在此中
- 与 在此中 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Finally, it is suggested that the study on content and structure in amylopectin and infusibility amylase would benefit to a better understanding in the effect of storage on the starch characteristics and rice grain quality.
在此基础上,提出加强储藏过程中稻米中支链淀粉和直链淀粉中不溶性组分的含量及其结构变化等的研究,将有利于解析储藏过程中稻米淀粉特性的变化及其对稻米品质的影响。
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This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component. For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper. For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space state informatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision. Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.
本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上,使用非流形几何模型作为理想材料零件几何拓扑模型的基础,并在半边数据结构基础上,针对理想材料零件的非流形特征局限内部边界上的特点,给出了一个半面数据结构来表述零件的几何拓扑信息;对于理想材料零件的材料模型,本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手,将材料信息表述为(n-1)维单纯形,然后通过对三维几何区域的单纯剖分,以插值的方式表述零件材料分布特征;在此基础上,根据功能梯度材料零件分层制造中对CAD数据处理的要求,给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法;而对于文中所定义的理想材料零件,本文将其材料信息表述分解到细观和宏观两个尺度进行,首先给出了细观尺度上参数化的周期性功能细结构概念,以此来统一表述功能梯度材料(单质材料作为特殊的功能梯度材料看待)、复合材料和功能细结构材料;把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组,以表达零件的细观材料特征;对于零件宏观的材料变化特征,则同样在几何区域单纯剖分的基础上,通过对细观尺度上周期性功能细结构控制参数的插值来完成;通过理想材料零件CAD数据处理的算例,验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。
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This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component.For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material .distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper.For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space stateinformatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision.Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.
本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上,使用非流形几何模型作为理想材料零件几何拓扑模型的基础,并在半边数据结构基础上,针对理想材料零件的非流形特征局限内部边界上的特点,给出了一个半面数据结构来表述零件的几何拓扑信息;对于理想材料零件的材料模型,本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手,将材料信息表述为(n-1)维单纯形,然后通过对三维几何区域的单纯剖分,以插值的方式表述零件材料分布特征;在此基础上,根据功能梯度材料零件分层制造中对CAD数据处理的要求,给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法;而对于文中所定义的理想材料零件,本文将其材料信息表述分解到细观和宏观两个尺度进行,首先给出了细观尺度上参数化的周期性功能细结构概念,以此来统一表述功能梯度材料(单质材料作为特殊的功能梯度材料看待)、复合材料和功能细结构材料;把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组,以表达零件的细观材料特征;对于零件宏观的材料变化特征,则同样在几何区域单纯剖分的基础上,通过对细观尺度上周期性功能细结构控制参数的插值来完成;通过理想材料零件CAD数据处理的算例,验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。
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As a result, the model of low-frequency aberration induced by Nd:glass amplifiers is got. On the base of low-frequency aberration model some results are achieved such as the tendency of focal spot size changing as the RMS phase gradient changes and the characteristics for the scale length. 3. The simulation model of the beamline is set up and the propagating process is analyzed in the beamline. The correlation coefficient of two wavefronts is newly used to describe and estimate the adding result of them.
建立了求空间尺度的数学模型,并运用此模型对现有的放大片透射波前进行了分析,得出了多程系统中所用钕玻璃放大片引入的低频位相误差的空间尺度分布,并据此建立了模拟放大片低频位相误差的随机位相屏模型,在此基础上对焦斑大小随位相分布RMS梯度变化而变化的规律及空间尺度的特性进行了模拟研究; 3。
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On this paper, the pulse electrochemical compound finishing technology parameters which influence the finishing surface roughness was paid attention to, such parameters include the pulse frequency, the duty factor, the peak voltage, the finishing time and so on. Then basic craft rule of two kinds of mold material in finishing process were obtained, and each kind of parameter in this craft was optimized by means of the orthogonal experiments.
在此基础上,重点考察了脉冲电化学复合光整加工过程中各工艺参数对光整后表面粗糙度的影响,如:脉冲频率、占空比、峰值电压、光整时间等,由此获得了这两种模具材料在整个过程中的基本工艺规律,并通过正交试验对光整加工中的各参数进行优化。
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No report about the analogous object in meteor ite has been seen, The mineral constituents of the vein are quartz, muscovite, illite (which was discovered firstly in meteorites), chlorite and some opeque minerals.
有关类似物质在其它陨石中的报道尚未见到。这条脉中的矿物组成有石英、白云母、伊利石(此矿物第一次被发现在陨石中)、绿泥石和一些不透明矿物。
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To solve the exsisting problems in the realization of the LFM/CW radar, the thesis presents a technique for dynamically measuring the LFM/CW signals, which can accomplish the dynamic measurements of FM linearity, FM bandwidth and FM slop of the transmitted signals of LFM/CW radars. This technique creates an effective and accurate means of judging the performance of LFMCW radars. The linearity-correction techniques presented in the thesis successfully make the linearity of the transmitted signals of an actual LFM/CW radar reduce from approximately 25% to 0. 1%(or r. m. s linearity of 0.04%), better than the best results (0.22%) obtained by foreign researchers with complex linearization closed-loop in the same kind of LFM/CW radars, according to the published literatures during the last decade. In order to improve the capability of the real-time processing and range-cells management of LFM/CW radars, the principle of equivalent mixing by lacking-sampling process of band-pass real signals is proposed based on the well-proved improvedversion of sampling theorem of band-pass real signals. This principle is used to configure the range-segments processing of the beat signals of an actual LFM/CW radar. The techniques of system-background interference suppression and the beat signal's dynamic range suppression are proposed, and are realized in an actual LFM/CW radar to demonstrate their effectiveness.
针对线性调频连续波雷达实现中急待解决的技术问题,文中提出并验证了线性调频连续波信号的综合动态测试技术,可以完成对线性调频连续波雷达发射信号的扫频线性度、扫频带宽和扫频斜率的综合动态测试,为衡量实际线性调频连续波雷达的系统性能创立了精确有效的测试手段;文中建立的非实时闭环动态校正技术使一部实际的线性调频连续波雷达的发射信号(时带积3×10〓)的扫频线性度从25%改善为0.1%(方均根线性度0.04%),优于国外已公布的80年代同类雷达中采用复杂的实时闭环动态校正环路所获得的实际结果(0.22%);为了改善线性调频连续波雷达的实时性和分辨单元数处理能力,文中发展完善了实带通信号的采样定理并给予了严格证明,并在此基础上提出了欠采样等效混频原理,将其应用于实际线性调频连续波雷达的距离分段处理中;针对线性调频连续波雷达中系统背景干扰和回波动态范围问题,创立了系统背景综合抑制技术和频域动态范围压缩技术,并将它应用于实孔线性调频连续波雷达系统中,显示出它们的有效性。
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In studies of interaction among pile, platform that above it and surrounding soil, this paper employ the concept of plate element to simulate the loading character of platform, and employ the concept of solid element to simulate the character of pile and soil, using the finite element method after understanding the geometry properties of pile, soil and the platform. Analyzing the loading properties of the three entities above and their deformation, this paper also employ a special element, Penalty Element. The introduction of penalty element of this kind has served to guarantee the join harmony of displacement between solid element and plate element, thereby effectively resolving the join problem between platforms, pile that support it and surrounding soil.Considering significant property difference between pile material and its surrounding soil, there may be much shear stress on their contact interface produced under vertical load, thus causing displacement or fission. Therefore it is necessary to adopt one special constitutive law of this kind of contact interface, which can reflect its feature of loading and deformation thoroughly. On the basis of the deformation feature and constitutive laws of some contact interface obtained by Zhang Dongji and people concerned through some single-shear experiments on contact interface between structure and soil, this paper employ one pile-soil three-dimensional constant thickness contact interface model to simulate the " slide" taken place on the interface between pile and its surrounding soil. With this kind model, this paper has also created one finite element model, which can be applied to perform finite element calculation and analyze the pile-loading feature, and deduced its element stiffness matrix.
在承台-桩-土共同作用中,考虑桩与承台的几何特性,采用有限元方法,用实体单元模拟桩土,用板单元模拟承台,更具体地分析桩和承台的受力特性和变形,而且还采用罚单元—既实体单元与板单元之间连接必须满足变形协调条件,来有效地解决了承台与桩土的连接问题,且在桩土共同作用中,由于桩体结构的材料性能与周围土层性质相差较大,在竖向荷载下有可能在其接触面上产生较大的剪应力从而导致错动或开裂,因此,为了充分反映桩土接触面上的受力及变形特征,应采用一种桩土接触面特有的本构关系,即利用张冬霁等人关于结构与土体接触面单剪试验所得到的接触面变形特征及其本构关系,引入桩-土三维等厚度接触单元来模拟桩与桩侧土之间的&滑移&,在此基础上建立可用于桩基承载性状分析的有限元计算单元模型,并推导出了各单元的刚度矩阵。
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Basing on this, this paper proposes a generalized shortest path method. That is, by constructing an intermodal-network multi-ply graph which interrelates the data and information in transit with the nodes and sides of the graph, adding virtual origin and destination stations to the graph, and then analyzing transport costs and transfer costs, this paper applies the Dijkstra algorithm to solve the intermodal optimal transport path problem so as to get the intermodal transport plan with the least generalized costs.
在此基础上,提出一种求解最佳运输路线的广义最短路法,即通过构建多式联运网络多重图,将运输过程中的数据、信息和图中的节点、边关联起来,然后对运输费用和中转费用进行分析估计,并通过在联运网络图中加入虚拟的发、到站,使得该问题可用Dijkstra算法进行求解,从而获得广义费用最少的联运方案。
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It is also possible to reduce this phenomenon by using SPP adjustment controls.
可以采用A模式,用较小的F值来拍摄,可以减轻此现象。在SPP中调整也可以减轻此现象。
- 推荐网络例句
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Do you know, i need you to come back
你知道吗,我需要你回来
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Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.
1〕 杨银书,王祥生,李德昌。安徽省首次发现嗜群血蜱。
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Chapter Three: Type classification of DE structure in Sino-Tibetan languages.
第三章汉藏语&的&字结构的类型划分。