Numerical semigroups problem list

We propose a list of open problems in numerical semigroups.Comment: To appear in the CIM Bulletin, number 33. (http://www.cim.pt/) 13 page

LFV in semileptonic τ\tau decays and μ−e\mu-e conversion in nuclei in SUSY-seesaw

Here we review the main results of LFV in the semileptonic tau decays $\tau \to \mu PP$ ($PP = \pi^+ \pi^-, \pi^0 \pi^0, K^+ K^-, K^0 \bar{K}^0$), $\tau \to \mu P$ ($P = \pi, \eta, \eta^{\prime}$), and $\tau \to \mu V$ ($V = \rho, \phi$) as well as in $\mu-e$ conversion in nuclei within SUSY-seesaw scenarios, and compare our predictions with the present experimental boundsComment: Talk given by M. J. Herrero in SUSY08 conference, Seou

Percepción de esfuerzo, diversión y aprendizaje en alumnos de educación secundaria en las clases de Educación Física durante una Unidad Didáctica de CrossFit

This research aims to know the enjoyment, learning and intensity level perception in Physical Education lessons during a CrossFit Educational Component and the relationship among gender and educational level. In order to that, a total of 104 secondary students whose ages vary from 12 to 16 years old have filled in two questionnaires about enjoyment, learning and effort perception. The results have shown high levels of enjoyment, effort and learning perception in the students thought CrossFit practice. Thus, boys perceive higher enjoyment and intensity than girls, and it has found that students in upper secondary perceive physical education lessons as more intense and less fun.Esta investigación pretende conocer la percepción de diversión, aprendizaje y nivel de intensidad de las clases de Educación Física durante una Unidad Didáctica de CrossFit y su relación con el género y el nivel educativo. Para ello, un total de 104 estudiantes de Educación Secundaria de entre 12 y 16 años completaron dos cuestionarios de percepción de diversión, aprendizaje y esfuerzo. Los resultados obtenidos han mostrado unos valores altos de percepción de diversión, esfuerzo y aprendizaje en los estudiantes a través de la práctica de CrossFit. Por otro lado, los chicos perciben una mayor diversión e intensidad que las chicas, y se ha encontrando que los alumnos de segundo ciclo de secundaria perciben las clases de Educación Física como más intensas y menos divertidas

CPS: 3D Compositional Part Segmentation through Grasping

Abstract—Most objects are composed of parts which have a semantic meaning. A handle can have many different shapes and can be present in quite different objects, but there is only one semantic meaning to a handle, which is “a part that is designed especially to be grasped by the hand”. We introduce here a novel 3D algorithm named CPS for the decomposition of objects into their semantically meaningful parts. These meaningful parts are learned from experiments where a robot grasps different objects. Objects are represented in a compositional graph hierarchy where their parts are represented as the relationship between subparts, which are in turn represented based on the relationships between small adjacent regions. Unlike other compositional approaches, our method relies on learning semantically meaningful parts which are learned from grasping experience. This compositional part representation provides generalization for part segmentation. We evaluated our method in this respect, by training it on one dataset and evaluating it on another. We achieved on average 78 % part overlap accuracy for segmentation of novel part instances. Keywords-Compositional model, 3D object representation, object part segmentation, graspability I

Triplet Exciton Generation in Bulk-Heterojunction Solar Cells based on Endohedral Fullerenes

Organic bulk-heterojunctions (BHJ) and solar cells containing the trimetallic nitride endohedral fullerene 1-[3-(2-ethyl)hexoxy carbonyl]propyl-1-phenyl-Lu3N@C80 (Lu3N@C80-PCBEH) show an open circuit voltage (VOC) 0.3 V higher than similar devices with [6,6]-phenyl-C[61]-butyric acid methyl ester (PC61BM). To fully exploit the potential of this acceptor molecule with respect to the power conversion efficiency (PCE) of solar cells, the short circuit current (JSC) should be improved to become competitive with the state of the art solar cells. Here, we address factors influencing the JSC in blends containing the high voltage absorber Lu3N@C80-PCBEH in view of both photogeneration but also transport and extraction of charge carriers. We apply optical, charge carrier extraction, morphology, and spin-sensitive techniques. In blends containing Lu3N@C80-PCBEH, we found 2 times weaker photoluminescence quenching, remainders of interchain excitons, and, most remarkably, triplet excitons formed on the polymer chain, which were absent in the reference P3HT:PC61BM blends. We show that electron back transfer to the triplet state along with the lower exciton dissociation yield due to intramolecular charge transfer in Lu3N@C80-PCBEH are responsible for the reduced photocurrent