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Fisher Yu will present his Pre-FPO on Monday, July 18, 2016 at 1pm in CS 402
by Nicki Gotsis 13 Jul '16

13 Jul '16

Fisher Yu will present his Pre-FPO on Monday, July 18, 2016 at 1pm in CS 402. The members of his committee are: Thomas Funkhouser (adviser), Vladlen Koltun (reader;Intel), Szymon Rusinkiewicz (reader), Adam Finkelstein (non-reader), Kai Li (non-reader). Everyone is invited to attend his talk. The talk title and abstract follow below: Title: Pixel-Level Prediction of Depth and Semantics in Images Outline: Pixel-Level prediction is a common task in computer vision. Human eyes can assign each pixel 3D properties, such as depth and normal, and semantic meaning, such as object category and boundary. The pixel-level information can help algorithm process online content with finer granularity and help autonomous agents navigate in complicated environment. I will present my research in 3D geometry to predict pixel depth in previously impossible cases and convolutional networks that can improve image segmentation results substantially. I will also talk about my efforts to create large scale image dataset which may create new possibilities in computer vision research. I will first talk about pixel-level depth prediction from a set of images with very small motion. The images are taken from videos recording hand motion when he/she tries to hold the camera still. The scenario is challenging due to very small baseline. We analyze the SfM problem from geometry perspective and find an algorithm that can recover camera motion for most of the cases. Further, a multi-view stereo method robust to depth noise is developed to predict the depth at each pixel. We also show that the recovered depth can be useful for some computational photography applications. To predict the semantics of each pixel, or to do semantic image segmentation, we turn to convolutional networks, which is more powerful than the alternatives. A lot of works have studied how to use the network designed for image classification as basis to solve the segmentation problem. I argue that in order to design a better model for image segmentation, we have to change the basis to make it more suitable for segmentation. Toward this goal, I introduce dilated convolution as an additional building block for semantic segmentation and study its properties. We use dilated convolution to build a deeper network that has much wider receptive field than the original image classification network. Our model has got competitive performance on different datasets. Finally, I will introduce my on-going project, LSUN, which aims to make it possible to explore weakly annotated data to help solve the image segmentation problem. In LSUN project, we have collected orders of magnitude more labeled and unlabeled images than any previous datasets. To reach the scale, we design an iterative method to combine the advantages of classification models and human labeling. We also introduce additional statistical tests along the process so that the final labeled set has controlled precision. Up to now, we are able to collect around 70 million labeled images with about 90% labeling accuracy. Additional experiments show that LSUN dataset is poised to give us more insight in understanding images.

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Sema Berkiten will present her FPO, "Capturing, Processing, and Synthesizing Surfaces with Details" on Thursday, 7/21/2016 at 2:00 pm in CS 402.
by Nicki Gotsis 13 Jul '16

13 Jul '16

Sema Berkiten will present her FPO, "Capturing, Processing, and Synthesizing Surfaces with Details" on Thursday, 7/21/2016 at 2:00 pm, CS 402. The members of her committee are: Szymon Rusinkiewicz (adviser), readers: Adam Finkelstein and Hao Li (University of Southern California); and nonreaders: Thomas Funkhouser and David Dobkin. A copy of her thesis is available in Room 310. Everyone is invited to attend her talk. The talk abstract follow below. Geometry acquisition and processing have become increasingly popular in computer graphics and vision, with demand for high-quality models driven by advances in 3D printing, realistic real-time renderings of 3D avatars in video games, digital libraries for historical objects etc. In this thesis, we focus on techniques to produce and process detailed geometry including acquisition of real world objects, processing and fusing the captured data, and synthesizing new surfaces from existing ones. First, we summarize a 2D acquisition technique called photometric stereo to capture high resolution surface details. As a validation step, we solve a misalignment problem for photometric datasets. After the dataset is validated, the surface normals can be computed using one of the photometric stereo algorithms. In order to decide which algorithm to use, we present a synthetic photometric benchmark to evaluate various algorithms for different scenarios. To produce a detailed surface in 3D, we propose an approach to combine a rough 3D geometry with detailed normal maps obtained from different views. We begin with unaligned 2D normal maps and a rough 3D geometry, and automatically align each normal map to the 3D geometry. Next, we map the normals onto the surface, correct and seamlessly blend them together. We then optimize the geometry to produce a high-quality 3D model. Next, we introduce a semi-automated system to convert photometric datasets into geometry-aware non-photorealistic illustrations of surface details that obey the common conventions of epigraphy (black-and-white archaeological drawings of inscriptions). This system is composed of rectification of the surface normals to correct camera perspective, segmentation of the inscriptions from the background, classification of the inscription based on carving technique, and stylization of the inscriptions in various styles. Finally, we present an algorithm for realistically transferring surface details (specifically, displacement maps) from existing high-quality 3D models to simple shapes that may be created with easy-to-learn modeling tools. Our key insight is to use metric learning to find a combination of geometric features that successfully predicts detail-map similarities on the source mesh, and use the learned feature combination to drive the detail transfer

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Muneeb Ali is presenting his pre FPO on Thursday, June 30, 2016 at 3pm in CS 402
by Nicki Gotsis 28 Jun '16

28 Jun '16

Muneeb Ali is presenting his Pre FPO on Thursday, June 30, 2016 at 3pm in CS 402. The members of his committee are Andrea LaPaugh (advisor), Mike Freedman (reader), Arvind Narayanan (reader), Jen Rexford (non-reader), and Brian Kernighan (non-reader). Title and abstract follow below: Title: "Bootstrapping Trust in Distributed Systems with Blockchains" Abstract: Blockchains like Bitcoin and Ethereum have seen significant adoption in the past few years. Beyond their cryptocurrency uses, blockchains are being used to build new, decentralized versions of DNS and public-key infrastructure (PKI) that have no central points of trust. Blockchains can provide the basis for a general-purpose "trust layer" for Internet applications, but certain aspects of contemporary blockchains present technical limitations. Blockchains are hard to modify after initial deployment, they cannot store much data, they have slow writes (order of minutes), and the time to bootstrap new nodes increases linearly every day. Further, little production data or experience is available to guide design tradeoffs. In this thesis, we present the design of a new blockchain-based naming and storage system called Blockstack. Blockstack solves several limitations of contemporary blockchains and its design is informed by our experience of operating a large deployment of a decentralized PKI service built on top of the Namecoin blockchain. Our production deployment led to the discovery of a critical security problem on the Namecoin network along with highlighting network reliability and throughput challenges, while registering and updating over 33,000 entries. We present the design of (a) a migration framework for migrating from one blockchain to another under a failure of the underlying blockchain — our migration from Namecoin to Bitcoin used this framework and is the first crosschain migration of a production system running on blockchains, (b) a logically separate layer, virtualchain, which introduces novel new functionality to production blockchains without requiring any consensus-breaking changes from the underlying blockchain, and (c) a decentralized storage mechanism that is resistant to sybil-attacks. Blockstack is used as a general-purpose "trust layer" by a variety of applications/services, including a production PKI system for 57,000 users that has no single point of trust/failure and a large decentralized marketplace. Blockstack is released as open source software (http://github.com/blockstack).

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Xin Jin will present his FPO "Dynamical Control of Software-Defined Networks" on Wednesday, 6/29/2016 at 2pm in CS 401.
by Nicki Gotsis 22 Jun '16

22 Jun '16

Xin Jin will present his FPO "Dynamical Control of Software-Defined Networks" on Wednesday, 6/29/2016 at 2pm in CS 401. The members of his committee are Jennifer Rexford (adviser), Readers: David Walker and Ratul Mahajan (Microsoft Research); Nonreaders: Jennifer Rexford, David Walker, Aarti Gupta, Ratul Mahajan (Microsoft Research), and Nick Feamster. A copy of his thesis is available in Room 310. Everyone is invited to attend his talk. The abstract follow below. Network management is critical to provide fast, reliable and secure network services. Software-defined networking (SDN) is a new network architecture to simplify network management by integrating network control to a centralized control platform. Network operators run various applications on the control platform to perform different management tasks, like routing, monitoring, load balancing and firewall. These applications have complex interactions with each other, making it difficult to deploy and reason about their behaviors. The frequent network events, such as traffic shifts, cyber attacks, and device failures, further exacerbates the problem. Each application needs to reconfigure the network, in order to react to the events. It is challenging to correctly and efficiently combine configuration changes from multiple applications, distribute these changes to a distributed collection of network devices, and coordinate changes across network devices in different layers. In this thesis, we present a new control architecture that can efficiently handle network events for multiple applications and across the network and optical layers. We identify and study the following three key components of the architecture. (i) CoVisor: A network hypervisor that can compose multiple applications and can effi- ciently merge configuration changes from these applications in the face of network events. To protect the network from malicious and buggy applications, CoVisor also provides topology virtualization and fine-grained access control to constrain what each application can see and do. (ii) Dionysus: A network update scheduler that can quickly and consistently distribute configuration changes to multiple switches. Dionysus uses a dependency graph to capture the dependencies between update operations, and dynamically schedules the operations based on runtime conditions. The approach both eliminates undesirable transient behaviors like loops, blackholes and congestion, and reduces the update time. (iii) Owan: A traffic management system that can jointly control the optical and network layers. Owan optimizes optical circuit setup, routing and rate allocation together, and dynamically adapts them to workload changes. The joint management significantly improves data transfers over the wide area network. We have built software controllers and hardware testbeds, and evaluated them with prototype experiments and large-scale simulations using network topologies and traffic traces from production networks.

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Talk: James H. Graham, Today- 10am
by Nicole E. Wagenblast 22 Jun '16

22 Jun '16

Room: 402 Date: Wednesday, June 22 Time: 10am Host: Andrew Appel Trusted Software for Cybersecurity in Industrial Control Systems James H. Graham University of Louisville, Dept. of Electrical and Computer Engr. and True Secure SCADA, LLC This talk will discuss the use of seL4 and trusted software components in industrial control systems. The goal is to protect critical infrastructure installations against devastating cyber-attacks on the control systems which monitor, regulate and control these facilities (think for a moment about being without electrical power and water for a really long time!) This talk will include an overview of three successful attacks against supervisory control and data acquisition (SCADA) systems and a discussion of some approaches to mitigating these threats and their potential consequences through the use of trusted software components. Dr. James Graham’s research on ICS cybersecurity has been funded for ten years by the Dept. of Justice and the Dept. of Homeland Security and other national and state agencies. He worked as a product and process engineer for General Motors, and served as an engineering professor at Rensselaer Polytechnic Institute and at the University of Louisville for 34 years prior to retirement in 2014. He is co-founder and CEO of True Secure SCADA, LLC. _______________________________________________ talks mailing list talks(a)lists.cs.princeton.edu To edit subscription settings or remove yourself, use this link: https://lists.cs.princeton.edu/mailman/listinfo/talks _______________________________________________ talks mailing list talks(a)lists.cs.princeton.edu To edit subscription settings or remove yourself, use this link: https://lists.cs.princeton.edu/mailman/listinfo/talks

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Talk: James H. Graham, Wednesday, June 22- 10am
by Nicole E. Wagenblast 21 Jun '16

21 Jun '16

Room: 402 Date: Wednesday, June 22 Time: 10am Host: Andrew Appel Trusted Software for Cybersecurity in Industrial Control Systems James H. Graham University of Louisville, Dept. of Electrical and Computer Engr. and True Secure SCADA, LLC This talk will discuss the use of seL4 and trusted software components in industrial control systems. The goal is to protect critical infrastructure installations against devastating cyber-attacks on the control systems which monitor, regulate and control these facilities (think for a moment about being without electrical power and water for a really long time!) This talk will include an overview of three successful attacks against supervisory control and data acquisition (SCADA) systems and a discussion of some approaches to mitigating these threats and their potential consequences through the use of trusted software components. Dr. James Graham’s research on ICS cybersecurity has been funded for ten years by the Dept. of Justice and the Dept. of Homeland Security and other national and state agencies. He worked as a product and process engineer for General Motors, and served as an engineering professor at Rensselaer Polytechnic Institute and at the University of Louisville for 34 years prior to retirement in 2014. He is co-founder and CEO of True Secure SCADA, LLC. _______________________________________________ talks mailing list talks(a)lists.cs.princeton.edu To edit subscription settings or remove yourself, use this link: https://lists.cs.princeton.edu/mailman/listinfo/talks

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Talk: James H. Graham, Wednesday, June 22- 10am
by Nicole E. Wagenblast 16 Jun '16

16 Jun '16

Room: TBD Date: Wednesday, June 22 Time: 10am Host: Andrew Appel Trusted Software for Cybersecurity in Industrial Control Systems James H. Graham University of Louisville, Dept. of Electrical and Computer Engr. and True Secure SCADA, LLC This talk will discuss the use of seL4 and trusted software components in industrial control systems. The goal is to protect critical infrastructure installations against devastating cyber-attacks on the control systems which monitor, regulate and control these facilities (think for a moment about being without electrical power and water for a really long time!) This talk will include an overview of three successful attacks against supervisory control and data acquisition (SCADA) systems and a discussion of some approaches to mitigating these threats and their potential consequences through the use of trusted software components. Dr. James Graham’s research on ICS cybersecurity has been funded for ten years by the Dept. of Justice and the Dept. of Homeland Security and other national and state agencies. He worked as a product and process engineer for General Motors, and served as an engineering professor at Rensselaer Polytechnic Institute and at the University of Louisville for 34 years prior to retirement in 2014. He is co-founder and CEO of True Secure SCADA, LLC.

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Ankit Garg will present his FPO on Wednesday, June 15, 2016 at 11am in CS 302
by Nicki Gotsis 08 Jun '16

08 Jun '16

Ankit Garg will present his FPO, "INFORMATION THEORETIC RELAXATIONS IN COMPLEXITY THEORY" on Wednesday, June 15, 2016 at 11am in CS 302. The members of his committee are Mark Braverman (adviser), Readers: Zeev Dvir and Ran Raz (Weizmann Institute of Science); Nonreaders: Avi Wigderson (Math) and Bernard Chazelle. A copy of his thesis is available in Room 310. Everyone is invited to attend his talk. The abstract follow below. Since Shannon’s “A Mathematical Theory of Communication” [Sha48], information theory has found applicability in a wide range of scientific disciplines. Over the past two decades, information theory has reemerged in theoretical computer science as a mathematical tool with applications to streaming algorithms, data structures, communication complexity etc. Properties of mutual information such as additivity and chain rule play an important role in these applications. In this thesis, we apply information theoretic tools to study various problems in complexity theory. These include the study of information complexity and communication complexity [BGPW13a, BGPW13c, BG14], hardness amplification of 2-prover games [BG15], applications of quantum information complexity to the study of quantum communication complexity of disjointness [BGK+15] and the use of strong data processing inequalities to analyze communication complexity of distributed statistical estimation [GMN14, BGM+16]. Along the way, we also develop several information theoretic tools such as correlated sampling theorems, subadditivity properties of information and quantum information cost etc. which could be of independent interest.

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1-2pm Tue June 7 talk on network optimization in CS 302
by Jennifer Rexford 07 Jun '16

07 Jun '16

Speaker: Sanjay Rao, Purdue University Title: Robust Guarantees for Networks with Flexible Routing Date/time: 1-2pm Tuesday June 7 Location: CS 302 Abstract: A key challenge confronting network designers is verifying that their networks can properly cope with a wide range of traffic conditions and failure scenarios. Since many design choices (e.g., topology design, middlebox placement) are made over longer time-scales and cannot be easily adapted, it is important to ensure that a given design choice can perform well across traffic demands and failures. In this paper, we develop an optimization-theoretic framework to provide guaranteed bounds on link utilization across traffic patterns and failure scenarios of interest, while considering flexible routing strategies optimized for the specific scenario. Considering flexible routing strategies is important since oblivious strategies can be unduly conservative, but poses theoretical challenges that we address. We apply our framework to multiple case studies including design of MPLS tunnels, and routing in the presence of middleboxes. Evaluations over real network topologies and traffic data show the promise of the approach.

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Klaus-Tycho Förster today at 11am
by Nicole E. Wagenblast 01 Jun '16

01 Jun '16

Moving Network Flows without Congestion: Different Models, Different Complexities Wednesday June 1, 2016, 11am Computer Science 302 While the optimal utilization of networks with (multi-commodity) flows is a well-studied research area, the consistent migration of flows is still a relatively young field: If the demands in a network change, how can we satisfy these new demands without losing packets or rate-limiting flows in the process? Central control, as offered by Software Defined Networking, cannot change the network behavior instantaneously. E.g., due to asynchrony, links can be over-utilized in the migration, leading to (temporary) congestion. In this talk, we are going to look at consistent flow migration for different models, ranging from single-destination flows with weak consistency requirements and arbitrary flow paths, to multi-commodity flows along fixed new paths with truly lossless migration. (Joint ongoing work with Sebastian Brandt, Laurent Vanbever, and Roger Wattenhofer) Klaus-Tycho Foerster is a PhD candidate in the Computer Engineering and Networks Laboratory at ETH Zurich, advised by Roger Wattenhofer. Prior to joining ETH as a research assistant, he earned his master degrees in mathematics and computer science, both at the Braunschweig University of Technology. Klaus' research focus lies in distributed computing, graph algorithms, and Software Defined Networking: Funded by Microsoft Research, he is studying the complexity of consistent updates in SDNs.

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