Computer Sciences Commons^™

Differential Evolution With Deoptim, David Ardia, Kris Boudt, Peter Carl, Katharine M. Mullen, Brian G. Peterson

The R Journal

The R package DEoptim implements the Differential Evolution algorithm. This algorithm is an evolutionary technique similar to classic genetic algorithms that is useful for the solution of global optimization problems. In this note we provide an introduction to the package and demonstrate its utility for financial applications by solving a non-convex portfolio optimization problem.

Probabilistic Weather Forecasting In R, Chris Fraley, Adrian Raftery, Tilmann Gneiting, Mclean Sloughter, Veronica Berrocol

The R Journal

This article describes two R packages for probabilistic weather forecasting, ensembleBMA, which offers ensemble post-processing via Bayesian model averaging (BMA), and Prob ForecastGOP, which implements the geostatistical output perturbation (GOP) method. BMA forecasting models use mixture distributions, in which each component corresponds to an ensemble member, and the form of the component distribution depends on the weather parameter (temperature, quantitative precipitation or wind speed). The model parameters are estimated from training data. The GOP technique uses geostatistical methods to produce probabilistic fore casts of entire weather fields for temperature or pressure, based on a single numerical forecast on …

Kb-Anonymity: A Model For Anonymized Behavior-Preserving Test And Debugging Data, Aditya Budi, David Lo, Lingxiao Jiang, Lucia Lucia

Research Collection School Of Computing and Information Systems

It is often very expensive and practically infeasible to generate test cases that can exercise all possible program states in a program. This is especially true for a medium or large industrial system. In practice, industrial clients of the system often have a set of input data collected either before the system is built or after the deployment of a previous version of the system. Such data are highly valuable as they represent the operations that matter in a client's daily business and may be used to extensively test the system. However, such data often carries sensitive information and cannot …

Continuous Visible Nearest Neighbor Query Processing In Spatial Databases, Yunjun Gao, Baihua Zheng, Gencai Chen, Qing Li, Xiaofa Guo

Research Collection School Of Computing and Information Systems

In this paper, we identify and solve a new type of spatial queries, called continuous visible nearest neighbor (CVNN) search. Given a data set P, an obstacle set O, and a query line segment q in a two-dimensional space, a CVNN query returns a set of $${\langle p, R\rangle}$$ tuples such that $${p \in P}$$ is the nearest neighbor to every point r along the interval $${R \subseteq q}$$ as well as pis visible to r. Note that p may be NULL, meaning that all points in P are invisible to all points in R due to the obstruction of …

Work In Progress: Vortex Detection And Visualization For Design Of Micro Air Vehicles And Turbomachinery, Rhonda J. Vickery, Thomas Wischgoll, Christopher Koehler, Matthew Pickett, Neal Eikenberry, Lance Harris, Richard E. Snyder, Darius Sanders, Haibo Dong, Randall Hand, Hugh Thornburg

Computer Science and Engineering Faculty Publications

No abstract provided.

Recognizing Whether Sensors Are On The Same Body, Cory Cornelius, David Kotz

Dartmouth Scholarship

As personal health sensors become ubiquitous, we also expect them to become interoperable. That is, instead of closed, end-to-end personal health sensing systems, we envision standardized sensors wirelessly communicating their data to a device many people already carry today, the cellphone. In an open personal health sensing system, users will be able to seamlessly pair off-the-shelf sensors with their cellphone and expect the system to ıt just work. However, this ubiquity of sensors creates the potential for users to accidentally wear sensors that are not necessarily paired with their own cellphone. A husband, for example, might mistakenly wear a heart-rate …

Android Application Controlled Surge Protector, Lok An

Electrical Engineering

A significant amount of consumer electronics cannot be switched off completely without being unplugged. Standby power, also known as phantom power, refers to the electric power consumed by electronic appliances when they are switched off. There are some devices that need constant power; items like alarm clocks and security systems need constant power to function correctly. Some devices, such as video game consoles and televisions, consume power without offering any features. Electricity lost from standby power has been increasing with the amount of consumer electronics increasing in households.

This project’s goal is to create a low power remote that can …

The Object Of Platform Studies: Relational Materialities And The Social Platform (The Case Of The Nintendo Wii), Steven E. Jones, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

Racing the Beam: The Atari Video Computer System,by Ian Bogost and Nick Montfort, inaugurated thePlatform Studies series at MIT Press in 2009.We’ve coauthored a new book in the series, Codename: Revolution: the Nintendo Wii Video Game Console. Platform studies is a quintessentially Digital Humanities approach, since it’s explicitly focused on the interrelationship of computing and cultural expression. According to the series preface, the goal of platform studies is “to consider the lowest level of computing systems and to understand how these systems relate to culture and creativity.”In practice, this involves paying close attentionto specific hardware and software interactions--to the vertical …

Onboard Video Stabilization For Unmanned Air Vehicles, Nicholas Stewart Cross

Master's Theses

Unmanned Air Vehicles (UAVs) enable the observation of hazardous areas without endangering a pilot. Observational capabilities are provided by on-board video cameras and images are relayed to remote operators for analysis. However, vibration and wind cause video camera mounts to move and can introduce unintended motion that makes video analysis more difficult. Video stabilization is a process that attempts to remove unwanted movement from a video input to provide a clearer picture. 

This thesis presents an onboard video stabilization solution that removes high-frequency jitter, displays output at 20 frames per second (FPS), and runs on a Blackfin embedded processor. Any …

Point-Based Color Bleeding With Volumes, Christopher J. Gibson

Master's Theses

The interaction of light in our world is immensely complex, but with mod-

ern computers and advanced rendering algorithms, we are beginning to reach

the point where photo-realistic renders are truly difficult to separate from real

photographs. Achieving realistic or believable global illumination in scenes with

participating media is exponentially more expensive compared to our traditional

polygonal methods. Light interacts with the particles of a volume, creating com-

plex radiance patterns.

In this thesis, we introduce an extension to the commonly used point-based

color bleeding (PCB) technique, implementing volume scatter contributions. With

the addition of this PCB algorithm extension, we …

Minimum Time Kinematic Trajectories For Self-Propelled Rigid Bodies In The Unobstructed Plane, Andrei A. Furtuna

Dartmouth College Ph.D Dissertations

The problem of moving rigid bodies efficiently is of particular interest in robotics because the simplest model of a mobile robot or of a manipulated object is often a rigid body. Path planning, controller design and robot design may all benefit from precise knowledge of optimal trajectories for a set of permitted controls. In this work, we present a general solution to the problem of finding minimum time trajectories for an arbitrary self-propelled, velocity-bounded rigid body in the obstacle-free plane. Such minimum-time trajectories depend on the vehicle’s capabilities and on and the start and goal configurations. For example, the fastest …

Embedding Parallel Computation In A Stochastic Mesh Network: A Morphogenetic Approach, Max Orhai

Anthós

Many basic techniques in computer science have been founded on the assumption that physical computing resources are scarce but orderly, and that the cost of effective direct communication between physically distant parts of a computer system is affordable. In ubiquitous computing systems such as sensor networks, or in the design of nano-scale systems, these familiar assumptions may not hold.

What if we suppose instead that computing capacity is plentiful, but that only local communication is possible, and the exact structure of the communication network is not known in advance? This is the domain of spatial programming.

How can we program …

Shooting Neural Networks Algorithm For Solving Boundary Value Problems In Odes, Kais I. Ibraheem, Bashir M. Khalaf

Applications and Applied Mathematics: An International Journal (AAM)

The objective of this paper is to use Neural Networks for solving boundary value problems (BVPs) in Ordinary Differential Equations (ODEs). The Neural networks use the principle of Back propagation. Five examples are considered to show effectiveness of using the shooting techniques and neural network for solving the BVPs in ODEs. The convergence properties of the technique, which depend on the convergence of the integration technique and accuracy of the interpolation technique are considered.

A Study Of Semi-Automated Tracing, Jeffrey Holden

Master's Theses

Requirements tracing is crucial for software engineering practices including change analysis, regression testing, and reverse engineering. The requirements tracing process produces a requirements traceability matrix(TM) which links high- and low-level document elements. Manually generating a TM is laborious, time consuming, and error-prone. Due to these challenges TMs are often neglected. Automated information retrieval(IR) techniques are used with some efficiency. However, in mission- or safety-critical systems a human analyst is required to vet the candidate TM. This introduces semi-automated requirements tracing, where IR methods present a candidate TM and a human analyst validates it, producing a final TM. In semi-automated tracing …

The Utility Of Transient Sensitivity For Wildlife Management And Conservation: Bison As A Case Study, Michael Buhnerkempe, Nathanial Burch, Sarah J. Hamilton, Kerry M. Byrne, Eddie Childers, Kirstin A. Holfelder, Lindsay Mcmanus, Matthew I. Pyne, Greg Schroeder, Paul F. Doherty

Mathematics, Statistics and Computer Science Faculty Research and Publications

Developing effective management strategies is essential to conservation biology. Population models and sensitivity analyses on model parameters have provided a means to quantitatively compare different management strategies, allowing managers to objectively assess the resulting impacts. Inference from traditional sensitivity analyses (i.e., eigenvalue sensitivity methods) is only valid for a population at its stable age distribution, while more recent methods have relaxed this assumption and instead focused on transient population dynamics. However, very few case studies, especially in long-lived vertebrates where transient dynamics are potentially most relevant, have applied these transient sensitivity methods and compared them to eigenvalue sensitivity methods. We …

Standalone Software As An Active Medical Device, Martin Mchugh, Fergal Mccaffery, Valentine Casey

Conference papers

With the release of the latest European Medical Device Directive (MDD) standalone software can now be classified as an active medical device. Consequently the methods used to ensure device safety and reliability needs to be reviewed. IEC 62304 is the current software development lifecycle framework followed by medical device software developers but important processes are beyond the scope of IEC 62304. These processes are covered by additional standards. However since the MDD became mandatory these additional standards are not comprehensive enough to ensure the reliability of an active medical device consisting of only software. By employing software process improvement techniques …

Real-Time Trip Information Service For A Large Taxi Fleet, Rajesh Krishna Balan, Nguyen Xuan Khoa, Lingxiao Jiang

Research Collection School Of Computing and Information Systems

In this paper, we describe the design, analysis, implementation, and operational deployment of a real-time trip information system that provides passengers with the expected fare and trip duration of the taxi ride they are planning to take. This system was built in cooperation with a taxi operator that operates more than 15,000 taxis in Singapore. We first describe the overall system design and then explain the efficient algorithms used to achieve our predictions based on up to 21 months of historical data consisting of approximately 250 million paid taxi trips. We then describe various optimisations (involving region sizes, amount of …

Symbolic Quantum Circuit Simplification In Sympy, Matthew Curry

Physics

In the field of quantum information science, one can design a series of quantum logic operations known as a circuit. Circuits are the basis for quantum computations in quantum computing. As circuits will most likely be designed from a logical standpoint, there could exist mathematical redundancies which will lead to a larger circuit than necessary. These redundancies are computationally expensive, and there is a need for them to be found and eliminated to simplify the circuit. We present our research on finding the rules for simplifying circuits and its implementation in SymPy.

Wolf Ant, Gilbert L. Peterson, Christopher M. Mayer, Kevin Cousin

Faculty Publications

Ant colony optimization (ACO) algorithms can generate quality solutions to combinatorial optimization problems. However, like many stochastic algorithms, the quality of solutions worsen as problem sizes grow. In an effort to increase performance, we added the variable step size off-policy hill-climbing algorithm called PDWoLF (Policy Dynamics Win or Learn Fast) to several ant colony algorithms: Ant System, Ant Colony System, Elitist-Ant System, Rank-based Ant System, and Max-Min Ant System. Easily integrated into each ACO algorithm, the PDWoLF component maintains a set of policies separate from the ant colony's pheromone. Similar to pheromone but with different update rules, the PDWoLF policies …

Link Type Based Pre-Cluster Pair Model For Coreference Resolution, Yang Song, Houfeng Wang, Jing Jiang

Research Collection School Of Computing and Information Systems

This paper presents our participation in the CoNLL-2011 shared task, Modeling Unrestricted Coreference in OntoNotes. Coreference resolution, as a difficult and challenging problem in NLP, has attracted a lot of attention in the research community for a long time. Its objective is to determine whether two mentions in a piece of text refer to the same entity. In our system, we implement mention detection and coreference resolution seperately. For mention detection, a simple classification based method combined with several effective features is developed. For coreference resolution, we propose a link type based pre-cluster pair model. In this model, pre-clustering of …

Optimizing Sensor Data Acquisition For Energy-Efficient Smartphone-Based Continuous Event Processing, Archan Misra, Lipyeow Lim

Research Collection School Of Computing and Information Systems

Many pervasive applications, such as activity recognition or remote wellness monitoring, utilize a personal mobile device (aka smartphone) to perform continuous processing of data streams acquired from locally-connected, wearable, sensors. To ensure the continuous operation of such applications on a battery-limited mobile device, it is essential to dramatically reduce the energy overhead associated with the process of sensor data acquisition and processing. To achieve this goal, this paper introduces a technique of "acquisition-cost" aware continuous query processing, as part of the Acquisition Cost-Aware Query Adaptation (ACQUA) framework. ACQUA replaces the current paradigm, where the data is typically streamed (pushed) from …

Topical Keyphrase Extraction From Twitter, Xin Zhao, Jing Jiang, Jing He, Yang Song, Palakorn Achananuparp, Ee Peng Lim, Xiaoming Li

Research Collection School Of Computing and Information Systems

Summarizing and analyzing Twitter content is an important and challenging task. In this paper, we propose to extract topical keyphrases as one way to summarize Twitter. We propose a context-sensitive topical PageRank method for keyword ranking and a probabilistic scoring function that considers both relevance and interestingness of keyphrases for keyphrase ranking. We evaluate our proposed methods on a large Twitter data set. Experiments show that these methods are very effective for topical keyphrase extraction.

Preserving Transparency And Accountability In Optimistic Fair Exchange Of Digital Signatures, Xinyi Huang, Yi Mu, Willy Susilo, Jianying Zhou, Robert H. Deng

Research Collection School Of Computing and Information Systems

Optimistic fair exchange (OFE) protocols are useful tools for two participants to fairly exchange items with the aid of a third party who is only involved if needed. A widely accepted requirement is that the third party's involvement in the exchange must be transparent, to protect privacy and avoid bad publicity. At the same time, a dishonest third party would compromise the fairness of the exchange and the third party thus must be responsible for its behaviors. This is achieved in OFE protocols with another property called accountability. It is unfortunate that the accountability has never been formally studied in …

A Solution With Security Concern For Rfid-Based Track And Trace Services In Epcglobal-Enabled Supply Chains, Wei He, Yingjiu Li, Kevin Chiew, Tieyan Li, Eng Wah Lee

Research Collection School Of Computing and Information Systems

A supply chain represents the flow of materials, information, and finance as they move through supply chain partners such as manufacturers, suppliers, distributors, retailers, and consumers. The track & trace services in supply chains can help improve supply chain visibility and efficiency, and prevent counterfeiting and stealing of products thus enhance security. Track & trace services in supply chains require identification of items, capture of events as items move through supply chains, and query of events of items. RFID (radio frequency identification) is a technology that allows to identify objects simultaneously in a fully automated manner via radio waves. This …

On Combining State Space Reductions With Global Fairness Assumptions, Shao Jie Zhang, Jun Sun, Jun Pang, Yang Liu, Jin Song Dong

Research Collection School Of Computing and Information Systems

Model checking has established itself as an effective system analysis method, as it is capable of proving/dis-proving properties automatically. Its application to practical systems is however limited by state space explosion. Among effective state reduction techniques are symmetry reduction and partial order reduction. Global fairness often plays a vital role in designing self-stabilizing population protocols. It is known that combining fairness and symmetry reduction is nontrivial. In this work, we first show that global fairness, unlike weak/strong fairness, can be combined with symmetry reduction. We extend the PAT model checker with the technique and demonstrate its usability by verifying recently …

Effects Of Appearance And Functions On Likability And Perceived Occupational Suitability Of Robots, Sau-Lai Lee, Ivy Yee-Man Lau, Ying-Yi Hong

Research Collection School of Social Sciences

This article reports three experiments that examined the association between (a) appearances and perceived capabilities of robots, (b) appearance and capabilities of robots and liking for the robots, and (c) perceived capabilities of robots and judgments concerning their suitability for different occupations. In Experiment 1, the authors found that participants perceived human- and animal-like robots to have relatively more warmth-related (e.g., emotion) capabilities than machinelike robots have. In Experiment 2, the authors found that liking for robots was not affected by their human likeness or their having warmth or competence capabilities. In Experiment 3, participants generally thought that robots should …

Online Fault Detection Of Induction Motors Using Frequency Domain Independent Components Analysis, Zhaoxia Wang, C. S. Chang

Research Collection School Of Computing and Information Systems

This paper proposes an online fault detection method for induction motors using frequency-domain independent component analysis. Frequency-domain results, which are obtained by applying Fast Fourier Transform (FFT) to measured stator current time-domain waveforms, are analyzed with the aim of extracting frequency signatures of healthy and faulty motors with broken rotor-bar or bearing problem. Independent components analysis (ICA) is applied for such an aim to the FFT results. The obtained independent components as well as the FFT results are then used to obtain the combined fault signatures. The proposed method overcomes problems occurring in many existing FFT-based methods. Results using laboratory-collected …

A Feature Based Frequency Domain Analysis Algorithm For Fault Detection Of Induction Motors, Zhaoxia Wang, C. S. Chang, Zhang Yifan

Research Collection School Of Computing and Information Systems

This paper studies the stator currents collected from several inverter-fed laboratory induction motors and proposes a new feature based frequency domain analysis method for performing the detection of induction motor faults, such as the broken rotor-bar or bearing fault. The mathematical formulation is presented to calculate the features, which are called FFT-ICA features in this paper. The obtained FFT-ICA features are normalized by using healthy motor as benchmarks to establish a feature database for fault detection. Compare with conventional frequency-domain analysis method, no prior knowledge of the motor parameters or other measurements are required for calculating features. Only one phase …

Intelligent Systems Development In A Non Engineering Curriculum, Emily A. Brand, William L. Honig, Matthew Wojtowicz

Computer Science: Faculty Publications and Other Works

Much of computer system development today is programming in the large - systems of millions of lines of code distributed across servers and the web. At the same time, microcontrollers have also become pervasive in everyday products, economical to manufacture, and represent a different level of learning about system development. Real world systems at this level require integrated development of custom hardware and software.

How can academic institutions give students a view of this other extreme - programming on small microcontrollers with specialized hardware? Full scale system development including custom hardware and software is expensive, beyond the range of any …

Query Weighting For Ranking Model Adaptation, Peng Cai, Wei Gao, Aoying Zhou, Kam-Fai Wong

Research Collection School Of Computing and Information Systems

We propose to directly measure the importance of queries in the source domain to the target domain where no rank labels of documents are available, which is referred to as query weighting. Query weighting is a key step in ranking model adaptation. As the learning object of ranking algorithms is divided by query instances, we argue that it’s more reasonable to conduct importance weighting at query level than document level. We present two query weighting schemes. The first compresses the query into a query feature vector, which aggregates all document instances in the same query, and then conducts query weighting …