Header logo is


2002


no image
Morphology and thermal stability of metal contacts on crystalline organic thin films

Dürr, A. C., Schreiber, F., Kelsch, M., Carstanjen, H. D., Dosch, H.

{Advanced Materials}, 14(13-14):961-963, 2002 (article)

mms

[BibTex]

2002


[BibTex]


no image
Magnetic Imaging of Nanostructured Systems with Transmission X-Ray Microscopy

Eimüller, T.

Bayrische Julius-Maximilians-Universität Würzburg, Würzburg, 2002 (phdthesis)

mms

[BibTex]

[BibTex]


no image
Magnetic anisotropy of textured CrO2 thin films investigated by X-ray magnetic circular dichroism

Goering, E., Justen, M., Geissler, J., Rüdiger, U., Rabe, M., Güntherodt, G., Schütz, G.

{Applied Physics A-Materials Science \& Processing}, 74(6):747-753, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Identification of nanocrystal nucleation and growth in Al85Ni5Y8CO2 metallic glass with quenched-in nuclei

Wang, J. Q., Zhang, H. W., Gu, X. J., Lu, K., Sommer, F., Mittemeijer, E. J.

{Applied Physics Letters}, 80(18):3319-3321, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Ab-initio Berechnung der Spinwellenspektren von Eisen, Kobalt und Nickel

Grotheer, O.

Universität Stuttgart, Stuttgart, 2002 (phdthesis)

mms

[BibTex]

[BibTex]


no image
Master equations for the concentrations of atomic defects in B2 compounds

Meyer, B., Fähnle, M.

{Physica Status Solidi B-Basic Research}, 229(3):1139-1143, 2002 (article)

mms

[BibTex]

[BibTex]


no image
On the electronic structure of the pure and oxygen covered Ru(0001) surface

Bester, G., Fähnle, M.

{Surface Science}, 497(1-3):305-310, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Atomic defects and diffusion in intermetallic compounds: The impact of the ab initio electron theory

Fähnle, M.

{Diffusion and Defect Forum}, 203-205, pages: 37-46, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Switching behavior of single nanowires inside dense nickel nanowire arrays

Nielsch, K., Hertel, R., Wehrspohn, R. B., Barthel, J., Kirschner, J., Gösele, U., Fischer, S. F., Kronmüller, H.

{IEEE Transactions on Magnetics}, 38(5):2571-2573, 2002 (article)

mms

[BibTex]

[BibTex]


no image
On the magnetoelastic contribution to the magnetic anisotropy of thin epitaxial Permalloy films: an ab initio study

Komelj, M., Fähnle, M.

{Journal of Magnetism and Magnetic Materials}, 238(2-3):L125-L128, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Nanostructured graphite-hydrogen systems prepared by mechanical milling method

Orimo, S. I., Matsushima, T., Fujii, H., Fukunaga, T., Majer, G., Zuttel, A., Schlapbach, L.

{Molecular Crystals and Liquid Crystals}, 386, pages: 173-178, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Micromagnetic analysis of pinning-hardened nanostructured, nanocrystalline Sm2Co17 based alloys

Kronmüller, H., Goll, D.

{Scripta Materialia}, 47, pages: 545-550, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Study of magnetic domains by magnetic soft x-ray transmission microscopy

Fischer, P., Denbeaux, G., Ono, T., Okuno, T., Eimüller, T., Goll, D., Schütz, G.

{Journal of Physics D-Applied Physics}, 35(19):2391-2397, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Ion beam-induced sintering of near-surface layers

Föhl, A., Carstanjen, H. D.

{Surface \& Coatings Technology}, 158, pages: 69-74, 2002 (article)

mms

[BibTex]

[BibTex]


no image
High density hexagonal nickel nanowire array

Nielsch, K., Wehrspohn, R. B., Barthel, J., Kirschner, J., Fischer, S. F., Kronmüller, H., Schweinbock, T., Weiss, D., Gösele, U.

{Journal of Magnetism and Magnetic Materials}, 249(1-2):234-240, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Kernspinresonanzuntersuchungen zur Diffusion von Wasserstoff in kubischen Lavesphasen

Eberle, U.

Universität Stuttgart, Stuttgart, 2002 (phdthesis)

mms

[BibTex]

[BibTex]


no image
Strong anisotropy of projected 3d moments in epitaxial CrO2 films

Goering, E., Bayer, A., Gold, S., Schütz, G., Rabe, M., Rüdiger, U., Güntherodt, G.

{Physical Review Letters}, 88(20), 2002 (article)

mms

[BibTex]

[BibTex]


no image
Density-functional study of Fe3Al: LSDA versus GGA

Lechermann, F., Welsch, F., Elsässer, C., Ederer, C., Fähnle, M., Sanchez, J. M., Meyer, B.

{Physical Review B}, 65(13), 2002 (article)

mms

[BibTex]

[BibTex]


no image
Critical magnetic properties of disordered polycrystalline Cr75Fe25 and Cr70Fe30 alloys

Fischer, S. F., Kaul, S. N., Kronmüller, H.

{Physical Review B}, 65(6), 2002 (article)

mms

[BibTex]

[BibTex]


no image
Magnetic properties of ion-beam sputtered Cr3Fe-alloy films

Fischer, S. F., Kaul, S. N., Kronmüller, H.

{Journal of Magnetism and Magnetic Materials}, 240(1-3):374-376, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Model-independent measurements of hydrogen diffusivity in the yttrium dihydrides

Majer, G., Gottwald, J., Peterson, D. T., Barnes, R. G.

{Journal of Alloys and Compounds}, 330-332, pages: 438-442, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Strong anisotropy of projected Cr3d moments of epitaxial grown CrO2-films

Goering, E., Bayer, A., Gold, S., Schütz, G.

{Bessy-Highlights}, pages: 26-27, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Change from a bulk discontinuous phase transition in V2H to a contiuous transition in a defective near-surface skin layer

Trenkler, J., Abe, H., Wochner, P., Haeffner, D., Bail, J., Carstanjen, H. D., Moss, S.

{Modelling and Simulation in Materials Science and Engineering}, 8, pages: 269-275, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Hydrogen Storage in Nanostructured Carbon Materials at Room Temperature

Chen, X., Dettlaff-Weglikowska, U., Haluska, M., Hirscher, M., Becher, M., Roth, S.

In Structural and Electronic Properties of Molecular Nanostructures, pages: 597-600, AIP Conference Proceedings, AIP, Kirchberg, Tirol [Austria], 2002 (inproceedings)

mms

[BibTex]

[BibTex]


no image
Ion Channeling in Quasicrystals

Plachke, D., Carstanjen, H. D.

In Quasicrystals. An Introduction to Structure, Physical Properties and Applications, 55, pages: 280-304, Springer Series in Materials Science, Springer, Berlin [et al.], 2002 (incollection)

mms

[BibTex]

[BibTex]


no image
Movement imitation with nonlinear dynamical systems in humanoid robots

Ijspeert, J. A., Nakanishi, J., Schaal, S.

In International Conference on Robotics and Automation (ICRA2002), Washinton, May 11-15 2002, 2002, clmc (inproceedings)

Abstract
Locally weighted learning (LWL) is a class of statistical learning techniques that provides useful representations and training algorithms for learning about complex phenomena during autonomous adaptive control of robotic systems. This paper introduces several LWL algorithms that have been tested successfully in real-time learning of complex robot tasks. We discuss two major classes of LWL, memory-based LWL and purely incremental LWL that does not need to remember any data explicitly. In contrast to the traditional beliefs that LWL methods cannot work well in high-dimensional spaces, we provide new algorithms that have been tested in up to 50 dimensional learning problems. The applicability of our LWL algorithms is demonstrated in various robot learning examples, including the learning of devil-sticking, pole-balancing of a humanoid robot arm, and inverse-dynamics learning for a seven degree-of-freedom robot.

am

link (url) [BibTex]

link (url) [BibTex]


no image
A locally weighted learning composite adaptive controller with structure adaptation

Nakanishi, J., Farrell, J. A., Schaal, S.

In IEEE International Conference on Intelligent Robots and Systems (IROS 2002), Lausanne, Sept.30-Oct.4 2002, 2002, clmc (inproceedings)

Abstract
This paper introduces a provably stable adaptive learning controller which employs nonlinear function approximation with automatic growth of the learning network according to the nonlinearities and the working domain of the control system. The unknown function in the dynamical system is approximated by piecewise linear models using a nonparametric regression technique. Local models are allocated as necessary and their parameters are optimized on-line. Inspired by composite adaptive control methods, the pro-posed learning adaptive control algorithm uses both the tracking error and the estimation error to up-date the parameters. We provide Lyapunov analyses that demonstrate the stability properties of the learning controller. Numerical simulations illustrate rapid convergence of the tracking error and the automatic structure adaptation capability of the function approximator. This paper introduces a provably stable adaptive learning controller which employs nonlinear function approximation with automatic growth of the learning network according to the nonlinearities and the working domain of the control system. The unknown function in the dynamical system is approximated by piecewise linear models using a nonparametric regression technique. Local models are allocated as necessary and their parameters are optimized on-line. Inspired by composite adaptive control methods, the pro-posed learning adaptive control algorithm uses both the tracking error and the estimation error to up-date the parameters. We provide Lyapunov analyses that demonstrate the stability properties of the learning controller. Numerical simulations illustrate rapid convergence of the tracking error and the automatic structure adaptation capability of the function approximator

am

link (url) [BibTex]

link (url) [BibTex]


no image
Vacancies in thermal equilibrium and ferromagnetism near the Curie temperature

Seeger, A., Fähnle, M.

{Zeitschrift f\"ur Metallkunde}, 93(10):1030-1042, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Magnetic imaging with soft X-ray microscopy

Fischer, P., Denbeaux, G., Eimüller, T., Goll, D., Schütz, G.

{IEEE Transactions on Magnetics}, 38(5):2427-2431, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Theory of induced magnetic moments and x-ray magnetic circular dichroism in Co-Pt multilayers

Ederer, C., Komelj, M., Fähnle, M., Schütz, G.

{Physical Review B}, 66(9), 2002 (article)

mms

[BibTex]

[BibTex]


no image
Determination of the complete set of second-order magnetoelastic coupling constants on epitaxial films

Komelj, M., Fähnle, M.

{Physical Review B}, 65(21), 2002 (article)

mms

[BibTex]

[BibTex]


no image
Undulation instabilities in laterally structured magnetic multilayers

Eimüller, T., Scholz, M., Guttmann, P., Köhler, M., Bayreuther, G., Schmahl, G., Fischer, P., Schütz, G.

{Journal of Applied Physics}, 91(10):7334-7336, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Initial oxidation of AlPdMn quasicrystals - A study by high-resolution RBS and ERDA

Plachke, D., Khellaf, A., Carstanjen, H. D.

{Nuclear Instruments \& Methods in Physics Research B}, 190, pages: 646-651, 2002 (article)

mms

[BibTex]

[BibTex]


no image
The Verwey transition - a topical review

Walz, F.

{Journal of Physics-Condensed Matter}, 14(12):R285-R340, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Composition dependence of the Zener relaxation in high-purity FeCr single crystals

Hirscher, M., Ege, M.

{Materials \textquotesingleTransactions JIM}, 43(2):182-185, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Hydrogen storage in carbon nanostructures

Hirscher, M., Becher, M., Haluska, M., Quintel, A., Skakalova, V., Choi, Y. M., Dettlaff-Weglikowska, U., Roth, S., Stepanek, I., Bernier, P., Leonhardt, A., Fink, J.

{Journal of Alloys and Compounds}, 330, pages: 654-658, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Micromagnetism and the microstructure of the cell walls in Sm2Co17 based permanent magnets

Goll, D., Hadjipanayis, G. C., Kronmüller, H.

In Proceedings of the 17th International Workshop on Rare-Earth Magnets and their Applications, pages: 696-703, Rinton Press, Newark, Delaware, USA, 2002 (inproceedings)

mms

[BibTex]

[BibTex]


no image
Micromagnetic investigation of sub-100-nm magnetic domains in atomically stacked Fe(001)/Au(001) multilayers

Köhler, M., Zweck, J., Bayreuther, G., Fischer, P., Schütz, G., Denbeaux, G., Attwood, D.

{Journal of Magnetism and Magnetic Materials}, 240, pages: 79-82, 2002 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Experimental Study of a Crystal Positron Source

Chehab, R., Cizeron, R., Sylvia, C., Baier, V., Beloborodov, K., Bukin, A., Burdin, S., Dimova, T., Drozdetsky, A., Druzhinin, V., Dubrovin, M., Golubev, V., Serednyakov, S., Shary, V., Strakhovenko, V., Artru, X., Chevallier, M., Dauvergne, D., Kirsch, R., Lautesse, P., Poizat, J. C., Remillieux, J., Jejcic, A., Keppler, P., Major, J., Gatignon, L., Bochek, G., Kulibaba, V., Maslov, N., Bogdanov, A., Potylitsin, A., Vnukov, I.

{Physics Letters B}, 525, pages: 41-48, 2002 (article)

mms

[BibTex]

[BibTex]


no image
Ab-initio study of the influence of epitaxial strain on magnetoelastic properties

Komelj, M., Fähnle, M.

In Atomistic Aspects of Epitaxial Growth, pages: 439-447, NATO Science series: Series 2, Mathematics, Physics, and Chemistry, Kluwer Academic Publishers, Dassia, Corfu [Greece], 2002 (inproceedings)

mms

[BibTex]

[BibTex]

1995


no image
A kendama learning robot based on a dynamic optimization theory

Miyamoto, H., Gandolfo, F., Gomi, H., Schaal, S., Koike, Y., Osu, R., Nakano, E., Kawato, M.

In Preceedings of the 4th IEEE International Workshop on Robot and Human Communication (RO-MAN’95), pages: 327-332, Tokyo, July 1995, clmc (inproceedings)

am

[BibTex]

1995


[BibTex]


no image
Batting a ball: Dynamics of a rhythmic skill

Sternad, D., Schaal, S., Atkeson, C. G.

In Studies in Perception and Action, pages: 119-122, (Editors: Bardy, B.;Bostma, R.;Guiard, Y.), Erlbaum, Hillsdayle, NJ, 1995, clmc (inbook)

am

[BibTex]

[BibTex]


no image
Memory-based neural networks for robot learning

Atkeson, C. G., Schaal, S.

Neurocomputing, 9, pages: 1-27, 1995, clmc (article)

Abstract
This paper explores a memory-based approach to robot learning, using memory-based neural networks to learn models of the task to be performed. Steinbuch and Taylor presented neural network designs to explicitly store training data and do nearest neighbor lookup in the early 1960s. In this paper their nearest neighbor network is augmented with a local model network, which fits a local model to a set of nearest neighbors. This network design is equivalent to a statistical approach known as locally weighted regression, in which a local model is formed to answer each query, using a weighted regression in which nearby points (similar experiences) are weighted more than distant points (less relevant experiences). We illustrate this approach by describing how it has been used to enable a robot to learn a difficult juggling task. Keywords: memory-based, robot learning, locally weighted regression, nearest neighbor, local models.

am

link (url) [BibTex]

link (url) [BibTex]

1994


no image
Robot juggling: An implementation of memory-based learning

Schaal, S., Atkeson, C. G.

Control Systems Magazine, 14(1):57-71, 1994, clmc (article)

Abstract
This paper explores issues involved in implementing robot learning for a challenging dynamic task, using a case study from robot juggling. We use a memory-based local modeling approach (locally weighted regression) to represent a learned model of the task to be performed. Statistical tests are given to examine the uncertainty of a model, to optimize its prediction quality, and to deal with noisy and corrupted data. We develop an exploration algorithm that explicitly deals with prediction accuracy requirements during exploration. Using all these ingredients in combination with methods from optimal control, our robot achieves fast real-time learning of the task within 40 to 100 trials.

am

link (url) [BibTex]

1994


link (url) [BibTex]


no image
Robot learning by nonparametric regression

Schaal, S., Atkeson, C. G.

In Proceedings of the International Conference on Intelligent Robots and Systems (IROS’94), pages: 478-485, Munich Germany, 1994, clmc (inproceedings)

Abstract
We present an approach to robot learning grounded on a nonparametric regression technique, locally weighted regression. The model of the task to be performed is represented by infinitely many local linear models, i.e., the (hyper-) tangent planes at every query point. Such a model, however, is only generated when a query is performed and is not retained. This is in contrast to other methods using a finite set of linear models to accomplish a piecewise linear model. Architectural parameters of our approach, such as distance metrics, are also a function of the current query point instead of being global. Statistical tests are presented for when a local model is good enough such that it can be reliably used to build a local controller. These statistical measures also direct the exploration of the robot. We explicitly deal with the case where prediction accuracy requirements exist during exploration: By gradually shifting a center of exploration and controlling the speed of the shift with local prediction accuracy, a goal-directed exploration of state space takes place along the fringes of the current data support until the task goal is achieved. We illustrate this approach by describing how it has been used to enable a robot to learn a challenging juggling task: Within 40 to 100 trials the robot accomplished the task goal starting out with no initial experiences.

am

[BibTex]

[BibTex]