Model Equation for the Dynamics of Wrinkled Shockwaves: Comparison with DNS and Experiments

International audienceA model equation for the dynamics and the geometry of the wrinkled front of shock waves, obtained for strong shocks in the Newtonian limit, is tested by comparison with direct numerical simulations and a shock tube experiment

Plant voedt bodem: Uit onderzoek blijkt dat planten belangrijker zijn voor het voeden van de bodem dan bemesting.

In de biologische landbouw wordt vaak gezegd dat je eerst de bodem moet voeden en dat zo vanzelf de plant wordt gevoed. Uit onderzoek komt echter steeds duidelijker naar voor dat de plant zelf een zeer belangrijke rol speelt bij het voeden van de bodem. Daarmee is de cyclus gewas>beworteling>bodemleven>bodem>gewas weer rond

Acoustical Excitation for Damping Estimation in Rotating Machinery

In experimental modal analysis a structure is excited with a force in order to estimate the frequency response function. Typically, this force is generated by a shaker or a hammer impact. Both methods have proven their usefulness, but have some well-known disadvantages. A main disadvantage of the shaker is that it has to be fixed to the structure whereas with a hammer it is not possible to excite a specific frequency. To overcome these disadvantages, alternative non-contact methods can be used. There are several non-contact techniques, i.e. pressurized air, laser, acoustics, etc. By using acoustics as an excitation technique it is easy to select an excitation signal going from random noise to a simple sine. Also the equipment to produce the acoustic excitation is rather cheap. However, the state of the art does not offer a straightforward technique to estimate the excitation force, making it difficult for applications such as experimental modal analysis. In this research, acoustic excitation is compared with hammer excitation to estimate the frequency response function of two shafts. Especially a method to validate the force induced by the acoustics is derived. The final purpose of this research is to estimate the damping properties of rotating machinery

Regional Sanctions Against Burundi: A Powerful Campaign and Its Unintended Consequences

This paper examines the impact of regionally imposed sanctions on the trajectory of the Burundian regime and its involvement in the peace process following the 1996 coup in the country. Despite the country's socioeconomic and geopolitical vulnerability, the Buyoya government withstood the pressure from the sanctions. Through a vocal campaign against these sanctions, the new government mitigated the embargo's economic consequences and partially reestablished its international reputation. Paradoxically, this campaign planted the seed for comprehensive political concessions in the long term. While previous literature has attributed the sanctions' success in pressuring the government into negotiations to their economic impact, the government actually responded to the sanction senders' key demand to engage in unconditional, inclusive peace talks under the auspices of the regional mediator once the economy had already started to recover. The regime's anti-sanctions campaign, with its emphasis on the government's willingness to engage in peace talks, backfired, with Buyoya forced to negotiate after having become entrapped in his own rhetoric

Tese: "Os audioguias na acessibilidade aos museus. A sua aplicação ao Museu da Ciência da Universidade de Coimbra"

Os audioguias na acessibilidade aos museus. A sua aplicação ao Museu da Ciência da Universidade de Coimbra Autora: Maria João Martins Pereira Neto Orientação: Pedro Júlio Enrech Casaleiro e Irene Maria de Montezuma de Carvalho Mendes Vaquinhas Dissertação apresentada no âmbito do 2º Ciclo em História, Especialização em Museologia, da Faculdade de Letras da Universidade de Coimbra. Júri: João Paulo Cabral de Almeida Avelãs Nunes (que presidiu); Pedro Júlio Enrech Casaleiro (orientador); Irene ..

MESURE DES PROBABILITES DE TRANSITION DES RAIES 51D2, 61D2, 71D2 → 51P1 DU CADMIUM

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