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2011

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Full-Text Articles in Engineering

Acuta Enews September 2011, Vol 40, No. 9 Sep 2011

Acuta Enews September 2011, Vol 40, No. 9

ACUTA Newsletters

ln This lssue

Hurricane lrene Takes Top Priority for Some

From the President: ACUTA: A Career Development Program Joe Harrington, Boston College

To Attract Top lT Talent, Understand Graduates' Needs

You Don't Have to Be Young to Be "Young"............. Emily Harris, Vassar College

Add Names from Your Campus to Your ACUTA Roster

Freed-Hardeman Students Develop iPhone App

Announcing member Benefit of the Month

lnfo Links ..........Randy Hayes, Univ. of Northern lowa

Retirement

Committee Corner

ACUTA Fall Seminar in Boston

ACUTA Webinar: Transitioning to lPv6 on Your Campus

Board Report..................Riny Ledgerwood, San Diego state univ

Welcome New Members

Check lt Out: …


Breakdown Voltage Of Ultrathin Dielectric Film Subject To Electrostatic Discharge Stress, Hao Jin, Shurong Dong, Meng Miao, Juin Jei Liou, Cary Y. Yang Sep 2011

Breakdown Voltage Of Ultrathin Dielectric Film Subject To Electrostatic Discharge Stress, Hao Jin, Shurong Dong, Meng Miao, Juin Jei Liou, Cary Y. Yang

Electrical and Computer Engineering

Ultrathin silicon oxide film for nano-electromechanical system (NEMS) applications is investigated under electrostatic discharge (ESD) stress using a transmission line pulse (TLP) tester. The measured breakdown voltage and transient response are analyzed. The results show that the voltage stress time has a significant effect on the breakdown voltage. By shortening the stress time, the breakdown voltage increases by 2–3 times. With the area shrinking breakdown voltage increases, and there is a critical value, below which the breakdown voltage increases dramatically with decreasing area. It is possible to enhance the ESD robustness by using a multiple small-area dielectric layer structure. Shorten …


A Quantitative Study Of The Weldability Of Inconel 718 Using Gleeble And Varestraint Test Methods, Sean Quigley Sep 2011

A Quantitative Study Of The Weldability Of Inconel 718 Using Gleeble And Varestraint Test Methods, Sean Quigley

Master's Theses

Nickel super alloy Inconel 718 was tested and compared to Haynes 230 using Gleeble and Varestraint mechanical test methods. Hot cracking susceptibility was examined in either alloy using a sub-scale Varestraint test method at 5 augmented strain levels: 0.25%, 05.%, 1%, 2%, and 4%. Maximum crack length, total crack length, and number of cracks were measured for each strain level. Gleeble hot ductility on-heating and on-cooling tests were performed on both alloys. Inconel 718 was tested on-heating at target temperatures of 1600˚F, 2000˚F, 2100˚F, 2200˚F, and on cooling at 1600˚F, 1700˚F, 1800˚F, 1900˚F, and 2100˚F. Haynes 230 was tested on-heating …


No-Free-Lunch Result For Interval And Fuzzy Computing: When Bounds Are Unusually Good, Their Computation Is Unusually Slow, Ildar Batyrshin, Martine Ceberio, Vladik Kreinovich Sep 2011

Extreme Distributions On Intervals, Monchaya Chiangpradit, Wararit Panichkitkosolkul, Hung T. Nguyen, Vladik Kreinovich Sep 2011

Mission Performance Considered As Point Performance In Aircraft Design, Robert A. Mcdonald Sep 2011

Mission Performance Considered As Point Performance In Aircraft Design, Robert A. Mcdonald

Aerospace Engineering

The cruise or loiter performance of an aircraft is intimately tied to its wing loading and its thrust-to-weight ratio. Paradoxically, mission performance is often not considered when these fundamental aircraft parameters are determined in conceptual design. In this paper, the traditional constraint diagram is extended to include contours of range or endurance parameter. These performance metrics represent the mission-performance capability of the aircraft without sizing the aircraft to a particular mission. This gives the designer an immediate and intuitive understanding of the tradeoff between the point and mission performance of the aircraft. The potential freedom for the designer to choose …


Impact Isolation Of Training Shoes, Nicci Daly, Stephen Tiernan Sep 2011

Impact Isolation Of Training Shoes, Nicci Daly, Stephen Tiernan

Conference Papers

ABSTRACT The increase in popularity of physical activities from fun runs to competitive marathons has lead to a huge industry in sports footwear, which is now worth $20bn annually. There is a resultant increase in injuries, largely due to the repeated and prolonged nature of the impact forces experienced by the leg. Clinical data indicates that the knee is the most common site of running related injury, followed by the lower leg and foot. The complexity of the ankle structure means that injuries are acute and the success rates of replacements are very low. Therefore research in this area is …


Quality Of Traffic Flow On Urban Arterial Streets And Its Relationship With Safety, Vinayak V. Dixit, Anurag Pande, Mohamed Abdel-Aty, Abhishek Das, Essam Radwan Sep 2011

Quality Of Traffic Flow On Urban Arterial Streets And Its Relationship With Safety, Vinayak V. Dixit, Anurag Pande, Mohamed Abdel-Aty, Abhishek Das, Essam Radwan

Civil and Environmental Engineering

The two-fluid model for vehicular traffic flow explains the traffic on arterials as a mix of stopped and running vehicles. It describes the relationship between the vehicles’ running speed and the fraction of running vehicles. The two parameters of the model essentially represent ‘free flow’ travel time and level of interaction among vehicles, and may be used to evaluate urban roadway networks and urban corridors with partially limited access. These parameters are influenced by not only the roadway characteristics but also by behavioral aspects of driver population, e.g., aggressiveness. Two-fluid models are estimated for eight arterial corridors in Orlando, FL …


Application Of Noise Cancelling And Damage Detection Algorithms In Nde Of Concrete Bridge Decks Using Impact Signals, Gang Zhang, Ronald S. Harichandran, Pradeep Ramahulli Sep 2011

Application Of Noise Cancelling And Damage Detection Algorithms In Nde Of Concrete Bridge Decks Using Impact Signals, Gang Zhang, Ronald S. Harichandran, Pradeep Ramahulli

Civil Engineering Faculty Publications

Delamination is a commonly observed distress in concrete bridge decks. Among all the delamination detection methods, acoustic methods have the advantages of being fast and inexpensive. In traditional acoustic inspection methods, the inspector drags a chain alone or hammers on the bridge deck and detects delamination from the “hollowness” of the sound. The signals are often contaminated by ambient traffic noise and the detection of delamination is highly subjective. This paper describes the performance of an impact-based acoustic NDE method where the traffic noise was filtered by employing a noise cancelling algorithm and where subjectivity was eliminated by introducing feature …


In The Path Of An F3 Tornado, Bob David Sep 2011

In The Path Of An F3 Tornado, Bob David

Goderich August 21 2011 F3 Tornado Associated Files

the Port of Goderich Approximate path of the tornado, August 21, 2011 4:00 p.m. Direction of travel NW to SE for a distance of about 20 km.

Winds reached up to 300 km per hour. The width of the path averaged about 500 metres.


The Comparison Of Gev, Log-Pearson Type 3 And Gumbel Distributions In The Upper Thames River Watershed Under Global Climate Models, Nick Millington, Samiran Das, Slobodan P. Simonovic Sep 2011

The Comparison Of Gev, Log-Pearson Type 3 And Gumbel Distributions In The Upper Thames River Watershed Under Global Climate Models, Nick Millington, Samiran Das, Slobodan P. Simonovic

Water Resources Research Report

The increase in greenhouse gas emissions has had a severe impact on global temperature, and is affecting weather patterns worldwide. With this global climate change, precipitation levels are changing, and in many places are drastically increasing. The need to be able to accurately predict extreme precipitation events is imperative in designing for not only the safety of infrastructure, but also people’s lives. To predict these events, the use of historical data is necessary, along with statistical distributions that are used to fit the data.

In this study, historical data from the London International Airport station has been used, along with …


A Novel High Sensitive Optical Fiber Microphone Based On A Singlemode-Multimode-Singlemode Structure, An Sun, Yuliya Semenova, Qiang Wu, Agus Hatta, Gerald Farrell Sep 2011

A Novel High Sensitive Optical Fiber Microphone Based On A Singlemode-Multimode-Singlemode Structure, An Sun, Yuliya Semenova, Qiang Wu, Agus Hatta, Gerald Farrell

Articles

In this paper, a novel multimode interference based optical fiber microphone by employing singlemode-multimode-singlemode (SMS) structure is presented. The acoustic vibration is measured by detecting the transmission loss of the SMS structure that attached to a thick aluminum membrane. Experiments are carried on to test the performance of SMS structured fiber microphone and the experimental results show that the SMS fiber sensor can effectively detect the acoustic signal within the audio range of 20 KHz. It also exhibits a high sensitivity and human voice can also be picked up effectively within the distance of 2 m.


Designing Propulsion Systems For Future Aerospace Applications, Nihad E. Daidzic Sep 2011

Designing Propulsion Systems For Future Aerospace Applications, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


Bioenergy Feedstock-Specific Enrichment Of Microbial Populations During High-Solids Thermophilic Deconstruction, Amitha P. Reddy, Martin Allgaier, Steven W. Singer, Terry C. Hazen, Blake A. Simmons, Philip Hugenholtz, Jean S. Vandergheynst Sep 2011

Bioenergy Feedstock-Specific Enrichment Of Microbial Populations During High-Solids Thermophilic Deconstruction, Amitha P. Reddy, Martin Allgaier, Steven W. Singer, Terry C. Hazen, Blake A. Simmons, Philip Hugenholtz, Jean S. Vandergheynst

United States Department of Energy: Publications

Thermophilic microbial communities that are active in a high-solids environment offer great potential for the discovery of industrially relevant enzymes that efficiently deconstruct bioenergy feedstocks. In this study, finished green waste compost was used as an inoculum source to enrich microbial communities and associated enzymes that hydrolyze cellulose and hemicellulose during thermophilic high-solids fermentation of the bioenergy feedstocks switchgrass and corn stover. Methods involving the disruption of enzyme and plant cell wall polysaccharide interactions were developed to recover xylanase and endoglucanase activity from deconstructed solids. Xylanase and endoglucanase activity increased by more than a factor of 5, upon four successive …


Performance Analysis Of Cognitive Radio Systems Under Qos Constraints And Channel Uncertainty, Sami Akin, Mustafa Cenk Gursoy Sep 2011

Performance Analysis Of Cognitive Radio Systems Under Qos Constraints And Channel Uncertainty, Sami Akin, Mustafa Cenk Gursoy

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, performance of cognitive transmission over time-selective flat fading channels is studied under quality of service (QoS) constraints and channel uncertainty. Cognitive secondary users (SUs) are assumed to initially perform channel sensing to detect the activities of the primary users, and then attempt to estimate the channel fading coefficients through training. Energy detection is employed for channel sensing, and different minimum mean-square-error (MMSE) estimation methods are considered for channel estimation. In both channel sensing and estimation, erroneous decisions can be made, and hence, channel uncertainty is not completely eliminated. In this setting, performance is studied and interactions between …


Mimo Wireless Communications Under Statistical Queueing Constraints, M. Cenk Gursoy Sep 2011

Mimo Wireless Communications Under Statistical Queueing Constraints, M. Cenk Gursoy

Department of Electrical and Computer Engineering: Faculty Publications

The performance of multiple-input multiple-output (MIMO) wireless systems is investigated in the presence of statistical queueing constraints. Queuing constraints are imposed as limitations on buffer violation probabilities. The performance under such constraints is captured through the effective capacity formulation. A detailed analysis of the effective capacity is carried out in the low-power, wideband, and high signal-to-noise ratio (SNR) regimes. In the low-power analysis, expressions for the first and second derivatives of the effective capacity with respect to SNR at SNR = 0 are obtained under various assumptions on the degree of channel state information at the transmitter. Transmission strategies that …


A Heuristic For Selecting The Cycle Length For Fairio, Sarala Arunagiri, Y. Kwok, Patricia J. Teller, R. A. Portillo, S. Seelam Sep 2011

Numerical Modeling Of Steady Burning Characteristics Of Spherical Ethanol Particles In A Spray Environment, Vaibhav Kumar Sahu, Vasudevan Raghavan, Daniel N. Pope, George Gogos Sep 2011

Numerical Modeling Of Steady Burning Characteristics Of Spherical Ethanol Particles In A Spray Environment, Vaibhav Kumar Sahu, Vasudevan Raghavan, Daniel N. Pope, George Gogos

Department of Mechanical and Materials Engineering: Faculty Publications

A numerical study of steady burning of spherical ethanol particles in a spray environment is presented. A spray environment is modeled as a high temperature oxidizer stream where the major products of combustion such as carbon dioxide and water vapor will be present along with reduced amounts of oxygen and nitrogen. The numerical model, which employs variable thermophysical properties, a global single-step reaction mechanism, and an optically thin radiation model, has been first validated against published experimental results for quasi-steady combustion of spherical ethanol particles. The validated model has been employed to predict the burning behavior of the ethanol particle …


Review Of "Handbook For Blast Resistent Design Of Buildings", Norbert J. Delatte Sep 2011

Review Of "Handbook For Blast Resistent Design Of Buildings", Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

No abstract provided.


Successful Engineering And Technology Student Mobility: Key Student Perspectives And Quality Determinants Before, During And After Student Exchange Under The Atlantis Programme, Mike Murphy, Donal Mchale, Michael Dyrenfurth Sep 2011

Successful Engineering And Technology Student Mobility: Key Student Perspectives And Quality Determinants Before, During And After Student Exchange Under The Atlantis Programme, Mike Murphy, Donal Mchale, Michael Dyrenfurth

Conference papers

In this paper, we describe the lessons learned, and determinants of quality, from two Atlantis programmes. Additionally our two student authors will share key student perspectives relevant to student mobility: (1) before they visited the partner university, (2) while they were studying at the partner university and (3) after they returned to their home university. Purdue University and the Technological University Dublin, together with the Hochschule Darmstadt and Pennsylvania State University, were successful in securing an Atlantis mobility grant [1] for four years to support student and staff mobility between the United States and Europe. The programme has just completed …


The Effects Of Interface Protection Requirements On The Stability Of Embedded Generation Connected To The Irish Distribution System, Damien Glennon Sep 2011

The Effects Of Interface Protection Requirements On The Stability Of Embedded Generation Connected To The Irish Distribution System, Damien Glennon

Msc. in Energy Management

The electricity sector in Ireland has undergone a number of changes in the last 20 years. In the early 90’s the fuel mix was predominantly fossil fuel based with a very small percentage of renewables on the system. The electricity generation portfolio was dominated by coal/gas/peat fired power stations which used large synchronous machines to generate electricity. These synchronous machines provided the necessary system inertia and kept the system frequency stable. However, rising fuel costs, dwindling fossil fuel supplies, climate change etc. has driven the growth of renewable energy especially in the electricity sector. Current targets for renewable energy in …


Lotus Effect Toy, Said Shakerin Sep 2011

Lotus Effect Toy, Said Shakerin

All Faculty Articles - School of Engineering and Computer Science

This is a short article about Aqua Drop, a toy that employs a superhydrophobic surface. After defining superhydrophobic surface, its occurrence in nature, and its importance in science and technology, I describe the toy, followed by several student activities that can be performed with the toy and easily found natural objects.


A Review Of Parallel Operation Of Active Power Filters In The Distributed Generation System, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon Sep 2011

A Review Of Parallel Operation Of Active Power Filters In The Distributed Generation System, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon

Conference papers

In this paper a technical review of parallel operation of Active Power Filter (APF) for harmonic power compensation in distributed generation (DG) network has been presented. Controlling methods and connection topologies with their pros and cons are described. Recent improvements in controlling and future trends for the application of APFs in distributed mode are also identified.


Observations Of The Wind Resource Across The Dublin Urban Area, Keith Sunderland, Michael Conlon, Gerald Mills, Rowan Feely Sep 2011

Observations Of The Wind Resource Across The Dublin Urban Area, Keith Sunderland, Michael Conlon, Gerald Mills, Rowan Feely

Conference papers

This paper presents an investigation of wind observations made at three (of a network of ten) stations in Dublin. Two of the stations are located over different parts of the urbanized landscape and one is located at Dublin Airport, which exemplifies a typical meteorological station. The purpose of the analysis is to evaluate the nature of the wind resource in the urban area. The potential output of a range of commercially available micro wind turbines at one of the stations is considered. At this location, an anemometer is mounted in a similar manner to international examples of building mounted domestic …


Case Methods In Civil Engineering Teaching, Timothy A. Newson, Norbert J. Delatte Sep 2011

Case Methods In Civil Engineering Teaching, Timothy A. Newson, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

English: There have been significant changes in undergraduate civil engineering curricula in the last two decades. Key issues for university curriculum committees are selection and transference of appropriate skills and attributes for students to succeed in the industry. Despite significant changes occurring in teaching theories, civil engineering education still relies heavily on deductive instruction. Case-based teaching is one of the most widespread forms of inductive learning and this paper describes the differences between two of the most familiar types: 'case-histories' and 'case-studies'. These methods are presented using the Kansas City Hyatt Regency walkway collapse as an exemplar. The benefits of …


Smartpark Shock Absorbers For Wind Farms, Ganesh K. Venayagamoorthy, P. Mitra Sep 2011

Smartpark Shock Absorbers For Wind Farms, Ganesh K. Venayagamoorthy, P. Mitra

Electrical and Computer Engineering Faculty Research & Creative Works

Vehicle-to-grid power transactions will be integrated in future smart grids. This letter presents the novel idea of utilizing plug-in vehicle parking lots (SmartParks) to reduce the shock on the transmission lines connected to a wind farm caused by drastic variations in wind-power generation and to prevent the neighboring lines from overloading. the idea is demonstrated on a power system consisting of a large wind farm and six SmartParks modeled on a real-time simulator. © 2011 IEEE.


Frequency-Domain Turbo Equalization With Soft Successive Interference Cancellation For Single Carrier Mimo Underwater Acoustic Communications, Jian Zhang, Yahong Rosa Zheng Sep 2011

Frequency-Domain Turbo Equalization With Soft Successive Interference Cancellation For Single Carrier Mimo Underwater Acoustic Communications, Jian Zhang, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a low-complexity frequency-domain turbo equalizer (FDTE) combined with phase rotation compensation and soft successive interference cancellation (SSIC) for single carrier multiple-input multiple-output (MIMO) underwater acoustic (UWA) communications. Different from existing time-domain turbo equalizers in MIMO UWA systems, the proposed receiver implements low-complexity turbo equalization in the frequency domain to combat severe inter-symbol interference (ISI) and employs a layered structure to cope with unbalanced MIMO channels. Soft, rather than hard, successive interference cancellation (SIC) is employed in the layered iterative turbo detection to alleviate co-channel interference (CCI), and phase compensation is utilized within the layered FDTE to mitigate …


Robust Cns Regeneration After Complete Spinal Cord Transection Using Aligned Poly-L-Lactic Acid Microfibers, Andres Hurtado, Jared M. Cregg, Han B. Wang, Dane F. Wendell, Martin Oudega, Ryan J. Gilbert, John W. Mcdonald Sep 2011

Robust Cns Regeneration After Complete Spinal Cord Transection Using Aligned Poly-L-Lactic Acid Microfibers, Andres Hurtado, Jared M. Cregg, Han B. Wang, Dane F. Wendell, Martin Oudega, Ryan J. Gilbert, John W. Mcdonald

Chemical and Biochemical Engineering Faculty Research & Creative Works

Following spinal cord injury, axons fail to regenerate without exogenous intervention. In this study we report that aligned microfiber-based grafts foster robust regeneration of vascularized CNS tissue. Film, random, and aligned microfiber-based conduits were grafted into a 3 mm thoracic rat spinal cord gap created by complete transection. Over the course of 4 weeks, microtopography presented by aligned or random poly- l-lactic acid microfibers facilitated infiltration of host tissue, and the initial 3 mm gap was closed by endogenous cell populations. This bulk tissue response was composed of regenerating axons accompanied by morphologically aligned astrocytes. Aligned fibers promoted long distance …


Advances In Hydrogen Compression Ignition Internal Combustion Engines, Alberto Boretti Sep 2011

Advances In Hydrogen Compression Ignition Internal Combustion Engines, Alberto Boretti

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The turbocharged direct injection lean burn Diesel engine is the most efficient engine now in production for transport applications within heavy duty trucks applications full load brake engine thermal efficiencies up to 45% and reduced penalties in brake engine thermal efficiencies reducing the load by the quantity of fuel injected. the secrets of this engine's performances are the high compression ratio and the lean bulk combustion mostly diffusion controlled in addition to the partial recovery of the exhaust energy to boost the charging efficiency. the major downfalls of this engine are the carbon dioxide emissions and the depletion of natural …


Smartpark As A Virtual Statcom, Pinaki Mitra, Ganesh K. Venayagamoorthy, Keith Corzine Sep 2011

Smartpark As A Virtual Statcom, Pinaki Mitra, Ganesh K. Venayagamoorthy, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

Power electronic-Based FACTS devices such as STATCOMs are sometimes essential for voltage support in transmission networks. They can also be used for continuous operation of doubly fed induction generator-Based wind turbines during faults. However, these devices are quite expensive and therefore cannot be used extensively. This paper explores the potential of a low-cost solution that utilizes the reactive power and voltage support capabilities of plug-in vehicles parked in charging stations (SmartParks) so that they can behave as virtual STATCOMs. for this solution, a 12-bus multimachine power system is considered wherein one of the conventional units is replaced by a 400 …