Dynamic model of fracture

We study the failure properties of heterogeneous materials within the framework of the fiber bundle model subject to the global load-sharing rule in which the load failing elements is shared equally among all surviving elements. We develop a simulation technique by using the Langevin equation in order to investigate some characteristics of our model. It is found that the behavior of time to failure tf decreases with an exponential law and the avalanche size distribution present a power law.We study the failure properties of heterogeneous materials within the framework of the fiber bundle model subject to the global load-sharing rule in which the load failing elements is shared equally among all surviving elements. We develop a simulation technique by using the Langevin equation in order to investigate some characteristics of our model. It is found that the behavior of time to failure tf decreases with an exponential law and the avalanche size distribution present a power law

Localisation Intravésicale d’une Broche d’ostéosynthèse (A Propos D’un Cas)

La variété de corps étrangers introduits dans l’appareil génito- urinaire défie l’imagination et peut confronter l’urologue aux difficultés de leur extraction. Si leur présence relève souvent d’une pratique douteuse d’origine psychiatrique, il faut noter la possibilité d’une migration à partir des espaces perivésicaux lors d’une chirurgie de voisinage ainsi qu’une introduction accidentelle durantune intervention transvésicale. Les symptômes du bas appareil urinaire, non spécifiques, sont les circonstances fortuites de découverte de corps étrangers intravésicaux. Bien que le pronostic vital ne soit pas engagé, l’extractionchirurgicale ou endoscopique s’avère nécessaire du fait de l’inflammation sévère associée aux dommages vésicaux secondaires à ce corps étranger.Nous rapportons le cas d’un jeune patient admis aux urgences chez qui on trouve une broche d’ostéosynthèse compliquée d’une lithiase située dans la vessie

Klizni lom u modelu snopa vlakana

We study the creep rupture of fiber composites subjected to uniaxial constant load within the framework of the fiber bundle model. Our numerical studies show that in the primary creep, the deformation rate exhibits a power law relaxation followed by a power law acceleration in the tertiary creep. We also investigate the behavior of the failure time and the avalanche size distribution. A good agreement is found between experiments and the model prediction, particularly for deformation power-laws scaling in the primary-creep regime and in the tertiary-creep neighbourhood of rupture.Proučavamo klizni lom vlaknastog kompozita opterećenog stalnom jednoosnom silom primjenom modela snopa vlakana. Naša numerička istraživanja pokazuju da deformacije u početnom klizanju slijede potencijalni zakon, a u tercijalnom ubrzanje s drugim potencijalnim zakonom. Ispitujemo također vrijeme loma i raspodjelu jakosti lavine. Nalazimo dobro slaganje eksperimentalnih podataka s predviđanjima modela, posebice za sumjerenost potencijalnog zakona u početnim kliznim uvjetima i blizu tercijalnog kliznog loma

Klizni lom u modelu snopa vlakana

We study the creep rupture of fiber composites subjected to uniaxial constant load within the framework of the fiber bundle model. Our numerical studies show that in the primary creep, the deformation rate exhibits a power law relaxation followed by a power law acceleration in the tertiary creep. We also investigate the behavior of the failure time and the avalanche size distribution. A good agreement is found between experiments and the model prediction, particularly for deformation power-laws scaling in the primary-creep regime and in the tertiary-creep neighbourhood of rupture.Proučavamo klizni lom vlaknastog kompozita opterećenog stalnom jednoosnom silom primjenom modela snopa vlakana. Naša numerička istraživanja pokazuju da deformacije u početnom klizanju slijede potencijalni zakon, a u tercijalnom ubrzanje s drugim potencijalnim zakonom. Ispitujemo također vrijeme loma i raspodjelu jakosti lavine. Nalazimo dobro slaganje eksperimentalnih podataka s predviđanjima modela, posebice za sumjerenost potencijalnog zakona u početnim kliznim uvjetima i blizu tercijalnog kliznog loma

A discrete firefly algorithm to solve a rich vehicle routing problem modelling a newspaper distribution system with recycling policy

A real-world newspaper distribution problem with recycling policy is tackled in this work. In order to meet all the complex restrictions contained in such a problem, it has been modeled as a rich vehicle routing problem, which can be more specifically considered as an asymmetric and clustered vehicle routing problem with simultaneous pickup and deliveries, variable costs and forbidden paths (AC-VRP-SPDVCFP). This is the first study of such a problem in the literature. For this reason, a benchmark composed by 15 instances has been also proposed. In the design of this benchmark, real geographical positions have been used, located in the province of Bizkaia, Spain. For the proper treatment of this AC-VRP-SPDVCFP, a discrete firefly algorithm (DFA) has been developed. This application is the first application of the firefly algorithm to any rich vehicle routing problem. To prove that the proposed DFA is a promising technique, its performance has been compared with two other well-known techniques: an evolutionary algorithm and an evolutionary simulated annealing. Our results have shown that the DFA has outperformed these two classic meta-heuristics

L’absence segmentaire et congénitale de la veine cave inférieure: cause rare de l’hématurie macroscopique, à propos d’un cas

L'absence de la veine cave inférieure (VCI) est une anomalie congénitale peu fréquente, au retentissement clinique habituellement discret. Nous rapportons le cas d'un jeune homme de 19 ans, au passé de pesanteurs pelviennes chroniques, présente un épisode d'hématurie macroscopique chez qui l'échographie rénale a montré un hématome péri rénal. L'uroscanner puis l'angioscanner mettront en évidence un hématome périrénal et une agénésie segmentaire de la VCI dans sa portion sous rénale et une agénésie partielle de veine iliaque droite, avec drainage azygos et volumineux réseau de suppléance péri rénal. Nous rapportons le cas d'une agénésie du segment sous rénal de la VCI et de la veine iliaque droite

Dynamic model of fracture

1 Laboratoire de physique de la matière condensé