Search results for "image processing"
showing 10 items of 3285 documents
Demultiplexing Visible and Near-Infrared Information in Single-Sensor Multispectral Imaging
2016
In this paper, we study a single-sensor imaging system that uses a multispectral filter array to spectrally sample the scene. Our system captures information in both visible and near-infrared bands of the electromagnetic spectrum. Due to manufacturing limitations, the visible filters in this system also transmit the NIR radiation. Similarly, visible light is transmitted by the NIR filter, leading to inaccurate mixed spectral measurements. We present an algorithm that resolves this issue by separating NIR and visible information. Our method achieves this goal by exploiting the correlation of multispectral images in both spatial and spectral domains. Simulation results show that the mean squa…
Accelerating Application Migration in HPC
2016
It is predicted that the number of cores per node will rapidly increase with the upcoming era of exascale supercomputers. As a result, multiple applications will have to share one node and compete for the (often scarce) resources available on this node. Furthermore, the growing number of hardware components causes a decrease in the mean time between failures. Application migration between nodes has been proposed as a tool to mitigate these two problems: Bottlenecks due to resource sharing can be addressed by load balancing schemes which migrate applications; and hardware errors can often be tolerated by the system if faulty nodes are detected and processes are migrated ahead of time.
A survey of serendipity in recommender systems
2016
We summarize most efforts on serendipity in recommender systems.We compare definitions of serendipity in recommender systems.We classify the state-of-the-art serendipity-oriented recommendation algorithms.We review methods to assess serendipity in recommender systems.We provide the future directions of serendipity in recommender systems. Recommender systems use past behaviors of users to suggest items. Most tend to offer items similar to the items that a target user has indicated as interesting. As a result, users become bored with obvious suggestions that they might have already discovered. To improve user satisfaction, recommender systems should offer serendipitous suggestions: items not …
A Survey on how to Cross-Reference Web Information Sources
2015
International audience; The goal of giving information a well-defined meaning is currently shared by different research communities. Once information has a well-defined meaning, it can be searched and retrieved more effectively. Therefore, this paper is a survey about the methods that compare different textual information sources in order to determine whether they address a similar information or not. The improvement of the studied methods will eventually lead to increase the efficiency of documentary research. In order to achieve this goal, the first category of methods focuses on semantic measure definitions. A second category of methods focuses on paraphrase identification techniques, an…
New, fast, and accurate procedure to calibrate a 2-dimensional digital measurement method.
2005
Traditionally, dental casts have been measured by hand, with conventional calipers. Today, several digital methods are available for automatically measuring tooth size, but their accuracy depends on proper calibration. The purpose of this article is to introduce a fast and accurate procedure to calibrate a previously introduced 2-dimensional computerized system of measuring mesiodistal tooth size and calculating overall and anterior Bolton ratios. In this calibration method, the cast is digitized while sitting on a sheet of graph paper. The magnification of the paper in 2 axes can be easily calculated and hence the magnification of the dental cast digital image.
Modeling urban growth by cellular automata
1996
International audience; The structural development of human settlements can be characterized as a complex highly feedbacketed process. The assumption that this process is governed by rather few fundamental laws stimulated a considerable research in the field of urban growth during the last decade. Aiming at the comprehension of the basic underlying dynamics different approaches from the field of self-organizing systems have been proposed. In this paper we present a "cellular model" of urban growth dynamics based on the work of White, Engelen and Uljee. As a starting point this model throws some light on the mechanism of urban growth. But even more important, it raises a lot of questions con…
A two-layer security model for accessing multimedia content in social networks
2016
La seguridad de un sitio web es hoy en día una de las principales preocupaciones de los administradores de sistemas. La seguridad es también el reto más importante al que se enfrentan los desarrolladores web a la hora de diseñar una plataforma fiable que ofrezca servicios a los usuarios públicos. Es bien sabido que el contenido multimedia en la web está en continuo crecimiento y, recientemente, este tipo de medios se utiliza cada vez más en las redes sociales. El acceso a los contenidos multimedia en el contexto de las redes sociales debe ser fácil y seguro. En este artículo se presenta un modelo de seguridad con capacidad semántica para el acceso a contenidos multimedia en las redes social…
Optical Flow with Theoretically Justified Warping Applied to Medical Imaging
2015
International audience; Motion induced artifacts represent a major obstacle in the correct malignant lesion detection in medical imaging especially in MRI. The goal of this paper is to evaluate the performance of a new non-rigid motion correction algorithm based on the optical flow method. The proposed algorithm specifically addresses three major problems in MRI: the induced gaps in 3D images, the constancy assumption of current optical flow algorithms and the existence of large non-linear movement. In this paper, we compare the performance of extracted kinetic features from the tumor regions under consideration of several 2-D or 3-D motion compensation parameters for the differential diagn…
Teachers’ Readiness for Remote Teaching During COVID-19 Pandemic: The Case of Latvia
2021
The state of emergency due to the COVID-19 pandemic influenced educational processes in schools all over the world. Teachers had a very short time to reform all their work and started to use new technologies, which increased their workload and level of stress. Information on factors affecting teachers’ readiness for remote teaching is insufficient, and we aimed to investigate it in this study. We performed a population-based cross-sectional study after the first experience of teachers working remotely during the Spring 2020 state of emergency in Latvia. We assessed the self-reported “overall readiness for remote teaching” using five sub-domains of a specific survey. We observed a reversed a…
A Digital Watermarking Algorithm Based on DCT: Application on Medical Image
2012
International audience; This work is a presentation of a new approach of robust watermarking applied in medical domain such as telemedicine hence the need to keep the visual aspect of medical images and other conservation of the various data substituted. For hiding information, the proposed method uses the Discrete Cosine Transform (DCT) space. To control identification and eventually the correction (if possible) of the data inserted, it should be noted that we used the series turbocode to recover the data inserted and after application of several attacks.