引入线

The flow properties of the polypropylene and polyethylene were studied using Archimedes spiral and square spiral melt fluidity test molds, which had the same shape of cross section but different cavity profiles, and then relationship between melt flow ratio and cavity profile was analyzed.

摘 要：对聚丙烯和聚乙烯 2种塑料在阿基米德螺旋线与方形螺旋线流动性测试模具中的流动性能进行研究，分析塑料流动比与型腔轮廓特征的关系；引入修正系数β，对流动比校核公式进行修正。

Based on the analysis of the mechanism of robot manipulators, a trajectory tracking controlling research model is first built up with ADAMS, and its mathematical model is formulated through the study of robot kinematics and dynamics. After the modeling errors are analyzed in practical robotic systems, a conception of centralized error is brought forward according to the theory of weighting functions. In the case of modeling errors' exist, the robotic uncertain model is derived by introducing an auxiliary control variable into inverse dynamic analysis. The control strategy of robust exponential convergence is applied to the robotic uncertain model, the applicable conditions and the applicable controller with this application are presented. The stable control effect under three main model uncertainties (parametric errors, joint disturbs, joint frictions) are systematically studied on the previously built research model. The problems of robust exponential convergence controller which often results in unstable output and so produces a large relative error when the input trajectory is in a small range are resolved by adjusting the control parameters based on the controller's structure.

本文在机械手的机械结构分析基础上，利用ADAMS建立了用于机械手轨线跟踪控制研究的机械手模型；通过对机器人运动学和动力学问题的研究，建立了机械手研究的数学模型；分析了机器人系统中模型误差的主要来源，根据加权函数法分析，提出了模型集中误差的概念；在存有模型误差的情况下，采用逆动力学结构并引入辅助控制量，由机器人误差模型推导了机器人非确定性模型；提出了采用鲁棒指数收敛法对上述机器人非确定性模型进行鲁棒镇定的控制策略，并给出了对机器人进行鲁棒指数收敛控制时系统不确定因素应满足的匹配条件；针对机械手研究模型，深入研究了鲁棒指数收敛控制器对机器人系统中常见的模型参数误差、关节扰动、关节摩擦等不确定因素的镇定控制效果；针对鲁棒指数收敛控制器易产生控制量振荡的问题以及在小范围内系统轨线跟踪的稳态误差过大问题，本文分别提出了基于控制器结构的控制参数调整法和基于轨线跟踪范围大小的控制参数分段切换法。

In this paper we combining connecting tunnel project of Subway Line 4 at Xidan-lingjing bystreet in Beijing. To aim at the difficulties of building large-span connecting tunnels in the fine sand layer, through roads and underground pipelines, construction nearby buildings and other project difficulties. Using theoretical analysis, numerical simulation, field tests and other research methods to comprehensive and systemic research the stratum deformation mechanism and process control techniques of shallow excavation method, and a series of results were obtained. Firstly, use the stochastic media theory to analyze the stratum deformation mechanism, concretely analyze the analytic equation of surface horizontal displacement and deformation which were caused by the excavation of single-hole and double-hole tunnel, and further discussion on ground settlement, vertical deformation, surface horizontal displacement and horizontal deformation. Analyzing the main influence factors of surface displacement, and combined with practical work to proof the theory which was applied to shallow buried single-hole tunnel in fine sand layer was scientific.

本文结合北京地铁四号线西单～灵境胡同渡线隧道工程，针对在粉细砂地层中修建大跨渡线隧道，下穿道路和地下管线，临近建筑物施工等工程难点，利用理论分析、数值模拟、和现场监测等多种研究手段，对浅埋暗挖隧道地层变位机理及控制技术，深入地进行全面和系统的研究，并取得以下成果：(1)引入随机介质理论，对地层变位机理进行了分析，具体分析了单、双孔隧道开挖引起的地表位移及变形的解析方程，并深入探讨了地表沉降、垂直变形、地表水平位移和水平变形的特点，同时分析了影响地表位移的主要因素，并结合工程实例，佐证该理论应用于粉细砂地层浅埋暗挖单孔地铁隧道的科学性。

A calibration model was established by introducing a planar target that could move freely with three collinear and known mutual location points. The calibration point coordinates in a camera coordinate system could be calculated by using the imaging information of three points and the light stripes on image plane of the camera.

引入一个可自由移动的平面靶标，靶标上只需要共线且相互位置确定的3个特征点，利用共线三点建立三点透视数学模型，根据3个特征点以及光条纹在摄像机像面的成像信息，获取了光平面上标定点在摄像机坐标系下的坐标。

In order to fully consider the topology relationship between anchor nodes and between anchor nodes and unknown nodes, we introduce the concept of collinearity and apply it into the localization of the multihop networks, and a Collinearity-Based Localization Algorithm is proposed.

为了充分考虑锚节点之间以及锚节点与未知节点之间拓扑关系对无线传感器网络定位精度的影响，我们引入了共线度的概念并将其应用到多跳网络的节点定位中，在此基础上提出了一种基于共线度的无线传感器网络定位算法。

Therefore, the 'generalized velocity unit' was introduced on the assumption that the surface velocity in the direction perpendicular to the line is a steady velocity frame with the topographic relief. The 3-D tomostatics velocity inversion was improved to suit the crooked wide line geometry.

为此，在假设垂直测线方向上表层速度是随地形起伏的稳定速度结构的情况下，引入"广义速度单元"概念，对三维层析静校正速度反演过程加以改进，使其适合宽、弯线资料观测系统。

Control wiring trunking has ample space and cover board. Nearside wiring trunking is used to introduce and educe the wiring between switchgears, starboard wiring trunking is used to lay intramural wiring in switchgear.

控制线线槽空间宽裕，并有盖板，左侧线槽用来引入和引出柜间连线，右侧线槽用来敷设开关柜内部连线。

Analyses the air handling process of cold air distribution system with outdoor air introduced to machine room directly or after being handled to the state of indoor air enthalpy.Presents in detail the drawing steps of the air state points in psychrometric chart for the air conditioning unit with blowing-through type fan.

分析了低温送风空调系统在新风直接引入和新风集中处理至室内空气状态点的等比焓线后引入空调机房两种情况下的空气处理过程，详细给出了空调器采用压出式风机配置时的焓湿图绘制步骤。

Because of the convolving effect between auto-tracking filter and the comb filter, the narrow linear band, multi wavelength optical fiber laser is acquired.3、A design of introducing a polarizer into the Michelson cavity is presented, which lead to further improvement of the coherent combinative effect. Moreover, the necessity to introduce such a polarizer is analyzed qualitatively in theory.

进而利用二者之间的卷积效应，研制中一种新颖的窄线宽多波长的光纤激光器。3、提出在Michelson式结构中引入起偏器，使激光相干合成效果得到了进一步的提高，而且从理论上定性分析了引入起偏器的必要性。

The results of calculation show that these algorithms are succinct, efficient, accurate, reliable, and they can accomplish the optimal design of integrated layout and connection scheme with high intelligence.Adopting the sectionalized lumped parameter method with dynamic friction, the dynamic performances of the typical segments in lineweb, i.e.

作为校验线网性能约束的后续环节，本文引入包含动态摩擦的管路分段集中参数键合图模型，对集成块线网中存在的短管、直角拐弯、分支管路、工艺孔容腔等典型结构进行分析，建立起具有典型结构的线网的分段集中参数键合图模型，并通过数字仿真和物理实验得到验大连理工大学博士学位论文证。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷