Search

Algunos de los ejercicios profesionales ligados a la salud mental incluyen la supervisión y lasupervisión a supervisores. Dichas responsabilidades predisponen al profesional a una exposición deun elevado nivel de estrés así como desgaste y posible trauma vicario. Estos efectos pueden repercutiren la calidad de servicio brindado al supervisando, con el riesgo de tener un efecto nocivo en el cliente.Con la fnalidad de explorar los posibles benefcios de las actividades experienciales en la expresiónemocional en personas que sufren estrés, se diseñó y se llevó a cabo un taller piloto experiencial con lamodalidad de artes expresivas como propuesta para autocuidado de los profesionales de la salud mental.Los resultados obtenidos en este taller sugieren un diseño de intervención que pueda ser utilizado para elautocuidado de supervisores y otros profesionales de la salud mental.

This paper analyses the current distribution in no-insulation (NI) coils in a layer-wound configuration. The investigation aims at comparing the electrical characteristic of two coils wound from the same BSCCO tape, with or without electrical insulation between turns. Both coils are characterized by a very similar geometry, with the same number of turns and layers. Both coils, cooled in liquid nitrogen bath, are charged until the tape critical current is exceeded. To interpret the measurements and analyze the current distribution within the winding, a lumped-parameter equivalent electrical circuit is developed and solved numerically in a time-varying regime. The model results are compared with the signals acquired through voltage taps soldered at the same locations in both coils. Finally, the model is applied to investigate the impact of the transverse contact resistance and to estimate the most stressed locations of the coil during charging, in terms of power produced by Joule effect.

The measurement of transport current ac losses in high-temperature superconductor tapes with the electric method has been extensively discussed in the literature. It is well known that the configuration of the circuit used to acquire the voltage signal can affect the measured losses, potentially leading to inaccurate results. To reduce this undesired effect, the rectangular circuit arrangement, which is widely adopted, involves twisting the pair of voltage taps at a given distance from the tape middle axis. However, the explanations reported in the literature to identify the correct distance are not fully exhaustive, and an alternative interpretation is described here. Moreover, given that the conventional voltage taps arrangement creates a significant circuit area to which electromagnetic noise can be linked, an alternative configuration is proposed, aiming to reduce the linked flux. This article presents a theoretical analysis to quantify the impact of the measurement circuit configuration on the losses. To ensure clarity, the model equations involved are derived step by step. The numerical results are applied to a thorough investigation on the accuracy of the ac losses measured on a sample tape, at different frequencies and current amplitudes. Both the conventional and the alternative arrangements are studied, varying their main geometrical parameters, at the same operating conditions. The correction terms are then applied to the measurement results, highlighting the advantages and drawbacks of the different configurations.

The technological revolution, particularly the availability of more data and more powerful computational tools, has led to the emergence of a new scientific field called “Computational Diplomacy”. Our work tries to define its scope and focuses on a popular subarea of it, namely “Digital Democracy”. In recent years, there has been a surge of interest in using digital technologies to promote more participatory forms of democracy. While there are numerous potential benefits to using digital tools to enhance democracy, significant challenges must be addressed. It is essential to ensure that digital technologies are used in an accessible, equitable, and fair manner rather than reinforcing existing power imbalances. This paper investigates how digital tools can be used to help design more democratic societies by investigating three key research areas: (1) the role of digital technologies for facilitating civic engagement in collective decision-making; (2) the use of digital tools to improve transparency and accountability in governance; and (3) the potential for digital technologies to enable the formation of more inclusive and representative democracies. We argue that more research on how digital technologies can be used to support democracy upgrade is needed. Along these lines, we lay out a research agenda for the future., Journal of Computational Science, 71, ISSN:1877-7503

In the family of the High-Luminosity LHC high order correctors, the skew quadrupole was the most critical magnet as three assemblies with different solutions were needed to meet the design specifications. This paper summarizes the prototyping phase of the magnet, discussing the observed nonconformities, the subsequent root cause analyses, and the adopted solutions. A first-hand experience showed us the importance of adopting rigorous quality assurance methods for the electrical insulation, aimed at the early defect detection, and implementing a consistent measurement-to-simulations chain for the optimization of the coils mechanical support. The improvements discussed in the paper are integrated into the final magnet design for the series production of six skew quadrupole correctors.

This article presents a numerical model based on the definition of the scalar and vector potentials to calculate the ac losses generated in a high-temperature superconductor coated conductor tape by an ac transport current and by an ac external magnetic field applied with a generic orientation. The material characteristics of the different layers of a reference tape are included in the model equations, which allow analyzing the differences between a model including only the superconducting layer or all layers of the coated conductor. The model is applied to study the dependence of ac losses on the amplitude of the transport current and magnetic field (applied individually or combined) and their frequency. The numerical results are compared with analytical formulations, with a second numerical model based on the H -formulation, and with experimental results. The conditions at which the contribution of the nonsuperconducting layers to the total ac losses of the tape become relevant are analyzed. In particular, the dependence of losses on the frequency of the ac external magnetic field applied at different orientations, is investigated. The current density distribution computed on the conductor cross-section is used to explain the trend of the calculated losses.

INFN is developing at LASA laboratory (Milano, Italy) the prototypes of five high order corrector magnets, from skew quadrupole to dodecapole, which will equip the high-luminosity interaction regions of the High Luminosity-LHC (HL-LHC). These magnets are based on a superferric design, which allows a relatively simple, modular and easy to construct magnet. This activity takes place within the framework of a collaboration agreement between CERN and INFN. Four prototypes, from sextupole to dodecapole, have been built and tested starting in 2016. We present here the last prototype of the high order correctors, to be installed in LHC, the skew quadrupole: magnetic and mechanical design are discussed together with quench protection. We report also on the overall experience gained during construction aiming toward the series production. The power test of the quadrupole, including the training, the qualification and the quench behavior in operational conditions are also described.

High Energy Research Organization (KEK) has developed three short-scale model magnets of the beam separation dipole, MBXF, which is to be installed for the High Luminosity Large Hadron Collider, HL-LHC, in CERN. We will soon undertake production of a prototype of MBXF and its magnetic design has to be finalized before the fabrication. We established a strategy for designing the new coil cross section by taking into account different error sources for its field quality. In this paper, focused on b 3 , we describe how the final b 3 integral, which should be within 2.9 units according to the acceptance criteria, is achievable.

Nb-Ti based large-aperture beam separation dipoles (MBXFs) will be installed on both sides of two interaction points, ATLAS and CMS, for the high-luminosity LHC upgrade. The most important requirements for MBXF is a coil aperture of 150 mm and the field integral of 35 T⋅m. Nominal dipole field is 5.6 T at 12 kA and 1.9 K. KEK is in charge of developing MBXF within a framework of CERN-KEK collaboration. This study reports training performance of three 2-m long model magnets (MBXFS1–3) assembled under different mechanical support conditions. Azimuthal pre-stress both in the straight section and at coil end, and axial pre-load were controlled to counteract Lorentz force. In MBXFS2 and 3, wet-winding was also applied but solely to the coil end. Quench start locations for the model magnets are compared to validate the effectiveness of each support method.

In collaboration with CERN, High Energy Accelerator Research Organization (KEK) has designed and developed short-scale model magnets of the beam separation dipole, MBXF, which will be installed for the High Luminosity Large Hadron Collider, HL-LHC. A new quench protection heater for MBXF was designed and tested during the cold test of the short-scale models. Combining data taken since the test of the 1st model magnet, we confirmed the maximum hotspot temperatures are well below 300 K in the case of the low field (1 T) and high field (5 T) quenches, respectively. In addition, a simulation model was developed and tuned with the obtained data for the full-scale prototype magnet. The hotspot temperature after quench initiation was then computed with the new heater circuit and found to be below 300 K even for the case of failure in firing the heater.

The High Luminosity LHC (HL-LHC) is a program to upgrade the performance of the collider in order to achieve, in the ATLAS and CMS collision regions, instantaneous luminosities a factor of five larger than the actual nominal value. To obtain this result, all the magnets in the collision region will have to be substituted, together with other important devices. In the framework of this program, the Italian National Institute for Nuclear Physics (INFN-LASA laboratory) is entrusted to develop five corrector magnets (skew quadrupole, sextupole, octupole, decapole, and dodecapole), which in the magnet chain will have to correct the magnetic imperfections of the main magnets in the regions (low-beta quadrupoles Q1/Q3 and dipole D1/D2). These corrector magnets have been designed with relatively simple, robust, and easy to construct concepts, using superferric configuration. The first prototypes, a sextupole, an octupole, and a decapole, have been tested in 2016 and 2017. We present here the prototype of dodecapole. We report magnetic and mechanical designs and the experience during construction. The qualification, the cold test, and the quench behavior in operational conditions are also described.

Large aperture beam separation dipoles (D1 magnet) must be developed for the interaction regions in the high-luminosity large hadron collider (HL-LHC). The most important specifications of this magnet are a coil aperture of 150 mm and field integral of 35 Tm, which will be realized by Nb-Ti superconducting magnets operated at 12 kA at 1.9 K. High Energy Accelerator Research Organization (KEK) is developing 2-m-long model magnets for D1. The first model magnet was re-assembled after increasing the coil pre-stress (MBXFS1b); subsequently, it showed good training performance, achieving maximum quench current, which was higher than the ultimate current. However, mechanical support of the coils was still insufficient in MBXFS1b. Especially at coil end, some coil end blocks deformed toward the coil bore due to Lorentz force. In the second model magnet (MBXFS2), the change of iron yoke cross section was requested so that the position of heat exchanger holes penetrating iron yoke is in agreement with those of the final focusing Nb 3 Sn quadrupole magnets. Because this has a large impact on field quality, magnetic design including the magnet's cross section and coil end shape was updated. Some countermeasures were also taken to enhance mechanical support of the coil such as wet-winding with radiation-resistant resin at coil end and increase in coil pre-stress. This paper reports design update, fabrication, and training performance of MBXFS2 with new iron cross section.

We report the test results of the second short model magnet of the beam separation dipole for the High Luminosity Large Hadron Collider. The test shows that the second model has a good training performance and is capable of operating at the ultimate current that corresponds to 108% of the nominal one. Magnetic field measurements reveal that b 3 is around 18 units, which is 15 units higher than the calculations. This can be explained in part by geometrical coil deformation caused during the construction process.

Rutherford cables for particle accelerator magnets are subjected to time dependent magnetic fields during the typical accelerator operating cycle, which in turn induce coupling currents flowing in the loops formed at the contacts between different strands. An analysis of the magnitude and losses associated with these coupling currents is relevant to the design of field quality and cryogenic heat loads. The models reported in the literature exhibit some limits related to computational burden when applied to the analysis of interstrand coupling currents for real cable geometries, and conceptual limits when trying to couple different physical simulations. To solve this problem, a continuum model of Rutherford cables was improved to account for the non-uniform contact conductances between the strands along the cable length, also developing a novel strategy for the computation of the induced voltages. Thanks to these features we attain the required level of detail in the description of the short-range interstrand currents, which could not be properly computed with earlier versions of the continuum model. The model was validated by comparison with analytical results available in the literature for simplified case studies with uniform magnetic field applied orthogonal to the cable. Examples of current and loss distributions are presented in the paper, to prove the potential of the model to analyze Rutherford cables of any configuration. A study regarding the proper choice of the boundary conditions of the problem is presented, which suggests the need for experimental investigation on the actual distribution of currents and losses in the long cable lengths used in accelerator magnets.

This paper presents a numerical method, based on the partial element equivalent circuit (PEEC) technique, for spatially-distributed and time-varying simulation to analyze nonlinear 'defect-irrelevant' behaviors of a no-insulation (NI) high temperature superconductor (HTS) coil. We suggest a resistivity parameterization approach in combination of the PEEC method to replicate electromagnetic dynamics of an NI HTS coil containing multiple 'defects.' The proposed method is adopted to investigate 'defect-irrelevant' behaviors of an NI single pancake coil having lap joints as a form of artificial defects. To validate our approach, electromagnetic characteristics of the NI test coil are measured in a bath of liquid nitrogen at 77 K and compared with four key simulation results: (a) local voltages; (b) current distribution; (c) magnetic field; and (d) Joule heating distribution. Experimental measurements of local voltages and the magnetic field are compared to the simulation results to validate our numerical method.

INFN is developing at the LASA lab (Milano, Italy) the High Order (HO) corrector magnets for the High Luminosity-LHC (HL-LHC) project, which will equip the interaction regions. Five prototypes, from skew quadrupole to dodecapole, have been designed and tested at LASA. All the HO correctors are based on a superferric design, which allows a relatively simple, modular, and easy to construct magnet. This modularity has been exploited for an engineering change request. The tradeoff between safe handling, force management during cooldown, powering and protection of the magnet is explained in detail. The design of the coils and the mechanical assembly have been improved to increase the efficiency of the series production. Most of the optimizations are aimed to guarantee both a good integration in the LHC framework (i.e., radiation hardness, easiness of installation, safe operation over years), and compatibility with the series production (i.e., standardization of procedures and components for different magnets, reduction of the number of components, standardization of the quality control systems and acceptance tests). All of the produced magnets will be tested at LASA and then delivered to CERN. The design of the test-bed and the optimization of cryogenic and testing procedures is also described in this paper. Following the completion of the prototyping phase, we report in detail the solutions chosen for the HO correctors and we give a perspective of the series construction in industry and acceptance tests at LASA.

This work extends to second generation Rare-Earth Barium-Copper-Oxide ((Re)BCO) tapes an experimental procedure previously developed to analyze the impact of double bending at room temperature on the performance of Bismuth-Strontium-Calcium-Copper-Oxide (BSCCO) tapes. The modified procedure is applied to measure the critical current of a commercial (Re)BCO tape subjected to bending around a cylindrical mandrel first on one side, then on the other side, followed by the cooldown to cryogenic temperature. In the bending phase, mandrels of decreasing diameter are used to identify the minimum curvature leading to a significant reduction of the tape critical current. Furthermore, a novel finite element model is developed to complement the experimental results. The model simulates the double bending at room temperature, the following straightening of the sample, and its cooldown to cryogenic conditions. The coupled thermo-mechanical numerical model together with the temperature-dependent mechanical properties allow investigating the combination of thermal contraction effects and bending loads in the whole domain of the problem. The experimental and numerical results obtained help to give a better insight in the distribution of the strain and stress components inside the (Re)BCO tape and to evaluate their impact on the conductor electrical performance in relevant operating conditions.

The National Institute for Nuclear Physics (INFN) is developing at the Laboratory of Accelerators and Applied Superconductivity (LASA) laboratory (Milano, Italy) the prototypes of five corrector magnets, from skew quadrupole to dodecapole, which will equip the high-luminosity interaction regions of the High Luminosity Large Hadron Collider (HL-LHC). These magnets are based on a superferric design, which allows a relatively simple, compact, and easy to construct magnet. This activity takes place within the framework of a collaboration agreement between European Organization for Nuclear Research (CERN) and INFN. The first prototypes, a sextupole and an octupole, have been tested in 2016 and 2017, respectively. We present here the results of the cold tests of the decapole that has been assembled and tested in the second half of 2017, including the training performed at 4.2 K and the qualification at 2.17 K. We report also on the overall experience gained during construction and tests and the improvements toward the series production. Other important results concern quench studies.

Rutherford cables for particle accelerator magnets can be subjected to a time-varying magnetic field during the typical accelerator operating cycle, which in turn induces coupling currents flowing in the loops formed at the contacts between different strands. A proper analysis of the losses generated by these currents must be carried out for the design of the cryogenic system. A continuum model with nonuniform contact conductances between the strands was recently developed, starting from a previous continuum model based on uniform conductances between strands along the cable length. The model allows one to attain the required level of detail in the description of the interstrand currents. This model is applied here to analyze the effect of the insertion of a resistive core between the two layers of the cable, and to assess quantitatively the impact of the main core parameters, such as its width, positioning, and electrical resistance.

INFN is developing at LASA Laboratory (Milano, Italy) the prototypes of five corrector magnets, from skew quadrupole to dodecapole, which will equip the high-luminosity interaction regions (IRs) of the High Luminosity-LHC (HL-LHC). These magnets are based on a superferric design, to allow a relatively simple, modular, and easy to construct magnet. This program takes place within the framework of a collaboration agreement between CERN and INFN. In this paper, we present an overview of the activity, from the design, to the construction and test at the operation condition.

A large aperture beam separation dipole (D1 magnet) is required to generate a field integral of 35 Tm at 12 kA and 1.9 K for the high luminosity upgrade of the large hadron collider (HL-LHC). High-energy accelerator Research Organization (KEK) fabricated the first 2 m model (MBXFS1) and a magnet test was performed in 2015–2016. Although the quench current reached the nominal operating current, training performance was not satisfactory. The measured azimuthal coil pre-stress was completely released below the nominal current, and this was suggested to be the main reason for the insufficient training performance. After the magnet test, MBXFS1 was disassembled and reassembled as MBXFS1b after increasing the coil pre-stress. In this paper, we report the reassembly of the magnet and test results focusing on the training performance.

The beam separation dipole magnet (D1), which is being operated in the large hadron collider (LHC), has to be replaced in accordance with upgrade to the high-luminosity LHC. The new D1 will be equipped with several circuits of heaters by which most of the stored energy is dissipated in the whole of the magnet during its quench, thereby avoiding localization of hot spots. Prior to construction of the production magnet, the 2-m mechanical short model is fabricated, and performance of this quench protection heater is evaluated through a series of the cold tests. As a result, we confirm that the maximum hot spot temperature obtained in the measurement reaches the practical limit of 300 K, and determine to design a new heater circuit. In this paper, we report the heater studies together with the prospect for future design of the quench protection heater.

A beam separation dipole magnet for the high luminosity large hadron collider upgrade is developed. The development of the 2-m-long model magnet (MBXFS1) was initiated so as to evaluate the design and performance of the beam separation dipole magnet. In the first cold test in 2016, the quench performance was not satisfactory because the coil prestress at the pole was completely released during excitation. After reassembly to improve the quench performance, the excitation test of the modified model magnet (MBXFS1b) was performed at 1.9 K in 2017 at KEK. Due to the large coil aperture and limited outer diameter of the iron yoke, the control of iron saturation effects on the field quality has been a design issue. Regarding the magnetic performance, field saturation effects on the transfer function and the multipole field variation along the excitation, and coil end effects to the straight section need to be evaluated by the field measurement. In this paper, field measurement results will be presented and the comparison with the three-dimensional field calculation will be discussed.

The large aperture superconducting beam separation dipole (D1) must be developed as part of the high luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN. The most important specifications of the D1 are a coil aperture of 150 mm and field integral of 35 T·m at 12.0 kA and 1.9 K. The technical challenges of this magnet include predicting the changes in the size of the coils during fabrication, achieving a high radiation resistance, and management of the iron saturation. KEK is in charge of developing the D1. After conducting a series of design studies, a design consisting of a single-layer coil based on Nb-Ti technology with a collared yoke structure was selected. The fabrication of the first 2 m model of the D1 started at KEK in 2015. Newly developed radiation resistant glass-fiber-reinforced-plastics were utilized as coil parts in the accelerator magnets for the first time. The 2 m model was subjected to two cycles of cold test in the vertical cryostat at KEK. In this paper, we report on the fabrication of the 2 m model. We also present and discuss the quench test results from the perspective of the coil prestress.

INFN is developing at LASA lab (INFN Milano, Italy) the prototypes of five corrector magnets, from skew quadrupole to dodecapole, which will equip the high-luminosity interaction regions of the High Luminosity-LHC. These magnets are based on a superferric design, which allows a relatively simple, modular, and easy to construct magnet. This activity takes place within the framework of a collaboration agreement between CERN and INFN. The first prototype, a sextupole, has been assembled in early 2016. We present here the results of the cold test, including the training performed at 4.2 K and the qualification at 2.2 K. We report also on the overall experience gained during its construction and test. An important aspect is represented by the analysis of the manufacturing tolerances of the mechanical pieces and the alignment accuracy achieved. These results will serve as a basis for the design of the next magnets, the octupole, and the decapole. Other important results concern the cold performance of the coil-to-coil electrical joints (especially critical in a magnet with a large number of coils), dynamic inductance measurements and quench studies.

KEK has been developing a beam separation dipole magnet for the high luminosity large hadron collider upgrade. The magnet has a coil aperture of 150 mm and uses NbTi superconducting cable. A dipole magnetic field of 5.6 T is generated at 12 kA at 1.9 K to provide a field integral of 35 T·m. KEK has started the development of the first 2-m-long model magnet to evaluate the design and performance of the beam separation dipole magnet. The excitation test at 1.9 K of the first 2-m-long model magnet was performed from April to June 2016 at KEK. This paper presents the results of the magnetic field measurements of the first 2-m-long model magnet by a rotating coil probe.

The High Energy Accelerator Research Organization (KEK) has been developing the beam separation dipole magnet for the High Luminosity Large Hadron Collider (HL-LHC) upgrade. The magnet has a coil aperture of 150 mm, using Nb-Ti superconducting cable, and a dipole magnetic field of 5.6 T will be generated at 12 kA, at 1.9 K, to provide the field integral of 35 T·m. To verify the mechanical behavior of the magnet and to optimize the fabrication processes, we develop a 200-mm short model, which is the cross-sectional cutout of the magnet. The development includes validation of a series of fabrication processes. Coil stress in pole was monitored by strain gauges during collaring, yoking, and cooldown test.

The first Large Hadron Collider (LHC) Long Shutdown (LS1) started in February 2013. It was triggered by the need to consolidate the 13-kA splices between the superconducting magnets to allow the LHC to reach safely its design energy of 14 TeV center of mass. The Superconducting Magnets and Circuits Consolidation (SMACC) project has principally covered the consolidation of the 10170 13-kA splices but also other activities linked to the superconducting magnets such as the exchange of 18 main cryomagnets, the installation of the additional safety relief devices, the repair of known helium leaks, and other consolidation activities. All these works have been structured in a project, gathering about 280 persons. The opening of the interconnections started in April 2013 and consolidation works were completed by September 2014. This paper first describes the preparation phase with the building of the teams and the detailed planning of the operations. Then, this paper carried out is summarized, and the main results achieved are presented. Finally, it gives feedback from the worksite, namely lessons learnt and adaptations that were implemented, both from the technical and organizational points of view.

The National Institute for Nuclear Physics (INFN) is developing, within the framework of a collaboration agreement with the European Organization for Nuclear Research (CERN), prototypes of five corrector magnets, from skew quadrupoles to dodecapoles, which will equip the high-luminosity interaction regions of the high-luminosity Large Hadron Collider. These magnets are based on a superferric design, which allows a relatively simple, modular, and easy-to-construct magnet. In this paper, we review the main features of the corrector magnets, and we present the results of the manufacture of the sextupole superconducting coils, from the development of suitable solutions for the winding and impregnation to the quality assessment on the series coils, including the results of the first cryogenic tests on a single coil.

The measurement of AC losses in high temperature superconducting tapes is a complex task due to the small magnitude of the quantities to detect, and to the difficulty to separate the inductive and resistive parts of the measured voltage. This work describes a different approach to the electrical measurement of AC losses, not requiring lock-in amplifiers for the signal processing. The system is based on the acquisition of the voltage and current signals from the sample and their projection on a reference signal, performing a Hilbert transform based treatment procedure. This method allows one to retrieve the harmonic components of the signals with a significant noise reduction, thus improving the quality of the results. The experimental set-up is applied to measure AC losses in different HTS tapes, using sinusoidal currents of different amplitude and frequency. The results are compared with those obtained on the same tapes at other laboratories.

The about 1700 interconnections (ICs) between the Large Hadron Collider (LHC) superconducting magnets include thermal shielding at 50-75 K, providing continuity to the thermal shielding of the magnet cryostats to reduce the overall radiation heat loads to the 1.9 K helium bath of the magnets. The IC shield, made of aluminum, is conduction-cooled via a welded bridge to the thermal shield of the adjacent magnets which is actively cooled. TIG welding of these bridges made in the LHC tunnel at installation of the magnets induced a considerable risk of fire hazard due to the proximity of the multi-layer insulation of the magnet shields. A fire incident occurred in one of the machine sectors during machine installation, but fortunately with limited consequences thanks to prompt intervention of the operators. LHC is now undergoing a 2 years technical stop during which all magnet's ICs will have to be opened to consolidate the magnet electrical connections. The IC thermal shields will therefore have to be removed...

The high-luminosity Large Hadron Collider (HL-LHC) upgrade project aims to increase the LHC peak luminosity up to 5×10 34 cm -2 s -1 and the integrated luminosity up to3000 fb -1 . To achieve this goal, the quadrupole and dipole magnets around the two interaction points, i.e., the ATLAS and the CMS, will be upgraded. The High Energy Accelerator Research Organization (KEK) is in charge of the development of beam separation dipole (D1). In new D1, the coil aperture is enlarged to be 150 mm, and an integrated field of 35 T · m is required at 1.9 K and 12.0 kA. This paper reports the current status of the development of a 2-m model magnet.

The final interconnections of the LHC superconducting magnets in the underground tunnel are performed by a contractor on a result-oriented basis. A consortium of firms was awarded the contract after competitive tendering based on a technical and commercial specification. The implementation of the specific technologies and tooling developed and qualified by CERN has required an important effort to transfer the know-how and implement the follow-up of the contractor. This paper summarizes the start-up phase and the difficulties encountered. The organization and management tools put in place during the ramping-up phase are presented. In addition to contractual adaptations of the workforce, several configuration changes to the workflows were necessary to reach production rates compatible with the overall schedule and with the different constraints: availability of magnets, co-activities with magnets transport and alignment, handling of non-conformities, etc. Also the QA procedures underwent many changes to reach the high level of quality mandatory to ensure the LHC performance. The specificities of this worksite are underlined and first figures of merit of the learning process are presented.

The first LHC long shutdown (LS1) started in February 2013. It was triggered by the need to consolidate the 13 kA splices between the superconducting magnets to allow the LHC to reach safely its design energy of 14 TeV center of mass. The final design of the consolidated splices is recalled. 1695 interconnections containing 10 170 splices have to be opened. In addition to the work on the 13 kA splices, the other interventions performed during the first long shut-down on all the superconducting circuits are described. All this work has been structured in a project, gathering about 280 persons. The opening of the interconnections started in April 2013 and consolidation works are planned to be completed by August 2014. This paper describes first the preparation phase with the building of the teams and the detailed planning of the operation. Then, it gives feedback from the worksite, namely lessons learnt and adaptations that were implemented, both from the technical and organizational points of view. Finally, perspectives for the completion of this consolidation campaign are given.

El estudio del origen de la Psicología permite trazar sus bases como ciencia. Así, los experimentos de Wundt, en el primer laboratorio en Leipzig, las raíces que vinculan a la psicología con teorías del aprendizaje y con el condicionamiento, y las recientes conclusiones derivadas de la neuropsicología, dan fe de tal perfil.

The performance of High Temperature Superconducting (HTS) tapes is strongly affected by the mechanical loadings they experience during manufacturing, cooldown and operation. Therefore, the development of HTS-based applications requires thorough investigations on the impact of these loadings on the critical current. In this work, a measurement procedure is applied to determine the critical current of a (Re)BCO tape at 77 K, after double bending at room temperature around a cylindrical mandrel. In this procedure, the tape is cooled down to cryogenic temperature, and the critical current is first measured on the straight sample. After warming the tape up to room temperature, a double bending around a cylindrical mandrel is applied in two opposite directions and the critical current is measured at the following cooldown. This analysis is repeated for different mandrel diameters in order to identify to study the impact of the curvature radius on the performance degradation. The application of one single bending at room temperature is compared to the results of the double bending procedure. The influence on the performance degradation of applying a known force to the tape during the double bending at room temperature is also experimentally analyzed.