Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

A model and an algorithm for the grouping problem in telecom networks

This paper deals with the so called grouping problem which arises in telecommunication network optimization when transmission equipment with a certain hierarchy is used. It is shown how this problem is embedded in the complete scheme of network optimization and a general combinatorial model is developed to derive afterwards a solution procedure. The implementation of this procedure forms part of a software tool for the complete problem of transmission network planning. Some results deriving from practical examples and further extensions are indicate

Un modelo y un algoritmo para el problema de agrupamiento en redes de telecomunicaciones

This paper deals with the so called grouping problem which arises in telecommunication network optimization when transmission equipment with a certain hierarchy is used. It is shown how this problem is embedded in the complete scheme of network optimization and a general combinatorial model is developed to derive afterwards a solution procedure. The implementation of this procedure forms part of a software tool for the complete problem of transmission network planning. Some results deriving from practical examples and further extensions are indicated

Un modelo y un algoritmo para el problema de agrupamiento en redes de telecomunicaciones

This paper deals with the so called grouping problem which arises in telecommunication network optimization when transmission equipment with a certain hierarchy is used. It is shown how this problem is embedded in the complete scheme of network optimization and a general combinatorial model is developed to derive afterwards a solution procedure. The implementation of this procedure forms part of a software tool for the complete problem of transmission network planning. Some results deriving from practical examples and further extensions are indicated

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Summary in EnglishAvailable from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, D-21400 Kiel W 208 (169) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman