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Showing papers on "Representation (systemics) published in 1999"


Journal ArticleDOI
TL;DR: This article will focus on the literature on gamma oscillatory activities in humans and will describe the different types of gamma responses and how to analyze them, as well as convergence evidence that suggests that one particular type of gamma activity (induced gamma activity) is observed during the construction of an object representation.

2,031 citations


Journal ArticleDOI
TL;DR: This article propose an alternative argument for representation that builds on the broader interpretation of rational actor political theory, an interpretation that emphasizes expressive considerations relative to instrumental considerations, and operates in a richer motivational setting.
Abstract: An essential feature of political representation is that a mediating assembly is set between the citizenry and political decision making. Representation involves indirect decision making or agency. Rational actor political theory often assumes representation in order to focus on problems of a principal–agent kind, but offers only relatively weak arguments for representation. We offer an alternative argument for representation that builds on our broader interpretation of rational actor political theory – an interpretation that emphasizes expressive considerations relative to instrumental considerations, and operates in a richer motivational setting. As well as providing an account of representation, we believe that our approach is capable of re-connecting rational actor political theory to many of the concerns of more traditional political theory.

498 citations


Book
01 Jan 1999
TL;DR: In Representation and Recognition in Vision, Shimon Edelman bases a comprehensive approach to visual representation on the notion of correspondence between proximal (internal) and distal similarities in objects and develops a theory of representation that is related to Shepard's notion of second-order isomorphism between representations and their targets.
Abstract: Shimon Edelman bases a comprehensive approach to visual representation on the notion of correspondence between proximal (internal) and distal similarities in objects. Researchers have long sought to understand what the brain does when we see an object, what two people have in common when they see the same object, and what a "seeing" machine would need to have in common with a human visual system. Recent neurobiological and computational advances in the study of vision have now brought us close to answering these and other questions about representation. In Representation and Recognition in Vision, Shimon Edelman bases a comprehensive approach to visual representation on the notion of correspondence between proximal (internal) and distal similarities in objects. This leads to a computationally feasible and formally veridical representation of distal objects that addresses the needs of shape categorization and can be used to derive models of perceived similarity. Edelman first discusses the representational needs of various visual recognition tasks, and surveys current theories of representation in this context. He then develops a theory of representation that is related to Shepard's notion of second-order isomorphism between representations and their targets. Edelman goes beyond Shepard by specifying the conditions under which the representations can be made formally veridical. Edelman assesses his theory's performance in identification and categorization of 3D shapes and examines it in light of psychological and neurobiological data concerning the object-processing stream in primate vision. He also discusses the connections between his theory and other efforts to understand representation in the brain.

400 citations


Journal ArticleDOI
TL;DR: In this article, a model of object shape by nets of medial and boundary primitives is justified as richly capturing multiple aspects of shape and yet requiring representation space and image analysis work proportional to the number of primitives.
Abstract: A model of object shape by nets of medial and boundary primitives is justified as richly capturing multiple aspects of shape and yet requiring representation space and image analysis work proportional to the number of primitives. Metrics are described that compute an object representation's prior probability of local geometry by reflecting variabilities in the net's node and link parameter values, and that compute a likelihood function measuring the degree of match of an image to that object representation. A paradigm for image analysis of deforming such a model to optimize a posteriori probability is described, and this paradigm is shown to be usable as a uniform approach for object definition, object-based registration between images of the same or different imaging modalities, and measurement of shape variation of an abnormal anatomical object, compared with a normal anatomical object. Examples of applications of these methods in radiotherapy, surgery, and psychiatry are given.

354 citations


01 Oct 1999
TL;DR: The purpose in this panel is to focus on some main distinctions which are necessary to analyze the mathematical knowledge from a learning point of view and to explain how many students come up against difficulties at each level of curriculum and very often cannot go beyond.

314 citations



Proceedings ArticleDOI
01 Sep 1999
TL;DR: This representation is intended to provide a generic infrastructure that will facilitate the capture and exchange of function information among researchers at present, and eventually in industry by contributing to interoperability between design systems, be they commercial or developed internally within a company.
Abstract: This paper proposes a standardized representation of function for use by the research community, industry, and eventually commercial software vendors. This includes schemata (information models) for representation of function and associated flows, as well as an initial attempt at developing taxonomies of functions and flows. The objective of the latter effort is to generate taxonomies that are as small as possible, yet generic enough to allow modeling of a broad variety of engineering artifacts. This representation is intended to provide a generic infrastructure that will facilitate the capture and exchange of function information among researchers at present, and eventually in industry by contributing to interoperability between design systems, be they commercial or developed internally within a company.

215 citations


Patent
09 Feb 1999
TL;DR: In this article, the authors proposed a scheme for secure digital representation distribution that combines encryption and watermarking, where a user at a client wants to download a digital representation, and the user makes a request to a server for the digital representation.
Abstract: Techniques for secure distribution of digital representations that combine encryption and watermarking. When a user at a client desires to download a digital representation, the user makes a request to a server for the digital representation, which encrypts the digital representation using a first key and downloads the encrypted digital representation to the user. Before the user performs any operation on the decrypted digital representation, a secret fingerprint watermark identifying the user is added to the digital representation. The fingerprint watermark is added either at the server or at the client and a copy of the fingerprinted digital representation is kept at the server. If the user makes an impermissible use of the digital representation, the secret fingerprint watermark can be used to identify the user. The request made by the user indicates the type of use that the user whished to make of the digital representation. If the use involves storage of the digital representation at the client, the server provides a second key that the client employs to encrypt the digital representation. If the user has permission to do so, the user may modify the digital representation and return the modified digital representation to the server for further distribution. In this case, the second key is used to encrypt the digital representation when it is sent to the server. The second key also serves as the user identification in the fingerprint watermark. If the user loses the second key, it can be recovered from the copy of the fingerprinted digital representation kept at the server. The first and second keys and any decrypted copy of the digital representation are kept in secure storage in the client.

214 citations


Patent
08 Oct 1999
TL;DR: In this article, the authors fit a set of upper and lower teeth in a masticatory system by generating a computer representation of the masticator system and computing an occlusion based on interactions in the computer representation.
Abstract: Methods and apparatus fit a set of upper and lower teeth in a masticatory system by generating a computer representation of the masticatory system and computing an occlusion based on interactions in the computer representation of the masticatory system.

214 citations



Journal ArticleDOI
David P. Tegarden1
TL;DR: This tutorial surveys the issues related to applying visualization technologies to business problem solving and suggests it may be possible to use innate spatial/visual abilities to allow the business decision-maker to separate the “wheat from the chaff.”
Abstract: With the flood of data produced by today’s information systems, something must be done to allow business decision-makers to extract the information the data contains. The recent advances in visualization technologies provide the capability to begin to use human visual/spatial abilities to solve the abstract problems found in business. If business problems can be visualized with an appropriate representation, then it may be possible to use innate spatial/visual abilities to allow the business decision-maker to separate the “wheat from the chaff.” This tutorial surveys the issues related to applying visualization technologies to business problem solving.

Journal Article
TL;DR: In this review, a description is offered of the way actions are represented, how these representations are built, and how their content can be accessed by the agent and by other agents.
Abstract: In this review, a description is offered of the way actions are represented, how these representations are built, and how their content can be accessed by the agent and by other agents. Such a description will appear critical for understanding how an action is attributed to its proper origin, or, in other words, how a subject can make a conscious judgement about who the agent of that action is (an agency judgement). This question is central to the problem of self-consciousness: Action is one of the main channels used for communication between individuals, so that determining the agent of an action contributes to differentiating the self from others.

Patent
06 Dec 1999
TL;DR: In this article, the authors describe a system that processes a user query for information and organizes, analyzes and presents in a graphic representation, the relevant data for the user, allowing the user to immediately and intrinsically infer the existence of relationships and trends that would normally not have been apparent otherwise.
Abstract: The software system described processes a user query for information and organizes, analyzes and presents in a graphic representation, the relevant data for the user, allowing the user to immediately and intrinsically infer the existence of relationships and trends that would normally not have been apparent otherwise. This method supports decision making to an improved level and is capable of presenting data relationships across multiple planes and accessing dissimilar data sets. The ability to then access the underlying data is also disclosed.

Journal ArticleDOI
James H. Elder1
TL;DR: A novel method for inverting the edge code to reconstruct a perceptually accurate estimate of the original image is reported, and thus it is demonstrated that the proposed representation embodies virtually all of the perceptually relevant information contained in a natural image.
Abstract: We address the problem of computing a general-purpose early visual representation that satisfies two criteria. 1) Explicitness: To be more useful than the original pixel array, the representation must take a significant step toward making important image structure explicit. 2) Completeness: To support a diverse set of high-level tasks, the representation must not discard information of potential perceptual relevance. The most prevalent representation in image processing and computer vision that satisfies the completeness criterion is the wavelet code. In this paper, we propose a very different code which represents the location of each edge and the magnitude and blur scale of the underlying intensity change. By making edge structure explicit, we argue that this representation better satisfies the first criterion than do wavelet codes. To address the second criterion, we study the question of how much visual information is lost in the representation. We report a novel method for inverting the edge code to reconstruct a perceptually accurate estimate of the original image, and thus demonstrate that the proposed representation embodies virtually all of the perceptually relevant information contained in a natural image. This result bears on recent claims that edge representations do not contain all of the information needed for higher level tasks.

Journal ArticleDOI
Jo Little1
TL;DR: A review of rural geographers' engagement with some of the themes of cultural geography and the contribution of this involvement to the development of the subject of rural geography can be found in this article.
Abstract: In a recent editorial in the Journal ofRural Studies Cloke (1997) remarked on the buoyant state of rural studies. Identifying major advances in both the quantity and quality of rural research he argues that 'we are now experiencing the most exciting period of rural studies, certainly within the last 20 years' (Cloke, 1997: 371). One of the major breakthroughs identified by Cloke, and now filtering through to published work, is the engagement by rural geographers with the much referenced 'cultural turn'. Major themes from within this cultural perspective, for example the representation and construction of rurality, the marginalization of 'others' and the spatiality of nature (Cloke, 1977) have become an accepted, if not central, part of the writing and teaching of academic rural geography. While an interest in new theoretical/conceptual debates in rural geography is to be welcomed especially given a traditional reluctance to take on other theoretical developments in the subject there is a sense in which the application of the 'cultural turn' has, at times, been simplistic and uncritical. This review provides a timely opportunity for a critique (albeit brief and necessarily selective) of rural geographers' engagement with some of the themes of cultural geography and of the contribution of this involvement to the development of the subject.

Journal ArticleDOI
TL;DR: In this article, the extent and effectiveness of non-union representation is examined and whether they can provide effective substitutes for union-based systems, and it is argued that this appears unlikely.
Abstract: Legislative developments and some renewal of managerial interest are drawing attention to systems of employee representation in the non-union sector. This article examines such data as exist on the extent and effectiveness of such systems, asks whether they can provide effective substitutes for union-based systems, and argues that this appears unlikely.

Journal ArticleDOI
TL;DR: A geometrical representation of McCulloch-Pitts neural model is presented and a clear visual picture and interpretation of the model can be seen and two interesting applications based on the interpretation are discussed.
Abstract: In this paper, a geometrical representation of McCulloch-Pitts neural model (1943) is presented, From the representation, a clear visual picture and interpretation of the model can be seen. Two interesting applications based on the interpretation are discussed. They are 1) a new design principle of feedforward neural networks and 2) a new proof of mapping abilities of three-layer feedforward neural networks.

Journal ArticleDOI
S.F. Frisken-Gibson1
TL;DR: A linked volume representation that enables physically realistic modeling of object interactions such as: collision detection, collision response, 3D object deformation, and interactive object modification by carving, cutting, tearing, and joining is presented.
Abstract: In volume graphics, objects are represented by arrays or clusters of sampled 3D data. A volumetric object representation is necessary in computer modeling whenever interior structure affects an object's behavior or appearance. However, existing volumetric representations are not sufficient for modeling the behaviors expected in applications such as surgical simulation, where interactions between both rigid and deformable objects and the cutting, tearing, and repairing of soft tissues must be modeled in real time. Three-dimensional voxel arrays lack the sense of connectivity needed for complex object deformation, while finite element models and mass-spring systems require substantially reduced geometric resolution for interactivity and they can not be easily cut or carved interactively. This paper discusses a linked volume representation that enables physically realistic modeling of object interactions such as: collision detection, collision response, 3D object deformation, and interactive object modification by carving, cutting, tearing, and joining. The paper presents a set of algorithms that allow interactive manipulation of linked volumes that have more than an order of magnitude more elements and considerably more flexibility than existing methods. Implementation details, results from timing tests, and measurements of material behavior are presented.


BookDOI
01 Jan 1999
TL;DR: The authors argue for a distinction between the classical view of referential representation and the alternative concept of system-relative representation, which refers to situated cognitive processes whose dynamics are merely modulated by their environment rather than being instructed and determined by it.
Abstract: This paper discusses the notion of representation and outlines the ideas and questions which led to the organization of this volume. We argue for a distinction between the classical view of referential representation, and the alternative concept of system-relative representation. The latter refers to situated cognitive processes whose dynamics are merely modulated by their environment rather than being instructed and determined by it.

Journal ArticleDOI
TL;DR: An inner audience is an internal representation of others' values, goals, and standards for the self (other standpoint on self). It contrasts with an internal representations of one's own values, go...
Abstract: An inner audience is an internal representation of others' values, goals, and standards for the self (other standpoint on self). It contrasts with an internal representation of one's own values, go...

Journal Article
TL;DR: A practical framework for the semi-automatic construction of evaluation-functions for games based on a structured evaluation function representation is presented that is able to discover new features in a computationally feasible way.
Abstract: This paper discusses a practical framework for the semiautomatic construction of evaluation-functions for games. Based on a structured evaluation function representation, a procedure for exploring the feature space is presented that is able to discover new features in a computationally feasible way. Besides the theoretical aspects, related practical issues such as the generation of training positions, feature selection, and weight fitting in large linear systems are discussed. Finally, we present experimental results for Othello, which demonstrate the potential of the described approach.

Journal ArticleDOI
TL;DR: In this article, a connectionist model is proposed to predict the position of objects and initiate a response towards these objects, and the model predicts the presence of an early dissociation between surface features and spatial-temporal features when reasoning about hidden objects.
Abstract: Infants under 7 months of age fail to reach behind an occluding screen to retrieve a desired toy even though they possess sufficient motor skills to do so. However, even by 3.5 months of age they show surprise if the solidity of the hidden toy is violated, suggesting that they know that the hidden toy still exists. We describe a connectionist model that learns to predict the position of objects and to initiate a response towards these objects. The model embodies the dual-route principle of object information processing characteristic of the cortex. One route develops a spatially invariant surface feature representation of the object whereas the other route develops a feature blind spatial–temporal representation of the object. The model provides an account of the developmental lag between infants’ knowledge of hidden objects and their ability to demonstrate that knowledge in an active retrieval task, in terms of the need to integrate information across multiple object representations using (associative) connectionist learning algorithms. Finally, the model predicts the presence of an early dissociation between infants’ ability to use surface features (e.g. colour) and spatial–temporal features (e.g. position) when reasoning about hidden objects. Evidence supporting this prediction has now been reported.



Patent
06 Jan 1999
TL;DR: In this article, an original image is sharpened by obtaining a first frequency-domain representation of the original image, selecting one or more elements from this first representation based on one more criteria such as element magnitude and frequency, scaling the selected elements according to one or multiple scale factors, and combining the scaled selected elements with the unselected elements of the first representation.
Abstract: An original image is sharpened by obtaining a first frequency-domain representation of the original image, selecting one or more elements from this first representation based on one more criteria such as element magnitude and frequency, scaling the selected elements according to one or more scale factors, and forming a second frequency-domain representation by combining the scaled selected elements with the unselected elements of the first representation. A sharpened reproduction of the original image may be generated by applying an inverse transform to the second frequency-domain representation. A technique for deriving the value of the one or more scale factors is also discussed.



Patent
18 Oct 1999
TL;DR: In this article, the user can select an active region of a larger information area, resize it and zoom in or out by directly manipulating the graphic representation of the active area of data.
Abstract: A computer implemented graphical user interface and data processing method is provided that facilitates manipulation of objects on a display by directly manipulating a graphic representation of an active area of data. The user can select an active region of a larger information area, reposition it relative to the information area, resize it and zoom in or out by directly manipulating the graphic representation of the active area.

01 Jan 1999
TL;DR: The contribution model is formalized and extended so that it can be represented computationally; a method for combining the turns of two individual agents into one incrementally determined, coherent representation of the processes of dialog is presented.
Abstract: We formalize and extend the contribution model of Clark and Schaefer (1987, 1989) so that it can be represented computationally; we then present a method for combining the turns of two individual agents into one incrementally determined, coherent representation of the processes of dialog. This representation is intended to approximate what a participant might represent about the dialog so far, for the immediate purpose of referring, making contextual inferences, and repairing problems of understanding, as well as for the longer term purpose of storing the products of dialog in memory. Such an approach, we argue, is necessary for enabling a computer-based partner to converse in a way that seems natural to a human partner.