Example-based control of human motion

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (p. 41-43).In human motion control applications, the mapping between a control specification and an appropriate target motion often defies an explicit encoding. This thesis presents a method that allows such a mapping to be defined by example, given that the control specification is recorded motion. The method begins by building a database of semantically meaningful instances of the mapping, each of which is represented by synchronized segments of control and target motion. A dynamic programming algorithm can then be used to interpret an input control specification in terms of mapping instances. This interpretation induces a sequence of target segments from the database, which is concatenated to create the appropriate target motion. The method is evaluated on two examples of indirect control. In the first, it is used to synthesize a walking human character that follows a sampled trajectory. In the second, it is used generate a synthetic partner for a dancer whose motion is acquired through motion capture.by Eugene Hsu.S.M

Guided Time Warping for Motion Editing

Time warping allows users to modify timing without affecting poses. It has many applications in animation systems for motion editing, such as refining motions to meet new timing constraints or modifying the acting of animated characters. However, time warping typically requires many manual adjustments to achieve the desired results. We present a technique which simplifies this process by allowing time warps to be guided by a provided reference motion. Given few timing constraints, it computes a warp that both satisfies these constraints and maximizes local timing similarities to the reference. The algorithm is fast enough to incorporate into standard animation workflows. We apply the technique to two common tasks: preserving the natural timing of motions under new time constraints and modifying the timing of motions for stylistic effects.Singapore-MIT GAMBIT Game La

A comparison of classification methods for predicting Chronic Fatigue Syndrome based on genetic data

Background: In the studies of genomics, it is essential to select a small number of genes that are more significant than the others for the association studies of disease susceptibility. In this work, our goal was to compare computational tools with and without feature selection for predicting chronic fatigue syndrome (CFS) using genetic factors such as single nucleotide polymorphisms ( SNPs). Methods: We employed the dataset that was original to the previous study by the CDC Chronic Fatigue Syndrome Research Group. To uncover relationships between CFS and SNPs, we applied three classification algorithms including naive Bayes, the support vector machine algorithm, and the C4.5 decision tree algorithm. Furthermore, we utilized feature selection methods to identify a subset of influential SNPs. One was the hybrid feature selection approach combining the chi-squared and information-gain methods. The other was the wrapper- based feature selection method. Results: The naive Bayes model with the wrapper-based approach performed maximally among predictive models to infer the disease susceptibility dealing with the complex relationship between CFS and SNPs. Conclusion: We demonstrated that our approach is a promising method to assess the associations between CFS and SNPs

Press-fit hinge and magnesium alloy enclosure for laptop cover attachment

Computing devices such as laptops utilize hinges to connect the lid of the device to its base. This disclosure describes a press-fit hinge mechanism for use in conjunction with magnesium alloy based enclosures that are utilized to attach a computing device lid to its base. The press-fit hinge mechanism includes a knurled shaft designed to be inserted into a magnesium alloy based enclosure. The teeth and lead-in chamfer geometry of the knurled shaft are designed to control the interference between the knurls and enclosure opening. A straight knurl pattern is utilized for ease of manufacture, and provides for better material flow via ridges of the knurled shaft, a lower insertion force, and a higher torsional resistance. The press-fit hinge mechanism enables tighter assembly tolerances, smaller assembly gaps and improved appearance for the device

Targeting RyR Activity Boosts Antisense Exon 44 and 45 Skipping in Human DMD Skeletal or Cardiac Muscle Culture Models.

Systemic delivery of antisense oligonucleotides (AO) for DMD exon skipping has proven effective for reframing DMD mRNA, rescuing dystrophin expression, and slowing disease progression in animal models. In humans with Duchenne muscular dystrophy treated with AOs, low levels of dystrophin have been induced, and modest slowing of disease progression has been observed, highlighting the need for improved efficiency of human skipping drugs. Here, we demonstrate that dantrolene and Rycals S107 and ARM210 potentiate AO-mediated exon skipping of exon 44 or exon 45 in patient-derived myotube cultures with appropriate mutations. Further, dantrolene is shown to boost AO-mediated exon skipping in patient-derived, induced cardiomyocyte cultures. Our findings further validate the ryanodine receptors (RyR) as the likely target responsible for exon skip boosting and demonstrate potential applicability beyond exon 51 skipping. These data provide preclinical support of dantrolene trial as an adjuvant to AO-mediated exon-skipping therapy in humans and identify a novel Rycal, ARM210, for development as a potential exon-skipping booster. Further, they highlight the value of mutation-specific DMD culture models for basic discovery, preclinical drug screening and translation of personalized genetic medicines

Motion transformation by example

Includes bibliographical references (p. 71-77).Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Animated characters bring the illusion of life to feature films, television shows, video games, and educational simulations. However, it is difficult for artists to define natural and expressive movement. This challenge is compounded by the fact that people are intrinsically sensitive to subtle inaccuracies in human motion. To address this problem, this thesis presents techniques that adjust existing character animations to meet new stylistic or temporal requirements. The proposed methods learn compact models of the appropriate transformations from examples provided by the user. By doing so, they are able to achieve compelling results without significant user effort or skill.by Eugene Hsu.Ph.D

Cross-Resolution Flow Propagation for Foveated Video Super-Resolution

The demand of high-resolution video contents has grown over the years. However, the delivery of high-resolution video is constrained by either computational resources required for rendering or network bandwidth for remote transmission. To remedy this limitation, we leverage the eye trackers found alongside existing augmented and virtual reality headsets. We propose the application of video super-resolution (VSR) technique to fuse low-resolution context with regional high-resolution context for resource-constrained consumption of high-resolution content without perceivable drop in quality. Eye trackers provide us the gaze direction of a user, aiding us in the extraction of the regional high-resolution context. As only pixels that falls within the gaze region can be resolved by the human eye, a large amount of the delivered content is redundant as we can't perceive the difference in quality of the region beyond the observed region. To generate a visually pleasing frame from the fusion of high-resolution region and low-resolution region, we study the capability of a deep neural network of transferring the context of the observed region to other regions (low-resolution) of the current and future frames. We label this task a Foveated Video Super-Resolution (FVSR), as we need to super-resolve the low-resolution regions of current and future frames through the fusion of pixels from the gaze region. We propose Cross-Resolution Flow Propagation (CRFP) for FVSR. We train and evaluate CRFP on REDS dataset on the task of 8x FVSR, i.e. a combination of 8x VSR and the fusion of foveated region. Departing from the conventional evaluation of per frame quality using SSIM or PSNR, we propose the evaluation of past foveated region, measuring the capability of a model to leverage the noise present in eye trackers during FVSR. Code is made available at https://github.com/eugenelet/CRFP.Comment: 12 pages, 8 figures, to appear in IEEE/CVF Winter Conference on Applications of Computer Vision (WACV) 202

Energy and Angular Distributions of Electrons from Ion Impact on Atomic and Molecular Hydrogen. I. 20- 114-keV H\u3csup\u3e+\u3c/sup\u3e + H\u3csub\u3e2\u3c/sub\u3e

Apparatus and procedures are described for the measurement of absolute cross sections, differential in ejected electron energy and angle, for ionization of atomic and molecular hydrogen by ion impact. A hemispherical electrostatic energy analyzer, rotatable from 15° to 165° with respect to the direction of the incident ion beam, was used to measure energy spectra of secondary electrons from 1.5 to 300 eV. Cross sections at ten angles (nine at some energies) and five incident-ion energies from 20 to 114 keV for H+ +H2 collisions are given. The doubly differential cross sections were integrated over angle and electron energy to obtain singly differential and total-ionization cross sections. The uncertainty in the doubly differential cross sections is 21% at a secondary energy of 1.5 eV decreasing to 18% at 10 eV and above. The total cross sections have a rms deviation of 12% from recommended values. A broad peak at 6 eV in the energy spectrum of electrons from low-energy H+ +H2 collisions is attributed to autoionization

Speech Resynthesis from Discrete Disentangled Self-Supervised Representations

We propose using self-supervised discrete representations for the task of speech resynthesis. To generate disentangled representation, we separately extract low-bitrate representations for speech content, prosodic information, and speaker identity. This allows to synthesize speech in a controllable manner. We analyze various state-of-the-art, self-supervised representation learning methods and shed light on the advantages of each method while considering reconstruction quality and disentanglement properties. Specifically, we evaluate the F0 reconstruction, speaker identification performance (for both resynthesis and voice conversion), recordings' intelligibility, and overall quality using subjective human evaluation. Lastly, we demonstrate how these representations can be used for an ultra-lightweight speech codec. Using the obtained representations, we can get to a rate of 365 bits per second while providing better speech quality than the baseline methods. Audio samples can be found under the following link: speechbot.github.io/resynthesis.Comment: In Proceedings of Interspeech 202