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Azad M. Madni

Bio: Azad M. Madni is an academic researcher from University of Southern California. The author has contributed to research in topics: Resilience (network) & System of systems. The author has an hindex of 22, co-authored 152 publications receiving 2151 citations. Previous affiliations of Azad M. Madni include Massachusetts Institute of Technology.


Papers
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Journal ArticleDOI
TL;DR: This paper defines resilience from different perspectives, provides a conceptual framework for understanding and analyzing disruptions, and presents principles and heuristics based on lessons learned that can be employed to build resilient systems.
Abstract: As systems continue to grow in size and complexity, they pose increasingly greater safety and risk management challenges. Today when complex systems fail and mishaps occur, there is an initial tendency to attribute the failure to human error. Yet research has repeatedly shown that more often than not it is not human error but organizational factors that set up adverse conditions that increase the likelihood of system failure. Resilience engineering is concerned with building systems that are able to circumvent accidents through anticipation, survive disruptions through recovery, and grow through adaptation. This paper defines resilience from different perspectives, provides a conceptual framework for understanding and analyzing disruptions, and presents principles and heuristics based on lessons learned that can be employed to build resilient systems.

477 citations

Journal ArticleDOI
30 Jan 2019-System
TL;DR: The paper discusses the benefits of integrating digital twins with system simulation and Internet of Things (IoT) in support of MBSE and provides specific examples of the use and benefits of digital twin technology in different industries.

433 citations

Journal ArticleDOI
TL;DR: The motivation for MBSE, its current state of maturity, and systems modeling methodologies and the role of ontologies and metamodels in MBSe are discussed.
Abstract: As systems continue to grow in scale and complexity, the Systems Engineering community has turned to Model‐Based Systems Engineering (MBSE) to manage complexity, maintain consistency, and assure traceability during system development. It is different from “engineering with models,” which has been a common practice in the engineering profession for decades. MBSE is a holistic, systems engineering approach centered on the evolving system model, which serves as the “sole source of truth” about the system. It comprises system specification, design, validation, and configuration management. Even though MBSE is beginning to see a fair amount of use in multiple industries, specific advances are needed on multiple fronts to realize its full benefits. This paper discusses the motivation for MBSE, and its current state of maturity. It presents systems modeling methodologies and the role of ontologies and metamodels in MBSE. It presents model‐based verification and validation (V&V) as an example of MBSE use. An illustrative example of the use of MBSE for design synthesis is presented to demonstrate an important MBSE capability. The paper concludes with a discussion of challenges to widescale adoption and offers promising research directions to fully realize the potential benefits of MBSE.

171 citations

Journal ArticleDOI
TL;DR: The properties and tradeoffs for engineered resilient systems in the military context are explored and promising research themes that need to be pursued by the research community to help the DoD realize the vision of affordable, adaptable, and effective systems are presented.

86 citations

Journal ArticleDOI
TL;DR: How advances in computational technology can potentially transform the system development process in new and novel ways to enable fast, efficient, and inexpensive upfront engineering—the key to engineering resilient systems is presented.
Abstract: Resilience means different things in different disciplines. From a systems engineering perspective, we define resilience as the ability of a system to adapt affordably and perform effectively across a wide range of operational contexts, where context is defined by mission, environment, threat, and force disposition. A key issue in engineering resilient systems is the lengthy and costly upfront engineering process, which program managers justifiably find unacceptable. This paper presents how advances in computational technology can potentially transform the system development process in new and novel ways to enable fast, efficient, and inexpensive upfront engineering—the key to engineering resilient systems. These processes, in turn, can enable rapid development, deployment, and operation of affordably adaptable and effective systems. ©2012 Wiley Periodicals, Inc. Syst Eng 16

83 citations


Cited by
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Book ChapterDOI
TL;DR: In this article, the results of a multi-year research program to identify the factors associated with variations in subjective workload within and between different types of tasks are reviewed, including task-, behavior-, and subject-related correlates of subjective workload experiences.
Abstract: The results of a multi-year research program to identify the factors associated with variations in subjective workload within and between different types of tasks are reviewed. Subjective evaluations of 10 workload-related factors were obtained from 16 different experiments. The experimental tasks included simple cognitive and manual control tasks, complex laboratory and supervisory control tasks, and aircraft simulation. Task-, behavior-, and subject-related correlates of subjective workload experiences varied as a function of difficulty manipulations within experiments, different sources of workload between experiments, and individual differences in workload definition. A multi-dimensional rating scale is proposed in which information about the magnitude and sources of six workload-related factors are combined to derive a sensitive and reliable estimate of workload.

11,418 citations

01 Mar 2001
TL;DR: Using singular value decomposition in transforming genome-wide expression data from genes x arrays space to reduced diagonalized "eigengenes" x "eigenarrays" space gives a global picture of the dynamics of gene expression, in which individual genes and arrays appear to be classified into groups of similar regulation and function, or similar cellular state and biological phenotype.
Abstract: ‡We describe the use of singular value decomposition in transforming genome-wide expression data from genes 3 arrays space to reduced diagonalized ‘‘eigengenes’’ 3 ‘‘eigenarrays’’ space, where the eigengenes (or eigenarrays) are unique orthonormal superpositions of the genes (or arrays). Normalizing the data by filtering out the eigengenes (and eigenarrays) that are inferred to represent noise or experimental artifacts enables meaningful comparison of the expression of different genes across different arrays in different experiments. Sorting the data according to the eigengenes and eigenarrays gives a global picture of the dynamics of gene expression, in which individual genes and arrays appear to be classified into groups of similar regulation and function, or similar cellular state and biological phenotype, respectively. After normalization and sorting, the significant eigengenes and eigenarrays can be associated with observed genome-wide effects of regulators, or with measured samples, in which these regulators are overactive or underactive, respectively.

1,815 citations

Journal Article
TL;DR: The World is Flat: A Brief History of the Twenty-First Century Thomas L. Friedman Farrar, Straus and Giroux, 2005 Thomas Friedman is a widely-acclaimed journalist, foreign affairs columnist for the New York Times, and author of four best-selling books that include From Beirut to Jerusalem (1989) as mentioned in this paper.
Abstract: The World is Flat: A Brief History of the Twenty-First Century Thomas L. Friedman Farrar, Straus and Giroux, 2005 Thomas Friedman is a widely-acclaimed journalist, foreign affairs columnist for the New York Times, and author of four best-selling books that include From Beirut to Jerusalem (1989). His eminence as a journalist is clearly demonstrated in the way he prepared for The World is Flat. He traveled throughout the world, interviewing in depth the political and business leaders who have the most direct, hands-on knowledge of the truly incredible developments occurring in the business structures and technology of globalization. Only a journalist who moves freely at the highest levels could interview the likes of Sir John Rose, the chief executive of Rolls-Royce; Nobuyuki Idei, the chairman of Sony; Richard Koo, the chief economist for the Nomura Research Institute; Bill Gates of Microsoft; Wee Theng Tan, the president of Intel China; David Baltimore, president of Caltech; Howard Schultz, founder and chairman of Starbucks; Nandan Nilekani, CEO of Infosys in Bangalore - and many others, each of whom gave him the inside story of how, specifically, the barriers of time and space separating economies, workforces, sources of capital, and technical abilities are crumbling. The result of this unfolding story, already far along but with much farther to go, according to Friedman, is that "the world is flat." With some notable exceptions in sub-Saharan Africa and the Islamic swathe, everything is connected with everything else on a horizontal basis, with distance and erstwhile time-lags no longer mattering. Friedman describes in detail the galloping globalization that has unfolded in even so limited a time as the past five years. Under the impetus of a worldwide network of interconnectivity, the world economy is much-changed from what it was at the turn of the century a mere half-decade ago. Friedman quotes the CEO of India's Infosys: "What happened over the last [few] years is that there was a massive investment in technology, especially in the bubble era, when hundreds of millions of dollars were invested in putting broadband connectivity around the world, undersea cables," while (Friedman paraphrases him) "computers became cheaper and dispersed all over the world, and there was an explosion of software - e-mail, search engines like Google, and proprietary software that can chop up any piece of work and send one part to Boston, one part to Bangalore, and one part to Beijing...." Microprocessors today have 410 million transistors compared to the 2800 they had in 1971. And now, "wireless is what will allow you to take everything that has been digitized, made virtual and personal, and do it from anywhere." The effect on productivity is revolutionary: "It now takes Boeing eleven days to build a 737, down from twenty-eight days just a few years ago. Boeing will build the next generation of planes in three days, because all the parts are computer-designed for assembly." The most strikingly informative aspect of this book, however, is not about technology. Most especially, Friedman explores the rapidly evolving global business systems, each constantly regenerating itself to keep ahead of the others. These are systems that span the continents seeking the lowest-cost providers of everything from expert scientific and engineering work to the lowliest grunt work. Friedman points out that India produces 70,000 accounting graduates each year - and that they are willing to start at $100 a month. It is no wonder that Boeing employs 800 Russian scientists and engineers for passenger-plane design when "a U.S. aeronautical engineer costs $120 per design hour, a Russian costs about one-third of that." Friedman describes a call center in India where outbound callers sell "everything from credit cards to phone minutes," while operators taking inbound calls do "everything from tracing lost luggage for U.S. and European airline passengers to solving computer problems for confused American consumers. …

1,639 citations

Journal ArticleDOI
TL;DR: This survey addresses the subject of bilateral teleoperation, a research stream with more than 50 years of history and one that continues to be a fertile ground for theoretical exploration and many applications.

1,584 citations

Journal ArticleDOI
TL;DR: This paper presents a review of recent research articles related to defining and quantifying resilience in various disciplines, with a focus on engineering systems and provides a classification scheme to the approaches, focusing on qualitative and quantitative approaches and their subcategories.

1,072 citations