流形拓撲 的英文怎麼說
中文拼音 [liúxíngtàpū]
流形拓撲
英文
topology of mainfolds-
Research and development of graphlike manifolds homeomorphism class
圖式流形拓撲分類的研究進展Using the topological rules of the surface flow pattern, the separation configurations on the suction surface at different bowed angles is discussed
應用壁面流譜的拓撲法則,詳細討論了不同彎角下的分離形態。In the framework, a control mesh may be arbitrary one - dimensional or two - dimensional orientated topological manifold, and the curve or surface is defined on differential manifold homeomorphic to the control mesh with a potential function as its basis functions. this method is an extension of nurbs, which efficiently overcomes the limitations of nurbs
廣義有理參數曲線曲面定義在與控制網格拓撲同胚的微分流形上,以高度一般的勢函數為基函數,其控制網格可以是任意的一維拓撲流形和二維可定向拓撲流形。A topological study of representative single - stage pfc converters are presented. in sigle - stage pfc approach, there are two important issues of concern. one issue is how to implement the input current shaper ( ics ). another one is how to control the energy - storage capacitor voltage below 450v
本文對現有的單級pfc變換器拓撲進行了詳細的分析,指出在單級pfc變換器中,必須解決兩個問題:如何實現輸入電流整形和控制電容電壓在450v以下。In the skeleton extraction, an novel approach for extracting the skeletons directly from the gray images is developed by simulating the procedure of water eroding the topography surface. the resultant skeletons are single - pixel width and connected. it also lies in the middle line of the object and keeps the topological properties of the original image unchanged
在骨架提取方面,論文提出了一種通過模擬水流沖刷地形表面的過程來直接從灰度圖象中提取目標的骨架的高效演算法,它可以得到連通的、保持目標的拓撲屬性的、處在目標的中線上的、近似單象素寬度的骨架。Abstract : this paper uses the topology theory to analyze the surface flow spectrums of straight, positively curved and negatively curved cascades with relative tip clearances of 0. 023 and 0. 036, finds apparent differences of topology and vortex structures in the blade tip and the suction side wall corner of single type of cascade with this two clearances, and studies the mechanism of the difference formation as well as their effects on the energy loss
文摘:應用拓撲原理分析了葉頂相對間隙為0 . 023和0 . 036的渦輪直葉柵和正、反彎葉柵的壁面流譜,發現在兩種間隙下同類葉柵的拓撲與旋渦結構在葉頂和吸力面壁角明顯不同,探討了差別形成的機理及其對能量損失的影響In chapter 2, the nonlinear feature of iron core of transformer in switching power supply was studied. according to the characteristics of switching power supply, the topology structure of resonant converter was selected. the characteristics of out put voltage and current vs. frequency for the three kinds of resonant converter were analyzed and compared
在第二章中,研究了高壓開關電源中高壓變壓器的非線性特性,選擇了諧振變換器作為高壓大功率開關電源的電路拓撲結構,並對三種形式的諧振變換器的電壓及電流頻率特性進行了分析比較。In order to obtain three - phase four - line ac output, system applied the four - legged main circuit topology. with the 3d - svm, the power system realizes voltage regulation and three - phase four - line output. meanwhile, this kind of control is easy to be realized in the digital inverter
為實現三相四線的交流輸出,變換器電路採取四橋臂新型拓撲,其控制採取了三維空間矢量調制,實現了變換器的在線調壓及輸出中點的形成,具有良好的動靜態性能,且這種控制思想可以方便地在現有數字變換器平臺上實現。Its properties and design method is discussed in chapter 4. for control meshes with arbitrary topology, we present a universal method in chapter 5 to construct parametric curves and surfaces. generalized rational parametric surface can be controlled precisely and flexible, and it is easy to model local features and 3d primitives
然後,在第五章中,我們將控制網格進一步推廣到任意可定向二維拓撲流形,提出了一個通用的方法將控制網格映射到與之拓撲同胚的微分流形上,統一了廣義有理參數曲線曲面的構造過程。Firstly, this paper introduces the asynchronous motor model, and compares it with the dc motor ’ s. then the paper studies the principle of vector control, and proposes an improved current model of rotor flux observer. this paper also studies the three - level inverter ’ s topology, working principle, the neutral - potential unbalance mechanism and its controlling strategy. the paper especially studies the svpwm in details. the interface between the vector control and the three - level inverter is studied in details, including the generation of reference voltage vector, its judging of the sector and triangular regions, and the working mechanism after it sent into three - level inverter. when synthesizing the reference voltage vector, select the vector which only includes p and o states as the starting vector, thus eliminate the vector shift problem when sector changes. this paper fully takes advantages of the powerful functions of matlab / simulink to set up the simulation model. this construction is very explicit. the simulation results verify the inverter voltage output is correct, the rotor flux is steady, the asynchronous motor ’ s dynamic and steady state performances and speed modulation are excellent
本文首先介紹了異步電機的數學模型,在此基礎上將異步電機的數學模型與直流電機的數學模型進行了比較;然後介紹了矢量控制的基本原理,採用了一種改進的轉子磁鏈電流型觀測模型;對三電平逆變器的電路拓撲、工作原理、中點電位不平衡的機理及控制方法進行了介紹,詳細分析了空間矢量脈寬調制策略。本文對異步電機的矢量控制與三電平逆變器之間的介面進行了詳細的研究,包括:參考電壓矢量的形成、所落扇區與具體小三角形區域的判斷、送入逆變器之後的工作機理。在參考電壓矢量的合成時,選擇只包含p 、 o狀態的空間電壓矢量作為起始矢量,解決了扇區切換時的矢量突變問題。The prototype test results indicate : voltage mode and current mode ac - ac mode ac / ac converters with high frequency link have the advantages such as high frequency electrical isolation. simple topology, two - stage power conversions, high power density, bidirectional power flow, good line current waveform, no audio noise, high converting efficiency, and high input power factor etc. this kind of converter lay the key technical foundation on new type regulated sinusoidal ac power supply, electronic transformer, ac regulator, and wave converter etc
試驗表明,這類變換器具有高頻電氣隔離、電路拓撲簡潔、兩級功率變換( lfac hfac lfac ) 、功率密度高、雙向功率流、無音頻噪音、變換效率高、網側功率因數高等優點。為新一代正弦交流穩壓器、電子變壓器、交流調壓器、同頻波形變換器的實現奠定了關鍵技術基礎。In chapter 4, based. on the recognizability of 2d manifold, an algorithm is presented for topologic reconstruction from scattered points
第四章提出一種基於二維流形可辨性的散亂數據曲面拓撲重建演算法。The thesis presents a group of direct ac / ac topologies including single and three phases ac / ac converters which are based on simple dc - dc topologies and realized by using the single - power tube four - quadrant switches. with only two power switches, these single or three phases ac / ac converters can achieve high quality four - quadrant ac / ac conversion by simple configurations and simple control schemes. the thesis mainly researches on the single phase ac / ac converter in the topologies including ac _ buck and ac _ cuk
本文介紹了基於直流buck 、 boost和cuk電路,採用單有源四象限開關實現功率雙向化的直接ac / ac變換拓撲族,該拓撲族中的單、三相變換電路均只使用兩個功率開關,可實現波形優良的同頻ac / ac四象限變換,具有電路結構簡單、控制簡便、可實現小型化等優點。On the basis of raster digital elevation model ( dem ) data over the laohahe river catchment in the upper and west area of the liaohe basin within inner mongolia autonomous region, the digital elevation drainage network model ( dednm ) is applied for assigning flow - vector directions over flat and depressional areas of the dem, for identifying stream network and watershed divides, and for establishing spatial topological structure of subcatchments and stream network
基於遼河水系老哈河流域柵格數字高程模型( dem )數據,採用數字流域水系模型( dednm ) 、河流工具rivertools 、地理信息系統arcview軟體,根據地形提取水系信息,構建數字流域水系、子流域與河網的空間拓撲關系。Rationality of network form is very important because it relates to accessibility and the attracted quantity of traffic. multi - index calculation for medium / small network form is carried out in this dissertation, graph theory and network flow theory is also used for topological analysis for medium / small network
路網形態關繫到交通的可達性以及吸引的交通量的大小,其合理性非常重要,本文對中小型路網形態進行了多項指標的計算,並利用圖論及網路流理論對中小型路網進行了拓撲分析。Based on the analysis of topology structure of parallel mechanisms and using differential topology and differential manifolds as mathematical tools, we propose a new classification method. this method classifies singularities of parallel mechanisms into two basic types, i. e. topology singularity and parameterization singularity. this kind of classification has clear physical and mathematical meaning and fully reveals the characteristic of configuration space of parallel mechanisms
採用微分拓撲和微分流形等現代數學工具,在對並聯機構位形空間的拓撲結構進行分析的基礎上,提出了一種新的奇異位形的分類方法,即把奇異位形分為拓撲奇異位形、參數化奇異位形兩種類型,這種分類方法充分體現了並聯機構位形空間的特點,具有十分明確的物理和數學意義。In section 2, we study the fixed point, stable set and unstable set of this system. for given parameters a trapping region is found with the property that any interval of unstable set will be expand under the map, so we get the conclusion that the system has infinitely many homoclinic orbits. as a consequence of the previous conclusion, we discuss the attractor of the system
在本文中,我們討論了一個分段線性模型,它是物理學中用來模擬r - l - diode電路行為的數學方程,通過研究,我們得到該系統的一些拓撲性質以及符號動力學中的一些結論,主要內容如下:在第二節中,我們對給定的參數值,通過數值計算研究了該系統的不動點,不動點附近的穩定集與不穩定集,發現該系統中存在一個捕捉區域:該區域中的不穩定流形總體上是擴張的。According to topological structure of control mesh, we generate generalized rational parametric surfaces in two manners. for a control mesh with consistent parameterization, the surface can be easily constructed because it can be mapped to differential manifold directly
對于具有簡單拓撲結構,存在著一致的全局參數化的控制網格,我們將把控制網格直接映射到微分流形上,因此可以很容易地對曲面進行構造和控制。This software has functions of graphic editing, network topological analysis, power information database management, power flow calculating, power loss and reactive power optimization analysis
該軟體具有圖形編輯、網路拓撲分析、電網信息數據庫管理、潮流計算、電能損耗計算和無功優化分析等功能。The low bounds of topological classes in k8 and k9 graphlike manifolds
9圖式流形的拓撲分類的下界分享友人