 37ghz and 94ghz radars detect clouds, the difference between the atmosphere and cloud attenuation and the large variety of radar reflectivity conduce the intension of the radar backscatter signals change. ( 3 ) for the thin cloud layer and low water content of cloud, 37 - ghz radar backscatter signals are not as good as 94 - ghz radar, that is to say that the 94ghz radar has better capability in thin clouds detection
本工作得出如下結論: ( 1 )大氣氣體的微波吸收在測雲波段產生明顯的衰減,其中水汽衰減效應變化很大;即將上天的空間94ghz測雲雷達必須有水汽衰減訂正方案; ( 2 ) 37ghz和94ghz雷達測雲,由於大氣和雲衰減不同和雷達反射率的很大差異,導致雷達回波信號強弱不同; ( 3 )對雲層較薄、含水量較少的雲,在不計雷達參數的情況下, 37ghz雷達回波信號不如94ghz測雲雷達,也就是說94ghz對薄雲有更強的探測能力;對雲層較厚、含水量大的雲,由於強衰減的作用, 94ghz雷達回波信號小於37ghz雷達; ( 4 )從大氣衰減的不利因素方面考慮,空間94ghz雷達測高層薄雲的效果最好;測低層薄雲時需要考慮氣體衰減訂正;因濃厚雲的強衰減作用,探測其中下部的能力大大減弱,不僅要進行衰減訂正,而且要藉助其他信息來反演整個雲層的含水量垂直分佈; ( 5 )為了獲得從極薄到極濃厚雲的垂直分佈探測能力,未來測雲雷達系統最好採用雙波長甚至三波長(如94 、 37和13ghz ) 。As for a space - based cloud radar, the change of the radar reflectivity n and the change of attenuation rate along with the cloud liquid water content have been compared between 37 ghz and 94ghz. the transmittance t of single level cloud for different heights and liquid water content has also been calculated at 2 frequencies. by defining a = n tr, which combines both effects of radar reflectivity and transmittance, we have examined the values of a at 37ghz and 94ghz for high, middle and low cloud liquid water contents
對空間測雲雷達,討論了37ghz和94ghz這兩個頻率的雷達反射率和衰減系數隨雲液水含量的變化;計算了不同高度的單層雲在不同頻率,不同含水量情況下的雲層透過率_ ;定義a = _來綜合考慮雷達反射率和透過率對空間測雲雷達回波的影響,分析比較了雲含水量高、中、低時37ghz和94ghz的a值大小。We present a charge - transport model of the photorefractive effect with two deep traps ( two deep - trap model ) based on one deep - trap model and shallow - deep - trap model. we also found dark decay behaviors which accord with the two deep - trap model in the two - beam interference experiments. the fast decay - time constant of the space - charge field is obtained as 714s
此外,在ce : batio _ 3雙光束干涉光折變光柵的暗衰減實驗中,也觀察到了符合雙deep模型的衰減現象,得到光折變空間電場快衰減時間常數714s ,約12分鐘。This movie demonstrates the phase difference and the amplitude decay of the e and h field in freespace
本影片可看出真空中電場和磁場之間的相位差和振幅衰減的現象。One of the key technologies of deep space communication is channel code. there are differences between deep space communication and the common space communication. because the former one has some characteristics, such as extending information transmission, and seriously reducing signal energy, it is necessary to ensure the information transmission band and the exactness by using the special means
通道編譯碼是深空通信中的關鍵技術之一,深空通信與一般的空間通信不同,深空通信具有信息傳輸時延大、信號能量衰減嚴重等特點,必須有特殊的手段保證其信息傳輸的帶寬和準確。In the terms of interpolation, the image reconstructed from nearest interpolation or linear interpolation has good edge but serious noise ; reconstruction from 4 * 4cubic interpolation or three b - spline or three - order lagrange interpolations has better local character. 2 x 2cubic interpolations which has both better edge and local character is the ideal interpolation, the following is the basic principle during reconstruction : ( 1 ) the more width of interpolation, the more number of summation and the more order of interpolation polynomial, the higher of density resolution ; ( 2 ) the more of interpolation polynomial and width of interpolation, the more of reconstruction time simultaneously, aimed at eliminating the effects of noise contained in projection data, in this paper, author analysis cause and effects of common artifacts. importantly, discusses convolution back - projection reconstruction algorithm with a shift axis of rotation has been derived for correcting images that acquired with a divergence axis of rotation using the fan beam geometry with an angle - equaled detector
在ct圖像重建時,選擇有限帶寬窗有較好的空間解析度,三角形窗有較好的密度解析度,選擇餘弦窗則使得空間解析度與密度解析度的折衷;從窗函數的頻譜角度來講,可以用於圖像重建的一個良好的卷積窗函數應該具備以下條件: ( ? )小的3db帶寬b ,即最小的主瓣寬度; ( ? )最小的旁瓣最大峰值a ; ( ? )最大的旁瓣峰值衰減速度d ;就內插函數而言,臨近點內插與線性內插重建圖像噪聲大,但有較好的邊緣與細節; 4 4三次內插、三次b -樣條與四次拉格朗日多項式內插圖像平滑,局部特性較好。The main cause of signal ' s decrease in infrared channel of spacecraft flying remote sensing instrumentation is water vapor deposition on the surface of low temperature optical instruments which released from materials
摘要空間遙感儀器紅外通道的信號衰減,人軌初期的主要原因是由於材料釋放的水汽在低溫光學窗口表面沉積,導致紅外透射率降低所致。Optical attenuation, widely applied in many fields, can be adopted to acquire single - photon sequence that is foundational in quantum key distribution. we obtain single - photon sequence by precisely controlled optical power distribution along outlets of manifold consist of beam splitter instead of the attenuation by time sequence due to loss
用線性分束耦合器形成多個輸出口,將光強的時序衰減變為光強沿輸出口的空間分佈,研製出了量子保密通信用的精密控制的強衰減器,實現了對光子數的精密控制。We give a center manifold theorem in the neighbourhood of the equilibrium point, and prove that the center manifold is exponentially decaying
在此平衡點附近建立中心流形定理,並證明中心流形有空間指數衰減性。In the attenuated - total - reflection ( atr ) multi - layer structure, light reflectivity can be highly dependent on layer parameters such as the layer thickness and refractive index. a tiny change in these parameters can lead to a large change in the light reflectivity
衰減全反射( atr )結構是光學上一種較為特殊的反射型結構,在一定的條件下,反射光的空間強度和頻譜成分都會受到結構參數的影響和控制,同時反射光也攜帶上了結構本身的信息。This paper has studied the mean attenuation, scattering, and back scattering cross sections of groups of small rotating spheroids about characteristics of microwave scattering when their rotatory axes are oriented at random in any direction in 2d plane and 3d space respectively under the condition of normal distribution, and that those physical quantities are changed with different variance, expectation and wave lengths of incident electromagnetic wave
本文研究旋轉軸方向分別在平面內和空間中隨機取向呈正態分佈時的小旋轉橢球粒子群的平均衰減截面、平均散射截面、平均後向散射截面等微波散射特徵,以及這些物理量隨軸向分佈期望、方差及入射電磁波波長的變化。From an analytic treatment, the state is determined by the nanotube diameter rather than chirality. the corresponding image of local density of states in real space shows a highly localized state around the defect
然後逐點計算局域態密度發現,在實空間準束縛態是一個非常局域化的效應,離開缺陷即迅速衰減。The work including : ( 1 ) svm based auto detection and segmentation of left ventricle mri image the aim of the segmentation of the left ventricle mri image is to find out the inner and the outer contour of the left ventricle, while for that the structure of the heart is very complex, meantime the tag lines may also decay, the contrast of the object and the background will also descend, which still make the segmentation more difficult
同時,對核空間方法在圖像處理領域的幾種應用進行了論述。本文工作包括: ( 1 )設計基於svm的mri左心室圖像的自動檢測及分割過程心臟mri圖像分割的目的是為了找出mri圖像中左心室的內外輪廓,但是由於心臟的解剖結構非常復雜,再加上標記線會隨時間衰減,目標和背景的對比度會下降,這使得圖像的自動分割更加困難。In a infinite and empty space the geomagnetic field falls off in strength with the third power of distance
在無限和真空的空間中,地磁場在強度上隨距離3次方而衰減。In particular the energy decay of the solution is obtained by the use of komornik ' s integral inequality
特別地,我們利用komornik積分不等式得到弱解的能量衰減估計,其中a _ 1 , a _ 2和n為一些hilbert空間上的有界線性運算元Traces of dyes indicate that the stable length increases with an augment of h, and the relations between spatial attenuation rates of disturbance and wavenumbers are correspondent with theoretical results by the analysis of spatial mode
染色線觀測顯示h值增大使擾動失穩距離增加,擾動衰減率與波數的關系同空間模式穩定性分析的理論結果定性一致。We first give a proof of the global existence and uniqueness of solution for the problem by useing of a " stable set " method. moreover, we treat the so - called h2 - solutions instead of usual energy finite solutions and derive a precise decay estimate for the energy
文中採用「穩定集」的方法得此問題解的整體存在性及唯一性,並且運用h ~ 2空間取代通常的能量解得到了能量衰減估計Space - time coding technique is a coding technique which is applied in mimo system. it correlates to multiple antennae and signals transmitted in different periods in temporal and spatial domains, which enable the receiver can overcome fading over mimo channel and reduce error code transmitted
空時編碼是一種用於mimo系統的編碼技術,該編碼在多根發射天線和各個時間周期的發射信號之間能夠產生空域或時域的相關性,這種空時相關性可以使接收機克服mimo通道衰落和減少發射誤碼。In addition, this paper provides the co - plane display of the volumetric - scan data of two weather radars. in a result, time - space accordance effect and attenuation correction effect for data of two weather radars can be viewed directly
本文進行了雙雷達聯合探測資料的共面顯示,可以比較直觀地看到雙雷達資料的空間對應效果和衰減訂正的效果。分享友人