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2007


A Database and Evaluation Methodology for Optical Flow
A Database and Evaluation Methodology for Optical Flow

Baker, S., Scharstein, D., Lewis, J.P., Roth, S., Black, M.J., Szeliski, R.

In Int. Conf. on Computer Vision, ICCV, pages: 1-8, Rio de Janeiro, Brazil, October 2007 (inproceedings)

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pdf [BibTex]

2007


pdf [BibTex]


Shining a light on human pose: On shadows, shading and the estimation of pose and shape,
Shining a light on human pose: On shadows, shading and the estimation of pose and shape,

Balan, A., Black, M. J., Haussecker, H., Sigal, L.

In Int. Conf. on Computer Vision, ICCV, pages: 1-8, Rio de Janeiro, Brazil, October 2007 (inproceedings)

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pdf YouTube [BibTex]

pdf YouTube [BibTex]


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Ensemble spiking activity as a source of cortical control signals in individuals with tetraplegia

Simeral, J. D., Kim, S. P., Black, M. J., Donoghue, J. P., Hochberg, L. R.

Biomedical Engineering Society, BMES, september 2007 (conference)

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[BibTex]

[BibTex]


Detailed human shape and pose from images
Detailed human shape and pose from images

Balan, A., Sigal, L., Black, M. J., Davis, J., Haussecker, H.

In IEEE Conf. on Computer Vision and Pattern Recognition, CVPR, pages: 1-8, Minneapolis, June 2007 (inproceedings)

Abstract
Much of the research on video-based human motion capture assumes the body shape is known a priori and is represented coarsely (e.g. using cylinders or superquadrics to model limbs). These body models stand in sharp contrast to the richly detailed 3D body models used by the graphics community. Here we propose a method for recovering such models directly from images. Specifically, we represent the body using a recently proposed triangulated mesh model called SCAPE which employs a low-dimensional, but detailed, parametric model of shape and pose-dependent deformations that is learned from a database of range scans of human bodies. Previous work showed that the parameters of the SCAPE model could be estimated from marker-based motion capture data. Here we go further to estimate the parameters directly from image data. We define a cost function between image observations and a hypothesized mesh and formulate the problem as optimization over the body shape and pose parameters using stochastic search. Our results show that such rich generative models enable the automatic recovery of detailed human shape and pose from images.

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pdf YouTube [BibTex]

pdf YouTube [BibTex]


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Learning static Gestalt laws through dynamic experience

Ostrovsky, Y., Wulff, J., Sinha, P.

Journal of Vision, 7(9):315-315, ARVO, June 2007 (article)

Abstract
The Gestalt laws (Wertheimer 1923) are widely regarded as the rules that help us parse the world into objects. However, it is unclear as to how these laws are acquired by an infant's visual system. Classically, these “laws” have been presumed to be innate (Kellman and Spelke 1983). But, more recent work in infant development, showing the protracted time-course over which these grouping principles emerge (e.g., Johnson and Aslin 1995; Craton 1996), suggests that visual experience might play a role in their genesis. Specifically, our studies of patients with late-onset vision (Project Prakash; VSS 2006) and evidence from infant development both point to an early role of common motion cues for object grouping. Here we explore the possibility that the privileged status of motion in the developmental timeline is not happenstance, but rather serves to bootstrap the learning of static Gestalt cues. Our approach involves computational analyses of real-world motion sequences to investigate whether primitive optic flow information is correlated with static figural cues that could eventually come to serve as proxies for grouping in the form of Gestalt principles. We calculated local optic flow maps and then examined how similarity of motion across image patches co-varied with similarity of certain figural properties in static frames. Results indicate that patches with similar motion are much more likely to have similar luminance, color, and orientation as compared to patches with dissimilar motion vectors. This regularity suggests that, in principle, common motion extracted from dynamic visual experience can provide enough information to bootstrap region grouping based on luminance and color and contour continuation mechanisms in static scenes. These observations, coupled with the cited experimental studies, lend credence to the hypothesis that static Gestalt laws might be learned through a bootstrapping process based on early dynamic experience.

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link (url) DOI [BibTex]

link (url) DOI [BibTex]


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The power of external mentors for women pursuing academic careers in engineering and science: Stories of MentorNet ACE and its Proteges and Mentors

Muller, C. B., Smith, E. H. B., Chou-Green, J., Daniels-Race, T., Drummond, A., Kuchenbecker, K. J.

In Proc. Women in Engineering Programs and Advocates Network (WEPAN) National Conference, Lake Buena Vista, Florida, USA, June 2007, Oral presentation given by Muller (inproceedings)

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[BibTex]

[BibTex]


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Effects of Visual and Proprioceptive Position Feedback on Human Control of Targeted Movement

Kuchenbecker, K. J., Gurari, N., Okamura, A. M.

In Proc. IEEE International Conference on Rehabilitation Robotics, pages: 513-524, Noordwijk, Netherlands, June 2007, Oral and poster presentations given by Kuchenbecker (inproceedings)

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[BibTex]

[BibTex]


Decoding grasp aperture from motor-cortical population activity
Decoding grasp aperture from motor-cortical population activity

Artemiadis, P., Shakhnarovich, G., Vargas-Irwin, C., Donoghue, J. P., Black, M. J.

In The 3rd International IEEE EMBS Conference on Neural Engineering, pages: 518-521, May 2007 (inproceedings)

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pdf [BibTex]

pdf [BibTex]


Multi-state decoding of point-and-click control signals from motor cortical activity in a human with tetraplegia
Multi-state decoding of point-and-click control signals from motor cortical activity in a human with tetraplegia

Kim, S., Simeral, J., Hochberg, L., Donoghue, J. P., Friehs, G., Black, M. J.

In The 3rd International IEEE EMBS Conference on Neural Engineering, pages: 486-489, May 2007 (inproceedings)

Abstract
Basic neural-prosthetic control of a computer cursor has been recently demonstrated by Hochberg et al. [1] using the BrainGate system (Cyberkinetics Neurotechnology Systems, Inc.). While these results demonstrate the feasibility of intracortically-driven prostheses for humans with paralysis, a practical cursor-based computer interface requires more precise cursor control and the ability to “click” on areas of interest. Here we present a practical point and click device that decodes both continuous states (e.g. cursor kinematics) and discrete states (e.g. click state) from single neural population in human motor cortex. We describe a probabilistic multi-state decoder and the necessary training paradigms that enable point and click cursor control by a human with tetraplegia using an implanted microelectrode array. We present results from multiple recording sessions and quantify the point and click performance.

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pdf [BibTex]

pdf [BibTex]


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Quantifying the value of visual and haptic position feedback in force-based motion control

Kuchenbecker, K. J., Gurari, N., Okamura, A. M.

In Proc. IEEE World Haptics Conference, pages: 561-562, Tsukuba, Japan, March 2007, Poster presentation given by Kuchenbecker (inproceedings)

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[BibTex]

[BibTex]


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Comparing Visual and Haptic Position Feedback

Kuchenbecker, K. J., Gurari, N., Okamura, A. M.

Hands-on demonstration at IEEE World Haptics Conference, Tsukuba, Japan, March 2007 (misc)

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[BibTex]

[BibTex]


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Shaping event-based haptic transients via an improved understanding of real contact dynamics

Fiene, J. P., Kuchenbecker, K. J.

In Proc. IEEE World Haptics Conference, pages: 170-175, Tsukuba, Japan, March 2007, Oral presentation given by Fiene. {B}est Haptic Technology Paper Award (inproceedings)

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[BibTex]

[BibTex]


Neuromotor prosthesis development
Neuromotor prosthesis development

Donoghue, J., Hochberg, L., Nurmikko, A., Black, M., Simeral, J., Friehs, G.

Medicine & Health Rhode Island, 90(1):12-15, January 2007 (article)

Abstract
Article describes a neuromotor prosthesis (NMP), in development at Brown University, that records human brain signals, decodes them, and transforms them into movement commands. An NMP is described as a system consisting of a neural interface, a decoding system, and a user interface, also called an effector; a closed-loop system would be completed by a feedback signal from the effector to the brain. The interface is based on neural spiking, a source of information-rich, rapid, complex control signals from the nervous system. The NMP described, named BrainGate, consists of a match-head sized platform with 100 thread-thin electrodes implanted just into the surface of the motor cortex where commands to move the hand emanate. Neural signals are decoded by a rack of computers that displays the resultant output as the motion of a cursor on a computer monitor. While computer cursor motion represents a form of virtual device control, this same command signal could be routed to a device to command motion of paralyzed muscles or the actions of prosthetic limbs. The researchers’ overall goal is the development of a fully implantable, wireless multi-neuron sensor for broad research, neural prosthetic, and human neurodiagnostic applications.

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pdf [BibTex]

pdf [BibTex]


Frequency-domain displacement sensing with a fiber ring-resonator containing a variable gap
Frequency-domain displacement sensing with a fiber ring-resonator containing a variable gap

Vollmer, F., Fischer, P.

SENSORS AND ACTUATORS A-PHYSICAL, 134(2):410-413, 2007 (article)

Abstract
Ring-resonators are in general not amenable to strain-free (non-contact) displacement measurements. We show that this limitation may be overcome if the ring-resonator, here a fiber-loop, is designed to contain a gap, such that the light traverses a free-space part between two aligned waveguide ends. Displacements are determined with nanometer sensitivity by measuring the associated changes in the resonance frequencies. Miniaturization should increase the sensitivity of the ring-resonator interferometer. Ring geometries that contain an optical circulator can be used to profile reflective samples. (c) 2006 Elsevier B.V. All rights reserved.

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DOI [BibTex]

DOI [BibTex]


Observation of the Faraday effect via beam deflection in a longitudinal magnetic field
Observation of the Faraday effect via beam deflection in a longitudinal magnetic field

Ghosh, A., Hill, W., Fischer, P.

PHYSICAL REVIEW A, 76(5), 2007 (article)

Abstract
We show that magnetic-field-induced circular differential deflection of light can be observed in reflection or refraction at a single interface. The difference in the reflection or refraction angles between the two circular polarization components is a function of the magnetic-field strength and the Verdet constant, and permits the observation of the Faraday effect not via polarization rotation in transmission, but via changes in the propagation direction. Deflection measurements do not suffer from n-pi ambiguities and are shown to be another means to map magnetic fields with high axial resolution, or to determine the sign and magnitude of magnetic-field pulses in a single measurement.

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DOI [BibTex]


Circular differential double diffraction in chiral media
Circular differential double diffraction in chiral media

Ghosh, A., Fazal, F. M., Fischer, P.

OPTICS LETTERS, 32(13):1836-1838, 2007 (article)

Abstract
In an optically active liquid the diffraction angle depends on the circular polarization state of the incident light beam. We report the observation of circular differential diffraction in an isotropic chiral medium, and we demonstrate that double diffraction is an alternate means to determine the handedness (enantiomeric excess) of a solution. (c) 2007 Optical Society of America.

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DOI [BibTex]

DOI [BibTex]


On the spatial statistics of optical flow
On the spatial statistics of optical flow

Roth, S., Black, M. J.

International Journal of Computer Vision, 74(1):33-50, 2007 (article)

Abstract
We present an analysis of the spatial and temporal statistics of "natural" optical flow fields and a novel flow algorithm that exploits their spatial statistics. Training flow fields are constructed using range images of natural scenes and 3D camera motions recovered from hand-held and car-mounted video sequences. A detailed analysis of optical flow statistics in natural scenes is presented and machine learning methods are developed to learn a Markov random field model of optical flow. The prior probability of a flow field is formulated as a Field-of-Experts model that captures the spatial statistics in overlapping patches and is trained using contrastive divergence. This new optical flow prior is compared with previous robust priors and is incorporated into a recent, accurate algorithm for dense optical flow computation. Experiments with natural and synthetic sequences illustrate how the learned optical flow prior quantitatively improves flow accuracy and how it captures the rich spatial structure found in natural scene motion.

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pdf preprint pdf from publisher [BibTex]

pdf preprint pdf from publisher [BibTex]


Deterministic Annealing for Multiple-Instance Learning
Deterministic Annealing for Multiple-Instance Learning

Gehler, P., Chapelle, O.

In Artificial Intelligence and Statistics (AIStats), 2007 (inproceedings)

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pdf [BibTex]

pdf [BibTex]


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Point-and-click cursor control by a person with tetraplegia using an intracortical neural interface system

Kim, S., Simeral, J. D., Hochberg, L. R., Friehs, G., Donoghue, J. P., Black, M. J.

Program No. 517.2. 2007 Abstract Viewer and Itinerary Planner, Society for Neuroscience, San Diego, CA, 2007, Online (conference)

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[BibTex]

[BibTex]


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Hydrogen storage in metal-organic frameworks

Hirscher, M., Panella, B.

{Scripta Materialia}, 56, pages: 809-812, 2007 (article)

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[BibTex]

[BibTex]


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Substrate-induced current anisotropy in YBa2Cu3O7-δthin films

Djupmyr, M., Albrecht, J.

{Physica C}, 460-462, pages: 1190-1191, 2007 (article)

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DOI [BibTex]

DOI [BibTex]


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A micellar approach to magnetic ultrahigh-density data-storage media: extending the limits of current colloidal methods

Ethirajan, A., Wiedwald, U., Boyen, H.-G., Kern, B., Han, L., Klimmer, A., Weigl, F., Kästle, G., Ziemann, P., Fauth, K., Cai, J., Behm, J., Romanyuk, A., Oelhafen, P., Walther, P., Biskupek, J., Kaiser, U.

{Advanced Materials}, 19, pages: 406-410, 2007 (article)

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[BibTex]

[BibTex]


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Size dependence in the magnetization reversal of Fe/Gd multilayers on self-assembled arrays of nanospheres

Amaladass, E., Ludescher, B., Schütz, G., Tyliszczak, T., Eimüller, T.

{Applied Physics Letters}, 91, 2007 (article)

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DOI [BibTex]

DOI [BibTex]


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Ma\ssgeschneiderte Wasserstoffspeicher

Hirscher, M., Panella, B.

{Nachrichten aus der Gdch-Energieinitiative}, (Sonderheft April 2007):12-13, 2007 (article)

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[BibTex]

[BibTex]


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Reconstruction of historical alloys for pipe organs brings true Baroque music back to life.

Baretzky, B., Friesel, M., Straumal, B.

{MRS Bulletin}, 32, pages: 249-255, 2007 (article)

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[BibTex]

[BibTex]


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Analysis of results from X-ray magnetic reflectometry for magnetic multilayer systems

Fähnle, M., Steiauf, D., Martosiswoyo, L., Goering, E., Brück, S., Schütz, G.

{Physical Review B}, 75, 2007 (article)

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[BibTex]

[BibTex]


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Dramatic role of critical current anisotropy on flux avalanches in MgB2 films

Albrecht, J., Matveev, A. T., Strempfer, J., Habermeier, H.-U., Shantsev, D. V., Galperin, Y. M., Johansen, T. H.

{Physical Review Letters}, 98, 2007 (article)

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[BibTex]

[BibTex]


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Transport properties of LCMO/YBCO hybrid structures

Soltan, S., Albrecht, J., Habermeier, H.-U.

{Materials Science and Engineering B}, 144, pages: 15-18, 2007 (article)

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DOI [BibTex]

DOI [BibTex]


Assistive technology and robotic control using {MI} ensemble-based neural interface systems in humans with tetraplegia
Assistive technology and robotic control using MI ensemble-based neural interface systems in humans with tetraplegia

Donoghue, J. P., Nurmikko, A., Black, M. J., Hochberg, L.

Journal of Physiology, Special Issue on Brain Computer Interfaces, 579, pages: 603-611, 2007 (article)

Abstract
This review describes the rationale, early stage development, and initial human application of neural interface systems (NISs) for humans with paralysis. NISs are emerging medical devices designed to allowpersonswith paralysis to operate assistive technologies or to reanimatemuscles based upon a command signal that is obtained directly fromthe brain. Such systems require the development of sensors to detect brain signals, decoders to transformneural activity signals into a useful command, and an interface for the user.We review initial pilot trial results of an NIS that is based on an intracortical microelectrode sensor that derives control signals from the motor cortex.We review recent findings showing, first, that neurons engaged by movement intentions persist in motor cortex years after injury or disease to the motor system, and second, that signals derived from motor cortex can be used by persons with paralysis to operate a range of devices. We suggest that, with further development, this form of NIS holds promise as a useful new neurotechnology for those with limited motor function or communication.We also discuss the additional potential for neural sensors to be used in the diagnosis and management of various neurological conditions and as a new way to learn about human brain function.

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pdf preprint pdf from publisher DOI [BibTex]

pdf preprint pdf from publisher DOI [BibTex]


Learning Appearances with Low-Rank SVM
Learning Appearances with Low-Rank SVM

Wolf, L., Jhuang, H., Hazan, T.

In Conference on Computer Vision and Pattern Recognition (CVPR), 2007 (inproceedings)

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pdf [BibTex]

pdf [BibTex]


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Neural correlates of grip aperture in primary motor cortex

Vargas-Irwin, C., Shakhnarovich, G., Artemiadis, P., Donoghue, J. P., Black, M. J.

Program No. 517.10. 2007 Abstract Viewer and Itinerary Planner, Society for Neuroscience, San Diego, CA, 2007, Online (conference)

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[BibTex]

[BibTex]


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Directional tuning in motor cortex of a person with ALS

Simeral, J. D., Donoghue, J. P., Black, M. J., Friehs, G. M., Brown, R. H., Krivickas, L. S., Hochberg, L. R.

Program No. 517.4. 2007 Abstract Viewer and Itinerary Planner, Society for Neuroscience, San Diego, CA, 2007, Online (conference)

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[BibTex]

[BibTex]


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Cluster expansions in multicomponent systems: precise expansions from noisy databases

Diaz-Ortiz, A., Dosch, H., Drautz, R.

{Journal of Physics: Condensed Matter}, 19, 2007 (article)

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DOI [BibTex]

DOI [BibTex]


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Unusual propagation of magnetic avalanches in gold covered MgB2

Albrecht, J., Matveev, A. T., Habermeier, H.-U.

{Physica C}, 460-462, pages: 1245-1246, 2007 (article)

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DOI [BibTex]

DOI [BibTex]


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Lowering of the L10 ordering temperature of FePt nanoparticles by He+ ion irradiation

Wiedwald, U., Klimmer, A., Kern, B., Han, L., Boyen, H.-G., Ziemann, P., Fauth, K.

{Applied Physics Letters}, 90, 2007 (article)

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[BibTex]

[BibTex]


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Magnetic core shell nanoparticles characterized by X-ray absorption and magnetic circular dichroism

Fauth, K.

{Modern Physics Letters B}, 21(18):1179-1187, 2007 (article)

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[BibTex]

[BibTex]


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Magnetic moment of Fe in oxide-free FePt nanoparticles

Dmitrieva, O., Spasova, M., Antoniak, C., Acet, M., Dumpich, G., Kästner, J., Farle, M., Fauth, K., Wiedwald, U., Boyen, H.-G., Ziemann, P.

{Physical Review B}, 76, 2007 (article)

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[BibTex]

[BibTex]


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The effect of bismuth segregation on the faceting of \Sigma3 and \Sigma9 coincidence boundaries in copper bicrystals

Straumal, B. B., Polyakov, S. A., Chang, L.-S., Mittemeijer, E. J.

{International Journal of Materials Research}, 98, pages: 451-456, 2007 (article)

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[BibTex]

[BibTex]


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Hot isostatic pressing of Cu-Bi polycrystals with liquid-like grain boundary layers

Chang, L.-S., Straumal, B., Rabkin, E., Lojkowski, W., Gust, W.

{Acta Materialia}, 55, pages: 335-343, 2007 (article)

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[BibTex]

[BibTex]


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Spatially resolved magnetic response in core shell nanoparticles

Fauth, K., Goering, E., Theil Kuhn, L.

{Modern Physics Letters B}, 21(18):1197-1200, 2007 (article)

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[BibTex]

[BibTex]


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Interfaces in semiconductor/metal radial superlattices

Deneke, C., Sigle, W., Eigenthaler, U., van Aken, P. A., Schütz, G., Schmidt, O. G.

{Applied Physics Letters}, 90, 2007 (article)

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[BibTex]

[BibTex]


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Live cell adhesion assay with attenuated total reflection infrared spectroscopy

Schmidt, M., Wolfram, T., Rumpler, M., Tripp, C. P., Grunze, M.

{Biointerphases}, 2(1):1-5, 2007 (article)

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[BibTex]

[BibTex]


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Unusual Co moment reduction in the NiCoO/Co exchange bias system

Brück, S., Goering, E., Tang, Y. J., Schütz, G., Berkowitz, A. E.

{Journal of Magnetism and Magnetic Materials}, 310, pages: 2316-2318, 2007 (article)

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[BibTex]

[BibTex]


Steerable random fields
Steerable random fields

(Best Paper Award, INI-Graphics Net, 2008)

Roth, S., Black, M. J.

In Int. Conf. on Computer Vision, ICCV, pages: 1-8, Rio de Janeiro, Brazil, 2007 (inproceedings)

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pdf [BibTex]

pdf [BibTex]


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Toward standardized assessment of pointing devices for brain-computer interfaces

Donoghue, J., Simeral, J., Kim, S., G.M. Friehs, L. H., Black, M.

Program No. 517.16. 2007 Abstract Viewer and Itinerary Planner, Society for Neuroscience, San Diego, CA, 2007, Online (conference)

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[BibTex]

[BibTex]


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Ab initio calculations of adiabatic magnon spectra using the atomic-sphere aproximation for the spin direction

Singer, R., Dietermann, F., Steiauf, D., Fähnle, M.

{Physical Review B}, 76, 2007 (article)

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DOI [BibTex]

DOI [BibTex]


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Low-temperature thermal-desorption mass spectroscopy applied to investigate the hydrogen adsorption on porous materials

Panella, B., Hirscher, M., Ludescher, B.

{Microporous and Mesoporous Materials}, 103, pages: 230-234, 2007 (article)

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[BibTex]