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Computer Science Faculty Publications and Presentations

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Full-Text Articles in Computer Sciences

Ear-Phone: A Context-Aware Noise Mapping Using Smart Phones, Rajib Rana, Chun Tung Chou, Nirupama Bulusu, Salil Kanhere, Wen Hu Jan 2015

Ear-Phone: A Context-Aware Noise Mapping Using Smart Phones, Rajib Rana, Chun Tung Chou, Nirupama Bulusu, Salil Kanhere, Wen Hu

Computer Science Faculty Publications and Presentations

A noise map facilitates the monitoring of environmental noise pollution in urban areas. It can raise citizen awareness of noise pollution levels, and aid in the development of mitigation strategies to cope with the adverse effects. However, state-of-the-art techniques for rendering noise maps in urban areas are expensive and rarely updated (for months or even years), as they rely on population and traffic models rather than on real data. Smart phone based urban sensing can be leveraged to create an open and inexpensive platform for rendering up-to-date noise maps. In this paper, we present the design, implementation and performance evaluation …


S-Store: Streaming Meets Transaction Processing, John Meehan, Nesime Tatbul, Cansu Aslantas, Ugur Cetintemel, Jiang Du, Tim Kraska, Samuel Madden, David Maier, Andrew Pavlo, Michael Stonebraker, Kristin A. Tufte, Hao Wang Jan 2015

S-Store: Streaming Meets Transaction Processing, John Meehan, Nesime Tatbul, Cansu Aslantas, Ugur Cetintemel, Jiang Du, Tim Kraska, Samuel Madden, David Maier, Andrew Pavlo, Michael Stonebraker, Kristin A. Tufte, Hao Wang

Computer Science Faculty Publications and Presentations

Stream processing addresses the needs of real-time applications. Transaction processing addresses the coordination and safety of short atomic computations. Heretofore, these two modes of operation existed in separate, stove-piped systems. In this work, we attempt to fuse the two computational paradigms in a single system called S-Store. In this way, S-Store can simultaneously accommodate OLTP and streaming applications. We present a simple transaction model for streams that integrates seamlessly with a traditional OLTP system. We chose to build S-Store as an extension of H-Store, an open-source, in-memory, distributed OLTP database system. By implementing S-Store in this way, we can make …


Desiderata For A Big Data Language, David Maier Jan 2015

Desiderata For A Big Data Language, David Maier

Computer Science Faculty Publications and Presentations

Data management and analytics systems for big data have proliferated, including column stores, array databases, graphanalysis environments and linear-algebra packages. This burgeoning of systems has lead to a surfeit of language and APIs. It is time to consider a new framework that can span these systems and simplify the programming and maintenance of Big Data applications. There are two key goals for such a framework:

Portability: It should be relatively easy to move an application or tool developed on one platform to operate against another. As a corollary, back-end data and analytics services should be swappable in a particular …


Default Rules In Functional Logic Programs, Sergio Antoy, Michael Hanus Jan 2015

Default Rules In Functional Logic Programs, Sergio Antoy, Michael Hanus

Computer Science Faculty Publications and Presentations

In functional logic programs, rules are applicable independently of textual order, i.e., any rule can potentially be used to evaluate an expression. This is similar to logic languages and opposite to functional languages, e.g., Haskell enforces a strict sequential interpretation of rules. However, in some situations it is convenient to express alternatives by means of compact default rules. Although default rules are often used in functional programs, the non-deterministic nature of functional logic programs does not allow to directly transfer this concept from functional to functional logic languages in a meaningful way. In this paper we propose a new concept …


Usage Based Topology For Dcns, Qing Yi, Suresh Singh Jan 2015

Usage Based Topology For Dcns, Qing Yi, Suresh Singh

Computer Science Faculty Publications and Presentations

Many data center network topologies are designed to provide full bisection bandwidth for tens of thousands of servers in order to achieve high network throughput and server agility. However, the utilization rate of DCNs on average is below 10%, which results in a significant waste of network resources and energy. Many researchers propose consolidating network traffic flows to maximize the set of idle network equipment and switching them to low power mode to save energy. In this paper, we propose using skinnier network topologies to meet performance requirements of realistic loads thus saving not only energy but capital cost as …


Query From Examples: An Iterative, Data-Driven Approach To Query Construction, Hao Li, Chee-Yong Chan, David Maier Jan 2015

Query From Examples: An Iterative, Data-Driven Approach To Query Construction, Hao Li, Chee-Yong Chan, David Maier

Computer Science Faculty Publications and Presentations

In this paper, we propose a new approach, called Query from Examples (QFE), to help non-expert database users construct SQL queries. Our approach, which is designed for users who might be unfamiliar with SQL, only requires that the user is able to determine whether a given output table is the result of his or her intended query on a given input database. To kick-start the construction of a target query Q, the user first provides a pair of inputs: a sample database D and an output table R which is the result of Q on D. As there will be …


A Theory Of Name Resolution, Pierre Néron, Andrew Tolmach, Eelco Visser, Guido Wachsmuth Jan 2015

A Theory Of Name Resolution, Pierre Néron, Andrew Tolmach, Eelco Visser, Guido Wachsmuth

Computer Science Faculty Publications and Presentations

We describe a language-independent theory for name binding and resolution, suitable for programming languages with complex scoping rules including both lexical scoping and modules. We formulate name resolution as a two-stage problem. First a language-independent scope graph is constructed using language-specific rules from an abstract syntax tree. Then references in the scope graph are resolved to corresponding declarations using a language-independent resolution process. We introduce a resolution calculus as a concise, declarative, and language- independent specification of name resolution. We develop a resolution algorithm that is sound and complete with respect to the calculus. Based on the resolution calculus we …


Clustering And Classification Of Email Contents, Izzat Alsmadi, Ikdam Alhami Jan 2015

Clustering And Classification Of Email Contents, Izzat Alsmadi, Ikdam Alhami

Computer Science Faculty Publications and Presentations

Information users depend heavily on emails’ system as one of the major sources of communication. Its importance and usage are continuously growing despite the evolution of mobile applications, social networks, etc. Emails are used on both the personal and professional levels. They can be considered as official documents in communication among users. Emails’ data mining and analysis can be conducted for several purposes such as: Spam detection and classification, subject classification, etc. In this paper, a large set of personal emails is used for the purpose of folder and subject classifications. Algorithms are developed to perform clustering and classification for …


Demonstrating "Data Near Here": Scientific Data Search, Veronika Margaret Megler, David Maier Jan 2015

Demonstrating "Data Near Here": Scientific Data Search, Veronika Margaret Megler, David Maier

Computer Science Faculty Publications and Presentations

Prior work proposed "Data Near Here" (DNH), a data search engine for scientific archives that is modeled on Internet search engines. DNH performs a periodic, asynchronous scan of each dataset in an archive, extracting lightweight features that are combined to form a dataset summary. During a search, DNH assesses the similarity of the search terms to the summary features and returns to the user, at interactive timescales, a ranked list of datasets for further exploration and analysis. We will demonstrate the search capabilities and ancillary metadata-browsing features for an archive of observational oceanographic data. While comparing search terms to complete …


Design Of A Flexible Component Gathering Algorithm For Converting Cell-Based Models To Graph Representations For Use In Evolutionary Search, Marianna Budnikova, Jeffrey W. Habig, Daniel Lobo, Nicolas Cornia, Michael Levin, Tim Andersen Jun 2014

Design Of A Flexible Component Gathering Algorithm For Converting Cell-Based Models To Graph Representations For Use In Evolutionary Search, Marianna Budnikova, Jeffrey W. Habig, Daniel Lobo, Nicolas Cornia, Michael Levin, Tim Andersen

Computer Science Faculty Publications and Presentations

Background

The ability of science to produce experimental data has outpaced the ability to effectively visualize and integrate the data into a conceptual framework that can further higher order understanding. Multidimensional and shape-based observational data of regenerative biology presents a particularly daunting challenge in this regard. Large amounts of data are available in regenerative biology, but little progress has been made in understanding how organisms such as planaria robustly achieve and maintain body form. An example of this kind of data can be found in a new repository (PlanformDB) that encodes descriptions of planaria experiments and morphological outcomes using a …


Learning Two-Input Linear And Nonlinear Analog Functions With A Simple Chemical System, Peter Banda, Christof Teuscher Apr 2014

Learning Two-Input Linear And Nonlinear Analog Functions With A Simple Chemical System, Peter Banda, Christof Teuscher

Computer Science Faculty Publications and Presentations

The current biochemical information processing systems behave in a predetermined manner because all features are defined during the design phase. To make such unconventional computing systems reusable and programmable for biomedical applications, adaptation, learning, and self-modification baaed on external stimuli would be highly desirable. However, so far, it haa been too challenging to implement these in real or simulated chemistries. In this paper we extend the chemical perceptron, a model previously proposed by the authors, to function as an analog instead of a binary system. The new analog asymmetric signal perceptron learns through feedback and supports MichaelisMenten kinetics. The results …


The Insecurity Of Two Proxy Signcryption Schemes: Proxy Credential Forgery Attack And How To Prevent It, Jyh-Haw Yeh Mar 2014

The Insecurity Of Two Proxy Signcryption Schemes: Proxy Credential Forgery Attack And How To Prevent It, Jyh-Haw Yeh

Computer Science Faculty Publications and Presentations

Securing different online e-business activities usually requires applying different cryptographic algorithms. The proxy signcryption algorithms are designed for applications such as online proxy auction or online proxy signatures on business contracts, which require a proxy agent to sign on confidential messages. This paper proposes a proxy credential forgery attack to two recent proxy signcryption schemes in the literature. Using the attack, a malicious proxy signer can create a fake proxy credential from his original credential to extend his signing power. Simple modifications to these two schemes are also provided in this paper to prevent the attack without adding too much …


Damage Spreading In Spatial And Small-World Random Boolean Networks, Qiming Lu, Christof Teuscher Feb 2014

Damage Spreading In Spatial And Small-World Random Boolean Networks, Qiming Lu, Christof Teuscher

Computer Science Faculty Publications and Presentations

The study of the response of complex dynamical social, biological, or technological networks to external perturbations has numerous applications. Random Boolean networks (RBNs) are commonly used as a simple generic model for certain dynamics of complex systems. Traditionally, RBNs are interconnected randomly and without considering any spatial extension and arrangement of the links and nodes. However, most real-world networks are spatially extended and arranged with regular, power-law, small-world, or other nonrandom connections. Here we explore the RBN network topology between extreme local connections, random small-world, and pure random networks, and study the damage spreading with small perturbations. We find that …


Visualization Of Off-Screen Data On Tablets Using Context-Providing Bar Graphs And Scatter Plots, Peter S. Games, Alark Joshi Feb 2014

Visualization Of Off-Screen Data On Tablets Using Context-Providing Bar Graphs And Scatter Plots, Peter S. Games, Alark Joshi

Computer Science Faculty Publications and Presentations

Visualizing data on tablets is challenging due to the relatively small screen size and limited user interaction capabilities. Standard data visualization apps provide support for pinch-and-zoom and scrolling operations, but do not provide context for data that is off-screen. When exploring data on tablets, the user must be able to focus on a region of interest and quickly find interesting patterns in the data. We present visualization techniques that facilitate seamless interaction with the region of interest on a tablet using context-providing bar graphs and scatter plots. Through aggregation, fisheye-style, and overview+detail representations, we provide context to the users as …


P2p Email Encryption By An Identity-Based One-Way Group Key Agreement Protocol, Jyh-Haw Yeh, Fiona Zeng, Thomas Long Jan 2014

P2p Email Encryption By An Identity-Based One-Way Group Key Agreement Protocol, Jyh-Haw Yeh, Fiona Zeng, Thomas Long

Computer Science Faculty Publications and Presentations

As a result of high-tech companies such as Google, Yahoo, and Microsoft offering free email services, email has become a primary channel of communication. However, email service providers have traditionally offered little in the way of message privacy protection. This has made emails, of which billions are sent around the world on any day, an attractive data source for personal identity information thieves. Google was one of the first companies to provide substantial email privacy protection when they began using the HTTPS always-on option to encrypt messages sent through their email service, Gmail. Unfortunately, Gmail's encryption option does not offer …


A Comparative Study Of Reservoir Computing For Temporal Signal Processing, Alireza Goudarzi, Peter Banda, Matthew R. Lakin, Christof Teuscher, Darko Stefanovic Jan 2014

A Comparative Study Of Reservoir Computing For Temporal Signal Processing, Alireza Goudarzi, Peter Banda, Matthew R. Lakin, Christof Teuscher, Darko Stefanovic

Computer Science Faculty Publications and Presentations

Reservoir computing (RC) is a novel approach to time series prediction using recurrent neural networks. In RC, an input signal perturbs the intrinsic dynamics of a medium called a reservoir. A readout layer is then trained to reconstruct a target output from the reservoir's state. The multitude of RC architectures and evaluation metrics poses a challenge to both practitioners and theorists who study the task-solving performance and computational power of RC. In addition, in contrast to traditional computation models, the reservoir is a dynamical system in which computation and memory are inseparable, and therefore hard to analyze. Here, we compare …


Guiding Data-Driven Transportation Decisions, Kristin A. Tufte, Basem Elazzabi, Nathan Hall, Morgan Harvey, Kath Knobe, David Maier, Veronika Margaret Megler Jan 2014

Guiding Data-Driven Transportation Decisions, Kristin A. Tufte, Basem Elazzabi, Nathan Hall, Morgan Harvey, Kath Knobe, David Maier, Veronika Margaret Megler

Computer Science Faculty Publications and Presentations

Urban transportation professionals are under increasing pressure to perform data-driven decision making and to provide data-driven performance metrics. This pressure comes from sources including the federal government and is driven, in part, by the increased volume and variety of transportation data available. This sudden increase of data is partially a result of improved technology for sensors and mobile devices as well as reduced device and storage costs. However, using this proliferation of data for decisions and performance metrics is proving to be difficult. In this paper, we describe a proposed structure for a system to support data-driven decision making. A …


Mqvc: Measuring Quranic Verses Similarity And Sura Classification Using N-Gram, Mohammed Akour, Izzat Alsmadi, Iyad Alazzam Jan 2014

Mqvc: Measuring Quranic Verses Similarity And Sura Classification Using N-Gram, Mohammed Akour, Izzat Alsmadi, Iyad Alazzam

Computer Science Faculty Publications and Presentations

Extensive research efforts in the area of Information Retrieval were concentrated on developing retrieval systems related to Arabic language for the different natural language and information retrieval methodologies. However, little effort was conducted in those areas for knowledge extraction from the Holly Muslim book, the Quran. In this paper, we present an approach (MQVC) for retrieving the most similar verses in comparison with a user input verse as a query. To demonstrate the accuracy of our approach, we performed a set of experiments and compared the results with an evaluation from a Quran Specialist who manually identified all relevant chapters …


Search Tool That Utilizes Scientific Metadata Matched Against User-Entered Parameters, Veronika Margaret Megler, David Maier Oct 2013

Search Tool That Utilizes Scientific Metadata Matched Against User-Entered Parameters, Veronika Margaret Megler, David Maier

Computer Science Faculty Publications and Presentations

A method for providing proximate dataset recommendations can begin with the creation of metadata records corresponding to datasets that represent scientific data by a scientific dataset search tool. The metadata records can conform to a standardized structural definition, and may be hierarchical. Values for the data elements of the metadata records can be contained within the datasets. Metadata records with a value that is proximate to a user-entered search parameter can be identified. A proximity score can be calculated for each identified metadata record. The proximity score can express a relevance of the corresponding dataset to the user-entered search parameters. …


The Grace Programming Language Draft Specification Version 0.3.53, Andrew P. Black, Kim B. Bruce, James Noble Aug 2013

The Grace Programming Language Draft Specification Version 0.3.53, Andrew P. Black, Kim B. Bruce, James Noble

Computer Science Faculty Publications and Presentations

This is a specification of the Grace Programming Language. This specification is notably incomplete and everything is subject to change. In particular, this version does not address the library, nested static type system, module system, metadata, immutable data and pure methods, and other areas. For discussion and rationale, see http://gracelang.org.

It is designed for use by university students learning programming in CS1 and CS2 classes that are based on object-oriented programming, faculty and teaching assistants developing materials for 1st and 2nd year programming classes, programming researchers needing an object-oriented programming language as a research vehicle, and programming designers in search …


Guinform: Interactive Fiction For Gui Prototyping, Tesca Fitzgerald Jun 2013

Guinform: Interactive Fiction For Gui Prototyping, Tesca Fitzgerald

Computer Science Faculty Publications and Presentations

There are many methods of rapidly prototyping a graphical user interface (GUI), the most prominent being paper prototyping and wireframe prototyping. In paper prototyping, the developer creates a physical GUI prototype using simple materials such as paper, pencils, and tabbed cards. Paper prototyping, while easy to implement, leads to unrealistic and awkward user interaction. Wireframe prototyping involves the use of simplified software tools to develop a primitive version of the proposed user interface. This method enables graceful interaction, but requires major implementation e↵ort. I propose a middle ground: a method of rapid, interactive GUI prototyping using Interactive Fiction (IF) tools. …


Based On Repeated Experience, System For Modification Of Expression And Negating Overload From Media And Optimizing Referential Efficiency, Peter R. Badovinatz, Veronika M. Megler Jun 2013

Based On Repeated Experience, System For Modification Of Expression And Negating Overload From Media And Optimizing Referential Efficiency, Peter R. Badovinatz, Veronika M. Megler

Computer Science Faculty Publications and Presentations

Content items are revealed to a user based on whether they have been previously reviewed by the user. A number of content items are thus received over time. The content items may be discrete content items, or may be portions of a content stream, and may be received over different media. For each content item, it is determined whether the content item was previously reviewed by a user. Where the content item was not previously reviewed, the item is revealed to the user, such as by being displayed or announced to the user. Where the content item was previously reviewed, …


Data Near Here: Bringing Relevant Data Closer To Scientists, Veronika M. Megler, David Maier May 2013

Data Near Here: Bringing Relevant Data Closer To Scientists, Veronika M. Megler, David Maier

Computer Science Faculty Publications and Presentations

Large scientific repositories run the risk of losing value as their holdings expand, if it means increased effort for a scientist to locate particular datasets of interest. We discuss the challenges that scientists face in locating relevant data, and present our work in applying Information Retrieval techniques to dataset search, as embodied in the Data Near Here application.


Object-Oriented Programming: Some History, And Challenges For The Next Fifty Years, Andrew P. Black Mar 2013

Object-Oriented Programming: Some History, And Challenges For The Next Fifty Years, Andrew P. Black

Computer Science Faculty Publications and Presentations

Object-oriented programming is inextricably linked to the pioneering work of Ole-Johan Dahl and Kristen Nygaard on the design of the Simula language, which started at the Norwegian Computing Centre in the Spring of 1961. However, object-orientation, as we think of it today—fifty years later—is the result of a complex interplay of ideas, constraints and people. Dahl and Nygaard would certainly recognize it as their progeny, but might also be amazed at how much it has grown up. This article is based on a lecture given on 22nd August 2011, on the occasion of the scientific opening of the Ole-Johan …


Interpreting Individual Classifications Of Hierarchical Networks, Will Landecker, Michael David Thomure, Luis M.A. Bettencourt, Melanie Mitchell, Garrett T. Kenyon, Steven P. Brumby Jan 2013

Interpreting Individual Classifications Of Hierarchical Networks, Will Landecker, Michael David Thomure, Luis M.A. Bettencourt, Melanie Mitchell, Garrett T. Kenyon, Steven P. Brumby

Computer Science Faculty Publications and Presentations

Hierarchical networks are known to achieve high classification accuracy on difficult machine-learning tasks. For many applications, a clear explanation of why the data was classified a certain way is just as important as the classification itself. However, the complexity of hierarchical networks makes them ill-suited for existing explanation methods. We propose a new method, contribution propagation, that gives per-instance explanations of a trained network's classifications. We give theoretical foundations for the proposed method, and evaluate its correctness empirically. Finally, we use the resulting explanations to reveal unexpected behavior of networks that achieve high accuracy on visual object-recognition tasks using well-known …


Modules And Dialects As Objects In Grace, Michael Homer, James Noble, Kim B. Bruce, Andrew P. Black Jan 2013

Modules And Dialects As Objects In Grace, Michael Homer, James Noble, Kim B. Bruce, Andrew P. Black

Computer Science Faculty Publications and Presentations

Grace is a gradually typed, object-oriented language for use in education; consonant with that use, we have tried to keep Grace as simple and straightforward as possible. Grace needs a module system for several reasons: to teach students about modular program design, to organise large programs, especially its self-hosted implementation, to provide access to resources defined in other languages, and to support different “dialects”—language subsets, or domain specific languages, for particular parts of the curriculum. Grace already has several organising constructs; this paper describes how Grace uses two of them, objects and lexical scope, to provide modules and dialects.


Taming The Metadata Mess, Veronika Margaret Megler Jan 2013

Taming The Metadata Mess, Veronika Margaret Megler

Computer Science Faculty Publications and Presentations

The rapid growth of scientific data shows no sign of abating. This growth has led to a new problem: with so much scientific data at hand, stored in thousands of datasets, how can scientists find the datasets most relevant to their research interests? We have addressed this problem by adapting Information Retrieval techniques, developed for searching text documents, into the world of (primarily numeric) scientific data. We propose an approach that uses a blend of automated and “semi-curated” methods to extract metadata from large archives of scientific data, then evaluates ranked searches over this metadata. We describe a challenge identified …


The Problem Of Semantics In The Metadata Mess, Veronika Margaret Megler, David Maier Jan 2013

The Problem Of Semantics In The Metadata Mess, Veronika Margaret Megler, David Maier

Computer Science Faculty Publications and Presentations

This presentation addresses problems related to the volume of available scientific data, and its accessibility or inaccessibility to researchers who seek it. Topics addressed include metadata and reducing semantic diversity, especially as they refer to geospatial and other architectures


Interactive Ambient Visualizations For Soft Advice, Emerson Murphy-Hill, Titus Barik, Andrew P. Black Jan 2013

Interactive Ambient Visualizations For Soft Advice, Emerson Murphy-Hill, Titus Barik, Andrew P. Black

Computer Science Faculty Publications and Presentations

Some software packages offer the user soft advice: recommendations that are intended to help the user create high quality artifacts, but which may turn out to be bad advice. It is left to the user to determine whether the soft advice really will improve quality, and to decide whether or not to adopt it. Visualizations can help the user in making this decision, but we believe that conventional visualizations are less than ideal. In this paper, we describe an interactive ambient visualization to help users identify, understand and interpret soft advice.

Our visualization was developed to help programmers interpret code …


On The Role Of Shape Prototypes In Hierarchical Models Of Vision, Michael David Thomure, Melanie Mitchell, Garrett T. Kenyon Jan 2013

On The Role Of Shape Prototypes In Hierarchical Models Of Vision, Michael David Thomure, Melanie Mitchell, Garrett T. Kenyon

Computer Science Faculty Publications and Presentations

We investigate the role of learned shape-prototypes in an influential family of hierarchical neural-network models of vision. Central to these networks’ design is a dictionary of learned shapes, which are meant to respond to discriminative visual patterns in the input. While higher-level features based on such learned prototypes have been cited as key for viewpointinvariant object-recognition in these models [1], [2], we show that high performance on invariant object-recognition tasks can be obtained by using a simple set of unlearned, “shape-free” features. This behavior is robust to the size of the network. These results call into question the roles of …