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Global Environmental Law: Food Safety & China, Jason J. Czarnezki Jan 2013

Global Environmental Law: Food Safety & China, Jason J. Czarnezki

Elisabeth Haub School of Law Faculty Publications

This article makes the case for food security law and policy as a component of global environmental law in recognition of the global economy, trade liberalization, and concerns for food safety and environmental harm. It further describes rule of law as a significant force in mitigating food safety concerns and pollution in China. Part II explores global food safety concerns in the context of United States-China relations, while Part III discusses the U.S. Food & Drug Administration's on-the-ground presence in China as an example of the emergence of cooperative agreements in global environmental governance. Part IV shows how increased rule …


Is Sugar The New Tobacco? How To Regulate Toxic Foods, Barbara L. Atwell Jan 2013

Is Sugar The New Tobacco? How To Regulate Toxic Foods, Barbara L. Atwell

Elisabeth Haub School of Law Faculty Publications

This article explores the health risks associated with added sugar. It then examines how, if at all, sugar should be regulated, by considering tobacco regulation as a possible model. Part I identifies the health risks of sugar consumption. Part II examines the reasons why sugar is added to so much of our food supply. Part III provides an overview of tobacco regulation, including educational initiatives, warning labels, advertising restrictions, age limitations, and taxes. Finally, Part IV provides a framework for sugar regulation, suggesting that most of the foregoing laws designed to discourage tobacco use should, with the exception of age …


From Peer-To-Peer Networks To Cloud Computing: How Technology Is Redefining Child Pornography Laws, Audrey Rogers Jan 2013

From Peer-To-Peer Networks To Cloud Computing: How Technology Is Redefining Child Pornography Laws, Audrey Rogers

Elisabeth Haub School of Law Faculty Publications

This Article traces the history of the child pornography laws and sentencing policy in Part I. Part II explains the technologies that have caused some of the current controversies, and then Part III describes how these technologies have blurred the offenses. Finally, Part IV makes suggestions as to how the law could better reflect technology and comport with a refined harm rationale. Courts, legal scholars, and medical experts have explained the harm includes the sexual abuse captured in the images and the psychological injury the victim endures knowing the images are being viewed. This Article further develops the harm rationale …


A "Blunt Withdrawal"? Bars On Citizen Suits For Toxic Site Cleanup, Margot J. Pollans Jan 2013

A "Blunt Withdrawal"? Bars On Citizen Suits For Toxic Site Cleanup, Margot J. Pollans

Elisabeth Haub School of Law Faculty Publications

Throughout the history of federal statutory environmental law, citizen suits have played a key role in enforcement. Through statutory interpretation, however, courts have narrowed the circumstances under which citizens can sue. This Article explores one such restraint: Courts have severely limited citizen suits under the Resource Conservation and Recovery Act (“RCRA”) by reading very broadly a jurisdiction-stripping provision of RCRA's companion statute, the Comprehensive Environmental Response Compensation and Liability Act (“CERCLA”). This Article argues that courts have read that provision too broadly, not only violating traditional principles for resolving inter-statutory conflict but also undermining the purposes of both statutes by …


Some Thoughts About The Historic Events That Led To The First Clinical Implantation Of A Total Artificial Heart, Denton A Cooley Jan 2013

Some Thoughts About The Historic Events That Led To The First Clinical Implantation Of A Total Artificial Heart, Denton A Cooley

The Texas Heart Institute Journal

No abstract provided.


Surgical Pulmonary Embolectomy: The Resurrection Of An Almost Discarded Operation, Samuel Z Goldhaber Jan 2013

Surgical Pulmonary Embolectomy: The Resurrection Of An Almost Discarded Operation, Samuel Z Goldhaber

The Texas Heart Institute Journal

No abstract provided.


Inverted Takotsubo Cardiomyopathy And The Fundamental Diagnostic Role Of Echocardiography, Arantza Manzanal, Lara Ruiz, Jose Madrazo, Majesh Makan, Julio Perez Jan 2013

Inverted Takotsubo Cardiomyopathy And The Fundamental Diagnostic Role Of Echocardiography, Arantza Manzanal, Lara Ruiz, Jose Madrazo, Majesh Makan, Julio Perez

The Texas Heart Institute Journal

Takotsubo cardiomyopathy is characterized by the development of transient focal wall-motion abnormalities that involve the apical and midventricular segments, in the absence of obstructive coronary artery disease. A variant, inverted takotsubo cardiomyopathy, was described in 2010. We report 3 cases in which each patient's transthoracic echocardiogram revealed the characteristic basal and midventricular segmental akinesis of this variant. This pattern is not associated with coronary artery distribution, and it therefore can be differentiated from coronary artery disease with the use of echocardiography, by evaluating the distribution and temporal changes of akinetic areas.


Components Of The Complete Blood Count As Risk Predictors For Coronary Heart Disease: In-Depth Review And Update, Mohammad Madjid, Omid Fatemi Jan 2013

Components Of The Complete Blood Count As Risk Predictors For Coronary Heart Disease: In-Depth Review And Update, Mohammad Madjid, Omid Fatemi

The Texas Heart Institute Journal

Atherosclerosis is an inflammatory disease, and several inflammatory biomarkers, such as C-reactive protein, have been used to predict the risk of coronary heart disease. High white blood cell count is a strong and independent predictor of coronary risk in patients of both sexes, with and without coronary heart disease. A high number of white blood cells and their subtypes (for example, neutrophils, monocytes, lymphocytes, and eosinophils) are associated with the presence of coronary heart disease, peripheral arterial disease, and stroke. The coronary heart disease risk ratios associated with a high white blood cell count are comparable to those of other …


Early Hemodynamic And Biochemical Changes In Overloaded Swine Ventricleearly Hemodynamic And Biochemical Changes In Overloaded Swine Ventricle, Sandro Gelsomino, Fabiana Lucà, Chiara Nediani, Sandra Zecchi Orlandini, Daniele Bani, Antonio S Rubino, Attilio Renzulli, Roberto Lorusso, Andrea Consolo, Antonino Lo Cascio, Jos Maessen, Gian Franco Gensini Jan 2013

Early Hemodynamic And Biochemical Changes In Overloaded Swine Ventricleearly Hemodynamic And Biochemical Changes In Overloaded Swine Ventricle, Sandro Gelsomino, Fabiana Lucà, Chiara Nediani, Sandra Zecchi Orlandini, Daniele Bani, Antonio S Rubino, Attilio Renzulli, Roberto Lorusso, Andrea Consolo, Antonino Lo Cascio, Jos Maessen, Gian Franco Gensini

The Texas Heart Institute Journal

The present study was undertaken to investigate, in an animal model, the relationship between sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) activity, phospholamban phosphorylation, acylphosphatase activity, and hemodynamic changes that occur in the early phase of pressure overload. In 54 study-group pigs, weighing 40±5 kg each, an aortic stenosis was created with a band of umbilical tape tied around the aorta; 18 sham-operated pigs formed our control group. Eight animals (6 study and 2 control) were randomly assigned to each experimental time (0.5, 3, 6, 12, 24, 48, 72, 96, and 168 hr). All indices of left ventricular function declined significantly, with a …


Osteosarcoma Tumor Thrombus: A Case Report With A Review Of The Literature, Pournima Navalkele, Sarah M Jones, Jason K Jones, Jorge D Salazar, Patrick C Toy, Rathi V Iyer, Betty Herrington Jan 2013

Osteosarcoma Tumor Thrombus: A Case Report With A Review Of The Literature, Pournima Navalkele, Sarah M Jones, Jason K Jones, Jorge D Salazar, Patrick C Toy, Rathi V Iyer, Betty Herrington

The Texas Heart Institute Journal

Tumor thrombus arising from osteosarcoma is rare. We report the case of a 20-year-old man with proximal humerus osteosarcoma, accompanied by an extensive intravascular tumor thrombus extending into the heart. Our review of the literature found 14 previous reports on osteosarcoma with tumor thrombus. The combination of positron emission tomography and computed tomography is very useful in differentiating tumor thrombus from vascular thrombus, thereby avoiding unnecessary anticoagulation therapy. This same imaging combination can also be used to evaluate the response to treatment. Surgical resection of the tumor thrombus is highly recommended. The effect of tumor thrombus on survival is still …


Mitochondrial Cardiomyopathy: Pathophysiology, Diagnosis, And Management, Deborah E Meyers, Haseeb Ilias Basha, Mary Kay Koenig Jan 2013

Mitochondrial Cardiomyopathy: Pathophysiology, Diagnosis, And Management, Deborah E Meyers, Haseeb Ilias Basha, Mary Kay Koenig

The Texas Heart Institute Journal

Mitochondrial disease is a heterogeneous group of multisystemic diseases that develop consequent to mutations in nuclear or mitochondrial DNA. The prevalence of inherited mitochondrial disease has been estimated to be greater than 1 in 5,000 births; however, the diagnosis and treatment of this disease are not taught in most adult-cardiology curricula. Because mitochondrial diseases often occur as a syndrome with resultant multiorgan dysfunction, they might not immediately appear to be specific to the cardiovascular system. Mitochondrial cardiomyopathy can be described as a myocardial condition characterized by abnormal heart-muscle structure, function, or both, secondary to genetic defects involving the mitochondrial respiratory …


Low Serum Triglyceride Levels As Predictors Of Cardiac Death In Heart Failure Patients, Guliz Kozdag, Gokhan Ertas, Ender Emre, Yasar Akay, Umut Celikyurt, Tayfun Sahin, Gozde Gorur, Kurtulus Karauzum, Irem Yilmaz, Dilek Ural, Mira Sarsekeyeva Jan 2013

Low Serum Triglyceride Levels As Predictors Of Cardiac Death In Heart Failure Patients, Guliz Kozdag, Gokhan Ertas, Ender Emre, Yasar Akay, Umut Celikyurt, Tayfun Sahin, Gozde Gorur, Kurtulus Karauzum, Irem Yilmaz, Dilek Ural, Mira Sarsekeyeva

The Texas Heart Institute Journal

Understanding the influence of sex differences on predictors of cardiac mortality rates in chronic heart failure might enable us to lengthen lifetimes and to improve lives. This study describes the influence of sex on cardiovascular mortality rates among chronic heart failure patients.

From January 2003 through December 2009, we evaluated 637 consecutive patients (409 men and 228 women) with chronic heart failure, who ranged in age from 18 through 94 years (mean age, 64 ± 13 yr) and ranged in New York Heart Association (NYHA) functional class from II through IV. The mean follow-up period was 38 ± 15 months, …


Two Cases Of Bezold-Jarisch Reflex Induced By Intra-Arterial Nitroglycerin In Critical Left Main Coronary Artery Stenosis, Sachin P Shah, Sergio Waxman Jan 2013

Two Cases Of Bezold-Jarisch Reflex Induced By Intra-Arterial Nitroglycerin In Critical Left Main Coronary Artery Stenosis, Sachin P Shah, Sergio Waxman

The Texas Heart Institute Journal

The Bezold-Jarisch reflex, a well-described phenomenon, occurs upon the stimulation of intracardiac mechanoreceptors and is mediated by vagal afferent nerve fibers. Several factors can sensitize the cardiovascular system to develop this reflex, including acute myocardial ischemia, natriuretic peptides, and, rarely, nitroglycerin administration in the setting of acute myocardial infarction. The development of the Bezold-Jarisch reflex in the presence of severe coronary artery stenosis, specifically left main coronary artery stenosis, has not been described. We report 2 cases of patients who underwent elective coronary angiography and were given intra-arterial nitroglycerin during radial sheath insertion to reduce radial artery spasm. In both …


Perventricular Device Closure Of Residual Muscular Ventricular Septal Defects After Repair Of Complex Congenital Heart Defects In Pediatric Patients, Da Zhu, Kaiyu Tao, Qi An, Shuhua Luo, Changping Gan, Ke Lin Jan 2013

Perventricular Device Closure Of Residual Muscular Ventricular Septal Defects After Repair Of Complex Congenital Heart Defects In Pediatric Patients, Da Zhu, Kaiyu Tao, Qi An, Shuhua Luo, Changping Gan, Ke Lin

The Texas Heart Institute Journal

Residual muscular ventricular septal defects are surgical challenges, especially after the repair of complex congenital heart defects. We investigated perventricular device closure as a salvage technique in pediatric patients who had postoperative residual muscular ventricular septal defects.

From February 2009 through June 2011, 14 pediatric patients at our hospital had residual muscular ventricular septal defects after undergoing surgical repair of complex congenital heart defects. Ten patients met our criteria for perventricular device closure of the residual defects: significant left-to-right shunting (Qp/Qs >1.5) or substantial hemodynamic instability (a defect ≥2 mm in size). The patients' mean age was 20.4 ± 13.5 …


Cor Triatriatum Sinister In A 43-Year-Old Man With Syncope, Janet L Eichholz, Samer S Hodroge, Jerry J Crook, John W Mack, Dale C Wortham Jan 2013

Cor Triatriatum Sinister In A 43-Year-Old Man With Syncope, Janet L Eichholz, Samer S Hodroge, Jerry J Crook, John W Mack, Dale C Wortham

The Texas Heart Institute Journal

Cor triatriatum sinister, a congenital cardiac anomaly involving a fibromuscular membrane that partitions the left atrium into 2 chambers, has been reported in only 0.1% to 0.4% of patients with congenital heart disease. The posterosuperior chamber receives blood from the pulmonary veins, and the anteroinferior chamber contains the left atrial appendage and mitral valve orifice. Most patients are diagnosed with the condition in infancy or childhood; adult cases are rare. We describe a case of cor triatriatum sinister in a 43-year-old man whose only presenting symptom was recurrent syncope. He underwent corrective resection of the membrane and was asymptomatic thereafter. …


Endovascular Treatment Of Acute Type B Dissection Complicating Aortic Coarctation, Seyed Ebrahim Kassaian, Kyomars Abbasi, Mehdi Mousavi, Mohammad Sahebjam Jan 2013

Endovascular Treatment Of Acute Type B Dissection Complicating Aortic Coarctation, Seyed Ebrahim Kassaian, Kyomars Abbasi, Mehdi Mousavi, Mohammad Sahebjam

The Texas Heart Institute Journal

Surgical treatment poses a high risk to patients with concomitant aortic coarctation and dissection, and an interventional approach could be an alternative. We describe the case of a 52-year-old man with a long history of untreated hypertension and aortic coarctation who emergently presented at our institution with an acute Stanford type B dissection. The patient's elevated serum creatinine level, perfusion deficit in the right lower limb, and hypertension did not respond to medical therapy, and he did not consent to surgery. By endovascular means, we used a self-expandable stent-graft to cover the entry point of the dissection; then, we deployed …


Coronary Artery Diameter Related To Calcium Scores And Coronary Risk Factors As Measured With Multidetector Computed Tomography: A Substudy Of The Accuracy Trial, Yasmin S Hamirani, Khurram Nasir, Emil Avanes, Jigar Kadakia, Matthew J Budoff Jan 2013

Coronary Artery Diameter Related To Calcium Scores And Coronary Risk Factors As Measured With Multidetector Computed Tomography: A Substudy Of The Accuracy Trial, Yasmin S Hamirani, Khurram Nasir, Emil Avanes, Jigar Kadakia, Matthew J Budoff

The Texas Heart Institute Journal

Arterial remodeling, an early change of atherosclerosis, can cause dilated arterial diameter. We measured coronary artery diameter with use of noncontrast 64-slice multidetector computed tomography (MDCT), and studied its association with coronary artery calcium levels and traditional coronary risk factors.

We included 140 patients from the ACCURACY trial whose noncontrast MDCT images showed measurable coronary arteries. Using 3 measurements of left main coronary artery (LMCA) and right coronary artery (RCA) diameters within 3 mm of the ostium, we associated the results with traditional coronary risk factors and calcium scores.

The prevalence of LMCA and RCA calcium was 22% and 51%, …


The Diagnosis Of Exclusion: An Ongoing Uncertainty, Herbert L Fred Jan 2013

The Diagnosis Of Exclusion: An Ongoing Uncertainty, Herbert L Fred

The Texas Heart Institute Journal

No abstract provided.


Stab Wound Of The Heart With Unusual Sequelae, Peter I Praeger, Jonathan Praeger, Ahmed M Abdel-Razek, Elie M Elmann Jan 2013

Stab Wound Of The Heart With Unusual Sequelae, Peter I Praeger, Jonathan Praeger, Ahmed M Abdel-Razek, Elie M Elmann

The Texas Heart Institute Journal

A 31-year-old woman was admitted to the emergency department with a stab wound to the heart. She was initially stable but rapidly developed hypotension. While the operating room and staff were in preparation, she underwent pericardiocentesis. She was then rushed to the operating room by the general surgical trauma team, who performed a bilateral anterior thoracotomy to control the bleeding. In the recovery room, the patient was still hypotensive, so cardiothoracic surgery was consulted.

An echocardiogram revealed severe hypokinesis of both ventricles. The cardiothoracic surgeons returned her to the operating room and discovered that the anterior pericardium had been completely …


Induction Of Early Biomarkers In A Thrombus-Induced Sheep Model Of Ischemic Heart Failure, Aluganti N Chandrakala, Pawel Kwiatkowski, Chittoor B Sai-Sudhakar, Benjamin Sun, Angela Phillips, Sampath Parthasarathy Jan 2013

Induction Of Early Biomarkers In A Thrombus-Induced Sheep Model Of Ischemic Heart Failure, Aluganti N Chandrakala, Pawel Kwiatkowski, Chittoor B Sai-Sudhakar, Benjamin Sun, Angela Phillips, Sampath Parthasarathy

The Texas Heart Institute Journal

The levels of brain natriuretic peptide (BNP) and monocyte chemoattractant protein-1 (MCP-1) are known to be increased in the sera of subjects with heart failure. Existing models do not account for the biomass of thrombus that occurs in patients undergoing myocardial infarction. In this study, we compared the expressions of sheep-derived genes for BNP, MCP-1, and atrial natriuretic peptide in a new large-animal model of thrombus-induced heart failure. Thrombus of autologous platelets was injected directly into the left circumflex coronary arteries of sheep. Cardiac ischemic injury was evaluated by troponin I levels, and heart failure progression was monitored with the …


Shifting Paradigms Transform Environmental And Land Use Law: The Emergence Of The Law Of Sustainable Development, John R. Nolon Jan 2013

Shifting Paradigms Transform Environmental And Land Use Law: The Emergence Of The Law Of Sustainable Development, John R. Nolon

Elisabeth Haub School of Law Faculty Publications

We began these two decades reacting to the market’s interest in developing greenfields and coastal property and end it wondering how to prepare more urbanized places for a growing population of smaller households who seek the amenities of urban living and some protection from the storms ahead. This essay discusses this and nine other fundamental paradigm shifts in environmental and economic conditions that are reshaping the law and changing the way state and local governments control land use and order human settlements.


The Economic Impact Of Metrohealth System, Matthew Hrubey, Ziona Austrian, Candi Clouse, Merissa Piazza Jan 2013

The Economic Impact Of Metrohealth System, Matthew Hrubey, Ziona Austrian, Candi Clouse, Merissa Piazza

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.


Central Georgia Regional Analysis: Demographics, Economy, Entrepreneurship And Innovation, Merissa Piazza, Joe Andre, Elorm M. Tsegah, Eunkyu Lee, Ziona Austrian Jan 2013

Central Georgia Regional Analysis: Demographics, Economy, Entrepreneurship And Innovation, Merissa Piazza, Joe Andre, Elorm M. Tsegah, Eunkyu Lee, Ziona Austrian

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.


How Many Antennas Does A Cooperative Jammer Need For Achieving The Degrees Of Freedom Of Multiple Antenna Gaussian Channels In The Presence Of An Eavesdropper?, Mohamed Nafea, Aylin Yener Jan 2013

How Many Antennas Does A Cooperative Jammer Need For Achieving The Degrees Of Freedom Of Multiple Antenna Gaussian Channels In The Presence Of An Eavesdropper?, Mohamed Nafea, Aylin Yener

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, multiple antenna Gaussian wiretap channels with a multiantenna cooperative jammer are considered. In particular, the focus is on identifying the spatial resources needed at the cooperative jammer in order to achieve a secure degree of freedom (s.d.o.f.) for the channel in question equal to the degrees of freedom (d.o.f.). In order to accomplish this goal, the cooperative jammer sets out to send correlated jamming signals. Simultaneously, the legitimate transmitter chooses a precoder that perfectly aligns its information signals over the jamming ones at the eavesdropper. Both terminals use structured signaling, i.e., discrete constellations. The proposed approach is …


A New Variable Step-Size Zero-Point Attracting Projection Algorithm, Jianming Liu, Steven L. Grant Jan 2013

A New Variable Step-Size Zero-Point Attracting Projection Algorithm, Jianming Liu, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a new variable step-size (VSS) scheme for the recently introduced zero-point attracting projection (ZAP) algorithm. The proposed variable step-size ZAPs are based on the gradient of the estimated filter coefficients' sparseness that is approximated by the difference between the sparseness measure of current filter coefficients and an averaged sparseness measure. Simulation results demonstrate that the proposed approach provides both faster convergence rate and better tracking ability than previous ones. © 2013 IEEE.


Low Complexity Soft-Interference Cancellation Turbo Equalization For Mimo Systems With Multilevel Modulations, Jingxian Wu, Longbao Wang, Chengshan Xiao Jan 2013

Low Complexity Soft-Interference Cancellation Turbo Equalization For Mimo Systems With Multilevel Modulations, Jingxian Wu, Longbao Wang, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a low complexity soft-interference cancellation equalizer (SICE) for the turbo detection of multiple-input multiple-output (MIMO) systems operating in time dispersive channels. The SICE contains three time-invariant linear filters: a feedforward filter, a causal feedback filter and an anti-causal feedback filter. The feedforward filter is designed to suppress the InterSymbol interference (ISI) due to time dispersive channels and the multiplexing interference from multiple transmit antennas. The causal (or anti-causal) feedback filter is developed to remove the residual interference caused by the symbols transmitted before (or after) the symbol under detection. The performance of the proposed SICE is verified …


Energy And Spectral Efficient Transmissions Of Coded Arq Systems, Jingxian Wu, Gang Wang, Yahong Rosa Zheng Jan 2013

Energy And Spectral Efficient Transmissions Of Coded Arq Systems, Jingxian Wu, Gang Wang, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

Energy efficiency (EE) and spectral efficiency (SE) feature one of the most fundamental tradeoffs in communication systems. In this paper, we propose an optimum transmission scheme for coded Type-I automatic repeat request (ARQ) systems to balance the EE-SE tradeoff. The optimization is performed with respect to a new design metric, the normalized EE (NEE), which is defined as the energy per bit normalized by the SE. Minimizing NEE means either reducing the energy per bit or increasing the SE, it thus yields a balanced tradeoff between the two. The system design incorporates a wide range of practical system parameters, such …


Neural Network-Based Adaptive Event-Triggered Control Of Affine Nonlinear Discrete Time Systems With Unknown Internal Dynamics, Avimanyu Sahoo, Hao Xu, S. Jagannathan Jan 2013

Neural Network-Based Adaptive Event-Triggered Control Of Affine Nonlinear Discrete Time Systems With Unknown Internal Dynamics, Avimanyu Sahoo, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the design of a neural network (NN) based adaptive model-based event-triggered control of an uncertain single input single output (SISO) nonlinear discrete time system in affine form is presented. The controller uses an adaptive estimator consisting of a single-layer NN not only to approximate the internal dynamics of an affine nonlinear discrete-time system but also to provide an estimate of the state vector during inter event interval. The NN weights of the adaptive NN estimator are tuned in a aperiodic manner at the event trigger instants unlike periodic updates in standard adaptive neural network (NN) control. A …


Neural Network-Based Optimal Control Of Mobile Robot Formations With Reduced Information Exchange, Travis Dierks, Bryan Brenner, S. Jagannathan Jan 2013

Neural Network-Based Optimal Control Of Mobile Robot Formations With Reduced Information Exchange, Travis Dierks, Bryan Brenner, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel formation control scheme for mobile robots is introduced in the context of leader-follower framework with reduced communication exchange. The dynamical controller inputs for the robots are approximated from nonlinear optimal control techniques in order to track the designed control velocities generated by the kinematic controller. The proposed nonlinear optimal control technique, referred to as adaptive dynamic programming, uses neural networks (NNs) to solve the optimal formation control problem in discrete time in the presence of unknown internal dynamics and a known control coefficient matrix. A modification to the follower's kinematic controller is used to allow the desired formation …


Harmonic Distortion Optimization Of Cascaded H-Bridge Inverters Considering Device Voltage Drops And Noninteger Dc Voltage Ratios, Bill Diong, Hossein Sepahvand, Keith Corzine Jan 2013

Harmonic Distortion Optimization Of Cascaded H-Bridge Inverters Considering Device Voltage Drops And Noninteger Dc Voltage Ratios, Bill Diong, Hossein Sepahvand, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

This paper considers achieving the minimum total harmonic distortion (THD) or frequency-weighted THD (WTHD) of the staircase-modulated output voltage of single-phase multilevel inverters, with or without elimination of the lowest order harmonics. The minimal THD values, together with the corresponding step angles and dc voltage source ratios, have been obtained for the 5-, 7-, 9-, 11-, and 13-level cases; accounting for the device voltage drops when the load is resistive or is moderately inductive is described. Similarly, the minimal WTHD values, together with the corresponding step angles and dc source voltage ratios, have been obtained for the five-, seven-, and …