55 research outputs found
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A Comparison of Image Aligning and Correcting Software with an Unmanned Aerial System
In the past few decades, many kinds of UAS for image acquisition have been developed. But software for image aligning and correcting is mostly high-cost commercial. This problem caused the cost-problem in using UAS. Nowadays, a variety of software, not only commercial but also open-source, provides powerful image processing tool. There are a number of software to support image processing. In this study,five popular programs are tested for comparison. The goal of this study is to compare popular open-source software based on the ease use, overall accuracy and processing time for chunk of images from UAS
FEATURES OF 2017A AND AlSi9Mg ALUMINUM ALLOYS FRICTION STIR WELDED WITH ROOT-SIDE HEATING
Aluminum alloys 2017A and AlSi9Mg (hypo-eutectic silumin) were friction stir welded with a relatively high linear velocity (over 1 m/min) and use of an additional heat source from the root side of the weld. Macrostructure investigation (with high-resolution images) showed no effect of heating on weld quality. The welding process caused significant fragmentation of the secondary phases in the AlSi9Mg alloy. Furthermore, it was proven that the material above the weld nugget was not mixed and contained micro-defects that were not caused by welding. Also, it contained cavities on the boundaries between Si-particles and the matrix. Based on hardness distribution, a slight strengthening of the cast alloy was observed at the bottom and middle parts of the weld. However, the hardness of the 2017A alloy initially decreased and then increased due to natural aging. This means that the FSW process produced a metastable state in the alloy
Automatic seagrass detection: A survey
© 2017 IEEE. Seagrass is an important component of the marine ecosystem and plays a vital role in preserving the water quality. The traditional approaches for sea grass identification are either manual or semi-automated, resulting in costlier, time consuming and tedious solutions. There has been an increasing interest in the automatic identification of seagrasses and this article provides a survey of automatic classification techniques that are based on machine learning, fuzzy synthetic evaluation model and maximum likelihood classifier along with their performance. The article classifies the existing approaches on the basis of image types (i.e. aerial, satellite, and underwater digital), outlines the current challenges and provides future research directions
Active Materials for Medical Applications
This Special Issue was proposed by and for engineers, physicists, medical doctors, researchers and scientists. We intend to analyze and discuss different topics on special materials for medical applications. There is great potential in the application of active or smart materials (metallic, polymer or ceramic) for the progression of applications in the medical domain of MEMS, actuators, sensors or functional systems. Active or “smart” materials have the ability to respond to different physical or chemical stimuli in a specific, repeatable mode. The actual activity in the domain, however, presents problems connected to obtaining, processing, characterizing, modeling and simulating or prototyping technologies. This Special Issue focuses on the most recent advances in obtaining and thermal and mechanical processing active materials used in the medical field with enhanced performances
Automated inverse-rendering techniques for realistic 3D artefact compositing in 2D photographs
PhD ThesisThe process of acquiring images of a scene and modifying the defining structural features
of the scene through the insertion of artefacts is known in literature as compositing. The
process can take effect in the 2D domain (where the artefact originates from a 2D image
and is inserted into a 2D image), or in the 3D domain (the artefact is defined as a dense
3D triangulated mesh, with textures describing its material properties).
Compositing originated as a solution to enhancing, repairing, and more broadly editing
photographs and video data alike in the film industry as part of the post-production stage.
This is generally thought of as carrying out operations in a 2D domain (a single image
with a known width, height, and colour data). The operations involved are sequential and
entail separating the foreground from the background (matting), or identifying features
from contour (feature matching and segmentation) with the purpose of introducing new
data in the original. Since then, compositing techniques have gained more traction in the
emerging fields of Mixed Reality (MR), Augmented Reality (AR), robotics and machine
vision (scene understanding, scene reconstruction, autonomous navigation). When focusing
on the 3D domain, compositing can be translated into a pipeline 1 - the incipient stage
acquires the scene data, which then undergoes a number of processing steps aimed at
inferring structural properties that ultimately allow for the placement of 3D artefacts
anywhere within the scene, rendering a plausible and consistent result with regard to the
physical properties of the initial input.
This generic approach becomes challenging in the absence of user annotation and
labelling of scene geometry, light sources and their respective magnitude and orientation,
as well as a clear object segmentation and knowledge of surface properties. A single image,
a stereo pair, or even a short image stream may not hold enough information regarding
the shape or illumination of the scene, however, increasing the input data will only incur
an extensive time penalty which is an established challenge in the field.
Recent state-of-the-art methods address the difficulty of inference in the absence of
1In the present document, the term pipeline refers to a software solution formed of stand-alone modules
or stages. It implies that the flow of execution runs in a single direction, and that each module has the
potential to be used on its own as part of other solutions. Moreover, each module is assumed to take an
input set and output data for the following stage, where each module addresses a single type of problem
only.
data, nonetheless, they do not attempt to solve the challenge of compositing artefacts
between existing scene geometry, or cater for the inclusion of new geometry behind complex
surface materials such as translucent glass or in front of reflective surfaces.
The present work focuses on the compositing in the 3D domain and brings forth a
software framework 2 that contributes solutions to a number of challenges encountered in
the field, including the ability to render physically-accurate soft shadows in the absence
of user annotate scene properties or RGB-D data. Another contribution consists in the
timely manner in which the framework achieves a believable result compared to the other
compositing methods which rely on offline rendering. The availability of proprietary
hardware and user expertise are two of the main factors that are not required in order to
achieve a fast and reliable results within the current framework
SynerCrete’18: interdisciplinary approaches for cement-based materials and structural concrete: synergizing expertise and bridging scales of space and time, vol. 2
info:eu-repo/semantics/publishedVersio
Management of bone defects with Bio-oss
Introduction: The defects in the alveolar bone might appear as a result of congenital malformations, traumatic injuries, periodontal disease, surgical traumas, chronic periapical changes and tumors from benign or malignant origin. The aim of this study was to provide solid and healthy area with application of Bio-Oss in the defect.
Materials and methods: Based on the clinical diagnosisestablished by previously taken history, clinical examination and radiographic images oral-surgery interventions was made. To realize the aim of this work, augmentative material was implicated in the bone defects made in the patients after removal of follicular cyst, chronic periapical lesion, and parodontopathia. During the first and seventh day of the interventions, the patients have been followed through from aspect of possible development of local and general complications after the oral-surgery intervention. After period of one, three and six mount control x-ray was made.
Results: Obtained results confirmed that: volume of the socket and defect of the bone was kept, fast revascularization was achieved, bone formation and slow resorption of the augmentative material was achieved, and period of normal healing without infection was also achieved.
Conclusions: The augmentative materials used for treatment of bone defects besides their basic chemical and physical characteristics referring to their solubility in the body fluids, the transformation, modulation and resorption must be completely safe or secure, i.e. not to bring any risk of infection, immunological risk, physiological intolerance or inhibition of the process of restitutio ad integrum. In our study Bio-Oss was confirmed as augmentative material who had this characteristics.
Keywords: bone defect, resorption of the bone, augmentative material, Bio-Os
NASA Tech Briefs, November 1993
Topics covered: Advanced Manufacturing; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences
Advanced Knowledge Application in Practice
The integration and interdependency of the world economy leads towards the creation of a global market that offers more opportunities, but is also more complex and competitive than ever before. Therefore widespread research activity is necessary if one is to remain successful on the market. This book is the result of research and development activities from a number of researchers worldwide, covering concrete fields of research
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