WTLS-Bayes Filter-based Relative Pose Estimation for Space Non-cooperative Unknown Target Without a Priori Knowledge

Abstract The relative pose estimation of a space noncooperative target is an attractive yet challenging task due to the complexity of the target background and illumination, and the lack of a priori knowledge. Unfortunately, these negative factors have a grave impact on the estimation accuracy and the robustness of filter algorithms. In response, this paper proposes a novel filter algorithm to estimate the relative pose to improve the robustness based on a stereovision system. First, to obtain a coarse relative pose, the weighted total least squares (WTLS) algorithm is adopted to estimate the relative pose based on several feature points. The resulting relative pose is fed into the subsequent filter scheme as observation quantities. Second, the classic Bayes filter is exploited to estimate the relative state except for moment-of-inertia ratios. Additionally, the one-step prediction results are used as feedback for WTLS initialization. The proposed algorithm successfully eliminates the dependency on continuous tracking of several fixed points. Finally, comparison experiments demonstrate that the proposed algorithm presents a better performance in terms of robustness and convergence time.

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Language and Idealism

Academicus International Scientific Journal ◽

10.7336/academicus.2021.23.10 ◽

2021 ◽

Vol 23 ◽

pp. 156-177

Author(s):

Marsonet Michele

Keyword(s):

Immanuel Kant ◽

A Priori ◽

Ordinary Language ◽

Point Of View ◽

A Priori Knowledge ◽

Scientific Language ◽

Philosophical Inquiry ◽

Analytic Tradition ◽

The One ◽

Priori Knowledge

In the philosophical inquiry adopted by logical empiricists, analysis of scientific language becomes something similar to a metaphysical endeavor which is meant to establish the bounds of sense, and this stance may be easily traced back to Wittgenstein’s Tractatus Logico-Philosophicus. On the other hand, the analytic tradition transferred this conception to the analysis of ordinary language, and this move, eventually, was able to restore the confidence of many philosophers in their own work. After all they were doing something important and worthwhile, that is to say, something no one else was doing, since linguists are certainly concerned with language, but from quite a different point of view. At this point we may well ask ourselves: What is wrong with this kind of approach, given the present crisis of the analytic tradition and the growing success of the so-called postanalytic thought? At first sight it looks perfectly legitimate and, moreover, it produced important results, as anybody can verify just reading the masterpieces of contemporary analytic philosophy. To answer the question: What is wrong?, we must first of all take into account language itself and check what it is meant to be within the analytic tradition. This will give our question a clear answer. We have to verify, furthermore, what kind of knowledge philosophy needs to be equipped with if it wants to preserve its autonomy. The logical positivists clearly claimed in their program that there is no synthetic a priori knowledge such as the one envisioned by Immanuel Kant. There is, however, an analytic and a priori knowledge which is supplied by mathematics and logic alone. Within this field, the techniques of contemporary formal logic are exalted because they allow us to build artificial languages which - at least theoretically - eliminate the ambiguities of everyday speech.

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Joint Estimation of Doppler Stretch and Time Delay of Wideband Echoes for LFM Pulse Radar Based on Sigmoid-FRFT Transform under the Impulsive Noise Environment

Electronics ◽

10.3390/electronics8020121 ◽

2019 ◽

Vol 8 (2) ◽

pp. 121 ◽

Cited By ~ 2

Author(s):

Li Li ◽

Nicolas Younan ◽

Xiaofei Shi

Keyword(s):

Fourier Transform ◽

Time Delay ◽

Fractional Fourier Transform ◽

Impulsive Noise ◽

A Priori ◽

Joint Estimation ◽

Estimation Accuracy ◽

A Priori Knowledge ◽

Noise Interference ◽

Priori Knowledge

To overcome the limitation of performance degradation of existing methods based on fractional Fourier transform in impulsive noise, and fractional lower-order statistics based method dependence on a priori knowledge of the noise, a novel Sigmoid fractional Fourier transform (Sigmoid-FRFT) is presented in this paper. This novel approach is then used to estimate the Doppler stretch and time delay. Furthermore, the properties of the Sigmoid transform, robustness and boundedness of the Sigmoid-FRFT to the S α S noise, and the computation complexity of the Sigmoid-FRFT method are presented to evaluate the performance of the proposed method. Simulation results and theoretical analysis are presented to demonstrate the applicability of the forgoing method. It is shown that the proposed method not only can effectively suppress impulsive noise interference but also does not need a priori knowledge of the noise, with higher estimation accuracy and lower computational complexity in impulsive noise environments.

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Transformations of Transcendental Philosophy: Wolff, Kant, and Hegel

Hegel Bulletin ◽

10.1017/s0263523200000161 ◽

2011 ◽

Vol 32 (1-2) ◽

pp. 50-79 ◽

Cited By ~ 3

Author(s):

Karin de Boer

Keyword(s):

A Priori ◽

Transcendental Philosophy ◽

A Priori Knowledge ◽

Pure Reason ◽

Empirical Knowledge ◽

Critique Of Pure Reason ◽

Common View ◽

Synthetic A Priori ◽

The One ◽

Priori Knowledge

Kant's philosophy is generally known as transcendental philosophy or transcendental idealism, terms often thought to describe the inquiry into the subjective conditions of empirical knowledge carried out in theCritique of Pure Reason. On this conception of transcendental philosophy Kant is seen to pursue a project very different from both Wolffian metaphysics and Hegelian speculative science. This view is confirmed by scholars who compare Kant's conception of transcendental philosophy to the Scholastics' conception of ‘transcendentals’ such as unity, truth, and perfection. On their account, there remains a puzzling gap between, on the one hand, the scholastic conception of the most general determinations of all beings and, on the other hand, Kant's investigation into the conditions of possibility of experience.In this article I want to challenge this common view of Kant's transcendental philosophy for two reasons. The first reason concerns the question of how theCritique of Pure Reasonitself should be read. I take the view that in the firstCritiqueKant's primary aim is to determine the conditions of synthetic a priori knowledge rather than to identify the a priori conditions of empirical knowledge. Since metaphysics was traditionally considered to be the discipline that possessed a priori knowledge of things, this view makes good sense of Kant's presentation of theCritique of Pure Reasonas a work intended to transform metaphysics into a science. In this article I hope to clarify the nature of this transformation by determining the elements which Kant's transcendental philosophy has in common with Wolff's ontology, as well as the respects in which Kant turns against Wolff. I thus hope to solve some of the riddles posed by Kant's use of the term ‘transcendental philosophy’ in theCritique of Pure Reason.

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Seeing, Knowing, and Doing

10.1093/oso/9780197503508.001.0001 ◽

2020 ◽

Author(s):

Robert Audi

Keyword(s):

Practical Reasoning ◽

Practical Knowledge ◽

A Priori ◽

Human Action ◽

A Priori Knowledge ◽

Rational Action ◽

Reasons For Action ◽

Discriminative Response ◽

Rich Information ◽

Priori Knowledge

This book provides an overall theory of perception and an account of knowledge and justification concerning the physical, the abstract, and the normative. It has the rigor appropriate for professionals but explains its main points using concrete examples. It accounts for two important aspects of perception on which philosophers have said too little: its relevance to a priori knowledge—traditionally conceived as independent of perception—and its role in human action. Overall, the book provides a full-scale account of perception, presents a theory of the a priori, and explains how perception guides action. It also clarifies the relation between action and practical reasoning; the notion of rational action; and the relation between propositional and practical knowledge. Part One develops a theory of perception as experiential, representational, and causally connected with its objects: as a discriminative response to those objects, embodying phenomenally distinctive elements; and as yielding rich information that underlies human knowledge. Part Two presents a theory of self-evidence and the a priori. The theory is perceptualist in explicating the apprehension of a priori truths by articulating its parallels to perception. The theory unifies empirical and a priori knowledge by clarifying their reliable connections with their objects—connections many have thought impossible for a priori knowledge as about the abstract. Part Three explores how perception guides action; the relation between knowing how and knowing that; the nature of reasons for action; the role of inference in determining action; and the overall conditions for rational action.

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How Reality is Reasonable

10.1093/oso/9780198810384.003.0006 ◽

2018 ◽

Author(s):

Donald C. Williams

Keyword(s):

A Priori ◽

A Priori Knowledge ◽

Dimensional Manifold ◽

The World ◽

Being There ◽

Ways Of Being ◽

Fundamental Entity ◽

Spatiotemporal Relations ◽

Priori Knowledge

This chapter begins with a systematic presentation of the doctrine of actualism. According to actualism, all that exists is actual, determinate, and of one way of being. There are no possible objects, nor is there any indeterminacy in the world. In addition, there are no ways of being. It is proposed that actual entities stand in three fundamental relations: mereological, spatiotemporal, and resemblance relations. These relations govern the fundamental entities. Each fundamental entity stands in parthood relations, spatiotemporal relations, and resemblance relations to other entities. The resulting picture is one that represents the world as a four-dimensional manifold of actual ‘qualitied contents’—upon which all else supervenes. It is then explained how actualism accounts for classes, quantity, number, causation, laws, a priori knowledge, necessity, and induction.

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How Do We Know that We’re Not Brains in Vats?

10.1093/oso/9780199564477.003.0007 ◽

2018 ◽

Author(s):

Keith DeRose

Keyword(s):

Epistemic Justification ◽

A Priori ◽

A Priori Knowledge ◽

Conservative Approach ◽

Contingent Fact ◽

Brains In Vats ◽

Priori Knowledge

In this chapter the contextualist Moorean account of how we know by ordinary standards that we are not brains in vats (BIVs) utilized in Chapter 1 is developed and defended, and the picture of knowledge and justification that emerges is explained. The account (a) is based on a double-safety picture of knowledge; (b) has it that our knowledge that we’re not BIVs is in an important way a priori; and (c) is knowledge that is easily obtained, without any need for fancy philosophical arguments to the effect that we’re not BIVs; and the account is one that (d) utilizes a conservative approach to epistemic justification. Special attention is devoted to defending the claim that we have a priori knowledge of the deeply contingent fact that we’re not BIVs, and to distinguishing this a prioritist account of this knowledge from the kind of “dogmatist” account prominently championed by James Pryor.

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