22 research outputs found
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
Aerosolized neutral endopeptidase reverses ozone-induced airway hyperreactivity to substance P
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