查询词典 definite time

And an optimal operation strategy of any kind of products subject to spoilage at any time is obtained on the basis of the proposition of the model of distributed parameter control systems. Moreover, definite economic explanations to spatial adjoint function and control variables are presented.

通过建立可变质产品的最优经营管理的分布参数控制系统模型，得出了零售企业每个瞬间每种可变质产品的最优经营管理策略，并对空间伴随函数和控制变量给出了明确的经济学解释。

The results show that the glass-ceramics with fibroid structure is produced after definite heat treatment, the main crystallization phase is hedenbergite and anorthite is the minor crystallization phase. The optimal process of heat treatment shows as follows: the nucleation temperature is 850 ℃ and hold time is 100 min, and the crystallization temperature is 980 ℃ and hold time is 80 min. With increasing heat treatment temperature, the FT-IR absorption bands appear obvious split, the aluminum-oxide polyhedron in the glass network changes from [AlO4] to [AlO6]. The titanium ion in the glass network gradually transforms to the 6-coordinated, moreover forms minicrystal of MgTi2O5 and Fe2TiO4 which provides the position of heterogeneous nucleation for the growth of crystal.

结果表明：在一定的热处理条件下可以以基础玻璃制备出主晶相为钙铁透辉石，次晶相为钙长石的纤维状结构的微晶玻璃；最佳的热处理工艺为：850 ℃核化100 min，980 ℃晶化80 min；随着热处理温度的升高，红外吸收带发生明显的分裂；玻璃结构中的[AlO4]向[AlO6]转化；网络结构中的钛离子逐渐转变为六配位，形成微晶相——钛酸镁和钛铁晶石，为晶体的生长提供非均匀形核位置。

ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.

本论文针对车载异步电机在矢量控制器所遇到的问题：定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案：分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算，分析出对于电流型逆变器在采用定子磁场定向时，其性能同时具有矢量控制和直接转矩控制两者的优势，并对电压型逆变器在转子磁场定向下的模型进行了仿真研究；建立异步电机非线性模型，推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程，并做出了仿真结果，建立异步电机在非线性模型下的矢量控制调节器的PI参数设计，在实际应用中，若忽略电机电感的动态变化，可以根据当前的磁路饱和状态而在线修正电感参数，从而将非线性方程线性化，降低控制器的复杂度；考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出，本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题；推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通，用于实现高性能的矢量控制算法，并给出了仿真结果；推导出了电动汽车恒转矩给定的闭环回馈制动系统，实现了电动控制模型和制动模型的统一，而且结合铅酸电池最大充电电流的要求，为制动转矩在线给定建立了数学模型；设计了基于双DSP系统的高性能矢量控制器软硬件框图，并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。

Gave the concept of generalized positive definite matrices for the first time in 1970, the scholars, after 39 years' tough research, have put forward many more generalized positive definite matrix and acquired huge achievement.

首次给出广义正定矩阵的概念以来，学者们历经39年的艰苦研究历程，产生了许许多多更加广义的正定矩阵，获得许多丰富的研究成果。

The precis writer to solar eclipse is in the world the most entire having reached thousand time, and all there is the precis writer clear and definite in location to start-stop time.

对日食的记录是世界上最完整的达上千次，而且对于起止时间位置都有明确记录。

METHODS From January 1998 to February 2001, 4 ml of sodium hyaluronate injection was injected into the knee joint of the 134 cases at the end of arthroscope operation, or the 91 cases undergoing open operation of the knee at the time when the drain tube was removed. Five days after operation, the hydrarthrosis was removed and 2 ml of sodium hyaluronate was injected into the knee joint. According to the patient's condition, injection of sodium hyaluronate was performed once a week for several weeks. Clinical evaluation was made by evaluating pain visual analog scale and painless range of movement of the joint at every definite point of time.

1998年 1月～ 2 0 0 1年 2月，对关节镜手术 134例于手术结束时，以及膝关节开放手术 91例于术后 2 4小时拔引流管时，分别在关节腔内注射透明质酸钠 4ml ；术后第 5天抽出关节积液，再注入透明质酸钠注射液 2 ml；每周 1次，连续 5周为一个疗程，根据病情注射1～ 2个疗程，观察各时间点疼痛 VAS评分和达到最大无痛活动度的时间。

Prestack time migration is a key technology that can image steep dip angle formation and complex fault system. It yields accurate velocity field and definite fault compared to poststack time migration.

叠前时间偏移技术是一项解决地层倾角大、断层复杂成像的关键技术，可以求取准确的速度场，偏移后断层清晰。

As a natural result, the mass matrix is a positive definite consistent and time-independent one, and the two time-dependent and nonsymmetric matrice, that is, the "gyroscopic damping" and "centrifugal stiffness" ones, don't exist in the equation.

在不附加任何&运动学&假设的情况下，作为自然的结果，方程的质量阵是正定、协调的常数阵；方程中不存在两类时变的非对称系数项，即所谓的&陀螺阻尼&项和&离心动刚度&项。

In 5:1,"being justified" is in the aorist, or point, tense, indicating the definite time at which each person, upon the exercise of faith, was justified.

在5：1 ，&有道理&，是在aorist ，或点，紧张，同时标明确切时间，在每个人，一经行使信仰，是有道理的。

Where the contract is to insure the subject-matter at and from, or from one place to another or others, the policy is called a "voyage policy " and where the contract is to insure the subject-matter for a definite period of time the policy is called a "time policy".

1在保险合同承保保险标的&在和从&或&从&某一地点运送至另一地点或其他地点之场合，该保险单称作&航次保险单&；在保险合同承保保险标的某一段固定期间之情况下，该保险单叫做&定期保险单&。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。