正曲率的曲面 的英文怎麼說
中文拼音 [zhēngqūlǜdeqūmiàn]
正曲率的曲面
英文
surface of positive curvature- 正 : 正名詞(正月) the first month of the lunar year; the first moon
- 曲 : 曲名詞1 (一種韻文形式) qu a type of verse for singing which emerged in the southern song and ji...
- 率 : 率名詞(比值) rate; ratio; proportion
- 的 : 4次方是 The fourth power of 2 is direction
- 面 : Ⅰ名詞1 (頭的前部; 臉) face 2 (物體的表面) surface; top 3 (外露的一層或正面) outside; the ri...
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The paper studies the surface geometry of globoidal indexing cam by applying the theory of conjugate surfaces and the method of coordinate transformation, presents the equations related to the main inducement curvature of the cam profiles, analysis and deduces the equations of two circumscription curves, which judge if the conjugate surface could mesh properly. some calculate examples and conclusion are given. the surface equation of the globoidal cam and conjugate equation are established
論文首先在分析空間嚙合原理基礎上,採用坐標變換法推導出弧面分度凸輪的工作廓面方程、嚙合方程和壓力角計算公式,對弧面分度凸輪的嚙合特性進行了深入的分析和研究,對判斷曲面能否正確嚙合的依據如兩類界限線方程以及誘導主曲率等進行推導,並給出算例。In the course of working, , the plow will make use of the shuttling method so that it can dig alternately either on the left or on the right. compared to the unilateral plow, it can improve the productivity because it can help leave off the soil 、 take from the consumed energy and reduce the empty journey. to meet the requests above, we will use a remote cylinder with both a small cubage and double functions, approximately designing the plow to be columniform and symmetric. after the experiment for a period in the field, we found that the most frayed areas had happened at the places of both plow shank and share and at the same time the base of the remote cylinder had ruptured suddenly
與單向犁相比,其優點在於:耕地無開、閉壟,地表平整,降低了耕后整地的能量消耗,減少了地頭的空行程,因而大大提高班次生產率。為了滿足犁體梭式作業的要求,我們採用了一隻小容積雙作用的液壓油缸;同時對犁壁曲面的形狀採用了近似圓柱形的對稱設計。但經過一段時間的田間試驗,我們發現:該犁犁胸部分的犁脛和犁鏵上的犁尖在工作中磨損較為嚴重;主犁梁和油缸缸體的連接部分(即油缸底座)突然發生了斷裂,造成整個犁體無法正常工作。This paper deals with the regular curves in a riemannian manifold with constant sectional curvature and the affine starlike curves in r2, r3 and r4
本文研究了具有常截面曲率的黎曼流形中的正則曲線及二、三、四維空間中的仿射星形曲線。The manufacture system of filament winding ( fw ) and fiber placement ( fp ) is the one of advanced equipment for frp products. it can be used to produce the products of the positive curvature gyration bodies, such as container cylinder, oil tank, tube, orb, cone, assembled body and so on. furthermore, it is more suited to machining some products of the complex bodies such as the surfaces of the negative curvature gyration bodies, the shell components which have slots and reinforced tendons
纖維纏繞/鋪放聯合製造系統是纖維增強塑料( frp )製品生產的先進製造裝備之一,可用於製造如圓筒容器、儲罐、管、球、錐形體或組合形體等正曲率回轉體的製品,更適用於製造含有負曲率的回轉體表面、具有深槽、加強筋的殼體構件等外形相對復雜的纖維增強塑料製品。And then, in this part, following the idea of topping [ 51, 52 ], we will show an isoperimetric inequality ( 6. 3. 1 ) on surfaces of non - positive gaussian curvature by means of the curve shortening flow on surfaces, this inequality can be considered as a generalization of the banchoff - pohl inequality in the euclidean plane
然後,仿照topping [ 51 ]和[ 52 ]利用平均曲率流證明等周不等式的想法,我們利用曲面上的曲線縮短流在gauss曲率非正的曲面上證明了一個等周不等式( 6First, we identify the homonymous points using normalized product correlation to revise the geometry distortion. in this method, the linear combination of correlation ' s three features is considered to improve the matching probability of homonymous points
本文首先選取同名點以校正幾何形變,採用歸一化積相關函數為選取準則,並以相關曲面的三個特徵量的線性組合來評價選取的同名點,提高匹配率。Considering the similitude law for shaking table test, we study the test results and obtain some conclusions which are a ) generally, the silty soil in test box liquefies and the liquefied time has relation with the amplitude of acceleration, b ) when the intensity is on and above eight degree, the silty soil deposit will be liquefied dramatically, c ) the relationship of the pore water pressure is relevant to the cycle loading which represents when the cycle loading ranges from little to great, the relationship is represent as a concave curve, or else as a protruding curve and tends to stability. ( 3 ) based on the triaxial compression test and the resonant column test, some studies are made such as a ) the duncan - chang parameters of constitutive model, b ) the dynamic shear modulus ratio and c ) the damping ratio of the site soil deposits. in order to deal with the test data, a computer program is compiled
( 2 )利用小型振動臺進行了k _ 0固結狀態下粉土的振動液化模擬研究,通過分析正弦荷載作用下的試驗資料,驗證了粉土的孔隙水壓力增長模式的合理性;從微分方程推導了基於土體振動臺模型試驗的相似律,並從模型實體、孔壓時程曲線和相似律等方面做出了分析,得出了如下結論:在小型振動臺試驗中,模型箱中的粉土都發生了液化,液化的時刻和輸入加速度幅值有關,而對頻率的變化不太敏感;粉土在相當於8 9度地震烈度的加速度幅值作用下可能產生嚴重的液化;孔壓的增長曲線形狀與施加的荷載有關:當施加荷載為由小到大的形式時,曲線形狀為上凹的曲線;當施加荷載為等幅的正弦荷載或荷載幅值由大到小時,曲線形狀為上凸的曲線,且逐漸趨于穩定。Because the data mutate on the position that is the edge, the normal curvature on some orientation changes from positive to negative. so it is thought whether some point is judged the edge - point by this character
由於邊緣是圖像上像素發生突變的位置,所以在圖像曲面上某一方向的法曲率值會出現由正到負的變化,故此應用這個性質來判斷曲面上某點是否為邊緣點。Moreover, we proposed a region - growing surface reconstruction algorithm. the filtering of the candidate triangles was improved a lot by constructing an influence region during the incrementally region - growing extraction of the surfaces. the construction of the influence region also contributes to make sure that the surfaces are geometrically and topologically correct
並在此結果基礎上,提出了一種區域增長式的曲面重塑演算法,它通過構造影響域提高了增量式區域增長抽取網格曲面過程中最優三角片的篩選效率,也確保了重塑曲面在幾何和拓撲上的正確性。In auto smooth method, we use the curvature and depth analysis to look for " bad point " automatically, and take the latitudinal curve to modify the surface ; referring to the tech of image processing, we import a interactive method to smooth surface based on image smoothing
在自動光順方法中,利用曲率分析及深度分析自動尋找「壞點」並採用緯向曲線重生成的方法予以修正;結合圖像處理的內容,引入了基於圖像平滑的互動式曲面光順方法,取得了滿意的效果。Abstract : variations of flow pattern, flow velocity in deep poo l and side bar, mainstream thread, and water surface, caused by excavation project, are investigated by two - dimensional mathematical model in an orthogonal curvili near coordinate system. the change of bed - load transport rate, and redeposition r ate are predicted. the influences of the excavation project on navigation are ana lyzed. grid - type and flat - type excavation alternatives are proposed and discuss ed
文摘:採用正交曲線坐標系下的河道平面二維數學模型,研究了嘉陵江何家磧邊灘采砂后河道流勢、流態、灘槽流速、主流位置、水面高程及比降的變化規律,預測了采砂方案完成後卵石推移質輸沙率變化及其對航道的影響,並對格形開挖和平整開挖方案進行了比較分析Secondly, to achieve the independent regulation of active and reactive power output from the generator side which is designed for the purpose of tracing the maximum wind - energy capturing. the paper has analyzed the mathematic model of the ac excited doubly - fed machine and the stator field orientation control strategy of the motor as vscf wind power generator. thirdly, it has put forward and designed the dual pwm converter with the capacity of energy flowing bidirectional aimed at the demand of rotor energy bidirectional flow. the author constructed reliable and integrated experimental system and did a series of experimental study including no - load, cutting - in network and power generation at, below and above the synchronous speed
論文首先分析了風機運行特性及其最佳風能利用原理,通過模擬及實驗驗證了採用直流電機的輸出特性模擬風力機的最大輸出功率曲線的可行性,並給出了模擬系統的硬體結構;然後為了實現交流勵磁發電機有功、無功功率獨立調節機理,分析了交流勵磁雙饋發電機的數學模型和在追蹤最大風能捕獲變速恆頻風力發電時必需的定子磁鏈定向矢量控制策略;針對雙饋發電機轉子能量雙向流動的要求,提出並設計了具有能量雙向流動能力的雙pwm交流勵磁用變頻器;最後為實現從理論到實踐的全面研究,研製出了一套小功率完整的雙pwm變頻器交流勵磁的雙饋風力發電機實驗系統,進行了空載、並網、同步速及上、下的發電運行等一系列的運行實驗;所完成的模擬和實驗研究均驗證了理論、模型和控制策略的正確性、可行性。Under this flow, the convex initial curve will preserve its perimeter, enlarge the enclosed area and make its curvature to be positive definitely. and as the time lasts, it will become more and more circular, and finally, as the time goes to infinity, the curve will converge to a circle in the hausdorff metric
本文證明在這種新的曲線流之下,閉凸曲線周長保持不變、所圍區域的面積不斷增大而曲率保持恆正(從而保持凸性) ,並且,隨著時間的推移曲線變得越來越圓,最終當時間t趨向于無窮大時,曲線在hausdorff度量意義下收斂到一個圓周。Secondly, two carbon fiber reinforced composite beams were fabricated, and their modal frequencies were measured by an experiment method. thirdly, delaminations were modeled by pairs of nodes with the same coordinates but different node numbers, while the modal frequencies of these beams with different delamination location and size were computed by an eas piezoelectric solid element. moreover, a novel method combining computational mechanics and neural network was demonstrated for composite health monitoring ; the first five flexure modal frequencies obtained by fem were modified by a primary revising approach and were used to train the neural network
本文較全面地評述了神經網路的應用模型、改進演算法等,編制了bp神經網路程序:制備了纖維增強復合材料試件,並進行實驗模態分析;利用坐標相同、節點號不同的方法模擬脫層損傷,基於eas列式的壓電固體單元計算了不同脫層損傷情況下的頻率信息;針對基於實驗數據訓練神經網路存在樣本不足的缺陷,本文提出了利用有限元方法對含有脫層損傷的復合材料試件進行數值模擬,以前五階彎曲模態頻率構建訓練樣本的新思路,並提出了一種初步的計算值修正方法,以此構建神經網路的訓練樣本:將實驗模態分析的結果送入訓練好的神經網路進行預測,實現了對復合材料梁的脫層損傷的定位和損傷程度的評估。Considering the die - cavity roughing being a 2. 5d cutting, a novel cutting force surface model is created based on orthogonal cutting tests
鑒于模具型腔粗加工常採用2 . 5維加工,提出一種通過正交切削試驗建立切削力曲面模型用於模具型腔粗加工進給率優選的新策略。The research indicate that the structured soft clay has below several characteristic, the viscous strain is produced during the stage of primary consolidation and of second consolidation, and in the prophase, the relation of stress - strain - strain rate is unique, so the form of constitutive model, such as, f ( v ', e ) = 0, f ( ' v, e, t ) = 0, ca n ' t describe strain behavior of soil skeleton rationally ; the time - dependent properties involve three aspects, in addition the time - dependent strain, apparent preconsolidation pressures that depend on strain rate, and the effect of creep compression on apparent preconsolidation pressures ; because of holding structural strength, the mechanics characteristic is determined by the magnitude of stress, and the compression curve is composed of several sections. by combining structural yield stress and it ' s characteristics with the improved time line model, a new one - dimensional elastic visco - plastic consolidation model is established
研究結果表明,結構性土的固結過程具有以下特性:主固結和次固結階段都包含有因土骨架的粘滯性移動而產生的變形,而且在正常固結階段,存在應力?應變?應變速率的唯一性, f ( _ v , e ) = 0 、 f ( _ v , e , t ) = 0形式的本構關系不足以描述土骨架的變形行為;固結壓縮過程中的時間效應包括三個方面的內容,除了應力應變關系與時間相關外,還包括粘滯性變形引起表觀前期固結壓力增加和屈服應力的應變速率效應;軟土的結構性使其力學特性與應力水平相關,壓縮曲線具有分段性。In the second part, we investigate the compact submanifolds m with the parallel isoperimetric section in the real space forms rm ( c ) and prove that if there exists a parallel isoperimetric section on m, and the sectional curvature of m is always greater than zero, then m is contained in a hyper - sphere ; and get that the gauss curvature of the compact surfaces m with constant mean curvature in constant curvature space r4 ( c ) is always greater than zero, then m is a totally geodesic surface or a sphere, where an isoperimetric on m means a unit normal vector field defined globally on m with m1 ( ) = constant
( 2 )研究了實空間形式r ~ m ( c )中具有平行等參截面的緊致子流形m ,證明了具有一平行等參截面的子流形m ,如果m的截面曲率恆正,則m包含在r ~ m ( c )的一個超球面內;對于常曲率空間及r ~ 4 ( c )中具有常平均曲率的緊致曲面m ,如果m的高斯曲率處處大於零,則m或為r ~ m ( c )中的全測地曲面或為一球面。這里m上的等參截面是m上整體定義的單位法向量場,使得m關於它的平均曲率m _ 1 ( )是常數。Secondly, the problem of the curve - surface mutual transforming and smooth - finishing have been analyzed farther. for the surface intersecting problem : owing to the introduction of the boundary points, as long as the intersecting points on a certain line, the full intersecting line can be gained. the intersecting line either intersects at the boundary of the triangle surface or forms the loop ; during the course of tracking, the selecting of the pace is restricted by the curvature, the number of the gained intersecting points are not in proportion as the chord - length ; the intersecting points not only record the coordinate and store the parameter
對兩曲面求交問題,當曲面細化足夠小時,曲面求交可近似看成曲面與平面相交問題,引進了邊界點的概念,因此只要知道交線上的任意點,就可以將跨越許多曲面片的整條交線計算出來,所求出的交線或者跨越曲面的邊界,或者形成交線環;從初始點出發跟蹤求解整條交線的過程中,步長的選擇採用了通過曲面片曲率來約束的方法,用該方法求出的交點在不同曲面片上的分佈數目不與弦長成正比;該求交方法包含了各曲面片的邊界線與交線的交點的求解,可獲得邊界交點的坐標值及其參數值。The method removes the bottleneck of transformation from complementary energy element with stress functions vector to potential energy element with simple displacements vector. what is the most important about this method is that it never destroys the original convergence of the transformed plane elasticity element and that it can maintain the original precision
本文方法列式簡單,所得板彎曲單元皆可通過常曲率分片試驗、有正確的剛體運動模式並具有與原始平面彈性單元相稱的良好精度,從而達到了將平面彈性單元轉化為板彎曲單元的目的。The sphere images of 10 balls were captured at 3 different positions as the flat cards. it is proved that curvature of object have no influence on hue distortion in this machine vision system, basically. so distorted hue of balls can be corrected by the model of corresponding position flat cards directly
5 、分別在上述三個位置採集10種顏色的球面圖像,驗證了在本研究所用機器視覺系統內,物體表面曲率對色度失真基本沒有影響,因此,對于球面物體的色度失真,可直接應用相應位置的平面色卡色度失真校正模型進行校正。分享友人