As the rapid growth of smart phone technology, people have a lot of digital image information such as digital photos or videos. Both data hiding and data compression are very important technologies in image processing...
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As the rapid growth of smart phone technology, people have a lot of digital image information such as digital photos or videos. Both data hiding and data compression are very important technologies in image processing field. On the overview, it seems that there is no relationship between data hiding and data compression because data hiding mechanisms focus on information security and data compression mechanisms emphasize the compression ratio. However, the more secret data is embedded, the more capacity the stego image increases. Actually, they are closely related. Until now, there are many literatures to discuss the secret data how to be embedded into the media image and keeps the original capacity as soon as possible. In this paper, a reversible data hiding scheme based on EMD data hiding and JPEG (Joint Picture Experts Group) compression technology will be proposed. According to experimental results, the authors can prove that our proposed scheme maintains high embedding capacity, security and good compression ratio.
This paper describes an experiment of integrating three courses at the Brazilian Aeronautics Institute of Technology, within the Electronic and computerengineeringgraduateprogram on the 1st semester of 2011. A smar...
This paper describes an experiment of integrating three courses at the Brazilian Aeronautics Institute of Technology, within the Electronic and computerengineeringgraduateprogram on the 1st semester of 2011. A smart grids system was used as a Problem Based Learning (PBL) strategy together with an agile method and best practices within a project developed on three courses: CE-240 Database Systems Project, CE-245 Information Technologies, and CE-229 Software Testing. Students of these courses had to interact, in order to produce a prototype of a smart grids system, simulating a real project development. At the end, a survey among students has proved that the integration of practical exercises has provided higher levels of understanding and problem solving capabilities, improving students' knowledge. The survey also has shown that communication between students from different courses should be improved. The major findings of this paper were that the integration of the three courses was favorable by 83% of the surveyed students, and most students (73%) have considered that their knowledge was improved. Authors recommend the use of practical exercises, courses integration, and PBL to considerably increase the quality of electronic and computerengineering courses.
This paper introduces a neural fuzzy network approach for evolving system modeling. The approach uses neofuzzy neurons and a neural fuzzy structure monished with an incremental learning algorithm that includes adaptiv...
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This paper introduces a neural fuzzy network approach for evolving system modeling. The approach uses neofuzzy neurons and a neural fuzzy structure monished with an incremental learning algorithm that includes adaptive feature selection. The feature selection mechanism starts considering one or more input variables from a given set of variables, and decides if a new variable should be added, or if an existing variable should be excluded or kept as an input. The decision process uses statistical tests and information about the current model performance. The incremental learning scheme simultaneously selects the input variables and updates the neural network weights. The weights are adjusted using a gradient-based scheme with optimal learning rate. The performance of the models obtained with the neural fuzzy modeling approach is evaluated considering weather temperature forecasting problems. Computational results show that the approach is competitive with alternatives reported in the literature, especially in on-line modeling situations where processing time and learning are critical.
As far as we know, there is not a Node Localization Algorithm (NLA) that presents the same accuracy for all possible scenarios. We believe that a NLA should be able to "interpret" the dynamic information of ...
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As far as we know, there is not a Node Localization Algorithm (NLA) that presents the same accuracy for all possible scenarios. We believe that a NLA should be able to "interpret" the dynamic information of the environment. In this sense, simple NLAs are rather focused and might perform well for specific scenarios and applications. Therefore, information fusion and context awareness seems to be an appropriate approach to address this issue. We propose the Smart Environmental Architecture for Node Localization (SEA-NL), which is composed by two main elements: (i) the Smart Beacon Nodes (SBNs) and (ii) the Logical Position of Nodes (LPN). In (i) the obstruction level indicator is estimated and can improve the estimation of distances among nodes. In (ii) environment information and a one to one relation between a node and an object are used and can also improve location estimation. Via simulation, our architecture was tested indoors and outdoors considering three localization algorithms: the Weighed Centroid Localization (WCL), the Centroid Localization, and the Triangular Centroid Localization. Finally, we present an accuracy comparison among NLAs used in isolated way, and by using the SBNs, the LPN, and the SEA-NL, where our architecture improves WCL up to ~30.88%.
Silicon microcantilevers were coated by pulsed laser deposition with vanadium dioxide (VO2) (monoclinic M1 phase) and V 1-xCrxO2 with x near 0.024 (monoclinic M 2 phase), and their mechanical characteristics were stud...
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Silicon microcantilevers were coated by pulsed laser deposition with vanadium dioxide (VO2) (monoclinic M1 phase) and V 1-xCrxO2 with x near 0.024 (monoclinic M 2 phase), and their mechanical characteristics were studied as a function of temperature through the films' insulator-to-metal transition (IMT). The undoped VO2 films grew with (011)M1 planes parallel to the substrate, while Cr-doped VO2 films grew oriented with (201)M2 and (2 01)M2 planes parallel to the substrate. In both cases, the films transformed reversibly through the IMT to the tetragonal (rutile, R) phase, with film (110)R planes oriented parallel to the substrate. The fundamental resonant frequencies of the cantilevers were measured as the temperature was cycled from ambient temperature, through the IMT, and up to 100 °C. Very high resonant frequency changes were observed through the transition for both types of samples, with increases during heating of over 11 and over 15 for the cantilevers coated with pure and Cr-doped VO2, respectively. From the resonant frequencies measured at room temperature for the bare and coated cantilevers in each case, the effective Young's moduli of the films were determined. The values obtained, assuming bulk densities for the films, are 156 ± 7.5 GPa for VO2 (M1 phase) and 102 ± 3 GPa for Cr-doped VO2 (M2 phase). Strong curvature changes during the transition to the R phase were also observed for cantilevers coated with both types of films, but these were significantly higher in the case for the Cr-doped film. Curvature changes for temperature ranges outside the IMT region were small and attributed to differential thermal expansion between film and silicon substrate. From measured cantilever tip displacements in this post-transition range-for the undoped VO 2-coated microcantilevers-a rough estimate of 110 GPa was obtained for the effective Young's modulus for R-phase VO2. The substantially higher changes in resonant frequency and curvature for V1-xCr xO2-coated cant
The internet security problems are a crucial threat to all users in the cyber world. One of the important problems about internet security concerned with user classification and authentication. However, there are mult...
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We estimate the amount of free electrons generated by concealed radioactive materials using MCNP code. This simulation results show that the existence of radioactive sources enhances the number of photons and backgrou...
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We estimate the amount of free electrons generated by concealed radioactive materials using MCNP code. This simulation results show that the existence of radioactive sources enhances the number of photons and background free electrons. Those quantities are influenced by density and thickness of container material.
This paper presents a pioneering approach for weld bead detection in radiographic images obtained by the Double Wall Double Image (DWDI) technique. Such task constitutes an essential step for several high level proces...
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ISBN:
(纸本)9781467315104
This paper presents a pioneering approach for weld bead detection in radiographic images obtained by the Double Wall Double Image (DWDI) technique. Such task constitutes an essential step for several high level processes, such as fully automatic flaw identification on welded joints. Sets of sample pixels, corresponding to candidate solutions provided by a genetic algorithm (GA), are compared to pre-defined synthetic weld bead and pipe models in an image matching procedure. The fitness of each set (individual) is evaluated based on a linear combination of its genotype (evaluated by a heuristic function) and phenotype. The evolutionary process automatically selects the best individual in the population and, thus, provides information such as position, orientation and dimension of the detected object. The proposed approach successfully detects pipes and weld beads in radiographic images of different complexities, encouraging future works.
In this study, we focused on the interoperability and authentication of medical devices in the context of telemedical systems. A recent standard called the ISO/IEEE 11073 Personal Health Device (X73-PHD) Standards add...
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ISBN:
(纸本)9781424441198
In this study, we focused on the interoperability and authentication of medical devices in the context of telemedical systems. A recent standard called the ISO/IEEE 11073 Personal Health Device (X73-PHD) Standards addresses the device interoperability problem by defining common protocols for agent (medical device) and manager (appliance) interface. The X73-PHD standard however has not addressed security and authentication of medical devices which is important in establishing integrity of a telemedical system. We have designed and implemented a security policy within the X73-PHD standards. The policy will enable device authentication using Asymmetric-Key Cryptography and the RSA algorithm as the digital signature scheme. We used two approaches for performing the digital signatures: direct software implementation and use of embedded security modules (ESM). The two approaches were evaluated and compared in terms of execution time and memory requirement. For the standard 2048-bit RSA, ESM calculates digital signatures only 12% of the total time for the direct implementation. Moreover, analysis shows that ESM offers more security advantage such as secure storage of keys compared to using direct implementation. Interoperability with other systems was verified by testing the system with LNI Healthlink, a manager software that implements the X73-PHD standard. Lastly, security analysis was done and the system's response to common attacks on authentication systems was analyzed and several measures were implemented to protect the system against them.
This paper proposes a use of an ordinal classifier to evaluate the financial solidity of non-life insurance companies as strong, moderate, weak, and insolvency. This study constructed an efficient classification model...
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