Physical Sciences and Mathematics | Open Access Articles

Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Stars Above, Earth Below : a Guide to Astronomy in the National Parks by Tyler Nordgren. Springer/Praxis, 2010 444p, 9781441916488 $29.95.

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Construction And Improvement Of A Scheffler Reflector And Thermal Storage Device, Jason Rapp

Physics

We constructed and successfully tested a 2 m2 parabolic dish solar concentrator (Scheffler Concentrator) to focus sunlight onto a stationary target. Present efforts are to decrease the construction complexity and cost of the concentrator. In order to store solar heat, we also constructed and are testing a thermal storage device made of sand (for thermal mass), and pumice (for insulation). Preliminary tests indicate thermal retention times of many hours. Present efforts are to increase accessible power, and structural integrity.

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Accelerated Erosion Of Saltmarshes Infested By The Non-Native Burrowing Crustacean Sphaeroma Quoianum, Timothy Mathias Davidson, Catherine E. De Rivera

Environmental Science and Management Faculty Publications and Presentations

Lateral erosion of saltmarshes is affected by many abiotic and biotic factors. While abiotic factors are typically regarded as primary drivers of erosion, biotic influences such as burrowing or bioturbating taxa can also extensively modify the physical structure of this marine habitat. Many estuaries on the Pacific coast of North America have been invaded by populations of the burrowing non-native isopod Sphaeroma quoianum, which are thought to exacerbate the erosion of saltmarshes. We conducted a mensurative experiment to examine the relationship between populations of S. quoianum and lateral erosion rate of saltmarshes in Coos Bay, Oregon, USA. After 1 …

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Multiple Visions Of Teachers' Understandings Of Mathematics, Ann Kajander, Ralph Mason, Peter Taylor, Edward Doolittle, Tom Boland, Dan Jarvis, Wes Maciejewski

Faculty Research, Scholarly, and Creative Activity

In this dialog, the notion of mathematical understanding as might be needed by classroom teachers is critically examined by mathematics educators, mathematicians, and a classroom teacher, based on the outcomes of recent work with expert classroom teachers. Terminology, assumptions and examples are discussed and analysed from a number of points of view. Ultimately, the goal is to construct common ground from which appropriate mathematics courses for future teachers might be developed and taught. The need for common terminology and a unifying framework from which to work becomes apparent as multiple interpretations and visions are discussed.

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3d Oceanographic Data Compression Using 3d-Odetlap, You Li, Tsz-Yam Lau, Christopher S. Stuetzle, Peter Fox, W. Randolph Franklin

Computer Science Faculty Publications

This paper describes a 3D environmental data compression technique for oceanographic datasets. With proper point selection, our method approximates uncompressed marine data using an over-determined system of linear equations based on, but essentially different from, the Laplacian partial differential equation. Then this approximation is refined via an error metric. These two steps work alternatively until a predefined satisfying approximation is found. Using several different datasets and metrics, we demonstrate that our method has an excellent compression ratio. To further evaluate our method, we compare it with 3D-SPIHT. 3D-ODETLAP averages 20% better compression than 3D-SPIHT on our eight test datasets, from …

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Quantitative Analysis Of Simulated Erosion For Different Soils, Zhongxian Chen, Christopher S. Stuetzle, Barbara Cutler, Jared Gross, W. Randolph Franklin, Thomas F. Zimmie

Computer Science Faculty Publications

Levee overtopping can lead to failure and cause catastrophic damage, as was the case during Hurricane Katrina. We present a computer simulation of erosion to study the development of the rills and gullies that form along an earthen embankment during overtopping. We have coupled 3D Smoothed Particle Hydrodynamics with an erodibility model to produce our simulation. Through comparison between simulations and between simulation and analogous laboratory experiments, we provide quantitative and qualitative results, evaluating the accuracy of our simulation.

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Null Model Analysis Of Species Associations Using Abundance Data, Werner Ulrich, Nicholas J. Gotelli

College of Arts and Sciences Faculty Publications

The influence of negative species interactions has dominated much of the literature on community assembly rules. Patterns of negative covariation among species are typically documented through null model analyses of binary presence/absence matrices in which rows designate species, columns designate sites, and the matrix entries indicate the presence (1) or absence (0) of a particular species in a particular site. However, the outcome of species interactions ultimately depends on population-level processes. Therefore, patterns of species segregation and aggregation might be more clearly expressed in abundance matrices, in which the matrix entries indicate the abundance or density of a species in …

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Applied Technologies And Prospects Of Conformance Control Treatments In China, Yuzhang Liu, Baojun Bai, Yefei Wang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

China is the largest user of chemical-based conformance control treatments and a series of technologies have been successfully developed and deployed in recent years. This paper first shows the milestones of development and application of conformance control technologies in China. Then integrated conformance control technologies are reviewed followed by the lessons we have learned, and then a few major specific conformance control technologies are addressed, including tracer injection and channels explanation, potentiometric testing to identify areal sweep efficiency, Pressure Index (PI) decisionmaking technology to select well candidate, complementary decision-making technology to select well candidate and design application parameters, and major …

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Geographic Factors Of Residential Burglaries - A Case Study In Nashville, Tennessee, Jonathan A. Hall

Masters Theses & Specialist Projects

This study examines geographic patterns and geographic factors of residential burglary at the Nashville, TN area for a twenty year period at five year interval starting in 1988. The purpose of this study is to identify what geographic factors have impacted on residential burglary rates, and if there were changes in the geographic patterns of residential burglary over the study period. Several criminological theories guide this study, with the most prominent being Social Disorganization Theory and Routine Activities Theory. Both of these theories focus on the relationships of place and crime. A number of spatial analysis methods are hence adopted …

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Model Checking Hierarchical Probabilistic Systems, Jun Sun, Songzheng Song, Yang Liu

Research Collection School Of Computing and Information Systems

Probabilistic modeling is important for random distributed algorithms, bio-systems or decision processes. Probabilistic model checking is a systematic way of analyzing finite-state probabilistic models. Existing probabilistic model checkers have been designed for simple systems without hierarchy. In this paper, we extend the PAT toolkit to support probabilistic model checking of hierarchical complex systems. We propose to use PCSP#, a combination of Hoare’s CSP with data and probability, to model such systems. In addition to temporal logic, we allow complex safety properties to be specified by non-probabilistic PCSP# model. Validity of the properties (with probability) is established by refinement checking. Furthermore, …

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Impact Investigation Of Reactor Fuel Operating Parameters On Reactivity For Use In Burnup Credit Applications, Tanya N. Sloma

UNLV Theses, Dissertations, Professional Papers, and Capstones

When representing the behavior of commercial spent nuclear fuel (SNF), credit is sought for the reduced reactivity associated with the net depletion of fissile isotopes and the creation of neutron-absorbing isotopes, a process that begins when a commercial nuclear reactor is first operated at power. Burnup credit accounts for the reduced reactivity potential of a fuel assembly and varies with the fuel burnup, cooling time, and the initial enrichment of fissile material in the fuel. With regard to long-term SNF disposal and transportation, tremendous benefits, such as increased capacity, flexibility of design and system operations, and reduced overall costs, provide …

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Visual Salience And Reference Resolution In Situated Dialogues: A Corpus-Based Evaluation., Niels Schütte, John D. Kelleher, Brian Mac Namee

Conference papers

Dialogues between humans and robots are necessarily situated and so, often, a shared visual context is present. Exophoric references are very frequent in situated dialogues, and are particularly important in the presence of a shared visual context - for example when a human is verbally guiding a tele-operated mobile robot. We present an approach to automatically resolving exophoric referring expressions in a situated dialogue based on the visual salience of possible referents. We evaluate the effectiveness of this approach and a range of different salience metrics using data from the SCARE corpus which we have augmented with visual information. The …

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The Impact Of Social Media On Software Engineering Practices And Tools, Margaret-Anne Storey, Christoph Treude, Arie Van Deursen, Li-Te Cheng

Research Collection School Of Computing and Information Systems

Today's generation of software developers frequently make use of social media, either as an adjunct or integrated into a wide range of tools ranging from code editors and issue trackers, to IDEs and web-based portals. The role of social media usage in software engineering is not well understood, and yet the use of these mechanisms influences software development practices. In this position paper, we advocate for research that strives to understand the benefits, risks and limitations of using social media in software development at the team, project and community levels. Guided by the implications of current tools and social media …

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Pulsed Laser Deposition Of Graphite Counter Electrodes For Dye-Sensitized Solar Cells, Krishna P. Acharya, Himal Khatri, Sylvain Marsillac, Bruno Ullrich, Pavel Anzenbacher, Mikhail Zamkov

Electrical & Computer Engineering Faculty Publications

We report on pulsed laser deposition of graphite onto flexible plastic and conductive glass substrates for use as a counter electrode in dye-sensitized solar cells. The efficiency of as-prepared graphite electrodes was tested using CdS-sensitized solar cell architecture resulting in external quantum efficiency comparable to that of conventional platinum counter electrodes. This work highlights the possibility of using pulsed laser deposited graphite as a low-cost alternative to platinum, which could be fabricated both on flexible and rigid substrates.

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Tuning The Morphology Of Au/Cds Nanocomposites Through Temperature-Controlled Reduction Of Gold-Oleate Complexes, Elena Khon, Nishshanka N. Hewa-Kasakarage, Ian Nemitz, Krishna Acharya, Mikhail Zamkov

Physics and Astronomy Faculty Publications

A general synthetic strategy for controlling the shape of gold domains grown onto CdS semiconductor nanocrystals is presented. The colloidal growth of Au nanoparticles is based on the temperature-controlled reduction of Au-oleate complexes on the surface of CdS and allows for precise tuning of nanoparticle diameters from 2.5 to 16 nm simply by adjusting the temperature of the growth solution, whereas the shape of Au/CdS nanocomposites can be controllably switched between matchsticks and barbells via the reaction rate. Depending on the exact morphology of Au and CdS domains, fabricated nanocomposites can undergo evaporation-induced self-assembly on a substrate either through end-to-end …

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Photoinduced Charge Separation In Platinum Acetylide Oligomers, Chen Liao, James E. Yarnell, Ksenija D. Glusac, Kirk S. Schanze

Chemistry Faculty Publications

The series of three donor-spacer-acceptor complexes, DPAF-Ptn-NDI, has been synthesized and characterized using time-resolved absorption spectroscopy In these complexes, the donor is a (diphenylamino)-2,7-fluorenylene (DPAF) unit, the acceptor is a naphthalene diimide (NDI), and the spacers are a series of platinum acetylides of varying lengths, [-Pt(PBu(3))(2)C C-Ph-C C-](n) (where Bu = n-butyl Ph = 1,4-phenylene and n = 1 2, and 3) Electrochemistry indicates that the DPAF-Ptn-NDI system has a charge transfer state at ca 1 5 eV above the ground state that is based on one electron transfer from the DPAF donor to the NDI acceptor Transient absorption spectroscopy …

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Electronic Properties Of N(5)-Ethyl Flavinium Ion, Vincent Sichula, Pavel Kucheryavy, Renat Khatmullin, Ying Hu, Ekaterina Mirzakulova, Shubham Vyas, Samuel F. Manzer, Christopher M. Hadad, Ksenija D. Glusac

Chemistry Faculty Publications

We investigated the electronic properties of N(5)-ethyl flavinium perchlorate (Et-Fl(+)) and compared them to those of its parent compound, 3-methyllumiflavin (Fl). Absorption and fluorescence spectra of Fl and Et-Fl(+) exhibit similar spectral features, but the absorption energy of Et-Fl(+) is substantially lower than that of Fl. We calculated the absorption signatures of Fl and Et-Fl(+) using time-dependent density functional theory (TD-DFT) methods and found that the main absorption bands of Fl and Et-Fl(+) are (pi,pi*) transitions for the S(1) and S(3) excited states. Furthermore, calculations predict that the S(2) state has (n,pi*) character. Using cyclic voltammetry and a simplistic consideration …

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Autonomous Underwater Vehicles As Tools For Deep-Submergence Archaeology, Christopher N. Roman, Ian Roderick Mather

Graduate School of Oceanography Faculty Publications

Marine archaeology beyond the capabilities of scuba divers is a technologically enabled field. The tool suite includes ship-based systems such as towed side-scan sonars and remotely operated vehicles, and more recently free-swimming autonomous underwater vehicles (AUVs). Each of these platforms has various imaging and mapping capabilities appropriate for specific scales and tasks. Broadly speaking, AUVs are becoming effective tools for locating, identifying, and surveying archaeological sites. This paper discusses the role of AUVs in this suite of tools, outlines some specific design criteria necessary to maximize their utility in the field, and presents directions for future developments. Results are presented …

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Evolution Of A Bluetooth Test Application Product Line: A Case Study, Narayanasamy Ramasubbu, Rajesh Krishna Balan

Research Collection School Of Computing and Information Systems

In this paper, we study the decision making process involved in the five year lifecycle of a Bluetooth software product produced by a large, multi-national test and measurement firm. In this environment, customer change requests either have to be added as a standard feature in the product, or developed as a special customized version of the product. We first discuss the influential factors, such as evolving standards, market share, installed-base, and complexity, which collectively determined how the firm responded to product change requests. We then develop a predictive decision model to test the collective impact of these factors on determining …

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Semi-Autonomous Virtual Valet Parking, Arne Suppe, Luis Navarro-Serment, Aaron Steinfeld

Research Collection School Of Computing and Information Systems

Despite regulations specifying parking spots that support wheelchair vans, it is not uncommon for end users to encounter problems with clearance for van ramps. Even if a driver elects to park in the far reaches of a parking lot as a precautionary measure, there is no guarantee that the spot next to their van will be empty when they return. Likewise, the prevalence of older drivers who experience significant difficulty with ingress and egress from vehicles is nontrivial and the ability to fully open a car door is important. This work describes a method and user interaction for low cost, …

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Model Checking A Model Checker: A Code Contract Combined Approach, Jun Sun, Yang Liu, Bin Cheng

Research Collection School Of Computing and Information Systems

Model checkers, like any complex software, are subject to bugs. Unlike ordinary software, model checkers are often used to verify safety critical systems. Their correctness is thus vital. Verifying model checkers is extremely challenging because they are always complicated in logic and highly optimized. In this work, we propose a code contract combined approach for checking model checkers and apply it to a home-grown model checker PAT. In this approach, we firstly embed programming contracts (i.e., pre/post-conditions and invariants) into its source code, which can capture correctness of model checking algorithms, underlying data structures, consistency between different model checking parameters, …

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On Some Recent Applications Of The Coanda Effect To Acoustics, Caroline Lubert

Caroline P Lubert

No abstract provided.

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Early And Often: Bringing More Parallelism Into Undergraduate Computer Science, Elizabeth Shoop, Et Al

Elizabeth Shoop

No abstract provided.

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The Impact Of Quality Management Systems During A Pebble Bed Modular Reactor Project : A Case Study, Lwandiso Zamxaka

Lwandiso L Zamxaka

In the nuclear industry, Quality Management Systems are extremely important,especially if one wishes to improve public acceptance of radioactive solutions.There is normally minimum communication between the public and scientists,especially in nuclear science. People are not comfortable with nuclear technology,based on the past history of the Chernobyl catastrophe. Consequently, it is difficult to discuss important and sensitive issues like disposing of nuclear waste. Quality Management Systems can improve public confidence and communication. Integrated Management Systems in the project planning stage of the project can be a proactive step towards preventing unnecessary delays and costs. There is a perception that quality is …

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The Politics Before The Politics: Census 2010, Reapportionment, And Redistricting, Karen Saxe, T. Ratliff

Karen Saxe

No abstract provided.

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Designing For Incentives: Better Information Sharing For Better Software Engineering, Mark Klein, Gabriel A. Moreno, David C. Parkes, Kurt Wallnau

Gabriel A. Moreno

Software-reliant systems permeate all aspects of modern society. The resulting interconnectedness and associated complexity has resulted in a proliferation of diverse stakeholders with conflicting goals. Thus, contemporary software engineering is plagued by incentive conflicts, in settling on design features, allocating resources during the development of products, and allocating computational resources at runtime. In this position paper, we describe some of these problems and outline a research agenda in bridging to the economic theory of mechanism design, which seeks to align incentives in multi-agent systems with private information and conflicting goals. The ultimate goal is to advance a principled methodology for …

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Assessing The Vulnerability Of Replicated Network Services, G.D. Bissias, B.N. Levine, Ramesh Sitaraman

Ramesh Sitaraman

Client-server networks are pervasive, fundamental, and include such key networks as the Internet, power grids, and road networks. In a client-server network, clients obtain a service by connecting to one of a redundant set of servers. These networks are vulnerable to node and link failures, causing some clients to become disconnected from the servers. We develop algorithms that quantify and bound the inherent vulnerability of a client-server network using semidefinite programming (SDP) and branch-and-cut techniques. Further, we develop a divide-and-conquer algorithm that solves the problem for large graphs. We use these techniques to show that: for the Philippine Power Grid …

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Management Of Land Use Land Cover Through The Application Of Remote Sensing, Geographic Information Systems And Simulation, Praveen Jha

Praveen Jha Dr

Deforestation and degradation of forest areas, including those in the Protected Areas (PAs), are major concerns in India. There were 2 broad objectives of the study: the technological objective pertained to the development of state-of-art programs that could serve as Decision Support Systems while finalizing plans and policy interventions, while the other objective aimed at generating geo-spatial data in 2 PAs. A part of the Eastern Himalaya biodiversity hotspot, Manas Tiger Reserve (MTR), Assam, India having an area of 2837.12 sq km and an important part of Rajaji-Corbett Tiger Conservation Unit, Rajaji National Park (RNP), Uttarakhand, India, having an area …

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A New Approach To Community Flood Education, Neil Dufty

Neil Dufty

No abstract provided.

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Towards Software Health Management With Bayesian Networks, Johann Schumann, Ole J. Mengshoel, Ashok Srivastava, Adnan Darwiche

Ole J Mengshoel

More and more systems (e.g., aircraft, machinery, cars) rely heavily on software, which performs safety-critical operations. Assuring software safety though traditional V&V has become a tremendous, if not impossible task, given the growing size and complexity of the software. We propose that iSWHM (Integrated SoftWare Health Management) can increase safety and reliability of high-assurance software systems. iSWHM uses advanced techniques from the area of system health management in order to continuously monitor the behavior of the software during operation, quickly detect anomalies and perform automatic and reliable root-cause analysis, while not replacing traditional V&V. Information provided by the iSWHM system …

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Full-Text Articles in Physical Sciences and Mathematics

Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt

Publications

Construction And Improvement Of A Scheffler Reflector And Thermal Storage Device, Jason Rapp

Physics

Accelerated Erosion Of Saltmarshes Infested By The Non-Native Burrowing Crustacean Sphaeroma Quoianum, Timothy Mathias Davidson, Catherine E. De Rivera

Environmental Science and Management Faculty Publications and Presentations

Multiple Visions Of Teachers' Understandings Of Mathematics, Ann Kajander, Ralph Mason, Peter Taylor, Edward Doolittle, Tom Boland, Dan Jarvis, Wes Maciejewski

Faculty Research, Scholarly, and Creative Activity

3d Oceanographic Data Compression Using 3d-Odetlap, You Li, Tsz-Yam Lau, Christopher S. Stuetzle, Peter Fox, W. Randolph Franklin

Computer Science Faculty Publications

Quantitative Analysis Of Simulated Erosion For Different Soils, Zhongxian Chen, Christopher S. Stuetzle, Barbara Cutler, Jared Gross, W. Randolph Franklin, Thomas F. Zimmie

Computer Science Faculty Publications

Null Model Analysis Of Species Associations Using Abundance Data, Werner Ulrich, Nicholas J. Gotelli

College of Arts and Sciences Faculty Publications

Applied Technologies And Prospects Of Conformance Control Treatments In China, Yuzhang Liu, Baojun Bai, Yefei Wang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Geographic Factors Of Residential Burglaries - A Case Study In Nashville, Tennessee, Jonathan A. Hall

Masters Theses & Specialist Projects

Model Checking Hierarchical Probabilistic Systems, Jun Sun, Songzheng Song, Yang Liu

Research Collection School Of Computing and Information Systems

Impact Investigation Of Reactor Fuel Operating Parameters On Reactivity For Use In Burnup Credit Applications, Tanya N. Sloma

UNLV Theses, Dissertations, Professional Papers, and Capstones

Visual Salience And Reference Resolution In Situated Dialogues: A Corpus-Based Evaluation., Niels Schütte, John D. Kelleher, Brian Mac Namee

Conference papers

The Impact Of Social Media On Software Engineering Practices And Tools, Margaret-Anne Storey, Christoph Treude, Arie Van Deursen, Li-Te Cheng

Research Collection School Of Computing and Information Systems

Pulsed Laser Deposition Of Graphite Counter Electrodes For Dye-Sensitized Solar Cells, Krishna P. Acharya, Himal Khatri, Sylvain Marsillac, Bruno Ullrich, Pavel Anzenbacher, Mikhail Zamkov

Electrical & Computer Engineering Faculty Publications

Tuning The Morphology Of Au/Cds Nanocomposites Through Temperature-Controlled Reduction Of Gold-Oleate Complexes, Elena Khon, Nishshanka N. Hewa-Kasakarage, Ian Nemitz, Krishna Acharya, Mikhail Zamkov

Physics and Astronomy Faculty Publications

Photoinduced Charge Separation In Platinum Acetylide Oligomers, Chen Liao, James E. Yarnell, Ksenija D. Glusac, Kirk S. Schanze

Chemistry Faculty Publications

Electronic Properties Of N(5)-Ethyl Flavinium Ion, Vincent Sichula, Pavel Kucheryavy, Renat Khatmullin, Ying Hu, Ekaterina Mirzakulova, Shubham Vyas, Samuel F. Manzer, Christopher M. Hadad, Ksenija D. Glusac

Chemistry Faculty Publications

Autonomous Underwater Vehicles As Tools For Deep-Submergence Archaeology, Christopher N. Roman, Ian Roderick Mather

Graduate School of Oceanography Faculty Publications

Evolution Of A Bluetooth Test Application Product Line: A Case Study, Narayanasamy Ramasubbu, Rajesh Krishna Balan

Research Collection School Of Computing and Information Systems

Semi-Autonomous Virtual Valet Parking, Arne Suppe, Luis Navarro-Serment, Aaron Steinfeld

Research Collection School Of Computing and Information Systems

Model Checking A Model Checker: A Code Contract Combined Approach, Jun Sun, Yang Liu, Bin Cheng

Research Collection School Of Computing and Information Systems

On Some Recent Applications Of The Coanda Effect To Acoustics, Caroline Lubert

Caroline P Lubert

Early And Often: Bringing More Parallelism Into Undergraduate Computer Science, Elizabeth Shoop, Et Al

Elizabeth Shoop

The Impact Of Quality Management Systems During A Pebble Bed Modular Reactor Project : A Case Study, Lwandiso Zamxaka

Lwandiso L Zamxaka

The Politics Before The Politics: Census 2010, Reapportionment, And Redistricting, Karen Saxe, T. Ratliff

Karen Saxe

Designing For Incentives: Better Information Sharing For Better Software Engineering, Mark Klein, Gabriel A. Moreno, David C. Parkes, Kurt Wallnau

Gabriel A. Moreno

Assessing The Vulnerability Of Replicated Network Services, G.D. Bissias, B.N. Levine, Ramesh Sitaraman

Ramesh Sitaraman

Management Of Land Use Land Cover Through The Application Of Remote Sensing, Geographic Information Systems And Simulation, Praveen Jha

Praveen Jha Dr

A New Approach To Community Flood Education, Neil Dufty

Neil Dufty

Towards Software Health Management With Bayesian Networks, Johann Schumann, Ole J. Mengshoel, Ashok Srivastava, Adnan Darwiche

Ole J Mengshoel