Header logo is


2002


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]

2002


[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
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
A micromechanical flying insect thorax

Fearing, R., Avadhanula, S., Campolo, D., Sitti, M., Yan, J., Wood, R.

Neurotechnology for Biomimetic Robots, pages: 469-480, The MIT Press Cambridge, MA, 2002 (article)

pi

[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
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
Evidence for van der Waals adhesion in gecko setae

Autumn, K., Sitti, M., Liang, Y. A., Peattie, A. M., Hansen, W. R., Sponberg, S., Kenny, T. W., Fearing, R., Israelachvili, J. N., Full, R. J.

Proceedings of the National Academy of Sciences, 99(19):12252-12256, National Acad Sciences, 2002 (article)

pi

Project Page [BibTex]

Project Page [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
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]

1999


no image
Lernen mit Kernen: Support-Vektor-Methoden zur Analyse hochdimensionaler Daten

Schölkopf, B., Müller, K., Smola, A.

Informatik - Forschung und Entwicklung, 14(3):154-163, September 1999 (article)

Abstract
We describe recent developments and results of statistical learning theory. In the framework of learning from examples, two factors control generalization ability: explaining the training data by a learning machine of a suitable complexity. We describe kernel algorithms in feature spaces as elegant and efficient methods of realizing such machines. Examples thereof are Support Vector Machines (SVM) and Kernel PCA (Principal Component Analysis). More important than any individual example of a kernel algorithm, however, is the insight that any algorithm that can be cast in terms of dot products can be generalized to a nonlinear setting using kernels. Finally, we illustrate the significance of kernel algorithms by briefly describing industrial and academic applications, including ones where we obtained benchmark record results.

ei

PDF PDF DOI [BibTex]

1999


PDF PDF DOI [BibTex]


no image
Input space versus feature space in kernel-based methods

Schölkopf, B., Mika, S., Burges, C., Knirsch, P., Müller, K., Rätsch, G., Smola, A.

IEEE Transactions On Neural Networks, 10(5):1000-1017, September 1999 (article)

Abstract
This paper collects some ideas targeted at advancing our understanding of the feature spaces associated with support vector (SV) kernel functions. We first discuss the geometry of feature space. In particular, we review what is known about the shape of the image of input space under the feature space map, and how this influences the capacity of SV methods. Following this, we describe how the metric governing the intrinsic geometry of the mapped surface can be computed in terms of the kernel, using the example of the class of inhomogeneous polynomial kernels, which are often used in SV pattern recognition. We then discuss the connection between feature space and input space by dealing with the question of how one can, given some vector in feature space, find a preimage (exact or approximate) in input space. We describe algorithms to tackle this issue, and show their utility in two applications of kernel methods. First, we use it to reduce the computational complexity of SV decision functions; second, we combine it with the kernel PCA algorithm, thereby constructing a nonlinear statistical denoising technique which is shown to perform well on real-world data.

ei

Web DOI [BibTex]

Web DOI [BibTex]


no image
p73 and p63 are homotetramers capable of weak heterotypic interactions with each other but not with p53.

Davison, T., Vagner, C., Kaghad, M., Ayed, A., Caput, D., CH, ..

Journal of Biological Chemistry, 274(26):18709-18714, June 1999 (article)

Abstract
Mutations in the p53 tumor suppressor gene are the most frequent genetic alterations found in human cancers. Recent identification of two human homologues of p53 has raised the prospect of functional interactions between family members via a conserved oligomerization domain. Here we report in vitro and in vivo analysis of homo- and hetero-oligomerization of p53 and its homologues, p63 and p73. The oligomerization domains of p63 and p73 can independently fold into stable homotetramers, as previously observed for p53. However, the oligomerization domain of p53 does not associate with that of either p73 or p63, even when p53 is in 15-fold excess. On the other hand, the oligomerization domains of p63 and p73 are able to weakly associate with one another in vitro. In vivo co-transfection assays of the ability of p53 and its homologues to activate reporter genes showed that a DNA-binding mutant of p53 was not able to act in a dominant negative manner over wild-type p73 or p63 but that a p73 mutant could inhibit the activity of wild-type p63. These data suggest that mutant p53 in cancer cells will not interact with endogenous or exogenous p63 or p73 via their respective oligomerization domains. It also establishes that the multiple isoforms of p63 as well as those of p73 are capable of interacting via their common oligomerization domain.

ei

Web [BibTex]

Web [BibTex]


no image
Estimating the support of a high-dimensional distribution

Schölkopf, B., Platt, J., Shawe-Taylor, J., Smola, A., Williamson, R.

(MSR-TR-99-87), Microsoft Research, 1999 (techreport)

ei

Web [BibTex]

Web [BibTex]


no image
Spatial Learning and Localization in Animals: A Computational Model and Its Implications for Mobile Robots

Balakrishnan, K., Bousquet, O., Honavar, V.

Adaptive Behavior, 7(2):173-216, 1999 (article)

ei

[BibTex]

[BibTex]


no image
SVMs for Histogram Based Image Classification

Chapelle, O., Haffner, P., Vapnik, V.

IEEE Transactions on Neural Networks, (9), 1999 (article)

Abstract
Traditional classification approaches generalize poorly on image classification tasks, because of the high dimensionality of the feature space. This paper shows that Support Vector Machines (SVM) can generalize well on difficult image classification problems where the only features are high dimensional histograms. Heavy-tailed RBF kernels of the form $K(mathbf{x},mathbf{y})=e^{-rhosum_i |x_i^a-y_i^a|^{b}}$ with $aleq 1$ and $b leq 2$ are evaluated on the classification of images extracted from the Corel Stock Photo Collection and shown to far outperform traditional polynomial or Gaussian RBF kernels. Moreover, we observed that a simple remapping of the input $x_i rightarrow x_i^a$ improves the performance of linear SVMs to such an extend that it makes them, for this problem, a valid alternative to RBF kernels.

ei

GZIP [BibTex]

GZIP [BibTex]


no image
Generalization Bounds via Eigenvalues of the Gram matrix

Schölkopf, B., Shawe-Taylor, J., Smola, A., Williamson, R.

(99-035), NeuroCOLT, 1999 (techreport)

ei

[BibTex]

[BibTex]


no image
Sparse kernel feature analysis

Smola, A., Mangasarian, O., Schölkopf, B.

(99-04), Data Mining Institute, 1999, 24th Annual Conference of Gesellschaft f{\"u}r Klassifikation, University of Passau (techreport)

ei

PostScript [BibTex]

PostScript [BibTex]


Parameterized modeling and recognition of activities
Parameterized modeling and recognition of activities

Yacoob, Y., Black, M. J.

Computer Vision and Image Understanding, 73(2):232-247, 1999 (article)

Abstract
In this paper we consider a class of human activities—atomic activities—which can be represented as a set of measurements over a finite temporal window (e.g., the motion of human body parts during a walking cycle) and which has a relatively small space of variations in performance. A new approach for modeling and recognition of atomic activities that employs principal component analysis and analytical global transformations is proposed. The modeling of sets of exemplar instances of activities that are similar in duration and involve similar body part motions is achieved by parameterizing their representation using principal component analysis. The recognition of variants of modeled activities is achieved by searching the space of admissible parameterized transformations that these activities can undergo. This formulation iteratively refines the recognition of the class to which the observed activity belongs and the transformation parameters that relate it to the model in its class. We provide several experiments on recognition of articulated and deformable human motions from image motion parameters.

ps

pdf pdf from publisher DOI [BibTex]

pdf pdf from publisher DOI [BibTex]


no image
< 研究速報>(< 小特集> マイクロマシン)

Sitti, M., 橋本秀紀,

生産研究, 51(8):651-653, 東京大学, 1999 (article)

pi

[BibTex]

[BibTex]


no image
Micro/Nano Manipulation Using Atomic Force Microscope.

Sitti, M., Hashimoto, H.

生産研究, 51(8):651-653, 東京大学生産技術研究所, 1999 (article)

pi

[BibTex]

[BibTex]


no image
Is imitation learning the route to humanoid robots?

Schaal, S.

Trends in Cognitive Sciences, 3(6):233-242, 1999, clmc (article)

Abstract
This review will focus on two recent developments in artificial intelligence and neural computation: learning from imitation and the development of humanoid robots. It will be postulated that the study of imitation learning offers a promising route to gain new insights into mechanisms of perceptual motor control that could ultimately lead to the creation of autonomous humanoid robots. This hope is justified because imitation learning channels research efforts towards three important issues: efficient motor learning, the connection between action and perception, and modular motor control in form of movement primitives. In order to make these points, first, a brief review of imitation learning will be given from the view of psychology and neuroscience. In these fields, representations and functional connections between action and perception have been explored that contribute to the understanding of motor acts of other beings. The recent discovery that some areas in the primate brain are active during both movement perception and execution provided a first idea of the possible neural basis of imitation. Secondly, computational approaches to imitation learning will be described, initially from the perspective of traditional AI and robotics, and then with a focus on neural network models and statistical learning research. Parallels and differences between biological and computational approaches to imitation will be highlighted. The review will end with an overview of current projects that actually employ imitation learning for humanoid robots.

am

link (url) [BibTex]

link (url) [BibTex]


no image
Virtual Reality-Based Teleoperation in the Micro/Nano World.

Sitti, M., Hashimoto, H.

生産研究, 51(8):654-656, 東京大学生産技術研究所, 1999 (article)

pi

[BibTex]

[BibTex]


no image
Segmentation of endpoint trajectories does not imply segmented control

Sternad, D., Schaal, D.

Experimental Brain Research, 124(1):118-136, 1999, clmc (article)

Abstract
While it is generally assumed that complex movements consist of a sequence of simpler units, the quest to define these units of action, or movement primitives, still remains an open question. In this context, two hypotheses of movement segmentation of endpoint trajectories in 3D human drawing movements are re-examined: (1) the stroke-based segmentation hypothesis based on the results that the proportionality coefficient of the 2/3 power law changes discontinuously with each new â??strokeâ?, and (2) the segmentation hypothesis inferred from the observation of piecewise planar endpoint trajectories of 3D drawing movements. In two experiments human subjects performed a set of elliptical and figure-8 patterns of different sizes and orientations using their whole arm in 3D. The kinematic characteristics of the endpoint trajectories and the seven joint angles of the arm were analyzed. While the endpoint trajectories produced similar segmentation features as reported in the literature, analyses of the joint angles show no obvious segmentation but rather continuous oscillatory patterns. By approximating the joint angle data of human subjects with sinusoidal trajectories, and by implementing this model on a 7-degree-of-freedom anthropomorphic robot arm, it is shown that such a continuous movement strategy can produce exactly the same features as observed by the above segmentation hypotheses. The origin of this apparent segmentation of endpoint trajectories is traced back to the nonlinear transformations of the forward kinematics of human arms. The presented results demonstrate that principles of discrete movement generation may not be reconciled with those of rhythmic movement as easily as has been previously suggested, while the generalization of nonlinear pattern generators to arm movements can offer an interesting alternative to approach the question of units of action.

am

link (url) [BibTex]

link (url) [BibTex]


no image
Teleoperated nano scale object manipulation

Sitti, M., Hashimoto, H.

Recent Advances on Mechatronics, pages: 322-335, Singapore: Springer-Verlag, 1999 (article)

pi

[BibTex]

[BibTex]

1994


no image
View-based cognitive mapping and path planning

Schölkopf, B., Mallot, H.

(7), Max Planck Institute for Biological Cybernetics Tübingen, November 1994, This technical report has also been published elsewhere (techreport)

Abstract
We present a scheme for learning a cognitive map of a maze from a sequence of views and movement decisions. The scheme is based on an intermediate representation called the view graph. We show that this representation carries sufficient information to reconstruct the topological and directional structure of the maze. Moreover, we present a neural network that learns the view graph during a random exploration of the maze. We use a unsupervised competitive learning rule which translates temporal sequence (rather than similarity) of views into connectedness in the network. The network uses its knowledge of the topological and directional structure of the maze to generate expectations about which views are likely to be perceived next, improving the view recognition performance. We provide an additional mechanism which uses the map to find paths between arbitrary points of the previously explored environment. The results are compared to findings of behavioural neuroscience.

ei

[BibTex]

1994


[BibTex]