Program Extraction from Normalization Proofs

This paper describes formalizations of Tait's normalization proof for the simply typed λ-calculus in the proof assistants Minlog, Coq and Isabelle/HOL. From the formal proofs programs are machine-extracted that implement variants of the well-known normalization-by-evaluation algorithm. The case study is used to test and compare the program extraction machineries of the three proof assistants in a non-trivial setting.     

Von der Erkenntnis des Sch?nen in der Kunst

Ohne Zusammenfassung     

Emotional valence modulates the preference for curved objects

Previous studies have shown that people prefer objects with curved contours over objects with sharp contours. However, those studies used stimuli that were mainly neutral in emotional valence. We tested here the interplay between visual features and general valence as positive or negative. After replicating curvature preferences for neutral objects, we used positive (cake, chocolate) and negative (snake, bomb) stimuli to examine if emotional valence-through response prioritisation-modulates the preference for curved objects. We found that people indeed preferred the curved versions of objects to the sharp versions of the same objects, but only if the objects were neutral or positive in emotional valence. There were no difference in liking for objects with negative emotional valence. This is evidence that the aesthetic response is adaptive, in this case prioritising valence over contour as demanded by the general semantic classification.     

A New Approach To The Identification Of Cognitive Conflicts In The Repertory Grid: An Illustrative Case Study

The concept of cognitive conflicts and its relation to the success of psychoanalytically oriented psychotherapy are discussed. According to this model of therapy, patients should achieve insight into their conscious as well as unconscious conflicts. Therefore in the present study we assumed that demonstrable cognitive changes would occur over treatment for chronic pain, as measured by Kelly's (1955) Repertory Grid Test. Grids were analyzed with regard to conflicts on the basis of the concept of unbalanced triads. A triad may be described as unbalanced when logical inconsistencies can be demonstrated on the basis of a correlative comparison of three corresponding construct pairs. Construct systems were checked for unbalanced triads by means of a new computer program derived by the authors. A case study serves to demonstrate the possibilities for analysis and interpretation of unbalanced triads offered by this novel method. Results indicate that cognitive restructuring had indeed taken place during therapy and had decreased the relative number of cognitive conflicts.     

Culture,Institutions, and Morally Dubious Behaviors: Testing Some Core Propositions of the Institutional-Anomie Theory

This study draws on self-report data on the prevalence of morally dubious behaviors in Europe to examine Messner and Rosenfeld's institutional-anomie theory. Institutional-anomie theory tries to explain cross-national differences in crime rates through the interplay between the cultural commitments and the institutional arrangements characterizing a society. The relevant state of research is unsatisfactory and full of gaps. Deficiencies exist, especially with regard to the postulated cultural dynamics. Findings from a series of multilevel models testing the combined effects of cultural forces and social institutions on respondents’ engagements in morally dubious behaviors that are committed in pursuit of self-interest—thereby controlling for differences in sociodemographic composition—shed doubt on the theory's explanatory power. Neither the cultural imperatives of the “American Dream” nor the extent of anomic orientations are linked in the expected manner to the observed cross-national variation in rates of moral misconduct across Europe.     

Torque levels, subjective discomfort, and muscle activity associated with four commercially available screwdrivers under static and dynamic work conditions

This study evaluated screwdrivers with different handle designs and blade lengths. 10 men and 10 women voluntarily participated. A repeated-measures experiment design was employed. The three independent factors were sex of user, handle (four types), and blade length (130, 170, and 210 mm). The dependent measures were the maximum supination torque under a static task and the %MVC of EMG responses in biceps brachii and flexor digitorum, and a discomfort rating for the upper extremity under the dynamic task. Analysis showed that the in-line screwdriver with the combined characteristics of large handle diameter (3.8-4.1 cm), smooth rubber covering handle surface, triangular (or circular) shape, and adequate handle length (11 cm) had the greatest supination torque and a smaller discomfort rating than the screwdriver with the pistol-grip handle. Blade length was not significantly related to any dependent measure.