Abstract: How many types of errors can be detected through static analysis and branch testing? How many man-hours and machine hours do these techniques require? Here are some empirically determined answers.

Abstract: A new subclass of Petri Nets is presented called the "Extended Control Structure Nets". The control structure of arbitrarily structured parallel programs can be represented by nets of this class, even if they include operations on general semaphores. First of all, the purely statical structure of the Extended Control Structure Nets is dealt with, i.e. the graph of these nets. It is defined, in which way these nets are recursively generated by a composition of connected state machines which in turn represent the control structure of sequential parts of a parallel program or event variables resp. semaphores. Various properties of these graphs of Extended Control Structure Nets are stated. In addition, some special paths in these graphs are defined which are meaningful in respect to the underlying interpretation and thus are important for the later structural analysis. By the inclusion of markings and the corresponding standard definitions, the full modelling power of Extended Control Structure Nets is introduced in respect to the dynamical behaviour of parallel programs. The notion of liveness is given in terms of reachable markings. Finally, necessary and sufficient conditions are given for the liveness of Extended Control Structure Nets. This result offers the conceptual framework for the following proposal: o Represent the control structure of parallel programs by Extended Control Structure Nets. o Check (at compile-time) if all the seven liveness conditions are satisfied for a parallel program. o If they are satisfied the analyzed program will be deadlock-free.

Abstract: A computer program with acronym GLASS-II is described. This code is based on the concept of global--local finite elements, wherein both contemporary finite element and classical Rayleigh--Ritz approximations are simultaneously employed. The library of elements in GLASS-II include the axisymmetric element, planar element, three-dimensional solid element, plate bending element, and shell element. Moreover, for the axisymmetric and planar elements, general loading conditions can be treated by their expansion in terms of Fourier series. Derivation of the element matrices and consistent load vectors are described in detail. A brief description of the GLASS-II computer code is given, which at the present time is checked out for static analysis problems. A version with dynamic analysis capabilties is forthcoming. Instructions concerned with the programming of the global functions (a term used to denote the Rayleigh--Ritz approximations) are provided. These functions depend on the problem to be analyzed and must be provided by the user/analyst. The user's manual is contained in Appendix I and the computer listing of the GLASS-II code appears as Appendix I and the computer listing of the GLASS-II code appears as Appendix II. This code has been applied to the calculation of stress intensity factors and to problems involving amore » half-space. These applications evince the modeling versatility and computational effectiveness inherent in global--local finite element analysis. 10 figures.« less