查询词典 control element

The basic approach of protecting people from being hurt or killed in an accident is to improve crashworthiness of vehicles. This paper starts with discussing theories and methods for vehicle passive safety design, which included experiential methods, analytic methods, multi-body dynamics methods, crash test methods and the finite element method. Emphasis will be paid to the basic FEM theories and algorithms of impact problems. Topics discussed include the governing equation, element discretization, hourglass control, time integration, material model, shell element algorithms and contact-impact algorithms. For more reliable simulation results, this paper then conducts study on how to accurately get material model parameters by combining the FEM method with experimental method, and develops relevant material test machine and parameter calculating software. Based on that, basic typical impact simulation and test validation study are conducted. On the basis of the above work, the paper studies the thin-shell structures'crashworthiness, which was affected by the following factors: spot-weld features, shell thickness, cross-section and pre-deformation. As to vehicle parts'crashworthiness, the paper conducts simulation study of designing energy-absorbing steering system and adaptive airbag system. A practical energy-absorbing steering wheel is designed as an example. In further depth research, the paper suggests several inverse quantificational methods for vehicle crashworthiness design based on the ideal crash characteristics. The above theories and methods are applied with good results through several practical vehicles' crashworthiness design and improvement.

文中对汽车碰撞安全性的设计理论和方法进行了归类和总结，其中包括经验法、解析法、多刚体动力学法、试验法以及有限元方法等；重点介绍了碰撞有限元法的基本理论和有关算法，涉及到有限元求解控制方程、单元离散、沙漏模态控制、时间积分、材料模型和应力修正、薄壳单元算法以及接触碰撞界面算法等，探讨了有限元计算中的材料模型参数获取技术，开发了相应的材料试验装置及材料模型参数反求软件，在此基础上进行了基本的碰撞仿真算例和试验对比研究；文中通过应用有限元方法研究了薄壁构件的碰撞吸能特性，指出了设计薄壁吸能构件时需要考虑的几个主要影响因素，即焊点、壁厚、横截面和预变形等；在关于车辆部件的碰撞安全性能设计中进行了吸能转向机构和自适应安全气囊的仿真研究，提出了吸能转向机构和自适应安全气囊的仿真研究方法；文中最后探讨了整车碰撞性能的设计与改进方法，提出了以理想碰撞特性为目标，采用分段加速度或者根据碰撞时间进行设计的反推设计法、部件吸能仿真优化设计法等量化设计方法，并通过综合应用文中所讨论的相关技术进行了整车碰撞性能的设计与改进实例研究，所选定的车型是大众化的普通轿车和碰撞安全性基础较差的微型面包车，研究结果表明，本文所提出的设计与改进方法是适用而有效的，具有重要的工程实用意义和价值。

To give the definition of the mass concrete and to concrete\'s cracks together with practical meanings of control ,and give a brief review on the research in the field at home and abroad, at last, methods to control temperature crack of the mass concrete from several aspects such as design measures,concrets material, construction schedules.etc are summed up; To explain the physical mechanics of the concrete and computing methods-Difference Method and Finite Element Method, and illustrate the application of their specific methods repectively;Several temperature factors that can influence the temperature stress of mass concrete baseplate are analyzed. The influence degree of temperature factor can be got through the ANSYS simulation computation the control of temperature can control the temperature stress, consequently control the temperature crack of mass concert baseplate; through the influence of the crack resistance ability of mass concrete baseplate which takes the reinforcement as a part is analyzed. By ANSYS simulation, the best suited volume ratio of reinforcement is found out, at same time the layout of reinforcement with the same volume ratio can also affect the resistance ability of mass concrete baseplate. Sum up of above analysis, anti-crack function of steel bar in early mass concrete baseplate is obvious, so it\'s necessary to consider beneficial effect of construction steel bar in research of temperature control on mass concrete baseplate.

本文先容了大体积混凝土及混凝土裂缝的基本概念，对国内外在这个领域里的研究现状作了扼要叙述，并从结构设计、混凝土材质、施工措施等方面总结了大体积混凝土温度裂缝控制的方法及防止措施；阐述了混凝土的基本物理力学性能，总结了大体积混凝土温度计算的方法——差分法和有限元法，并分别举例说明其具体应用的方法；分析了影响大体积混凝土底板温度应力的几种温度因素，利用ANSYS模拟计算，得出了每种因素的影响程度，通过分析提出了在这几种温度影响因素下如何通过控制温度以达到控制温度应力从而来控制裂缝的具体建议；针对大体积混凝土基础底板中配筋的不同对混凝土底板抗裂能力的影响不同，利用ANSYS进行模拟分析，得出底板中最合适的体积配筋率，同时分析了在相同体积配筋率下钢筋的具体布置对大体积混凝土基础底板抗裂能力的影响，分析表明，配置钢筋对混凝土结构的开裂阻止作用明显，在研究大体积混凝土温度裂缝题目时，要考虑钢筋在其中的有利作用。

In the beginning stage of the transient process in the system regulating, owing to that the time constant of the integration element is the greatest, the control effect of PID is inconspicuous, the main control action is the fuzzy control the practical control of the system is independent of the mathematical model of the object, a preferable control effect could be achieved for different kinds of systems.

在开始阶段的过渡过程中的制度规范，由于该时间常数的一体化因素是最大的，控制效果的PID是不显眼的，主要的控制作用是模糊控制的实际控制系统独立的数学模型的对象，最好的控制效果可以实现不同类型的系统。

The latter two all reckon that basic shape of line element error band based on control points error is "dumbbell-shape",i.e.error in control end points is larger than points error between two control points.

后两者均认为以控制点点位误差描述的线元的误差带的基本形状呈"哑铃"形，即认为线元上端点的位置不确定性大于端点之间的点的位置不确定性。

According to the fractional derivative model of viscoelastic damper and force-deformation-slip relation of friction element,a precise finite element model of FVD is constructed,and the method for forming element stiffness matrix and control force vector of FVD is deduced.

针对粘弹性材料的分数导数模型和摩擦单元的力-位移-滑移量的矩阵关系式，建立了FVD精确的有限元模型，推导了FVD单元刚度矩阵和控制力向量计算公式和求解方法；根据钢筋混凝土框架结构的非线性特性，建立了设置FVD非线性钢筋混凝土框架结构地震反应时程分析的控制方法。

Intelligent control strategys such as fuzzy control, all has the merit of not rely on the object mathematical model and the strongly robust, it can overcome the element of uncertainty in the servosystem such as parameter change and non-linear change, thus it can realize the high quality control performance of the system.

模糊控制等智能控制策略，都具有不依赖于对象的数学模型、鲁棒性强的优点，能够很好地克服伺服系统中模型参数变化和非线性等不确定因素，从而实现系统的高品质控制性能。

This paper deals with and summarizes the research and importance of ductile shear zones and presents the future direction and aim for the research of the ductile shear zones around the world. Four aspects of studies of the ductile shear zones have been proposed in this paper as follows:(1) The stress environment including the mineral assemblages, deformation, stress-shearing parameters;(2) The major element sequence and activation under condition of stress;(3) The variations of trace elements and REE, their transportation distributions under strong natural deformation as well as variations of mineral crystal parameters, which can also control the element changes during the ductile deformation;(4) The relationship between element migrations, activation and stress, which will present the new evidences for the studies of dynamic diagenesis and mineralization as well as the studies of evolution of ductile shear zones developed in middle and low levels.(5) The analysis of elements and isotopes in mylonites on the micro-scale are crucial for the understanding of component migrations during the mylonization.

对韧性剪切带及其变形岩石的研究现状和研究意义进行系统的综述，提出了未来韧性剪切带及其糜棱岩的研究方向和目标：①系统研究糜棱岩中主要造岩矿物组合及其变形特征，计算剪切变形岩石的应力－应变参数，搞清韧性剪切带所处的应力应变环境；②系统研究韧性剪切带岩石在天然分强剪切应力作用条件下常量元素迁移机制及活化转移的应力排序问题；③系统研究剪切变形作用过程中岩石化学组成的微量和稀土元素变化，讨论强变形条件下岩石中微量元素活化和迁移规律，深入探讨微量元素迁移的动力控制，包括稀土元素配分变化的应力制约以及应变矿物晶格化学变化行为及其对其寄主的变形岩石元素在应变过程中迁移变化的制约和影响；④从理论上探讨天然强剪切应变条件下岩石中组分活化、转移与应力的因果联系，为深入探讨韧性剪切带动力成岩作用提供理论的科学依据，为探讨中、下地壳中韧性剪切带的形成和演化提供科学依据，同时为韧性剪切变形作用条件下成岩、成矿地球化学作用提供理论和实验依据；⑤现代分析技术如激光同位素原位分析以及激光ICP-MASS分析技术对研究变形域内的岩石的元素和同位素的活化迁移规律，对深刻揭示糜棱岩化过程中的元素活化迁移机制提供更高质量的地球化学证据具有重要的作用。

More than ten years ago,"the negative day" the numerical control line cutting engine bed first applies and the actual production, starts the control bench is uses the transistor separative element assembly to become, after but uses the integrated circuit, now to is using the direction which the microcomputer controls to develop, Therefore this definition design "the electrical fire colored thread cutter automatic control" is by 8031 shrapnel machine took the control core, step-by-steps the electrical machinery achievement to actuate the electrical machinery, the diffraction grating a closed-loop control system which constitutes as the position examination part.

十多年前，&负旦型&数控线切割机床首先应用于实际生产，最早控制台是由晶体管分离元件组装而成，逐渐采用集成电路，现在正向采用微型计算机控制的方向发展，因此本论文设计的&电火花线切割机的电气控制系统&是以89C55单片机作为控制核心，步进电机作为驱动电机，光栅作为位移检测元件而构成的一个闭环控制系统。

The system uses PID controller and fuzzy controller to design automatic control loops, a study of fuzzy three-element feed-water control system for a CFB municipal waste incinerator is introduced. The incinerator is faced with problems such as large-scale fluctuation of furnace heat load and low regulation resolution of main control feed-water valve. The fuzzy logic control system is applied to modulate PI control parameters according to steam drum water level to fit fluctuated heat load, the inner and outer control loops are realized in an asynchronous way to effectively decrease regulation time and improve regulation precision.

针对垃圾炉炉膛负荷波动较大，同时给水调节阀门执行机构的调节精度较低的现状，在传统三冲量串级汽包水位控制方式的基础上，采用模糊控制策略对内、外串级回路的PI控制参数进行分区域调整，强调了PI参数在被控参量处于不同范围时的分离作用，同时内、外控制回路采用异步控制方式，浙江大学硕士学位论文从而有效地减小了被控参量的调节时间，提高调节精度，使水位波动控制在△为士12~范围内。

The water heater shall have a self-diagnostic control that monitors and indicates power on, no power or control failure, start-up failure, high-limit operation, sensor failure, defective upper element, or defective lower element.

这种热水器应该配置自诊断控制装置，能够监控和显示通电、停电、控制装置故障、启动故障、高温运行、感应器故障、上部加热元件或下部加热元件故障等状态。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了