Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Civil and Environmental Engineering (1522)
- Electrical and Computer Engineering (1516)
- Physical Sciences and Mathematics (1137)
- Mechanical Engineering (1130)
- Computer Engineering (1036)
-
- Civil Engineering (735)
- Materials Science and Engineering (616)
- Chemical Engineering (533)
- Environmental Engineering (523)
- Biomedical Engineering and Bioengineering (463)
- Computer Sciences (458)
- Aerospace Engineering (423)
- Operations Research, Systems Engineering and Industrial Engineering (362)
- Other Civil and Environmental Engineering (314)
- Data Storage Systems (303)
- Social and Behavioral Sciences (287)
- Hydraulic Engineering (285)
- Nanoscience and Nanotechnology (227)
- Electrical and Electronics (225)
- Life Sciences (220)
- Medicine and Health Sciences (208)
- Education (204)
- Environmental Sciences (184)
- Industrial Engineering (179)
- Physics (174)
- Power and Energy (155)
- Bioresource and Agricultural Engineering (153)
- Engineering Science and Materials (149)
- Structural Engineering (147)
- Institution
-
- Purdue University (626)
- Missouri University of Science and Technology (537)
- Brigham Young University (514)
- California Polytechnic State University, San Luis Obispo (362)
- University of Nebraska - Lincoln (337)
-
- University of Kentucky (201)
- Clemson University (186)
- Embry-Riddle Aeronautical University (174)
- University of Central Florida (174)
- Utah State University (171)
- University of Texas at Arlington (165)
- Engineering Conferences International (162)
- University of Arkansas, Fayetteville (149)
- Louisiana State University (133)
- Old Dominion University (129)
- Marquette University (125)
- University of South Carolina (125)
- Technological University Dublin (121)
- TÜBİTAK (121)
- Portland State University (108)
- University of South Florida (108)
- Michigan Technological University (103)
- Wright State University (103)
- University of Texas at El Paso (102)
- Santa Clara University (89)
- Georgia Southern University (86)
- Air Force Institute of Technology (83)
- Chinese Chemical Society | Xiamen University (78)
- University of Alabama at Birmingham (77)
- National Taiwan Ocean University (75)
- Keyword
-
- Applied sciences (173)
- Engineering (118)
- Conference (52)
- ASME (51)
- ECTC (51)
-
- Proceedings (51)
- Optimization (49)
- Simulation (40)
- Georgia Southern University (37)
- Modeling (34)
- Thermal Barrier Coatings (32)
- Sustainability (30)
- Design (28)
- Daniel Felix Ritchie School of Engineering and Computer Science (26)
- Energy (26)
- Mechanical Engineering (25)
- Nanoparticles (25)
- Santa Clara University (Calif.) (24)
- Student newspapers and periodicals (24)
- CFD (23)
- Concrete (22)
- Hydraulic fracturing (22)
- College of Engineering News (21)
- Fracing (20)
- Fracking (20)
- Microfluidics (20)
- Pure sciences (20)
- Transportation (20)
- UAV (20)
- Water (20)
- Publication
-
- Theses and Dissertations (326)
- International Congress on Environmental Modelling and Software (270)
- Electronic Theses and Dissertations (262)
- Open Access Theses (195)
- Faculty Publications (124)
-
- Masters Theses (124)
- Turkish Journal of Electrical Engineering and Computer Sciences (121)
- Electrical and Computer Engineering Faculty Research & Creative Works (118)
- The Summer Undergraduate Research Fellowship (SURF) Symposium (104)
- Open Access Dissertations (103)
- USF Tampa Graduate Theses and Dissertations (103)
- Master's Theses (97)
- Journal of Undergraduate Research (93)
- Graduate Theses and Dissertations (92)
- All Theses (88)
- LSU Master's Theses (82)
- Journal of Electrochemistry (78)
- Dissertations, Master's Theses and Master's Reports - Open (76)
- Open Access Theses & Dissertations (75)
- All Graduate Theses and Dissertations, Spring 1920 to Summer 2023 (71)
- Browse all Theses and Dissertations (71)
- Doctoral Dissertations (70)
- Journal of Marine Science and Technology–Taiwan (67)
- All Dissertations (66)
- Dissertations (61)
- CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018) (60)
- 5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry (59)
- Doctoral Dissertations and Master's Theses (57)
- Theses (56)
- International Conference on Durability of Concrete Structures (55)
- Publication Type
- File Type
Articles 2431 - 2460 of 7244
Full-Text Articles in Engineering
Development Of A Decision Support Tool To Allocate Irrigation Water On Competitive Basis: Application To Kathiraveli Village, Sri Lanka, Tom Le Cerf, Muhammed A. Bhuiyan
Development Of A Decision Support Tool To Allocate Irrigation Water On Competitive Basis: Application To Kathiraveli Village, Sri Lanka, Tom Le Cerf, Muhammed A. Bhuiyan
International Congress on Environmental Modelling and Software
This paper focuses specifically on the irrigation field and water supply tanks for ways to improve efficiency of water use and increase the resilience to climatic variability. The purpose of this paper is to develop an excel-based water balance model that will allow the maximum cropping area be planted in the upcoming agricultural season. The model consists of three modules: a crop water requirement calculator that allows the water requirements of specific crops to be compared, a water tank balance model, and a model which simulates the storage in the permanent wetland attached to the irrigation tank. The hydrological computation …
Modelling Biofilm Based Technologies With Activated Sludge Unit Processes: A Short Cut To Performance Simulation?, Noella Jones, Maebh Grace, Eoghan Clifford
Modelling Biofilm Based Technologies With Activated Sludge Unit Processes: A Short Cut To Performance Simulation?, Noella Jones, Maebh Grace, Eoghan Clifford
International Congress on Environmental Modelling and Software
Biofilm-based passive aeration systems (PAS) have attracted recent attention as alternative, energy efficient and low maintenance technologies in the wastewater sector. However the modelling of biofilm-based PAS offers unique challenges for modellers, particularly where new technologies are not easily simulated using existing commercial modelling software. However, if the modeller is concerned only with simulating "macro" plant performance (e.g. key effluent concentrations and cycle analysis) it may be possible to efficiently model these technologies using "surrogate" unit process systems (e.g. using an activated sludge process to model a biofilm process). The pumped flow biofilm reactor (PFBR); a batch biofilm technology, is …
A Best-Worst Scaling Model Of Climate Change Abatement By Australian Farmers, Marit E. Kragt, Nikki Dumbrell, Fiona Gibson
A Best-Worst Scaling Model Of Climate Change Abatement By Australian Farmers, Marit E. Kragt, Nikki Dumbrell, Fiona Gibson
International Congress on Environmental Modelling and Software
Storing carbon from the atmosphere in terrestrial sinks has been proposed as an important way to mitigate climate change and is a major focus in Australia's climate change policies. Mitigation by changing agricultural practices is seen as a promising way to achieve significant reductions in C02 concentrations. Several policies therefore aim to stimulate farmers to adopt so-called 'carbon farming' practices. However, there is little information about farmers' ability and willingness to adopt carbon farming. We present a best-worst scaling model to analyse farmers' decisions about adopting climate change mitigating practices. Best-worst scaling data was collected through a survey amongst mixed …
Hypothesis Testing For Management: Evolving And Answering Closed Questions Using Multiobjective Visualization, Joseph Kasprzyk, Joseph Guillaume, Joshua Kollat, Chris Danilo
Hypothesis Testing For Management: Evolving And Answering Closed Questions Using Multiobjective Visualization, Joseph Kasprzyk, Joseph Guillaume, Joshua Kollat, Chris Danilo
International Congress on Environmental Modelling and Software
In order to use models to understand deeply uncertain future conditions, managers must be able to pose and test hypotheses about their management problems. In Iterative Closed Question Methodology (ICQM), a series of closed questions are used to structure thinking about hypotheses while looking beyond a problem's existing modeling representation. Our research is exploring how ICQM can contribute to a framework called Many Objective Robust Decision Making (MORDM), which uses multiobjective optimization and ensembles of uncertain future states of the world to create and evaluate robust solutions for environmental management. A visualization software tool; AeroVis, has greatly aided implementation of …
The Virtual Learning Commons (Vlc): Enabling Sharing And Innovation For Flexible, Responsive Solutions, Deana D. Pennington, Alida Gándara, Nick Del Rio, Omar Ochoa
The Virtual Learning Commons (Vlc): Enabling Sharing And Innovation For Flexible, Responsive Solutions, Deana D. Pennington, Alida Gándara, Nick Del Rio, Omar Ochoa
International Congress on Environmental Modelling and Software
A key challenge in modeling of complex natural systems is identifying and integrating models and tools that are relevant, but were not developed for the targeted purpose. Modeling resources are proliferating, along with emerging technologies designed to enable discovery and integration of data and models. The goal of the Virtual Learning Commons (VLC) is to improve awareness and understanding of emerging methodologies and technologies, facilitate individual and group evaluation of these for innovative uses, and trace the impact of innovations across research communities. The VLC is funded by the U.S. National Science Foundation, and will be released in 2014. The …
Designing Innovative Linked Open Data And Semantic Technologies In Agro-Environmental Modelling, Rob Lokers, Stasinos Konstantopoulos, Armando Stellato, Rob Knapen, Sander Janssen
Designing Innovative Linked Open Data And Semantic Technologies In Agro-Environmental Modelling, Rob Lokers, Stasinos Konstantopoulos, Armando Stellato, Rob Knapen, Sander Janssen
International Congress on Environmental Modelling and Software
In recent years, innovative applications exploiting Linked Open Data (LOD) and the Semantic Web have opened up, combined and cross referenced high volumes of high-quality data and created tremendous new opportunities for data users as well as data providers. However, in order to serve the broadest community of users, technologies need to be developed that can manage large, constantly updated datasets and streams that are published in formats that were not designed with cross source linking in mind.
The EU-FP7 project SemaGrow aims to tackle this challenge by developing novel algorithms and methods for querying distributed triple stores, scalable and …
Testing Site-Specific Parameterizations Of Longwave Radiation Integrated In A Gis-Based Hydrological Model, Giuseppe Formetta, Olaf David, Riccardo Rigon
Testing Site-Specific Parameterizations Of Longwave Radiation Integrated In A Gis-Based Hydrological Model, Giuseppe Formetta, Olaf David, Riccardo Rigon
International Congress on Environmental Modelling and Software
Incoming (Rli) and outgoing (Rlo) longwave atmospheric radiation are very important components of the global radiation balance. They influence many hydrological processes such as evapotranspiration, soil-surface temperature, energy balance, and snowmelt. Field measures of Rli and Rlo are extremely rare except for a few sites and experimental watersheds. Many parameterization schemes were proposed in order to model Rli and Rlo by using easily available meteorological observations such as air temperature, relative humidity, incoming solar radiation and cloud cover.
In this work 10 methods of parameterizing clear sky radiation for the estimation of Rli and Rlo were integrated in the GIS …
An Application Of Geographical And Statistical Linked Data To Ecology: The Brazilian Cerrado Ontology Network And Qualitative Reasoning Models, Adriano Souza, Oscar Corcho, Paulo Salles, Luis Vilches-Blázquez
An Application Of Geographical And Statistical Linked Data To Ecology: The Brazilian Cerrado Ontology Network And Qualitative Reasoning Models, Adriano Souza, Oscar Corcho, Paulo Salles, Luis Vilches-Blázquez
International Congress on Environmental Modelling and Software
This work aims to link data about wood plant communities obtained from scientific studies about the Brazilian Cerrado biome, meteorological and environmental data, geographical information (maps) and Qualitative Reasoning (QR) conceptual models. An ontology network was developed in order to integrate data from different sources. Data Cube, AEMET, GeoSPARQL, and Time ontologies and QR formalism were used as general ontologies. In addition, two domain ontologies--Cerrado Concepts and Wood Plant Dynamics Ontology (Ccon) and Fire Ontology (Fire)--were developed to represent scientific knowledge about vegetation ecology focused on vegetation dynamics under different burning regimens. Datasets provided by Brazilian geovernment agencies and those …
Trade-Offs Of Biogas Production: Comparing Crop RoTations Under Different Climate Scenarios, Sven Lautenbach, Martin Volk, Micheal Strauch, Gerald Whittaker, Ralf Seppelt
Trade-Offs Of Biogas Production: Comparing Crop RoTations Under Different Climate Scenarios, Sven Lautenbach, Martin Volk, Micheal Strauch, Gerald Whittaker, Ralf Seppelt
International Congress on Environmental Modelling and Software
While increasing biofuel production is worldwide on the political agenda, concerns about the involved trade-offs are on the rise. However, the quantification of these trade-offs is typically based on the comparison of a limited number of plausible alternatives. We extended the analysis by applying a multi-objective genetic algorithm to estimate the set of Pareto optimal solutions which describe the trade-offs between the objectives. The Pareto solutions represent the (estimated) best options given the model and the specified control options. Our analysis studied food and fodder based crop rotations and two alternative biogas crop production schemes: a corn based production scheme …
Integrated Modelling Of Social-Ecological Systems: The Maelia High-Resolution Multi-Agent Platform To Deal With Water Scarcity Problems, Olivier Therond, Christophe Sibertin-Blanc, Romain Lardy, Benoit Gaudou, Maud Balestrat, Yi Hong, Thomas Louail, Van Bai Nguyen, David Panzoli, José-Miguel Sanchez-Perez, Sabine Sauvage, Patrick Taillandier, Maroussia Vavasseur, Pierre Mazzega
Integrated Modelling Of Social-Ecological Systems: The Maelia High-Resolution Multi-Agent Platform To Deal With Water Scarcity Problems, Olivier Therond, Christophe Sibertin-Blanc, Romain Lardy, Benoit Gaudou, Maud Balestrat, Yi Hong, Thomas Louail, Van Bai Nguyen, David Panzoli, José-Miguel Sanchez-Perez, Sabine Sauvage, Patrick Taillandier, Maroussia Vavasseur, Pierre Mazzega
International Congress on Environmental Modelling and Software
Sustainable water resource management is typical of environmental management problems emerging from complex social-ecological systems. It deeply depends upon water user strategies, land use management and water governance systems. MAELIA, a "policy issue" modelling platform, allows performing integrated assessment at watershed level of a wide range of scenarios regarding water and land use management strategies in combination with global changes. It has been developed through a strong analysis of different French water management situations and an inductive modelling process. It allows representing dynamic interactions between human activities (farming practices), ecological processes (hydrology and crop growth), and governance systems (water regulations …
Qualitative Reasoning Models To Summarize And Compare Metapopulation Theories, Isabella Gontijo Sá-Leão, Adriano Souza, Fernando Goulart, Paulo Salles
Qualitative Reasoning Models To Summarize And Compare Metapopulation Theories, Isabella Gontijo Sá-Leão, Adriano Souza, Fernando Goulart, Paulo Salles
International Congress on Environmental Modelling and Software
A better understanding of population dynamics is needed in the face of accelerating changes and modifications of natural landscapes. Qualitative Reasoning based models have been considered as a tool for integration and exploration of conceptual knowledge in ecological systems and population dynamics. The objective of the present work is to develop a set of qualitative models in order to capture, formalize, summarize, and compare knowledge about different approaches to metapopulation theory. Three types of approaches were modelled: 1) the classical concepts developed by Levins; 2) Pulliam's view on source and sink populations; and 3) an integrated model of conservation, based …
Linking Governance Storylines With The D-Expanse Model To Explore The Power System Transition Pathways, Evelina Trutnevyte
Linking Governance Storylines With The D-Expanse Model To Explore The Power System Transition Pathways, Evelina Trutnevyte
International Congress on Environmental Modelling and Software
In 2008 United Kingdom adopted an ambitious target to reduce its greenhouse gas emissions by 80% by 2050, compared to the levels of 1990. This is an unprecedented challenge to the power sector and multiple energy-environment-economic modeling activities have been undertaken to inform the energy policy to deliver this low-carbon transition. The role of governance, choices and strategies of the key actors is increasingly acknowledged as an influential determinant of such transition, but traditional energy-environment-economic models can hardly analyze these aspects. This paper proposes a methodological approach to integrating the governance aspects into energy-environment-economic modeling. In the Realizing Transition Pathways …
Assessment Of Policies For Low-Carbon Agriculture By Means Of Multi-Agent Simulation, Eygeny Latynskiy, Thomas Berger, Christian Troost
Assessment Of Policies For Low-Carbon Agriculture By Means Of Multi-Agent Simulation, Eygeny Latynskiy, Thomas Berger, Christian Troost
International Congress on Environmental Modelling and Software
Agriculture and agriculture-inflicted land use change is a major source of greenhouse gas (GHG) emissions. Reducing excessive deforestation and intensification of agricultural land use and consequently reducing associated GHG emissions is an important pathway of transition to a global low-carbon economy. Adoption of low-carbon agricultural systems and practices requires setting appropriate economic incentives for land users through smart policy instruments. For effective implementation of such instruments integrated ex-ante policy assessments are crucial. In this article we discuss and illustrate the benefits and potentials of applying multi-agent system models for the assessment of low-carbon policies and technologies. As an empirical example …
Empirical Agent-Based Modelling Of Everyday ProEnvironmental Behaviours At Work, Gary Polhill, Tony Craig, Amparo Alonso-Betanzos, Noelia Sanchez-Maroño, Óscar Fontenla-Romero, Adina Dumitru, Mirilia Bonnes, Marini Bonaiuto, Giuseppe Carrus, Ferdinando Fornara, Fridanna Maricchiolo, Linda Steg, Angela Ruepert, Kees Kaizer, Ricardo García-Mira
Empirical Agent-Based Modelling Of Everyday ProEnvironmental Behaviours At Work, Gary Polhill, Tony Craig, Amparo Alonso-Betanzos, Noelia Sanchez-Maroño, Óscar Fontenla-Romero, Adina Dumitru, Mirilia Bonnes, Marini Bonaiuto, Giuseppe Carrus, Ferdinando Fornara, Fridanna Maricchiolo, Linda Steg, Angela Ruepert, Kees Kaizer, Ricardo García-Mira
International Congress on Environmental Modelling and Software
We report on agent-based modelling work in the LOCAW project (Low Carbon at Work: Modelling Agents and Organisations to Achieve Transition to a Low Carbon Europe). The project explored the effectiveness of various backcasting scenarios conducted with case study organisations in bringing about pro-environmental change in the workforce in the domains of transport, energy use and waste. The model used qualitative representations of workspaces in formalising each scenario, and decision trees learned from questionnaire responses to represent decision-making. We describe the process by which the decision trees were constructed, noting that the use of decision trees in agent-based models requires …
Understanding Regime Shift In Land Systems With System Dynamics, Zhanli Sun, Daniel Müller
Understanding Regime Shift In Land Systems With System Dynamics, Zhanli Sun, Daniel Müller
International Congress on Environmental Modelling and Software
Land system change has major consequences for climate change, biodiversity and ecosystem services, and is central to the debate of sustainable development. Land policies aimed at guiding land system towards sustainable pathways need to be informed by better understanding of land system change, and often rely on the forecasting of future land system change. For example, initiatives of Reducing Emission from Deforestation and Forest Degradation (REDD+) provide financial incentives to developing countries in tropical regions in exchange for a reduction of carbon emission from land system compared to business-as-usual. REDD+ schemes therefore rely on predictions of future land use without …
Innovative Techniques For Quantitative Scenarios In Energy And Environmental Research: A Review, Evelina Trutnevyte, Célene Guivarch
Innovative Techniques For Quantitative Scenarios In Energy And Environmental Research: A Review, Evelina Trutnevyte, Célene Guivarch
International Congress on Environmental Modelling and Software
Quantitative scenarios form the core of the future analysis in the energy, climate and other environment-related fields. A growing number of researchers worldwide start using innovative techniques for developing, analysing and choosing quantitative scenarios. Some of these techniques involve a large number of scenarios. Different rationales motivate these strands of research: better system understanding, uncertainty analysis, development of robust strategies, selection of a small set of scenarios, ability to link storylines with quantitative scenarios and other. These techniques are argued to provide both novel research insights and policy-relevant scenario exercises. A workshop, organised by UCL Energy Institute and Cired, on …
Using Game Engine Technologies For Increasing Cognitive Stimulation And Perceptive Immersion, Garrett Keenaghan, Imre Horváth
Using Game Engine Technologies For Increasing Cognitive Stimulation And Perceptive Immersion, Garrett Keenaghan, Imre Horváth
Conference papers
With the development of more user friendly game engine packages and software, detailed cognitive stimulation of procedural activities has now become easier to develop in virtual reality environments. With packages offering built-in visual editors, the amount of labour hours required for the development of specific applications are reduced. This paper considers the use of computer supported game engine technology to provide location independent comprehension and procedural skills learning for built environment education.
Non-Linear Optimization Applied To Angle-Of-Arrival Satellite-Based Geolocation, Stephen D. Hartzell
Non-Linear Optimization Applied To Angle-Of-Arrival Satellite-Based Geolocation, Stephen D. Hartzell
Theses and Dissertations
Geolocation is a common application for satellite systems. This involves estimating an object's location (herein called the subject) based on noisy satellite data. Many geolocation methods exist; however, none are tailored specifically for the unique problems faced by satellite systems. Some satellites are so far from the subject being localized that by the time the satellite receives a signal from the subject it might have moved appreciably. Furthermore, some satellites or terrestrial sensors may be much closer to the subject than others. Therefore, sensors may need to be weighted based upon their distance to the subject being localized. In addition, …
Scalable System Design For Covert Mimo Communications, Jason R. Pennington
Scalable System Design For Covert Mimo Communications, Jason R. Pennington
Theses and Dissertations
In modern communication systems, bandwidth is a limited commodity. Bandwidth efficient systems are needed to meet the demands of the ever-increasing amount of data that users share. Of particular interest is the U.S. Military, where high-resolution pictures and video are used and shared. In these environments, covert communications are necessary while still providing high data rates. The promise of multi-antenna systems providing higher data rates has been shown on a small scale, but limitations in hardware prevent large systems from being implemented.
Proton Damage Effects On Carbon Nanotube Field-Effect Transistors, Evan R. Kemp
Proton Damage Effects On Carbon Nanotube Field-Effect Transistors, Evan R. Kemp
Theses and Dissertations
This research investigated the effects of proton damage on single-walled carbon nanotube (SWCNT) transistors. The transistors were irradiated by 1.8 MeV protons to determine the damage induced in the SWCNTs and the device substrate using Raman spectroscopy, and to observe the effect on transistor functionality by measuring current-voltage characteristics. Irradiation of the SWCNT transistors to a fluence of 1x1013 protons/cm2 resulted in 67% increase in the Raman D/G peak intensity ratio, while at a fluence of 2x1013 protons/cm2 the increase in the D/G ratio was only 18%, likely due to radiation annealing. Current-voltage measurements indicated an …
Air Force Inspection System: An Application For System-Of-Systems (Sos) Engineering, Joseph R. Lay
Air Force Inspection System: An Application For System-Of-Systems (Sos) Engineering, Joseph R. Lay
Theses and Dissertations
The Air Combat Command (ACC) Inspector General (IG) assesses the operational readiness and combat effectiveness of units by evaluating individual wings. Today's conflicts; however, are waged as a joint force. The Joint Forces Commander (JFC) leverages the resources of the entire military complex to achieve strategic objectives. The synergistic effects, created by the integration of individual weapon systems, produce greater results than the individual components. Evaluating wings outside the joint System of Systems (SoS) architecture does not provide a true assessment of combat readiness. Using a case study method, this research examines the idea of integrating a joint SoS architecture …
The Prospect Of Responsive Spacecraft Using Aeroassisted, Trans-Atmospheric Maneuvers, Robert A. Bettinger
The Prospect Of Responsive Spacecraft Using Aeroassisted, Trans-Atmospheric Maneuvers, Robert A. Bettinger
Theses and Dissertations
Comprised of exo- and trans-atmospheric trajectory segments, atmospheric re-entry represents a complex dynamical event which traditionally signals the mission end-of-life for low-Earth orbit spacecraft. Transcending this paradigm, atmospheric re-entry can be employed as a means of operational maneuver whereby aerodynamic forces can be exploited to create an aeroassisted maneuver. Utilizing a notional trans-atmospheric, lifting re-entry vehicle with L/D =6, the first phase of research demonstrates the terrestrial reachability potential for skip entry aeroassisted maneuvers. By overflying a geographically diverse set of ground targets, comparative analysis indicates a significant savings in delta V expenditure for skip entry compared with exo-atmospheric maneuvers. …
Minimization Of The Effects Of Secondary Reactions On Turbine Film Cooling In A Fuel Rich Environment, Andrew T. Shewhart
Minimization Of The Effects Of Secondary Reactions On Turbine Film Cooling In A Fuel Rich Environment, Andrew T. Shewhart
Theses and Dissertations
The demand for increased thrust, higher engine efficiency, and reduced fuel consumption has increased the turbine inlet temperature and pressure in modern gas turbine engines. The outcome of these higher temperatures and pressures is the potential for unconsumed radical species to enter the turbine. Because modern cooling schemes for turbine blades involve injecting cool, oxygen rich air adjacent to the surface, the potential for reaction with radicals in the mainstream flow and augmented heat transfer to the blade arises. This study evaluated various configurations of multiple cylindrical rows of cooling holes in terms of both heat release and effective downstream …
The Differential Vector Phase-Locked Loop For Global Navigation Satellite System Signal Tracking, James J. Brewer
The Differential Vector Phase-Locked Loop For Global Navigation Satellite System Signal Tracking, James J. Brewer
Theses and Dissertations
A novel differential vector phase-locked loop (DVPLL) is derived that takes GNSS code-phase and carrier-phase measurements from a base station and uses them to maintain an integer ambiguity resolved quality solution directly in the vector tracking loop of a rover receiver. The only state variables estimated and used to create the replica code and carrier signals from the base station measurements are three position and two clock states for a static test. Closing the individual loops solely through the navigation filter makes this a pure vector method. For short baselines, where differential atmospheric errors are small, the DVPLL can be …
A Study Of Slipper And Rail Wear Interaction At Low Speed, Greg V. Cavallaro
A Study Of Slipper And Rail Wear Interaction At Low Speed, Greg V. Cavallaro
Theses and Dissertations
The wear research presented in the work consists of results gathered from adapting a FEM based on a Holloman High Speed Test Track (HHSTT) mission executed in January 2008. The FEM consists of a VascoMax slipper sliding on a stationary AISI-1080 steel rail. The slipper is slid along the rail at speeds of 20 m/s and 40 m/s with complementary vertical velocities of -0.079 m/s and -0.059 m/s, respectively. The surface roughness caused by features such as asperities and valleys of the materials, is simulated in this model by five asperities, 1 micron to 5 microns on the rail and …
User Centered Design: Tools For Encouraging Climate Change Adaptation, Peter Verweij, Natascha Marinova, Rob Lokers
User Centered Design: Tools For Encouraging Climate Change Adaptation, Peter Verweij, Natascha Marinova, Rob Lokers
International Congress on Environmental Modelling and Software
Climate change and it’s societal response in the form of mitigation and adaptation strategies have potentially very large impacts in different sectors, especially on regions with a high vulnerability. Climate change will greatly affect agricultural and natural ecosystems and urban centers. The scale and complexity of the interactions represent a challenge for policy makers, researchers and the public at large. It is the role of the policy maker at different levels of government to facilitate and encourage adaptation and to achieve the level of transparency needed to obtain the public support for taking far-reaching measures. The European Climate Adaptation Platform …
Modelling The Impact Of Microbial Loop On Aquatic Food Webs, Yu Li, Liancong Luo, Vardit Makler-Pick, Emily K. Read, Matthew R. Hipsey
Modelling The Impact Of Microbial Loop On Aquatic Food Webs, Yu Li, Liancong Luo, Vardit Makler-Pick, Emily K. Read, Matthew R. Hipsey
International Congress on Environmental Modelling and Software
In order to control algal blooms, it is necessary to better understand microbial interactions in aquatic ecosystems. Based on the traditional "Nutrients-Phytoplankton-Zooplankton-Detritus" (NPZD) model, the "Nutrients-Phytoplankton-Zooplankton-Detritus+Bacteria" (NPZD+B) model has been developed to investigate the impact of the microbial loop on aquatic food webs via nutrient cycling processes. The results of the NPZD+B model showed the positive impact of the microbial loop on phytoplankton growth, and illustrated the importance of "bottom-up" (resource) control of algal blooms in aquatic ecosstems. The study concludes that the microbial loop is an important model component for simulating water quality dynamics when nutrients are limited in …
Parallel Simulation Of Environmental Phenomena, Ralf Denzer, Peter Fitch, Ioannis N. Athanasiadis, Daniel P. Ames
Parallel Simulation Of Environmental Phenomena, Ralf Denzer, Peter Fitch, Ioannis N. Athanasiadis, Daniel P. Ames
International Congress on Environmental Modelling and Software
This paper discusses the current situation with respect to the parallel simulation of environmental phenomena. It is not based on a complete and thorough investigation of the state-of- the-art in this domain and is more driven by observations, experiences and ideas of the four contributors who see the need to raise awareness towards a more systematic approach in the future. It is meant as a discussion paper to stimulate a more systematic approach towards parallel simulation in the environmental domain. While examples are mostly taken from hydrology, they are only used as illustration of a generic situation. The section on …
State And Trends In Mobile Observation Applications, Denis Havlik, Gerald Schimak
State And Trends In Mobile Observation Applications, Denis Havlik, Gerald Schimak
International Congress on Environmental Modelling and Software
The stellar growth of the smartphones and nearly gapless mobile network coverage in urban and suburban areas has widely extended the potential of the citizens' observatories. The possibility to easily record observations made by mobile citizens, and to automatically enrich this information using the built-in and external sensors sounds like a dream come true of the scientists and decision makers alike. However, in 2013 only a tiny portion of the potential users really participated in the citizen observation programs and the usability of the received information is often below expectations. The learning curve is often too high, sensor quality too …
Fronting Integrated Scientific Web Applications: Design Features And Benefits For Regulatory Environments, Jonathan Flaishans, Tao Hong, Marcia Snyder, Chancellor Pascale, Thomas S. Purucker
Fronting Integrated Scientific Web Applications: Design Features And Benefits For Regulatory Environments, Jonathan Flaishans, Tao Hong, Marcia Snyder, Chancellor Pascale, Thomas S. Purucker
International Congress on Environmental Modelling and Software
Integrated decision support systems for regulatory applications benefit from standard industry practices such as code reuse, test-driven development, and modularization. These approaches make meeting the federal government's goals of transparency, efficiency, and quality assurance more attainable, while facilitating science module updates and incorporation of new modules. The Obertool is a web-based dashboard suite of ecological risk assessment models supported by the United States Environmental Protection Agency that provides a cross-platform implementation for users. Its web-based approach provides users with a common interface to models developed in differing formats ranging from simple spreadsheet calculators to platform-dependent compiled executables. The dashboard combines …