Technology & Innovation 14(2) Abstracts

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Technology and Innovation, Vol. 14, pp. 81–91, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397570
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Thermal Energy Storage for Concentrating Solar Power Plants

Sarada Kuravi, Yogi Goswami, Elias K. Stefanakos, Manoj Ram, Chand Jotshi, Swetha Pendyala, Jamie Trahan, Prashanth Sridharan, Muhammad Rahman, and Burton Krakow

Clean Energy Research Center, University of South Florida, Tampa, FL, USA

Thermal energy storage for concentrating solar thermal power (CSP) plants can help in overcoming the intermittency of the solar resource and also reduce the levelized cost of energy (LCOE) by utilizing the power block for extended periods of time. In general, heat can be stored in the form of sensible heat, latent heat, and thermochemical reactions. This article describes the development of a cost-effective latent heat storage TES at the University of South Florida (USF). Latent heat storage systems have higher energy density compared to sensible heat storage systems. However, most phase change materials (PCMs) have low thermal conductivity that leads to slow charging and discharging rates. The effective thermal conductivity of PCMs can be improved by forming small macrocapsules of PCM and enhancing convective heat transfer by submerging them in a liquid. A novel encapsulation procedure for high-temperature PCMs that can be used for thermal energy storage (TES) systems in CSP plants is being developed at USF. When incorporated in a TES system, these PCMs can reduce the system costs to much lower rates than currently used systems. Economical encapsulation is achieved by using a novel electroless deposition technique. Preliminary results are presented and the factors that are being considered for process optimization are discussed.

Key words: High temperature thermal energy storage systems; Concentrating solar power plants; Novel encapsulation technologies; Economical encapsulation

Accepted April 3, 2012.
Address correspondence to Dr. Yogi Goswami, University of South Florida, 4202 E. Fowler Ave., ENB 118, Tampa, FL 33620, USA. Tel: 1-813-974-7322; Fax: 1-813-974-2050; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 93–101, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397615
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Hydrokinetic Energy in the Sunshine State: Challenges of Florida’s Unique Renewable Resource

Howard P. Hanson

Southeast National Marine Renewable Energy Center, Florida Atlantic University, Boca Raton, FL, USA

With more shoreline than any state except Alaska, Florida’s offshore environment plays significant roles in the state’s economy through its contributions to tourism, shipping, and both commercial and recreational fishing. As society transitions away from reliance on fossil fuels in the future, Florida’s oceans also have the potential to play yet another role for the state as a source of clean, renewable energy. Because marine renewable energy, both in Florida and elsewhere, is a relatively new sector, its technology is considerably less mature than other renewable technologies, and its challenges present significant opportunities for innovation. Capturing the kinetic energy of the Florida Current will require both materials advances and new designs for marine current turbines and their efficient deployment. This article reviews Florida’s hydrokinetic marine renewable energy resource and the prospects for implementing technology to recover power on commercial scales.

Key words: Marine renewable energy; Marine and hydrokinetic energy; Florida Current; Marine current turbine

Accepted April 4, 2012.
Address correspondence to Dr. Howard P. Hanson, Southeast National Marine Renewable Energy Center, Florida Atlantic University, 777 Glades Road/EE96-315, Boca Raton, FL 33431, USA. Tel: 561-297-2560; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 103–113, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397651
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Nanoscale Rectenna for Thermal Energy Conversion to Electricity

S. Krishnan, Y. Goswami, and E. Stefanakos

Clean Energy Research Center, College of Engineering, University of South Florida, Tampa, FL, USA

This article presents a quantum approach to increasing the efficiency of solar/thermal energy conversion by converting waste heat to electrical energy using a rectenna (a combination of high-frequency antenna and tunnel diode). The approach of using a rectenna in combination with a plasmonic blackbody emitter would improve efficiency of all systems. This research will significantly increase the efficiency of photovoltaic (PV) cells at little added cost by integrating the plasmonic emitter with the cell. This development will also accelerate the development of the infrared (IR) rectenna, which can convert thermal radiation to electricity at potentially much higher efficiencies than conventional PV. Manufacturing an inexpensive and reliable energy conversion device will have significant implications on several commercial and governmental applications meeting national needs such as ever-increasing energy demands through the use of simple and cost-effective methodologies. This article presents the current state of the art in the field of rectenna-based conversion with a focus on its critical components.

Key words: Rectenna; Emitter; MIM diode; Energy conversion

Accepted April 5, 2012.
Address correspondence to S. Krishnan, Clean Energy Research Center, College of Engineering, University of South Florida, 4202 E. Fowler Ave., Tampa, FL 33620, USA. Tel: (813)-974-8840; Fax: (813)-974-5250; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it or Y. Goswami, College of Engineering, University of South Florida, 4202 E. Fowler Ave., Tampa, FL 33620, USA. Tel: (813)-974-8840; Fax: (813)-974-5250; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 115–130, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397697
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Challenges and Consequences of Carbon Dioxide as an Oxidizing Agent for Hydrogen Generation From Hydrocarbons

Selma Hokenek,* Devin Walker,* Yolanda A. Daza,* Erum Qayyum,* Matthew M. Yung,† John T. Wolan,* and John N. Kuhn*

*Department of Chemical & Biomedical Engineering, University of South Florida, Tampa, FL, USA
†National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, USA

Hydrogen generation is important to a number of key current and future energy technologies including hydrotreating, ammonia synthesis, and fuel cells. Although methane-steam reforming is an industrial practice, there is a growing interest to use carbon dioxide as the oxidizing or co-oxidizing agent in an effort to enhance the use of carbon dioxide. The purpose of this contribution is to describe and assess technological advances in the area of hydrogen generation from natural gas and biomass with a focus on carbon dioxide as an oxidizing agent.

Key words: Hydrogen (H2); Energy; Carbon dioxide (CO2); Biomass-to-fuels

Accepted April 9, 2012.
Address correspondence to John N. Kuhn, Department of Chemical & Biomedical Engineering, University of South Florida, 4202 East Fowler Avenue, ENB 118, Tampa, FL 33620, USA. Tel: (813) 974-6498; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 131–141, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397732
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

FAMU Spheromak and the Turbulent Physics Experiment—STPX

James B. Titus,* Alonzo B. Alexander,* Kyron Williams,* Charles Weatherford,* and Joseph A. Johnson III†

*Florida A&M University, Tallahassee, FL, USA
†Pyrmid Plasmas, LLC, Lawrenceville, GA, USA

Fusion research is a key element in the nation’s long-term energy supply strategy. Florida A&M University’s Center for Plasma Science and Technology (FAMU CePaST) is building a spheromak fusion device, where fusion energy research is on the forefront of clean energy technology. The Spheromak Turbulent Physics Experiment (STPX) is in a class of experiments used to investigate the physics principles of self-organized plasmas. This is relevant for the development of an economically feasible, controlled fusion reactor as a source of electrical power. The project involves collaboration between FAMU CePaST, West Virginia University, and Auburn University. This project will determine, using theory, experiment, and simulation, the essential elements required for full kinetic modeling of an entire spheromak plasma using ab initio magnetohydrodynamic (MHD) with direct modifications from new turbulence physics. High time resolution measurements of electron temperatures, ion temperatures, and magnetic field fluctuations will be used to study turbulence during magnetic reconnection, anomalous ion heating, dusty plasmas, and equilibrium modification. This article assesses the clean energy technology of the spheromak device, the plasma regimes that a spheromak will provide, and discusses its role in understanding turbulence, an essential part of fusion.

Key words: Fusion; Plasmas; Spheromak; Clean energy; Turbulence

Accepted April 9, 2012.
Address correspondence to James B. Titus, 2077 E. Paul Dirac Dr., Tallahassee, FL 32310, USA. Tel: 850-599-3943; Fax: 850-599-3901; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 143–151, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397778
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Conjunctive Injection of CO2 and Wastewater in a Heterogeneous Porous Formation

Roland T. Okwen,* Mark Thomas,* Mark T. Stewart,† Maya Trotz,* and Jeffrey A. Cunningham*

*Department of Civil and Environmental Engineering, University of South Florida, Tampa, FL, USA
†Department of Geology, University of South Florida, Tampa, FL, USA

One of the major obstacles to development, implementation, and deployment of carbon capture and storage (CCS) is cost. As a result, sustainably combining CCS with existing technologies to make CCS less costly or even profitable is vital. This article proposes a CCS strategy in which captured anthropogenic carbon dioxide (CO2) and treated municipal wastewater are simultaneously injected into a confined saline aquifer. Numerical simulations of conjunctive injection of CO2 and wastewater into a confined saline aquifer were conducted under heterogeneous conditions. Simulation results were evaluated based on spatial distributions of gas saturation, and pressure, over an injection period of 10 years. Results from the simulation of CO2-wastewater injection (3214 tons/day) into a carbonate saline aquifer predict very low gas saturations and enhancement of dissolved CO2 mass fraction as a result of the dissolution of CO2 into wastewater and native brine. Vertical baffling of the CO2 plume was achieved due to vertical heterogeneity of the injection zone thereby reducing reliance on caprock integrity in ensuring CO2 storage security. Comparison of simulation results of conjunctive CO2-wastewater injection to those of single phase CO2 and wastewater injection suggest that coinjection of CO2 and wastewater in deep confined saline aquifers enhances CO2 storage efficiency and security.

Key words: Carbon dioxide; Municipal wastewater; Vertical baffling; Buoyancy

Accepted April 10, 2012.
Address correspondence to Roland T. Okwen at his current address: Illinois State Geological Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, 615 East Peabody Drive, MC-650, Champaign, IL 61820, USA. Tel: +1-(217)-244-2869; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 153–165, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397813
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Low-Frequency Ripples and Resonances in Wind and Solar Grid Integration Systems: An Overview

Zhixin Miao

Department of Electrical Engineering, University of South Florida, Tampa, FL, USA

This article examines low-frequency ripples and resonances presented in wind and solar systems. Power electronic interface topologies for solar energy system, Type 3 and Type 4 wind generators are presented. For typical converters, control objectives and control schemes are also presented. Three types of ripples and resonances are examined and they are: the 120 Hz ripple presented in DC systems due to single-phase operation or three-phase unbalanced operation, resonances with frequencies larger than 60 Hz due to converter and grid inductance interaction, resonances with frequencies less than 60 Hz or subsynchronous resonances (SSR) due to interactions between wind generators and series compensated networks. Causes and mitigation schemes for the three types of ripples and resonances are also reviewed.

Key words: Wind; Solar; Power electronic converters; Ripples; Resonances

Accepted April 16, 2012.
Address correspondence to Zhixin Miao, Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Ave. ENB 118, Tampa, FL 33620, USA. Tel: 813-699-9188; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 167–178, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397859
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Droop Control in Voltage Source Converters for Microgrid Operation With Pulsed Power Loads

Lakshan P. Piyasinghe and Zhixin Miao

Department of Electrical Engineering, University of South Florida, Tampa, FL, USA

This article investigates the microgrid operation and control with pulsed power loads (PPLs). Due to the highly intermittent nature of pulsed power loads, they have a major impact on the stability of the power system. Since power electronic converters such as back-to-back converters and inverters are often engaged to connect renewable energy sources to the microgrid, this article studies how to utilize these converters to compensate the impact caused by PPLs. Two control strategies, centralized control and decentralized control, are proposed and compared to minimize the system impact caused by pulsed power loads. Voltage and frequency droop controls are employed for the decentralized control. A study system is built in PSCAD/EMTDC and the proposed control architectures are implemented. Simulation results demonstrate the effectiveness of droop control in operation enhancement in microgrids with PPLs.

Key words: Inverter; Microgrid; Pulsed power loads (PPLs); Voltage source converter

Address correspondence to Zhixin Miao, Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Ave. ENB 118, Tampa, FL 33620, USA. Tel: 813-974-4237; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 181–183, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397930
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Commentary: Patents for Humanity: Connecting Innovation With Humanitarian Endeavor

Alex Camarota,* Elizabeth Dougherty,* and Edward Elliott†

*Office of Innovation Development, United States Patent and Trademark Office, Alexandria, VA, USA
†Office of Policy and External Affairs, United States Patent and Trademark Office, Alexandria, VA, USA

Patents for Humanity, a prize competition sponsored by the United States Patent and Trademark Office (USPTO), recognizes individuals and companies that have used patented technology for humanitarian purposes throughout the world. Applicants compete in four categories: medicine and medical diagnostic technology, food and nutrition technology, clean technology, and information technology. Winners will receive publicity and recognition in a ceremony at the USPTO. Additionally, they will receive a certificate for accelerated processing of a matter before the USPTO. Deadline for applicants is October 31, 2012.

Key words: Patents for Humanity; Innovation; Humanitarian technology; Competition; United States Patent and Trademark Office (USPTO)

Accepted May 1, 2012.
Address correspondence to Elizabeth Dougherty, Office of Innovation Development, U.S. Patent and Trademark Office, 600 Dulany Street, Alexandria, VA 22314, USA. E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 185–197, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021397976
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Asset Mapping of a Major Research University Using Innovation Hub Modeling

Eve Spengler,*† Johnmark White,*‡ Mohamad Kasti,‡ and Michael W. Fountain*§¶#

*USF Center for Entrepreneurship, University of South Florida, Tampa, FL, USA
†Alliance for Integrated Spatial Technologies, University of South Florida, Tampa, FL, USA
‡USF Center for Transformation and Innovation, University of South Florida, Tampa, FL, USA
§Department of Marketing, College of Business, University of South Florida, Tampa, FL, USA
¶Department of Industrial and Management Systems Engineering, College of Engineering, University of South Florida, Tampa, FL, USA
#Department of Psychiatry and Behavioral Medicine, College of Medicine, University of South Florida, Tampa, FL, USA

This article serves as an examination of the current resources available to assist innovation at the University of South Florida as viewed through Asset Mapping. It evaluates the organizational framework of the university to support the process of innovation. This study was conducted using a novel design developed by the authors for innovation hub modeling. The strengths, weaknesses, and gaps of the university environment to support the various lifecycle phases of technology transfer and commercialization are identified. This study provides insight into the infrastructure of universities to support research and commercialization, and may be utilized by other colleges and universities to evaluate their innovation capabilities.

Key words: Innovation; Asset map; Innovation life cycle; Innovation hub; Technology transfer; Technology management; Research; Product commercialization

Accepted March 9, 2012.
Address correspondence to Michael W. Fountain, University of South Florida, 4202 East Fowler Avenue, BSN 3403, Tampa, FL 33620, USA. Tel: (813)974-7900; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it orEve Spengler, University of South Florida, 4202 East Fowler Avenue, BSN 3403, Tampa, Florida 33620, USA. Tel: (813)974-7900; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 199–208, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021398010
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Use of Fused Circulations to Investigate the Role of Apolipoprotein E as Amyloid Catalyst and Peripheral Sink in Alzheimer’s Disease

Lars N. G. Nilsson,*† Sylvia Gografe,‡ David A. Costa,* Tiffany Hughes,* David Dressler,§ and Huntington Potter*¶

*Department of Molecular Medicine and Suncoast Gerontology Center, University of South Florida, Tampa, FL, USA
†Department of Pharmacology, Faculty of Medicine, University of Oslo and Oslo University Hospital, Oslo, Norway
‡Comparative Medicine, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
§Balliol College and Oxford University, Oxford, UK
¶USF Byrd Alzheimer’s Institute, Tampa, FL, USA

Apolipoprotein E (apoE) synthesized in liver and brain plays a key role in both cholesterol transport and Alzheimer’s disease (AD): apoE-knockout mice develop hypercholesterolemia and atherosclerosis and cannot support AD amyloid deposition. The ApoE4 allele is the strongest genetic risk factor for late-onset AD, and apoE4 protein preferentially catalyzes amyloid-beta (Aβ) peptide fibrillization in vitro and amyloid plaque deposition in vivo. Circulating apoE may also have the potential to draw Aβ from the brain and reduce amyloid deposition. We used parabiosis to determine how circulating apoE impacts brain amyloid deposition and blood cholesterol levels in transgenic mice carrying AD-promoting APP and PS1 human transgenes—either with or without the endogenous mouse apoE gene. ApoE transferred through the joined circulations from WT to parabiosed APP+/+,PS1+/−,apoE-KO mice prevented hypercholesterolemia and reduced already low brain amyloid deposition. The findings indicate that apoE synthesis in the brain itself is necessary for amyloid accumulation. Furthermore, plasma apoE can both normalize cholesterol levels in apoE-KO mice and act as a peripheral sink to induce net efflux of Aβ peptide from the brain. The therapeutic implication is that inhibiting Alzheimer’s disease neuropathology may be accomplished by either reducing apoE in the brain or increasing apoE in the blood.

Key words: Apolipoprotein E (apoE); Parabiosis; Amyloid; Alzheimer’s disease; Atherosclerosis; Blood

Accepted March 22, 2012.
Address correspondence to Prof. Huntington Potter at his current address: Alzheimer’s Disease Program, Department of Neurology and Linda Crnic Institute for Down Syndrome, University of Colorado School of Medicine, Mail Stop 8608, Research Complex 2 P15-4009, 12700 East 19th Ave., Aurora, CO 80045, USA. Tel: (303) 724-7385; Fax: (303)724-5741; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it


Technology and Innovation, Vol. 14, pp. 209–217, 2012
1929-8241/12 $90.00 + .00
DOI: http://dx.doi.org/10.3727/194982412X13462021398056
E-ISSN 1949-825X
Copyright ©2012 Cognizant Comm. Corp.
Printed in the USA. All rights reserved

Nanotechnology Solutions to Greenhouse and Urban Agriculture

Sarath Witanachchi,* Marek Merlak,* and Prasanna Mahawela†

*Department of Physics, University of South Florida, Tampa, FL, USA
†EngenNano Technology, Tampa Bay Technology Incubator, Tampa, FL, USA

Conventional farming techniques used today involve irrigation of soil with large amounts of water and fertilizer, spraying of pesticides, and churning of the soil that releases large amounts of greenhouse gasses such as methane. In addition, farmers are at the mercy of weather conditions, droughts, and floods that may cause extensive damage to their crops. Increasingly greenhouse farming and urban agriculture are being looked at as more efficient and cost-effective way to grow produce. Both in greenhouse and urbane agriculture artificial lighting for photosynthesis is an essential component. Only light at wavelengths around 460 nm (blue) and 670 nm (red) are absorbed by most of the plants for photosynthesis. Currently used discharge lamps in greenhouses distribute energy in the entire visible region, yet plants absorb only 30% of the light. Solid-state lighting sources that cater to the exact wavelengths required by plants that are synchronized with the local CO2 concentration will be the most efficient grow light for agriculture. This article presents a nanophosphor-based light source that is being developed as an efficient grow light for agriculture, which has the potential to produce significant savings in energy costs.

Key words: Electroluminescence; Nanophosphor; Grow-light; Green house/urbane agriculture

Accepted March 14, 2012.
Address correspondence to Sarath Witanachchi, Department of Physics, University of South Florida, ISA 2019, Tampa, FL 33620, USA. Tel: 813-974-2789; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it