Stacked graphs--geometry & aesthetics

In February 2008, the New York Times published an unusual chart of box office revenues for 7500 movies over 21 years. The chart was based on a similar visualization, developed by the first author, that displayed trends in music listening. This paper describes the design decisions and algorithms behind these graphics, and discusses the reaction on the Web. We suggest that this type of complex layered graph is effective for displaying large data sets to a mass audience. We provide a mathematical analysis of how this layered graph relates to traditional stacked graphs and to techniques such as ThemeRiver, showing how each method is optimizing a different “energy function”. Finally, we discuss techniques for coloring and ordering the layers of such graphs. Throughout the paper, we emphasize the interplay between considerations of aesthetics and legibility.      

Forgetting automata and context-free languages

 It is shown that context-free languages can be characterized by linear bounded automata with the following restriction: the head can either move right without rewriting or move left with erasing the current cell (i.e. rewriting it with a special, nonrewriteable, symbol). If, instead of erasing, we consider deleting (complete removing of the cell), the corresponding automata are less powerful. Received June 6, 1994/April 12, 1995     

Reconfigurable handling systems as an enabler for large components in mass customized production

Manufacturing companies today are exposed to increasingly dynamic market requirements. Particularly in high-wage countries, there is also a clear trend toward standing out from global competitors by means of product differentiation. At the same time, however, prices have to remain competitive. As a consequence, many companies choose a mass customization strategy to reconcile individualized products with advantages of the economies of scale. So far, this aim is mainly reached in the consumer goods sector by flexible production systems with a high degree of automation. The approach presented here is capable of transferring the benefits of mass customization to large products with lower production quantities such as aircraft by means of a highly reconfigurable automated handling system. Instead of manual operations or specific jigs and fixtures for each component, the new system is characterized by supporting large work pieces at several distributed points by multiple robotic arms. The individual robots are simple in design and very lightweight so that they can be easily switched in order to reconfigure the assembly system for different tasks. The development does not only comprise hardware construction, but also new methods for programming, commissioning and control of cooperating handling devices in a modular and reconfigurable system layout.     

Learnability and Definability in Trees and Similar Structures

We prove upper bounds for combinatorial parameters of finite relational structures, related to the complexity of learning a definable set. We show that monadic second-order (MSO) formulas with parameters have bounded Vapnik–Chervonenkis dimension over structures of bounded clique-width, and first-order formulas with parameters have bounded Vapnik–Chervonenkis dimension over structures of bounded local clique-width (this includes planar graphs). We also show that MSO formulas of a fixed size have bounded strong consistency dimension over MSO formulas of a fixed larger size, for labeled trees. These bounds imply positive learnability results for the PAC and equivalence query learnability of a definable set over these structures. The proofs are based on bounds for related definability problems for tree automata.     

Morphological image sequence processing

We present a morphological multi-scale method for image sequence processing, which results in a truly coupled spatio-temporal anisotropic diffusion. The aim of the method is not to smooth the level-sets of single frames but to denoise the whole sequence while retaining geometric features such as spatial edges and highly accelerated motions. This is obtained by an anisotropic spatio-temporal level-set evolution, where the additional artificial time variable serves as the multi-scale parameter. The diffusion tensor of the evolution depends on the morphology of the sequence, given by spatial curvatures of the level-sets and the curvature of trajectories (=acceleration) in sequence-time. We discuss different regularization techniques and describe an operator splitting technique for solving the problem. Finally we compare the new method with existing multi-scale image sequence processing methodologies.     

Conversational comprehension processes are responsible for reasoning fallacies in children as well as adults: If is not the biconditional.

Proposes that children do poorly on reasoning from premises of the form if p then q not because they construe if as a biconditional but rather because they use discourse comprehension processes that lead them to accept the invited inferences if not p then not q and if q then p. This hypothesis predicts that children should respond appropriately to premises in which the invited inferences are countermanded. In Exp I, 24 undergraduates and 44 10-yr-olds were given conditional reasoning problems. Some of these had a major premise consisting of a single if–then sentence, while others had a more elaborate major premise in which the invited inferences were explicitly countermanded. In Exp II, Ss were 24 undergraduates, 20 10-yr-olds, and 34 7-yr-olds. In some problems the major premise consisted of a single if–then statement; in others, the major premise consisted of 3 such statements, 2 of which shared the same consequent, thus implicitly countermanding the invited inferences. In both experiments, all age groups committed the fallacies in the simple condition but not in the more complex condition. It is concluded that children's representation of if distinguishes necessary from merely invited inferences. Data suggest a collection of countermandable context-dependent inferences of varying degrees of invitingness associated with if. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Whatever happened to neurosis? An overview.

Discusses the decision to eliminate the term "neurosis" from the DSM-III. The history of the term is traced; weaknesses of DSM-II pertaining to neurosis are presented; theoretical and political processes in the deletion procedure are described; and an overview is given of the current resolution as presented in DSM-III. Instead of neurosis, "neurotic disorder" and "neurotic process" were distinguished to reduce potential theoretical bias. The process may or may not be seen by the clinician as causal in the disorder, but those of all theoretical persuasions should be able to agree on what the disorder is. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in status generalization: Effects of need for social approval, anticipated interpersonal contact, and instrumental task abilities.

Conducted 2 studies to (a) extend the scope of the work done by J. Berger and his associates (1977) using expectation states theory and (b) test the hypothesis that need for social approval and differences in relative status between actors combine to structure the status-organizing process. A total of 337 undergraduate students in introductory psychology classes served as Ss. Design and procedures for the 2 studies and for each of the 4 experiments are described in detail. Study 1 focused on the role of normative dependence; Study 2 on the role of informational dependence. Overall, the findings are interpreted as supporting the idea that the construct of the need for social approval contains both an approval-seeking and a defensiveness components that are activated differently by the anticipation of personal contact and by the presence of a task ability that makes performance relevant to self concepts. (2? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Metadata requirements for digital museum environments

We describe a system which addresses all the processes involved in digitally acquiring, modelling, storing, manipulating and creating virtual exhibitions from 3D museum artefacts. More specifically, we examine the significance of metadata in enabling and supporting all of these processes and describe the extensive facilities provided for authoring, maintaining and managing metadata. The development of the system has been heavily influenced by factors relating to interoperability, standards, museum best practice and feedback from two museum pilot sites. Finally, we briefly consider the system in the wider context of applications such as virtual learning environments and distributed repositories of archives.     

Standardization of investment casting process using modified binder hydrolysis

A full factorial 2³ matrix was designed to study the bending strength, permeability and hoop-stress of investment moulds. A novel method of ethyl-silicate hydrolysis; two-step hydrolysis, was used. The results indicate that the bending strength is directly proportional to the quantity of filler material in the slurry. Grain size of stucco material appears to exert the least effect on bending and hoop strength, whereas permeability increases slightly when coarser grain is used.