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Full-Text Articles in Engineering

News Media Environment, Selective Perception, And The Survival Of Preference Diversity Within Communication Networks, Frank C.S. Liu, Paul E. Johnson May 2011

News Media Environment, Selective Perception, And The Survival Of Preference Diversity Within Communication Networks, Frank C.S. Liu, Paul E. Johnson

JITP 2011: The Future of Computational Social Science

There is a natural tension between the effects on public opinion of social networks and the news media. It is widely believed that social networks tend to harmonize opinions within them, but the presence of media may accentuate diversity by inserting discordant messages. On the other hand, in a totalitarian state where the government controls the media, social networks may mitigate the homogenizing pressure of a regime’s propaganda. The tendency of opinion to follow the “official line” may be mitigated because opponents of the government interact on a personal level and bolster one another’s views. This paper employs agent-based modeling—an …


Topscholar®, Creating Opportunities [Brochure], Connie Foster, Jennifer Wilson Apr 2011

Topscholar®, Creating Opportunities [Brochure], Connie Foster, Jennifer Wilson

TopSCHOLAR® Presentations and Reports

No abstract provided.


Topscholar® Creating Opportunities [2011 Brochure], Connie Foster, Jennifer Wilson Mar 2011

Topscholar® Creating Opportunities [2011 Brochure], Connie Foster, Jennifer Wilson

TopSCHOLAR® Presentations and Reports

No abstract provided.


Rough Consensus And Running Code: Integrating Engineering Principles Into Internet Policy Debates, Christopher S. Yoo Mar 2011

Rough Consensus And Running Code: Integrating Engineering Principles Into Internet Policy Debates, Christopher S. Yoo

All Faculty Scholarship

This is the introduction to a symposium issue for a conference designed to bring the engineering community, policymakers, legal academics, and industry participants together in an attempt to provide policymakers with a better understanding of the Internet’s technical aspects and to explore emerging issues of particular importance to current broadband policy.


Infoextractor – A Tool For Social Media Data Mining, Chirag Shah, Charles File Jan 2011

Infoextractor – A Tool For Social Media Data Mining, Chirag Shah, Charles File

JITP 2011: The Future of Computational Social Science

We present InfoExtractor, a web-based tool for collecting data and metadata from focused social media content. InfoExtractor then provides this data in various structured and unstructured formats for easy manipulation and analysis. The tool allows social science researchers to easily collect data for quantitative analysis, and is designed to deliver data from popular and influential social media sites in a useful and easy to access way. InfoExtractor was designed to replace traditional means of content aggregation, such as page scraping and brute- force copying.


Researching Real-World Web Use With Roxy, A Research Proxy, Ericka Menchen-Trevino, Chris Karr Jan 2011

Researching Real-World Web Use With Roxy, A Research Proxy, Ericka Menchen-Trevino, Chris Karr

JITP 2011: The Future of Computational Social Science

Outside of a lab environment, it has been difficult for researchers to collect both behavioral and self-reported Web-use data from the same participants. To address this challenge we created Roxy, open source software that collects real-world Web-use data with participants’ informed consent. Roxy gathers Web log data as well as the text and HTML code of each page visited by participants. We describe Roxy’s data gathering capabilities and search functions and then illustrate how we used the software in a multi-method study. The use case examines selective exposure to political communication during the November 2010 U.S. general election campaign.


Tradeoffs In Accuracy And Efficiency In Supervised Learning Methods, Loren Collingwood, John Wilkerson Jan 2011

Tradeoffs In Accuracy And Efficiency In Supervised Learning Methods, Loren Collingwood, John Wilkerson

JITP 2011: The Future of Computational Social Science

Text is becoming a central source of data for social science research. With advances in digitization and open records practices, the central challenge has in large part shifted away from availability to usability. Automated text classification methodologies are becoming increasingly important within political science because they hold the promise of substantially reducing the costs of converting text to data for a variety of tasks. In this paper, we consider a number of questions of interest to prospective users of supervised learning methods, which are appropriate to classification tasks where known categories are applied. For the right task, supervised learning methods …


Facilitating Encounters With Political Difference: Engaging Voters With The Living Voters Guide, Deen G. Freelon, Travis Kriplean, John Morgan, W. Lance Bennett, Alan Borning Jan 2011

Facilitating Encounters With Political Difference: Engaging Voters With The Living Voters Guide, Deen G. Freelon, Travis Kriplean, John Morgan, W. Lance Bennett, Alan Borning

JITP 2011: The Future of Computational Social Science

Unlike 20th-century mass media, the Internet requires self-selection of content by its very nature. This has raised the normative concern that users may opt to encounter only political information and perspectives that accord with their preexisting views. This study examines the different ways that voters appropriated a new, purpose-built online engagement platform to engage with a wide variety of political opinions and arguments. In a deployment aimed at helping Washington state citizens make their 2010 election decisions, we find that users take significant advantage of three key opportunities to engage with political diversity: reading, acknowledging, and writing arguments on both …


Politics 2.0 With Facebook – Collecting And Analyzing Public Comments On Facebook For Studying Political Discourses, Chirag Shah, Tayebeh Yazdani Nia Jan 2011

Politics 2.0 With Facebook – Collecting And Analyzing Public Comments On Facebook For Studying Political Discourses, Chirag Shah, Tayebeh Yazdani Nia

JITP 2011: The Future of Computational Social Science

Analyzing publicly available content on various social media sites such as YouTube and Twitter, as well as social network sites such as Facebook, has become an increasingly popular method for studying socio-political issues. Such public-contributed content, primarily available as comments, let people express their opinions and sentiments on a given topic, news-story, or post, while allowing social and political scientists to extend their analysis of a political discourse to social sphere. We recognize the importance of Facebook in such analysis and present several approaches and observations of collecting and analyzing public comments from it. In particular, we demonstrate what it …


An Automated Snowball Census Of The Political Web, Abe Gong Jan 2011

An Automated Snowball Census Of The Political Web, Abe Gong

JITP 2011: The Future of Computational Social Science

This paper solves a persistent methodological problem for social scientists studying the political web: representative sampling. Virtu- ally all existing studies of the political web are based on incomplete samples, and therefore lack generalizability. In this paper, I combine methods from computer science and sampling theory to conduct an automated snowball census of the political web and constructs an all- but-complete index of English political websites. I check the robust- ness of this index, use it to generate descriptive statistics for the entire political web, and demonstrate that studies based on ad hoc sampling strategies are likely to be biased …


Obtaining Speech Assets For Judgement Analysis On Low-Pass Filtered Emotional Speech, John Snel, Charlie Cullen Jan 2011

Obtaining Speech Assets For Judgement Analysis On Low-Pass Filtered Emotional Speech, John Snel, Charlie Cullen

Conference papers

Investigating the emotional content in speech from acoustic characteristics requires separating the semantic con- tent from the acoustic channel. For natural emotional speech, a widely used method to separate the two channels is the use of cue masking. Our objective is to investigate the use of cue masking in non-acted emotional speech by analyzing the extent to which filtering impacts the perception of emotional content of the modified speech material. However, obtaining a corpus of emotional speech can be quite difficult whereby verifying the emotional content is an issue thoroughly discussed. Currently, speech research is showing a tendency toward constructing …


Effects Of Salinity And Sand Content On Liquid Limit And Hydraulic Conductivity, Behzad Fatahi, Mohammad Hadi Khabbaz, Sudip Basack Jan 2011

Effects Of Salinity And Sand Content On Liquid Limit And Hydraulic Conductivity, Behzad Fatahi, Mohammad Hadi Khabbaz, Sudip Basack

Faculty of Engineering and Information Sciences - Papers: Part A

Soil conditions of construction sites have become worse than ever due to the overpopulation in the metropolitan areas throughout the world. Likewise, the prevention of environmental risks due to individual activities is one of the most important subjects in the geo-environmental problems. Saline soils may induce several problems in geotechnical engineering projects such as infrastructure embankments, road construction and clay liners. Effect of the various concentrations of sodium chloride (NaCl) on several different soils including bentonite, kaolinite and fine sand mixtures has been evaluated. In addition, influence of salinity and the period of submergence on the hydraulic conductivity of soil …


Joint Analysis Of Beef Growth And Carcass Quality Traits Through Calculation Of Co-Variance Components And Correlations., H R. Mirzaei, Arunas P. Verbyla, W. S. Pitchford Jan 2011

Joint Analysis Of Beef Growth And Carcass Quality Traits Through Calculation Of Co-Variance Components And Correlations., H R. Mirzaei, Arunas P. Verbyla, W. S. Pitchford

Faculty of Engineering and Information Sciences - Papers: Part A

A joint growth-carcass model using random regression was used to estimate the (co)variance components of beef cattle body weights and carcass quality traits and correlations between them. During a four-year period (1994-1997) of the Australian "southern crossbreeding project", mature Hereford cows (N = 581) were mated to 97 sires of Jersey, Wagyu, Angus, Hereford, South Devon, Limousin, and Belgian Blue breeds, resulting in 1141 calves. Data included 13 (for steers) and 8 (for heifers) body weight measurements approximately every 50 days from birth until slaughter and four carcass quality traits: hot standard carcass weight, rump fat depth, rib eye muscle …


Novel Features Of Ars Selection In Budding Yeast Lachancea Kluyveri, Ivan Liachko, Emi Tanaka, Katherine A. Cox, Shau Chee C. Chung, Lu Yang, Arael Seher, Lindsay Hallas, Eugene Cha, Gina Kang, Heather Pace, Jasmine Barrow, Maki Inada, Bik Kwoon Tye, Uri Keich Jan 2011

Novel Features Of Ars Selection In Budding Yeast Lachancea Kluyveri, Ivan Liachko, Emi Tanaka, Katherine A. Cox, Shau Chee C. Chung, Lu Yang, Arael Seher, Lindsay Hallas, Eugene Cha, Gina Kang, Heather Pace, Jasmine Barrow, Maki Inada, Bik Kwoon Tye, Uri Keich

Faculty of Engineering and Information Sciences - Papers: Part A

Background: The characterization of DNA replication origins in yeast has shed much light on the mechanisms of initiation of DNA replication. However, very little is known about the evolution of origins or the evolution of mechanisms through which origins are recognized by the initiation machinery. This lack of understanding is largely due to the vast evolutionary distances between model organisms in which origins have been examined.Results: In this study we have isolated and characterized autonomously replicating sequences (ARSs) in Lachancea kluyveri - a pre-whole genome duplication (WGD) budding yeast. Through a combination of experimental work and rigorous computational analysis, we …


Prediction Model Of A Joint Analysis Of Beef Growth And Carcass Quality Traits, H R. Mirzaei, Arunas P. Verbyla, Wayne S. Pitchford Jan 2011

Prediction Model Of A Joint Analysis Of Beef Growth And Carcass Quality Traits, H R. Mirzaei, Arunas P. Verbyla, Wayne S. Pitchford

Faculty of Engineering and Information Sciences - Papers: Part A

A joint growth-carcass analysis was conducted to develop equations for predicting carcass quality traits associated with variation in growth path of crossbred cattle. During a four-year period (1994-1997) of the Australian "Southern Crossbreeding Project", mature Hereford cows (r = 581) were mated to 97 sires of Jersey, Wagyu, Angus, Hereford, South Devon, Limousin, and Belgian Blue breeds, resulting in 1141 calves. Data included body weight measurements of steers and heifers from birth until slaughter and four carcass quality traits: hot standard carcass weight, rump fat depth, rib eye muscle area, and intramuscular fat content. The model provides nine outputs: median …


Modeling Of Crossbred Cattle Growth, Comparison Between Cubic And Piecewise Random Regression Models, H R. Mirzaei, Wayne S. Pitchford, Arunas P. Verbyla Jan 2011

Modeling Of Crossbred Cattle Growth, Comparison Between Cubic And Piecewise Random Regression Models, H R. Mirzaei, Wayne S. Pitchford, Arunas P. Verbyla

Faculty of Engineering and Information Sciences - Papers: Part A

Two analyses, cubic and piecewise random regression, were conducted to model growth of crossbred cattle from birth to about two years of age, investigating the ability of a piecewise procedure to fit growth traits without the complications of the cubic model. During a four-year period (1994-1997) of the Australian "Southern Crossbreeding Project", mature Hereford cows (N = 581) were mated to 97 sires of Angus, Belgian Blue, Hereford, Jersey, Limousin, South Devon, and Wagyu breeds, resulting in 1141 steers and heifers born over four years. Data included 13 (for steers) and eight (for heifers) live body weight measurements, made approximately …


Multiplicity Of Solutions For Quasilinear Elliptic Equations With Critical Exponential Growth, Yanqin Fang, Jihui Zhang Jan 2011

Multiplicity Of Solutions For Quasilinear Elliptic Equations With Critical Exponential Growth, Yanqin Fang, Jihui Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper we consider a system of N-Laplacian elliptic equa- tions with critical exponential growth. The existence and multiplicity re- sults of solutions are obtained by a limit index method and Trudinger- Moser inequality.


Sensitization Behaviour Of 11-12% Cr Aisi 409 Stainless Steel During Low Heat Input Welding, Cornelis Janise Van Niekerk, Madeleine Du Toit Jan 2011

Sensitization Behaviour Of 11-12% Cr Aisi 409 Stainless Steel During Low Heat Input Welding, Cornelis Janise Van Niekerk, Madeleine Du Toit

Faculty of Engineering and Information Sciences - Papers: Part A

The study comprised of the investigation into the sensitization characteristics of AISI 409 titanium stabilized ferritic stainless steel during low heat input welding. AISI 409 is a fully ferritic stainless steel used in catalytic converters and tubing for automotive exhaust systems due to the supposition that sensitization does not occur during low heat input welding. Two plates of 2 and 4 mm were tested for sensitization during low heat input welding. The study confirmed that chromium carbide (M23C6) precipitation occurs on the grain boundaries in the heat-affected zone with consequent depletion of Cr adjacent to the …


Effects Of A Brief Cognitive Intervention Aimed At Communicating The Negative Reinforcement Explanation For Smoking On Relevant Cognitions And Urges To Smoke, Mairtin S. Mcdermott, Theresa M. Marteau, Peter Hajek Jan 2011

Effects Of A Brief Cognitive Intervention Aimed At Communicating The Negative Reinforcement Explanation For Smoking On Relevant Cognitions And Urges To Smoke, Mairtin S. Mcdermott, Theresa M. Marteau, Peter Hajek

Faculty of Engineering and Information Sciences - Papers: Part A

Introduction:The aim of the current study was to assess the impact of an intervention aimed at communicating the negative reinforcement explanation for smoking, a set of ideas derived from popular self-help books, upon participants' cognitions and urges to smoke. Methods: Smokers (n = 205) undergoing standard stop-smoking treatment were randomised to receive either the experimental intervention, a brief intervention aimed at communicating the explanation or a control intervention, a video on the health risks of smoking. Outcomes were participants' acceptance of the negative reinforcement explanation for smoking, positive outcome expectations for smoking, self-efficacy and urges to smoke reported at one …


Can Australia High Speed Rail Overcome It's Bumpy History?, Philip Laird Jan 2011

Can Australia High Speed Rail Overcome It's Bumpy History?, Philip Laird

Faculty of Engineering and Information Sciences - Papers: Part A

The Australian Government has released an "implementation" study for high speed rail (or HSR) on the east coast with a further study to follow. The proposal looks at corridors between Melbourne, Sydney and Brisbane. It includes the option of three-hour travel times between Sydney and Melbourne, with tickets costing around $100. With the projected price of the project starting at around $60 billion, and Australia's chequered history with HSR, it is not unreasonable to ask whether the project will commence. In this case, would Sydney to Newcastle take preference over Sydney to Melbourne?


Three-Dimensional Nonlinear Analysis Of Seismic Ground Response Of Soft Soils In Shanghai, Qingsheng Chen, Guangyun Gao, Junfeng He Jan 2011

Three-Dimensional Nonlinear Analysis Of Seismic Ground Response Of Soft Soils In Shanghai, Qingsheng Chen, Guangyun Gao, Junfeng He

Faculty of Engineering and Information Sciences - Papers: Part A

Reduced order bounding surface model was employed to study 3-D seismic ground response of site considering the nonlinearity of soft soils in Shanghai. A nonlinear procedure for response analysis of horizontal layered sites subjected to multidirectional earthquake loading was used to study vertical and horizontal ground responses, respectively, under unidirectional and multidirectional base excitations (Taft). Also, the development of ratio of vertical and horizontal peak acceleration and the effects of the variation of groundwater table on the characteristics of seismic responses were studied. The study results show that the characteristics of vertical seismic ground response are much different from those …


Cavity Enhanced Stimulated Brillouin Scattering In An Optical Ship For Multiorder Stokes Generation, Ravi Pant, Enbang Li, Duk-Yong Choi, Christopher Poulton, Stephen J. Madden, Barry Luther-Davies, Benjamin J. Eggleton Jan 2011

Cavity Enhanced Stimulated Brillouin Scattering In An Optical Ship For Multiorder Stokes Generation, Ravi Pant, Enbang Li, Duk-Yong Choi, Christopher Poulton, Stephen J. Madden, Barry Luther-Davies, Benjamin J. Eggleton

Faculty of Engineering and Information Sciences - Papers: Part A

We report the first demonstration of on-chip cascaded stimulated Brillouin scattering (SBS). Cascaded SBS is characterized in a 4 cm long chalcogenide ( As2S3 ) rib waveguide where the end facet reflections provide a monolithic Fabry–Perot (FP) resonator. The presence of the FP cavity reduces the Brillouin gain threshold, which enables observation of cascaded SBS at reduced pump powers. We observe up to three orders of Stokes waves in the backscattered signal at a coupled peak power of 1.34 W . Anti-Stokes waves due to four-wave mixing between the pump and the Stokes wave were observed in the forward spectrum.


Terahertz-Wave Parametic Oscillator With Misalignment-Resistant Tuning Cavity, Bo Sun, Sanxing Li, Jinsong Liu, Enbang Li, Jianquan Yao Jan 2011

Terahertz-Wave Parametic Oscillator With Misalignment-Resistant Tuning Cavity, Bo Sun, Sanxing Li, Jinsong Liu, Enbang Li, Jianquan Yao

Faculty of Engineering and Information Sciences - Papers: Part A

We demonstrate a terahertz-wave parametric oscillator (TPO) with a corner-cube resonator consisting of a corner-cube prism (CCP) and a flat mirror. By using the cavity configuration proposed in this Letter, the generation of tunable monochromatic terahertz (THz) waves can be achieved just by rotating the flat mirror instead of rotating the TPO cavity relative to the pump beam. The THz-wave output intensity and pulse width can be controlled periodically by rotating the CCP around the cavity axis. The TPO stability against cavity misalignment is significantly improved by at least 1 to 2 orders of magnitude compared with the conventional plane–parallel …


Enhanced Gas Drainage From Undersaturated Coal Bed Methane Reservoirs, Dennis John Black, Naj Aziz, Ting Ren Jan 2011

Enhanced Gas Drainage From Undersaturated Coal Bed Methane Reservoirs, Dennis John Black, Naj Aziz, Ting Ren

Faculty of Engineering and Information Sciences - Papers: Part A

Traditional methods of coal seam gas drainage rely on the use of reservoir pressure reduction to promote gas desorption from the coal matrix. Studies in coal mining gas drainage operations, particularly in coal seams that are deeply undersaturated and have low permeability, found the rate of reservoir pressure reduction was prohibitively slow. In such conditions, lengthy production delays have been experienced while additional gas drainage drilling is undertaken in an attempt to reduce seam gas content below specified threshold limits. Such drilling represents a high additional operating cost and yields low total gas production whilst adversely impacting the mine's gas …


An Analytical Method For Predicting Cogging Forces In Linear Induction Motors, Mochammad Rusli, Jeffrey W. Moscrop, Donald Platt, Christopher David Cook Jan 2011

An Analytical Method For Predicting Cogging Forces In Linear Induction Motors, Mochammad Rusli, Jeffrey W. Moscrop, Donald Platt, Christopher David Cook

Faculty of Engineering and Information Sciences - Papers: Part A

Cogging in a linear machine can be described as a variation in the magnetic forces as the machine travels along its linear uis. This effect can have a severe impact on the overall precision and even stability of the linear uis. In this paper an analytical method to predict the cogging forces in Linear Induction Moton (LIMs) is presented. An aecurate estimation of cogging is useful during the LIM design stage to help millimize this performance limiting factor. One common method used to predict cogging torques in rotary induction moton is the tooth overlap method. Due to the complexity of …


Robust And Intelligent Control Methods To Improve The Performance Of A Unified Power Flow Controller, C Benachaiba, Ahmed M. Haidar, M L. Doumbia Jan 2011

Robust And Intelligent Control Methods To Improve The Performance Of A Unified Power Flow Controller, C Benachaiba, Ahmed M. Haidar, M L. Doumbia

Faculty of Engineering and Information Sciences - Papers: Part A

The important factor disturbing the modern power systems today is load flow control. The Unified Power Flow Controller (UPFC) is an effective way for controlling the power flow and can provide damping capability during transient conditions. The UPFC is controlled conventionally using PI controller. This paper presents two robust controllers to improve the performance of the UPFC. The first is a RST controller based on the principle of pole placement and the second is an intelligent controller based on the principle of fuzzy logic optimized by Genetic Algorithm (GA).


Offline Programming For Short Batch Robotic Welding, Nathan Larkin, Aleksandar Milojevic, Zengxi Pan, Joseph Polden, John Norrish Jan 2011

Offline Programming For Short Batch Robotic Welding, Nathan Larkin, Aleksandar Milojevic, Zengxi Pan, Joseph Polden, John Norrish

Faculty of Engineering and Information Sciences - Papers: Part A

Robotics based automation has many advantages over both manual operation and dedicated hard automation. In practice however the robot programming overhead and high cost of dedicated jigging are serious impediments to its use for short production runs. Offline programming packages offer an attractive alternative to reduce programming time and robot down time, however many of the available packages are fairly complex and treat the geometric programming and welding operation separately. The paper will describe the development of alternative approaches and the evaluation of an integrated offline robotic welding package (RinasWeld) which addresses these issues and makes low volume robotic welding …


Spectral Triples: Examples And Index Theory, Alan L. Carey, John Phillips, Adam C. Rennie Jan 2011

Spectral Triples: Examples And Index Theory, Alan L. Carey, John Phillips, Adam C. Rennie

Faculty of Engineering and Information Sciences - Papers: Part A

The main objective of these notes is to give some intuition about spectral triples and the role they play in index theory. The notes are basically a road map, with much detail omitted. To give a complete account of all the topics covered would require at least a book, so we have opted for a sketch.


An Opportunistic Scheduler For Dense Wlans, Kwan-Wu Chin Jan 2011

An Opportunistic Scheduler For Dense Wlans, Kwan-Wu Chin

Faculty of Engineering and Information Sciences - Papers: Part A

The demand for bandwidth by multimedia applications remains unabated. This is particular critical given the growing number of devices with WiFi capability, and the ubiquity of Wireless Local Area Networks (WLANs). These trends have spurred researchers to develop low-cost and backward compatible solutions to increase the capacity of WLANs. One approach is to deploy additional Access Points (APs), and strategies to manage channel, user, and transmit power. As a result, stations are likely to be near one or more APs, and therefore are more likely to experience high data rates. In this paper, we take advantage of this fact to …


Location Based Services With Personal Area Network For Community And Tourism Applications, Montserrat Ros, Matthew D'Souza, Adam Postula, I Maccoll Jan 2011

Location Based Services With Personal Area Network For Community And Tourism Applications, Montserrat Ros, Matthew D'Souza, Adam Postula, I Maccoll

Faculty of Engineering and Information Sciences - Papers: Part A

The Infopoint Explorer is an outdoor wireless personal area network for location-based services that allows users to access locality information interactively using mobile computing devices such as PDAs and smartphones. The Infopoint explorer was used to study the limitations imposed by inexpensive and popular wireless technologies such as Bluetooth for outdoor location-based services. The Infopoint Explorer functioned as a multimedia guidebook that allowed access to location-specific information using wireless Infopoints. The Infopoints detect and attempt to transfer multimedia content to nearby mobile computing devices using Bluetooth connectivity. An adaptive Bluetooth Inquiry Access Code algorithm was developed to reduce the time …