A direct elimination algorithm for quasi-static and dynamic contact problems

This paper deals with the computational modeling and numerical simulation of contact problems at Unite deformations using the Finite element method. Quasi-static and dynamic problems are considered and two particular frictional conditions, full stick friction and frictionless cases, are addressed. Lagrange multipliers and regularized formulations of the contact problem, such as penalty or augmented Lagrangian methods, are avoided and a new direct elimination method is proposed. Conserving algorithms are also introduced for the proposed formulation for dynamic contact problems. An assessment of he performance of the resulting formulation is shown in a number of selected benchmark tests and numerical examples, including both quasi-static and dynamic contact problems under full stick friction and frictionless contact conditions. Conservation of key discrete properties exhibited by the time stepping algorithm used for dynamic contact problems is also shown in an example. (C) 2014 Elsevier B.V. All rights reserved.Peer ReviewedPostprint (author’s final draft

Patenting and research and development : a global view

Using a new global data base on patents and innovation inputs, the authors examine the process of knowledge creation measured by the dynamic relationship between research and development and U.S. patents granted. They confirm at the country level the recurrent micro-level finding of a strong relationship between the two and estimate the OECD elasticity to be effectively equal to one. This conflicts with the frequent micro-level finding of strongly diminishing returns in knowledge generation and suggests the importance of knowledge spillover effects measurable only at the aggregate level. Developing countries, however, do show diminishing returns. The authors then explain the differences in spillovers between the OECD and developing countries by testing for the impact of measures of the functioning of the national innovation system-the set of institutions and agents that create and disseminate knowledge. Across the entire sample education, security of intellectual property rights, and in some specifications, the quality of research institutions and their interaction with the private sector, affect the transformation of research and development into patents.Scientific Research&Science Parks,Science Education,Economic Theory&Research,Real&Intellectual Property Law,Technology Industry

Supporting task creation inside FPGA devices

The most common model to use co-processors/accelerators is the master-slave model where the slaves (coprocessors/ accelerators) are driven by a general purpose cpu. This simplifies the management of the accelerators because they cannot actively interact with the runtime and they are just passive slaves that operate over the memory under demand. However, the master-slave model limits system possibilities and introduces synchronization overheads that could be avoided. To overcome those limitations and increase the possibilities of accelerators, we propose extending task based programming models (like OpenMP [1] or OmpSs) to support some runtime APIs inside the FPGA co-processor. As a proof-of-concept, we implemented our proposal over the OmpSs@FPGA environment [2] adding the needed infrastructure in the FPGA bitstream and modifying the existing tools to support creation of children tasks inside a task offloaded to an FPGA accelerator. In addition, we added support to synchronize the children tasks created by a FPGA task regardless they are executed in a SMP host thread or they also target another FPGA accelerator in the same co-processor

FARM ADVISORY SERVICES AND PESTICIDE TOXICITY ON COTTON AND PEANUTS IN THE ALBEMARLE-PAMLICO WATERSHED

According to a Virginia-North Carolina watershed survey, farmers view advisory services as having the effect of decreasing pesticide use. However, analysis of pesticide use shows that hired staff, scouting personnel, and extension agents are associated with higher pesticide toxicity applied to cotton while chemical dealers and scouting personnel are associated with higher toxicity applied to peanuts.Crop Production/Industries, Environmental Economics and Policy,

On the Felsenthal power index

The paper that introduces the Felsenthal index is titled: ‘A well-behaved index of a priori P-Power for simple n-person games.’ In 2016, Felsenthal introduced his index for simple games. His definition does not base on the axiomatic approach. Then, Felsenthal regarded some properties and proved that his index satisfies a list of six reasonable and compelling postulates. Three of the properties that he regarded refer to the weighted games, but this fact does not reduce the definition of his index to weighted games. He proves that none of seven well-known efficient power indices proposed to date satisfies the list of postulates, indicating for each of them which of the six postulates violate. In this paper we extend some of his postulates, originally defined for weighted games, to simple games. The main objective of the article is to answer three open questions motivated in his article. In particular, we prove that his index may not be the unique one fulfilling the six proposed postulates, provide an axiomatic characterization for his index and, propose an impossibility result, which is obtained by adding a new postulate to a sublist of the postulates he considered. We also remark the existence of some alternative compelling postulates which are not satisfied for the index.This research is part of the I+D+i project PID2019-104987GB-I00 supported by MCIN/AEI/10.13039/501100011033/. We thank José María Alonso-Meijide for his comments and suggestions, which helped us to improve the manuscript. We greatly appreciate the comments of two referees that have contributed to improve this work.Peer ReviewedPostprint (published version

Probabilistic power indices for games with abstention

S'introdueixen vuit índexs de poder que admeten una interpretació probabilística per les normes de votació amb abstenció o amb tres nivells d'aprovació en l'entrada. S'analitzen les semblances i diferències entre els índexs estàndards coneguts pels jocs simples i per les extensions per aquest context més general. Es conclou la feina proporcionant procediments basats en la generació de funcions per jocs(3,2) extensibles a jocs (j,k).Preprin

First approach to a materialist interpretation of Argentinian history: "Contributions to cultural history in Argentina" of Germán Avé- Lallemant (1890)

El “padre” del marxismo argentino fue un inmigrante alemán: el agrimensor e ingeniero de minas Germán Avé-Lallemant (1835-1910). En 1890, Lallemant ofreció un análisis materialista pionero de la historia de su país adoptivo, que analizaba las causas del atraso argentino. Las razones que explican el estancamiento nacional se remontarían a la herencia retrógrada de la colonización española y a su supervivencia en la clase dominante local. Esta edición crítica de dicho estudio, inédito hasta hoy en castellano, se propone contribuir a la superación de visiones estereotipadas sobre el marxismo de Lallemant y de la Segunda Internacional.The "father" of Argentinian Marxism was a German immigrant: the land surveyor and mining engineer Germán Ave-Lallemant (1835-1910). Lallemant wrote in 1890 a pioneering materialist analysis of Argentine history that sought to understand the causes of Argentinian backwardness. The reasons for national stagnation would go back to the retrograde inheritance of Spanish colonization and their perpetuation in the local ruling class. This critical edition of that document, which so far remained untranslated, is intended to contribute to the overcoming of stereotyped visions of Lallemant´s and the Second International´s Marxism.Fil: Bosch Alessio, Constanza Daniela. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones y Estudio sobre Cultura y Sociedad; ArgentinaFil: Gaido, Daniel Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones y Estudio Sobre Cultura y Sociedad; Argentina. Universidad Nacional de Córdoba; Argentin

Performance analysis of a hardware accelerator of dependence management for taskbased dataflow programming models

Along with the popularity of multicore and manycore, task-based dataflow programming models obtain great attention for being able to extract high parallelism from applications without exposing the complexity to programmers. One of these pioneers is the OpenMP Superscalar (OmpSs). By implementing dynamic task dependence analysis, dataflow scheduling and out-of-order execution in runtime, OmpSs achieves high performance using coarse and medium granularity tasks. In theory, for the same application, the more parallel tasks can be exposed, the higher possible speedup can be achieved. Yet this factor is limited by task granularity, up to a point where the runtime overhead outweighs the performance increase and slows down the application. To overcome this handicap, Picos was proposed to support task-based dataflow programming models like OmpSs as a fast hardware accelerator for fine-grained task and dependence management, and a simulator was developed to perform design space exploration. This paper presents the very first functional hardware prototype inspired by Picos. An embedded system based on a Zynq 7000 All-Programmable SoC is developed to study its capabilities and possible bottlenecks. Initial scalability and hardware consumption studies of different Picos designs are performed to find the one with the highest performance and lowest hardware cost. A further thorough performance study is employed on both the prototype with the most balanced configuration and the OmpSs software-only alternative. Results show that our OmpSs runtime hardware support significantly outperforms the software-only implementation currently available in the runtime system for finegrained tasks.This work is supported by the Spanish Government through Programa Severo Ochoa (SEV-2015-0493), by the Spanish Ministry of Science and Technology through TIN2015-65316-P project, by the Generalitat de Catalunya (contracts 2014-SGR-1051 and 2014-SGR-1272) and by the European Research Council RoMoL Grant Agreement number 321253. We also thank the Xilinx University Program for its hardware and software donations.Peer ReviewedPostprint (published version