In this paper, a methodology for constructing hierarchical and structured predicate transition net specifications is developed, which includes new systematic notation extensions for supporting various transformation techniques upon predicate transition nets and several rules for applying such transformation techniques. The levelling technique in data‐flow diagrams is adapted in the refinement and the abstraction techniques, and the state decomposition idea in state‐charts is employed in designing various label formulation operators. The methodology is illustrated through the specification of a lift system. The methodology can significantly reduce the constructing complexity and enhance the comprehensibility of large predicate transition net specifications.

This paper presents some results of integrating predicate transition nets with first order temporal logic in the specification and verification of concurrent systems. The intention of this research is to use predicate transition nets as a specification method and to use first order temporal logic as a verification method so that their strengths-the easy comprehension of predicate transition nets and the reasoning power of first order temporal logic can be combined. In this paper, a theoretical relationship between the computation models of these two formalisms is presented; an algorithm for systematically translating a predicate transition net into a corresponding temporal logic system is outlined; and a special temporal refutation proof technique is proposed and illustrated in verifying various concurrent properties of the predicate transition net specification of the five dining philosophers problem.

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In this paper, we evaluate the effects of applying programming language subsets to the programming environment used by novice (CS1) students in a closed-laboratory setting, as well as reducing the complexity of the user interface for the environment. Our goal in this effort was to assess if such interface and application-level changes adversely impact the student or hinder the later migration to a traditional professional-strength programming environment.We focus on the comparison of the quantitative data captured from the closed-laboratory sessions (assignment grades, number of syntax / semantic errors, and the number of compilation / execution attempts) involving subjects that used a new programming environment featuring a less complex interface in two forms: one lacking support of language subsets, and one supporting the application of language subsets.We found that while using the environment supporting the application of language subsets, there was no difference in the compilation-attempt rate, the number of errors did not increase, and student grades were equivalent between the experiment groups. Additionally, following a migration to the professional environment from the simplified environment, student grades were equivalent to those that had used the professional environment throughout the experiment. Student reaction to the experimental environment was very positive, especially related to the removal of unused tools and project management features.

This paper provides an overview of the history of computing and its affect on computing in education. It describes the evolution of the history of computing through activities such as conferences, collection and archival activities, individual collections, books and journals, and websites. It also illustrates the use of computers in the history of education in areas such as computing education, engineering, home and office, and the classroom. The paper brings light the importance of history in fulfilling the legacy of different areas of learning.