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We report new petrological data and geochronological measurements of granulites from Vesleknausen in the highest-grade section of the Lutzow-Holm Complex, part of the Gondwana-assembling collisional orogen in East Antarctica. The locality is dominated by felsic to intermediate orthogneiss (charnockite and minor biotite gneiss), mafic orthogneiss, and hornblende-pyroxene granulite, with deformed and undeformed dykes of metagranite and felsic pegmatite. Pseudosection analysis of charnockite in the system NCKFMASHTO, supported by geothermometry of mafic orthogneiss, was used to infer peak metamorphic temperatures of 750–850 °C, approximately 150 °C lower than those estimated for metasedimentary gneisses from Rundvagshetta, 6 km to the northeast. SHRIMP U-Pb analysis of zircons from feldspar-pyroxene gneiss, which corresponds to a partially molten patch around mafic orthogneiss, yielded a Concordia upper intercept ages of 2507.9 ± 7.4 Ma, corresponding to the time of formation of the magmatic protolith to the orthogneiss. Partial melting during peak metamorphism probably took place between 591 and 548 Ma, as recorded in rims overgrew around magmatic zircon. Our results suggest that Rundvagshetta-Vesleknausen-Strandnibba region in southwestern Lutzow-Holm Bay, where orthogneisses are dominant, consists of a single crustal block, possibly formed by ca. 2.5 Ga arc magmatism. The Neoarchean magmatic terrane was tectonically mingled with other fragments (such as metasedimentary units in northern Lutzow-Holm Bay) by subduction/collision events during the assembly of Gondwana supercontinent, and subsequently underwent ∼850 °C granulite-facies metamorphosed during Neoproterozoic to Cambrian final collisional event.

We discuss a design of controller for a two-link flexible arm based on a distributed parameter model. Using Lyapunov method, we derive a PDS controller that the system becomes Lyapunov stable and that the system in neighborhood of a desired configuration becomes asymptotically stable. As the controller is derived based on the distributed parameter model, we can avoid the drawbacks resulting from finite dimensional approximation.

We discuss a force control problem for a constrained one-link flexible arm based on distributed parameter model. In order to solve the force control problem, we propose a simple feedback control law. This control law consists of bending moment at the root of the flexible arm and its derivative, which regulates simultaneously the force and the rotational angle of the motor without the angle and the force information. Then it provides the exponential stability of the closed-loop system by using energy multiplier method. As the control law is derived based on the distributed parameter model, we can avoid the drawbacks resulting from finite dimensional approximation.