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Analog coupled oscillator based weighted Ising machine

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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Multi-Objective Graph Matching via Signal Filtering

Author:
Published in:
IEEE Signal Processing Magazine Special Issue on GSP [submitted]

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

Published in:
Grace Hopper Celebration 2019 [submitted]

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

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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Uncovering human trafficking networks through text analysis

Author:
Published in:
2019 Grace Hopper Celebration, 1-4 October 2019.

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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Security Design of Mission-Critical Embedded Systems

Published in:
HPEC 2019: IEEE Conf. on High Performance Extreme Computing, 22-24 September 2019.

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

Author:
Published in:
2019 IEEE High Performance Computing Conf., HPEC, 24-26 September 2019.

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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Optimizing the visualization pipeline of a 3-D monitoring and management system

Published in:
2019 IEEE High Performance Computing Conf., HPEC, 24-26 September 2019.

Summary

Monitoring and managing High Performance Computing (HPC) systems and environments generate an ever growing amount of data. Making sense of this data and generating a platform where the data can be visualized for system administrators and management to proactively identify system failures or understand the state of the system requires the platform to be as efficient and scalable as the underlying database tools used to store and analyze the data. In this paper we will show how we leverage Accumulo, d4m, and Unity to generate a 3-D visualization platform to monitor and manage the Lincoln Laboratory Supercomputer systems and how we have had to retool our approach to scale with our systems.
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Summary

Monitoring and managing High Performance Computing (HPC) systems and environments generate an ever growing amount of data. Making sense of this data and generating a platform where the data can be visualized for system administrators and management to proactively identify system failures or understand the state of the system requires...

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Streaming 1.9 billion hyperspace network updates per second with D4M

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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Survey and benchmarking of machine learning accelerators

Published in:
IEEE High Performance Extreme Computing Conf., HPEC, 24-26 September 2019.

Summary

Advances in multicore processors and accelerators have opened the flood gates to greater exploration and application of machine learning techniques to a variety of applications. These advances, along with breakdowns of several trends including Moore's Law, have prompted an explosion of processors and accelerators that promise even greater computational and machine learning capabilities. These processors and accelerators are coming in many forms, from CPUs and GPUs to ASICs, FPGAs, and dataflow accelerators. This paper surveys the current state of these processors and accelerators that have been publicly announced with performance and power consumption numbers. The performance and power values are plotted on a scatter graph and a number of dimensions and observations from the trends on this plot are discussed and analyzed. For instance, there are interesting trends in the plot regarding power consumption, numerical precision, and inference versus training. We then select and benchmark two commercially-available low size, weight, and power (SWaP) accelerators as these processors are the most interesting for embedded and mobile machine learning inference applications that are most applicable to the DoD and other SWaP constrained users. We determine how they actually perform with real-world images and neural network models, compare those results to the reported performance and power consumption values and evaluate them against an Intel CPU that is used in some embedded applications.
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Summary

Advances in multicore processors and accelerators have opened the flood gates to greater exploration and application of machine learning techniques to a variety of applications. These advances, along with breakdowns of several trends including Moore's Law, have prompted an explosion of processors and accelerators that promise even greater computational and...

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