23,546 research outputs found
MOHO: Learning Single-view Hand-held Object Reconstruction with Multi-view Occlusion-Aware Supervision
Previous works concerning single-view hand-held object reconstruction
typically utilize supervision from 3D ground truth models, which are hard to
collect in real world. In contrast, abundant videos depicting hand-object
interactions can be accessed easily with low cost, although they only give
partial object observations with complex occlusion. In this paper, we present
MOHO to reconstruct hand-held object from a single image with multi-view
supervision from hand-object videos, tackling two predominant challenges
including object's self-occlusion and hand-induced occlusion. MOHO inputs
semantic features indicating visible object parts and geometric embeddings
provided by hand articulations as partial-to-full cues to resist object's
self-occlusion, so as to recover full shape of the object. Meanwhile, a novel
2D-3D hand-occlusion-aware training scheme following the synthetic-to-real
paradigm is proposed to release hand-induced occlusion. In the synthetic
pre-training stage, 2D-3D hand-object correlations are constructed by
supervising MOHO with rendered images to complete the hand-concealed regions of
the object in both 2D and 3D space. Subsequently, MOHO is finetuned in real
world by the mask-weighted volume rendering supervision adopting hand-object
correlations obtained during pre-training. Extensive experiments on HO3D and
DexYCB datasets demonstrate that 2D-supervised MOHO gains superior results
against 3D-supervised methods by a large margin. Codes and key assets will be
released soon
Long-range concealed object detection through active covert illumination
© 2015 SPIE. When capturing a scene for surveillance, the addition of rich 3D data can dramatically improve the accuracy of object detection or face recognition. Traditional 3D techniques, such as geometric stereo, only provide a coarse grained reconstruction of the scene and are ill-suited to fine analysis. Photometric stereo is a well established technique providing dense, high-resolution, reconstructions, using active artificial illumination of an object from multiple directions to gather surface information. It is typically used indoors, at short range
High-resolution, slant-angle scene generation and validation of concealed targets in DIRSIG
Traditionally, synthetic imagery has been constructed to simulate images captured with low resolution, nadir-viewing sensors. Advances in sensor design have driven a need to simulate scenes not only at higher resolutions but also from oblique view angles. The primary efforts of this research include: real image capture, scene construction and modeling, and validation of the synthetic imagery in the reflective portion of the spectrum. High resolution imagery was collected of an area named MicroScene at the Rochester Institute of Technology using the Chester F. Carlson Center for Imaging Science\u27s MISI and WASP sensors using an oblique view angle. Three Humvees, the primary targets, were placed in the scene under three different levels of concealment. Following the collection, a synthetic replica of the scene was constructed and then rendered with the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model configured to recreate the scene both spatially and spectrally based on actual sensor characteristics. Finally, a validation of the synthetic imagery against the real images of MicroScene was accomplished using a combination of qualitative analysis, Gaussian maximum likelihood classification, grey-level co-occurrence matrix derived texture metrics, and the RX algorithm. The model was updated following each validation using a cyclical development approach. The purpose of this research is to provide a level of confidence in the synthetic imagery produced by DIRSIG so that it can be used to train and develop algorithms for real world concealed target detection
Beyond simulation: designing for uncertainty and robust solutions
Simulation is an increasingly essential tool in the design of our environment, but any model is only as good as the initial assumptions on which it is built. This paper aims to outline some of the limits and potential dangers of reliance on simulation, and suggests how to make our models, and our buildings, more robust with respect to the uncertainty we face in design. It argues that the single analyses provided by most simulations display too precise and too narrow a result to be maximally useful in design, and instead a broader description is required, as might be provided by many differing simulations. Increased computing power now allows this in many areas. Suggestions are made for the further development of simulation tools for design, in that these increased resources should be dedicated not simply to the accuracy of single solutions, but to a bigger picture that takes account of a design’s robustness to change, multiple phenomena that cannot be predicted, and the wider range of possible solutions. Methods for doing so, including statistical methods, adaptive modelling, machine learning and pattern recognition algorithms for identifying persistent structures in models, will be identified. We propose a number of avenues for future research and how these fit into design process, particularly in the case of the design of very large buildings
AN INVESTIGATION OF DIFFERENT VIDEO WATERMARKING TECHNIQUES
Watermarking is an advanced technology that identifies to solve the problem of illegal manipulation and distribution of digital data. It is the art of hiding the copyright information into host such that the embedded data is imperceptible. The covers in the forms of digital multimedia object, namely image, audio and video. The extensive literature collected related to the performance improvement of video watermarking techniques is critically reviewed and presented in this paper. Also, comprehensive review of the literature on the evolution of various video watermarking techniques to achieve robustness and to maintain the quality of watermarked video sequences
Flight simulator for hypersonic vehicle and a study of NASP handling qualities
The research goal of the Human-Machine Systems Engineering Group was to study the existing handling quality studies in aircraft with sonic to supersonic speeds and power in order to understand information requirements needed for a hypersonic vehicle flight simulator. This goal falls within the NASA task statements: (1) develop flight simulator for hypersonic vehicle; (2) study NASP handling qualities; and (3) study effects of flexibility on handling qualities and on control system performance. Following the above statement of work, the group has developed three research strategies. These are: (1) to study existing handling quality studies and the associated aircraft and develop flight simulation data characterization; (2) to develop a profile for flight simulation data acquisition based on objective statement no. 1 above; and (3) to develop a simulator and an embedded expert system platform which can be used in handling quality experiments for hypersonic aircraft/flight simulation training
Creation of an Experimental Engineering Toolbox for the Digital Transformation of Manual Jet Engine Assembly
The fast and safe motion of goods and people is one of the foundations of the modern world. Jet aircraft is the fastest transport at the moment along with high-speed trains. Accordingly, both production and maintenance of aircrafts are an important task of our modern industrial environment as well. Modern aircraft engines require appropriate care and understanding of design and manufacturing. This is even more important, as the production of aerospace engines remains a manual process in many cases with limited data sources. Thus, quality control will need to take into account verification of manufacturing and assembly steps through specific checks and controls whilst implementing additional data sources. Automation of tasks still is at a low level. In this article a review of the challenges with regard to controls, automation and process and technical understanding for aerospace engine production and repair is provided. As this requires the collaboration of many teams and partners, an improvement and step change towards deeper understanding and process efficiency is required. As many operations remain manual, innovations for how humans interact with the technology and collaborate with an industrial environment are needed. The project in this article demonstrates the creation and usage of the proposed solutions for collaboration, troubleshooting and error correction
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