查询词典 arcs

The epicontinental volcanic magma arcs and residual sea basins that occurred at the stages of the oceanic crust subduction and oceanic basin closure, and the epicontinental volcanic...

在洋壳俯冲和洋盆闭合阶段陆缘火山岩浆弧、残余海盆和俯冲带上形成的陆缘-火山碎屑沉积相、含碳质沉积相及混杂蛇绿岩块等是金丰度较高的地质体，构成了成矿系统潜在的矿源层。

This thesis investigates the profile extraction and shape optimization on the result of topology optimization of planar compliant mechanisms. The main context includes the following work:(1) summarizing and analyzing the recent research status, some harvest and unsolved problems;(2) analyzing the conceptual design of planar path-generating compliant mechanisms and its mathematical model and tools;(3) Modifying the method of density contour as the method of profile extraction, and developing a method to optimize the density function in the profile extraction according to the requirement of the design of compliant mechanism;(4) developing a method to abstract the compliant mechanism into a form of links and joints by using the principle of connectivity on topology;(5) developing a method of shape optimization of planar path-generating compliant mechanisms, by representing the profile of the abstracted compliant mechanism as simple curves such as straight lines and arcs, establishing the models of the size optimization of the parameters of these curves, so that the compliant mechanism has a machinable shape;(6) At last, proving the feasibleness and effectiveness of the design method by making simulation design and validating it in FEA software.

主要工作包括：(1)分析了柔顺机构拓扑优化和形状优化的研究现状，分析了目前柔顺机构的研究重点、主要成果和尚未解决的问题；(2)分析了基于SIMP的柔顺机构概念设计方法及其相关工具和模型；(3)针对柔顺机构轮廓提取的特殊要求，提出了密度等值线法的改进方案，对密度函数插值点密度值进行优化，提出优化模型和选择优化算法；(4)根据轨迹输出平面全柔顺机构自身的形状特点，提出了轨迹输出平面全柔顺机构的抽象方法，即应用拓扑学上的连通性原理将柔顺机构抽象成杆件和结点形式，并对相应的数学原理进行了证明；(5)提出了平面全柔顺机构的形状还原和尺寸优化方法，对抽象的柔顺机构进行还原，将其轮廓还原成简单曲线的连接，从而建立尺寸优化模型，对机构进行尺寸优化设计，在得到可加工的机构轮廓的同时又能对关键部位进行特别处理；(6)进行了柔顺机构的数值仿真设计，并将所得设计结果导入商用有限元软件中进行仿真实验，证明了设计方法的可行性和有效性。

I worried most about studying Mandarin full-time, the difficulty of mastering the lan-guage's four tones and the intricate arcs, fishhooks and grids that make up written Chinese.

我尤其担心要全时学中文，光是要精通中文发声的四声及构成中文书写错综复杂的弧形、钩钩和方格已经够难了。

Designed control points of plane form with homocentric arcs and ball markers.By the moment invariants and least-squared procedure of ellipse fit, the markers wererecognized and located automatically with high precision.

设计了平面型多重圆弧编码控制点及立体控制点，结合边缘矩的不变性和椭圆最小二乘拟合技术实现控制点的精确定位。

Then the 3D data from each stereo visionmeasuring unit can be translated into a unique frame of refrence.2. Designed control points of plane form with homocentric arcs and ball markers.By the moment invariants and least-squared procedure of ellipse fit, the markers wererecognized and located automatically with high precision.3. Studied the technology of camera self-calibration, according to the camerawith wide field of view, set up the distorted projection camera model.

通过被测物表面的控制点，将局部测量数据统一到全局坐标系中。2、设计了平面型多重圆弧编码控制点及立体控制点，结合边缘矩的不变性和椭圆最小二乘拟合技术实现控制点的精确定位。3、研究了相机的自标定技术，针对大视场相机的特点，建立了非线性相机成像模型，采用优化算法完成了相机的内、外部参数标定。

Using hydrodynamical/N-body simulations and pure dark matter simulations, we found the dark haloes in the first kind of simualtions are more concentrated than in the second kind of simualtions. This result could increase the predicted probability of giant-arcs in gavitational lensing and cancel the great difference between the theoretical and observational results.

用含气体的数值模拟与纯暗物质的数值模拟比较，发现前者暗晕中的暗物质分布比后者中的更加密集，密集参数更大，这可能可以提高理论预言的引力巨弧的概率从而弥补理论与观测结果间的差距。

The treatment was performed using 4 to 6 arcs delivering with noncoplanar isocenter beams. 13 patients treated with one target,47 patients treated with multi-targets.60 patients who were treaded with SRT received a mean dose of 54.7±6Gy with a 4～8Gy/f,3f/w,qod regimen,the dose were divided 6～12times.

单靶点X-SRT治疗13例，多靶点X-SRT治疗47例，每次分割剂量4～8Gy，照射6～12次，每周3次，隔日1次，1 中心参考剂量线定在90%，2个中心参考剂量线定在50%～80％，肿瘤剂量42～48Gy。

Geometric methods developed herein to obversely and inversely calculate the parameters of rational Bézier circular arcs with degrees of three and four are simple, practical and have direct geometric meaning.

所给算法具有几何直观性、简单、实用，符合计算机辅助几何设计的要求。

A semicomplete multipartite digraph is obtained by replacing each edge of a complete multipartite graph by an arc or by a pair of two mutually opposite arcs.

用一条弧或一对方向相反的弧代替完全多部无向图的每一条边所得到的有向图被称为是半完全多部有向图。2002年L。

This class of deposits is characterized by the abundance of iron oxide in the ores and the associated intensive regional sodic alteration. They may occur in Proterozoic intracraton or Phanerozoic continental margin volcanic arcs with nearby intrusive complex or evaporite. The spatially and temporally associated intrusive rocks are magnetite-series granitoids. Mineralization mainly occurs in second order echelon structures near the main regional structure.

该类矿床以矿石中含有大量的铁氧化物且伴有很强的区域性钠质蚀变为特征，可以产于元古代克拉通内或新生代大陆边缘岛弧环境，其周围具火成岩或含蒸发盐层，时空上与之有关的侵入岩为磁铁矿系列花岗岩，矿化主要产于近区域主断裂的羽状次级断裂中。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。