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Articles 391 - 420 of 656

Full-Text Articles in Physical Sciences and Mathematics

Design And Verification Environment For High-Performance Video-Based Embedded Systems, Michael Mefenza Nentedem May 2015

Design And Verification Environment For High-Performance Video-Based Embedded Systems, Michael Mefenza Nentedem

Graduate Theses and Dissertations

In this dissertation, a method and a tool to enable design and verification of computation demanding embedded vision-based systems is presented. Starting with an executable specification in OpenCV, we provide subsequent refinements and verification down to a system-on-chip prototype into an FPGA-Based smart camera. At each level of abstraction, properties of image processing applications are used along with structure composition to provide a generic architecture that can be automatically verified and mapped to the lower abstraction level. The result is a framework that encapsulates the computer vision library OpenCV at the highest level, integrates Accelera's System-C/TLM with UVM and QEMU-OS …


Principal Component Analysis And Optimization: A Tutorial, Robert Reris, J. Paul Brooks Jan 2015

Principal Component Analysis And Optimization: A Tutorial, Robert Reris, J. Paul Brooks

Statistical Sciences and Operations Research Publications

No abstract provided.


Effective Auto Encoder For Unsupervised Sparse Representation, Faria Mahnaz Jan 2015

Effective Auto Encoder For Unsupervised Sparse Representation, Faria Mahnaz

Wayne State University Theses

High dimensionality and the sheer size of unlabeled data available today demand

new development in unsupervised learning of sparse representation. Despite of recent

advances in representation learning, most of the current methods are limited when

dealing with large scale unlabeled data. In this study, we propose a new unsupervised

method that is able to learn sparse representation from unlabeled data efficiently. We

derive a closed-form solution based on the sequential minimal optimization (SMO)

for training an auto encoder-decoder module, which efficiently extracts sparse and

compact features from any data set with various size. The inference process in the

proposed learning …


The Impact Of Increased Optimization Problem Dimensionality On Cultural Algorithm Performance, Yang Yang Jan 2015

The Impact Of Increased Optimization Problem Dimensionality On Cultural Algorithm Performance, Yang Yang

Wayne State University Theses

ABSTRACT

The Impact of Increased Optimization Problem Dimensionality on

Cultural Algorithm Performance

by

Yang Yang

August 2015

Advisor: Dr. Robert Reynolds

Major: Computer Science

Degree: Master of Science

In this thesis, we investigate the performance of Cultural Algorithms when dealing with the increasing dimensionality of optimization problems. The research is based on previous cultural algorithm approaches with the Cultural Algorithms Toolkit, CAT 2.0, which supports a variety of co-evolutionary features at both the knowledge and population levels. In this project, the system was applied to the solution of 60 randomly generated problems that ranged from 2-dimensional to 5-dimensional problem spaces. …


Contributions To The Solution Of Large Nonlinear Systems Via Model-Order Reduction And Interval Constraint Solving Techniques, Leobardo Valera Jan 2015

Contributions To The Solution Of Large Nonlinear Systems Via Model-Order Reduction And Interval Constraint Solving Techniques, Leobardo Valera

Open Access Theses & Dissertations

Many engineering problems boil down to solving partial differential equations (PDEs) that describe real-life phenomena. Nevertheless, efficiently and reliably solving such problems constitutes a major challenge in computational sciences and in engineering in general.

PDE-based systems can reach sizes so large after they are discretized. The large size in these problems generate several issues, among them we can mention: large space of storing, computing time, and the most important, lost of accuracy. A popular approach to solving such problems is assume that the PDE's solution is in a subspace, and the solution is sought there. This assumption and later searching …


Shape Optimization For Drag Minimization Using The Navier-Stokes Equation, Chukwudi Paul Chukwudozie Jan 2015

Shape Optimization For Drag Minimization Using The Navier-Stokes Equation, Chukwudi Paul Chukwudozie

LSU Master's Theses

Fluid drag is a force that opposes relative motion between fluid layers or between solids and surrounding fluids. For a stationary solid in a moving fluid, it is the amount of force necessary to keep the object stationary in the moving fluid. In addition to fluid and flow conditions, pressure drag on a solid object is dependent on the size and shape of the object. The aim of this project is to compute the shape of a stationary 2D object of size 3.5 m2 that minimizes drag for different Reynolds numbers. We solve the problem in the context of shape …


Constrained Optimization Of Average Arrival Time Via A Probabilistic Approach To Transport Reliability, Mohammad-Reza Namazi-Rad, Michelle E. Dunbar, Hadi Ghaderi, Payam Mokhtarian Jan 2015

Constrained Optimization Of Average Arrival Time Via A Probabilistic Approach To Transport Reliability, Mohammad-Reza Namazi-Rad, Michelle E. Dunbar, Hadi Ghaderi, Payam Mokhtarian

SMART Infrastructure Facility - Papers

To achieve greater transit-time reduction and improvement in reliability of transport services, there is an increasing need to assist transport planners in understanding the value of punctuality; i.e. the potential improvements, not only to service quality and the consumer but also to the actual profitability of the service. In order for this to be achieved, it is important to understand the network-specific aspects that affect both the ability to decrease transit-time, and the associated cost-benefit of doing so. In this paper, we outline a framework for evaluating the effectiveness of proposed changes to average transit-time, so as to determine the …


Improving Processing By Adaption To Conditional Geostatistical Simulation Of Block Compositions, R. Tolosana-Delgado, Ute A. Mueller, K. G. Van Den Boogaart, C. Ward, J. Gutzmer Jan 2015

Improving Processing By Adaption To Conditional Geostatistical Simulation Of Block Compositions, R. Tolosana-Delgado, Ute A. Mueller, K. G. Van Den Boogaart, C. Ward, J. Gutzmer

Research outputs 2014 to 2021

Exploitation of an ore deposit can be optimized by adapting the beneficiation processes to the properties of individual ore blocks. This can involve switching in and out certain treatment steps, or setting their controlling parameters. Optimizing this set of decisions requires the full conditional distribution of all relevant physical parameters and chemical attributes of the feed, including concentration of value elements and abundance of penalty elements. As a first step towards adaptive processing, the mapping of adaptive decisions is explored based on the composition, in value and penalty elements, of the selective mining units. Conditional distributions at block support are …


The Supply Chain Of Fair Trade Coffee: Challenges, Opportunities & The Future Inside A Troubled Industry, Katharine D. Lukas Jan 2015

The Supply Chain Of Fair Trade Coffee: Challenges, Opportunities & The Future Inside A Troubled Industry, Katharine D. Lukas

Graduate College Dissertations and Theses

What started as a grassroots effort to aid tradespeople in developing nations, Fair Trade and similar certification models have, over the last sixty years, successfully established themselves as a viable alternative to conventional international trade; the ongoing growth of their market share and volume emphasize the increasing market demand for these alternatives. For coffee, Fair Trade's oldest and most established commodity, over two billion pounds was sold as certified in 2012 alone and the percentage of certified coffee continues to grow in share each year (Volcafe, 2012, Fair Trade USA 2012). As Fair Trade continues to grow, so does the …


Mathematical Modeling For Platform-Based Product Configuration Considering Total Life-Cycle Sustainability, Tian Lan Jan 2015

Mathematical Modeling For Platform-Based Product Configuration Considering Total Life-Cycle Sustainability, Tian Lan

Theses and Dissertations--Mechanical Engineering

Many companies are using platform-based product designs to fulfill the requirements of customers while maintaining low cost. However, research that integrates sustainability into platform-based product design is still limited. Considering sustainability during platform-based design process is a challenge because the total life-cycle from pre-manufacturing, manufacturing and use to post-use stages as well as economic, environmental and societal performance in these stages must be considered. In this research, an approach for quantifying sustainability is introduced and a mathematical model is developed for identifying a more sustainable platform. Data from life-cycle assessment is used to quantify environmental factors; criteria from the Product …


Optimization Schemes For The Inversion Of Bouguer Gravity Anomalies, Azucena Zamora Jan 2015

Optimization Schemes For The Inversion Of Bouguer Gravity Anomalies, Azucena Zamora

Open Access Theses & Dissertations

Data sets obtained from measurable physical properties of the Earth structure have helped advance the understanding of its tectonic and structural processes and constitute key elements for resource prospecting. 2-Dimensional (2-D) and 3-D models obtained from the inversion of geophysical data sets are widely used to represent the structural composition of the Earth based on physical properties such as density, seismic wave velocities, magnetic susceptibility, conductivity, and resistivity. The inversion of each one of these data sets provides structural models whose consistency depends on the data collection process, methodology, and overall assumptions made in their individual mathematical processes. Although sampling …


Superior Decoupled Control Of Active And Reactive Power For Three-Phase Voltage Source Converters, Hesam Rahbarimagham, Erfan Maali Amiri, Behrooz Vahidi, Gevorg Babamalek Gharehpetian, Mehrdad Abedi Jan 2015

Superior Decoupled Control Of Active And Reactive Power For Three-Phase Voltage Source Converters, Hesam Rahbarimagham, Erfan Maali Amiri, Behrooz Vahidi, Gevorg Babamalek Gharehpetian, Mehrdad Abedi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an active-reactive power control strategy for voltage source converters (VSCs) based on derivation of the direct and quadrature components of the VSC output current. The proposed method utilizes a multivariable proportional-integral controller and provides almost completely decoupled control capability of the active and reactive power with almost full disturbance rejection due to step changes in the power exchanged between the VSC and the grid. It also imposes fast transient response and zero steady-state error as compared to the conventional power control approaches. The applicability of the proposed power control strategy for providing the robust stability of the …


Determination Of Electromagnetic Properties Of Steel For Prediction Of Stray Losses In Power Transformers, Leonardo Strac, Damir Zarko Jan 2015

Determination Of Electromagnetic Properties Of Steel For Prediction Of Stray Losses In Power Transformers, Leonardo Strac, Damir Zarko

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces a method for determination of equivalent linear electromagnetic parameters (constant complex permeability and electrical conductivity) of nonlinear magnetic steel, which can be used in a time-harmonic finite-element simulation to yield the same losses in the volume of that material as the measured ones. The conductivity and the static hysteresis loop of the steel have been measured, from which complex permeability as a function of flux density has been extracted. The indirect measurement of losses in various samples of nonmagnetic and magnetic steel has been carried out using a physical model of a transformer core with a coil. …


A Framework And System For A Multi-Model Decision Aid For Sustainable Farming Practices, Kasi Bharath Vegesana Jan 2015

A Framework And System For A Multi-Model Decision Aid For Sustainable Farming Practices, Kasi Bharath Vegesana

Computational Modeling & Simulation Engineering Theses & Dissertations

Decision support systems (DSS) for farmers address the need for modeling multiple processes and scenarios that affect farmer decision making. Existing DSS have various drawbacks that stop them from being deployed as decision support tools. This research proposes a multi-model simulation framework that can be used to analyze farm management practices at the crop level, individual farm level and at the community level to show the impact and alternatives for smallholder farming practices. A generic crop growth model is proposed, based on existing equations. We run sensitivity analysis on the model to identify important variables. The outputs from the crop …


An Optimization Method For Estimating Joint Parameters Of The Hip And Knee, Ben Tesch Dec 2014

An Optimization Method For Estimating Joint Parameters Of The Hip And Knee, Ben Tesch

Theses and Dissertations

Biomechanics, generally speaking, concerns the application of engineeringprinciples to the study of living things. This work is concerned withhuman movement analysis, a subfield of biomechanics, where the methodsof classical mechanics are applied to human movement. This field hascontributed to the general understanding of human movement, and itstechniques are used in the diagnosis and treatment of disease. Centralto the field is the process of measuring human movement. Since classicalmechanics deals with the motion of rigid bodies, and ideal measurementsystem would be able to accurately record the exact pose --- combinedposition and orientation --- of the bones. The techniques that reachthis ideal …


Truckload Shipment Planning And Procurement, Neo Nguyen Dec 2014

Truckload Shipment Planning And Procurement, Neo Nguyen

Graduate Theses and Dissertations

This dissertation presents three issues encountered by a shipper in the context of truckload transportation. In all of the studies, we utilize optimization techniques to model and solve the problems. Each study is inspired from the real world and much of the data used in the experiments is real data or representative of real data.

The first topic is about the freight consolidation in truckload transportation. We integrate it with a purchase incentive program to increase truckload utilization and maximize profit. The second topic is about supporting decision making collaboration among departments of a manufacturer. It is a bi-objective optimization …


High Dimensional Non-Linear Optimization Of Molecular Models, Joseph C. Fogarty Nov 2014

High Dimensional Non-Linear Optimization Of Molecular Models, Joseph C. Fogarty

USF Tampa Graduate Theses and Dissertations

Molecular models allow computer simulations to predict the microscopic properties of macroscopic systems. Molecular modeling can also provide a fully understood test system for the application of theoretical methods. The power of a model lies in the accuracy of the parameter values which govern its mathematical behavior. In this work, a new software, called ParOpt, for general high dimensional non-linear optimization will be presented. The software provides a very general framework for the optimization of a wide variety of parameter sets. The software is especially powerful when applied to the difficult task of molecular model parameter optimization. Three applications of …


Concept Of Online Assisted Platform For Technologies And Management In Communications – Optimek, Galia Marinova, Vassil Guliashki, Ognyan Chikov Nov 2014

Concept Of Online Assisted Platform For Technologies And Management In Communications – Optimek, Galia Marinova, Vassil Guliashki, Ognyan Chikov

UBT International Conference

The paper describes the concept of a Multimodular Multydisciplinary platform, contacting through unified templates in a Portal with knowledge, with Useful INTERNET resources, in order to provide advanced research and education. Usually the online resources available are mainly in the area of e- and distance education, but still an understanding is missing for the scale and the use of studying and the systematization of the online resource. The new concept has an accent of the useful INTERNET resource and the development of a System of nets to it, in the aim of solving tasks and generating new knowledge in the …


Scalable Tuning Of Building Models To Hourly Data, Aaron Garrett, Joshua New Oct 2014

Scalable Tuning Of Building Models To Hourly Data, Aaron Garrett, Joshua New

Research, Publications & Creative Work

Energy models of existing buildings are unreliable unless calibrated so that they correlate well with actual energy usage. Manual tuning requires a skilled professional and is prohibitively expensive for small projects, imperfect, nonrepeatable, and not scalable to the dozens of sensor channels that smart meters, smart appliances, and sensors are making available. A scalable, automated methodology is needed to quickly, intelligently calibrate building energy models to all available data, increase the usefulness of those models, and facilitate speed-and-scale penetration of simulation-based capabilities into the marketplace for actualized energy savings. The "Autotune" project is a novel, model-agnostic methodology that leverages supercomputing, …


Optimization Of Switch Virtual Keyboard By Using Computational Modelling, Xiao Zhang Oct 2014

Optimization Of Switch Virtual Keyboard By Using Computational Modelling, Xiao Zhang

Open Access Theses

In this thesis, I first reviewed some keyboard technologies used by people with motor difficulties, and described design elements that influence efficiency. I cast the design of a switch keyboard as an optimization problem, and arrangement of keys on such a keyboard as a Mixed Integer Programming problem. One significant variable in the MIP problem, the error rate, is related to several other variables. I treated modeling of the error rate as a parameter estimation problem, and used a data mining method. I designed HCI experiments to gather data for parameter estimation, using Bayesian logistic regression model. The empirical data …


Optimal Contract Design For Co-Development Of Companion Diagnostics, Rodney T. Tembo Sep 2014

Optimal Contract Design For Co-Development Of Companion Diagnostics, Rodney T. Tembo

Electronic Thesis and Dissertation Repository

As the number of new drugs requiring companion diagnostics rises, more and more partnerships are formed between drug and diagnostics manufacturers to develop the necessary companion diagnostic. An increasingly significant issue is that of the optimal revenue/profit sharing or compensation schemes for such partnerships. We investigate the structure of an optimal compensation scheme under a scenario where a large pharmaceutical firm that is developing a drug intends to partner with a smaller diagnostics firm to develop a companion diagnostic test for the drug. We describe an optimal contract as one that maximizes the pharmaceutical firm's expected profits while offering enough …


Optimizing Bio-Retention Locations For Stormwater Management Using Genetic Algorithm, Dieu Huong Trinh, Ting Fong May Chui Aug 2014

Optimizing Bio-Retention Locations For Stormwater Management Using Genetic Algorithm, Dieu Huong Trinh, Ting Fong May Chui

International Conference on Hydroinformatics

To minimize the change of hydrological regime due to urbanization, stormwater best management practices have been enforced in the past few decades in certain urban areas. One approach is to implement small-scale hydrologic controls, such as bio-retention systems, throughout a catchment. Optimization techniques have also been applied to determine the locations that give the most hydrological benefits. However, optimization tools are commonly built in together with specific hydrological models. Thus, the choices and components of hydrological models are usually restricted. Furthermore, it is redundant to build another hydrological model that has a built-in optimization tool if a hydrological model, and …


Real-Time Water Decision Support Services For Droughts, Tingting Zhao, Barbara Minsker, Jong Lee, Fernando Salas, David R. Maidment, Cedric David Aug 2014

Real-Time Water Decision Support Services For Droughts, Tingting Zhao, Barbara Minsker, Jong Lee, Fernando Salas, David R. Maidment, Cedric David

International Conference on Hydroinformatics

Through application of computational methods and an integrated information system, real-time data and river modeling systems can help decision makers identify more effective actions for management practice. The purpose of this study is to develop a real-time decision support model to recommend optimal curtailments during water shortages for decision makers. To enable ease of use and re-use, the workflows (i.e., analysis and model steps) of the real-time decision support model are published as Web services delivered through an internet browser, including model inputs, a published workflow service, and visualized outputs. The model consists of two major components: the real-time river …


Parameter Calibration Method Based On Ga Technique For Multi-Event, Yeonjoo Kim, Eun-Sung Chung, Kwangjai Won, Byungho Kong, Kyungil Gil Aug 2014

Parameter Calibration Method Based On Ga Technique For Multi-Event, Yeonjoo Kim, Eun-Sung Chung, Kwangjai Won, Byungho Kong, Kyungil Gil

International Conference on Hydroinformatics

Accurate parameter estimation based catchment modeling systems requires considerable work to establish credibility. In this paper, a methodology for parameter estimation of hydrologic simulation model is proposed to simultaneously include several rainfall events using Shannon entropy. The proposed methodology uses Genetic Algorithm(GA) optimization techniques for the Storm Water Management Model (SWMM). Shannon entropy theory was applied to calculate weights according to each rainfall event in study area. A case study application was undertaken using the Milyang-dam basin, in Korea. Three events are applied to calculate Shannon entropy weights. Then, Nash-Sutcliffe Efficiency(NSE) & Root Mean Square Error(RMSE) are compared with those …


Short-Term Optimization Model With Esp Forecasts For Columbia Hydropower System With Optimized Multi-Turbine Powerhouses, Jery R. Stedinger, Sue Nee Tan, Christine A. Shoemaker, Jonathan R. Lamontagne, Steven B. Barton Aug 2014

Short-Term Optimization Model With Esp Forecasts For Columbia Hydropower System With Optimized Multi-Turbine Powerhouses, Jery R. Stedinger, Sue Nee Tan, Christine A. Shoemaker, Jonathan R. Lamontagne, Steven B. Barton

International Conference on Hydroinformatics

Hydroelectric generation is the major source of electric energy in the Pacific Northwestern region of the United States, and efficient operation of that system while meeting environmental constraints and reserve capacity demands is an important economic, environmental, and social issue. This paper describes efforts to develop a new stochastic short-term scheduling model (with perhaps a 3-week planning horizon) for the ten major reservoirs operated by the federal Bonneville Power Administration (BPA) on the Columbia and Snake River systems. The analysis incorporates time-delays (up to 24 hours in a model with time steps increasing from 6 hours initially perhaps to 24 …


Optimized Use Of Water From Multiple Sources In Micro Water Grid Systems: A Modeling Approach, Hyeongrak Cho, Jungwoo Jung, Sangho Lee, Soo Kwen Chae Aug 2014

Optimized Use Of Water From Multiple Sources In Micro Water Grid Systems: A Modeling Approach, Hyeongrak Cho, Jungwoo Jung, Sangho Lee, Soo Kwen Chae

International Conference on Hydroinformatics

Micro water grid (MWG) is a novel approach to allow high reliability, diversification of water sources, low energy consumption, and cost reduction. Although it is not well-defined, it has potential for efficient management of urban water. MWG is suitable for use in small-scale buildings and towns, which have various uses of water produced from multiple source waters. Accordingly, design of MWG is challenging without proper tools to predict its performance. This research focused on the development and application of a model for optimized use of water from multiple sources in MWG systems. The model was comprised of two modules including …


A Hybrid Optimization Method For Real-Time Pump-Scheduling, Valeria Puleo, Mark Morley, Gabriele Freni, Dragan A. Savić Aug 2014

A Hybrid Optimization Method For Real-Time Pump-Scheduling, Valeria Puleo, Mark Morley, Gabriele Freni, Dragan A. Savić

International Conference on Hydroinformatics

Linear, non-linear and dynamic programming, heuristics and evolutionary computation are amongst the techniques which have been applied to obtain solutions to optimal pump-scheduling problems. Most of these either greatly simplify the complex water distribution system or require significant time to solve the problem. The scheduling of pumps is frequently undertaken in near-real time, in order to minimize cost and maximize energy savings. However, this requires a computationally efficient algorithm that can rapidly identify an acceptable solution. In this paper, a hybrid optimization model is presented, coupling Linear Programming and Genetic Algorithms. The resulting hybrid optimization model has demonstrated more rapid …


Optimal Rehabilitation Strategy In Water Distribution Systems Considering Reduction In Greenhouse Gas Emissions, Farshid Rahmani, Abdollah Ardeshir, Kourosh Behzadian, Fatemeh Jalilsani Aug 2014

Optimal Rehabilitation Strategy In Water Distribution Systems Considering Reduction In Greenhouse Gas Emissions, Farshid Rahmani, Abdollah Ardeshir, Kourosh Behzadian, Fatemeh Jalilsani

International Conference on Hydroinformatics

Most of water distribution systems (WDS) need rehabilitation due to aging infrastructure leading to decreasing capacity, increasing leakage and consequently low performance of the WDS. However an appropriate strategy including location and time of pipeline rehabilitation in a WDS with respect to a limited budget is the main challenge which has been addressed frequently by researchers and practitioners. On the other hand, selection of appropriate rehabilitation technique and material types is another main issue which has yet to address properly. The latter can affect the environmental impacts of a rehabilitation strategy meeting the challenges of global warming mitigation and consequent …


Real-Time Reservoir Operation For Drought Management Considering Ensemble Streamflow Predictions Derived From Operational Forecasts Of Precipitation In Japan, Daisuke Nohara, Tomoharu Hori Aug 2014

Real-Time Reservoir Operation For Drought Management Considering Ensemble Streamflow Predictions Derived From Operational Forecasts Of Precipitation In Japan, Daisuke Nohara, Tomoharu Hori

International Conference on Hydroinformatics

Ensemble hydrological predictions are considered to be useful for robust reservoir operation as they include multiple possible hydrological scenarios in the future as well as dispersion of the predictions, from which the degree of prediction uncertainty can be estimated. Although operational ensemble hydrological predictions have been available in many regions, they have not yet been widely used in the actual reservoir management due to the difficulty in the handling such complex information. In order to facilitate effective utilization of ensemble hydrological predictions in the actual reservoir management, a real-time reservoir operation method for drought management is developed considering operational ensemble …


Short-Term Optimization Of A Canal Network For Navigation And Water Management, Arnejan Van Loenen, Min Xu, Robin Engel Aug 2014

Short-Term Optimization Of A Canal Network For Navigation And Water Management, Arnejan Van Loenen, Min Xu, Robin Engel

International Conference on Hydroinformatics

We present the design, implementation and operational use of a short-term optimization approach for the operational water management of the Twentekanalen canal system for navigation and water resources management. The system was originally designed for navigation and its construction had been completed in 1938. In the past decades, it also became increasingly important for the regional water management. In summer periods, the system provides the region with fresh water and helps to drain the area otherwise. The short-term optimization is implemented in the Operational Monitoring System for the National Regulated Water Systems for advising the operating staff on the operation …