Two-dimensional Perspective Research Articles

A Two-Dimensional Perspective on Attractive Quality

Attractive quality has for two decades been accentuated as a strong driver of loyalty, word-of-mouth and saleability. Recent elaborations of the concept of attractive quality however point to obstacles to the development of quality practices, such as engineering methods, to support the creation of attractive quality in practice. One obstacle is the lack of explanations as to why certain aspects of an offer are perceived as an attractive quality. There is a need to understand why attractive quality occurs. This paper aims to address these obstacles by presenting the results of a search for mechanisms claimed to cause attractive quality in literature. As a result, the paper identifies and relates two fundamentally different mechanisms considered important for the generation of attractive quality. The need-based roots of attractive quality point at an explanation in terms of the satisfaction of high-level needs. This is in sharp contrast to the currently dominant explanation of attractive quality as the exceeding of expectations. The two mechanisms are further distinguished and related to each other resulting in the classification of three different types of attractive quality. The three types are designated as ‘Surprisers’, ‘Life Enrichers’, and ‘Attraction Boosters’. The ‘Life Enrichers’, which are defined as satisfying high-level needs of the customer, are highlighted as an important and promising area for future research.

Descriptions of membrane mechanics from microscopic and effective two-dimensional perspectives

Mechanics of fluid membranes may be described in terms of the concepts of mechanical deformations and stresses, or in terms of mechanical free-energy functions. In this paper, each of the two descriptions is developed by viewing a membrane from two perspectives: a microscopic perspective, in which the membrane appears as a thin layer of finite thickness and with highly inhomogeneous material and force distributions in its transverse direction, and an effective, two-dimensional perspective, in which the membrane is treated as an infinitely thin surface, with effective material and mechanical properties. A connection between these two perspectives is then established. Moreover, the functional dependence of the variation in the mechanical free energy of the membrane on its mechanical deformations is first studied in the microscopic perspective. The result is then used to examine to what extent different, effective mechanical stresses and forces can be derived from a given, effective functional of the mechanical free energy.

Leaf vascular systems in C(3) and C(4) grasses: a two-dimensional analysis.

It is well documented that C(4) grasses have a shorter distance between longitudinal veins in the leaves than C(3) grasses. In grass leaves, however, veins with different structures and functions are differentiated: large longitudinal veins, small longitudinal veins and transverse veins. Thus, the densities of the three types of vein in leaves of C(3) and C(4) grasses were investigated from a two-dimensional perspective. Vein densities in cleared leaves of 15 C(3) and 26 C(4) grasses representing different taxonomic groups and photosynthetic subtypes were analysed. The C(4) grasses had denser transverse veins and denser small longitudinal veins than the C(3) grasses (1.9 and 2.1 times in interveinal distance), but there was no significant difference in large longitudinal veins. The total length of the three vein types per unit area in the C(4) grasses was 2.1 times that in the C(3) grasses. The ratio of transverse vein length to total vein length was 14.3 % in C(3) grasses and 9.9 % in C(4) grasses. The C(3) grasses generally had greater species variation in the vascular distances than the C(4) grasses. The bambusoid and panicoid C(3) grasses tended to have a denser vascular system than the festucoid C(3) grasses. There were no significant differences in the interveinal distances of the three vein types between C(4) subtypes, although the NADP-malic enzyme grasses tended to have a shorter distance between small longitudinal veins than the NAD-malic enzyme and phosphoenolpyruvate carboxykinase grasses. It seems that C(4) grasses have structurally a superior photosynthate translocation and water distribution system by developing denser networks of small longitudinal and transverse veins, while keeping a constant density of large longitudinal veins. The bambusoid and panicoid C(3) grasses have a vascular system that is more similar to that in C(4) grasses than to that in the festucoid C(3) grasses.

The Role Model of the Board: a preliminary study of the roles of Icelandic boards

The aim of this paper is to distinguish between different roles of boards of directors in companies and to fit the theoretical debate into a framework for better understanding. A simple framework, constructed from the literature, is used to distinguish between the archetypes of roles from a two-dimensional perspective. The paper includes a preliminary qualitative study of Icelandic companies with the aim of testing the framework and exploring the roles of boards in Iceland. The study shows that boards have various roles or patterns of roles and that the roles can change with change of circumstances.

Pattern Tracking and 3-D Motion Reconstruction of a Rigid Body From a 2-D Image Sequence

This paper presents an integrated method to identify an object pattern from an image, and track its movement over a sequence of images. The sequence of images comes from a single perspective video source, which is capturing data from a precalibrated scene. This information is used to reconstruct the scene in three-dimension (3-D) within a virtual environment where a user can interact and manipulate the system. The steps that are performed include the following: i) Identify an object pattern from a two-dimensional perspective video source. The user outlines the region of interest (ROI) in the initial frame; the procedure builds a refined mask of the dominant object within the ROI using the morphological watershed algorithm. ii) The object pattern is tracked between frames using object matching within the mask provided by the previous and next frame, computing the motion parameters. iii) The identified object pattern is matched with a library of shapes to identify a corresponding 3-D object. iv) A virtual environment is created to reconstruct the scene in 3-D using the 3-D object and the motion parameters. This method can be applied to real-life application problems, such as traffic management and material flow congestion analysis.

Signal Detection Theory Applied to Size Constancy in Virtual Environments

Pictorial depth cues and instructional set are two factors that influence the degree to which size constancy maintains in static two-dimensional perspective displays. Signal detection theory (SDT) allows the determination of whether these factors influence observers' sensitivity to perceived size (d') versus their subjective criteria (bias) for making ”same” or ”different” discriminative responses. Two objects were presented at various perceived distances in static perspective displays that varied in number of available pictorial depth cues. Observers made comparative size judgments regarding the objects' apparent distal size (phenomenal instructions) or objective distal size (objective instructions). Observers showed greater sensitivity to distal size differences when responding to apparent, rather than objective size differences. The presence of more pictorial depth cues produced greater sensitivity than a reduced-cue condition, especially under objective instructions. Overall, results indicate that SDT reveals aspects of size perception in pictorial displays not assessed through more traditional analyses based solely on accuracy.

Entropy of the 3-brane and the AdS/CFT duality from a two-dimensional perspective

A two-dimensional (2D) scalar–tensor gravity theory is used to describe the near-horizon, near-extremal behaviour of black 3-brane solutions of type IIB string theory. The asymptotic symmetry group of the 2D, asymptotically anti de Sitter (AdS) metric, is generated by a Virasoro algebra. The (non-constant) configuration of the 2D scalar field, which parametrizes the volume of the 3-brane, breaks the conformal symmetry and produces a divergent central charge in the Virasoro algebra. Using a renormalization procedure, we find a finite value for the central charge and, by means of the Cardy formula, the entropy of the black 3-brane in terms of microstates of the conformal field theory living on the boundary of the 2D spacetime. We find for the entropy as a function of the temperature the power-law behaviour S ∝ T3. Unfortunately, owing to a scale symmetry of the 2D model the proportionality constant is undetermined. The black 3-brane case is a nice example of how finite temperature effects in higher dimensional AdS/CFT dualities can be described by a AdS2/CFT1 duality endowed with a scalar field that breaks the conformal symmetry and produces a non-vanishing central charge.

How to approach the ENS: various ways to analyse motility disorders in situ and in vitro.

Motility disorders of the human intestine are so variable that they cannot be diagnosed by just one technique. Their aetiology is obviously so varied that they have to be approached with a broad range of technical methods. These reach from the simple haematoxylin-stained section to the isolation of stem or precursor cells. In this study, various methods to investigate the enteric nervous system and its surrounding tissue are demonstrated. While sections from paraffin-embedded material or cryostat sections provide only a two-dimensional perspective of the ENS, the whole-mount method yields three-dimensional perspectives of large areas of the gut wall. The three-dimensional impression can even be enhanced by electron microscopy of the isolated ENS. Dynamical aspects of ENS development can be tackled by in vitro studies. The myenteric plexus can be isolated and cultivated under the influence of the microenvironment (protein extracts). Although the postnatal myenteric plexus is not fully developed, the choice of embryological neuronal cells seems to be more effective for certain approaches. They can be isolated from the embryonic mouse gut and cultivated under the influence of various factors. This method seems to us a valuable tool for the investigation of the aetiology of motility disorders, although only a "complete" approach which considers all available methods will yield at the end a clear understanding which might lead to new therapeutical concepts.

Self-Esteem and Ethnic and National Identification among Adolescents in the Netherlands

ABSTRACT The great majority of studies on the self-esteem of ethnic minority youth has been conducted in the United States, has focused on global personal self-esteem only, and has not considered the issue of dual group identity. Using a two-dimensional perspective we examined ethnic and national identification and its relationship to global self-esteem and self-evaluation in six separate domains. Analyses of data collected in the Netherlands showed that for ethnic minority group adolescents, ethnic identification and national identification were independent of one another. In addition, ethnic identification was positively related to self-esteem whereas national identification was not. Furthermore, compared to the Dutch, ethnic minorities had similar levels of self-esteem and domain specific self-evaluations. Among all groups, physical appearance was clearly the most important predictor of global self-esteem. The results support a two-dimensional conceptualisation of identification for ethnic minority adolescents. The paper also argues that studies on self-esteem should examine different domains of self-evaluation in addition to global self-esteem. Furthermore, the results suggest that not only ethnocultural factors, but also more general factors are important for shaping self-evaluation among adolescents.

Simulation of mild wear in helical gears

A computer model for simulation of the wear behaviour in helical gears has been developed. The method used can deal with tooth modifications and different profiles. The authors have studied the effects of wear previously but only in a two-dimensional perspective. The objective of the paper is to compare the wear behaviour of gears using different approaches. The gear teeth in this model are regarded as thin uncoupled slices; the slicing method is valid when the contact area is narrow in the rolling direction, which is the case for contacting gear teeth. The pressure distribution on each slice is calculated using the well-known theories of Hertz assuming an infinitely wide line-contact. When the pressure and velocity on the surfaces are known, a modified Archard's wear equation is applied to calculate wear depths on the teeth. The simulation is an initial value problem since a complete mesh cycle is repeated a number of times with gradually changing surfaces due to the wear, which is being integrated over each time step.

Visualisation of urban surface temperatures derived from satellite images

A model for interpolating 2D thermal satellite data over a 3D urban surface is described, which combines the ViSC and GIS functions inherent in a modern GIS interface. Vertical surfaces are represented as spatial entities whose temperature attributes are determined from image data supplemented by field sampling in urban canyons. Thus a model representing the temperature of the complete urban surface is created, for which the viewpoint can be varied according to Sun angle and azimuth at the time of imaging and the viewing angle required by the user. Due to the close correspondence between surface and air temperature the model indicates micro-scale climatic variations due to variations in building geometry and surface materials which are not readily apparent from a twodimensional perspective. It also illustrates the magnitude of systematic error introduced by the nadir viewing angle of satellite sensors.

Recognition and pose estimation of unoccluded three-dimensional objects from a two-dimensional perspective view by banks of neural networks

This paper describes a neural network (NN) based system for recognition and pose estimation of an unoccluded three-dimensional (3-D) object from any single two-dimensional (2-D) perspective view. The approach is invariant to translation, orientation, and scale. First, the binary silhouette of the object is obtained and normalized for translation and scale. Then, the object is represented by a set of rotation invariant features derived from the complex orthogonal pseudo-Zernike moments of the image. The recognition scheme combines the decisions of a bank of multilayer perceptron NN classifiers operating in parallel on the same data. These classifiers have different topologies and internal parameters, but are trained on the same set of exemplar perspective views of the objects. Next, two pose parameters, elevation and aspect angles, are obtained by a novel two-stage NN system consisting of a quadrant classifier followed by NN angle estimators. Performance is tested on clean and noisy data bases of military ground vehicles. Comparative studies with three other classifiers (a single NN, the weighted nearest-neighbor classifier, and a binary decision tree) are carried out.

Determining camera parameters from the perspective projection of a quadrilateral

In this paper we show that there is sufficient information in the two-dimensional perspective projection of an arbitrary quadrilateral of known shape and size in three-space to determine the exact three-dimensional coordinates of its vertices, generalizing known results for rectangles. Implementation results are also discussed.

Evidence accumulation & flow of control

A fundamental goal of computer vision is the development of systems capable of carrying out scene interpretation while taking into account all the available knowledge. In this article, we focus on how the interpretation task can be aided by the expected scene information (such as map knowledge), which, in most cases, would not be in registration with the perceived scene. The proposed approach is applicable to the interpretation of scenes with three-dimensional structures as long as it is possible to generate the equivalent two-dimensional orthogonal or perspective projections of the structures in the expected scene. The system is implemented as a two-panel, six-level blackboard and uses the Dempster-Shafer formalism to accomplish inexact reasoning in a hierarchical space. Inexact reasoning involves exploiting, at different levels of abstraction, any internal geometric consistencies in the data and between the data and the expected scene. As they are discovered, these consistencies are used to update the system's belief in associating a data element with a particular entity from the expected scene.

Computer graphic display method for visualizing three-dimensional biological structures.

A computer graphic display method that produces two-dimensional perspective views of three-dimensional objects is presented. The method is applied to the reconstruction at a resolution of 2.2 nanometers of the neck of bacteriophage phi 29, obtained from transmission electron micrographs processed by the direct Fourier method. The combined use of directed illumination, reflectance models, color, and different levels of transparency provides a powerful tool for a better interpretation of the three-dimensional structure, allowing improved correlation with genetic, structural, and biochemical data.

Reaffirming the Importance of Strategic Use

Focusing exclusively on the substantive use of policy analysis results in a limited assessment of the role of analysis in policymaking, particularly in a congressional setting. This article develops a two-dimensional perspective on use, incorporating a substantive-strategic dimension as well as a concrete-conceptual dimension. The importance of this perspective is demonstrated through an analysis of congressional use of two projects produced by the congressional Office of Technology Assessment, one on coal slurry pipelines and the other on residential energy conservation. Results indicate both the existence of substantive use and the importance of more strategic uses.

Tracking three dimensional moving light displays (abstract only)

A method is presented for tracking the three-dimensional motion of points from their changing two-dimensional perspective images as viewed by a nonconvergent binocular vision system. The algorithm relies on a general smoothness assumption to guide the tracking process, and application of the tracking algorithm to a three-dimensional moving light display based on Cutting's Walker program as well as other domains are discussed.Evidence is presented relating the tracking algorithm to certain beliefs about neurophysiological structures in the visual cortex.

Solving camera parameters from the perspective projection of a parameterized curve

Given the two-dimensional perspective projection of a known conic or polygon of unknown size and position in three-dimensional space, we show how to determine the camera look angles relative to the plane where the curve lies. Separate cases are discussed for conic and polygons. We then show that this technique can be used to solve for any planar or nonplanar curves, as long as they can be represented in parametric forms.

Identification of Space Curves from Two-Dimensional Perspective Views

This paper describes a new method to be used for matching three-dimensional objects with curved surfaces to two-dimensional perspective views. The method requires for each three-dimensional object a stored model consisting of a closed space curve representing some characteristic connected curved edges of the object. The input is a two-dimensional perspective projection of one of the stored models represented by an ordered sequence of points. The input is converted to a spline representation which is sampled at equal intervals to derive a curvature function. The Fourier transform of the curvature function is used to represent the shape. The actual matching is reduced to a minimization problem which is handled by the Levenberg-Marquardt algorithm [3].

Perspective display of patient external and internal contours

The two-dimensional perspective display of three-dimensional patient contour data is useful in radiotherapy treatment planning as it provides a comprehensive view of the relative positions of patient internal (organ and target) and external contours. The advent of minicomputers and video display systems has made possible the integration of such display techniques into the treatment planning routine. This paper describes and gives an example of the methods we have found useful in producing perspective displays of patient contour data. Included is a solution to the problem of removing hidden line segments from the displayed image.