查询词典 vector field
- 与 vector field 相关的网络例句 [注:此内容来源于网络,仅供参考]
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In studying the linear response of the dressed quark propagator in the presence of the variable external field, we derive a general expression for the vacuum susceptibility, based on the two-point external field formula in the Quantum Chromodynamical sum rule. The expressions we have derived for the calculation of vacuum susceptibility are model independent. Then we use the expressions to calculate the renormalised axial vector, vector and tensor vacuum susceptibilities.
接下来在研究夸克传播子在外场中的线性响应时,我们利用QCD求和规则两点外场公式推导出了一般的计算真空磁化率的公式(以变化的轴矢量外场为例),我们这里推导出的真空磁化率的计算公式是模型无关的。
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An elliptic rotating field is produced when an induction motor operates in asymmetry, this paper proposes a model of jointed motion to describe the motion of an elliptic rotating vector and states that the elliptic rotating vector is jointed with two components, the main one rotates forward at a uniform speed while the adjunctive one jointed at the topend of the main one rotates backward around the joint point at a double speed, both make the elliptic rotating vector rotate at swinging amplitude, speed and direction.
感应电机不对称运转时产生椭圆旋转磁场,本文建立了描述椭圆旋转矢量的接合运动模式,说明椭圆旋转矢量是由一个主矢量带动一个付矢量一起旋转构成的接合矢量,主矢量以匀速旋转,付矢量链接在主矢量顶端同时绕着链接点相对主矢量以二倍速反向旋转,两者共同构成的一个单向椭圆旋转矢量。
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The main contributions of the second part of this dissertation are focused on the cryptographic properties of logical functions over finite field, with the help of the properties of trace functions, and that of p-polynomials, as well as the permutation theory over finite field: The new definition of Chrestenson linear spectrum is given and the relation between the new Chrestenson linear spectrum and the Chrestenson cyclic spectrum is presented, followed by the inverse formula of logical function over finite field; The distribution for linear structures of the logical functions over finite field is discussed and the complete construction of logical functions taking on all vectors as linear structures is suggested, which leads to the conception of the extended affine functions over finite field, whose cryptographic properties is similar to that of the affine functions over field GF (2) and prime field F〓; The relationship between the degeneration of logical functions and the linear structures, the degeneration of logical functions and the support of Chrestenson spectrum, as well as the relation between the nonlinearity and the linear structures are discussed; Using the relation of the logical functions over finite field and the vector logical functions over its prime field, we reveal the relationship between the perfect nonlinear functions over finite field and the vector generalized Bent functions over its prime field; The existence or not of the perfect nonlinear functions with any variables over any finite fields is offered, and some methods are proposed to construct the perfect nonlinear functions by using the balanced p-polynomials over finite field.
重新定义了有限域上逻辑函数的Chrestenson线性谱,考察了新定义的Chrestenson线性谱和原来的Chrestenson循环谱的关系,并利用一组对偶基给出了有限域上逻辑函数的反演公式;给出了有限域上随机变量联合分布的分解式,并利用随机变量联合分布的分解式对有限域上逻辑函数的密码性质进行了研究;给出了有限域上逻辑函数与相应素域上向量逻辑函数的关系,探讨了它们之间密码性质的联系,如平衡性,相关免疫性,扩散性,线性结构以及非线性度等;讨论了有限域上逻辑函数各类线性结构之间的关系,并给出了任意点都是线性结构的逻辑函数的全部构造,由此引出了有限域上的"泛仿射函数"的概念;考察了有限域上逻辑函数的退化性与线性结构的关系、退化性与Chrestenson谱支集的关系;给出了有限域逻辑函数非线性度的定义,利用有限域上逻辑函数的非线性度与相应素域上向量逻辑函数非线性度的关系,考察了有限域上逻辑函数的非线性度与线性结构的关系;利用有限域上逻辑函数与相应素域上向量逻辑函数的关系,揭示了有限域上的广义Bent函数与相应素域上的广义Bent函数的关系,以及有限域上的完全非线性函数与相应素域上向量广义Bent函数之间的关系;给出了任意有限域上任意n元完全非线性函数存在性与否的完整证明,并利用有限域上平衡的p-多项式的性质给出了有限域上完全非线性函数的一些基本构造方法。
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Maxwell's equations group in fact was already found in the basic experimental laws of electromagnetic phenomena, as well as a single magnetic pole does not exist on the facts and the integrated displacement current assumptions, using an international system of units, these equations can be written as: DivDW =ρ or DW =ρ(1) kiDivBq = 0 or Bq = 0 (2) kiCurlEBq =- Zt or × EqkZ =- BqZt (3) ZCurlHDWDW = jE Zt, or × HW = jE Zkt (4) Z-type in the Curl, and Div were vector operator curl and divergence, Micro-k points for the Hamiltonian operator, in the rectangular coordinate system,= iZZEkx jEy kqz, iE, jE, kq along Zx, y, z-axis unit vector, a vector for any AW are × AW = CurlAW, kAW = DivAW; DW for the electric displacement, Bq for the magnetic induction intensity, Eq, and HW, respectively i field and electric field strength, jY for the conduction current density,ρ the charge density for free.
麦克斯韦方程组实际上是当时已发现的电磁现象的基本实验定律以及单个磁极不存在的事实和位移电流假设的综合,采用国际单位制,这些方程式可写成:DivDW=ρ或DW=ρ(1)kiDivBq=0或Bq=0(2)kiCurlEBq=-Zt或×EqkZ=-BqZt(3)ZCurlHDWDW=jE+Zt或×HW=jE+Zkt(4)Z式中Curl和Div分别为矢量算符旋度和散度,为哈密顿微k分算符,在直角坐标系中,=iZZEkx+jEy+kqz,iE,jE,kq是沿Zx、y、z轴的单位矢量,对任一矢量AW有×AW=CurlAW,kAW=DivAW;DW为电位移,Bq为磁感应强度,Eq和HW分别为电i场和磁场强度,jY为传导电流密度,ρ为自由电荷密度。
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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。
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A mathemetical model of magnetic field in electromagnetic separation of inclusions from molten aluminum under rectangle coil and 50Hz current is presented according to the magnetic vector potential integral equation and the basic theory of magnetohydrodynamics. The magnetic field distribution in the gap of coils is simulated by the model and the actual magnetic field distribution also is measured. The experimental results show that the magnetic field distribution in the gap of coils is uniform and is consistemt with the model simulation. The magnetic field designed accord the simulated result is proved suitable in the practice.
摘 要:根据电磁流体力学的基本理论,利用矢量磁位积分,建立了在采用矩形电磁线圈和工频电源的条件下电磁分离铝熔体中夹杂的电磁场数学模型,模拟计算了电磁感应线圈气隙中的磁场分布状态,同时对制做的感应线圈的实际磁场进行了测量模拟计算磁场的分布状态与实际磁场的测量结果基本一致,都表明在电磁感应线圈气隙中磁场分布均匀,可以进行分离铝熔体中的非金属夹杂。
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The Nusselt number increased slightly then dropped down quickly with the increase of magnetic strength in the plane of the magnetic field vector; while in the plane perpendicular to the magnetic field vector, the Nusselt number decreased with the increase of the magnetic strength.
在平行磁场平面内,努塞尔数先随着磁场的增强略有增加,在强磁场作用下又迅速减小;在垂直磁场的平面内,努塞尔数随磁场增强逐步减小。
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This invention concerns a current control process for a feed-in voltage converter, wherein a detected flux-inducing current component and a detected torque-inducing currrent component of an actual currrent vector of a rotating field machine are each controlled for a flux-inducing current component set value and a torque-inducing current component set value of the rotating field machine. To that effect, a control set-value (DELTA u*sp, DELTA u*sq) is determined, dependent each time upon a determined current component control deviation. From these, current components of an actual current vector are formed each time by overlay of a formed pilot value (u*spvor, u*sqvor). This invention also concerns a device for carrying out this process.
本发明涉及一种用于馈入电压式变流器的电流调节方法,其中分别将所检测的一感应式电机的一实际电流向量(i s 的磁通感应电流分量和一转矩感应电流分量i sq )调节至该感应式电机的一额定电流向量的一磁通感应分量额定值和一转矩感应电流分量额定值,在这种情况下,分别根据所检测的一电流分量调节偏差计算出一调节器调节量(△u * sp ,△u * sq ),由这两个调节器调节量分别通过叠加所形成的一预控制量(u * spvor ,u * sqvor )形成一额定电压向量的电压分量(u * sp ,u * sq ),本发明还涉及一种用于实施该方法的装置。
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The speed-sensorless vector control and the identification of motor parameters in this paper are the two novel research of vector control.Using asynchronous machine's mathematic model in three-phase static reference frame, this paper has derived it's mathematic model in two-phase static reference frameand in two-phase rotating reference frame, and got the coordinate transformance formulus based on the constant magnetic force and power force, by compared different field orientation methods, we can find that field orientation at rotor field can realize the decoupling of the stator current flux component
无速度传感器矢量控制和电机参数辨识是矢量控制的两个新的研究方向,本文利用异步电机在三相静止坐标系下的数学模型推导出两相静止坐标系、两相同步旋转坐标系下的数学模型,根据磁动势守恒和功率守恒的原则,得出各坐标变换公式;通过不同磁场定向方式的比较发现,异步电机按转子磁场定向时定子电流励磁分量和转矩分量可以比较方便地实现解耦。
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On CHE programming, the higher coupling ratio of control-gate makes the higher electrical field across TOX in Si than Ge. Also because of the continuity of displacement vector, the higher permittivity of Ge would cause the lower electrical field at interface. We get the higher gate current in Si than Ge. On CFN programming, the higher CT in Ge would show the higher electrical field across TOX. However, the parameters of F-N tunneling are calculated and showing the gate current in Si is larger than Ge. On the same mechanism of F-N tunneling erasing, the parameters also show the higher electrical filed of Si would cause the higher erasing speed. The continuity of displacement vector also explains the higher electrical field at interface for F-N tunneling programming/erasing.
从通道热电子穿隧写入的模拟结果发现,由於控制闸极耦合电容的影响,加上电位移向量在半导体-氧化层界面连续的观念,拥有较高介电常数的锗反而得到较小的等效电场,决定了穿隧电流反倒是不如矽基板;在F-N穿隧写入的模拟中,即便锗基板拥有较大的总耦合电容,使得在浮闸的耦合电压大於矽基板,但仍旧是半导体-氧化层界面的电场扮演了穿隧电流的决定性因素,得到的结果仍旧是矽基板的写入速度高於锗基板;在F-N抹除的模拟中,运用与F-N写入相同的数学模型,仍旧看见在锗基板上未能得到速度上的改善,同时用数学的计算展示了合理的解释。
- 推荐网络例句
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We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.
索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称;三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起,称之为挽歌体诗人或者史诗诗人,他们被称为诗人,似乎只是因为遵守格律写作,而非他们作品的模仿本质。
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The relationship between communicative competence and grammar teaching should be that of the ends and the means.
交际能力和语法的关系应该是目标与途径的关系。
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This is not paper type of business,it's people business,with such huge money involved.
这不是纸上谈兵式的交易,这是人与人的业务,而且涉及金额巨大。