SUMMARY This paper is concerned with the correct specification and validation of quality attribute requirements (QARs) that crosscut through a diverse set of complex system functions. These requirements act as modifiers of system level functional requirements and thus have substantial influence on the eventual architectural selection. Because system designers traditionally address these requirements one quality attribute at a time, the process frequently results in QARs that contain subtle conflicting behaviors. This paper presents an approach to QAR‐induced behavior validation and conflict detection via execution‐based model checking early in the software development process. It explores the concept of conflicts between requirements with temporal and sequencing behaviors and presents an automated approach for discovering such conflicts. Published 2012. This article is a US Government work and is in the public domain in the USA.

This paper discusses the use of social media and cloud computing technologies to facilitate the collaboration and communication in enterprise-wide workflow processes. It presents a use case analysis of the US Army Test and Evaluation Command (ATEC) test program management to demonstrate how cloud computing and social media could streamline pre-existing, highly serialized, enterprise-wide workflow processes. The resulting optimizations to the monitoring, reporting, and control aspects will lead to situational awareness information being available to senior leadership with far fewer intermediary, human-in-the-loop steps. These optimizations, when combined with social networking tools and a common integrated working environment for program artifacts, may result in an increase to productivity across all levels of the organization.

During disaster response, key resources are supplied from a variety of channels including: government agencies, volunteer organizations, commercial businesses, educational institutions and others. While these entities have efficient internal methods of communication and coordination, interorganizational collaboration has often been hindered by political, social, and technological challenges. This paper examines the challenges to collaboration among responding entities and proposes a technology-enabled self-synchronization framework for sharing information using a distributed, highly scalable, web application based on the cloud computing technologies. The proposed design applies the unique benefits of cloud computing to the disaster response domain. This notional design facilitates communication among a broad range of public and private groups without requiring these organizations to compromise competitive advantage.

This paper presents some concepts, principles, and techniques for automated testing of system-of-systems based on attributed event grammar (AEG) modeling of the system's operational environment. AEG provides a uniform approach for automatically generating, executing, and analyzing tests. Quantitative and qualitative software risk assessment can be performed based on statistics gathered during automatic test execution within the specified environment model.

Studies have suggested that formal specifications and lightweight formal methods help improve the clarity and precision of the requirements specification. This paper describes a process to augment the current informal approaches to system-of-systems development by introducing temporal assertions to capture the safety-critical and mission-essential system requirements and runtime model checking to evaluate the system designs and implementation. The process allows users to develop and validate temporal assertions iteratively via simulation with multiple scenarios, and to use the assertions to automate the testing of the system-of-systems under development as well as armor-plating the target system against any unexpected behaviors at runtime.

Abstract The general rectilinear Steiner tree problem has been proved to be NP‐complete. In this paper, we consider a special case in which the points lie on the boundary of a rectilinear rectangle and give anO(n)algorithm to construct a minimum rectilinear Steiner tree for such points.

Abstract Based on the probabilistic approach introduced by Karp [14], we present two partitioning algorithms for the approximate solution of large instances of the rectilinear Steiner problem in the plane. The algorithms subdivide a set of given points into small groups, construct a minimum rectilinear Steiner tree for each small group, and then patch the subtrees together to form a near‐optimum rectilinear Steiner tree for the given points. Suppose there are n given points, uniformly distributed over the unit square [0,1] × [0,1] and spanned by a minimum rectilinear Steiner tree To. Then for any given integer t > 0, the first algorithm runs in O(f(t)n + n log n) time and produces a rectilinear Steiner tree T1 such that \documentclass{article}\pagestyle{empty}\begin{document}$ \left({|T_1 |/|T_0 |} \right) \le 1 + O\left({\sqrt {1/t}} \right) $\end{document} with probability approaching 1 as n → ∞, while the second algorithm has an expected running time of O(g(t)n) and it also produces a rectilinear Steiner tree T2 such that \documentclass{article}\pagestyle{empty}\begin{document}$ \left({|T_2 |/|T_0 |} \right) \le 1 + O\left({\sqrt {1/t}} \right) $\end{document} with probability approaching 1 as n → ∞.

This paper considers the computation of matrix chain products of the form $M_1 \times M_2 \times \cdots \times M_{n - 1} $. If the matrices are of different dimensions, the order in which the matrices are computed affects the number of operations. An optimum order is an order which minimizes the total number of operations. Some theorems about an optimum order of computing the matrices have been presented in Part I [SIAM J. Comput., 11 (1982), pp. 362–373]. Based on those theorems, an $O(n\log n)$ algorithm for finding the optimum order is presented here.

This paper considers the computation of matrix chain products of the form $M_1 \times M_2 \times \cdots \times M_{n - 1} $. If the matrices are of different dimensions, the order in which the product is computed affects the number of operations. An optimum order is an order which minimizes the total number of operations. We present some theorems about an optimum order of computing the matrices. Based on these theorems, an $O(n\log n)$ algorithm for finding an optimum order will be presented in Part II.

This paper considers the computation of matrix chain products of the form M1 × M2 ×...× Mn-1. If the matrices are of different dimensions, the order in which the matrices are computed affects the number of operations. An optimum order is an order which minimizes the total number of operations. We present some theorems about an optimum order of computing the matrices. Based on these theorems, an O(n log n) algorithm for finding the optimum order is presented.