無析出帶區 的英文怎麼說
中文拼音 [wúxīchūdàiqū]
無析出帶區
英文
precipitation free zone-
The paper concludes that the changing rate of ndvi of rain forest in tropic is the smallest, the changing curve is smooth, while the changing rate of ndvi of the deciduous broad leaf forest in warm - temperate zone is the largest the change of ndvi is the most conspicuous in winter and spring ( especially in april ) while is not conspicuous in summer and autumn by analyzing the change of ndvi along latitude using the ndvi value of different vegetation types along the same longitude. the vegetation index from warm temperate zone to semitropical zone has obvious transition, while other areas have no distinct change by analyzing the change of ndvi from temperate zone to semitropical zone to tropical zone using ndvi averagejn the same time it is concluded that the sink value in the beginning of the year 1995 is from the influence of the monsoon in east of china by analyzing the ndvi curve of several typical needle leaf forests. the relation between ndvi value and temperature is conspicuous while the relation of precipitation is less or not by analyzing the relation between ndvi and temperature and precipitation finally it can get the conclusion that the change of river area is the smallest, the change of sienna area is the greatest by analyzing two phases of tm data in 1987 and 1997 with rs technic
利用從同一經度的不同森林類型ndvi值分析，沿緯度方向ndvi變化可得出， ndvi在冬春季變化最明顯（尤其是在4月份最大） ，而在夏季和秋季變化不明顯。利用ndvi均值進行分析，從暖溫帶到亞熱帶到熱帶的變化情況發現，從暖溫帶到亞熱帶ndvi指數形成明顯的階躍，而其它區域沒有太大的變化，同時對幾種典型的針葉林曲線分析可知其年初的凹值源自於我國東部季風的影響。利用ndvi數據分析其與月均溫度與降水的相關性得出與溫度相關性較為顯著，而與降水相關性不顯著或無相關性。To achieve non pollution, ecological strategy target on chemical indu stry area, this article put forward planning and designing idea which is more marketlized, industurized and ecologized and planning and allocation structure which covers two areas and five districts after analyzing the existing problem of xining chemical industry area
摘要本文通過對西寧市化工園區存在問題的分析，圍繞建設無污染生態型化工園區的戰略目標，提出了市場化、產業化、生態化的規劃設計理念和「兩帶五區」的規劃布局結構。The control tactics of space voltage vector are investigated, and the simplified algorithm which judges the sector location of reference vector and calculates switch operation time is put forward. by analyzing the current hysteresis control, the relation between switch frequency, and hysteresis bandwidth and input inductance of pwm rectifier is deduced. by applying instantaneous power theory, the principle of pwm rectifier power control is analyzed, and the direct power control by matlab toolbox through estimating active power and reactive power with virtual flux is realized, and the simulation results prove that it is correct
對常用空間電壓矢量控制策略進行分析，提出了給定參考矢量所在區間判斷的簡化方法，以及電壓矢量作用時間的求取方法；分析了電流滯環控制策略，推導出開關頻率與滯環帶寬以及整流器輸入電感之間的關系；應用瞬時功率理論分析pwm整流器功率控制原理，通過虛擬磁鏈估計有功功率和無功功率，用matlab實現了直接功率控制，並驗證了該控制方法的正確性。Depending on how the ground surface is denuded, the feature of the current crustal stress field and rock stress environment can be calculated analyzing the result in this paper : by analyzing the recovering feature of the elastic deformation of the rockmass in unload - stage under various pressures, it has been found there is close relationship between the recovering degree of the elastic deformation of the rockmass and the unloading degree of the pressure the direction of the major principal stress in the crustal stress field is not consistent with the direction of the crushing stress regional tectonics borne during the last tectonic movement. the evolving degree of the regional geomorphology evidently affects the current crustal stress field, which changes from the self - weight stress field to the horizontal stress field, with the changing of the eroding degree of the regional geomorphology ranging from valley area to hilly country to flat country. in valley area, where there is two stress belts, the bankslope s tress belt and the self - weight stress belt within the mountain. the direction of the major principal stress is nearly parallel to the ground surface and inclines towards the valley in the bankslope stress belt. it is nearly vertical in the self - weight stress belt
通過本文的研究成果，根據區域性地貌的演化特徵，我們可以大致地對現今地應力場進行判斷：在分級卸荷條件下，巖體中彈性變形的恢復具有明顯的規律性，這種規律對于研究地應力場的演變是有幫助的；地應力場中最大主應力方向與區域構造形跡在最近的構造運動中所受區域性擠壓應力的方向無明顯的對應性；區域性地貌形態的演化程度對現今地應力場的特徵具明顯的影響，隨著區域性地貌侵蝕程度由峽谷區、丘陵區、平原區的變化，現今地應力場特徵由自重應力場、水平應力場為主含少量自重應力場特徵向水平應力場的規律變化；在峽谷區，山體中具有兩個應力帶：自重應力帶和卸荷應力帶，最大主應力方向在卸荷應力帶中近平行於坡面並傾向于河谷、在自重應力帶中近於直立；根據原始地面遭剝蝕的程度，可以大致地估算最大主應力和中間主應力的量值和方向；在丘陵區和平原區，最大主應力的方向近於水平，並與附近區域性侵蝕盆地和河流的展布方向基本平行，根據原始地面遭剝蝕的程度，可以大致估算其最大主應力的量值；根據區域性地貌形態的特徵來分析工程區的現今地應力場特徵，並進而大致了解巖石的應力環境，這種分析方法得出的結論與許多實際的地應力測試成果基本一致，對于大型水電工程地下廠房和壓力隧洞的設計是有所幫助的。The conformal microstrip antenna with some unique character has been applied in many fields, especialy on speedy objects. in this paper, an efficient fdtd algorithm is introduced to analyse the microstrip antenna. firstly, the fdtd formula in descartes coordinate system and in cylindrical coordinate system are obtained from the time _ dependent maxwell equations using the yee algorithm in a calculating region where the dielectric parameters are independent of time and space. the choice of the space discretization units and the time discretization interval are discussed which are decided by the accuracy and stability respectively. the shape and setup of the excitation source are discussed too. the excitation source is chosen to be gaussian pulse in shape. secondly, the mur ' s first - order and second - order boundary condition are deduced in cylindrical coordinate system. the methods of transforming radiation fields from near zone to far zone in the frequency domain and in the time domain are presented when fdtd is applied to analyse the characteristics of far zone. finally, three kinds of microstrip antennas are analysed. they are a slot antenna that lies on a plane ground of a microstrip, a slot antenna that lies on a cylindrical ground of a microstrip and a microstrip line _ fed aperture coupled stacked rectangular patch antenna in cylindrical coordinate system
本文從麥克斯韋旋度方程出發，建立了笛卡兒坐標下無源空間中均勻無耗媒質的fdtd基本方程和圓柱坐標下無源空間中均勻無耗媒質的fdtd基本方程，詳細討論了fdtd法計算中時間步長和空間步長的選取原則以及激勵源的類型和設置；推導了mur一階和二階邊界條件在圓柱坐標下的差分格式；給出了在用fdtd法計算天線的遠場輻射特性時必需採用的頻域和時域近場遠場變換技術；最後用fdtd法計算了平面微帶縫隙天線、柱面共形微帶縫隙天線和柱面共形微帶層疊天線的輸入阻抗和遠區輻射場，並分析了天線的一些參數的變化對天線輸入阻抗的影響，得出了一些有用的結論。分享友人