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Virtualized Cloud Platform Management Using A Combined Neural Network And Wavelet Transform Strategy, Chunyu Liu 2018 California State University – San Bernardino

Virtualized Cloud Platform Management Using A Combined Neural Network And Wavelet Transform Strategy, Chunyu Liu

Electronic Theses, Projects, and Dissertations

This study focuses on implementing a log analysis strategy that combines a neural network algorithm and wavelet transform. Wavelet transform allows us to extract the important hidden information and features of the original time series log data and offers a precise framework for the analysis of input information. While neural network algorithm constitutes a powerfulnonlinear function approximation which can provide detection and prediction functions. The combination of the two techniques is based on the idea of using wavelet transform to denoise the log data by decomposing it into a set of coefficients, then feed the denoised data into a neural …


Cryptosystems Using Subgroup Distortion, Indira Chatterji, Delaram Kahrobaei, Ni Yen Lu 2018 l'Universite de Nice

Cryptosystems Using Subgroup Distortion, Indira Chatterji, Delaram Kahrobaei, Ni Yen Lu

Publications and Research

In this paper we propose cryptosystems based on subgroup distortion in hyperbolic groups. We also include concrete examples of hyperbolic groups as possible platforms.


Relating Justification Logic Modality And Type Theory In Curry–Howard Fashion, Konstantinos Pouliasis 2018 The Graduate Center, City University of New York

Relating Justification Logic Modality And Type Theory In Curry–Howard Fashion, Konstantinos Pouliasis

Dissertations, Theses, and Capstone Projects

This dissertation is a work in the intersection of Justification Logic and Curry--Howard Isomorphism. Justification logic is an umbrella of modal logics of knowledge with explicit evidence. Justification logics have been used to tackle traditional problems in proof theory (in relation to Godel's provability) and philosophy (Gettier examples, Russel's barn paradox). The Curry--Howard Isomorphism or proofs-as-programs is an understanding of logic that places logical studies in conjunction with type theory and -- in current developments -- category theory. The point being that understanding a system as a logic, a typed calculus and, a language of a class of categories constitutes …


Gradient Estimation For Attractor Networks, Thomas Flynn 2018 The Graduate Center, City University of New York

Gradient Estimation For Attractor Networks, Thomas Flynn

Dissertations, Theses, and Capstone Projects

It has been hypothesized that neural network models with cyclic connectivity may be more powerful than their feed-forward counterparts. This thesis investigates this hypothesis in several ways. We study the gradient estimation and optimization procedures for several variants of these networks. We show how the convergence of the gradient estimation procedures are related to the properties of the networks. Then we consider how to tune the relative rates of gradient estimation and parameter adaptation to ensure successful optimization in these models. We also derive new gradient estimators for stochastic models. First, we port the forward sensitivity analysis method to the …


Sparse Passive-Aggressive Learning For Bounded Online Kernel Methods, Jing LU, Doyen SAHOO, Peilin ZHAO, Steven C. H. HOI 2018 Singapore Management University

Sparse Passive-Aggressive Learning For Bounded Online Kernel Methods, Jing Lu, Doyen Sahoo, Peilin Zhao, Steven C. H. Hoi

Research Collection School Of Computing and Information Systems

One critical deficiency of traditional online kernel learning methods is their unbounded and growing number of support vectors in the online learning process, making them inefficient and non-scalable for large-scale applications. Recent studies on scalable online kernel learning have attempted to overcome this shortcoming, e.g., by imposing a constant budget on the number of support vectors. Although they attempt to bound the number of support vectors at each online learning iteration, most of them fail to bound the number of support vectors for the final output hypothesis, which is often obtained by averaging the series of hypotheses over all the …


R3: Reinforced Ranker-Reader For Open-Domain Question Answering, Shuohang WANG, Mo YU, Xiaoxiao GUO, Zhiguo WANG, Tim KLINGER, Wei ZHANG, Shiyu CHANG, Gerald TESAURO, Bowen ZHOU, Jing JIANG 2018 Singapore Management University

R3: Reinforced Ranker-Reader For Open-Domain Question Answering, Shuohang Wang, Mo Yu, Xiaoxiao Guo, Zhiguo Wang, Tim Klinger, Wei Zhang, Shiyu Chang, Gerald Tesauro, Bowen Zhou, Jing Jiang

Research Collection School Of Computing and Information Systems

In recent years researchers have achieved considerable success applyingneural network methods to question answering (QA). These approaches haveachieved state of the art results in simplified closed-domain settings such asthe SQuAD (Rajpurkar et al., 2016) dataset, which provides a pre-selectedpassage, from which the answer to a given question may be extracted. Morerecently, researchers have begun to tackle open-domain QA, in which the modelis given a question and access to a large corpus (e.g., wikipedia) instead of apre-selected passage (Chen et al., 2017a). This setting is more complex as itrequires large-scale search for relevant passages by an information retrievalcomponent, combined with a …


Cross-Language Learning For Program Classification Using Bilateral Tree-Based Convolutional Neural Networks, Duy Quoc Nghi BUI, Lingxiao JIANG, Yijun YU 2018 Singapore Management University

Cross-Language Learning For Program Classification Using Bilateral Tree-Based Convolutional Neural Networks, Duy Quoc Nghi Bui, Lingxiao Jiang, Yijun Yu

Research Collection School Of Computing and Information Systems

Towards the vision of translating code that implements an algorithm from one programming language into another, this paper proposes an approach for automated program classification using bilateral tree-based convolutional neural networks (BiTBCNNs). It is layered on top of two tree-based convolutional neural networks (TBCNNs), each of which recognizes the algorithm of code written in an individual programming language. The combination layer of the networks recognizes the similarities and differences among code in different programming languages. The BiTBCNNs are trained using the source code in different languages but known to implement the same algorithms and/or functionalities. For a preliminary evaluation, we …


Randomized Routing On Fat-Trees, Ronald I. Greenberg, Charles E. Leiserson 2018 Loyola University Chicago

Randomized Routing On Fat-Trees, Ronald I. Greenberg, Charles E. Leiserson

Ronald Greenberg

Fat-trees are a class of routing networks for hardware-efficient parallel computation. This paper presents a randomized algorithm for routing messages on a fat-tree. The quality of the algorithm is measured in terms of the load factor of a set of messages to be routed, which is a lower bound on the time required to deliver the messages. We show that if a set of messages has load factor lambda on a fat-tree with n processors, the number of delivery cycles (routing attempts) that the algorithm requires is O(lambda + lg n lg lg n) with probability 1-O(1/n). The best previous …


Universal Wormhole Routing, Ronald I. Greenberg, Hyeong-Cheol Oh 2018 Loyola University Chicago

Universal Wormhole Routing, Ronald I. Greenberg, Hyeong-Cheol Oh

Ronald Greenberg

We examine the wormhole routing problem in terms of the "congestion" c and "dilation" d for a set of packet paths. We show, with mild restrictions, that there is a simple randomized algorithm for routing any set of P packets in O(cdη + cLηlog P) time, where L is the number of flits in a packet, and η = min {d,L]; only a constant number of flits are stored in each queue at any time. Using this result, we show that a fat-tree network of area Θ(A) can simulate wormhole routing on any network of comparable area with O(log 3 …


The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg 2018 Loyola University Chicago

The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg

Ronald Greenberg

This paper shows that a fat-pyramid of area Θ(A) requires only O(log A) slowdown to simulate any competing network of area A under very general conditions. The result holds regardless of the processor size (amount of attached memory) and number of processors in the competing networks as long as the limitation on total area is met. Furthermore, the result is valid regardless of the relationship between wire length and wire delay. We especially focus on elimination of the common simplifying assumption that unit time suffices to traverse a wire regardless of its length, since the assumption becomes more and more …


Randomized Routing On Fat-Trees, Ronald I. Greenberg 2018 Selected Works

Randomized Routing On Fat-Trees, Ronald I. Greenberg

Ronald Greenberg

Fat-trees are a class of routing networks for hardware-efficient parallel computation. This paper presents a randomized algorithm for routing messages on a fat-tree. The quality of the algorithm is measured in terms of the load factor of a set of messages to be routed, which is a lower bound on the time required to deliver the messages. We show that if a set of messages has load factor lambda on a fat-tree with n processors, the number of delivery cycles (routing attempts) that the algorithm requires is O(lambda+lgnlglgn) with probability 1-O(1/ …


Universal Wormhole Routing, Ronald I. Greenberg, Hyeong-Cheol Oh 2018 Selected Works

Universal Wormhole Routing, Ronald I. Greenberg, Hyeong-Cheol Oh

Ronald Greenberg

In this paper, we examine the wormhole routing problem in terms of the “congestion” c and “dilation” d for a set of packet paths. We show, with mild restrictions, that there is a simple randomized algorithm for routing any set of P packets in O(cdη+cLηlogP) time with high probability, where L is the number of flits in a packet, and η=min{d,L}; only a constant number of flits are stored in each queue at any time. Using this result, we show that a fat-tree network of area Θ(A) can simulate wormhole routing on any network of comparable area with O(log^3 A) …


Single-Layer Channel Routing And Placement With Single-Sided Nets, Ronald I. Greenberg, Jau-Der Shih 2018 Selected Works

Single-Layer Channel Routing And Placement With Single-Sided Nets, Ronald I. Greenberg, Jau-Der Shih

Ronald Greenberg

This paper considers the optimal offset, feasible offset, and optimal placement problems for a more general form of single-layer VLSI channel routing than has usually been considered in the past. Most prior works require that every net has exactly one terminal on each side of the channel. As long as only one side of the channel contains multiple terminals of the same net, we provide linear-time solutions to all three problems. Such results are implausible if the placement of terminals is entirely unrestricted; in fact, the size of the output for the feasible offset problem may be Ω(n^2). The linear-time …


On The Difficulty Of Manhattan Channel Routing, Ronald I. Greenberg, Joseph JaJa, Sridhar Krishnamurthy 2018 Loyola University Chicago

On The Difficulty Of Manhattan Channel Routing, Ronald I. Greenberg, Joseph Jaja, Sridhar Krishnamurthy

Ronald Greenberg

We show that channel routing in the Manhattan model remains difficult even when all nets are single-sided. Given a set of n single-sided nets, we consider the problem of determining the minimum number of tracks required to obtain a dogleg-free routing. In addition to showing that the decision version of the problem isNP-complete, we show that there are problems requiring at least d+Omega(sqrt(n)) tracks, where d is the density. This existential lower bound does not follow from any of the known lower bounds in the literature.


On The Area Of Hypercube Layouts, Ronald I. Greenberg, Lee Guan 2018 Selected Works

On The Area Of Hypercube Layouts, Ronald I. Greenberg, Lee Guan

Ronald Greenberg

This paper precisely analyzes the wire density and required area in standard styles for the hypercube. It shows that the most natural, regular layout of a hypercube of N^2 nodes in the plane, in a NxN grid arrangement, uses floor(2N/3)+1 horizontal wiring tracks for each row of nodes. (In the process, we see that the number of tracks per row can be reduced by 1 with a less regular design, as can also be seen from an independent argument of Bezrukov et al.) This paper also gives a simple formula for the wire density at any cut position and a …


Minimizing Channel Density With Movable Terminals, Ronald I. Greenberg, Jau-Der Shih 2018 Loyola University Chicago

Minimizing Channel Density With Movable Terminals, Ronald I. Greenberg, Jau-Der Shih

Ronald Greenberg

We give algorithms to minimize density for channels with terminals that are movable subject to certain constraints. The main cases considered are channels with linear order constraints, channels with linear order constraints and separation constraints, channels with movable modules containing fixed terminals, and channels with movable modules and terminals. In each case, previous results for running time and space are improved by a factor of L/lg n and L , respectively, where L is the channel length and n is the number of terminals.


Minimizing Channel Density With Movable Terminals, Ronald I. Greenberg, Jau-Der Shih 2018 Selected Works

Minimizing Channel Density With Movable Terminals, Ronald I. Greenberg, Jau-Der Shih

Ronald Greenberg

We give algorithms to minimize density for VLSI channel routing problems with terminals that are movable subject to certain constraints. The main cases considered are channels with linear order constraints, channels with linear order constraints and separation constraints, channels with movable modules containing fixed terminals, and channels with movable modules and terminals. In each case, we improve previous results for running time and space by a factor of L/\lgn and L, respectively, where L is the channel length, and n is the number of terminals.


Parallel Algorithms For Single-Layer Channel Routing, Ronald I. Greenberg, Shih-Chuan Hung, Jau-Der Shih 2018 Selected Works

Parallel Algorithms For Single-Layer Channel Routing, Ronald I. Greenberg, Shih-Chuan Hung, Jau-Der Shih

Ronald Greenberg

We provide efficient parallel algorithms for the minimum separation, offset range, and optimal offset problems for single-layer channel routing. We consider all the variations of these problems that have linear-time sequential solutions rather than limiting attention to the ``river-routing'' context, where single-sided connections are disallowed. For the minimum separation problem, we obtain O(lgN) time on a CREW PRAM or O(lgN/lglgN) time on a CRCW PRAM, both with optimal work (processor-time product) of O(N), where N is the number of terminals. For the offset range problem, we obtain the same time and processor bounds as long as only one side of …


Parallel Algorithms For Single-Layer Channel Routing, Ronald I. Greenberg, Shih-Chuan Hung, Jau-Der Shih 2018 Selected Works

Parallel Algorithms For Single-Layer Channel Routing, Ronald I. Greenberg, Shih-Chuan Hung, Jau-Der Shih

Ronald Greenberg

We provide efficient parallel algorithms for the minimum separation, offset range, and optimal offset problems for single-layer channel routing. We consider all the variations of these problems that are known to have linear- time sequential solutions rather than limiting attention to the "river-routing" context, where single-sided connections are disallowed. For the minimum separation problem, we obtain O(lgN) time on a CREW PRAM or O(lgN / lglgN) time on a (common) CRCW PRAM, both with optimal work (processor- time product) of O(N), where N is the number of terminals. For the offset range problem, we obtain the same time and processor …


Packet Routing In Networks With Long Wires, Ronald I. Greenberg, Hyeong-Cheol Oh 2018 Loyola University Chicago

Packet Routing In Networks With Long Wires, Ronald I. Greenberg, Hyeong-Cheol Oh

Ronald Greenberg

In this paper, we examine the packet routing problem for networks with wires of differing length. We consider this problem in a network independent context, in which routing time is expressed in terms of "congestion" and "dilation" measures for a set of packet paths. We give, for any constant ϵ > 0, a randomized on-line algorithm for routing any set of Npackets in O((C lgϵ(Nd) + D lg(Nd))/lg lg(Nd)) time, where C is the maximum congestion and D is the length of the longest path, both taking wire delays into …


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