The Search for the Laws of Automatic Random Testing

Can one estimate the number of remaining faults in a software system? A credible estimation technique would be immensely useful to project managers as well as customers. It would also be of theoretical interest, as a general law of software engineering. We investigate possible answers in the context of automated random testing, a method that is increasingly accepted as an effective way to discover faults. Our experimental results, derived from best-fit analysis of a variety of mathematical functions, based on a large number of automated tests of library code equipped with automated oracles in the form of contracts, suggest a poly-logarithmic law. Although further confirmation remains necessary on different code bases and testing techniques, we argue that understanding the laws of testing may bring significant benefits for estimating the number of detectable faults and comparing different projects and practices.Comment: 20 page

Proceedings of the Eighth Annual Software Engineering Workshop

The four major topics of discussion included: the NASA Software Engineering Laboratory, software testing, human factors in software engineering and software quality assessment. As in the past years, there were 12 position papers presented (3 for each topic) followed by questions and very heavy participation by the general audience

Human factors aspects of control room design: Guidelines and annotated bibliography

A human factors analysis of the workstation design for the Earth Radiation Budget Satellite mission operation room is discussed. The relevance of anthropometry, design rules, environmental design goals, and the social-psychological environment are discussed

Studies of molecular properties of polymeric materials

Aerospace environment effects (high energy electrons, thermal cycling, atomic oxygen, and aircraft fluids) on polymeric and composite materials considered for structural use in spacecraft and advanced aircraft are examined. These materials include Mylar, Ultem, and Kapton. In addition to providing information on the behavior of the materials, attempts are made to relate the measurements to the molecular processes occurring in the material. A summary and overview of the technical aspects are given along with a list of the papers that resulted from the studies. The actual papers are included in the appendices and a glossary of technical terms and definitions is included in the front matter

Exploring the Role of Simulation and Visualization Tools in Improving Learning Outcomes in Support of Technology Programs

Online educational opportunities have provided students with the flexibility to advance their careers and complete certificate and degree programs. These have also provided educational institutions with increased capacity without the investment of costly brick-and-mortar expansions at campuses. Technology programs, however, have shied away from integrating these advances due to their program outcomes being heavily dependent on the use of tools and hands-on learning. This dissertation explores the use of digital learning lectures on linear measuring instruments accompanied with virtual reality tools in technology programs and its effects on both cognitive and psychomotor learning outcomes compared to current modality - face-to-face instruction. The research then investigates the differences in problem-solving self-efficacy and transfer of knowledge that occurs between the two groups. All three studies refer back to the Vygotsky\u27s Zone of Proximal Development as the theoretical framework (1978). The initial study recruited participants from entry level mathematics courses. It aimed to determine if the digital learning group performed at least as well as the conventional learning group in the educational gains, in skilled-based assessment scores, and perception of learning measures. Additional measures for the digital learning environment were collected to determine usability, technology acceptance, and workload. The between subjects experimental analysis showed statistical difference in the cognitive gains in favor of the digital learning group, but no statistical difference in the skilled-based assessment scores nor the perception of learning measures. A post hoc power analysis determined that a sample size of 102 participants, 51 per group, would be needed to obtain a statistical power at the recommended 0.80 level for a one-tailed test (Cohen, 1988). The second study replicated the first study with adjustments based on lessons learned and a larger sample size (N=86). One major change was that the participants were recruited from first semester students in automotive, aircraft maintenance, and avionics technology programs. This population better reflects the target population for the topic selected to test, metrology. Similar to the initial pilot study, the large scale study aimed to determine the effects of the digital learning materials on the educational gains, in skilled-based assessment scores, and perception of learning measures. The between subjects experimental analysis showed no statistical difference in the cognitive gains nor in the skilled-based assessment scores. However, the results did show statistical difference in the perception of learning measures in favor of the conventional learning group. The final study utilized a subset of the population from the large-scale study for a two-fold investigation: (1) problem-solving self-efficacy scores before and after completing a complex metrology task and (2) the transfer of knowledge that was uncovered during the completion of a complex metrology task. For the former, no significant difference was found in the pre- or post- problem solving self-efficacy scores between the digital learning group and the control group. In addition, both groups experienced positive self-efficacy gains after completing the complex task. These gains were also not statistically significantly different from one another. A transfer of knowledge framework by Rebello et al, (2005) and Hutchinson (2011) was used to analyze think aloud interviews conducted during the completion of a complex task. These revealed various instances of problem feature identification (target tool), mental processes to obtain an answer (workbench), and scaffolded and spontaneous transfer. In addition, themes emerged regarding the measurement systems used and the effectiveness of the digital learning environment. The implications of this work apply to the development of digital learning environments and virtual reality tools for 2-year technology programs. The performance based findings failed to reject that hypothesis that the digital learning group performed as least as well as the conventional learning group. Thus, we can recommend use of the digital learning environment to achieve at least the same mastery level. The qualitative findings, however, showed that participants did not feel that the digital learning environment prepared them well. Therefore, further attention should be paid to the development, scaffolding, and feedback loops of the digital learning environment in order to improve the perception of participants

Genetic dissection of heterosis using epistatic association mapping in a partial NCII mating design

Heterosis refers to the phenomenon in which an F1 hybrid exhibits enhanced growth or agronomic performance. However, previous theoretical studies on heterosis have been based on bi-parental segregating populations instead of F1 hybrids. To understand the genetic basis of heterosis, here we used a subset of F1 hybrids, named a partial North Carolina II design, to perform association mapping for dependent variables: original trait value, general combining ability (GCA), specific combining ability (SCA) and mid-parental heterosis (MPH). Our models jointly fitted all the additive, dominance and epistatic effects. The analyses resulted in several important findings: 1) Main components are additive and additive-by-additive effects for GCA and dominance-related effects for SCA and MPH, and additive-by-dominant effect for MPH was partly identified as additive effect; 2) the ranking of factors affecting heterosis was dominance > dominance-by-dominance > over-dominance > complete dominance; and 3) increasing the proportion of F1 hybrids in the population could significantly increase the power to detect dominance-related effects, and slightly reduce the power to detect additive and additive-by-additive effects. Analyses of cotton and rapeseed datasets showed that more additive-by-additive QTL were detected from GCA than from trait phenotype, and fewer QTL were from MPH than from other dependent variables

The Second NASA Formal Methods Workshop 1992

The primary goal of the workshop was to bring together formal methods researchers and aerospace industry engineers to investigate new opportunities for applying formal methods to aerospace problems. The first part of the workshop was tutorial in nature. The second part of the workshop explored the potential of formal methods to address current aerospace design and verification problems. The third part of the workshop involved on-line demonstrations of state-of-the-art formal verification tools. Also, a detailed survey was filled in by the attendees; the results of the survey are compiled