Logical diagnosis ofLDL programs

The debuggers of Ref. 11) and most of their derivatives are of themeta-interpreter type. The computation of the debugger tracks the computation of the program to be diagnosed at the level of procedure call. This is adequate if the intuitive understanding of the programmer is in terms of procedure calls; as is indeed the case in Prolog. InLDL however, while the semantics of the language are described in a bottom-up, fixpoint model of computation,⁸⁾ theactual execution of a program is a complex sequence of low-level procedure calls determined (and optimized) by the compiler. Consequently, a trace of these procedure calls is of little use to the programmer. Further, one cannot “execute” anLDL program as if it was a Prolog program; the program may simply not terminate in its Prolog reading and severalLDL constructs have no obvious Prolog counterparts. We identify the origin of a fault in theLDL program by a top-down, query/subquery approach. The basic debugger, implemented in Prolog, is a shell program between the programmer and theLDL program: it poses queries and uses the results to drive the interaction with the user. It closely resembles the one presented in Ref. 11). The core of a more sophisticated debugger is presented as well. Several concepts are introduced in order to quantify debugging abilities. One is that of agenerated interpretation, in which the structureless intended interpretation of Ref. 11) is augmented with causality. Another is the (idealized) concept of areliable oracle. We show that given an incorrect program and a reliable oracle which uses a generated interpretation, a cause for the fault will be found in finitely many steps. This result carries over to the more sophisticated debugger.     

Synthesis of Calcium Hexaboride by Electrolysis of Molten Salt

Metallurgical and Materials Transactions B - Formation of calcium hexaboride by means of electrodeposition of boron oxide in molten CaCl2 with additives of CaO and B2O3 was analyzed. It was shown...     

Procedural justice, stress appraisal, and athletes' attitudes.

In this study the authors examined a model in which procedural justice may serve as an external-situational resource that improves athletes' appraisals of stress and enhances their attitudes toward their team. Eighty-one Israeli male athletes were questioned on the degree of procedural justice employed on their team, how they appraised stress, and their attitudes toward their team. Results showed that higher procedural justice was associated with more positive appraisals of stress as a challenge and greater team loyalty and commitment and that the relationship of procedural justice to team commitment and loyalty was mediated by how stress is appraised. Findings integrate the cognitive-phenomenological model of stress/coping with the relational factors of the procedural justice approach and extend their validity to the field of sport. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A simple clinical test for differentiating physiological from pathological head lag in full-term newborn infants

The New Doctor paper recently published by the General Medical Council outlines the primarily educational role of preregistration house officers. This article illustrates one innovative way in which this is being implemented simultaneously with a significant service provision, often increasing the standard of patient care.     

Does repression exist? Memory, pathogenic, unconscious and clinical evidence.

The current dispute regarding the existence of repression has mainly focused on whether people remember or forget trauma. Repression, however, is a multidimensional construct, which, in addition to the memory aspect, consists of pathogenic effects on adjustment and the unconscious. Accordingly, in order to arrive at a more accurate decision regarding the existence of repression, studies relevant to all three areas are reviewed. Moreover, since psychoanalysis regards repression as a key factor in accounting for the development and treatment of neurotic disorders, relevant research from these two domains are also taken into account. This comprehensive evaluation reveals little empirical justification for maintaining the psychoanalytic concept of repression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mapping Datalog program execution to networks of processors

The problem of mapping the parallel bottom up execution of Datalog programs to an interconnected network of processors is studied. The parallelization is achieved by using hash functions that partition the set of instantiations for the rules. We first examine this problem in an environment where the number of processors and the interconnection topology is known, and communication between program segments residing at non-adjacent processors is not permitted. An algorithm is presented that decides whether a given Datalog program can be mapped onto such an architecture. We then relax the constraint on the architecture by allowing program segments residing at non-adjacent processors to communicate, A theory of approximate mappings is developed, and an algorithm to obtain the closest approximate mapping of a given Datalog program onto a given architecture is presented