Prototypical Shape Research Articles

Automatic segmentation of metaphase cells based on global context and variant analysis

We treat the problem of chromosome segmentation with the aid of shape analysis and classification. Our approach consists of a combination of two phases, a purely rule-based phase and a phase driven by constrained discriminant analysis. In the first phase, obvious prototypical shape elements related to touchings and overlaps are recursively identified, in the second, remaining complex and ambiguous cases are treated. The latter phase exploits global context by using variant analysis, a statistical theory of ambiguity recently established. The method turns out to be quite accurate. The system works on whole clinical cells and to a certain degree when band patterns are not or not well visible.

Shapeme histogram projection and matching for partial object recognition

Histograms of shape signature or prototypical shapes, called shapemes, have been used effectively in previous work for 2D/3D shape matching and recognition. We extend the idea of shapeme histogram to recognize partially observed query objects from a database of complete model objects. We propose representing each model object as a collection of shapeme histograms and match the query histogram to this representation in two steps: 1) compute a constrained projection of the query histogram onto the subspace spanned by all the shapeme histograms of the model and 2) compute a match measure between the query histogram and the projection. The first step is formulated as a constrained optimization problem that is solved by a sampling algorithm. The second step is formulated under a Bayesian framework, where an implicit feature selection process is conducted to improve the discrimination capability of shapeme histograms. Results of matching partially viewed range objects with a 243 model database demonstrate better performance than the original shapeme histogram matching algorithm and other approaches.

Efficient shape matching using shape contexts

We demonstrate that shape contexts can be used to quickly prune a search for similar shapes. We present two algorithms for rapid shape retrieval: representative shape contexts, performing comparisons based on a small number of shape contexts, and shapemes, using vector quantization in the space of shape contexts to obtain prototypical shape pieces.

The motivation to control and the origin of mind: Exploring the life–mind joint point in the Tree of Knowledge System

The evolved function of brain, cognitive, affective, conscious-psychological, and behavioral systems is to enable animals to attempt to gain control of the social (e.g., mates), biological (e.g., prey), and physical (e.g., nesting spots) resources that have tended to covary with survival and reproductive outcomes during the species' evolutionary history. These resources generate information patterns that range from invariant to variant. Invariant information is consistent across generations and within lifetimes (e.g., the prototypical shape of a human face) and is associated with modular brain and cognitive systems that coalesce around the domains of folk psychology, folk biology, and folk physics. The processing of information in these domains is implicit and results in automatic bottom-up behavioral responses. Variant information varies across generations and within lifetimes (e.g., as in social dynamics) and is associated with plastic brain and cognitive systems and explicit, consciously driven top-down behavioral responses. The fundamentals of this motivation-to-control model are outlined and links are made to Henriques' (2004) Tree of Knowledge System and Behavioral Investment Theory.

Application of the non-adiabatic phase matrix method to vibrational excitation near a short-lived resonance: the case of scattering

We have applied the non-adiabatic phase matrix method for vibrational scattering processes to a system which supports an extremely broad (short-lived) shape resonance. This method provides a unified, systematic treatment of the range of physical effects that influence the collision as the nuclear geometry varies, from strongly resonant to purely background scattering. For this implementation we have chosen the prototypical shape resonance in scattering below 10 eV. We compare vibrational cross sections and from the present non-adiabatic theory to results from fully converged body-frame vibrational close-coupling calculations and from purely adiabatic studies using the energy modified approximation.

PURE ALEXIA AND THE VIEWING POSITION EFFECT IN PRINTED WORDS

In the present article, we investigated the reading ability of CP, a pure alexic patient, using an experimental paradigm that is known to elicit the viewing position effect in norm al readers. The viewing position effect consists of a systematic variation of word recognition performance as a function of fixation location w ithin a word: Word recognition is best when the eyes fixate slightly left from the word centre and decreases when the eyes deviate from this optimal viewing position. A mathematical model (Nazir, O'Regan, & Jacobs, 1991), which provides a good description and quantification of the prototypical shape of the viewing position effect, served to interpret CP's reading performance. The results show ed that, like normal readers, CP was able to process all letters of a w ord in one fixation. However, in contrast to normal readers, reading performance was optimal when CP w as fixating the right half of the word. This somewhat abnormal pattern of performance was due to (1) poor perceptual processing in the right visual field, and (2) poor processing of letters situated towards the end of the word, independent of visual field presentation. A similar pattern of perform ance w as obtained with normal readers under experimental conditions in which lexical know ledge was of restricted use. We suggest that CP's reading impairment stems from a dysfunction in the coupling between incoming visual information and stored lexical information. This dysfunction is thought to uncover a prelexical level of word processing, where letter information is weighted differently as a function of letter position in a word-centred space.

Vilification of Identity and the Exilic Narrative: The Illustrated Pied Piper Story

In the life time of the species and in the course of individual biographies, human beings build well-defined worlds of meaning by which to organize and interpret experience. There is perhaps no greater demonstration of this world-building process than that carried out through the verbal and visual activity of story telling.This paper, traces the visible footsteps of one story in particular, “The Pied Piper of Hamelin.” First, it presents the origins of its dominant symbols in the visual culture of the community where it is initially told. Second, it shows how illustrated folktales like this one remain a significant aspect of what is called the visual socialization of children. Historically and cross-culturally, norms of meaning and visual meaning groups use to make sense of hu experience are transmitted to children in this way, as they begin their own world-building process.This paper situates The Pied Piper story as an exilic narrative, part of a larger repertoire of stories that follow the romantic quest-myth formula, a formula that conveys a total metaphor for the “journey of life.” By its verbal and visual narration, we teach this formula to every new generation as a way of ordering and interpreting experience. From the late 1200’s to the late 1900’s, this quest-myth retains its prototypical shape as it unfolds before new audiences, the Piper clothed in the archetypal garb of one who is marked for exile. Read this way, the illustrated texts of childhood provide an entirely legible architectural history of the world-building activity of generations.

A shape analysis model with applications to a character recognition system

A method for the recognition of multifont printed characters is proposed, giving emphasis to the identification of structural descriptions of character shapes using prototypes. Noise and shape variations are modeled as series of transformations from groups of features in the data to features in each prototype. Thus, the method manages systematically the relative distortion between a candidate shape and its prototype, accomplishing robustness to noise with less than two prototypes per class, on average. The method uses a flexible matching between components and a flexible grouping of the individual components to be matched. A number of shape transformations are defined, including filling of gaps, so that the method handles broken characters. Also, a measure of the amount of distortion that these transformations cause is given. Classification of character shapes is defined as a minimization problem among the possible transformations that map an input shape into prototypical shapes. Some tests with hand-printed numerals confirmed the method's high robustness level.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Rubbing your stomach while tapping your fingers: Interference between motor planning and semantic judgments.

Previous research (Klatzky et al., 1989) shows that the time required to make sensible/nonsensible judgments about an action-object phrase (e.g., "rub your stomach") is reliably faster when the phrase is preceded by a cure representing a specific prototypical hand shape (vs. a neutral cue). The current experiments investigated the effects of preparing for an alternate task (finger tapping vs. syllable vocalization) on facilitatory priming of sensibility judgments. Preparation for finger tapping reduced the magnitude of the priming effect more than preparation for vocalization, suggesting that resources accessed during semantic processing of action-object phrases are also used during manual response preparation. The results support the existence of a system representing manual actions that is limited in the number of activities that can be represented at one time and that is not so general that it represents manual and vocal tract movements.

Can you squeeze a tomato? The role of motor representations in semantic sensibility judgments

Five experiments assessed whether priming a hand shape facilitated judgments about the sensibility of actions performed with objects. Primes specified the hand shape's size (full hand or part) and whether operative fingers were flexed or extended. These dimensions define four prototypical shapes: pinch (part, flexed), poke (part, extended), clench (full, flexed), and palm (full, extended). Primes were verbal in Experiments 1–3 and “iconic” in Experiments 4–5. In Experiments 1–4, subjects were initially trained to enact the shape, given a prime. They then judged the sensibility of verbal action/object pairs, such as “eat a carrot,” which were preceded by a neutral or informative prime. Response times were consistently reduced, relative to the neutral condition, when both dimensions of the hand shape were primed. In Experiment 5, subjects were trained to vocalize a hand-shape label, given a prime, and no priming effect subsequently occurred. These results suggest a cognitive/motoric representation of the hand with which actions on objects can be modeled, and the results can be interrogated.

Electrical circuit modeling of conductors with skin effect

The electrical impedance of a lossy conductor is a complicated function of time (or frequency) because of the skin effect. By solving the diffusion equation for magnetic fields in conductors of several prototypical shapes, the impedance can be calculated as a function of time for a step function of current. The solution suggests an electrical circuit representation that allows calculation of time-dependent voltages and currents of arbitrary waveforms. A technique using an operational amplifier to determine the current in such a conductor by measuring some external voltage is described. Useful analytical approximations to the results are derived.