687 research outputs found

    Models of relativistic particle with curvature and torsion revisited

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    Models, describing relativistic particles, where Lagrangian densities depend linearly on both the curvature and the torsion of the trajectories, are revisited in D=3 space forms. The moduli spaces of trajectories are completely and explicitly determined using the Lancret program. The moduli subspaces of closed solitons in the three sphere are also determined.Comment: 13 page

    Supersymmetry and Polytopes

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    We make an imaginative comparison between the Minimal Supersymmetric Standard Model and the 24-cell polytope in four dimensions, the Octacube.Comment: Presented to the Workshop on Geometry and Physics: Supersymmetry. Bilbao, Spain. May 200

    Gauge theory in dimension 77

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    We first review the notion of a G2G_2-manifold, defined in terms of a principal G2G_2 ("gauge") bundle over a 77-dimensional manifold, before discussing their relation to supergravity. In a second thread, we focus on associative submanifolds and present their deformation theory. In particular, we elaborate on a deformation problem with coassociative boundary condition. Its space of infinitesimal deformations can be identified with the solution space of an elliptic equation whose index is given by a topological formula.Comment: 15 page

    The Classification of Highly Supersymmetric Supergravity Solutions

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    The spinorial geometry method is an effective method for constructing systematic classifications of supersymmetric supergravity solutions. Recent work on analysing highly supersymmetric solutions in type IIB supergravity using this method is reviewed [arXiv:hep-th/0606049, arXiv:0710.1829]. It is shown that all supersymmetric solutions of IIB supergravity with more than 28 Killing spinors are locally maximally supersymmetric.Comment: 23 pages, latex. To appear in the proceedings of the Special Metrics and Supersymmetry conference at Universidad del Pais Vasco, May 2008. References correcte

    Distanciamiento social ante la COVID-19: Simulación del aforo máximo de personas mediante PHP

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    Population confluence in internal or external areas considerably increases transmission of COVID-19, due to not respecting the social distancing established by the health system. The objective of this work was to make use of programming techniques, using the PHP language (hypertext preprocessor), for the development of an application that simulates the maximum capacity of people who can enter an internal or external area. The methodology allowed recognizing common internal and external areas, configurating to the development environment, coding, simulation proposing and executing of the simulator where a practical case and ten places were evaluated to determine its reliability. The simulator provided the maximum capacity of people who can enter an internal or external area, complying with the social distancing of 2 m. The results made it possible to know that the use of information technologies through programming techniques and the PHP language contributed to being a technological alternative for the fight against the spread of the virus.La confluencia poblacional en áreas internas o externas incrementa considerablemente la trasmisión de la COVID-19, por no respetar el distanciamiento social que establece el sistema de salud. El objetivo de este trabajo fue hacer uso de técnicas de programación, empleando el lenguaje PHP (preprocesador de hipertexto), para el desarrollo de una aplicación que simule el aforo máximo de personas que pueden ingresar a un área interna o externa. La metodología permitió el reconocimiento de áreas internas y externas comunes, configuración al entorno de desarrollo, codificación, propuesta de simulación y ejecución del simulador donde se ha evaluado un caso práctico y diez lugares para determinar su confiabilidad. El simulador brindó el aforo máximo de personas que pueden ingresar a un lugar de área interna o externa cumpliendo el distanciamiento social de 2 m. Los resultados permitieron conocer que el uso de las tecnologías de información a través de las técnicas de programación y el lenguaje PHP contribuyó en ser una alternativa tecnológica para la lucha contra la propagación del virus

    Research of China Insurance Funds Investment Efficiency: Based on the comparison with Social Security Fund

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    2012年以来我国保监会频频出台商业保险资金运用新政,将保险资金运用市场化作为改革突破方向,从创新投资渠道、丰富投资品种、调整投资比例上限等方面促进我国商业保险资金运用效率的提高。商业保险资金的有效利用对提高保险业的盈利能力和偿付能力有着重要的作用,关系到保险业的持续、健康发展,但近年来我国保险资金运用效率偏低的问题已越来越突出,2001-2012年的平均投资收益率仅为4.53%,而在相同的宏观环境和资本市场环境中的全国社会保障基金却取得了不错的业绩报告,2001-2012年的平均投资收益率为8.28%。 基于上述背景,本文试图探究以下三个问题:一是综合衡量风险和收益,社保基金的运作效率是否...China Insurance Regulatory Commission(CIRC)has issued several policies on insurance funds investment to improve the efficiency of insurance funds since 2012,including broaden investment channels, innovate investment tools and gradually relax restrictions on investment proportion, etc. The efficiency of insurance funds affects the profitability and solvency of the insurance industry, thus the inves...学位:经济学硕士院系专业:经济学院_金融学(含保险学)学号:1562010115192

    Plug and Play Modular Façade Construction System for Renovation for Residential Buildings

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    The present paper focuses on the architectural and constructional features required to ensure that building envelope renovation are safe, functional, and adaptable to the building stock, with particular focus on “plug and play” modular facade construction systems. It presents the design of one such system and how it addresses these issues. The outcome of early-stage functional test with a full-scale mock-up system, as well as its applicability to a real construction project is presented. It is found crucial to obtain high quality information about the status of the existing façade with the use of modern technologies such as topographic surveys or 3D scans and point cloud. Detailed design processes are required to ensure the compatibility of manufacture and installation tolerances, along with anchor systems that deliver flexibility for adjustment, and construction processes adapting standard installation methods to the architectural particularities of each case that may hinder its use or require some modification in each situation. This prefabricated plug and play modular system has been tested by reproducing the holistic methodology and new technologies in the market by means of real demonstrators. When compared to more conventional construction methods, this system achieves savings in a real case of 50% (time), 30% (materials) and 25% (waste), thus achieving significant economic savings.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 768718

    Distanciamiento social ante la COVID-19: Simulación del aforo máximo de personas mediante PHP

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    La confluencia poblacional en áreas internas o externas incrementa considerablemente la trasmisión de la COVID-19, por no respetar el distanciamiento social que establece el sistema de salud. El objetivo de este trabajo fue hacer uso de técnicas de programación, empleando el lenguaje PHP (preprocesador de hipertexto), para el desarrollo de una aplicación que simule el aforo máximo de personas que pueden ingresar a un área interna o externa. La metodología permitió el reconocimiento de áreas internas y externas comunes, configuración al entorno de desarrollo, codificación, propuesta de simulación y ejecución del simulador donde se ha evaluado un caso práctico y diez lugares para determinar su confiabilidad. El simulador brindó el aforo máximo de personas que pueden ingresar a un lugar de área interna o externa cumpliendo el distanciamiento social de 2 m. Los resultados permitieron conocer que el uso de las tecnologías de información a través de las técnicas de programación y el lenguaje PHP contribuyó en ser una alternativa tecnológica para la lucha contra la propagación del virus.//Population confluence in internal or external areas considerably increases transmission of COVID-19, due to not respecting the social distancing established by the health system. The objective of this work was to make use of programming techniques, using the PHP language (hypertext preprocessor), for the development of an application that simulates the maximum capacity of people who can enter an internal or external area. The methodology allowed recognizing common internal and external areas, configurating to the development environment, coding, simulation proposing and executing of the simulator where a practical case and ten places were evaluated to determine its reliability. The simulator provided the maximum capacity of people who can enter an internal or external area, complying with the social distancing of 2 m. The results made it possible to know that the use of information technologies through programming techniques and the PHP language contributed to being a technological alternative for the fight against the spread of the virus

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

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    The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe
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