Browsing by Subject "Department of Computer Science and Engineering"

Now showing 1 - 10 of 10
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    Developing a Low-Cost UAV Avionics Package
    (2012-04-18) Taylor, Daniel
    The term 'unmanned Aerial Vehicle' (UAV) refers to flying vehicles not populated with humans. They are frequently used by a variety of groups, including the military, scientific researchers, and search-and-rescue workers to do things and go places that are impossible, dangerous, or just inconvenient for humans. The cost of these UAVs, however, is prohibitive in many cases. The UAV Research Group at the University of Minnesota is working on a low-cost UAV platform to alleviate this problem. The off-the-shelf components used to keep costs down, however, come with limited capabilities. Addressed here is the limited sensor and actuator connectivity available on the board used by the group. By creating an add-on board to read and write to sensors and actuators, we expanded the number of parts that can be added to the UAV, making this low-cost solution more feasible for practical applications.
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    Exploring Music Visualization Using MIDI and Java
    (2011-04-13) Fox, Nathan; Carlis, John
    Sheet music has been used to represent a musical piece. One problem with sheet music is its difficulty in displaying a wide range of pitches on a single staff. Also, to some, it is unclear what the relationship is between two notes at a glance. Most importantly, sheet music has difficulty illustrating volume changes, and it does not allow for a continuum of pitches. This research explored displaying notes on a spiral instead of a staff. The spiral uses spokes to represent common tones, and the notes in the music are represented as collections of cylinders along a time axis perpendicular to the spiral [Belifuss et al., 2003]. A three-dimensional musical display would be difficult to use effectively when read from a page. Computers, though, can represent such a structure usefully. Hence, we tried to develop a working piece of software based on the spiral display.
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    Finding the Way With Cyclopath
    (2011-04-13) Pitchford, David
    In the past few years, Cyclopath has become an outstanding example of a geographic wiki, or "geowiki", and a valuable resource to Twin Cities cyclists. For site creator Reid Priedhorsky, it has also been an opportunity to study recommender systems in a new context. In his doctoral thesis, he studied a variety of possible heuristics for predicting users' ratings of byways in the cities. However, his research only compared these predictors at the lowest, node level. This project extends the research to study how different predictors lead to the recommendation of different routes to users. This leads to higher level questions such as: How 'different' are two predictors? How 'different' are the routes that they generate? Does one generate 'better' routes than others? The ensemble predictors tested call into four main groups, which are similar within themselves but distinct from each other in the routes they generate. Though quantification of the differences in routes has been simple, evaluating the routes holistically--and the predictors that generated them--is beyond the scope of automated analysis and will have to be done by cyclists themselves.
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    How does eco-routing affect total system emissions? City network predictions from user equilibrium models
    (2022) Cotta Antúnez, Rocío; Levin, Michael W.
    Transportation contributes a substantial fraction of all greenhouse gas emissions. One approach for reducing such emissions is to modify vehicles' route choices to minimize their fuel consumption or emission, which is known as eco-routing. Most eco-routing is based on vehicles choosing routes that minimize their individual fuel consumption or emissions. The Braess paradox demonstrates that when vehicles choose routes to minimize their individual goals, the aggregate effect may paradoxically result in the opposite net effect due to changes in congestion patterns. We construct a multiclass user equilibrium model in which some vehicles use eco-routing and others seek to minimize their individual travel times. Using this model, we show that the Braess paradox exists for eco-routing. If a large number of vehicles are trying to minimize their fuel consumption or emissions, the total fuel consumption or emissions may increase. We then solve the multiclass user equilibrium on publicly available city network data, and find that eco-routing results in increases in fuel consumption and emissions on some city networks as well.
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    Modeling the Isoelectric Point of Mitochondria Using the Monte Carlo Method
    (2011-04-13) Noh, Ayoung
    Mitochondria are cellular organelles that produce energy in the form of adenosine triphosphate. Mitochondria may be affected by aging and also can be influenced by disease such as mitochondria disorders and cardiac dysfunction. A mitochondrion has inner and outer membranes that are compromised of phospholipid bilayers and proteins. The components of the outer membrane control how these organelles interact with other parts of the cell. The isoelectric point (pI) is the pH where a molecule or particle has no net charge. Mitochondria have a pI which depends on the phospholipids and proteins that make up the mitochondrial outer membrane. The goal of my project is to model the pI of the mitochondrial outer membrane consisting of phospholipids and amino acids to better understand experimental data. I have been writing a computer program that generates random compositions of amino acids and phospholipids on the surface of mitochondria by using the Monte Carlo method. This program automatically predicts the composition of the outer mitochondrial membrane based on experimental pI and produces a theoretical distribution that matches the experimental pI distribution. This result helps people understand the composition of the outer membrane of the mitochondria. I will use this program to build more detailed models of outer membranes of mitochondria.
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    Playing Cribbage with Reinforcement Learning and Minimax
    (2022) Partida, Ethan
    This project created a program to play the card game cribbage. Previous work on cribbage has focused on the discard phase of the game, using only a basic algorithm for the play phase. However, determining a hand’s potential performance in the play phase affects the optimal choice in the discard phase of the game. By ignoring this effect, current cribbage algorithms make un-optimal choices. We seek to alleviate this by creating an efficient and intelligent algorithm for the discard phase of cribbage. We explored two approaches to this algorithm, a reinforcement learning algorithm and a minimax algorithm. Due to the randomness of the play phase and our lack of computing power, we were not able to successfully train the reinforcement learning algorithm. By specifically tuning the minimax algorithm to suit the game of cribbage, we created an efficient algorithm which consistently out-preformed the naive greedy algorithm. We also introduce a variety of new heuristics to further tune the minimax algorithm for the play phase of cribbage.
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    Reading Between the Tweets: Clustering and Topic Extraction on Micro-Blogs
    (2010-04-21) Wolf, Katie
    According to Java et al., some of the main intentions of users on Twitter are daily chatting, conversations, sharing information/URLs, and reporting news. Topic extraction has been used in large documents such as online news articles, emails, scientific literature, and blogs, but little has been done with short documents like micro-blogs. Objective: Apply clustering and topic extraction techniques to micro-blogs as a first step toward tracking popular topics dynamically as they vary by time or location, or to enhance topic-related searches of tweets. The results found using a hybrid PDDP and K-Means clustering technique, typically used for categorizing large documents, have shown success when working with micro-blogs with noisy dictionaries. The methods show potential to be a basis for [semi-]supervised topic tracking and extraction using methods previously used for larger text documents.
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    Sleipnir: A Versatile Extremely Low Duty-Cycle Sensor Network
    (2009-10-07) Gu, Yu; He, Tian
    Wireless Sensor Network (WSN) is a new information paradigm based on the collaboration of a large number of self-organized sensing nodes that can be used for applications such as assisted living, infrastructure protection and scientific exploration. Along with advantages such as low-cost and low-profile, sensor networks are severely resource constrained, especially in terms of energy supply due to its small-form-factor. However, many sensor network based applications require a lifetime that can span tens of years. In order to bridge the gap between limited energy supply and long-term operation requirement, we then have to build extremely low duty-cycle sensor networks where sensor nodes stay in a dormant state for most of the time. In this thesis research, we initiate the first systematic research in this frontier under a wide spectrum of design space, including static, dynamic and mobile networks.
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    Using Data from the Cancer Genome Atlas to Investigate Molecular Events Related to Ovarian Cancer
    (2011-08-11) Liu, Xiaoye
    Ovarian Cancer is the most lethal gynecologic malignancy. Analyzing the molecular events related to ovarian cancer helps understand the pathogenesis of ovarian cancer from a genetic point of view. As miRNA singletons have been found significantly related to ovarian cancer and many other cancers, miRNAs have been recognized as an important riboregulator of gene expression. However, little is known about how pairs of miRNA expression profiles associate with ovarian cancer. In our analysis, we explored the combinatorial effects of miRNA pairs on regulating gene expression. We assessed the non-additive interaction between miRNA pairs on gene expression of patients that carry high grade ovarian cancer. We demonstrate how different miRNAs collectively contribute to ovarian cancer. We will illustrate two examples of miRNA pairs, hsa.miR.937 & hsa.let.7b and hsa.miR.1277& hsa.miR.485.3b, that we found exhibit non-additive interaction pattern on affecting gene expression of the patients with high grade Ovarian Cancer.
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    Using Virtual Reality Environments for Medical Devices Design
    (2009-10-07) Konchada, Vamsi; Coffey, Dane; Borazjani, Iman; Sotiropoulos, Fotis; Erdman, Arthur; Interrante, Victoria; Keefe, Daniel F.
    There is an urgent need for improved design methodologies and tools that give designers meaningful and accurate feedback early in the design process; virtual reality can be used to fill this need.  Virtual reality provides a highly engaging environment that allows user to experience and comprehend abstract concepts.  It can allow designers to broadly explore the space of potential design alternatives, and to expand the boundaries of complex designs that are possible given today's computer assisted tools.  Medical device researchers seek to better understand the complexities of cardiac anatomy, visualize how surrounding structures affect device function and deployment, and ultimately design more effective devices. Virtual representation combines visual graphics, virtual reality applications, finite element analysis based on the architecture of a 3D model. Introducing virtual reality based tools into the process of medical device design can significantly improve the process. We present our initial work aimed at developing new immersive visualization and interactive design tools for improving the medical device design process. Our initial work focuses on developing 3-dimensional visualizations of simulated blood flow through mechanical heart valves. Our goal is to develop 3D user interfaces for refining medical device designs within the context of patient-specific anatomy and simulated flow data.