查询词典 numerical system

Summary: This system imbeds the multi-axis motion controller PMAC card into PC to constitute open numerical control system applied in horizontal twin spindles double column drill press, using the software of the PMAC card, and the software and the hardware resources of PC, this system complete the numerical control function for the horizontal twin spindles double column drill press, and incarnate the open character of the system adequately.

本系统采用多轴运动控制器PMAC卡嵌入PC机的模式，构成一种专门应用于双主轴龙门钻床的开放式数控系统，利用该卡配置的软件和PC机的软、硬件资源，使系统完成双主轴龙门钻床的数控功能，并充分体现系统的开放性。关键词：数控系统，PMAC，双主轴龙门钻床。

Summary: This system imbeds the multi-axis motion controller PMAC card into PC to constitute open numerical control system applied in horizontal twin spindles double column drill press, using the software of the PMAC card, and the software and the hardware resources of PC, this system complete the numerical control function for the horizontal twin spindles double column drill press, and incarnate the open character of the system adequately.

邬再新，吕洪波摘要：本系统采用多轴运动控制器PMAC卡嵌入PC机的模式，构成一种专门应用于双主轴龙门钻床的开放式数控系统，利用该卡配置的软件和PC机的软、硬件资源，使系统完成双主轴龙门钻床的数控功能，并充分体现系统的开放性。

The following exciting results are revealed: 1 When considering the influence of some nonlinear elements such as hard-limit of exciters, the effects of some devices such as Power System Stabilizer and Static Var Compensator which can introduce positive damping in power system, the reasonability of system parameter values in simulation, the SNB surface and HB surface on the boundary of SSSR will turn close to each other and even coalesce together; 2 Under some conditions, coupling between slow exciters and shunt capacitors will bring negative damping in power system dynamics, which increases the possibility of oscillatory instability. So the power system with mass shunt compensators is easily subjected to the oscillatory instability. In recent years, chaotic phenomena of power system have been reported many times. Some simulation studies even found chaos existing inside the power system SSSR. In this dissertation, chaotic phenomena in power systems are thoroughly studied in order to make clear the relation of chaos and SSSR. The following results are derived: 1 Based on Li-Yorke Theorem and their definition on the chaos, the existence of chaos in power system is verified; 2 Three possible routes of causing chaos in power system are found and deeply investigated. They are route of cascading period doubling, route of directly initial energizing and route of torus bifurcation (or quasi-periodicity). The latter two routes are investigated for the first time in power system stability studies; 3 When the stability conditions of chaos are broken, it is found they can lead to voltage collapse, angle divergence, or voltage collapse with angle divergence simultaneously.

针对在电力系统小扰动稳定区域内可能存在混沌吸引域的有关报道，本文深入研究了电力系统混沌现象的出现途径和与系统失稳模式之间的关系：1利用Li-Yorke定理和Li-Yorke的混沌定义，从理论上证明了电力系统混沌现象的存在性；2发现了电力系统中导致混沌出现的三种可能途径：倍周期分岔导致混沌、初始能量直接激发混沌和经由环面分岔导致混沌，并对后两种新发现的途径进行了较为细致的研究；3发现了混沌极限环破裂导致电压崩溃、角度失稳以及电压崩溃和角度失稳同时出现的现象，其中混沌极限环破裂导致系统角度失稳和电压崩溃及角度失稳同时出现的现象均属首次报道；4证明由微分-代数方程描述的系统模型，其小扰动稳定域的边界只包含HB、SNB和SIB三种分岔界面，在SSSR的内部和边界上，均不可能存在会导致混沌的点，从而将混沌现象排除在小扰动稳定域的研究之外，简化了后者的研究工作。

Factory remaining hot water, remaining vapor and boiler heating system, were adopted in tilapia overwintering. Every step, such as site selection, pond and fish preparation, cultivation of fish, fish selection, timing of overwintering, stocking density and managements during overwintering, was compared among three systems. The results of data analysis showed that the survival rate in remaining hot water system was 12% higher than in remaining vapor system and 21.25% higher than in boiler heating system. The overwintering cost in remaining hot water system was 735 Yuan/m~3, which was 18 Yuan lower than in remaining vapor system and 71.4 Yuan lower than in boiler heating system. The profit in remaining hot water system was 201 Yuan/m~3, which was 162 Yuan higher than in remaining vapor system and 275.4 Yuan higher than in boiler heating system.

本论文采取了余热水、余热气、锅炉加温三种方式对进行罗非鱼越冬保种，从地点选择、越冬池、鱼的准备、越冬苗种的培育、越冬前催肥、越冬鱼的选留、越冬鱼进池时间和密度、越冬期间饲养管理等环节进行对比试验获得了三种方式的试验数据并进行了分析讨论，结果显示：余热水越冬雌亲鱼的成活率比余热气越冬高出12％、比锅炉加温越冬高出21.25％；余热水越冬雌亲鱼的成本每立方米为735元比余热气越冬的成本每立方米低18元、比锅炉加温越冬的成本每立方米低71.4元；余热水越冬雌亲鱼的利润每立方米为201元比余热气越冬的利润每立方米高162元、比锅炉加温越冬的利润每立方米高275.4元。

As important ways for numerical solutions of partial differential equations, spectral methods have been developed rapidly in the past several decades. They not only have been widely applied to numerical simulations in various fields such as physics, mechanics, aerology, oceanics etc, and their theories of numerical analysis also tend to perfect.

作为数值求解的一种手段，谱方法在近几十年得到了蓬勃的发展，它不仅被广泛运用于物理、力学、大气、海洋等领域的数值计算，而且它的数值分析理论也不断地趋于完善。

The company produces the processing equipment to be advanced, check-out facility excellent, has the numerical control lathe, the numerical control drilling machine, the machining center, the numerical control gear-hobbing machine, the gear shaper, the fine borer, the universal milling machines, each kind of grinder, the table planer, the booklet bender, the large-scale lathe, the mechanical slicer, high intermediate frequency quenching, the well type, the box-type hardening furnace, the tempering furnace, the automatic welding machine, the X-ray crack detection machine, the cloth, the Rockwell tester; Electric hoist test platform, sound-level meter, varnish film thickness gauge, altazimuth, level; The material analysis laboratory, the metallography analysis room and so on full had guaranteed strictly the vehicle, the mill, dig, rub, pull, the boring, to drill, the ramming, cutting, the angle iron, the chemical examination and the heat treatment and so on complete technical process.

公司生产加工设备先进，检测设备精良，拥有数控车床、数控钻床、加工中心、数控滚齿机、插齿机、精密镗床、万能铣床、各种磨床、龙门刨床、折弯机、大型车床、刨床、高中频淬火、井式、箱式淬火炉、回火炉、自动焊机、 X射线探伤机、布、洛氏硬度计；电动葫芦试验台、声级计、漆膜测厚仪、经纬仪、水准仪；材料分析化验室，金相分析室等充分严格保证了车、铣、刨、磨、拉、镗、钻、冲压、切割、弯板、化验及热处理等全部工艺流程。

This thesis contributed to the comprehensive study of the Finite-Difference Time-Domain method and its application to the numerical computation of radiated electromagnetic fields in switched mode power supplies. The work includes mainly three parts: the study on the performance of PML absorbing boundary condition applied to pseudo low frequency electromagnetic problems; the validation of the FDTD method with PML absorbing boundary conditions and the corresponding computer software based on the numerical study of the electromagnetic field of an electric dipole antenna, and its application to the numerical computation of radiated electromagnetic fields in switched mode power supplies; the development of an improved alternating direction implicit finite-difference time-domain method.

在综合前人工作基础上，本文对时域有限差分法及其在开关电源辐射电磁场数值计算中的应用进行了系统的分析和研究，其核心内容包括：伪低频电磁场数值计算中PML吸收边界条件性能的研究；基于基准问题—电偶极子天线三维辐射电磁场，验证了本文构造的基于PML吸收边界条件的三维FDTD法及其计算软件，并应用于高频开关电源辐射电磁场的数值分析；提出了一种改进的交替方向隐格式时域有限差分法。

The unique advantage of this halfanalytical numerical method is that the analytical process of Conformal Mapping can transform an irregular area into a regular one such as a rectangle. Therefore, the discretization error of numerical methods on the boundary can be avoided, and the numerical algorithm can be implemented more easily, with the computing efficiency improved.

这种保角变换的半解析数值方法的突出优点是：利用前期的保角变换解析处理将不规则的场域转化为规则的矩形域，从而避免了纯数值技术对复杂边界的离散化误差，降低了后期数值计算的算法复杂度，并提高了计算效率。

Considering complicated conditions of the coastal dynamic environment, sediment dynamics, and together with the immature sediment itself, the predicted results will be somewhat limited if only with numerical model. So, in order to obtain microcosmic quantitative assessment and macroscopically understanding, numerical model is combined with field observations in the thesis. Firstly, the tidal current, SSC distribution, benthal deposited materials were basically analyzed by field observations. Then, the tidal current, SSC distribution, and the erosion and accumulation of the seabed were simulated with the numerical model of ECOMSED.

但由于海岸动力环境多变，泥沙运动复杂，加之泥沙问题本身的复杂性，如仅用数学模型，其预测结果将受到一定的限制，故本文采用实测调查与数学模型计算相结合的方法，宏观把握，微观量化，在掌握岚山港西突堤工程所在海域潮流、悬沙量分布、表层底质沉积物类型及特点基本态势的基础上，紧扣开发工程可能引起潮流场变化，分析工程后悬沙量、海底冲淤变化及其空间分布，进而建立潮流作用下的泥沙输运数学模型，首先比较好地模拟目前岚山港西突堤工程附近海域的潮流场和悬沙场，然后预测海湾沿岸可能引起的冲淤强度变化和冲淤区域的空间分布。

The proposed method has the merit that the numerical characteristics of stochastic temperature field response can be obtained by analyzing the random temperature field just in one time.3. Perturbed numerical algorithm of nonprobabilistic convex set theoretical models on the temperature fieldThe uncertain parameters of physical parameters and initial boundary conditions of heat conduction are described by the convex model. The perturbation formulas of the upper and lower bounds of temperature field response with unknown-but-bounded parameters are given via the combination of matrix perturbation theory and the convex set theory model.4. Numerical analysis for transient temperature field with interval parametersConsidering the uncertainties of the transient heat transfer, the physical parameters and initial boundary conditions are regarded as interval variables.

该方法具有只进行一次随机温度场分析便可以获得其响应的数字特征的优点。3、温度场的非概率凸集合理论模型的摄动数值解法将结构导热的物理参数、温度场的初始和边界条件等不确定性参数以凸模型加以描述，基于矩阵摄动理论和处理不确定问题的凸集合理论模型的结合，导出有界不确定参数瞬态温度场响应所在集合的上、下界摄动计算公式。4、具有区间参数的瞬态温度场数值分析考虑结构瞬态热传导问题的不确定性，将结构各物理参数和温度的初、边值条件均视为区间变量。

"Yes, now you can give yourself airs," she said, you have got what you wanted.

"对了，您现在高兴了，"她说道，这是您所期待的。

Then the LORD said to me: Rebel Israel is inwardly more just than traitorous Judah.

上主于是对我说：＂失节的以色列比失信的犹大，更显得正义。