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126816 full-text articles. Page 3434 of 3446.

Studies On The Development Of Novel Heterogeneous Catalysts For Transesterification Of Triglycerides In Biodiesel, João Gomes 2009 Instituto Superior Engenharia Lisboa

Studies On The Development Of Novel Heterogeneous Catalysts For Transesterification Of Triglycerides In Biodiesel, João Gomes

João F Gomes

No abstract provided.


Photocatalytic Thermodynamic Efficiency Factors. Practical Limits In Photocatalytic Reactors., Jesus Moreira del Rio, Benito Serrano Rosales, Aaron Ortiz Gomez, Hugo de Lasa 2009 The University of Western Ontario

Photocatalytic Thermodynamic Efficiency Factors. Practical Limits In Photocatalytic Reactors., Jesus Moreira Del Rio, Benito Serrano Rosales, Aaron Ortiz Gomez, Hugo De Lasa

Jesus Moreira del Rio

No abstract provided.


Performance Enhancement Of Absolute Polar Duty Cycle Division Multiplexing With Dual-Drive Mach–Zehnder-Modulator In 40gbit/S Optical Fiber Communication Systems, Ghafour Mahdiraji 2009 Selected Works

Performance Enhancement Of Absolute Polar Duty Cycle Division Multiplexing With Dual-Drive Mach–Zehnder-Modulator In 40gbit/S Optical Fiber Communication Systems, Ghafour Mahdiraji

Ghafour Amouzad Mahdiraji

We modeled and analyzed a method to improve receiver sensitivity of the Absolute Polar Duty Cycle Division Multiplexing (AP-DCDM) transmission system by using Dual-Drive Mach–Zehnder-Modulator (DD-MZM). It is found that by optimizing the bias voltage in DD-MZM, the sensitivity of the AP-DCDM can be improved. The optimizations lead towards the larger eye opening. As opposed to the previous work, in terms of receiver sensitivity and dispersion tolerance, similar performance for all channels was achieved. In comparison to the previously reported AP-DCDM system, this work resulted in almost 3.6 dB improvement of the receiver sensitivity, came together with acceptable ...


Learning Styles And Entrance Requirements For Online Master’S Programs, Stan Lightner, Mark Doggett, Vesta Whisler 2009 Western Kentucky University

Learning Styles And Entrance Requirements For Online Master’S Programs, Stan Lightner, Mark Doggett, Vesta Whisler

Mark Doggett

As more online graduate programs are created and traditional programs shift to an online format, the need to identify and understand skill sets necessary for students’ success becomes more apparent. Typically, graduate programs rely on entrance requirements such as the GRE, undergraduate GPA, and a writing sample to evaluate an applicant’s potential success. Is it reasonable to expect that other entrance requirements might be needed for student success in online graduate degree programs?

Research comparing learning and personality styles of online learners exists; however, application of this information as part of the admissions process for online graduate programs is ...


Minimizing Job Completion Time Variance For Service Stability On Identical Parallel Machines, Xueping Li, Yuerong Chen, Yang Sun 2009 University of Tennessee - Knoxville

Minimizing Job Completion Time Variance For Service Stability On Identical Parallel Machines, Xueping Li, Yuerong Chen, Yang Sun

Xueping Li

This paper addresses a job scheduling problem on multiple identical parallel machines so as to minimize job completion time variance (CTV). CTV minimization is closely related to the Just-In-Time philosophy and the service stability concept since it penalizes both earliness and tardiness. Its applications can be found in many real-life areas such as Internet data packet dispatching and production planning. This paper focuses on the unrestricted case of the problem where idle times are allowed to exist before machines start to process jobs. We prove several dominant properties about the optimal solution to the problem. For instance, we prove that ...


Toward Structured Public Involvement: Justice, Geography And Collaborative Geospatial/Geovisual Decision Support Systems, Keiron Bailey, Theodore Grossardt 2009 University of Arizona

Toward Structured Public Involvement: Justice, Geography And Collaborative Geospatial/Geovisual Decision Support Systems, Keiron Bailey, Theodore Grossardt

Dr. Theodore H. Grossardt

This article addresses how collaborative geospatial/geovisual decision support systems (C-GDSS) can achieve greater measures of spatial justice within an institutional, democratic framework for public goods allocation. Current public participation geographic information systems (PPGIS) and participatory geographic information science (P-GIS) literature identifies issues of scale and consensus as problematic for such systems. C-GDSS deployments aimed at achieving spatial justice through small-scale, consensual processes fail when scaled to large processes involving heterogeneous groups where consensus is not realistically achievable. For this case study, we identify a significant deficit in the quality of public involvement in transportation infrastructure (TI) planning and design ...


Modified Particle Swarm Optimization For Probabilistic Slope Stability Analysis, Mohammad Khajehzadeh, Ahmed El-shafie, Mohd Raihan Taha 2009 Civil and Structural Engineering, National University of Malaysia

Modified Particle Swarm Optimization For Probabilistic Slope Stability Analysis, Mohammad Khajehzadeh, Ahmed El-Shafie, Mohd Raihan Taha

Mohammad Khajehzadeh

No abstract provided.


Better To Be Frustrated Than Bored: The Incidence, Persistence, And Impact Of Learners' Cognitive-Affective States During Interactions With Three Different Computer-Based Learning Environments, Ryan Baker, Ma.Mercedes Rodrigo, Sidney D'Mello, Arthur Graesser 2009 Worcester Polytechnic Institute

Better To Be Frustrated Than Bored: The Incidence, Persistence, And Impact Of Learners' Cognitive-Affective States During Interactions With Three Different Computer-Based Learning Environments, Ryan Baker, Ma.Mercedes Rodrigo, Sidney D'Mello, Arthur Graesser

Ryan S.J.d. Baker

We study the incidence (rate of occurrence), persistence (rate of reoccurrence immediately after occurrence), and impact (effect on behavior) of students’ cognitive-affective states during their use of three different computer-based learning environments. Students’ cognitive-affective states are studied using different populations (Philippines, USA), different methods (quantitative field observation, self-report), and different types of learning environments (dialogue tutor, problemsolving game, and problem-solving based Intelligent Tutoring System). By varying the studies along these multiple factors, we can have greater confidence that findings which generalize across studies are robust. The incidence, persistence, and impact of boredom, frustration, confusion, engaged concentration, delight, and surprise were ...


Evaluation Of Photon Absorption In An Aqueous Tio2 Slurry Reactor Using Monte Carlo Simulations And Macroscopic Balance., Jesus Moreira del Rio, Benito Serrano Rosales, Aaron Ortiz Gomez, Hugo de Lasa 2009 The University of Western Ontario

Evaluation Of Photon Absorption In An Aqueous Tio2 Slurry Reactor Using Monte Carlo Simulations And Macroscopic Balance., Jesus Moreira Del Rio, Benito Serrano Rosales, Aaron Ortiz Gomez, Hugo De Lasa

Jesus Moreira del Rio

No abstract provided.


Evaluation Of Highway Design Parameters On Influencing Operator Speeds Through Casewise Visual Evaluation, Nikiforos Stamatiadis, Keiron Bailey, Theodore Grossardt, John Ripy 2009 University of Kentucky

Evaluation Of Highway Design Parameters On Influencing Operator Speeds Through Casewise Visual Evaluation, Nikiforos Stamatiadis, Keiron Bailey, Theodore Grossardt, John Ripy

Dr. Theodore H. Grossardt

Designing highways to influence driver operating speed effectively through environmental feedback is a key research field requiring special attention. Virtual reality video simulations were used to record the influence of environmental elements on driver judgments about the appropriate driving speed. This study evaluated the use of various means that could affect operating speeds and affect driver behavior without compromising safety. Data were analyzed through the fuzzy set nonlinear modeling system of Casewise Visual Evaluation methodology to identify design factors that most strongly influenced perceived operator discomfort. The findings indicated that vegetation type and density and barrier type have a significant ...


Aqueous-Phase Hydrogenation Of Acetic Acid Over Transition Metal Catalysts, George Huber, H. Olcay, L. Xu, Y Xu 2009 University of Massachusetts - Amherst

Aqueous-Phase Hydrogenation Of Acetic Acid Over Transition Metal Catalysts, George Huber, H. Olcay, L. Xu, Y Xu

George W. Huber

Catalytic hydrogenation of acetic acid to ethanol has been carried out in aqueous phase on several metals, with ruthenium being the most active and selective. DFT calculations suggest that the initial C[BOND]O bond scission yielding acetyl is the key step and that the intrinsic reactivity of the metals accounts for the observed activity.


High Order Sliding-Mode Dynamic Control For Chaotic Intracellular Calcium Oscillations, Ricardo Aguilar-López, Rafael Martinez-Guerra, Hector Puebla, Rogelio Hernandez 2009 Instituto Mexicano del Petroleo

High Order Sliding-Mode Dynamic Control For Chaotic Intracellular Calcium Oscillations, Ricardo Aguilar-López, Rafael Martinez-Guerra, Hector Puebla, Rogelio Hernandez

Ricardo Aguilar-López

In this article the closed-loop stability conditions and the control design of a class of biological system that exhibit chaotic oscillations are addressed. It is proved that the biological system is minimum phase. A class of nonlinear dynamic feedback control is designed using sliding-mode control ideas, which can be used for regulation, tracking and synchronization tasks. Numerical experiments illustrate the satisfactory performance of the proposed control methodology


Embedded Systems As Datacenters, Robert Iannucci 2009 RAI Laboratory LLC

Embedded Systems As Datacenters, Robert Iannucci

Robert A Iannucci

No abstract provided.


Milled Die Steel Surface Roughness Correlation With Steel Sheet Friction, J Berglund, Christopher Brown, B Rosén, N Bay 2009 Worcester Polytechnic Institute

Milled Die Steel Surface Roughness Correlation With Steel Sheet Friction, J Berglund, Christopher Brown, B Rosén, N Bay

Christopher A Brown

No abstract provided.


Downscaling Surface Temperature Images With Tsharp, Wonsook Ha, Prasanna Gowda, Terry Howell, George Paul, Jairo Hernandez, Sukantu Basu 2009 Boise State University

Downscaling Surface Temperature Images With Tsharp, Wonsook Ha, Prasanna Gowda, Terry Howell, George Paul, Jairo Hernandez, Sukantu Basu

Jairo E. Hernández

Daily evapotranspiration (ET) maps would significantly improve assessing crop water requirements, especially in the Texas High Plains (THP) where the supply of irrigation water is limited. Evapotranspireation maps derived from satellite data with daily coverage such as MODIS (Moderate Resolution Imaging Spectroradiometer) and GOES (Geostationary Operational Environmental Satellite) sensors are inadequate, because their thermal pixel size is larger than individual agricultural fields. However, there exists an opportunity to use simultaneously acquired high resolution visible, near-infrared, and shortwave-infrared images from MODIS, and thermal-infrared images from other high resolutions sensors such as LANDSAT 5 (Land Remote-Sensing Satellite) Thematic Mapper (TM) or ASTER ...


The Impact Of Lean Level Material Flow On Performance Of Manufacturing Systems For Large Complex Parts, Manocher Djassemi 2009 California Polytechnic State University, San Luis Obispo

The Impact Of Lean Level Material Flow On Performance Of Manufacturing Systems For Large Complex Parts, Manocher Djassemi

Eric Olsen

In this paper, the effectiveness of lean level load scheduling in manufacturing of large complex parts is discussed, and its impact on processing capacity is examined. These types of parts are common in aircraft manufacturing and shipbuilding, both of which can be characterized by large size and expensive capital equipment, low production volume, and long processing times. A discrete-event simulation model is constructed to assist decision making, with several part loading policies being modeled in detail. Data from a large aircraft manufacturer are used as input to the model. The results of simulation experiments indicate that lean level scheduling improves ...


Neuroimaging Study Designs, Computational Analyses And Data Provenance Using The Loni Pipeline, Ivo Dinov 2009 University of Michigan - Ann Arbor

Neuroimaging Study Designs, Computational Analyses And Data Provenance Using The Loni Pipeline, Ivo Dinov

Ivo D Dinov

Modern computational neuroscience employs diverse software tools and multidisciplinary expertise to analyze heterogeneous brain data. The classical problems of gathering meaningful data, fitting specific models, and discovering appropriate analysis and visualization tools give way to a new class of computational challenges—management of large and incongruous data, integration and interoperability of computational resources, and data provenance. We designed, implemented and validated a new paradigm for addressing these challenges in the neuroimaging field. Our solution is based on the LONI Pipeline environment [3], [4], a graphical workflow environment for constructing and executing complex data processing protocols. We developed study-design, database and ...


Assessing Misconceptions Of Undergraduate Engineering Students In The Thermal Sciences, Michael Prince, Margot Vigeant, K. Nottis 2009 Bucknell University

Assessing Misconceptions Of Undergraduate Engineering Students In The Thermal Sciences, Michael Prince, Margot Vigeant, K. Nottis

Margot A.S. Vigeant

No abstract provided.


The Impact Of Accurate Parameterization Of Snow Storage In Operational Hydrology Models, A. Burnop, Venkataramana Sridhar, J. McNamara, A. Flores 2009 Boise State University

The Impact Of Accurate Parameterization Of Snow Storage In Operational Hydrology Models, A. Burnop, Venkataramana Sridhar, J. Mcnamara, A. Flores

Venkataramana Sridhar

Ensuring that model inputs and parameters are correct and accurate is one of the largest challenges with hydrologic modeling, especially in regions with complex topography where snow is the predominant source of available water for the year. In these regions, meltwater does not necessarily enter a catchment where snow falls, but where it melts. Significant redistribution and differential melt can cause highly heterogeneous water inputs. Proper parameterization of end-of-season snow storage is essential. Aerial depletion curves relating changes in snow water equivalent to changes in snow covered area are commonly used to parameterize the impact of heterogeneous snow storage. However ...


Electromechanically Driven Chaotic Dynamics Of Voids In Metallic Thin Films, Dimitrios Maroudas, M. Gungor, V. Tomar 2009 University of Massachusetts - Amherst

Electromechanically Driven Chaotic Dynamics Of Voids In Metallic Thin Films, Dimitrios Maroudas, M. Gungor, V. Tomar

Dimitrios Maroudas

We report a systematic investigation of complex asymptotic states reached in the electromigration-driven morphological evolution of void surfaces in thin films of face-centered cubic metals with ⟨110⟩- and ⟨100⟩-oriented film planes under the simultaneous action of biaxial tension. The analysis is based on self-consistent dynamical simulations according to a realistic, well-validated, and fully nonlinear model. For ⟨110⟩-oriented film planes, we show that upon increasing the applied mechanical stress level, morphologically stable steady states transition to time-periodic states through a subcritical Hopf bifurcation. Further increase in the stress level triggers a sequence of period-doubling bifurcations that sets the driven ...


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