Ferramentas para a caracterização de painéis fotovoltaicos

Neste trabajo apresentamos procedimientos y herramientas para la caracterización completa de paneles fotovoltaicos. Como punto de partida, fueron obtenidas las curvas caracteristicas provenidas por el fabricante. En un segundo momento fueron hechas coletas manuales de dados para la confección de las curvas caracteristicas. A partir de las propriedades fisicas de semiconductores el modelamento del panel fue establecido. El procedimiento establecido és muy fatigoso y reiterativo, podendo llevar a imprecisiones. Para la automatización deste procedimiento, lo siguiente sistema fue proyectado y montado: un conversor dc/dc permite realizar el control electronico de carga resistiva; un computadora realiza el control cíclico de la variación de carga del panel. Un sistema de aquisición de dados permite la obtención de los parámetros en el panel. A partir desta coleta de dados automatizada un software constroe las curvas caracteristicas.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

CERN’s bulk niobium high gradient SRF programme: developments and recent cold test results

Recent results from the bulk niobium high-gradient cavity development program at CERN are presented, with particular focus on test results for the 704 MHz bulk niobium 5-cell elliptical cavity prototypes produced for the Superconducting Proton Linac (SPL) project. Successive cold tests of bare cavities have been used to refine the cavity preparation and testing process, with all steps done in-house at CERN. Current performance results are discussed with reference to observables such as ambient magnetic field, field emission levels, and quenches

Plans for an ERL Test Facility at CERN

The baseline electron accelerator for LHeC and one option for FCC-he is an Energy Recovery Linac. To prepare and study the necessary key technologies, CERN has started – in collaboration with JLAB and Mainz University – the conceptual design of an ERL Test Facility (ERL-TF). Staged construction will allow the study under different conditions with up to 3 passes, beam energies of up to about 1 GeV and currents of up to 50 mA. The design and development of superconducting cavity modules, including coupler and HOM damper designs, are also of central importance for other existing and future accelerators and their tests are at the heart of the current ERL-TF goals. The ERL-TF could also provide a unique infrastructure for several applications that go beyond developing and testing the ERL technology at CERN. In addition to experimental studies of beam dynamics, operational and reliability issues in an ERL, it could equally serve for quench tests of superconducting magnets, as physics experimental facility on its own right or as test stand for detector developments. This contribution will describe the goals and the concept of the facility and the status of the R&D;

Diagnostic developments at CERN’s SRF testing facility

As part of CERN’s re-establishment of an SRF cold testing facility for bulk niobium cavities, diagnostic instrumentation and testing procedures on our vertical cryostat have been upgraded, with particular attention given to quench location, ambient magnetic field control, thermometry and thermal cycling techniques. In addition, preparation and measurement procedures have been addressed, allowing for improved measurement of cavity properties and detailed study of transient effects during the course of cavity testing

International thought in the Lula era Pensamento internacional na era Lula

In the last fifty years, Brazil began a rapid process of structural transformation, following the first stage of industrial development in the 1930s. Currently the country integrates the small group of countries which evolved from an initial peripheral and subordinate insertion dating back to the nineteenth century, part of the most dynamic segment of the semiperiphery. But this category, intermediate between the "maturity" and "backwardness", according Modernization theorists, or between the "center" and "periphery", as theorists of the Dependence defend, has undergone a process of overcoming considerable positive progress in the direction of the group of states that dominate the current world system. In this way, during the years 2003-2010, foreign policy, along with the formulation of a new regionalism as a strategy of global integration and a new ideal model of State, has been a key factor<br>Nos últimos 50 anos, o Brasil passou por um processo de rápidas transformações estruturais, seguidas do primeiro estágio de desenvolvimento industrial nos anos 30. Atualmente, o Brasil integra um pequeno número de países que saiu da condição de periferia e subordinação do século XIX para um grupo mais dinâmico de semi-periferia. Porém, essa é uma categoria intermediária entre maturidade e atraso, de acordo com teóricos da modernização; ou uma categoria entre centro e periferia, segundo teóricos da Dependência. Esse é um estágio do processo de superação de progressivas considerações positivas na direção de um grupo de Estados que dominam o sistema mundial atual. Nesse sentido, durante os anos 2003- 2010, a política externa tem se tornado um fator fundamental, junto com sua formulação de um novo regionalismo como estratégia de integração global e um novo modelo de Estad

The Large Hadron–Electron Collider at the HL-LHC

The Large Hadron–Electron Collider (LHeC) is designed to move the field of deep inelastic scattering (DIS) to the energy and intensity frontier of particle physics. Exploiting energy-recovery technology, it collides a novel, intense electron beam with a proton or ion beam from the High-Luminosity Large Hadron Collider (HL-LHC). The accelerator and interaction region are designed for concurrent electron–proton and proton–proton operations. This report represents an update to the LHeC's conceptual design report (CDR), published in 2012. It comprises new results on the parton structure of the proton and heavier nuclei, QCD dynamics, and electroweak and top-quark physics. It is shown how the LHeC will open a new chapter of nuclear particle physics by extending the accessible kinematic range of lepton–nucleus scattering by several orders of magnitude. Due to its enhanced luminosity and large energy and the cleanliness of the final hadronic states, the LHeC has a strong Higgs physics programme and its own discovery potential for new physics. Building on the 2012 CDR, this report contains a detailed updated design for the energy-recovery electron linac (ERL), including a new lattice, magnet and superconducting radio-frequency technology, and further components. Challenges of energy recovery are described, and the lower-energy, high-current, three-turn ERL facility, PERLE at Orsay, is presented, which uses the LHeC characteristics serving as a development facility for the design and operation of the LHeC. An updated detector design is presented corresponding to the acceptance, resolution, and calibration goals that arise from the Higgs and parton-density-function physics programmes. This paper also presents novel results for the Future Circular Collider in electron–hadron (FCC-eh) mode, which utilises the same ERL technology to further extend the reach of DIS to even higher centre-of-mass energies

Importance of Baseline Prognostic Factors With Increasing Time Since Initiation of Highly Active Antiretroviral Therapy: Collaborative Analysis of Cohorts of HIV-1-Infected Patients

Background: The extent to which the prognosis for AIDS and death of patients initiating highly active antiretroviral therapy (HAART) continues to be affected by their characteristics at the time of initiation (baseline) is unclear. Methods: We analyzed data on 20,379 treatment-naive HIV-1- infected adults who started HAART in 1 of 12 cohort studies in Europe and North America (61,798 person-years of follow-up, 1844 AIDS events, and 1005 deaths). Results: Although baseline CD4 cell count became less prognostic with time, individuals with a baseline CD4 count 350 cells/μL (hazard ratio for AIDS = 2.3, 95% confidence interval [CI]: 1.0 to 2.3; mortality hazard ratio = 2.5, 95% CI: 1.2 to 5.5, 4 to 6 years after starting HAART). Rates of AIDS were persistently higher in individuals who had experienced an AIDS event before starting HAART. Individuals with presumed transmission by means of injection drug use experienced substantially higher rates of AIDS and death than other individuals throughout follow-up (AIDS hazard ratio = 1.6, 95% CI: 0.8 to 3.0; mortality hazard ratio = 3.5, 95% CI: 2.2 to 5.5, 4 to 6 years after starting HAART). Conclusions: Compared with other patient groups, injection drug users and patients with advanced immunodeficiency at baseline experience substantially increased rates of AIDS and death up to 6 years after starting HAART