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A 16 Tesla Nbdh block-coil dual dipole is being developed to extend the available field strength for future hadron colliders. The design incorporates several novel features. Current programming ol" 3 independent coil elements is used to control all multipolles over a 20:1 dynamic range of dipole field. Stress management, comprising a lattice of ribs and plates integrated into the coil structure, is used to distribute preload and Lorentz forces so that the stress in the coil never exceeds 100 MPal. Distributed cooling, utilizing spring elements in each coil block, intercepts heat generated by synchrotron radiatimn and beam losses. Rectangular pancake coil geometry accommodates simple fabrication and direct preload in the direction of Lorentz forces. The bore diameter can be optimized for collider requirements (2.5 cm for 50 TeVIbeain vs. 5 cm for 8 TeVheam), so that a 16 Tesla block-coil dipole for 50 TeV/beam requires the same amount of superconductorffrbV as the 8.5 Tesla LHC dipole far 8 TeVheam. A first model of the dipole is currently being built. Figure 1. Cross-section of the block-coil dual dipole. I. INTRODUCTIONIn the endeavor to extend the energy of hadron colliders, the challenge to extend dipole field strength is a natural focus. There has been steady progress in this regard, from 4.5 Tesla at the Tevatron (19801, to 6.5 Tesla at SSC (1993), to 8.5 Tesla at LHC today. The path toward higher field strength has ended, however, for magnets based upon NbTi superconductor: the available transport cumnt decreases rapidly beyond 9 Tesla as critical field is approached. To further extend field (strength, we must turn to A15 superconductors ( m S n and I%&) and high-temperature superconductors (particularly BSCCO 2212). Of these materials, only Nb3Sn is available today as a mature conductor, with long strand length and uniform properties required for dipole fabrication. The design of dipoles utilizing Nb3Sn must address several complications compared to NbTi. First, the Blaments of m S n are fragile, and experience stradn degradation of critical current density j, above a threshold strain U -6~1 0 -~, corresponding to a stress (3 -120 MPa. In a homogeneous coil, this degradation would impose severe limits ilt high field: the Lorentz stress at 16 Tesla is oL = B2 /2 Po = 100 MPa. Typically stress concentration in a

A three-dimensional model is presented for the quantitative prediction of skin injury resulting from certain thermal exposure on the surface. The model is based on the skin damage equation proposed by Henriques and Moritz for the process of protein denaturation. Different from the standard Arrhenius model for protein damage rate, in which the activation energy includes chemical reaction only, strain energy of tissue due to thermal stress is also considered in the current model. Skin thermal response is modeled using the bioheat transfer equation by including water diffusion on the skin surface, and the corresponding thermal stress is predicted using the modified Duhamel-Neuman equation. Strain energy is then obtained by the stress-strain relation. The extent of burn injury is computed from the transient temperature solution and the effect of strain energy on skin damage is investigated. The time-dependent partial differential equations (PDEs) are discretized using Crank-Nicholson finite difference scheme and the resulting sparse linear systems are solved iteratively.

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The Direct Energy Deposition (DED) process utilizes laser energy to melt metal powders and deposit them on the substrate layer to manufacture complex metal parts. This study was applied as a remanufacturing and repair process to fix used parts, which reduced unnecessary waste in the manufacturing industry. However, there could be defects generated during the repair, such as porosity or bumpy morphological defects. Traditionally the operator would use a design of experiment (DOE) or simulation method to understand the printing parameters' influence on the printed part. There are several influential factors: laser power, scanning speed, powder feeding rate, and standoff distance. Each DED machine has a different setup in practice, which results in some uncertainties for the printing results. For example, the nozzle diameter and laser type could be varied in different DED machines. Thus, it was hypothesized that a repair could be more effective if the printing process could be monitored in real-time. In this study, a structured light system (SLS) was used to capture the printing process's layer-wise information. The SLS system is capable of performing 3D surface scanning with a high-resolution of 10 µm. To determine how much material needs to be deposited, given the initial scanning of the part and allowing the realtime observation of each layer's information. Once a defect was found in-situ, the DED machine (hybrid machine) would change the tool and remove the flawed layer. After the repair, the nondestructive approach computed tomography (CT) was applied to examine its interior features. In this research, a DED machine using 316L stainless steel was used to perform the repairing process to demonstrate its effectiveness. The lab-built SLS system was used to capture each layer's information, and CT data was provided for the quality evaluation. The novel manufacturing approach could improve the DED repair quality, reduce the repair time, and promote repair automation. In the future, it has a great potential to be used in the manufacturing industry to repair used parts and avoid the extra cost involved in buying a new part.