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2012

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On-Line Transient Stability Studies Incorporating Wind Power, Zhenhua Wang Dec 2012

On-Line Transient Stability Studies Incorporating Wind Power, Zhenhua Wang

All Dissertations

Transient stability is a major concern in power system security and reliability because it is the most common type of instability and its impacts can cause greatest economic losses. For enhancing the energy security, it requires the power system operation to be evaluated during both the planning and the operation stage. Many online/offline transient stability assessment techniques have already been developed for this purpose. However, due to the increase in energy demand, the modern power system has grown to a very sophisticated and large system for which extent transient stability assessment methods may not be able to handle. In addition, …

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Improving Accuracy In Ultra-Wideband Indoor Position Tracking Through Noise Modeling And Augmentation, Salil Banerjee Dec 2012

Improving Accuracy In Ultra-Wideband Indoor Position Tracking Through Noise Modeling And Augmentation, Salil Banerjee

All Dissertations

The goal of this research is to improve the precision in tracking of an ultra-wideband (UWB) based Local Positioning System (LPS). This work is motivated by the approach taken to improve the accuracies in the Global Positioning System (GPS), through noise modeling and augmentation. Since UWB indoor position tracking is accomplished using methods similar to that of the GPS, the same two general approaches can be used to improve accuracy.
Trilateration calculations are affected by errors in distance measurements from the set of fixed points to the object of interest. When these errors are systemic, each distinct set of fixed …

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The Behavior And Toxicity Of Metal Oxide Nanoparticles In Aqueous Solution, Phenny Mwaanga Dec 2012

The Behavior And Toxicity Of Metal Oxide Nanoparticles In Aqueous Solution, Phenny Mwaanga

All Dissertations

The dissolution and aggregation of metal oxides nanoparticles (NPs) in aqueous solution not only alter the abundance and toxicology of NPs, but also makes the effective assessment and the correct interpretation of effects of NPs on organisms challenging. The extent to which these processes (dissolution and aggregation) occur largely depend on pH, ionic strength, dissolved natural organic matter (NOM) and NPs characteristics. This study investigated the dissolution and aggregation behavior of the four metal oxide NPs (nZnO, nCuO, nFe2O3 and nTiO2) in aqueous solution as influenced by pH, ionic strength and NOM and examined the toxicity of these NPs to …

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Dynamic And Static Effects In Wetting Of Capillaries And Fibers, Taras Andrukh Dec 2012

Dynamic And Static Effects In Wetting Of Capillaries And Fibers, Taras Andrukh

All Dissertations

This research is centered on the analysis of static and dynamic effects of wetting of single capillaries and fibers. We discuss specifics of the capillary rise and drop-on-fiber techniques and develop new methods of characterization of surface energy of single fibers when its contact angle varies between zero and ninety degrees. The contact angles were evaluated and compared for different substrates. We study the dynamics of the meniscus formation inside and outside of capillaries and fibers. We develop a mathematical model of liquid uptake by capillaries and analyze the factors affecting liquid uptake. The derived fundamental equation describes the dynamics …

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Fate And Reactivity Of Natural And Manufactured Nanoparticles In Soil/Water Environments, Allison Vandevoort Dec 2012

Fate And Reactivity Of Natural And Manufactured Nanoparticles In Soil/Water Environments, Allison Vandevoort

All Dissertations

Nanoparticles (NPs), < 100 nm in diameter, make up the smallest component of solid material. This small size often causes increased reactivity in soil/water environments, which is true for both natural NPs, such as very fine clay particles, and for manufactured nanoparticles, such as silver nanoparticles (AgNPs). As the importance of these particles is more widely recognized, and as manufactured nanoparticles, especially AgNPs, are increasing in production, it is essential to consider their effect on terrestrial and aquatic environments. The studies presented in this dissertation show that both the physicochemical characteristics of the NPs (e.g., particle size, surface coating, elemental composition), as well as soil-water interfacial chemistry (e.g., ionic strength, ligand concentration, pH), are instrumental in predicting environmental fate and reactivity.
Ligand type and concentration were especially important in NP reactivity and bioavailability. Using the hard/soft acid/base concept, the effect of phosphate ligand (hard base) on Fe/Al (hard acid) oxyhydroxide natural NPs was investigated in Chapters 2 and 3. Adding phosphate to soil NPs and reference nano-minerals (Fe-(oxyhydr)oxides and kaolinite) caused coagulation or dispersion, changing the particle size of the NPs, as well as affecting the amount of phosphate in its bioavailable (i.e., dissolved) form. A review of the literature in Chapters 1 and 3 revealed that changes in the soil conditions, and therefore, soil colloids/NPs (e.g., increasing organic …

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Solvation Energy Of Biomolecular Structures: A Study Of The Effect Of Salt On Biomolecules Through Implicit As Well As Explicit Solvation Methods, Mihir Date Dec 2012

Solvation Energy Of Biomolecular Structures: A Study Of The Effect Of Salt On Biomolecules Through Implicit As Well As Explicit Solvation Methods, Mihir Date

All Dissertations

In the current dissertation, studies related to solvation energy of protein structures using implicit as well explicit solvation methods have been discussed. Special focus is given to explore effect of salt on the fold stability of proteins and enzymes. Salt plays a crucial role in the functioning of all proteins, enzymes and nucleic acids. Change in salt concentration of the medium has large impact on stability and activity of these biological macromolecules. Therefore exploring mechanism of salt effect on them and development of an efficient model to calculate the salt effect has fundamental as well as practical importance in the …

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Photo-Thermal Processing Of Semiconductor Fibers And Thin Films, Nishant Gupta Dec 2012

Photo-Thermal Processing Of Semiconductor Fibers And Thin Films, Nishant Gupta

All Dissertations

Furnace processing and rapid thermal processing (RTP) have been an integral part of several processing steps in semiconductor manufacturing. The performance of RTP techniques can be improved many times by exploiting quantum photo-effects of UV and vacuum ultraviolet (VUV) photons in thermal processing and this technique is known as rapid photo-thermal processing (RPP). As compared to furnace processing and RTP, RPP provides higher diffusion coefficient, lower stress and lower microscopic defects. In this work, a custom designed automated photo assisted processing system was built from individual parts and an incoherent light source. This photo-assisted processing system is used to anneal …

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Spectroscopic Signature For Bundling, Edge States And Impurities In 1d And 0d Materials, Kiran Kumar Lingam Dec 2012

Spectroscopic Signature For Bundling, Edge States And Impurities In 1d And 0d Materials, Kiran Kumar Lingam

All Dissertations

Study of nanomaterials has gained interest of researchers from various fields of science and technology due to their unique electronic and vibrational properties as compared to their bulk counterparts. In particular, carbon nanotechnology has evolved rapidly over the past few decades and nowadays, carbon nanotubes are used in various fields such as energy storage, electronics etc. However, the quest for new properties of this material is never ending and the invention of graphene generated enormous interest in the scientific community due to its excellent properties such as strength, high electron mobility, thermal conductivity etc. In this thesis, I aim at …

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Towards Trustworthy, Efficient And Scalable Distributed Wireless Systems, Ze Li Dec 2012

Towards Trustworthy, Efficient And Scalable Distributed Wireless Systems, Ze Li

All Dissertations

Advances in wireless technologies have enabled distributed mobile devices to connect with each other to form distributed wireless systems. Due to the absence of infrastructure, distributed wireless systems require node cooperation in multi-hop routing. However, the openness and decentralized nature of distributed wireless systems where each node labors under a resource constraint introduces three challenges: (1) cooperation incentives that effectively encourage nodes to offer services and thwart the intentions of selfish and malicious nodes, (2) cooperation incentives that are efficient to deploy, use and maintain, and (3) routing to efficiently deliver messages with less overhead and lower delay. While most …

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A Case Study In Collaborative Efforts At Spartanburg Community College, Frederick Cooper Dec 2012

A Case Study In Collaborative Efforts At Spartanburg Community College, Frederick Cooper

All Dissertations

The General Assembly of South Carolina radically changed the structure of secondary education with the enactment of the Education and Economic Development Act (EEDA) of 2005. A provision in the legislation requires post-secondary institutions to develop articulation agreements with secondary institutions in their service area(s). Traditionally, articulation agreements between secondary and post-secondary institutions have been few and far between. The question then becomes how articulation agreements are developed from the post-secondary perspective. Spartanburg Community College is one of the sixteen technical/community colleges in South Carolina. The development of articulation agreements is examined at Spartanburg Community College using the lens of …

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Sample Preparation Techniques For The Improvement Of Analytical Measurements: Capillary-Channeled Polymer Fibers Employed In Protein Solid Phase Extraction Applications And Characterization Of Active Components In Botanical Dietary Supplements, Carolyn Burdette Dec 2012

Sample Preparation Techniques For The Improvement Of Analytical Measurements: Capillary-Channeled Polymer Fibers Employed In Protein Solid Phase Extraction Applications And Characterization Of Active Components In Botanical Dietary Supplements, Carolyn Burdette

All Dissertations

The task of sample preparation encompasses many challenges and demands for analytical techniques. Appropriate preparative steps can be the determining factor between successful measurements and failures. Too little preparation can lead to the inability to detect analytes due to low concentrations, insufficient extraction of analytes, and/or strong matrix effects; exhaustive preparation steps increases analysis times, the potential for analyte losses, and the difficulty to obtain consistent reproducible results. Discussed here are several examples of analytical techniques where sample preparation is critical and can be used to improve existing techniques. Capillary-channeled polymer (C-CP) fibers used for solid phase extraction (SPE) protein …

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Sorption And Enantiomerization Of Current Use Chiral Pesticides, April Hall Dec 2012

Sorption And Enantiomerization Of Current Use Chiral Pesticides, April Hall

All Dissertations

Chiral pesticides are prevalent in the environment today and are known to react selectively with chiral environmental components such as microbes, enzymes, and other naturally occurring chiral materials. In addition, chiral sorption is a process that has been occasionally investigated in the study of homochirality (the exclusive presence of one enantiomer in living organisms), but almost overlooked in environmental science. For chiral sorption to occur, the sorbent and sorbate must be chiral entities. In the environment, there are abundant natural surfaces that are chiral, including clay minerals and organic matter present in soil, sediment and aqueous solution. A knowledge of …

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Integrated Production And Distribution Problem With Single Perishable Product, Wennian Li Dec 2012

Integrated Production And Distribution Problem With Single Perishable Product, Wennian Li

All Dissertations

This dissertation investigated the extension of the Integrated Production and Distribution Scheduling Problem (IPDSPP) using a variety of perishable products, applying the JIP principle and make-to-order strategy to integrate the production and distribution schedules. A single perishable product with a constant lifetime after production was used in the model discussed here. The objective of the problem was to find the solution that results in minimal system total transportation costs while satisfying customer demand within a fixed time horizon. In the solution, the fleet size, vehicle route and distribution schedule, plant production batch size and schedule were determined simultaneously. This research …

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Spider Mediation Of Polychlorinated Biphenyl Transport And Transformation Across Riparian Ecotones, Diana Delach Dec 2012

Spider Mediation Of Polychlorinated Biphenyl Transport And Transformation Across Riparian Ecotones, Diana Delach

All Dissertations

Polychlorinated biphenyls (PCBs) contaminate the sediment of the Twelvemile Creek / Lake Hartwell Superfund Site, and are known to be transported throughout the resident biota via trophic transport. Riparian spiders have recently become of interest because they are terrestrial organisms that have significant PCB exposures derived from aquatic sources. Many riparian spiders primarily consume insects emerging from contaminated aquatic systems, and these spiders can have a body burden as high as 2900 ng/g lipid. These emergent insects carry contaminants out of the river and into the riparian zone where they are captured by spiders, which effectively directs the contamination towards …

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Develop Novel Frap Techniques For Determining Anisotropic Solute Diffusion In Cartilaginous Tissues, Changcheng Shi Dec 2012

Develop Novel Frap Techniques For Determining Anisotropic Solute Diffusion In Cartilaginous Tissues, Changcheng Shi

All Dissertations

Cartilaginous tissue is a connective tissue composed of specialized cells (e.g., chondrocytes and fibroblasts) that produce a large amount of extracellular matrix (ECM), which is comprised mostly of collagen fibers, abundant ground substance rich in proteoglycan, and elastic fibers. It is characterized by its avascular structures within the tissue, implying that nutrition for normal tissue cells, for maintaining a healthy ECM, is mainly supplied through diffusion from nearby vascularized tissues and synovial fluid. Poor nutritional supply to the cartilaginous tissue is believed to be an important factor leading to tissue degeneration. Moreover, due to the complex collagen fiber structures, the …

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Polyhedral Approximations Of Quadratic Semi-Assignment Problems, Disjunctive Programs, And Base-2 Expansions Of Integer Variables, Frank Muldoon Dec 2012

Polyhedral Approximations Of Quadratic Semi-Assignment Problems, Disjunctive Programs, And Base-2 Expansions Of Integer Variables, Frank Muldoon

All Dissertations

This research is concerned with developing improved representations for special families of mixed-discrete programming problems. Such problems can typically be modeled using different mathematical forms, and the representation employed can greatly influence the problem's ability to be solved. Generally speaking, it is desired to obtain mixed 0-1 linear forms whose continuous relaxations provide tight polyhedral outer-approximations to the convex hulls of feasible solutions. This dissertation makes contributions to three distinct problems, providing new forms that improve upon published works.
The first emphasis is on devising solution procedures for the classical quadratic semi-assignment problem(QSAP), which is an NP-hard 0-1 quadratic program. …

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Understanding Nanoparticle-Cell Interaction, Ran Chen Dec 2012

Understanding Nanoparticle-Cell Interaction, Ran Chen

All Dissertations

Nanotechnology has revolutionalized the landscape of modern science and technology, including materials, electronics, therapeutics, bioimaging, sensing, and the environment. Along with these technological advancements, there arises a concern that engineered nanomaterials, owing to their high surface area and high reactivity, may exert adverse effects upon discharge to compromise biological and ecological systems. Research in the past decade has examined the fate of nanomaterials in vitro and in vivo, as well as the interactions between nanoparticles and biological and ecosystems using primarily toxicological and ecotoxicological approaches. However, due to the versatility in the physical and physicochemical properties of nanoparticles, and due …

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The Effects Of The Environmental Design Instruction On The Students' Gymnastics Skill Refinement, Han Chen Dec 2012

The Effects Of The Environmental Design Instruction On The Students' Gymnastics Skill Refinement, Han Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

The study compared the effects of Direct Instruction (DI) with DI+Environmental Design Instruction (EDI) on the refinement of both simple and difficult gymnastics skills refinement. Four boys aged six to eight with two years of gymnastics training experiences participated in the simple skill experiment (running tuck jump on the springboard). Four boys aged 11 to 13 with more than three years of gymnastics training experiences participated in the difficult skill experiment (mushroom circles). Three dependent variables were measured in the experiment of running tuck jump and they were: (1) the participant's hip angle while they jumped at the highest point, …

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Nnll Resummation For W-Boson Production At Large Pt, Nikolaos Kidonakis, Richard J. Gonsalves Dec 2012

Nnll Resummation For W-Boson Production At Large Pt, Nikolaos Kidonakis, Richard J. Gonsalves

Faculty Articles

We present new results for W-boson production at large transverse momentum at the LHC and the Tevatron. The contribution of soft-gluon corrections is derived from NNLL resummation and added to the exact NLO result. Numerical results and their uncertainties for the approximate NNLO W-boson transverse momentum distributions are derived and compared to recent data from the LHC.

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Optimization Models For Locating Cross-Docks Under Capacity Uncertainty, Anshul Soanpet Dec 2012

Optimization Models For Locating Cross-Docks Under Capacity Uncertainty, Anshul Soanpet

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this thesis is to develop mathematical models for locating cross-docks in a supply chain. Cross-docking is a strategy which can help consolidate the goods in the supply chain and save costs by reducing the number of truck trips. In this thesis four optimization models were developed. First two optimization models termed Model A and Model B were deterministic models. The goal of model A was to choose exactly P locations to locate cross-docks so that the transportation and handling costs are minimized. The goal of model B is to locate as many cross-docks as needed so that …

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Prospective Teachers' Comprehension Levels Of Special Relativity Theory And The Effect Of Writing For Learning On Achievement, Ali Yildiz Dec 2012

Prospective Teachers' Comprehension Levels Of Special Relativity Theory And The Effect Of Writing For Learning On Achievement, Ali Yildiz

Australian Journal of Teacher Education

In the present study, the comprehension levels of special relativity theory in prospective teachers who take the Introduction to Modern Physics lesson in the faculty of education science teaching department and the effect of writing for learning on their achievement is researched. In the research, a control group pre-test post-test quasi-experimental research model was used. Research data were obtained by using open-ended questions prepared by the researcher. The lesson was conducted in the beginning by using the verbal-written explanation method. Then each student in the experimental group wrote a summary which clearly explains the special relativity theory for a high …

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A Professional Experience Learning Community For Pre-Service Secondary Mathematics Teachers, Michael S. Cavanagh, Thomas Garvey Dec 2012

A Professional Experience Learning Community For Pre-Service Secondary Mathematics Teachers, Michael S. Cavanagh, Thomas Garvey

Australian Journal of Teacher Education

This paper reports the development and implementation of a collaborative professional experience learning community for a group of nine pre-service secondary mathematics teachers. The pre-service teachers and their methods lecturer made 12 school visits over one academic year to a local secondary school. The pre-service teachers observed and co-taught problem-solving lessons in two Year 8 classes. They discussed the lessons with the teacher and the university lecturer, and later posted reflective comments to an online forum. Data from questionnaires, interviews, and reflections indicate that participation in the learning community helped pre-service teachers make stronger links between theory and practice, learn …

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Computing Nodes And Links Appearances On Geodesics In Networks Topologies Using Graph Theory, Siddeeq Ameen, Laith Jasim Saud Dec 2012

Computing Nodes And Links Appearances On Geodesics In Networks Topologies Using Graph Theory, Siddeeq Ameen, Laith Jasim Saud

Iraqi Journal of Computers, Communications, Control and Systems Engineering

This paper proposes two important mathematical models related to network topology which helps in computing some of the efficiency or reliability factors of communication network as well as design purposes. Each of these models represents a topology property. The first (second) of these models is used to compute the number of appearances of any link (node) in the geodesics between nodes in a given network topology, and so can be used to help in uniformly distributing the data flow through links (nodes), as well as helping in measuring the degree of survivability of the network in case of failure of …

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Reward Effect In Reinforcement Learning Systems, Lubna Zaghlul, Zina Waleed Dec 2012

Reward Effect In Reinforcement Learning Systems, Lubna Zaghlul, Zina Waleed

Iraqi Journal of Computers, Communications, Control and Systems Engineering

Learning Classifier Systems (LCS), are a machine learning technique which combines reinforcement learning, eVolutionary computing and other heuristics to produce adaptive systems. The system HRC (Human – Rat - Cheese) focuses in creating artificial creature (Rat) using computer simulation, and learning it how to choose between two different basic behaviors, (approach / escape) combining them to perform complex behavior, which represents the final response in changing environment. The HRC is built of two-classifier subsystems working together, each classifier system learns a simple behavior, and the system as a whole has as its learning goal the control of activities. Flat architecture …

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Human Authentication With Earprint For Secure Telephone System, Raid R. Dec 2012

Human Authentication With Earprint For Secure Telephone System, Raid R.

Iraqi Journal of Computers, Communications, Control and Systems Engineering

This paper describes the design and development of a prototype system for the automatic authentication of an individual based on the human ear patterns. Information at the feature extraction and at the confidence level, where the matching scores are reported by Probabilistic neural network, is discussed. The system was tested with the template files. The test performance reaching False Rejection Rate (FRR) = 9% and False Acceptance Rate (FAR) = 9%, suggests that the system can be used in telephone security environments.

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Study Of The Influence Of Mechanical Parameters On The Behavior And Response Of Electromagnetic Servo Relay (Esr), Saad A-R., Ayad Ghazi Nasir Al-Shamary, Yaakob Karomy Hanna Dec 2012

Study Of The Influence Of Mechanical Parameters On The Behavior And Response Of Electromagnetic Servo Relay (Esr), Saad A-R., Ayad Ghazi Nasir Al-Shamary, Yaakob Karomy Hanna

Iraqi Journal of Computers, Communications, Control and Systems Engineering

The Relay is widely used in civil, industrial and military equipment. The Relay is considered to be one of the indispensable actuators for electric power and control flying objects and systems. Relays reliability strongly influences the system reliability. The mathematical model of the servo is introduced including the electrical, magnetic and dynamic parts. Simulations, using Matlab and Simulink, were performed. An improvement to the mathematical model has been carried through simulation which reflected on the results gained. Results of the effect and influence of magnetic materials and some important mechanical parameters like stiffness, viscosity, and copper insulator thickness, on the …

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Enhanced Genetic Algorithm Based On Node Codes For Mobile Robot Path Planning, Mohamed Jasim, Farah S. Khoshaba Dec 2012

Enhanced Genetic Algorithm Based On Node Codes For Mobile Robot Path Planning, Mohamed Jasim, Farah S. Khoshaba

Iraqi Journal of Computers, Communications, Control and Systems Engineering

In this paper, a new Enhanced Genetic Algorithm (EGA) is used to find the best global path planning for a mobile robot according to a specific criterion. The EGA is enhanced by a new encoding method, new initial population creation method, new crossover and mutation operations as well as new additional operations correction operation and classification operation. The study considers the case when the mobile robot works in a known static environment. The new proposed algorithm is built to help the mobile robot to choose the shortest path without it colliding with the obstacles allocated in a working known environment. …

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Design Of A Nonlinear Speed Controller For A Dc Motor System With Unknown External Torque Based On Backstepping Approach, Shibly Ahmed, Yasir Khudhair Abbas Dec 2012

Design Of A Nonlinear Speed Controller For A Dc Motor System With Unknown External Torque Based On Backstepping Approach, Shibly Ahmed, Yasir Khudhair Abbas

Iraqi Journal of Computers, Communications, Control and Systems Engineering

A nonlinear PI controller for a system with a mismatched and unknown external disturbance is proposed in the present paper. A Sigmoidal function is proposed to be used in the nonlinear integral element to attenuate the disturbance effect. Formally the controller forces the state to a positively invariant set around the origin. As an application, the nonlinear PI controller is used as a virtual controller for the upper subsystem in the frame of Backstepping control approach for the DC motor system. In this Backstepping controller design the restriction about the disturbance form in the upper system is relaxed. The results …

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Controlling A Nonlinear Servo Hydraulic System Using Pid Controller With A Genetic Algorithm Tool, Shaymaa Mahmood Dec 2012

Controlling A Nonlinear Servo Hydraulic System Using Pid Controller With A Genetic Algorithm Tool, Shaymaa Mahmood

Iraqi Journal of Computers, Communications, Control and Systems Engineering

The purpose of this paper is to present the modeling and simulation of a servo hydraulic system. Hydraulic systems are broadly used in the industry due to their ability to adapt to a wide range of purposes and their proven robustness. First we develop a mathematical model to obtain the system responses. These responses represent the response of the servo hydraulic system with a sinusoidal input. Secondly, we design a PID controller in order to improve the position transient response and reach minimum steady state error in the output displacement. Then, we use Genetic Algorithm technique to find the best …

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Design Of On-Line Tuned Idle Speed Controller For An Automotive Engine By Using Ncd, Ali Majeed Dec 2012

Design Of On-Line Tuned Idle Speed Controller For An Automotive Engine By Using Ncd, Ali Majeed

Iraqi Journal of Computers, Communications, Control and Systems Engineering

This paper attempts to tune any controller without the knowledge of mathematical model for the system to be controlled. For that purpose, the optimization algorithm of MATLAB / Nonlinear Control Design Blockset (NCD) is adapted for On-line tuning for controller parameters. To present the methodology, a PID controller is verified with the physical plant using the engine speed control System where the problem of maintaining the engine idle speed at a reference value with the applied load is studied. A Proportional Integral Derivative (PID) Controller is used to solve this problem, but to get the best controller parameters the (NCD) …

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