560 research outputs found
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
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LFV in semileptonic decays and conversion in nuclei in SUSY-seesaw
Here we review the main results of LFV in the semileptonic tau decays (), (), and () as well as in 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
Analysis Approach of How University Automotive Competitions Help Students to Accelerate their Automotive Engineer Profile
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
On Roth’s “human fossil” from Baradero, Buenos Aires Province, Argentina: morphological and genetic analysis
The "human fossil" from Baradero, Buenos Aires Province, Argentina, is a collection of skeleton parts first recovered by the paleontologist Santiago Roth and further studied by the anthropologist Rudolf Martin. By the end of the nineteenth century and beginning of the twentieth century it was considered one of the oldest human skeletons from South America's southern cone. Here, we present the results of an interdisciplinary approach to study and contextualize the ancient individual remains. We discuss the context of the finding by first compiling the available evidence associated with the historical information and any previous scientific publications on this individual. Then, we conducted an osteobiographical assessment, by which we evaluated the sex, age, and overall preservation of the skeleton based on morphological features. To obtain a 3D virtual reconstruction of the skull, we performed high resolution CT-scans on selected skull fragments and the mandible. This was followed by the extraction of bone tissue and tooth samples for radiocarbon and genetic analyses, which brought only limited results due to poor preservation and possible contamination. We estimate that the individual from Baradero is a middle-aged adult male. We conclude that the revision of foundational collections with current methodological tools brings new insights and clarifies long held assumptions on the significance of samples that were recovered when archaeology was not yet professionalized
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
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