969 resultados para Optical character recognition


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Methods for optical motion capture often require timeconsuming manual processing before the data can be used for subsequent tasks such as retargeting or character animation. These processing steps restrict the applicability of motion capturing especially for dynamic VR-environments with real time requirements. To solve these problems, we present two additional, fast and automatic processing stages based on our motion capture pipeline presented in [HSK05]. A normalization step aligns the recorded coordinate systems with the skeleton structure to yield a common and intuitive data basis across different recording sessions. A second step computes a parameterization based on automatically extracted main movement axes to generate a compact motion description. Our method does not restrict the placement of marker bodies nor the recording setup, and only requires a short calibration phase.

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Any image processing object detection algorithm somehow tries to integrate the object light (Recognition Step) and applies statistical criteria to distinguish objects of interest from other objects or from pure background (Decision Step). There are various possibilities how these two basic steps can be realized, as can be seen in the different proposed detection methods in the literature. An ideal detection algorithm should provide high recognition sensitiv ity with high decision accuracy and require a reasonable computation effort . In reality, a gain in sensitivity is usually only possible with a loss in decision accuracy and with a higher computational effort. So, automatic detection of faint streaks is still a challenge. This paper presents a detection algorithm using spatial filters simulating the geometrical form of possible streaks on a CCD image. This is realized by image convolution. The goal of this method is to generate a more or less perfect match between a streak and a filter by varying the length and orientation of the filters. The convolution answers are accepted or rejected according to an overall threshold given by the ackground statistics. This approach yields as a first result a huge amount of accepted answers due to filters partially covering streaks or remaining stars. To avoid this, a set of additional acceptance criteria has been included in the detection method. All criteria parameters are justified by background and streak statistics and they affect the detection sensitivity only marginally. Tests on images containing simulated streaks and on real images containing satellite streaks show a very promising sensitivity, reliability and running speed for this detection method. Since all method parameters are based on statistics, the true alarm, as well as the false alarm probability, are well controllable. Moreover, the proposed method does not pose any extraordinary demands on the computer hardware and on the image acquisition process.

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The cadmium thioindate spinel CdIn2S4 semiconductor has potential applications for optoelectronic devices. We present a theoretical study of the structural and optoelectronic properties of the host and of the Cr-doped ternary spinel. For the host spinel, we analyze the direct or indirect character of the energy bandgap, the change of the energy bandgap with the anion displacement parameter and with the site cation distribution, and the optical properties. The main effect of the Cr doping is the creation of an intermediate band within the energy bandgap. The character and the occupation of this band are analyzed for two substitutions: Cr by In and Cr by Cd. This band permits more channels for the photon absorption. The optical properties are obtained and analyzed. The absorption coefficients are decomposed into contributions from the different absorption channels and from the inter-and intra-atomic components.

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The influence of the environment on the optical properties of self-assembled In0.5Ga0.5As surface quantum dots is studied as a function of different ambient conditions for sensing applications. Their room temperature photoluminescence (PL) quenches under vacuum and decreases strongly under dry O2 or N2 environments. Nevertheless, they have a strong signal at 1.55 lm in air or in a wet atmosphere. The presence of water molecules in the environment improves the PL intensity likely due to its polar character and therefore its easier adsorption by the surface dangling bonds, leading to a suppression of the non-radiative recombination centers.

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Optical logic cells, employed in several tasks as optical computing or optically controlled switches for photonic switching, offer a very particular behavior when the working conditions are slightly modified. One of the more striking changes occurs when some delayed feedback is applied between one of the possible output gates and a control input. Some of these new phenomena have been studied by us and reported in previous papers. A chaotic behavior is one of the more characteristic results and its possible applications range from communications to cryptography. But the main problem related with this behavior is the binary character of the resulting signal. Most of the nowadays-employed techniques to analyze chaotic signals concern to analogue signals where algebraic equations are possible to obtain. There are no specific tools to study digital chaotic signals. Some methods have been proposed. One of the more used is equivalent to the phase diagram in analogue chaos. The binary signal is converted to hexadecimal and then analyzed. We represented the fractal characteristics of the signal. It has the characteristics of a strange attractor and gives more information than the obtained from previous methods. A phase diagram, as the one obtained by previous techniques, may fully cover its surface with the trajectories and almost no information may be obtained from it. Now, this new method offers the evolution around just a certain area being this lines the strange attractor.

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In this communication we report a direct immunoassay for detecting dengue virus by means of a label-free interferometric optical detection method. We also demonstrate how we can optimize this sensing response by adding a blocking step able to significantly enhance the optical sensing response. The blocking reagent used for this optimization is a dry milk diluted in phosphate buffered saline. The recognition curve of dengue virus over the proposed surface sensor demonstrates the capacity of this method to be applied in Point of Care technology.

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In this paper, we present a new scheme for off-line recognition of multi-font numerals using the Takagi-Sugeno (TS) model. In this scheme, the binary image of a character is partitioned into a fixed number of sub-images called boxes. The features consist of normalized vector distances (gamma) from each box. Each feature extracted from different fonts gives rise to a fuzzy set. However, when we have a small number of fonts as in the case of multi-font numerals, the choice of a proper fuzzification function is crucial. Hence, we have devised a new fuzzification function involving parameters, which take account of the variations in the fuzzy sets. The new fuzzification function is employed in the TS model for the recognition of multi-font numerals.

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DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT This thesis describes a detailed study of advanced optical fibre sensors based on fibre Bragg grating (FBG), tilted fibre Bragg grating (TFBG) and long-period grating (LPG) and their applications in optical communications and sensing. The major contributions presented in this thesis are summarised below.The most important contribution from the research work presented in this thesis is the implementation of in-fibre grating based refractive index (RI) sensors, which could be the good candidates for optical biochemical sensing. Several fibre grating based RI sensors have been proposed and demonstrated by exploring novel grating structures and different fibre types, and employing efficient hydrofluoric acid etching technique to enhance the RI sensitivity. All the RI devices discussed in this thesis have been used to measure the concentration of sugar solution to simulate the chemical sensing. Efforts have also been made to overcome the RI-temperature cross-sensitivity for practical application. The demonstrated in-fibre grating based RI sensors could be further implemented as potential optical biosensors by applying bioactive coatings to realise high bio-sensitivity and bio-selectivity.Another major contribution of this thesis is the application of TFBGs. A prototype interrogation system by the use of TFBG with CCD-array was implemented to perform wavelength division multiplexing (WDM) interrogation around 800nm wavelength region with the advantages of compact size, fast detection speed and low-cost. As a high light, a novel in-fibre twist sensors utilising strong polarisation dependant coupling behaviour of an 81°-TFBG was presented to demonstrate the high torsion sensitivity and capability of direction recognition.

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The use of amplitude-modulated phase-shift-keyed (AM-PSK) optical data transmission is investigated in a sequence of concatenated links in a wavelength-division-multiplexed clockwork-routed network. The narrower channel spacing made possible by using AM-PSK format allows the network to contain a greater number of network nodes. Full differential precoding at the packet source reduces the amount of high-speed electronics required in the network and also offers simplified header recognition and time-to-live mechanisms.

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In this paper, a new method for offline handwriting recognition is presented. A robust algorithm for handwriting segmentation has been described here with the help of which individual characters can be segmented from a word selected from a paragraph of handwritten text image which is given as input to the module. Then each of the segmented characters are converted into column vectors of 625 values that are later fed into the advanced neural network setup that has been designed in the form of text files. The networks has been designed with quadruple layered neural network with 625 input and 26 output neurons each corresponding to a character from a-z, the outputs of all the four networks is fed into the genetic algorithm which has been developed using the concepts of correlation, with the help of this the overall network is optimized with the help of genetic algorithm thus providing us with recognized outputs with great efficiency of 71%.

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The evaluation from experimental data, of physical quantities, which enter into the electromagnetic Maxwell equations, is described as inverse optical problem. The functional relations between the dependent and independent variables are of transcendental character and numeric procedures for evaluation of the unknowns are largely used. Herein, we discuss a direct approach to the solution, illustrated by a specific example of determination of thin films optical constants from spectrophotometric data. New algorithm is proposed for the parameters evaluation, which does not need an initial guess of the unknowns and does not use iterative procedures. Thus we overcome the intrinsic deficiency of minimization techniques, such as gradient search methods, Simplex methods, etc. The price of it is a need of more computing power, but our algorithm is easily implemented in structures such as grid clusters. We show the advantages of this approach and its potential for generalization to other inverse optical problems.

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Character education has been viewed by many educators as having significant historical, academic, and social value. Many stakeholders in education argue for character development as a curricular experience. While understanding the degree to which character education is of worth to stakeholders of institutions is important, understanding students, teachers, and administrators perspectives from their lived experiences is likewise significant. The purpose of this phenomenological study was to gain a deeper understanding of character education within a Biblical framework environment by examining the lived experiences of students, administrators, and teachers of a Seventh-day Adventist School. Phenomenology describes individuals' daily experiences of phenomena, the manner in which these experiences are structured, and focuses analysis on the perspectives of the persons having the experience (Moustakas, 1994). This inquiry was undertaken to answer the question: What are the perceptions of students, teachers, and an administrator toward character education in a Seventh-day Adventist school setting? Ten participants (seven students and three adults) formed the homogeneous purposive sample, and the major data collection tool was semi-structured interviews (Patton, 1990; Seidman, 2006). Three 90-minute open-ended interviews were conducted with each of the participants. Data analysis included a three-phase process of description, reduction and interpretation. The findings from this study revealed that participants perceived that their involvement in the school's character education program decreased the tendency to violence, improved their conduct and ethical sensibility, enhanced their ability to engage in decision-making concerning social relationships and their impact on others, brought to their attention the emerging global awareness of moral deficiency, and fostered incremental progress from practice and recognition of vices to their acquisition of virtues. The findings, therefore, provide a model for teaching character education from a Seventh-day Adventist perspective. The model is also relevant for non-Seventh day Adventists who aspire to teach character education as a means to improving social and moral conditions in schools.

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This thesis investigates the crossover from and intersection between tangible and intangible heritage in the context of World Heritage. Since the start of the twenty-first century, intangible heritage has become increasingly important in international cultural heritage conservation theory and practice. In heritage literature, intangible heritage has been theorized in relation to tangible or built heritage, thereby extending the definition of cultural heritage to consider a holistic perspective. New heritage conservation instruments have been created for the protection of intangible heritage, such as most prominently the 2003 UNESCO Convention for the Safeguarding of the Intangible Cultural Heritage. The changing conception of cultural heritage that goes beyond tangible heritage has also influenced existing instruments like the 1972 UNESCO Convention concerning the protection of the World Cultural and Natural Heritage. The thesis studies how intangible heritage has been recognized and interpreted in implementing the concept of cultural heritage as defined by the World Heritage Convention. It examines the historical development of the concept of World Cultural Heritage with the aim of tracing the construction of intangible heritage in this context. The thesis consists of six chapters. The introduction sets out the research problem and research question. In the literature review, international cultural heritage conservation is portrayed as the research context, the knowledge gap between World Heritage and intangible heritage is identified and an understanding of the research problem deepened, and methods from similar research in the subject area are presented. The methodology in the third chapter describes choices made concerning the research paradigm, research approach and strategy, the use of concepts and illustrative examples, as well as data collection and analysis methods. Knowledge is constructed using primarily a historical approach and related methods. Through the analysis of pertinent documents and heritage discourses, an understanding of the concept of intangible heritage is developed and the concept of World Cultural Heritage is investigated. In the fourth chapter, intangible heritage is studied by looking at specific cultural heritage discourses, that is, a scientific, a UNESCO, and an ICOMOS discourse. Intangible heritage is theorized in relation to the concepts of tangible heritage, heritage value, and cultural heritage. Knowledge gained in this chapter serves as a theoretical lens to trace the recognition of and tease out interpretations of intangible heritage in the context of implementing the concept of World Cultural Heritage. The results are presented in chapter five. A historical development is portrayed in five time periods and for the concepts of cultural heritage, Outstanding Universal Value, the criteria to assess World Heritage value, and authenticity. The conclusion summarizes the main outcomes, assesses the thesis’ contribution to scientific knowledge as well as its limitations, and outlines possible further research. The main results include the identification of the term intangible heritage as an indicator for a paradigm shift and a new approach to conceiving cultural heritage in international cultural heritage conservation. By focusing on processes and the living relationship between people and their environment or place, intangible heritage emphasizes the anthropological. In the context of this conception, intangible heritage takes on two meanings. First, value is attributed by people and hence, is inherently immaterial. Secondly, place is constituted of a tangible-intangible continuum in terms of attributes. A paradigm shift and increasing recognition of an anthropological approach to cultural heritage were identified for all discourses, that is, UNESCO, ICOMOS, the scientific field, and World Heritage. For World Heritage, intangible heritage was recognized indirectly in terms of historical associations during the 1970s and 1980s. The anthropological shift occurred in the early 1990s. The term intangible was introduced and the meaning of intangible heritage was extended to include cultural associations. The subsequent decade is characterized by a process of internalization and implementation of the new approach to cultural heritage. The 2003 Intangible Cultural Heritage Convention created momentum. By the early 2010s, while not explicitly recognizing the immaterial character of values, a holistic approach to cultural heritage was fully endorsed that considers the idea of intangible attributes as carriers of values. An understanding of the recognition of intangible heritage through the implementation of the World Heritage Convention and scientific research in general provide an important knowledge base for implementing the Convention in a more coherent, objective, and well-informed way.

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This thesis investigates the crossover from and intersection between tangible and intangible heritage in the context of World Heritage. Since the start of the twenty-first century, intangible heritage has become increasingly important in international cultural heritage conservation theory and practice. In heritage literature, intangible heritage has been theorized in relation to tangible or built heritage, thereby extending the definition of cultural heritage to consider a holistic perspective. New heritage conservation instruments have been created for the protection of intangible heritage, such as most prominently the 2003 UNESCO Convention for the Safeguarding of the Intangible Cultural Heritage. The changing conception of cultural heritage that goes beyond tangible heritage has also influenced existing instruments like the 1972 UNESCO Convention concerning the protection of the World Cultural and Natural Heritage. The thesis studies how intangible heritage has been recognized and interpreted in implementing the concept of cultural heritage as defined by the World Heritage Convention. It examines the historical development of the concept of World Cultural Heritage with the aim of tracing the construction of intangible heritage in this context. The thesis consists of six chapters. The introduction sets out the research problem and research question. In the literature review, international cultural heritage conservation is portrayed as the research context, the knowledge gap between World Heritage and intangible heritage is identified and an understanding of the research problem deepened, and methods from similar research in the subject area are presented. The methodology in the third chapter describes choices made concerning the research paradigm, research approach and strategy, the use of concepts and illustrative examples, as well as data collection and analysis methods. Knowledge is constructed using primarily a historical approach and related methods. Through the analysis of pertinent documents and heritage discourses, an understanding of the concept of intangible heritage is developed and the concept of World Cultural Heritage is investigated. In the fourth chapter, intangible heritage is studied by looking at specific cultural heritage discourses, that is, a scientific, a UNESCO, and an ICOMOS discourse. Intangible heritage is theorized in relation to the concepts of tangible heritage, heritage value, and cultural heritage. Knowledge gained in this chapter serves as a theoretical lens to trace the recognition of and tease out interpretations of intangible heritage in the context of implementing the concept of World Cultural Heritage. The results are presented in chapter five. A historical development is portrayed in five time periods and for the concepts of cultural heritage, Outstanding Universal Value, the criteria to assess World Heritage value, and authenticity. The conclusion summarizes the main outcomes, assesses the thesis’ contribution to scientific knowledge as well as its limitations, and outlines possible further research. The main results include the identification of the term intangible heritage as an indicator for a paradigm shift and a new approach to conceiving cultural heritage in international cultural heritage conservation. By focusing on processes and the living relationship between people and their environment or place, intangible heritage emphasizes the anthropological. In the context of this conception, intangible heritage takes on two meanings. First, value is attributed by people and hence, is inherently immaterial. Secondly, place is constituted of a tangible-intangible continuum in terms of attributes. A paradigm shift and increasing recognition of an anthropological approach to cultural heritage were identified for all discourses, that is, UNESCO, ICOMOS, the scientific field, and World Heritage. For World Heritage, intangible heritage was recognized indirectly in terms of historical associations during the 1970s and 1980s. The anthropological shift occurred in the early 1990s. The term intangible was introduced and the meaning of intangible heritage was extended to include cultural associations. The subsequent decade is characterized by a process of internalization and implementation of the new approach to cultural heritage. The 2003 Intangible Cultural Heritage Convention created momentum. By the early 2010s, while not explicitly recognizing the immaterial character of values, a holistic approach to cultural heritage was fully endorsed that considers the idea of intangible attributes as carriers of values. An understanding of the recognition of intangible heritage through the implementation of the World Heritage Convention and scientific research in general provide an important knowledge base for implementing the Convention in a more coherent, objective, and well-informed way.

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The purpose of this article is to examine the factors that affect the inclusion of pupils in programmes for children with special needs from the perspective of the theory of recognition. The concept of recognition, which includes three aspects of social justice (economic, cultural and political), argues that the institutional arrangements that prevent ‘parity of participation’ in the school social life of the children with special needs are affected not only by economic distribution but also by the patterns of cultural values. A review of the literature shows that the arrangements of education of children with special needs are influenced primarily by the patterns of cultural values of capability and inferiority, as well as stereotypical images of children with special needs. Due to the significant emphasis on learning skills for academic knowledge and grades, less attention is dedicated to factors of recognition and representational character, making it impossible to improve some meaningful elements of inclusion. Any participation of pupils in activities, the voices of the children, visibility of the children due to achievements and the problems of arbitrariness in determining boundaries between programmes are some such elements. Moreover, aided by theories, the actions that could contribute to better inclusion are reviewed. An effective approach to changes would be the creation of transformative conditions for the recognition and balancing of redistribution, recognition, and representation. (DIPF/Orig.)