UNM Computer Science

Colloquia



Google Calendar of Colloquia

Future Colloquia (Tentative Schedule)

Info on Colloquia Requirements for Students

For students taking the colloquia course, here is some information on requirements for Spring 2012.

OS-Virtual Machine Collaboration: Improving Introspection to Bridge the Semantic Gap

Date: Friday, May 4, 2012
Time: 4:00 pm — 5:00 pm
Place: Centennial Engineering Center B146 (in the basement)

Daniela Oliveira
Bowdoin College

In the last ten years virtual machines (VMs) have been extensively used for security-related applications, such as intrusion detection systems, malicious software (malware) analyzers and secure logging and replay of system execution. A VM is high-level software designed to emulate a computer's hardware. In the traditional usage model, security solutions are placed in a VM layer, which has complete control of the system resources. The guest operating system (OS) is considered to be easily compromised by malware and runs unaware of virtualization. The cost of this approach is the semantic gap problem, which hinders the development and widespread deployment of virtualization-based security solutions: there is significant difference between the state observed by the guest OS (high level semantic information) and by the VM (low level semantic information). The guest OS works on abstractions such as processes and files, while the VM can only see lower-level abstractions, such as CPU and main memory. To obtain information about the guest OS state these virtualization solutions use a technique called introspection, by which the guest OS state is inspected from the outside (VM layer), usually by trying build a map of the OS layout to an area of memory where these solutions can analyze it. We propose a new way to perform introspection, by having the guest OS, traditionally unaware of virtualization, actively collaborate with a VM layer underneath it by requesting services and communicating data and information as equal peers in different levels of abstraction. Our approach allows for stronger and more fine-grained and flexible security approaches to be developed and it is no less secure than the traditional model, as introspection tools also depend on the OS data and code to be untampered to report correct results.

Bio:
Daniela Oliveira is an Assistant Professor in the Department of Computer Science at Bowdoin College. She received her PhD in Computer Science in 2010 from the University of California at Davis where she specialized in computer security and operating systems. Her current research focuses on employing virtual machine and operating systems collaboration to protect OS kernels against compromise. She is also interested in leveraging social trust to help distinguishing benign and malicious pieces of data. She is the recipient of the NSF CAREER Award 2012.

Geometric Shape Matching with Applications

Date: Thursday, May 3, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Carola Wenk
Associate Professor of Computer Science
University of Texas at San Antonio

Geometric shapes are at the core of a wide range of application areas. In this talk we will discuss how approaches from computational geometry can be used to solve shape matching problems arising in a variety of applications including biomedical areas and intelligent transportation systems. In particular, we will discuss point pattern matching algorithms for the comparison of 2D electrophoresis gels, as well as algorithms to compare and process trajectories for improved navigation systems and for live cell imaging.

Bio:
Carola Wenk is an Associate Professor of Computer Science at the University of Texas at San Antonio (UTSA). She received her PhD from Free University Berlin, Germany. Her research area is in algorithms and data structures, in particular geometric algorithms and shape matching. She has 40 peer-reviewed publications, 22 with students, and she is actively involved in several applied projects including topics in biomedical areas and in intelligent transportation systems. She is the principal investigator on a $1.9M NIH grant funding the Computational Systems Biology Core Facility at UTSA. Dr. Wenk won an NSF CAREER award as well as research, teaching, and service awards at UTSA. She is actively involved in service to the university, including serving as the Chair of the Faculty Senate and as the Faculty Advisor for two student organizations.

A new approach for removing the noise in Monte Carlo rendering

Date: Tuesday, May 1, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Pradeep Sen
Department of Electrical and Computer Engineering
University of New Mexico

Image synthesis is the process of generating an image from a scene description that includes geometry, material properties, and camera/light positions. This is a central problem in many applications, ranging from rendering images for movies/videogames to generating realistic environments for training and tele-presence applications. The most powerful methods for photorealistic image synthesis are based on Monte Carlo (MC) algorithms, which simulate the full physics of light transport in a scene by estimating a series of multi-dimensional integrals using a set of random point samples. Although these algorithms can produce spectacular images, they are plagued by noise at low sampling rates and therefore require long computation times (as long as a day per image) to produce acceptable results. This has made them impractical for many applications and limited their use in real production environments. Thus, solving this issue has become one of the most important open problems in image synthesis and has been the subject of extensive research for almost 30 years.

In this talk, I present a new way to think about the source of Monte Carlo noise, and propose how to identify it in an image using a small number of computed samples. To do this, we treat the rendering system as a black box and calculate the statistical dependency between the outputs and the random parameter inputs using mutual information. I then show how we can use this information with an image-space, cross-bilateral filter to remove the MC noise but preserve important scene details. This process allows us to generate images in a few minutes that are comparable to those that took hundreds of times longer to render. Furthermore, our algorithm is fully general and works for a wide range of Monte Carlo effects, including depth of field, area light sources, motion blur, and path tracing. This work opens the door to a new set of algorithms that make Monte Carlo rendering feasible for more applications.

Bio:
Pradeep Sen is an Assistant Professor in the Department of Electrical and Computer Engineering at the University of New Mexico. He received his B.S. in Computer and Electrical Engineering from Purdue University in 1996 and his M.S. in Electrical Engineering from Stanford University in 1998 in the area of electron-beam lithography. After two years at a profitable startup company which he co-founded, he joined the Stanford Graphics Lab where he received his Ph.D. in Electrical Engineering in June 2006, advised by Dr. Pat Hanrahan.

He joined the faculty at UNM in the Fall of 2006, where he founded the UNM Advanced Graphics Lab. His core research combines signal processing theory with computation and optics/light-transport analysis to address problems in computer graphics, photography, and computational image processing. He is the co-author of five ACM SIGGRAPH papers (three at UNM) and has been awarded more than $1.7 million in research funding, including an NSF CAREER award to study the application of sparse reconstruction algorithms to computer graphics and imaging. He received two best-paper awards at the Graphics Hardware conference in 2002 and 2004, and the Lawton-Ellis Award in 2009 and the Distinguished Researcher Award in 2012, both from the ECE department at UNM. Dr. Sen has also started a successful educational program at UNM, where his videogame development program is now ranked by the Princeton Review as one of the top 10 undergraduate programs in North America.

Designing Privacy Interfaces: Supporting User Understanding and Control

Date: Thursday, April 26, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Patrick Gage Kelley
Carnegie Mellon University

Users are increasingly expected to manage complex privacy settings in their normal online interactions. From shopping to social networks, users make decisions about sharing their personal information with corporations and contacts, frequently with little assistance. Current solutions require consumers to read long documents or control complex settings buried deep in management interfaces. Because these mechanisms are difficult to use and have limited expressiveness, users often have little to no effective control.

My goal is to help people cope with the shifting privacy landscape. My work explores many aspects of how users make decisions regarding privacy, while my dissertation focuses on two specific areas: online privacy policies and mobile phone application permissions. I explored consumers' current understanding of privacy in these domains, and then used that knowledge to iteratively design, build, and test more comprehensible information displays. I simplified online privacy policies through a "nutrition label" for privacy - a simple, standardized label that helps consumers compare website practices and am currently working to redesign the Android permissions display, which I have found to be incomprehensible to most users.

Bio:
Patrick Gage Kelley is a Ph.D. candidate in Computation, Organizations, and Society at Carnegie Mellon University's (CMU) School of Computer Science, who is co-advised by Lorrie Faith Cranor and Norman Sadeh. His research centers on information design, usability, and education involving privacy. He has worked on projects related to passwords, location-sharing, privacy policies, mobile apps, Twitter, Facebook relationship grouping, and the use of standardized, user-friendly privacy displays. He also works with the CMU School of Art's STUDIO for Creative Inquiry in new media arts and information visualization. For more see http://patrickgagekelley.com

Motors, Voters, and the Future of Embedded Security

Date: Tuesday, April 24, 2012
Time: 11:00 am — 12:15 pm
Place: Centennial Engineering Center 1041 (NOTE DIFFERENT LOCATION FROM USUAL LOCATION)

Stephen Checkoway
Computer Science & Engineering
University of California San Diego

The stereotypical view of computing, and hence computer security, is a landscape filled with laptops, desktops, smartphones and servers; general purpose computers in the proper sense. However, this is but the visible tip of the iceberg. In fact, most computing today is invisibly embedded into systems and environments that few of us would ever think of as computers. Indeed, applications in virtually all walks of modern life, from automobiles to medical devices, power grids to voting machines, have evolved to rely on the same substrate of general purpose microprocessors and (frequently) network connectivity that underlie our personal computers. Yet along with the power of these capabilities come the same potential risks as well. My research has focused on understanding the scope of such problems by exploring vulnerabilities in the embedded environment, how they arise, and the shape of the attack surfaces they expose. In this talk, I will particularly discuss recent work on two large-scale platforms: modern automobiles and electronic voting machines. In each case, I will explain how implicit or explicit assumptions in the design of the systems have opened them to attack. I will demonstrate these problems, concretely and completely, including arbitrary control over election results and remote tracking and control of an unmodified automobile. I will explain the nature of these problems, how they have come to arise, and the challenges in hardening such systems going forward.

Bio:
Stephen Checkoway is a Ph.D. candidate in Computer Science and Engineering at UC San Diego. Before that he received his B.S. from the University of Washington. He is also a member of the Center for Automotive Embedded Systems Security, a collaboration between UC San Diego and the University of Washington. Checkoway's research spans a range of applied security problems including the security of embedded and cyber-physical systems, electronic voting, and memory safety vulnerabilities.

Hybrid Analysis and Control of Malware

Date: Monday, April 23, 2012
Time: 3:30 pm — 4:30 pm
Place: Centennial Engineering Center 1041 (NOTE DIFFERENT LOCATION AND TIME)

Barton P. Miller
Computer Sciences Department
University of Wisconsin

Malware attacks necessitate extensive forensic analysis efforts that are manual-labor intensive because of the analysis-resistance techniques that malware authors employ. The most prevalent of these techniques are code unpacking, code overwriting, and control transfer obfuscations. We simplify the analyst's task by analyzing the code prior to its execution and by providing the ability to selectively monitor its execution. We achieve pre-execution analysis by combining static and dynamic techniques to construct control- and data-flow analyses. These analyses form the interface by which the analyst instruments the code. This interface simplifies the instrumentation task, allowing us to reduce the number of instrumented program locations by a hundred-fold relative to existing instrumentation-based methods of identifying unpacked code. We implement our techniques in SD-Dyninst and apply them to a large corpus of malware, performing analysis tasks such as code coverage tests and call-stack traversals that are greatly simplified by hybrid analysis.

Bio:
Barton P. Miller is a Professor of Computer Sciences at the University of Wisconsin, Madison. He received his B.A. degree from the University of California, San Diego in 1977, and M.S. and Ph.D. degrees in Computer Science from the University of California, Berkeley in 1980 and 1984. Professor Miller is a Fellow of the ACM.

Malware Analysis on Mobile and Commodity Computing Platforms

Date: Tuesday, April 17, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Manuel Egele
University of California, Santa Barbara

Two complementing approaches exist to analyze potentially malicious software (malware); static and dynamic analysis. Static analysis reasons about the functionality of the analyzed application by analyzing the program's code in source, binary, or any intermediate representation. In contrast, dynamic analysis monitors the execution of an application and the effects the application has on the execution environment. In this talk I will present a selection of my research in both areas -- static and dynamic analysis.

On commodity x86 computer systems the browser has become a central hub of activity and information. Hence, a plethora of malware exists that tries to access and leak the sensitive information stored in the browser's context. Accordingly, I will present the research and results form my dynamic analysis system (TQANA) targeting malicious Internet Explorer plugins. TQANA implements full system data-flow analysis to monitor the propagation of sensitive data originating from within the browser. This system successfully detects a variety of spyware components that steal sensitive data (e.g., the user's browsing history) from the browser.

In the mobile space, smartphones have become similar hubs for online communication and private data. The protection of this sensitive data is of great importance to many users. Therefore, I will demonstrate how my system (PiOS) leverages static binary analysis to detect privacy violations in applications targeted at Apple's iOS platform. PiOS automatically detects a variety of privacy breaches, such as the transmission of GPS coordinates, or leaked address books. Applications that transmit address book contents recently got in the focus of mainstream media as many popular social network applications (e.g., Path, Gowalla, or Facebook) transmit a copy of the user's address book to their backend servers. The static analysis in PiOS is also the foundation for a dynamic enforcement system that implements control-flow integrity (CFI) on the iOS platform. Thus, this system is suitable to prevent the broad range of control flow diverting attacks on the iOS platform.

Bio:
Manuel Egele currently is a post-doctoral researcher at the Computer Security Group at the Department of Computer Science of the University of California, Santa Barbara. Hereceived his Ph.D. in January 2011 from the Vienna University of Technology under his advisors Christopher Kruegel and Engin Kirda. Before starting his work as a post-doc he visited the Computer Security Group at UCSB as part of his Ph.D. studies. Similarly, he spent six months visiting the iSeclab's research lab in France (i.e., Institute Eurecom). He was very fortunate to meet and work with interesting and smart people at all these locations.

His research interests include most aspects of systems security, such as mobile security, binary and malware analysis, and web security.

Since 2009 he has helped organizing UCSB's iCTF. In 2010 they were the first CTF that featured a challenge with effects on the physical world (i.e., the teams had to control a foam missile launcher). In 2011 they took this concept one step further and teams from around the globe could remote control a unmaned areal vehicle in the conference room of UCSB's Computer Science Department. Before being part of the organzing team for the iCTF he participated as part of the We_0wn_Y0u team of the Vienna University of Technology, as well as on the team of the Institute Eurecom. Furthermore, he participated as part of the Shellphish team at several DefCon CTF competitions in Las Vegas.

Security Across the Software-Silicon Boundary

Date: Tuesday, April 10, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Mohit Tiwari
University of California, Berkeley

The synergy between computer architecture and program analysis can reveal vital insights into the design of secure systems. The ability to control information as it flows through a machine is a key primitive for computer security, however, software-only analyses are vulnerable to leaks in the underlying hardware. In my talk, I will demonstrate how complete information flow control can be achieved by co-designing an analysis together with the processor architecture.
The analysis technique, GLIFT, is based on the insight that all information flows -- whether explicit, implicit, or timing channels -- look surprisingly alike at the gate level where assembly language descriptions crystallize into precise logical functions. The architecture introduces Execution Leases, a programming model that allows a small kernel to directly control the flow of all secret or untrusted information, and whose implementation is verifiably free from all digital information leaks. In the future, my research will use this cross-cutting approach to build systems that make security and privacy accessible to mainstream users while supporting untrusted applications across cloud and client devices.

Bio:
Mohit Tiwari is a Computing Innovation Fellow at University of California, Berkeley. He received his PhD in Computer Science from University of California, Santa Barbara in 2011. His research uses computer architecture and program analyses to build secure, reliable systems, and has received a Best Paper award at PACT 2009, an IEEE Micro Top Pick in 2010, and the Outstanding Dissertation award in Computer Science at UCSB in 2011.

Coexistence, Collaboration, and Coordination Paradigms in the Presence of Mobility

Date: Thursday, April 5, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Gruia-Catalin Roman
University of New Mexico
Dean of the School of Engineering

Mobile computing is a broad field of study made possible by advances in wireless technology, device miniaturization, and innovative packaging of computing, sensing, and communication resources. This talk is intended as a personal intellectual journey spanning a decade of research activities, which have been shaped by the concern with rapid development of applications designed to operate in the fluid and dynamic settings that characterize mobile and sensor networks. The presence of mobility often leads to fundamental changes in our assumptions about the computing and communication environment and about its relation to the physical world and the user community. This, in turn, can foster a radical reassessment of one's perspective on software system design and deployment. Several paradigm shifts made manifest by considerations having to do with physical and logical mobility will be examined and illustrated by research involving formal models, algorithms, middleware, and protocols. Special emphasis will be placed on problems that entail collaboration and coordination in the mobile setting.

Bio:
Gruia-Catalin Roman was born in Bucharest, Romania, he studied general engineering topics for two years at the Polytechnic Institute of Bucharest and became the beneficiary of a Fulbright Scholarship. In the fall of 1971, Roman entered the very first computer science freshman class at the University of Pennsylvania. In the years that followed, he earned B.S. (1973), M.S. (1974), and Ph.D. (1976) degrees, all in computer science. At the age of 25, he began his academic career as Assistant Professor at Washington University in St. Louis. In 1997, Roman was appointed department head. Under his leadership, the Department of Computer Science and Engineering experienced a dramatic transformation in faculty size, level of research activities, financial strength, and reputation. In 2004, he was named the Harold B. and Adelaide G. Welge Professor of Computer Science at Washington University. On July 1, 2011, he became the 18th dean of the University of New Mexico School of Engineering. His aspirations as dean are rooted in his conviction that engineering and computing play central and critical roles in facilitating social and economic progress. Roman sees the UNM School of Engineering as being uniquely positioned to enable scientific advances, technology transfer, and workforce development on the state, national, and international arenas in ways that are responsive to both environmental and societal needs and that build on the rich history, culture, and intellectual assets of the region.

How should computers fix themselves? or Self-healing distributed networks

Date: Tuesday, April 3, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Amitabh Trehan
Technion, Haifa, Israel

Consider a simple turn based game between an attacker and a defender (you) playing on a large connected graph: In her turn, the attacker deletes a node and in your turn you are supposed to connect all the neighbors of the deleted node so that somehow at any point in the game, no node has increased its degree by more than a constant nor has the diameter of the network blown up. Now, consider that the nodes themselves are smart computers or agents and do not know anything about their network other than their 'nearby' nodes and have no centralized help; In essence they have to maintain certain local and global properties by only local actions while under attack from a powerful adversary.

The above game captures the essence of distributed self-healing in reconfigurable networks (e.g. peer-to-peer, ad-hoc and wireless mesh networks etc). Many such challenging and interesting scenarios arise in this context. We will look at some of these scenarios and at our small but rich and evolving body of work. Our algorithms simultaneously maintain a subset of network properties such as connectivity, degree, diameter, stretch, subgraph density, expansion and spectral properties. Some of our work uses the idea of virtual graphs - graphs consisting of 'virtual' nodes simulated by the real nodes, an idea that we will look at in more detail.

Bio:
Amitabh Trehan is a postdoc at Technion, Haifa, Israel. There, he works with Profs. Shay Kutten and Ron Lavi on distributed algorithms and game theory. He has earlier also worked as a postdoc with Prof. Valerie King (at UVIC, Canada). He did his Ph.D. with Prof. Jared Saia at UNM on algorithms for self-healing networks.

His broad research interests are in theory and algorithms with specific interests in distributed algorithms, networks, and game theory.His interest includes designing efficient distributed algorithms for robustness/self-healing/self-* properties in systems under adversarial attack, and studying game theoretic and other mechanisms for evolving networks, such as social networks or distributed systems (P2P networks etc).

Internet voting - threat or menace

Date: Tuesday, March 27, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Jeremy Epstein
SRI International

Internet voting is in the headlines, frequently coupled with the question "if I can bank online and shop online why can't I vote online." This presentation will describe the range of systems that fall under the name "internet voting," explain the security issues in today's internet voting systems, recommend what can and can't be done safely, discuss limitations of experimental systems, and point to future directions and areas for research.

Bio:
Jeremy Epstein is Senior Computer Scientist at SRI International in Arlington, VA where his research interests include voting systems security and software assurance. Prior to joining SRI, Jeremy led product security for an international software vendor. He's been involved with varying aspects of security for over 20 years. He is Associate Editor in Chief of IEEE Security & Privacy magazine, an organizer of the Annual Computer Security Applications Conference, and serves on too many program committees. Jeremy grew up in Albuquerque where he attended Sandia High School and UNM (part time while in high school), before fleeing the big city to earn a B.S. from New Mexico Tech in Computer Science, followed by an M.S. from Purdue University. He's lived in Virginia for 25 years, and misses green chile every day.

Using fine-grained code and fine-grained interviews to understand how electrical engineers learn to program

Date: Tuesday, March 20, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Brian Danielak
University of Maryland, College Park

Students can take remarkably different paths toward the development of design knowledge and practice. Using data from a study of an introductory programming course for electrical engineers, we investigate how students learn elements of design in the course, and how their code (and the process by which they generate it) reflects what they're learning about design. Data are coordinated across clinical interviews, ethnographic observation, and fine-grained evolution of students' code, exploring the question of what it means to "know" design practices common to programming, such as functional abstraction and hierarchical decomposition.

Bio:
Brian Danielak is currently a fourth-year Ph.D. student in Science Education Research at the University of Maryland. At the moment, he studies how university engineering students engage in mathematical and physical sensemaking in their courses. He works under Ayush Gupta, and his advisor Andy Elby. His research interests include mathematical sensemaking and symbolic reasoning, representational competency in scientific argumentation, students' epistemological beliefs in science and mathematics, and interplays of emotion, cognition, and student epistemology. He graduated from the University of Buffalo Honors Program, with degrees in Chemistry (BA, 2007) and English (BA, 2007). While there, he worked as an undergraduate research fellow with Kenneth Takeuchi. He also completed an Undergraduate Honors Thesis on the relationships between narrative and science under the direction of Robert Daly.

Principles of Scalable HPC System Design

Date: Tuesday, March 6, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Suzanne Kelly
Sandia National Lab

Sandia National Laboratories has a long history of successfully applying high performance computing (HPC) technology to solve scientific problems. We drew upon our experiences with numerous architectural and design features when planning our most recent computer systems. This talk will present the key issues that were considered. Important principles are performance balance between the hardware components and scalability of the system software. The talk will conclude with lessons learned from the system deployments.

Bio:
Suzanne Kelly is a distinguished member of technical staff at Sandia National Laboratories. Suzanne holds a BS in computer science from the University of Michigan and an MS in computer science from Boston University. Suzanne has worked on projects related to system-level software as well as information systems. In addition to her project management activities, she currently has responsibility for the system software on the Cielo supercomputer. Her previous assignments were leading the operating system teams for the Red Storm and ASCI Red supercomputers. Prior to her 6-year sojourn in information systems for nuclear defense technologies, she worked on various High Performance Computing file archive systems.

CitiSense - Always-on Participatory Sensing for Air Quality

Date: Thursday, March 1, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

William G. Griswold
Department of Computer Science & Engineering
University of California, San Diego

Recent revelations about the impact of air pollution on our health are troubling, yet air pollution and the risks it poses to us are largely invisible. Today, the infrastructure of our regulatory institutions is inadequate for the cause: sensors are few and often far from where we live. What about the air quality on your jogging route or commute? Can you be told when it matters most? Recent advances in computing technology put these capabilities within reach. By pervasively monitoring our immediate environs, aggregating the data for analysis, and reflecting the results back to us quickly, we can avoid toxic locales, appreciate the consequences of our behavior, and together seek a mandate for change. In this talk, I describe CitiSense, which leverages the proliferation of mobile phones and the advent of cheap, small sensors to develop a new kind of .citizen infrastructure.. We have built a robust end-to-end prototype system, exposing an abundance of challenges in power management, software architecture, privacy, inference with "noisy" commodity sensors, and interaction design. The most critical challenge is providing an always-on experience when depending on the personal devices of users. I report on early research results, including those of our first user study, which reveal the incredible potential for participatory sensing of air quality, but also open problems.

Bio:
William G. Griswold is a Professor of Computer Science and Engineering at UC San Diego. He received his Ph.D. in Computer Science from the University of Washington in 1991, and his BA in Mathematics from the University of Arizona in 1985. His research interests include ubiquitous computing and software engineering, and educational technology. Griswold is a pioneer in the area of software refactoring. He also built ActiveCampus, one of the early mobile location-aware systems. His current CitiSense project is investigating technologies for low-cost ubiquitous real-time air-quality sensing. He was PC Chair of SIGSOFT FSE in 2002 and PC co-Chair of ICSE in 2005. He is the current past-Chair of ACM SIGSOFT. He is a member of the ACM and the IEEE Computer Society.

Line up and wait your turn!

Date: Tuesday, February 21, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Tools for the Construction of Optimized Matrix Algebra Software

Date: Tuesday, February 28, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Elizabeth Jessup
University of Colorado
Department of Computer Science

Linear algebra constitutes the most time-consuming part of simulations in many fields of science and engineering. Reducing the costs of those calculations can have a significant impact on overall routine performance, but such optimization is difficult. At each step of the process, the code developer is confronted with many possibilities. Choosing between them generally requires expertise in numerical computation, mathematical software, compilers, and computer architecture, yet few scientists have such broad expertise. This talk will cover two interrelated collaborative projects focused on easing the production of high-performance matrix algebra software.

I will first present work in progress on a taxonomy of software that can be used to build highly-optimized matrix algebra software. The taxonomy will provide an organized anthology of software components and programming tools needed for that task. It will serve as a guide to practitioners seeking to learn what is available for their programming tasks, how to use it, and how the various parts fit together. It will build upon and improve existing collections of numerical software, adding tools for the tuning of matrix algebra computations. Our objective is to build a taxonomy that will provide all of the software needed to take a matrix algebra problem from algorithm description to a high-performance implementation.

I will then introduce one of the tuning tools to be included in the taxonomy, the Build to Order (BTO) compiler which automates loop fusion in matrix algebra kernels. This optimization serves to reduce the amount of data moved between memory and the processor. In particular, I will describe BTO's analytic memory model which accelerates the compiler by substantially reducing the number of loop fusion options processed by it. The initial draft of the model took into account traffic through the caches and TLB. I will discuss an example that motivated us to improve the accuracy of the model by adding register allocation.

Bio:
Elizabeth Jessup's research concerns the development of efficient algorithms and software for matrix algebra problems. This work began with the development of innovative memory-efficient algorithms and, more recently, has moved toward tools to aid in programming of matrix algebra software. Dr. Jessup has recently been collaborating with experts in compiler technology, focusing on compilers that create fast numerical software. Their initial focus has been on making efficient use of the memory hierarchy on a single processor but they are moving into multicore and GPU implementations. She is also interested in usability of scientific software. To that end, Dr. Jessup is working with collaborators on a tool to automate the construction of numerical software. Given a problem specification, the tool will find and tune appropriate routines for its solution.

Dr. Jessup was co-developer of an award-winning, NSF-funded undergraduate curriculum in high-performance scientific computing and have continued to work on innovative approaches to education in her field. She has also conducted research on factors that influence women's interest in computer science.

Line up and wait your turn!

Date: Tuesday, February 21, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Tom Hayes
University of New Mexico
Department of Computer Science

We have all had the experience of waiting in a line before getting our turn to do something. I will talk about some simple algorithms involving lining up, and their sometimes surprising behavior.

Bio:
Tom Hayes is an assistant professor at the University of New Mexico in the Department of Computer Science. Broadly speaking, he is interested in Theoretical Computer Science and Machine Learning. Some of his particular interests include: convergence rates for Markov chains, sampling algorithms for random combinatorial structures, and online decision-making algorithms.

Inefficient Performance, or Doing this faster by Doing things again

Date: Thursday, February 16, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Patrick Bridges
University of New Mexico
Department of Computer Science

Modern systems are becoming increasingly challenging to fully leverage, especially but not exclusively at the system software level, with parallelism and reliability becoming major challenges. Current programming techniques do not address these challenges well, relying either on complex synchronization that is hard to understand, debug, analyze, and optimize, or forcing almost complete separation between cores. In this talk, I will present a new approach to programming system software for modern machines that leverages replication and redundancy to extract performance from multi-core hardware. In addition, its use of replication as a key structuring element has the potential to provide for a more reliable system that is robust in the face of failure. I describe the approach overall, discuss its novel features, advantages, and challenges, present performance numbers from work applying this approach in the context of a network protocol stack implementation, and discuss potential directions for future work.

Bio:
Patrick Bridges is an associate professor at the University of New Mexico in the Department of Computer Science. He did his undergraduate work at Mississippi State University and received his Ph.D. from the University of Arizona in December of 2002. His research interest broadly cover operating systems and networks particularly, scaling, composition, and adaptation issues in large-scale systems. He works with collaborators at Sandia, Los Alamos, and Lawrence Berkeley National Laboratories, IBM Research, AT&T Research, and a variety of universities.

Detecting malware: traffic classification, botnets, and Facebook scams

Date: Thursday, February 9, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Michalis Faloutsos
University of California, Riverside

In this talk, we highlight two topics on security from our lab. First, we address the problem of Internet traffic classification (e.g. web, filesharing, or botnet?). We present a fundamentally different approach to classifying traffic that studies the network wide behavior by modeling the interactions of users as a graph. By contrast, most previous approaches use statistics such as packet sizes and inter-packet delays. We show how our approach gives rise to novel and powerful ways to: (a) visualize the traffic, (b) model the behavior of applications, and (c) detect abnormalities and attacks. Extending this approach, we develop ENTELECHEIA, a botnet-detection method. Tests with real data suggests that our graph-based approach is very promising.

Second, we present, MyPageKeeper, a security Facebook app, with 13K downloads, which we deployed to: (a) quantify the presence of malware on Facebook, and (b) protect end-users. We designed MyPageKeeper in a way that strikes the balance between accuracy and scalability. Our initial results are scary and interesting: (a) malware is widespread, with 49% of our users are exposed to at least one malicious post from a friend, and (b) roughly 74% of all malicious posts contain links that point back to Facebook, and thus would evade any of the current web-based filtering approaches.

Bio:
Michalis Faloutsos is a faculty member at the Computer Science Dept. at the University of California, Riverside. He got his bachelor's degree at the National Technical University of Athens and his M.Sc and Ph.D. at the University of Toronto. His interests include, Internet protocols and measurements, peer-to-peer networks, network security, BGP routing, and ad-hoc networks. With his two brothers, he co-authored the paper on power-laws of the Internet topology, which received the ACM SIGCOMM Test of Time award. His work has been supported by many NSF and military grants, for a cumulative total of more than $6 million. Several recent works have been widely cited in popular printed and electronic press such as slashdot, ACM Electronic News, USA Today, and Wired. Most recently he has focused on the classification of traffic and web-security, and co-founded a cyber-security company founded in 2008, offering services as www.stopthehacker.com, which received two SBIR grants from the National Science Foundation, and institutional funding in Dec 2011.

Risk Scoring and Future Directions

Date: Thursday, February 2, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Joseph R. Barr
Chief Scientist at ID Analytics

Part 1: ID Analytics main business is scoring applications (for credit/services) for risks including identity/ authenticity & credit. By definition an application is a vector of identity elements (SSN, Name, Address, Phone, DOB, <more>), a vector known as .SNAPD., as well as additional fields. ID Analytics process the data, extract pertinent features and calculate risk score on the fly. The entire process has a sub-second latency. At the basis of our analytics is the ID Network – a virtual graph with SNAPD-vectors as nodes. One can envision making a connection between two nodes if they share some identity element. The weight of the edge is the strength of the connection. As one can imagine various graphical parameters are the predominant inputs to our risk models. At the time I write this, the ID network has 1.5 billion nodes (corresponding to number of transactions); this of course means that the graph is too large to be stored in memory, and needless to say, how we do it is a trade secret, but I will indicate some principles behind the ideas.

Part 2: The risk ID Analytics is scoring falls under the more general rubric of consumer behavior. We are interested in the spatial / temporal aspects of our network and how it related to macroeconomic and social data including demographics, geography, housing, census, interest rates, unemployment, federal deficit, foreign balance of trade and whatnot. Under certain conditions, we will avail our data to an outside organization to participate in publishable research.

Introducing id: a labs, a research-oriented organization which promotes collaborations with academia and other research institutions.

Bio:
Joseph R. Barr is the Chief Scientist at ID Analytics (www.idanalytics.com). After a few years in academia (as Math/CS Assistant Professor at California Lutheran University,) he has spent the past 17 years in industry as a risk & consumer behavior (analytics) professional. He was awarded a Ph.D. in mathematics from the University of New Mexico on his work on graph colorings, under the direction of Professor Roger C. Entringer. His current interests include the application of statistics, machine-learning and combinatorial algorithms to risk management and consumer behavior. Joe is married, has two young children, a boy and a girl, and an older son, a software engineer at Intel.

SCR: The Scalable Checkpoint/Restart Library

Date: Thursday, January 26, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Kathryn Mohror
Lawrence Livermore National Lab

Applications running on high-performance computing systems can encounter mean times between failures on the order of hours or days. Commonly, applications tolerate failures by periodically saving their state to checkpoint files on reliable storage, typically a parallel file system. Writing these checkpoints can be expensive at large scale, taking tens of minutes to complete. To address this problem, we developed the Scalable Checkpoint/Restart library (SCR). SCR is a multi-level checkpointing library; it checkpoints to storage on the compute nodes in addition to the parallel file system. Through experiments and modeling, we show that multi-level checkpointing benefits existing systems, and we find that the benefits increase on larger systems. In particular, we developed low-cost checkpoint schemes that are 100x-1000x faster than the parallel file system and effective against 85% of our system failures. Our approach improves machine efficiency up to 35%, while reducing the load on the parallel file system by a factor of two.

Bio:
Kathryn Mohror is a Postdoctoral Research Staff Member at the Center for Applied Scientific Computing (CASC) at Lawrence Livermore National Laboratory. Kathryn.s research on high-end computing systems is currently focused on scalable fault tolerant computing and performance measurement and analysis. Her other research interests include scalable automated performance analysis and tuning, parallel file systems, and parallel programming paradigms. Kathryn received her Ph.D. in Computer Science in 2010, an M.S. in Computer Science in 2004, and a B.S. in Chemistry in 1999 from Portland State University in Portland, OR.

Graph and Structure Inference for Scientific Data Mining

Date: Thursday, January 19, 2012
Time: 11:00 am — 12:15 pm
Place: Mechanical Engineering 218

Terran Lane
UNM Department of Computer Science

Many modern scientific phenomena are best described in terms of graphs. From social networks to brain activity networks to genetic networks to information networks, attention is increasingly shifting to data that describe or originate in graph structures. But because of nonlinearities and statistical dependencies in graphical data, most "traditional" statistical methods are not well suited to such data. Coupled with the explosion of raw data, stemming from revolutions inscientific measurement equipment, domain scientists are facing steep challenges in statistical inference and data mining.

In this talk, I will describe work that my group has been doing on the identification of graph structure from indirect data. This problem is very familiar to the machine learning community, where it is known to be both computationally and statistically challenging, but has received substantially less attention in a number of scientific communities, where it is of substantial practical interest. I will examine an approach to graph structure inference that roots into the topology of graph structure space. By imposing metric structure on this otherwise unstructured set, we can develop fast, efficient, accurate inference mechanisms. I will explain our approach and illustrate the core idea and variants with examples drawn from neuroscience and genomics and introduce recent results on malware identification.

Bio:
Terran Lane is an associate professor of computer science at UNM. His personal research interests include behavioral modeling and learning to act/behave (reinforcement learning), scalability, representation, and the tradeoff between stochastic and deterministic modeling. All of these represent different facets of his overall interest in scaling learning methods to large, complex spaces and using them to learn to perform lengthy, complicated tasks and to generalize over behaviors. While he attempts to understand the core learning issues involved, he often situates his work in domain studies in practical problems. Doing so both elucidates important issues and problems for the learning community and provides useful techniques to other disciplines.

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