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The mass fragmentation pattern of thiones is also discussed.


Two compounds were designed, synthesized, and characterized by 1Hnuclear magnetic resonance (1HNMR), ultraviolet (UV)visible, and matrixassisted laser desorption/ionization (MALDI) mass spectra.


For two important special cases of mass action incidence and standard incidence, global stability of the endemic equilibrium is proved provided the threshold is larger than unity.


In this paper, a method has been established and validated for screening and identification of individual as well as total BFA by highperformance liquid chromatography and liquid chromatography/electrospray mass spectrometry in fungal raw materials.


Their structures were identified by nuclear magnetic resonance and mass spectrum.

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 In this paper the general synthesis problem of optimal control systems with the criterion of transient responses as a positive integral functional (3) is discussed.In the first part it is assumed that the motion of controlled object is described by a system of ordinary differential equations and that the final states of the system form a bounded and closed convex region in ndimentional euclidian phase space. A method is proposed for finding all optimal control functions which lead any starting state into the... In this paper the general synthesis problem of optimal control systems with the criterion of transient responses as a positive integral functional (3) is discussed.In the first part it is assumed that the motion of controlled object is described by a system of ordinary differential equations and that the final states of the system form a bounded and closed convex region in ndimentional euclidian phase space. A method is proposed for finding all optimal control functions which lead any starting state into the given final region of states. Some conclusions are obtained from the maximum principle by using transversal conditions of optimal trajectories in terminal points, and the particular properties of the stated problem are pointed out. The case of linear differential equations with integral quadratic functional criterion is investigated in detail.Further, in the second part the fundamental properties of isoloss regions, the relations between the isoloss region and optimal control functions are indicated. As a direct result a partial differential equation determining the optimal lossfunction J (x) is found and the connection between function J (x)and optimal vector control function u (x) is also stated. The methods proposed are practically the extension of the methods used by us for designing time optimal control systems as seen in [5, 6 ,7].Finally, an example is illustrated with optimal trajectories shown in phase plane.The necessary numerical data is calculated by an analog computer with high accuracy.  文中研究了具有公式(3)表示的一般正积分泛函的最优控制系统的综合问题.在第一部分中研究了具有控制参数的一阶微分方程组.控制系统的终点状态为n维相空间内的某一逐段光滑边界的闭性区域Ω.文中指出了根据极大值原理和轨道终点的横截条件寻找引到Ω的所有最优轨迹的方法.这里详细地研究了具有二次泛函和被积函数中不明显含有控制参数的质量指标泛函的线性方程情况.在文中第二部分研究了等损耗区的主要特性.指出了等损耗区与最优控制函数之间的关系.导出了求算最优损耗函数J(x)的偏微分方程,以及这一函数与最优控制函数u(x)的关系.上述方法是我们曾在文献[5,6,7]中用过的最优快速系统的综合方法的推广.文章最后举有例证.  This paper presents an investigation of the"Automatic Operator" of Diesel Locomotive based on the principle of compound programming control. According to the surrounding conditions of locomotive, the"Automatic Operator"can change its structure automatically in order to obtain better quality of control.In this paper, the principle scheme, the characteristics of"Automatic Operator" and the experimental results of automatic control of Diesel locomotive with "Automatic Operator"are presented, the principle and... This paper presents an investigation of the"Automatic Operator" of Diesel Locomotive based on the principle of compound programming control. According to the surrounding conditions of locomotive, the"Automatic Operator"can change its structure automatically in order to obtain better quality of control.In this paper, the principle scheme, the characteristics of"Automatic Operator" and the experimental results of automatic control of Diesel locomotive with "Automatic Operator"are presented, the principle and the design of logical circuit for changing the characteristics of"Automatic Operator"is emphasized. The latter part of the paper includes a discussion of quality of control; and finally, formulas for determining the parameters of the control system are derived.  文内介绍了采用复合控制原理和根据机车所处客观条件自动切换系统结构的内燃机车程序控制方案,介绍了按此方案制成的(自动司机)总体线路及其性能.介绍了利用这台控制机进行内燃机车自动驾驶的全面试验结果.文中着重讨论了自动切换系统结构的逻辑装置的设计计算.给出了综合这类系统参数的计算公式.此外,对系统的控制质量进行了详细讨论.  Equations determining the velocity and density distributions within the mixing region of two incompressible gases with different densities are set up, their temperatures being assumed to be the same. For incompressible mixing the total number of gas molecules per unit volume is constant, although the density of the gaseous mixture varies from point to point due to diffusion of matter. As an illustration we consider the plane jet and steady motion. The boundary layer method of approximation can still be applied.... Equations determining the velocity and density distributions within the mixing region of two incompressible gases with different densities are set up, their temperatures being assumed to be the same. For incompressible mixing the total number of gas molecules per unit volume is constant, although the density of the gaseous mixture varies from point to point due to diffusion of matter. As an illustration we consider the plane jet and steady motion. The boundary layer method of approximation can still be applied. The boundary of the jet is shown to be the same as that for one fluid. The solution of the problem then depends upon the numerical value of the coefticient of viscosity of the mixture which is a function of the number of molecules of each constituent gas in the unit volume. The present method of investigation is applicable to the cylindrical and half jets and also to the case where the two gases are at different temperatures.  本文求出规定二不能压缩气体的分片合流运动时,速度与质量密度分布的微分方程式。假定两种气体的密度不同但温度则相等。不能压缩的定义是每单位体积中的两种气体分子数的和不变。本文只讨论一平面守恒注中所需要的微分方程式。粘滞流体运动中之边界近似法仍可应用。同样方法亦可用到守恒圆柱体注,半注及气体中温度不同诸问题。   << 更多相关文摘 
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