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Analog coupled oscillator based weighted Ising machine

October 15, 2019
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Journal Article
Author:
Jeffrey B. Chou
…
Published in:
Sci. Rep., Vol. 9, No. 1, 15 October 2019, 14786.
Topic:
computing
R&D area:
R&D group:

Summary

We report on an analog computing system with coupled non-linear oscillators which is capable of solving complex combinatorial optimization problems using the weighted Ising model. The circuit is composed of a fully-connected 4-node LC oscillator network with low-cost electronic components and compatible with traditional integrated circuit technologies. We present the theoretical modeling, experimental characterization, and statistical analysis our system, demonstrating single-run ground state accuracies of 98% on randomized MAX-CUT problem sets with binary weights and 84% with 5-bit weight resolutions. Solutions are obtained within 5 oscillator cycles, and the time-to-solution has been demonstrated to scale directly with oscillator frequency. We present scaling analysis which suggests that large coupled oscillator networks may be used to solve computationally intensive problems faster and more efficiently than conventional algorithms. The proof-of-concept system presented here provides the foundation for realizing such larger scale systems using existing hardware technologies and could pave the way towards an entirely novel computing paradigm.
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Summary

We report on an analog computing system with coupled non-linear oscillators which is capable of solving complex combinatorial optimization problems using the weighted Ising model. The circuit is composed of a fully-connected 4-node LC oscillator network with low-cost electronic components and compatible with traditional integrated circuit technologies. We present the...

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Analog coupled oscillator based weighted Ising machine

Multi-Objective Graph Matching via Signal Filtering

October 11, 2019
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Journal Article
Author:
Daniel L. Sussman
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Published in:
IEEE Signal Processing Magazine Special Issue on GSP [submitted]
Topic:
graph processing
R&D area:
R&D group:

Summary

In this white paper we propose a new method which exploits tools from graph signal processing to solve the graph matching problem, the problem of estimating the correspondence between the vertex sets of two graphs. We recast the graph matching problem as matching multiple similarity matrices where the similarities are computed between filtered signals unique to eachnode. Using appropriate graph filters, these similarity matrices can emphasize long or short range behavior and the method will implicitly search for similarities between the graphs and at multiple scales. Our method shows substantial improvementsover standard methods which use the raw adjacency matrices, especially in low-information environments.
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Summary

In this white paper we propose a new method which exploits tools from graph signal processing to solve the graph matching problem, the problem of estimating the correspondence between the vertex sets of two graphs. We recast the graph matching problem as matching multiple similarity matrices where the similarities are...

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Multi-Objective Graph Matching via Signal Filtering

An Eye on the Storm: Tracking Power Outages via the Internet of Things

October 4, 2019
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Conference Paper
Author:
Kendra J. Kratkiewicz
Published in:
Grace Hopper Celebration 2019 [submitted]
Topic:
microgrids
R&D area:
R&D group:

Summary

Assessing the extent of power outages in the wake of disasters is a crucial but daunting challenge. We developed a prototype to estimate and map the severity and location of power outages throughout an event by taking advantage of IoT as a non-traditional power-sensing network. We present results used by FEMA and other responders during multiple major hurricanes, such as Harvey, Irma, and Maria.
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Summary

Assessing the extent of power outages in the wake of disasters is a crucial but daunting challenge. We developed a prototype to estimate and map the severity and location of power outages throughout an event by taking advantage of IoT as a non-traditional power-sensing network. We present results used by...

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An Eye on the Storm: Tracking Power Outages via the Internet of Things

Design, simulation, and fabrication of three-dimensional microsystem components using grayscale photolithography

October 1, 2019
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Journal Article
Author:
Melissa A. Smith
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Published in:
J. Micro/Nanolith., Vol. 18, No. 4, October - December 2019, 043507.
Topic:
lithography
R&D area:
R&D group:

Summary

Grayscale lithography is a widely known but underutilized microfabrication technique for creating three-dimensional (3-D) microstructures in photoresist. One of the hurdles for its widespread use is that developing the grayscale photolithography masks can be time-consuming and costly since it often requires an iterative process, especially for complex geometries. We discuss the use of PROLITH, a lithography simulation tool, to predict 3-D photoresist profiles from grayscale mask designs. Several examples of optical microsystems and microelectromechanical systems where PROLITH was used to validate the mask design prior to implementation in the microfabrication process are presented. In all examples, PROLITH was able to accurately and quantitatively predict resist profiles, which reduced both design time and the number of trial photomasks, effectively reducing the cost of component fabrication.
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Summary

Grayscale lithography is a widely known but underutilized microfabrication technique for creating three-dimensional (3-D) microstructures in photoresist. One of the hurdles for its widespread use is that developing the grayscale photolithography masks can be time-consuming and costly since it often requires an iterative process, especially for complex geometries. We discuss...

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Design, simulation, and fabrication of three-dimensional microsystem components using grayscale photolithography

Uncovering human trafficking networks through text analysis

October 1, 2019
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Conference Paper
Author:
Lin Li
Published in:
2019 Grace Hopper Celebration, 1-4 October 2019.
Topic:
algorithms
R&D area:
R&D group:

Summary

Human trafficking is a form of modern-day slavery affecting an estimated 40 million victims worldwide, primarily through the commercial sexual exploitation of women and children. In the last decade, the advertising of victims has moved from the streets to websites on the Internet, providing greater efficiency and anonymity for sex traffickers. This shift has allowed traffickers to list their victims in multiple geographic areas simultaneously, while also improving operational security by using multiple methods of electronic communication with buyers; complicating the ability of law enforcement to disrupt these illicit organizations. In this presentation, we present a novel unsupervised template matching algorithm for analyzing and detecting complex organizations operating on adult service websites. We apply this method to a large corpus of adult service advertisements retrieved from backpage.com, and show that the networks identified through the algorithm match well with surrogate truth data derived from phone number networks in the same corpus. Further exploration of the results show that the proposed method provides deeper insights into the complex structures of sex trafficking organizations, not possible through networks derived from phone numbers alone. This method provides a powerful new capability for law enforcement to more completely identify and gather evidence about trafficking operations
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Summary

Human trafficking is a form of modern-day slavery affecting an estimated 40 million victims worldwide, primarily through the commercial sexual exploitation of women and children. In the last decade, the advertising of victims has moved from the streets to websites on the Internet, providing greater efficiency and anonymity for sex...

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Uncovering human trafficking networks through text analysis

Large scale parallelization using file-based communications

September 24, 2019
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Conference Paper
Author:
Chansup Byun
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Published in:
2019 IEEE High Performance Computing Conf., HPEC, 24-26 September 2019.
Topic:
high performance computing
R&D area:
R&D group:

Summary

In this paper, we present a novel and new file-based communication architecture using the local filesystem for large scale parallelization. This new approach eliminates the issues with filesystem overload and resource contention when using the central filesystem for large parallel jobs. The new approach incurs additional overhead due to inter-node message file transfers when both the sending and receiving processes are not on the same node. However, even with this additional overhead cost, its benefits are far greater for the overall cluster operation in addition to the performance enhancement in message communications for large scale parallel jobs. For example, when running a 2048-process parallel job, it achieved about 34 times better performance with MPI_Bcast() when using the local filesystem. Furthermore, since the security for transferring message files is handled entirely by using the secure copy protocol (scp) and the file system permissions, no additional security measures or ports are required other than those that are typically required on an HPC system.
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Summary

In this paper, we present a novel and new file-based communication architecture using the local filesystem for large scale parallelization. This new approach eliminates the issues with filesystem overload and resource contention when using the central filesystem for large parallel jobs. The new approach incurs additional overhead due to inter-node...

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Large scale parallelization using file-based communications

Hypersparse neural network analysis of large-scale internet traffic

September 24, 2019
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Conference Paper
Author:
Jeremy Kepner
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Published in:
IEEE High Performance Extreme Computing Conf., HPEC, 24-26 September 2019.
Topic:
high performance computing
R&D area:
R&D group:

Summary

The Internet is transforming our society, necessitating a quantitative understanding of Internet traffic. Our team collects and curates the largest publicly available Internet traffic data containing 50 billion packets. Utilizing a novel hypersparse neural network analysis of "video" streams of this traffic using 10,000 processors in the MIT SuperCloud reveals a new phenomena: the importance of otherwise unseen leaf nodes and isolated links in Internet traffic. Our neural network approach further shows that a two-parameter modified Zipf-Mandelbrot distribution accurately describes a wide variety of source/destination statistics on moving sample windows ranging from 100,000 to 100,000,000 packets over collections that span years and continents. The inferred model parameters distinguish different network streams and the model leaf parameter strongly correlates with the fraction of the traffic in different underlying network topologies. The hypersparse neural network pipeline is highly adaptable and different network statistics and training models can be incorporated with simple changes to the image filter functions.
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Summary

The Internet is transforming our society, necessitating a quantitative understanding of Internet traffic. Our team collects and curates the largest publicly available Internet traffic data containing 50 billion packets. Utilizing a novel hypersparse neural network analysis of "video" streams of this traffic using 10,000 processors in the MIT SuperCloud reveals...

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Hypersparse neural network analysis of large-scale internet traffic

Security Design of Mission-Critical Embedded Systems

September 24, 2019
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Abstract
Author:
Mankuan Michael Vai
Published in:
HPEC 2019: IEEE Conf. on High Performance Extreme Computing, 22-24 September 2019.
Topic:
resilient systems
R&D area:
R&D group:

Summary

This tutorial explains a systematic approach of co-designing functionality and security into mission-criticalembedded systems. The tutorial starts by reviewing common issues in embedded applications to define mission objectives,threat models, and security/resilience goals. We then introduce an overview of security technologies toachieve goals of confidentiality, integrity, and availability given design criteria and a realistic threatmodel. The technologies range from practical cryptography and key management, protection of data atrest, data in transit, and data in use, and tamper resistance.A major portion of the tutorial is dedicated to exploring the mission critical embedded system solutionspace. We discuss the search for security vulnerabilities (red teaming) and the search for solutions (blueteaming). Besides the lecture, attendees, under instructor guidance, will perform realistic andmeaningful hands-on exercises of defining mission and security objectives, assessing principal issues,applying technologies, and understanding their interactions. The instructor will provide an exampleapplication (distributed sensing, communicating, and computing) to be used in these exercises.Attendees could also bring their own applications for the exercises.Attendees are encouraged to work collaboratively throughout the development process, thus creatingopportunities to learn from each other. During the exercise, attendees will consider the use of varioussecurity/resilience features, articulate and justify the use of resources, and assess the system’ssuitability for mission assurance. Attendees can expect to gain valuable insight and experience in thesubject after completing the lecture and exercises.The instructor, who is an expert and practitioner in the field, will offer insight, advice, and concreteexamples and discussions. The tutorial draws from the instructor’s decades of experience in secure,resilient systems and technology.
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Summary

This tutorial explains a systematic approach of co-designing functionality and security into mission-criticalembedded systems. The tutorial starts by reviewing common issues in embedded applications to define mission objectives,threat models, and security/resilience goals. We then introduce an overview of security technologies toachieve goals of confidentiality, integrity, and availability given design criteria...

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Security Design of Mission-Critical Embedded Systems

Introducing DyMonDS-as-a-Service (DyMaaS) for Internet of Things

September 24, 2019
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Conference Paper
Author:
Marija Ilic
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Published in:
2019 IEEE High Performance Computing Conf., HPEC, 24-26 September 2019.
Topic:
modeling
R&D area:
R&D group:

Summary

With recent trends in computation and communication architecture, it is becoming possible to simulate complex networked dynamical systems by employing high-fidelity models. The inherent spatial and temporal complexity of these systems, however, still acts as a roadblock. It is thus desirable to have adaptive platform design facilitating zooming-in and out of the models to emulate time-evolution of processes at a desired spatial and temporal granularity. In this paper, we propose new computing and networking abstractions, that can embrace physical dynamics and computations in a unified manner, by taking advantage of the inherent structure. We further design multi-rate numerical methods that can be implemented by computing architectures to facilitate adaptive zooming-in and out of the models spanning multiple spatial and temporal layers. These methods are all embedded in a platform called Dynamic Monitoring and Decision Systems (DyMonDS). We introduce a new service model of cloud computing called DyMonDS-as-a-Service (DyMaas), for use by operators at various spatial granularities to efficiently emulate the interconnection of IoT devices. The usage of this platform is described in the context of an electric microgrid system emulation.
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Summary

With recent trends in computation and communication architecture, it is becoming possible to simulate complex networked dynamical systems by employing high-fidelity models. The inherent spatial and temporal complexity of these systems, however, still acts as a roadblock. It is thus desirable to have adaptive platform design facilitating zooming-in and out...

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Introducing DyMonDS-as-a-Service (DyMaaS) for Internet of Things

Streaming 1.9 billion hyperspace network updates per second with D4M

September 24, 2019
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Conference Paper
Author:
Jeremy Kepner
…
Published in:
2019 IEEE High Performance Computing Conf., HPEC, 24-26 September 2019.
Topic:
high performance computing
R&D area:
R&D group:

Summary

The Dynamic Distributed Dimensional Data Model (D4M) library implements associative arrays in a variety of languages (Python, Julia, and Matlab/Octave) and provides a lightweight in-memory database implementation of hypersparse arrays that are ideal for analyzing many types of network data. D4M relies on associative arrays which combine properties of spreadsheets, databases, matrices, graphs, and networks, while providing rigorous mathematical guarantees, such as linearity. Streaming updates of D4M associative arrays put enormous pressure on the memory hierarchy. This work describes the design and performance optimization of an implementation of hierarchical associative arrays that reduces memory pressure and dramatically increases the update rate into an associative array. The parameters of hierarchical associative arrays rely on controlling the number of entries in each level in the hierarchy before an update is cascaded. The parameters are easily tunable to achieve optimal performance for a variety of applications. Hierarchical arrays achieve over 40,000 updates per second in a single instance. Scaling to 34,000 instances of hierarchical D4M associative arrays on 1,100 server nodes on the MIT SuperCloud achieved a sustained update rate of 1,900,000,000 updates per second. This capability allows the MIT SuperCloud to analyze extremely large streaming network data sets.
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Summary

The Dynamic Distributed Dimensional Data Model (D4M) library implements associative arrays in a variety of languages (Python, Julia, and Matlab/Octave) and provides a lightweight in-memory database implementation of hypersparse arrays that are ideal for analyzing many types of network data. D4M relies on associative arrays which combine properties of spreadsheets...

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Streaming 1.9 billion hyperspace network updates per second with D4M
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