Abstract: The invention refers to a method for initializing the computation of a quasi-periodic steady state of a multi-tone system, and to a computer program product for carrying out such a method. The method for initializing the computation of a quasi-periodic steady state of a multi-tone system comprises the following steps: (a) selecting a first one of the plurality of tones, and (b) performing a transient analysis over several periods with respect to the first selected tone, while keeping all periodic input sources of the multi-tone system with frequencies that are not multiples of the first selected tone constant. Afterwards, a single-tone Fourier transform of the results of the transient analysis is performed.

Abstract: The invention refers to a method for initializing the computation of a quasi-periodic steady state of a multi-tone system, and to a computer program product for carrying out such a method. The method for initializing the computation of a quasi-periodic steady state of a multi-tone system comprises the following steps: (a) selecting a first one of the plurality of tones, and (b) performing a transient analysis over several periods with respect to the first selected tone, whilst keeping all periodic input sources of the multi-tone system with frequencies that are not multiples of the first selected tone constant. Afterwards, a single-tone Fourier transform of the results of the transient analysis is performed.

Abstract: A DC transfer curve of a circuit is determined for determining the global dynamics of a circuit and a stability analysis is conducted for points of the DC transfer curve. The results of the stability analysis are at least one stable region and at least one unstable region of the DC transfer curve. This makes it possible to determine sensitivity, speed and process tolerance of the circuit.

Abstract: A transfer function is formed starting from a technical system described by a system of parameter-dependent differential algebraic equations. Subsequently, information about the number of turns per unit length and about the monotonicity behavior of this transfer function is derived. It is established by using this information whether a Hopf bifurcation point is present. In the case of the presence of a Hopf bifurcation point, the latter is determined.

Abstract: A technical system is defined by a system of differential algebraic equations, and has periodically stationary solutions. The periodically stationary solutions are defined by setting up a homotopy equation which links a fixed point equation to a trivial equation, and by following a solution path of the homotopy equation from a start point to a target point by successively determining points of the homotopy equation.

Abstract: An electrical circuit having an oscillator and additional structural elements that are connected to the oscillator. In an iterative method, upon variation of circuit parameters of the additional structural elements, the following steps are carried out for each instance of the circuit parameters: a stability analysis of the circuit is carried out for each respective instance, and if the circuit oscillates, a first value is assigned to the instance in a matrix in which all the instances being examined are stored. Otherwise, a second value is assigned to the instance in the matrix.

Abstract: A liquid cooled, heavy duty resistor including a housing and a resistor element. The resistor element is arranged inside a chamber defined by the housing. The resistor element and the housing form a rectangular duct through which a cooling liquid flows from an inlet to an outlet. The chamber is defined by two insulating plates and an insulating ring. The resistor element is a bifilar wound spiral strip conductor and is clamped between two insulating plates such that the cooling liquid flows through the rectangular duct. The liquid cooled, heavy duty resistor can remove a high dissipated power in a small space, has low inductance, and has a low resistance value.

Abstract: In a spinning rotor for an open end spinning unit, the rotor being provided with a bore extending along its axis of rotation to accommodate a yarn extraction tube and being formed to define a fiber collection trough and an intake portion whose cross section widens in the direction toward the trough, the intake portion presenting a radially outwardly extending projecting portion which merges into and defines one boundary of the fiber collecting trough, the region where the projecting portion merges with the trough constituting the region of maximum diameter of the trough and the side of the trough opposite the projecting portion being defined by the spinning rotor bottom surface, the accumulation of dirt in the fiber collection trough is prevented by forming the collection trough so that the radially outermost end of the surface of the projecting portion defines the maximum diameter of the trough, imparting to the portion of the trough adjacent the rotor bottom surface a configuration such that the diameter of

Abstract: In an open-end spinning unit having a spinning rotor presenting an entrance opening, a break-up roller mounted for rotation coaxially with the spinning rotor and having a frontal end section at the end thereof directed toward the spinning rotor, the frontal end section being generally enclosed by the portion of the spinning rotor defining its entrance opening, and a housing enclosing at least part of the break-up roller, there is further provided, in order to improve the guidance of fibers into the fiber collecting trough of the spinning rotor, a fiber collecting ring located between, and coaxial with, the spinning rotor and the break-up roller, and supported by the housing, the fiber collecting ring protruding axially, in the direction away from the spinning rotor, beyond the frontal end section of the break-up roller and, in the direction toward the spinning rotor, beyond the entrance opening of the spinning rotor, with the inner surface of the fiber collecting ring facing the break-up roller and serving at

Abstract: In an open-end yarn spinning unit, a break-up roller which is driven by transmission of driving force from the spinning rotor, without mechanical contact between the roller and the rotor, is subjected to a speed regulation by application of a retarding force without mechanical connection between the roller and the source of each retarding force.

Abstract: An open-end spinning machine system containing a plurality of spinning units, the components of each unit including a spinning turbine, a breakup roller, a feed roller, a yarn extraction device and yarn wiping apparatus, is controlled during stopping and subsequent restarting by an automatic control system which is operated by switching members in such a manner that, during stopping of the system, the turbine, feed roller, yarn extraction device and winding device of each unit are first permitted to decelerate in unison, in a free rundown manner while the rotating speeds remain within the range permitting yarn spinning to continue, and these components are positively braked only when their speeds approach the lower limit of such range, while during restarting of the system, the yarn extraction device and the yarn winding device of each unit are caused to rotate through a selected distance in the direction opposite to their normal operating direction for feeding a fixed length of yarn back into the associated