10 research outputs found

    Systematic Approach to IMM Mixing for Unequal Dimension States

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    The interacting multiple model (IMM) estimator outperforms fixed model filters, e.g. the Kalman filter, in scenarios where the targets have periods of disparate behavior. Key to the good performance and low complexity is the mode mixing. Here we propose a systematic approach to mode mixing when the modes have states of different dimensions. The proposed approach is general and encompasses previously suggested solutions. Different mixing approaches are compared, and the proposed methodology is shown to perform very well

    Multiple Model-Based Synchronization Approaches for Time Delayed Slaving Data in a Space Launch Vehicle Tracking System

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    Due to the inherent characteristics of the flight mission of a space launch vehicle (SLV), which is required to fly over very large distances and have very high fault tolerances, in general, SLV tracking systems (TSs) comprise multiple heterogeneous sensors such as radars, GPS, INS, and electrooptical targeting systems installed over widespread areas. To track an SLV without interruption and to hand over the measurement coverage between TSs properly, the mission control system (MCS) transfers slaving data to each TS through mission networks. When serious network delays occur, however, the slaving data from the MCS can lead to the failure of the TS. To address this problem, in this paper, we propose multiple model-based synchronization (MMS) approaches, which take advantage of the multiple motion models of an SLV. Cubic spline extrapolation, prediction through an α-β-γ filter, and a single model Kalman filter are presented as benchmark approaches. We demonstrate the synchronization accuracy and effectiveness of the proposed MMS approaches using the Monte Carlo simulation with the nominal trajectory data of Korea Space Launch Vehicle-I

    An Interacting Multiple Model Approach for Target Intent Estimation at Urban Intersection for Application to Automated Driving Vehicle

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    Research shows that urban intersections are a hotspot for traffic accidents which cause major human injuries. Predicting turning, passing, and stop maneuvers against surrounding vehicles is considered to be fundamental for advanced driver assistance systems (ADAS), or automated driving systems in urban intersections. In order to estimate the target intent in such situations, an interacting multiple model (IMM)-based intersection-target-intent estimation algorithm is proposed. A driver model is developed to represent the driver’s maneuvering on the intersection using an IMM-based target intent classification algorithm. The performance of the intersection-target-intent estimation algorithm is examined through simulation studies. It is demonstrated that the intention of a target vehicle is successfully predicted based on observations at an individual intersection by proposed algorithms. Document type: Articl

    ESTIMATION-BASED SOLUTIONS TO INCOMPLETE INFORMATION PURSUIT-EVASION GAMES

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    Differential games are a useful tool both for modeling conflict between autonomous systems and for synthesizing robust control solutions. The traditional study of games has assumed decision agents possess complete information about one another’s strategies and numerical weights. This dissertation relaxes this assumption. Instead, uncertainty in the opponent’s strategy is treated as a symptom of the inevitable gap between modeling assumptions and applications. By combining nonlinear estimation approaches with problem domain knowledge, procedures are developed for acting under uncertainty using established methods that are suitable for applications on embedded systems. The dissertation begins by using nonlinear estimation to account for parametric uncertainty in an opponent’s strategy. A solution is proposed for engagements in which both players use this approach simultaneously. This method is demonstrated on a numerical example of an orbital pursuit-evasion game, and the findings motivate additional developments. First, the solutions of the governing Riccati differential equations are approximated, using automatic differentiation to obtain high-degree Taylor series approximations. Second, constrained estimation is introduced to prevent estimator failures in near-singular engagements. Numerical conditions for nonsingularity are approximated using Chebyshev polynomial basis functions, and applied as constraints to a state estimate. Third and finally, multiple model estimation is suggested as a practical solution for time-critical engagements in which the form of the opponent’s strategy is uncertain. Deceptive opponent strategies are identified as a candidate approach to use against an adaptive player, and a procedure for designing such strategies is proposed. The new developments are demonstrated in a missile interception pursuit-evasion game in which the evader selects from a set of candidate strategies with unknown weights

    Développement d'une nouvelle algorithmie de localisation adaptée à l'ensemble des mobiles suivis par le système ARGOS

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    Depuis 1978, le système ARGOS assure à l échelle mondiale la collecte de données et la localisation de plateformes pour des applications liées au suivi d animaux, à l océanographie et à la sécurité maritime. La localisation exploite le décalage Doppler affectant la fréquence de porteuse des messages émis par les plateformes et réceptionnés par des satellites dédiés. Au cours des vingt dernières années, les puissances d émission des plateformes se sont réduites pour des conditions d utilisation toujours plus extrêmes, augmentant le nombre de localisations de moindre qualité. Paradoxalement, les utilisateurs ont cherché à identifier des comportements à des échelles de plus en plus petites. L objectif de ce projet est de développer un algorithme de localisation plus performant dans le contexte actuel afin de remplacer le traitement temps réel historique basé sur un ajustement par moindres carrés. Un service hors ligne, permettant de déterminer des localisations encore plus précises, est proposé dans un second temps.Le problème est reformulé comme l estimation de l état d un système dynamique stochastique, tenant compte d un ensemble de modèles de déplacement admissibles pour les plateformes. La détermination exacte de la loi a posteriori de l état présente alors une complexité exponentiellement croissante avec le temps. Le filtre Interacting Multiple Model (IMM) est devenu l outil standard pour approximer en temps réel la loi a posteriori avec un coût de calcul constant. Pour des applications hors ligne, de nombreuses solutions sous-optimales de lissage multi-modèle ont aussi été proposées. La première contribution méthodologique de ce travail présente l extension du cadre initial de l IMM à un ensemble de modèles hétérogènes, c.-à-d. dont les vecteurs d état sont de tailles et de sémantiques différentes. En outre, nous proposons une nouvelle méthode pour le lissage multi-modèle qui offre une complexité réduite et de meilleures performances que les solutions existantes. L algorithme de localisation ARGOS a été réécrit en y incorporant le filtre IMM en tant que traitement temps réel et le lisseur multi-modèle comme service hors ligne. Une étude, menée sur un panel de 200 plateformes munies d un récepteur GPS utilisé comme vérité terrain, montre que ces stratégies améliorent significativement la précision de localisation quand peu de messages sont reçus. En outre, elles délivrent en moyenne 30% de localisations supplémentaires et permettent de caractériser systématiquement l erreur de positionnementThe ARGOS service was launched in 1978 to serve environmental applications including oceanography, wildlife tracking and maritime safety. The system allows for worldwide positioning and data collection of Platform Terminal Transmitters (PTTs). The positioning is achieved by exploiting the Doppler shift in the carrier frequency of the messages transmitted by the PTTs and recorded by dedicated satellite-borne receivers. Over the last twenty years, the transmission power has decreased significantly and platforms have been used in increasingly harsh environments. This led to deliver a greater number of low quality locations while users sought to identify finer platform behavior. This work first focuses on the implementation of a more efficient location processing to replace the historical real time processing relying on a Least Squares adjustment. Secondly, an offline service to infer locations with even higher accuracy is proposed.The location problem is formulated as the estimation of the state vector of a dynamical system, accounting for a set of admissible movement models of the platform. The exact determination of the state posterior pdf displays a complexity growing exponentially with time. The Interacting Multiple Model (IMM) algorithm has become a standard online approach to derive an approximated solution with a constant computational complexity. For offline applications, many sub-optimal multiple model schemes have also been proposed. Our methodological contributions first focused on extending the framework of the IMM filter so as to handle a bank of models with state vectors of heterogeneous size and meaning. Second, we investigated a new sub-optimal solution for multiple model smoothing which proves to be less computationally expensive and displays markedly better performance than equivalent algorithms. The ARGOS location processing was rewritten to include the IMM filter as real time processing and the IMM smoother as offline service. We eventually analyzed their performances using a large dataset obtained from over 200 mobiles carrying both an ARGOS transmitter and a GPS receiver used as ground truth. The results show that the new approaches significantly improve the positioning accuracy, especially when few messages are received. Moreover, the algorithms deliver 30% more positions and give a systematic estimation of the location errorTOULOUSE-INSA-Bib. electronique (315559905) / SudocSudocFranceF

    Maritime expressions:a corpus based exploration of maritime metaphors

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    This study uses a purpose-built corpus to explore the linguistic legacy of Britain’s maritime history found in the form of hundreds of specialised ‘Maritime Expressions’ (MEs), such as TAKEN ABACK, ANCHOR and ALOOF, that permeate modern English. Selecting just those expressions commencing with ’A’, it analyses 61 MEs in detail and describes the processes by which these technical expressions, from a highly specialised occupational discourse community, have made their way into modern English. The Maritime Text Corpus (MTC) comprises 8.8 million words, encompassing a range of text types and registers, selected to provide a cross-section of ‘maritime’ writing. It is analysed using WordSmith analytical software (Scott, 2010), with the 100 million-word British National Corpus (BNC) as a reference corpus. Using the MTC, a list of keywords of specific salience within the maritime discourse has been compiled and, using frequency data, concordances and collocations, these MEs are described in detail and their use and form in the MTC and the BNC is compared. The study examines the transformation from ME to figurative use in the general discourse, in terms of form and metaphoricity. MEs are classified according to their metaphorical strength and their transference from maritime usage into new registers and domains such as those of business, politics, sports and reportage etc. A revised model of metaphoricity is developed and a new category of figurative expression, the ‘resonator’, is proposed. Additionally, developing the work of Lakov and Johnson, Kovesces and others on Conceptual Metaphor Theory (CMT), a number of Maritime Conceptual Metaphors are identified and their cultural significance is discussed

    Kant in English: An Index

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    Kant in English: An Index / By Daniel Fidel Ferrer. ©Daniel Fidel Ferrer, 2017. Pages 1 to 2675. Includes bibliographical references. Index. 1. Ontology. 2. Metaphysics. 3. Philosophy, German. 4. Thought and thinking. 5. Kant, Immanuel, 1724-1804. 6. Practice (Philosophy). 7. Philosophy and civilization. 8). Kant, Immanuel, 1724-1804 -- Wörterbuch. 9. Kant, Immanuel, 1724-1804 -- Concordances. 10. Kant, Immanuel, 1724-1804 -- 1889-1976 – Indexes. I. Ferrer, Daniel Fidel, 1952-. MOTTO As a famous motto calls us back to Kant, Otto Liebmann’s writes (Kant and His Epigones of 1865): “Also muss auf Kant zurückgegangen werden.” “Therefore, must return to Kant.” Table of Contents 1). Preface and Introduction. 2. Background on Kant’s Philosophy (hermeneutical historical situation). 3). Main Index (pages, 25 to 2676). Preface and Introduction Total words indexed: 58,928; for the 12 volumes that are in the MAIN INDEX are indexed: pages 1 to 7321. This monograph by Daniel Fidel Ferrer is 2676 pages in total. The following is a machine index of 12 volumes written by Immanuel Kant and translated from German into English. Everything is indexed including the text, title pages, preface, notes, editorials, glossary, indexes, biographical notes, and even some typos. No stop words or words removed from this index. There are some German words in the text, bibliographies, and in the glossaries (also included in Main Index). Titles in English of Kant’s writings for this index (pages 1 to 7321). Anthropology, History, and Education [Starts on page 1 Correspondence [Starts on page 313 Critique of Pure Reason [Starts page 971 Critique of the Power of Judgment [Starts on page 1771 Lectures on Logic [Starts on page 2247 Lectures on Metaphysics [Starts on page 2991 Notes and Fragments [Starts on page 3670 Opus Postumum [Starts on page 4374 Practical Philosophy [Starts on page 4741 Religion and Rational Theology [Starts on page 5446 Theoretical Philosophy after 1781 [Starts on page 5990 Theoretical Philosophy, 1755-1770 [Starts on page 6541 Universal Natural History and Theory of the Heavens or An Essay on the Constitution and the Mechanical Origin of the Entire Structure of the Universe Based on Newtonian Principles [Starts on page 7162 The whole single file which includes all of these books ends on page 7321. 12 volumes are pages 1 to 7321. These actual texts of these books by Kant are not include here because of copyright. This is only an index of these 7321 pages by Immanuel Kant. There are some German words in the text and in the glossaries, etc. Searching this Main Index. Please note the German words that start with umlauts are at the end of the index because of machine sorting of the words. Starting with the German word “ße” on page 2674 page of this book (see in Main Index). Use the FIND FUNCTION for all examples of the words or names you are searching. Examples from the Main Index mendacium, 5171, 5329, 5389 mendation, 220 mendax, 2702, 2800 mended, 360 Mendel, 416, 925, 965 Mendelian, 2212 Mendels, 345, 363, 417, 458, 560, 572, 588, 926, 928, 929 MENDELSSOHN, 925 Mendelssohn, 8, 9, 19, 98, 99, 100, 101

    Kant in English: An Index

    Get PDF
    Kant in English: An Index / By Daniel Fidel Ferrer. ©Daniel Fidel Ferrer, 2017. Pages 1 to 2675. Includes bibliographical references. Index. 1. Ontology. 2. Metaphysics. 3. Philosophy, German. 4. Thought and thinking. 5. Kant, Immanuel, 1724-1804. 6. Practice (Philosophy). 7. Philosophy and civilization. 8). Kant, Immanuel, 1724-1804 -- Wörterbuch. 9. Kant, Immanuel, 1724-1804 -- Concordances. 10. Kant, Immanuel, 1724-1804 -- 1889-1976 – Indexes. I. Ferrer, Daniel Fidel, 1952-. MOTTO As a famous motto calls us back to Kant, Otto Liebmann’s writes (Kant and His Epigones of 1865): “Also muss auf Kant zurückgegangen werden.” “Therefore, must return to Kant.” Table of Contents 1). Preface and Introduction. 2. Background on Kant’s Philosophy (hermeneutical historical situation). 3). Main Index (pages, 25 to 2676). Preface and Introduction Total words indexed: 58,928; for the 12 volumes that are in the MAIN INDEX are indexed: pages 1 to 7321. This monograph by Daniel Fidel Ferrer is 2676 pages in total. The following is a machine index of 12 volumes written by Immanuel Kant and translated from German into English. Everything is indexed including the text, title pages, preface, notes, editorials, glossary, indexes, biographical notes, and even some typos. No stop words or words removed from this index. There are some German words in the text, bibliographies, and in the glossaries (also included in Main Index). Titles in English of Kant’s writings for this index (pages 1 to 7321). Anthropology, History, and Education [Starts on page 1 Correspondence [Starts on page 313 Critique of Pure Reason [Starts page 971 Critique of the Power of Judgment [Starts on page 1771 Lectures on Logic [Starts on page 2247 Lectures on Metaphysics [Starts on page 2991 Notes and Fragments [Starts on page 3670 Opus Postumum [Starts on page 4374 Practical Philosophy [Starts on page 4741 Religion and Rational Theology [Starts on page 5446 Theoretical Philosophy after 1781 [Starts on page 5990 Theoretical Philosophy, 1755-1770 [Starts on page 6541 Universal Natural History and Theory of the Heavens or An Essay on the Constitution and the Mechanical Origin of the Entire Structure of the Universe Based on Newtonian Principles [Starts on page 7162 The whole single file which includes all of these books ends on page 7321. 12 volumes are pages 1 to 7321. These actual texts of these books by Kant are not include here because of copyright. This is only an index of these 7321 pages by Immanuel Kant. There are some German words in the text and in the glossaries, etc. Searching this Main Index. Please note the German words that start with umlauts are at the end of the index because of machine sorting of the words. Starting with the German word “ße” on page 2674 page of this book (see in Main Index). Use the FIND FUNCTION for all examples of the words or names you are searching. Examples from the Main Index mendacium, 5171, 5329, 5389 mendation, 220 mendax, 2702, 2800 mended, 360 Mendel, 416, 925, 965 Mendelian, 2212 Mendels, 345, 363, 417, 458, 560, 572, 588, 926, 928, 929 MENDELSSOHN, 925 Mendelssohn, 8, 9, 19, 98, 99, 100, 101
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