查询词典 precision block

Countering the serious wear on plain bearing bush of the primary lathe axis supporting,and the reducing of working precision,change to the ball bearing ,thus increase the working precision of the product.

针对原车床主轴支承滑动轴承轴瓦严重磨损，加工精度降低，改用滚动轴承支承法，从而提高了产品的加工精度。

The results indicated:（1）the combination of the Markov and spatial logistic models can improve the predictability of each model individually. In macroscopic scale, the total land use amount can be predicted via Markov chain; in microscopic scale, the multi-class multinomial logistic model can be used to implement the combined calculations of categorical variable and continuous variable, qualitative variable and quantitative variable to improve the precision of spatial regression. Meanwhile, the transition probability of each land use unit will be confirmed and the prediction of land use spatial distribution will also be completed.（2）the application system developed in accordance with the integrated model can effectively simulate and predict the land use evolution in Shenzhen City, and the prediction precision of verification system will suffice for recent land use monitoring and the making of annual land supply planning.

研究结果：（1）空间Logistic和Markov模型集成可提升单一模型的应用能力，宏观上利用Markov Chain进行土地利用规模总量预测，微观上利用多分类Multinomial Logistic模型解决分类变量与连续变量，定性变量和定量变量的联合解算提高空间回归精度，同时可以确定每一个土地利用单元转移概率，实现土地利用空间分布的预测；（2）基于集成模型开发出的应用系统能够有效仿真和预测深圳市土地利用演化，通过验证系统预测精度能够满足近期土地利用预警和年度土地供应计划编制。

These days with there being the gap in the precision and the capability of numerical control machine between our country with international advance level, this paper puts forward the projet of multiple axes rotary spindle head structure on the foundation of setting up direct drive technology, in order to satisfy needs of exceed high speed cutting and exceed precision machining.

目前国产数控机床精度、性能与国际先进水平还存在一定差距，文中在建立了直接驱动技术概念的基础上，介绍了万能自动镗铣头结构方案，以满足超高速切削、超精密加工等先进制造技术的需要。

Theoretical analysis and simulation shows that the direction driving motor accelerates first, and then decelerates to compensate for the eccentricity when the satellite is deviated from laser center with a certain distance, and reacquires the tracking satellite. The needed time from reacquisition to tracking is affected by motor acceleration, telescope′s detecting precision, and detector′s response and treatment time, and the effect of detector precision on the reacquisition and re-tracking time is greater, as a result, the detector response and treatment time is decreased to the least.

理论分析与仿真结果表明，当卫星偏离光斑中心一定距离时，指向驱动电机先加速后减速，补偿这个偏心，重新捕获跟踪卫星；重新捕获到跟踪所需时间受电机加速度和望远镜探测精度以及探测器响应处理时间影响，其中探测器精度对重新捕获到跟踪所需时间影响较大，探测器响应处理时间要减小到最小；为了使从捕获到跟踪过程中卫星始终在扫描光斑范围内，经纬仪驱动电机的最小角加速度为25.5°/s2。

We have constant temperature experimental apparatus, ultrasonic cleaning machines, high-precision Abbe Refractometer calibration using modern high-precision equipment and testing instruments, has a number of professional and technical high, the practice of high-tech experienced team to forge a solid foundation for enterprise development.

本厂拥有恒温实验装置，超声波清洗机，高精度校准用阿贝折光仪等现代化高精设备和检测仪器，有一批专业技术高，实践经验丰富的高科技人员队伍，铸就企业发展的雄厚基础。

The advantages and limitations of every kind of methods for calculating the failure probability is reviewed. The frist order reliability method, the second order reliability method and many kinds of boundary method have achieved remarkable success and formed nature fields of reliability. However, the precision of these methods decrease as the increase of complexity of problem. The numrical methods are versatile, except numerical intergration is only adaptable to special problems which have small number variables and regular intergral domain. Particularly, the advanced variance reduction techniques own the following character: high precision and a small amount computation. But some questions remain to study in the future because only an initial work about these techniqes is developed.

全面评述了计算失效概率各种方法的优点和局限性，其中经典的解析法包括一次可靠性方法、二次可靠性方法、一阶边界法、Vanmarcke上边界、PENT上边界和Ditlevsen二阶窄边界法，这些方法对于多设计点、变量较多且相关、密度函数不是正态以及极限状态方程较复杂的情况，其计算精度较差；而已有的数值方法却是具有较好的通用性，其中除数值积分法只对变量较少、积分域较规则的特殊问题适用外，各种数值模拟方法均具有较广的适应性，特别是各种改进的方差减小技术，精度高、计算量小，但由于其处在研究的初级阶段，还有许多问题有待于解决。

In order to study the numerical method to solve the viscous incompressible flow with free surface, the 3-D mathematical model for steady and unsteady hydrodynamic problem had been established and closed by k-εbuoyant turbulence model. The algebraic coordinate transformation method was used to fit the free surface, the Runge-Kutta method of three step and second precision was devised to simulate the time step. A high precision up-winding compact scheme was studied for the convection term, and the generalized conjugate residual method was set to solve the Poisson equation.

为了研究粘性不可压缩三维问题的数值求解方法，本文从基本的Navier-Stokes方程出发，采用代数拟合方法处理自由表面，用三级二阶Runge-Kutta方法对时间步进过程进行了模拟，并且对对流项的高精度迎风格式进行了研究，给出了求解压力Poisson方程的广义共轭剩余法，从而建立了能够模拟有自由表面的粘性不可压缩问题的定常、非定常三维水动力学模型，并采用k—ε浮湍流模型对其进行封闭。

The measurement system error model analysis is introduced into power system real time network state analysis as an important part for the first time, which can improve on the state estimation quality and provide the capability to monitor the operation of the measurement system; 2. The theory and algorithm of the on-line estimation and update of measurement noise variance based on the relation between the residual variance and noise variance. The statistic properties of the sample variance are discussed and the relation between the estimation precision and sample size under given confidence level is derived; 3. The theory and algorithm of detection and identification of measurement bias are presented, which is based on the relation between residual mean and noise mean. The statistic properties of sample mean are discussed and the relation between estimation precision and sample size is derived; 4. The Givens orthogonal transformation algorithm is selected to be the essential algorithm of state estimation, the fast orthogonal transformation algorithm with damp factor and the algorithm which can handle the zero injection measurements efficiently are presented; 5. The quantity analysis theory of bad data detectivity and identifibility are presented, which describes the relation between the elements in matrix W〓 and bad data amplitude and can provide the theory base for measurement system design and valuation.

一、首次将量测系统误差模型分析做为一个环节引入电力系统实时网络状态分析中，为EMS系统增加了实时监视系统运行、修正量测系统误差模型的新功能，进一步发挥了实时网络状态分析应用软件的潜力；二、首次提出了应用样本方差在线估计与修正量测系统误差方差的基本理论，讨论了样本方差的统计性质和概率分布，推导出了样本容量、估计精度和置信度之间的关系，给出了在线估计与修正量测系统误差方差的算法；三、首次提出了应用样本均值在线检测与辨识量测偏差的基本理论，讨论了样本均值的统计性质，推导了样本容量、估计精度和置信度之间的基本关系，给出了在线检测与辨识量测偏差的算法；四、在状态估计算法设计中，以Givens变换算法做为基本算法，提出了快速正交变换阻尼因子法和可以有效地处理零注入量测的混合法，并对实时应用中的一些问题进行了讨论；五、提出了不良数据可检测性与可辨识性的定量分析理论，揭示了描述量测系统配置、网络结构与参数的残差灵敏度矩阵中的元素与不良数据的幅值在可检测、可辨识能力上的定量关系，为量测系统配置设计与评价提供了理论基础；六、综合国内外最新研究成果，采用自适应自回归预测技术和稀疏矢量技术，构造了较完善的不良数据检测与辨识算法。

Through the interferencing light intensity under a sine-wave modulation signal analysis, the output signal of fiber-optic gyroscope is demodulated. And then the change of the output signal of gyro is gotten. Through the analysis of the change we know that the effect of residuary intensity modulation on the performance of Interferometric Fiber Optic Gyroscope is related with the precision and accuracy requirements of IFOG. The higher precision, the more obvious effect.

本文首先通过正弦波调制下干涉信号光强分析解调出光纤陀螺的输出信号，进而得出残余强度调制存在的情况下陀螺输出信号的变化情况，同时，通过分析陀螺信号的变化说明残余强度调制对光纤陀螺性能的影响与陀螺精度要求有关，精度越高，其影响越明显。

A fast high precision multichannel MSC1210- based system for measurement of the coil resistance of electromotors is introduced in this paper. The fundamental of the system is discussed. The hardware and software designing as well as the major characteristics of MSC1210 is introduced. Better anti interference measures are considered in software and hardware designing to reduce the exterior influence. And the error analysis of the system is carried out. The system has the merits of high precision,low noise,strong anti interference,convenient operation and so on.

文章阐述了以一种新型单片机MSC1210为核心的多通道、高精度、快速测量电动机绕组电阻的测量系统及其基本原理，介绍了MSC1210单片机的主要特性及系统的硬件设计和软件设计，采用了软件和硬件抗干扰技术以减小外部干扰对系统的影响，并对该系统进行了误差分析，具有准确度高、噪声低、抗干扰能力强且操作方便等优点。

If you were not , and OS X just booted normally, have no fear.

如果你没有，和OS X刚刚启动通常，没有恐惧。

I only want to preserve our all .

我只想保存好我们的一切