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Esse trabalho tem por objetivo analisar o conto “Bolinha de ping pong”, de Rimar Segala, demonstrando como essa obra apresenta amalgamações entre linguagem e presença. Para isso iniciaremos uma incursão sobre as artes produzidas por pessoas surdas. A partir disso adentraremos nas amalgamações entre linguagem e presença descritas por Gumbrecht (2010) e, nesse caminho, compreenderemos a presentificação de coisas ausentes e a percepção física, possibilitada através do conto. A partir da análise da presença, podemos concluir que através da obra foi possível identificar diversas amalgamações entre linguagem e presença. Assim, através do conto em questão os expectadores podem sentir em seus corpos aquilo que está distante, podendo essa presentificação nos levar a humanizar a nossa visão sobre as pessoas surdas.

Portable X-ray fluorescence (pXRF) spectrometry offers valuable information for prediction models of soil fertility attributes spatial variation, although this approach is yet scarce in tropical regions. This study aims to predict and build spatial variability maps of soil pH, remaining phosphorus (P-Rem), soil organic matter (SOM) and sum of bases (SB) using pXRF results through stepwise multiple linear regression (SMLR) and Random Forest (RF) in a highly variable tropical area. Composite samples from soil A horizon were collected at 90 points throughout the campus of the Federal University of Lavras, Minas Gerais, Brazil, for pH, P-Rem, SOM, SB and pXRF analyses. RF predictions showed the highest accuracies, especially for P-Rem and SB (R² values of 0.66 and 0.55, respectively). Attributes that showed higher R² in punctual predictions also exhibited higher R² in spatial predictions. Data obtained from pXRF in tandem with RF can be used to assist prediction models for soil fertility attributes, consequently enabling the digital mapping of such attributes and helping to improve the knowledge about the spatial variability of such attributes in soils of tropical climate. This technique can therefore assist in the identification and orientation of adequate management practices in tropical agricultural practices.

In developing countries, the use of proximal and remotely sensed data is of critical importance as a less expensive means of obtaining soils information. While proximal sensor approaches such as portable X-ray fluorescence (pXRF) spectrometry are becoming increasingly used to predict soil properties worldwide, remotely sensed data has also been used for terrain analysis in recent decades with the aid of powerful interpretive algorithms. The aims of this work were to apply a random forest algorithm to model and predict the available contents of Fe, Cu, Mn, and Zn from pXRF data in addition to terrain attributes (TAs) with 5 and 10 m spatial resolution and parent material information. The data were used separately and together in an area with high variability of parent materials. Soil samples (n = 153) were collected, analyzed by pXRF, and subjected to laboratory analyses to determine the available contents of Fe, Cu, Mn, and Zn. Twelve TAs were generated from digital elevation models (DEM). These data were divided into five datasets (or random forest inputs): pXRF data; TA 5 m data; TA 10 m; pXRF + TA 5 m; and pXRF + TA 10 m. Predictions were performed to assess the importance of such variables. Models were validated with an independent set of samples. Finally, the best models were spatially rendered to cover the entire study area and maps were also validated. The combination of pXRF data and TA covariates in addition to parent material information allowed accurate predictions of available Fe, Mn, Cu, and Zn through the random forest algorithm. Parent material information improved the predictions. Pixel size of 10 m resolution promoted better results than 5 m resolution. Available Fe contents were better predicted using only TA data. For the spatial prediction of available micronutrients, validation of maps resulted in R2 of 0.88, RMSE of 59.97 mg kg−1 and ME of 24.00 mg kg−1 for Fe; 0.85, 29.65 mg kg−1, 9.70 mg kg−1 for Mn, 0.64, 3.11 mg kg−1, 0.71 mg kg−1 for Zn and 0.82, 1.17 mg kg−1, 0.43 mg kg−1 for Cu, respectively. Available micronutrient contents can be accurately predicted using pXRF data in association with terrain and parent material information.

During the design of a magnet, people generally pay particular attention to get the largest transverse section with small contribution of undesirable multipoles, and the 2D cross-section is adjusted in that way with a good accuracy. But the poles are often cut with sharp ends in the beam direction. Otherwise, in order to minimize the stray field to avoid interaction with other elements on the beam lines and corner saturation, it is common to define a simple 45/spl deg/ chamber. The such truncated poles will create an amount of multipoles that could exceed the magnet required tolerances. The magnetic length is also affected by the way that the truncation is done. We propose in this paper a handy analytical model that allows both to control integrated focusing forces and magnetic lengths for each type of conventional magnets (dipole, quadrupole, sextupole). The different end pole profiles are simulated with the 3D-program TOSCA for the dipole and the quadrupole cases. To estimate a possible damaging of optical qualities introduced by the end pole profile, we compare the multipole components obtained by a 2D harmonic analysis at the magnet center, with an integrated one along the beam axis, taking into account the entire stray field. The results are then compared with those of the sharp end case.

In all accelerator projects, the low energy part of the accelerator has to be carefully optimized to match the beam characteristic requirements of the higher energy parts. Since 1994 with the beginning of the Injector of Protons for High Intensity (IPHI) project and Source of Light Ions with High Intensities (SILHI) electron cyclotron resonance (ECR) ion source development at CEA/Saclay, we are using a set of two-dimensional (2D) codes for extraction system optimization (AXCEL, OPERA-2D) and beam transport (MULTIPART). The 95 keV SILHI extraction system optimization has largely increased the extracted current, and improved the beam line transmission. From these good results, a 130 mA D+ extraction system for the International Fusion Material Irradiation Facility project has been designed in the same way as SILHI one. We are also now involved in the SPIRAL 2 project for the building of a 40 keV D+ ECR ion source, continuously tunable from 0.1 to 5 mA, for which a special four-electrode extraction system ha...

ACC NIM; International audience; SILHI (High Intensity Light Ion Source) is an ECR ion source producing high intensity proton ordeuteron beams at 95 keV. It is now installed in the IPHI site building, on the CEA/Saclay center. IPHI is a frontend demonstrator of high power accelerator. The source regularly delivers more than 130 mA protons in CWmode and already produced more than 170 mA deuterons in pulsed mode at nominal energy. The last beamcharacterisations, including emittance measurements, space charge compensation analysis and diagnosticimprovements, will be reported. Taking into account the SILHI experience, new developments are in progress tobuild and test a 5 mA deuteron source working in CW mode. This new source will also operate at 2.45 GHz andpermanent magnets will provide the magnetic configuration. This source, of which the design will be discussed,will have to fit in with the SPIRAL 2 accelerator developed at GANIL to produce Radioactive Ion Beams. TheH- test stand status is briefly presented here and detailed in companion papers.This work is partly supported by the European Commission under contract n°: HPRI-CT-2001-50021.

Source of light ions with high intensities The (SILHI) source has been producing proton beams since 1996. The first aim is to produce up to 100 mA cw beams at 95 keV for the injector of protons for high intensity demonstrator. This prototype is developed by a CEA/DSM–CNRS/IN2P3 collaboration for applications such as accelerator driven systems for nuclear waste transmutation, production of radioactive ion beams, or secondary particles. To measure installation reliability, continuous 5 day long runs have been performed. In October 1999, a 99.96% availability was achieved with a single short beam off and a 103 H uninterrupted beam. A new extraction system leads to lower beam losses and higher LEBT transparency. SILHI now produces a 95 keV–130 mA total beam with a proton fraction higher than 80%. Up to a 157 mA (247 mA/cm2) total cw beam has been extracted. The new EPICS control system, electromagnetic interference hardened devices and automatic control procedures now allow us to do longer runs. To analyze th...

Based on the experience of the SILHI electron cyclotron resonance (ECR) ion source for the IPHI accelerator, which produces routinely 100-120 mA H(+) beam, the CEA-Saclay is in charge of the design and realization of the 140 mA cw deuteron source for the IFMIF project (International Fusion Materials Irradiation Facility). IFMIF is an accelerator-based neutron irradiation facility consisting of two accelerators of 125 mA D(+) beam at 40 MeV that hit in parallel a lithium target. IFMIF utilizes the deuteron-lithium (d-Li) neutron, producing a reaction to simulate the 14 MeV neutron environment in deuterium-tritium (D-T) fusion reactors. In the framework of the IFMIF EVEDA phase (Engineering Validation and Engineering Design Activities), we are studying a cw ECR ion source with a new extraction system to allow high current extraction while keeping a low divergence as well as a small emittance. Starting from SILHI five-electrode system with H(+) ions, the extracted beam characteristics as well as electric field conditions are compared with the cases of four- and three-electrode extraction systems. Experimental results made on the SILHI source with H(+) ions are briefly discussed. Extensive experimental results on the new source test bench BETSI are expected as soon as the design and fabrication of a dedicated extraction system with a new set of electrodes will be finished.

A 2.45 GHz electron cyclotron resonance test stand based on a pure volume H− negative ion production is presently running at CEA Saclay. This negative ion source (ECRIN) is working in pulsed mode, up to 10 ms at 10 Hz. Several modifications allowed increasing the extracted H− current from the source. Those results will be summed up in the first part. With the experience collected from this source, a second one using a multi‐cups magnetic structure is under development. Magnetic calculations and simulations showed that an octupolar configuration could allow improving the H− ion production. Those simulations will be discussed and the new set up will also be presented. The source is now being assembled on a new test bench, called BETSI, for light ion source development based on permanent magnet structure.

The high-intensity light ion source (SILHI) is designed to be a prototype source for high power linear accelerators. The goal is to produce a 100 mA proton or a 140 mA deuteron ion beams at 95 keV with rms normalized emittance lower than 0.2 π mm mrad. A 108 mA total beam (J=215 mA/cm2) was extracted in April 1997 (85% H+, 12% H2+, and 3% H3+ fractions) with two electron cyclotron resonance (ECR) zones located at both plasma chamber extremities simultaneously. First beam measurements indicate a 0.17 π mm mrad rms normalized emittance for a 80 mA proton beam at 80 keV. In these conditions, a 96% availability was obtained during an 8 h working day. An intermediate electrode is placed in the accelerator gap to minimize emittance distortions as shown by simulations. Beam analysis were made as a function of the intermediate electrode voltage, the gas flow, the magnetic field, and the 2.45 GHz rf power. First rf plasma coupling observations indicated that the magnetron was too highly coupled with the load (plasma chamber). By adding a second circulator and locking the oscillator with an external signal, this dependence was decreased. Measurements then clearly show that the output spectrum is completely independent of the load phasing. All these results will be presented.

The frequency ranges of electrical accelerating fields for heavy ion synchrotrons are often very wide. Their dynamics are limited by the physical characteristics of the magnetic load in the resonant structures. We built an accelerating system, with only one gap, using amorphous material, able to replace the two actual MIMAS cavities (the Saturne II booster), in order to make free a part of the ring. The frequency range can be swept at 4 kV. The RF voltage can be increased up to 10 kV, and the frequency to 12 MHz. The geometrical size was chosen to minimize the operation troubles during the cavities permutation on the machine. >

In the framework of several International HPPA projects (such as IFMIF, IPHI, and Spiral2) the CEA handles the design and the developments of several electron cyclotron resonance (ECR) ion sources. For the IFMIF EVEDA demonstrator, a 140 mA cw extracted deuteron beam will be required for high yield of neutron production. For radioactive ion production in the Spiral2 project, several milliamperes of deuterons will be delivered with a permanent magnet source. The optimization of the beam quality at the entrance of the radio frequency quadropole (RFQ) accelerator system triggered the need of a new test bench for ion source optimization and beam qualification. The BETSI ion source test bench will operate up to 50 kV and ignite cw or pulsed hydrogen plasma with a 2.45 GHz magnetron. Great care has already been taken to design electrostatic optics of the extraction system to minimize the emittance growth. Plasma diagnostics will be inserted in the source chamber and several beam diagnostics (emittance and current measurements, beam species analysis) will also be implemented on the low energy beam line transport (LEBT). These diagnostics allow the simultaneous analysis of the beam quality with the plasma parameters of the source. Regional funding request will also be needed to improve the LEBT for space charge compensation measurements. The design of the present and upgraded test bench will be reported as well as the first extracted beam analysis.

In the framework of the IFMIF-EVEDA phase (International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities), the CEA-Saclay is in charged of the design and realization of the 140 mA cw deuteron source. The IFMIF EVEDA demonstrator will be installed in Japan in the next six years and will have to accelerate the deuteron beam up to 9 MeV. CEA will build the source and the low energy beam line (LEBT) and will test the cw high intensity deuteron production at Saclay. The SILHI source is an electron cyclotron resonance (ECR) source, operating at 2.45 GHz. In 2001, it produced more than 130 mA of deuteron beam in pulsed mode to minimize neutron production. Such a result pushes to develop a new ECR source based on the SILHI design and equipped with a specific extraction system. Several options of the accelerator column will be implemented in order to improve the reliability and the efficiency of the source. The IFMIF source and LEBT design will be reported.

International audience; In France, the Spiral 2 project dedicated to radioactive beam production is based on a 40 MeV continuous wave (cw) deuteron Linac. This installation will allow extending the variety of accelerated particles to very heavy elements. Such beams will open research domains for the GANIL facility. To inject the requested 5 mA deuteron beam into the Spiral 2 Linac, the performance of the high intensity light ion source (SILHI) allowed us to propose such an electron cyclotron resonance source. SILHI, developed at CEA/Saclay, regularly produces high intensity (over 100 mA) proton or deuteron beams through a $\Phi$ 9 mm aperture. So for this project, the main modifications of the source design concern the permanent magnets which provide the axial magnetic configuration and the $\Phi$ 3 mm aperture. The source produced its first beam (proton) in 2004. This article will report the beam characterization while the source produced $D^+$ beam with intensity as high as 7.0 mA. Recently, this permanent magnet source has been equipped with the $\Phi$ 9 mm plasma electrode. So high intensity proton beams reaching more than 100 mA are now extracted from this source.

The high intensity light ion source (SILHI) is the electron cyclotron resonance (ECR) source constructed and tested at CEA-Saclay. The first aim is to produce up to 100 mA cw proton beams at 95 keV for the proton injection high intensity (IPHI) beams [5 MeV radio frequency quadrupole (RFQ) and 10 MeV drift tube linac (DTL)]. This prototype is developed by a CEA–CNRS-IN2P3 collaboration for applications such as accelerator driven systems for nuclear waste transmutation, production of radioactive ion beams or secondary particles. SILHI is also used to study the production of deuteron and H− beams for the International Fusion Material Irradiation Facility and European spallation source projects, respectively. The present status of SILHI and the experiments planned for the near future in both cw and pulsed modes are presented in this article. 80 mA cw proton beams are now currently produced at 95 keV with a high availability (∼1 spark/day). The proton fraction is around 90% and the typical r–r′ rms normalized...