Engineering Research and Applications
|Pre-Milestone A and Early-Phase Systems Engineering: A Retrospective Review and Benefits for Future Air Force Acquisition
The ability of U.S. military forces to field new weapons systems quickly and to contain their cost growth has declined significantly over the past few decades. There are many causes including increased complexity, funding instability, bureaucracy, and more diverse user demands, but a view that is gaining more acceptance is that better systems engineering (SE) could help shorten development time. To investigate this assertion in more detail, the US Air Force asked the NRC to examine the role that SE can play during the acquisition life cycle to address root causes of program failure especially during pre-milestone A and early program phases. This book presents an assessment of the relationship between SE and program outcome; an examination of the SE workforce; and an analysis of SE functions and guidelines. The latter includes a definition of the minimum set of SE processes that need to be accounted for during project development.
|Summary of a Workshop for Software-Intensive Systems and Uncertainty at Scale
The growing scale and complexity of software-intensive systems are introducing fundamental new challenges of uncertainty and scale that are particularly demanding for defense systems. To assist in meeting these challenges, the Department of Defense asked the NRC to assess the nature of U.S. national investment in software research. As part of this study, a workshop was held to examine uncertainty at scale in current and future software-intensive systems. This report presents a summary of the workshop discussions that centered on process, architecture, and the grand scale; DoD software challenges for future systems; agility at scale; quality and assurance with scale and uncertainty; and enterprise scale and beyond. The report also offers a summary of key themes emerging from the workshop: architectural challenges in large-scale systems; the need for software engineering capability; and open questions and research opportunities.
|Proceedings of the Materials Forum 2007: Corrosion Education for the 21st Century
The U.S. industrial complex and its associated infrastructure are essential to the nation's quality of life, its industrial productivity, international competitiveness, and security. Each component of the infrastructure—such as highways, airports, water supply, waste treatment, energy supply, and power generation—represents a complex system requiring significant investment. Within that infrastructure both the private and government sectors have equipment and facilities that are subject to degradation by corrosion, which significantly reduces the lifetime, reliability, and functionality of structures and equipment, while also threatening human safety. The direct costs of corrosion to the U.S. economy represent 3.2 percent of the gross domestic product (GDP), and the total costs to society can be twice that or greater. Opportunities for savings through improved corrosion control exist in every economic sector. The workshop, Corrosion Education for the 21st Century, brought together corrosion specialists, leaders in materials and engineering education, government officials, and other interested parties. The workshop was also attended by members of NRC's Committee on Assessing Corrosion Education, who are carrying out a study on this topic. The workshop panelists and speakers were asked to give their personal perspectives on whether corrosion abatement is adequately addressed in our nation's engineering curricula and, if not, what issues need to be addressed to develop a comprehensive corrosion curriculum in undergraduate engineering. This proceedings consists of extended abstracts from the workshop's speakers that reflect their personal views as presented to the meeting. Proceedings of the Materials Forum 2007: Corrosion Education for the 21st Century summarizes this form.
|Software for Dependable Systems: Sufficient Evidence?
The focus of Software for Dependable Systems is a set of fundamental principles that underlie software system dependability and that suggest a different approach to the development and assessment of dependable software. Unfortunately, it is difficult to assess the dependability of software. The field of software engineering suffers from a pervasive lack of evidence about the incidence and severity of software failures; about the dependability of existing software systems; about the efficacy of existing and proposed development methods; about the benefits of certification schemes; and so on. There are many anecdotal reports, which—although often useful for indicating areas of concern or highlighting promising avenues of research—do little to establish a sound and complete basis for making policy decisions regarding dependability. The committee regards claims of extraordinary dependability that are sometimes made on this basis for the most critical of systems as unsubstantiated, and perhaps irresponsible. This difficulty regarding the lack of evidence for system dependability leads to two conclusions: (1) that better evidence is needed, so that approaches aimed at improving the dependability of software can be objectively assessed, and (2) that, for now, the pursuit of dependability in software systems should focus on the construction and evaluation of evidence. The committee also recognized the importance of adopting the practices that are already known and used by the best developers; this report gives a sample of such practices. Some of these (such as systematic configuration management and automated regression testing) are relatively easy to adopt; others (such as constructing hazard analyses and threat models, exploiting formal notations when appropriate, and applying static analysis to code) will require new training for many developers. However valuable, though, these practices are in themselves no silver bullet, and new techniques and methods will be required in order to build future software systems to the level of dependability that will be required.
|Assessment of the Results of External Independent Reviews for U.S. Department of Energy Projects
Peer review is an essential component of engineering practice and other scientific and technical undertakings. Peer reviews are conducted to ensure that activities are technically adequate, competently performed, and properly documented; to validate assumptions, calculations, and extrapolations; and to assess alternative interpretations, methodologies, acceptance criteria, and other aspects of the work products and the documentation that support them. Effective peer reviews are conducted in an environment of mutual respect, recognizing the contributions of all participants. Their primary objective is to help the project team achieve its goals. Reviews also contribute to quality assurance, risk management, and overall improvement of the management process. The U.S. Department of Energy (DOE) conducts different types of peer reviews at the different stages of a project, including reviews to assess risks and other factors related to design, safety, cost estimates, value engineering, and project management. Independent project reviews (IPRs) are conducted by federal staff not directly affiliated with the project or program and management and operations (M&O) contractors. External independent reviews (EIRs) are overseen by the Office of Engineering and Construction Management and conducted by contractors external to the department. EIRs are the primary focus of this report. However, the committee found that, in many cases, IPRs are explicitly used as preparation for or as preliminary reviews prior to EIRs. Thus, because IPRs are integral to the review process in DOE, they are also discussed because they might have an effect on EIRs. In October 2000, DOE issued Order 413.3, Program and Project Management for the Acquisition of Capital Assets (DOE, 2000). The order established a series of five critical decisions (CDs), or major milestones, that require senior management review and approval to ensure that a project satisfies applicable mission, design, security, and safety requirements: approve mission need, approve alternative selection and cost range, approve performance baseline, approve start of construction, and approve start of operations or project closeout. Assessment of the Results of External Independent Reviews for U. S. Department of Energy Projects summarizes the results.
|Assessment of Millimeter-Wave and Terahertz Technology for Detection and Identification of Concealed Explosives and Weapons
The security of the U.S. commercial aviation system has been a growing concern since the 1970's when the hijacking of aircraft became a serious problem. Over that period, federal aviation officials have been searching for more effective ways for non-invasive screening of passengers, luggage, and cargo to detect concealed explosives and weapons. To assist in this effort, the Transportation Security Administration (TSA) asked the NRC for a study of emerging screening technologies. This report--the third of four--focuses on currently maturing millimeter-wavelength/terahertz imaging and spectroscopy technologies that offer promise in meeting aviation security requirements. The report provides a description of the basic operation of these imaging systems, an assessment of their component technologies, an analysis of various system concepts, and an implementation strategy for deployment of millimeter-wavelength/terahertz technology screening systems.