ITER LHe Plants Parallel Operation

AbstractThe ITER Cryogenic System includes three identical liquid helium (LHe) plants, with a total average cooling capacity equivalent to 75kW at 4.5K.The LHe plants provide the 4.5 K cooling power to the magnets and cryopumps. They are designed to operate in parallel and to handle heavy load variations.In this proceedingwe will describe the presentstatusof the ITER LHe plants with emphasis on i) the project schedule, ii) the plantscharacteristics/layout and iii) the basic principles and control strategies for a stable operation of the three LHe plants in parallel

Process for production of allyl alcohol

The invention relates to a process for producing allyl alcohol, the process comprising: dehydrating a C3-oxygenate domprising monopropylene gycol or 1,3-propanediol; wherein the dehydration is performed in the presence of a basic catalyst. The C3-oxygenate may be dreived from a biomass conversion process and subsequently converted to acrylic acid

Suppression of host innate immune response by Burkholderia pseudomallei through the virulence factor TssM

10.4049/jimmunol.0902663Journal of Immunology18495160-5171JOIM

Nonlinear control of a membrane mirror strip actuated axially and in bending

The sliding mode technique is used to control the deformation of a membrane mirror strip augmented with two macrofiber composite bimorphs located near the ends of the strip. The first bimorph is actuated in bending and the second is actuated axially. The structure is modeled as an Euler–Bernoulli beam under tensile load and the macrofiber composite patches are modeled as monolithic piezoceramic wafers. To cast the system into a finitedimensional state-space form, the finite element method is used, and the model presented accounts for the dynamics of the augmented bimorphs. The membrane strip is placed under uniform tension. Because one of the bimorphs acts axially, the resulting tension in the membrane strip is discontinuous at the location of this bimorph and, consequently, the obtained model is nonlinear. First, we validate the model experimentally by considering the system in its quasilinear state, then we consider the control problem. We formulate the regulation problem by using the sliding mode technique. Additionally, to allow coupling this system with an adaptive optics scheme, the shape-control problem is considered as well. The control law uses both actuators: the bending and axial bimorphs. However, a system singularity dictates using a switching command to avoid this singularity. Various examples are presented for the regulation and shape-control problems. The simulation results demonstrate the efficacy of the proposed control law