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Acuta Enews August 2012 Vol. 41, No. 8 Aug 2012

Acuta Enews August 2012 Vol. 41, No. 8

ACUTA Newsletters

In this issue....

ACUTA Strategic Planning Retreat

What's on Your Desk?

Windstream Provides Calling Service to ACUTA

Are We stuck with "Islands" of UC Interoperability?

Operator Services

Novel & Adaptive Thinking: Working without FAQs

Member Benefit of the Month: Discounted Registration Fees

Info Link

Mentors Make a Difference

Consider Speaking Opportunities

LEED- Certified Building Stock Swells to 2 Billion Square Feet Worldwide

Welcome New Members

Check It Out


Fabrication And Characterization Of Biocomposites From Polylactic Acid And Bamboo Fibers, Sarah E. Royse Aug 2012

Fabrication And Characterization Of Biocomposites From Polylactic Acid And Bamboo Fibers, Sarah E. Royse

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Environmental concerns have been motivating research in the field of biodegradable materials, especially those from biological sources. Polylactic acid (PLA) is one biopolymer with the potential to replace some standard synthetic polymers. PLA is currently used for fibers, medical sutures, and some packaging, but is still used very little compared with synthetic polymers. One thing that can be done to expand the potential applications of PLA is to add fibers to create composite materials. Bamboo is a good choice for these fibers because it is abundant in many parts of the world, grows very quickly, and is widely unused. Composites …


A Model For Optimizing The Allocation Of Ethanol Production In The U.S., Anali Huggins Aug 2012

A Model For Optimizing The Allocation Of Ethanol Production In The U.S., Anali Huggins

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

In the last five years, fuel prices have fluctuated from 2.86$/gallon to 3.87$/gallon which represents an increase of 35%. This situation has collocated the ethanol manufacturing in an advantageous situation. However, a major problem that is faced by the ethanol producers is the high cost of transportation. The objective of this thesis study is to determine the optimal allocation of ethanol production in the U.S. in 2009 that minimizes the transportation cost. This thesis is based on the application of a linear programing model. The thesis is focused on two questions. The first is the optimal allocation of ethanol between …


Magnetic Properties Study Of The Mn-Al System With Additions Of B Or C And Mechanical Milling Techniques, Timothy E. Prost Aug 2012

Magnetic Properties Study Of The Mn-Al System With Additions Of B Or C And Mechanical Milling Techniques, Timothy E. Prost

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Recently a shift in the focus of permanent magnetic research has moved from Rare Earth (RE)-based alloys to those made from more readily available elements. Because of their relatively large magnetocrystalline anisotropy, L10 compounds have the potential for use as permanent magnet materials. One particular alloy that is readily available and inexpensive is near equi-atomic manganese and aluminum (Mn50-Al50). First characterized in 1958, it did not receive much attention until more recently when RE supply chain issues made the alloy more attractive for commercial and research applications. The ferromagnetic (FM) τ-phase (L10) is …


Fabrication And Characterization Of Thermomechanically Processed Sulfur And Boron Doped Amorphous Carbon Films, Lonnie Carlson Aug 2012

Fabrication And Characterization Of Thermomechanically Processed Sulfur And Boron Doped Amorphous Carbon Films, Lonnie Carlson

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Small scale, high power density, reliable, and long-life power supplies would be useful or even critical for space missions or the growing number of microdetectors, microsensors, and miniature vehicles. Alpha or beta particle voltaic devices could satisfy these requirements but have been shown to degrade quickly due to radiation damage. Amorphous carbon (a-C) PN junctions or PIN devices could provide radiation hardness and sufficiently high efficiency. As the range of alpha and beta particles in a-C is ~20-120μm, much thicker films than are typical are needed to maximize collection of the particle energy.

In this work, the fabrication of thermomechanically …


Healthcare Quality: Waiting Room Issues, Vineeth R. Yeddula Aug 2012

Healthcare Quality: Waiting Room Issues, Vineeth R. Yeddula

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

In today’s hyper-competitive market, customers are faced with many different options when deciding on a specific healthcare provider. Due to the varying options, quality and service stand out as two essential elements that influence the selection process. If the quality is not met, the healthcare organizations have to face several issues such as customer retention, value, safety, litigation, and reputation. Patient satisfaction has emerged as an increasingly important parameter in the assessment of health care quality. Waiting time is considered to be an important determinant of patient satisfaction. As patients experience a greater squeeze on their time, short waits seem …


Shear-Horizontal Vibration Modes Of An Oblate Elliptical Cylinder And Energy Trapping In Contoured Acoustic Wave Resonators, Huijing He, Jiashi Yang, John A. Kosinski Aug 2012

Shear-Horizontal Vibration Modes Of An Oblate Elliptical Cylinder And Energy Trapping In Contoured Acoustic Wave Resonators, Huijing He, Jiashi Yang, John A. Kosinski

Department of Mechanical and Materials Engineering: Faculty Publications

We study shear-horizontal free vibrations of an elastic cylinder with an oblate elliptical cross section and a traction-free surface. Exact vibration modes and frequencies are obtained. The results show the existence of thickness-shear and thickness-twist modes. The energy-trapping behavior of these modes is examined. Trapped modes are found wherein the vibration energy is largely confined to the central portion of the cross section and little vibration energy is found at the edges. It is also shown that face-shear modes are not allowed in such a cylinder. The results are useful for the understanding of the energy trapping phenomenon in contoured …


Classification Of Genomic Sequences By Latent Semantic Analysis, Samuel F. Way Aug 2012

Classification Of Genomic Sequences By Latent Semantic Analysis, Samuel F. Way

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Evolutionary distance measures provide a means of identifying and organizing related organisms by comparing their genomic sequences. As such, techniques that quantify the level of similarity between DNA sequences are essential in our efforts to decipher the genetic code in which they are written.

Traditional methods for estimating the evolutionary distance separating two genomic sequences often require that the sequences first be aligned before they are compared. Unfortunately, this preliminary step imposes great computational burden, making this class of techniques impractical for applications involving a large number of sequences. Instead, we desire new methods for differentiating genomic sequences that eliminate …


Simulation, Development And Deployment Of Mobile Wireless Sensor Networks For Migratory Bird Tracking, William P. Bennett Jr. Aug 2012

Simulation, Development And Deployment Of Mobile Wireless Sensor Networks For Migratory Bird Tracking, William P. Bennett Jr.

School of Computing: Dissertations, Theses, and Student Research

This thesis presents CraneTracker, a multi-modal sensing and communication system for monitoring migratory species at the continental level. By exploiting the robust and extensive cellular infrastructure across the continent, traditional mobile wireless sensor networks can be extended to enable reliable, low-cost monitoring of migratory species. The developed multi-tier architecture yields ecologists with unconventional behavior information not furnished by alternative tracking systems at such a large scale and for a low-cost. The simulation, development and implementation of the CraneTracker software system is presented. The system is shown effective through multiple proxy deployments on wildlife and has been operational for 10 months …


Automated Resonant Wireless Power Transfer To Remote Sensors From An Unmanned Aerial Vehicle, Brent Griffin Aug 2012

Automated Resonant Wireless Power Transfer To Remote Sensors From An Unmanned Aerial Vehicle, Brent Griffin

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Wireless magnetic resonant power transfer is an emerging technology that has many advantages over other wireless power transfer methods due to its safety, lack of interference, and efficiency at medium ranges. In this thesis, we develop a wire- less magnetic resonant power transfer system that enables unmanned aerial vehicles (UAVs) to provide power to, and recharge batteries of, wireless sensors and other electronics far removed from the electric grid. We address the difficulties of implementing and outfitting this system on a UAV with limited payload capabilities and develop a controller that maximizes the received power as the UAV moves into …


Cost-Effective Safety Treatments For Low-Volume Roads, Kevin D Schrum, Karla A. Lechtenberg, Cody S. Stolle, Ronald K. Faller, Dean L. Sicking Aug 2012

Cost-Effective Safety Treatments For Low-Volume Roads, Kevin D Schrum, Karla A. Lechtenberg, Cody S. Stolle, Ronald K. Faller, Dean L. Sicking

Nebraska Department of Transportation: Research Reports

No abstract provided.


Effects Of Acoustic Environments On Speech Comprehension By Native-English-Speaking Listeners, Zhao Peng, Lily M. Wang, Siu Kit Lau Aug 2012

Effects Of Acoustic Environments On Speech Comprehension By Native-English-Speaking Listeners, Zhao Peng, Lily M. Wang, Siu Kit Lau

Durham School of Architectural Engineering and Construction: Faculty Publications

This study investigates the effects of acoustic conditions on speech comprehension, rather than speech intelligibility as often reported in existing literature. Sets of 15-minute-long listening comprehension tests were developed based on the format of the Test of English for International Communication (TOEIC). Each test set includes four types of tasks: matching aural phrases to photographs, selecting appropriate responses to aural questions, and answering questions after listening to conversations (between two talkers) and talks (single talker). Within the Nebraska acoustics test chamber, native-English-speaking participants are asked to perform these tests under 15 acoustic conditions, from combinations of three background noise levels …


Two-Dimensional Blood Flow Velocity Estimation Using Ultrasound Speckle Pattern Dependence On Scan Direction And Velocity, Tiantian Xu Aug 2012

Two-Dimensional Blood Flow Velocity Estimation Using Ultrasound Speckle Pattern Dependence On Scan Direction And Velocity, Tiantian Xu

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Cardiovascular disease is the leading cause death in the United States. Although emergency surgery and medicine can be used for cardiovascular disease treatment, the survivors will suffer for it afterwards. Ultrasound blood flow measurement provides a noninvasive way for cardiovascular diseases diagnosis. In this dissertation, three algorithms for blood flow velocity measurements were investigated and optimized. Feature tracking has been previously proposed for vector velocity measurement. In Chapter 3, the optimal amplitude and time thresholds for feature extraction were investigated to minimize flow estimate variance while providing sufficient spatial and temporal coverage of flow area. A new method of lateral …


Analysis Of Fiber Bragg Gratings For Ultrasonic Detection, Tongqing Liu Aug 2012

Analysis Of Fiber Bragg Gratings For Ultrasonic Detection, Tongqing Liu

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Fiber optic sensors became an emerging technique to detect ultrasonic emissions in the last decade. Their light weight, immunity to electromagnetic interference and capacity of being multiplexed make them defeat their electronic counterparts in various applications. In this thesis we presented a novel fiber optic ultrasonic sensor based on pi phase shift fiber Bragg gratings. Numerical simulations were performed to study the characteristics of pi phase shift fiber Bragg gratings impinged by ultrasonic waves. The coupling theory was introduced to analyze the change of fiber Bragg gratings when impinged by ultrasonic waves, and the transfer matrix method was utilized to …


Routing Over The Interplanetary Internet, Joyeeta Mukherjee Aug 2012

Routing Over The Interplanetary Internet, Joyeeta Mukherjee

School of Computing: Dissertations, Theses, and Student Research

Future space exploration demands a Space Network that will be able to connect spacecrafts with one another and in turn with Earth's terrestrial Internet and hence efficiently transfer data back and forth. The feasibility of this technology would enable common people to directly access telemetric data from distant planets and satellites. The concept of an Interplanetary Internet (IPN) is only in its incubation stage and considerable amount of common standards and research is required before widespread deployment can occur to make IPN feasible.

We provide a comprehensive survey that presents a picture of the current space networking technologies and architectures. …


Statistical Software Properties: Definition, Inference And Monitoring, Javier A. Darsie Aug 2012

Statistical Software Properties: Definition, Inference And Monitoring, Javier A. Darsie

School of Computing: Dissertations, Theses, and Student Research

Software properties define how software systems should operate. Specifying correct properties, however, can be difficult and expensive as it requires deep knowledge of the system's expected behavior and the environment in which it operates. Automated analysis techniques to infer properties from code or code executions can mitigate that cost, but are still unable to go beyond state properties and the simplest patterns of temporal properties. This limitation renders properties that sacrifice fault detection power.

To address this problem, we introduce a new type of software properties called \textit{statistical properties}, which characterize significant statistical relationships among the values of variables across …


Purification Of Fibrinogen From Human Plasma, Ayman E. Ismail Aug 2012

Purification Of Fibrinogen From Human Plasma, Ayman E. Ismail

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

A solvent detergent treated fibrinogen was purified from human plasma by cryoprecipitation (cryo) followed by chemical precipitation using ethanol (EtOH) or ammonium sulfate (AS) as precipitating agents. Amounts of fibronectin (FN), factor XIII A-subunit (FXIIIA), factor XIII b-subunit (FXIIIB), and alpha2-antiplasmin (α2-AP) in the isolated fibrinogen were quantified. Thromboelastography (TEG) analysis was used to evaluate the clot strength of the isolated fibrinogen and to determine the ability of the ethanol and ammonium sulfate precipitations to eliminate the solvent detergent. Sodium dodecylsulfate-polyacrylamide gel analysis indicated that fibrinogen produced by each of these precipitation methods had similar purity. …


Simulation Of Tax Revenues From Individuals Receiving Advanced College Degrees, Dejing Kong Jul 2012

Simulation Of Tax Revenues From Individuals Receiving Advanced College Degrees, Dejing Kong

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

State governments always want graduates who received higher education in universities and colleges to stimulate the economic growth of the state. Many state universities want to contribute more to the state’s economy as well, and state universities frequently have relevant economic development activities and offices. The state universities normally receive annual budgeted financial support and occasional special funding from the state government while the state expects contributions to the economic growth and an educated citizen in return. In this research, the economic impact of a graduate degree funded by the state government was considered in the state of Nebraska.

Simulation …


Hydrologic Evaluation Of Established Rain Gardens In Lincoln, Nebraska, Andrew R. Anderson, Thomas G. Franti, David P. Shelton Jul 2012

Hydrologic Evaluation Of Established Rain Gardens In Lincoln, Nebraska, Andrew R. Anderson, Thomas G. Franti, David P. Shelton

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Increased urbanization has resulted in water quality and flooding problems for many receiving waters in the United States. Rain gardens are one type of best management practice commonly used in low impact development (LID). Many studies have evaluated large engineered bioretention cells in research settings. There is little information on the effectiveness of homeowner-maintained rain gardens that rely on deep percolation as the method for water exfiltration. Repeatable controlled experiments are very rare in hydrologic studies due to the inherent variability of weather data. The objective of this study was to evaluate the hydrologic properties of twelve established rain gardens …


Data Mining Of Protein Databases, Christopher Assi Jul 2012

Data Mining Of Protein Databases, Christopher Assi

School of Computing: Dissertations, Theses, and Student Research

Data mining of protein databases poses special challenges because many protein databases are non-relational whereas most data mining and machine learning algorithms assume the input data to be a relational database. Protein databases are non-relational mainly because they often contain set data types. We developed new data mining algorithms that can restructure non-relational protein databases so that they become relational and amenable for various data mining and machine learning tools. We applied the new restructuring algorithms to a pancreatic protein database. After the restructuring, we also applied two classification methods, such as decision tree and SVM classifiers and compared their …


A Hybrid Battery Model Capable Of Capturing Dynamic Circuit Characteristics And Nonlinear Capacity Effects, Taesic Kim Jul 2012

A Hybrid Battery Model Capable Of Capturing Dynamic Circuit Characteristics And Nonlinear Capacity Effects, Taesic Kim

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

A high-fidelity battery model capable of accurately predicting battery performance is required for proper design and operation of battery-powered systems. However, the existing battery models have at least one of the following drawbacks: 1) requiring intensive computation due to high complexity, 2) not applicable for electrical circuit design and simulation, and 3) not capable of accurately capturing the State of Charge (SOC) and predicting runtime of the battery due to neglecting the nonlinear capacity effects. This thesis proposes a novel hybrid battery model, which takes the advantages of an electrical circuit battery model to accurately predicting the dynamic circuit characteristics …


An Investigation Of Medical Device Design And Physical Ergonomics In Healthcare, Adam E. De Laveaga Jul 2012

An Investigation Of Medical Device Design And Physical Ergonomics In Healthcare, Adam E. De Laveaga

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

Human factors and process engineering are becoming a prominent area of research and application for industrial engineering principles as healthcare providers seek to improve patient safety, quality the optimization of resources. Human factors engineering and ergonomics play a crucial role in the pursuit of operational excellence and patient safety in healthcare. These disciplines contain the tools required to develop instrumentation, technology and training that can improve the usability of medical technology and the quality of care that patients receive. Designing tasks, tools and processes for optimal human use can enhance performance, reduce errors and improve safety. This thesis encompasses three …


Experimental Investigation Of Hard And Brittle Materials Machining Using Micro Rotary Ultrasonic Machining, Amey V. Patwardhan Jul 2012

Experimental Investigation Of Hard And Brittle Materials Machining Using Micro Rotary Ultrasonic Machining, Amey V. Patwardhan

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

The demand for miniaturized device and components is rapidly increasing in fields of aerospace, energy, optics, electronics and communication, automation and medical. Rotary Ultrasonic Machining (RUM) is capable of machining hard and brittle materials such as advanced ceramics, glass and silicon used in many industries. Rotary Ultrasonic Machining (RUM) is a hybrid machining process in which material is removed by conventional grinding and ultrasonic machining. Micro RUM is a downscaled version of a macro RUM and is similar to micro Ultrasonic Machining (micro USM), where the vibration takes place in work piece instead of tool.

The goal of this thesis …


Dynamics Of Depression Storage During Sprinkler Irrigation And Precipitation Events, Michael B. Mckinney Jul 2012

Dynamics Of Depression Storage During Sprinkler Irrigation And Precipitation Events, Michael B. Mckinney

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Surface depression storage (Ds) is the volume of precipitation excess which is stored by surface microrelief features of soils. The volume of water stored in surface depressions when precipitation rate exceeds infiltration rate reduces the amount of runoff generated. Because Ds is dependent on soil microrelief, land slope, and crop residue, tillage and management practices can have a considerable impact on the magnitude of this value.

When modeling irrigation systems and surface hydrology, depression storage is often treated as a static abstraction, meaning that maximum storage volume must be filled before runoff occurs. However, several researchers have documented …


Energy Efficiency Analysis And Optimization On Mobile Video Wireless Delivery, Jianxin Sun Jul 2012

Energy Efficiency Analysis And Optimization On Mobile Video Wireless Delivery, Jianxin Sun

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

Micro-electronic industry has been boosting the capability of wireless mobile devices on full-scale. However, battery, as the only power source of most mobile devices, is experiencing a relatively slow development. Therefore, how to optimally utilize the limited battery energy on mobile devices under a predefined performance requirement becomes a critical issue. On the other hand, it is still unclear that how the battery capacity consumption is allocated on different working pattern of a specific video codec under various tempo-spatial scales and parameters, which has posed a design challenge on power management on multimedia communication system. Furthermore, an optimization method is …


Quantity And Capacity Expansion Decisions For Ethanol In Nebraska And A Medium Sized Plant, Mahsa Khoshnoud Jul 2012

Quantity And Capacity Expansion Decisions For Ethanol In Nebraska And A Medium Sized Plant, Mahsa Khoshnoud

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

Corn-based ethanol is the leader of sustainable sources of energy in the United States due to the abundance of corn and the popularity of ethanol-gasoline mixes. Over the past decade, ethanol production has risen from 1.5 million gallons in 1999 to 13 million gallons in 2011. This increase in production requires expansion of ethanol plants. Since Nebraska is the second highest producer of ethanol, we focus our research on the expansion of ethanol plants in Nebraska.

The aim of this study is to develop an optimization model for capital investments in ethanol in Nebraska and a medium sized ethanol plant …


Design, Analysis And Testing Of Haptic Feedback System For Laparoscopic Graspers In In Vivo Surgical Robots, Nikhil Salvi Jul 2012

Design, Analysis And Testing Of Haptic Feedback System For Laparoscopic Graspers In In Vivo Surgical Robots, Nikhil Salvi

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Laparo-Endoscopic Single Site (LESS) Robotics Surgery is an advanced technology in the field of Minimally Invasive Surgery (MIS). The LESS surgical robots significantly improve the surgeon’s accuracy, dexterity and visualization, and reduce the invasiveness of surgical procedure results in faster recovery time and improved cosmetic results. In a standard robotic endosurgery, the palpation of tissues is performed by laparoscopic graspers located at the end effectors. The master-slave configuration in robotic surgery leads in remote access to the operation site. Therefore, surgeon’s ability to perceive valuable sensory information is severely diminished. Sensory information such as haptics, which is essential for safe …


Efficient Prestressed Concrete–Steel Composite Girder For Medium-Span Bridges, Yaohua Deng Jul 2012

Efficient Prestressed Concrete–Steel Composite Girder For Medium-Span Bridges, Yaohua Deng

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

In this dissertation, a new Prestressed Concrete-Steel Composite (PCSC) girder system is introduced. The PCSC girder is composed of a lightweight W-shape steel section with shear studs on its top and bottom flanges to achieve composite action with the pretensioned concrete bottom flange and the cast-in-place concrete deck. The PCSC girder is lightweight, economical, durable and easy to fabricate. To prove its feasibility and potential, this study is to investigate design and fabrication issues associated with the PCSC girder. A service design procedure is proposed using Age-adjusted Elasticity Modulus Method (AEMM) to evaluate the time-dependent stresses and strains in the …


On Heterogeneous User Demands In Peer-To-Peer Video Streaming Systems, Zhipeng Ouyang Jul 2012

On Heterogeneous User Demands In Peer-To-Peer Video Streaming Systems, Zhipeng Ouyang

School of Computing: Dissertations, Theses, and Student Research

A Peer-to-Peer (P2P) video streaming system usually consists of a large number of peers, which have heterogeneous physical properties. Orthogonal to the physical heterogeneity, there is another type of heterogeneity called demand heterogeneity. Namely, peers have their own demands on the quality and type of the streaming service. The problem of demand heterogeneity has received little attention and as a result current P2P video streaming systems cannot achieve satisfactory performance due to demand heterogeneity. In this dissertation, we study how to design efficient P2P video streaming systems with heterogeneous user demands.

First, we study the problem of heterogeneous user demands …


Economic Impact On Annual Profit Of A Retail Inventory Management System When Using Rfid And Considering Discrepancy Ratio, Inaccuracy Ratio, Backorders, And Federal Income Tax, Liyuan Zhang Jul 2012

Economic Impact On Annual Profit Of A Retail Inventory Management System When Using Rfid And Considering Discrepancy Ratio, Inaccuracy Ratio, Backorders, And Federal Income Tax, Liyuan Zhang

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

Radio Frequency Identification (RFID) emerged as an important technology with the ability to improve the efficiency and accuracy of object tracking. It has brought cost savings and added value to a wide variety of fields. Retail inventory management system is one of the beneficial fields. In order to better satisfy customers and to improve profit, retailers demand high accuracy in inventory management to service customers without redundant on-hand inventories. The RFID technology, which provides more accurate tracking, can improve retailers’ profit.

Two accuracy factors were proposed to determine the difference in the profit of a retailer inventory management system caused …